ERCO guide.pdf

8/22/2019 ERCO guide.pdf

http://slidepdf.com/reader/full/erco-guidepdf 1/434

1Edition: 01/03/2010 | Updated version at www.erco.com

Basics

Simulation and calculation

Indoor lighting

Lighting control

Designing with light

Outdoor lighting

Lighting technology

Glossary

The Guide provides extensiveinformation on topics rangingfrom the physical basics of light-ing through to possible solutionsfor specific lighting situations

– in short, a veritable encyclo-paedia of architectural lighting.The knowledge modules makeuse of the interactive possibilitiesoffered by the Internet, e.g. forillustrating time-dependent phe-nomena, experiments or contrastsbetween alternative solutions:www.erco.com/guide

E Guide




E GuideBasics

It is inadequate simply to portraythe eye as an optical system whendescribing human perception. Italso needs to be explained howthe image is interpreted. Both theperceptual psychology and theobjects of perception are impor-tant factors in understandinglighting design.

History Seeing and percep-tion




E GuideBasics

History

Right up until the 18th centurypeople only had two light sourcesat their disposal: natural daylightand the flame – the latter beingthe only artificial light sourcesince the Stone Age. These twotypes of lighting dictated thepatterns of life and architecturedown through the ages, but anew epoch was ushered in withthe invention of gas lighting and

then electric lighting.

Quantitative lightingdesign

Qualitative lightingdesign

Perception-orientatedlighting design




With the advent of electricallighting, obtaining illuminancelevels similar to those of daylightbecame a question of how muchtechnical effort one was prepared

to invest. At the end of the 19th century, one attempt at provid-ing street lighting was to mountfloodlights on lighting towers.However, the glare and harshshadow produced caused moredisadvantages than advantagesand so this form of outdoor light-ing was soon abandoned.Whereas inadequate light sourceswere the main problem initially,a prime concern later on washow to sensibly deal with theoverabundance of light. Increas-ing industrialisation gave rise tointensive studies in the field of workplace lighting, investigat-

ing the influence of illuminancelevels and lighting type onproduction efficiency. The stud-ies resulted in extensive rulesand regulations governing theminimum illuminance levels, thequalities of colour rendition andglare limitation. This catalogueof standards was to serve as aguideline for lighting far beyondthe area of the workplace; in fact,it still determines the practiceof lighting design right up tothe present day. However, thisapproach left the psychology of perception totally unconsidered.The issues of how people perceivestructures clearly and how light-ing also conveys an aestheticeffect were beyond the scope of the quantitative lighting rulesand regulations.

The American Electric Light Tower(San José 1885)

E GuideBasics | History

Quantitative lighting design




Restricting the view of humanperception to a physiologicallyorientated level led to unsat-isfactory lighting concepts.Approaches at a new lightingphilosophy that no longer solelyconsidered quantitative aspectsarose in the USA after World WarII. Expanding the physiology of the visual apparatus by addingthe psychology of perception

meant that all factors involvedin the interaction between theperceiving observer, the objectviewed and the facilitatingmedium of light now came underconsideration. The perception-orientated lighting design nolonger primarily thought in thequantitative terms of illuminancelevels or luminance distribution,but in terms of the qualitativefactors.


Qualitative lighting design





Perception-orientated lighting design

The perception-orientatedlighting design of the 1960s nolonger considered man and hisneeds as a mere recipient of hisvisual surroundings but as anactive factor in the perceptionprocess. The designers analysedwhat was the significance of theindividual areas and functions.Using the pattern of meaningthus established, it was then

possible to plan the lighting asa third factor and to develop anappropriate lighting design. Thisrequired qualitative criteria and acorresponding vocabulary, whichin turn allowed both the require-ments placed on a lighting systemand the functions of the light tobe described.

Richard Kelly William Lam




Richard Kelly (1919-1977) wasa pioneer of qualitative lightingdesign who borrowed existingideas from perception psychol-ogy and theatrical lighting and

combined them into a uniformconcept. Kelly broke away fromthe rigid constraints of using uni-form illuminance as the centralcriterium of the lighting design.He replaced the question of light-ing quantity with the question of individual qualities of light. Thesewere designed according to aseries of lighting functions, whichwere in turn geared towards theperceiving observer. In the 1950sKelly made a distinction herebetween three basic functions:ambient luminescence, focal glowand play of brilliants.

E GuideBasics | History | Perception-orientated lighting design

Richard Kelly

Introduction





Richard Kelly

Focal glow

To arrive at a differentiation,Kelly came up with a secondform of light, which he referredto as ”focal glow“. This is wherelight is first given the expresstask of actively helping to con-vey information. The fact thatbrightly lit areas automaticallydraw our attention now comesinto consideration. By using asuitable brightness distributionit is possible to order the wealthof information contained in anenvironment. Areas containingessential information can beemphasised by accented lighting,whereas secondary or distracting

information can be toned down

Play of brilliantsThe third form of light, ”playof brilliants“, results from theinsight that light not only drawsour attention to information, butcan also represent information inand of itself. This applies aboveall to the specular effects thatpoint light sources can produceon reflective or refractive materi-als. Furthermore, the light sourceitself can also be considered to bebrilliant. This ”play of brilliants“can add life and ambiance, espe-cially to prestigious venues. Whatwas traditionally produced bychandeliers and candlelight cannow be achieved in a modernlighting design by the targeteduse of light sculptures or by cre-ating brilliant effects on illumi-nated materials.

Ambient luminescenceKelly called the first and foun-dational form of light ”ambientluminescence“. This is the elementof light that provides general

illumination of the surroundings;it ensures that the surroundingspace, its objects and the peoplethere are visible. This form of lighting facilitates general orien-tation and activity. Its universaland uniform orientation meansthat it largely follows along thesame lines as quantitative light-ing design, except that ambientluminescence is not the finalobjective but just the founda-tion for a more comprehensivelighting design. The aim is not to

produce blanket illumination, or”one size fits all“ lighting at thesupposed optimum illuminancelevel, but to have differentiatedlighting that builds on the base

layer of the ambient light.

by applying a lower lighting level.

This facilitates a fast and accurateflow of information, wherebythe visual environment is easilyrecognised in terms of its struc-tures and the significance of theobjects it contains. This applies just as equally to or ientationwithin the space (e.g. the abilityto distinguish quickly between amain entrance and a side door) asfor emphasising certain objects,such as when presenting goodsfor sale or when highlighting themost valuable sculpture in a col-lection.





Richard Kelly

Glass House

Architect: Philip JohnsonLocation: New Canaan,Connecticut, 1948-1949

It was on this Glass House projectthat Kelly developed the basicprinciples of indoor and outdoorlighting which he was to laterapply to countless residential andbusiness properties. Kelly avoidedthe use of blinds for the sunlightbecause he found they obscuredthe view and impaired the feel-ing of distant space. Instead, toreduce the harsh daytime bright-ness contrast between insideand outside, Kelly used dimmedlighting on the interior walls. Forthe night, he designed a conceptthat works with the reflection

of the glass facade and retainsthe spatial feeling. Kelly recom-mended candles for the interioras this would give sparkle and addan exciting atmosphere. Severallighting components in the out-door area augment the view outof the living area and create spa-tial depth. Projectors on the roof illuminate the front lawn and thetrees beside the house. Additionalprojectors highlight the trees

in the middle ground and thebackground, thereby making thelandscape backdrop visible.

Photos courtesy of the Kelly

Collection.

Seagram Building

Architects: Ludwig Mies van derRohe and Philip Johnson

Location: New York, New York,1957

The vision behind the SeagramBuilding was to have a tower of light that would be recognisablefrom afar. Working together withMies van der Rohe and PhilipJohnson, Kelly achieved this aimby having the building shine fromthe inside out. This was doneusing luminous ceilings in theoffice levels, whereby a two-stagelight switch for the fluorescentlamps enabled energy to be savedat night. The illumined area at theplinth of the building gave theimpression that this multi-storeybuilding is floating above thestreet. An impressive view intothe building at night is affordedthanks to uniform vertical illu-mination of the building’s core,produced by recessed ceilingluminaires. A carpet of light startsin the indoor area and continuesonto the forecourt. To achieve auniform pattern of solar protec-tion on the facade during thedaytime, the blinds on the win-dows only have three settings:open, closed and half-open.





Richard Kelly

New York State Theater

Lincoln Center for the PerformingArtsArchitect: Philip Johnson

Location: New York, New York,1965

For the New York State TheaterKelly explored the use of crystal-line structures for the design of the chandelier in the auditoriumand the lighting of the balconybalustrades in the foyer. Thechandelier in the auditorium hada diameter of about three metersand consisted of a number of smaller ”diamonds of light“. Inthe foyer, the luminaires on thebalustrade were designed to looklike jewels in a crown, therebyunderlining the grandeur of the

room. The light sources wereshielded towards the front side of the balustrades, but on the insidetheir multi-facetted structureproduced impressive reflections.This results in brilliance effectscomparable with the sparkle of precious stones. In addition, Kellyalso conceived the lighting in allthe other areas of the LincolnCenter, except the interior of theMetropolitan Opera House.

Kimbell Art Museum

Architect: Louis I. KahnLocation: Fort Worth, Texas, 1972

The clever use of natural lightin the Kimbell Art Museumoriginates from the teamworkof Louis Kahn and Richard Kelly.Kahn designed a series of North-South orientated galleries whosevaulted ceilings featured a sky-light running along their apexes,while Kelly was responsible forthe daylight reflector systemmade of curved aluminium plate.Perforations allow daylight topenetrate through this plate,thereby reducing the contrastbetween the underside of thisreflector and the daylight-illu-minated concrete vaulting. Thecentral section of this dishedaluminium is kept free of per-forations so that direct daylightis shut out. In areas with no UV protection requirements, such asthe entrance or the restaurant, acompletely perforated reflectoris used. Computer programs wereused to calculate the reflectorcontour and the lighting proper-ties that were to be expected.The underside of the daylightreflector system was fitted withtracks and spotlights. Kelly sug-gested putting plants in the inner

courtyards in order to tone downthe harsh daylight for the indoorareas.





Richard Kelly

Yale Center For British Art

Architect: Louis I. KahnLocation: New Haven,Connecticut, 1969-1974

Louis Kahn teamed up with Kellyto design a system of skylightsfor the illumination in the YaleCenter for British Art. The designbrief from the museum was thaton sunny and overcast days thepictures were to be exclusivelyilluminated by daylight. Artificiallighting was only to be mixed inwhen there was very low daylight.The domed skylights feature apermanently mounted louvreconstruction on the topside,allowing diffuse northern lightinto the building while avoidingdirectly incident light on walls or

floors when the sun is high. Theskylights are made of an upperPlexiglas dome with UV-protec-tion and a sandwich construc-tion consisting of: a translucentplastic plate for dust protection,a mirror-finish light diffuser anda bi-laminar, acrylic, prismaticlens underneath. Tracks on theundersides of the domed skylightshold wallwashers and spotlights.The design process utilised com-puter calculations and full-scalemodels.





William Lam

In the 1970s, William M. C. Lam(1924-), one of the most com-mitted advocates of qualitativelyorientated lighting design, pro-duced a list of criteria, or rather

a systematic, context-orientatedvocabulary for describing therequirements placed on a light-ing system. Lam distinguishedbetween two main groups of cri-teria: the ”activity needs“, whichare the needs resulting from per-forming activities within a visualenvironment, and the ”biologicalneeds“, which sum up the psy-chological demands placed ona visual environment and areapplicable in every context.

Introduction




Activity needsThe ”activity needs“ describe theneeds resulting from perform-ing activities within a visualenvironment. The characteristics

of the visual task at hand are thecrucial factor for these needs. Theanalysis of the activity needs istherefore largely identical withthe criteria for quantitative light-ing. There is also considerableagreement for this area when itcomes to the objectives of light-ing design. The aim is to arriveat a functional lighting that willprovide the optimum visual con-ditions for the activity in question– be it work, leisure activities orsimply moving through the space.In contrast to the proponents

of quantitative lighting design,Lam objects to a uniform lightingthat is simply designed to suitwhatever is the most difficultvisual task. Instead, he proposes a

differentiated analysis of all thevisual tasks that arise, an analysisconducted according to location,type and frequency.

Biological needs

Lam sees the second complexof his system, i.e. the ”biologicalneeds“, as being more essential.The biological needs sum upthe psychological demands thatare placed on a visual environ-ment and are applicable in everycontext. Whereas activity needsresult from a conscious involve-ment with the surroundings andare aimed at the functionality of a visual environment, biologicalneeds largely concern uncon-scious requirements which arefundamental for evaluating asituation emotionally. They areconcerned with the feeling of wellbeing in a visual environ-ment. The starting point for Lam’sdefinition is the fact that ourattention is only dedicated to onespecific visual task in momentsof utmost concentration. Ourvisual attention almost alwayswidens to observe our entire sur-roundings. This allows changes

in the environment to be perceived

immediately and behaviour to beadapted to the altered situationwithout delay. The emotionalevaluation of a visual environmentdepends not least on whether thatenvironment clearly presents therequired information or whether itconceals it from the observer.


William Lam

OrientationOf all the fundamental psycho-logical demands placed on avisual environment, Lam ranks theneed for clear orientation as par-amount. Orientation can be ini-tially understood in spatial termshere. In which case, it would thenrelate to how discernable desti-nations and routes are and tothe spatial location of entrances,exits and other specific facilitieswithin the environment, e.g. areception desk or the individualareas of a department store. Butorientation also concerns infor-mation on further aspects of thesurroundings, such as the time of day, the weather or what is goingon in that area. If this informa-tion is missing, as may be the casein closed spaces in departmentstores or in the corridors of large

buildings, then the environment isperceived as unnatural and evenoppressive. It is only by leavingthe building that we can catch upwith the information deficit.

Orientation Time of day

Weather Surroundings





William Lam

DiscernabilityA second group of psychologi-cal needs concerns how well thesurrounding structures can bediscerned and comprehended.

The first point to note here isthat all areas of the spaces aresufficiently visible. This is thedecisive factor for our feeling of security within a visual environ-ment. Dark corners in subways orin the corridors of large buildingsmay harbour danger, in the sameway as glaringly overlit areas.Comprehension of our surround-ings does not simply mean thatabsolutely everything has to bevisible however, it also includesan element of structuring, i.e. theneed for a clearly structured andordered environment. We perceivesituations as positive not only

when the form and structure of the surrounding architecture areclearly discernable, but also whenthe essential areas are clearlydelineated from their background.

Instead of constituting a confus-ing and possibly contradictorydeluge of information, a spacepresented in this way will featurea comprehensible number of

properties that build into a clearlystructured whole. Having a niceview or other points of visualinterest, such as a work of art,are also important for relaxation.

Security Structuring

View

CommunicationA third area covers the balancebetween man’s need for com-munication and his requirementfor a defined private sphere. Bothextremes here are perceived asnegative, i.e. complete isolationas well as ”life in a goldfish bowl“.A given space should facilitatecontact with other people, yetat the same time it should also

allow private areas to be defined.One such private area could bedefined by a patch of light thatpicks out a group of seats or aconference table from the over-all surroundings within a largerroom.

Public life Communication

Contemplation




The majority of the informationthat we receive about the worldaround us comes through oureyes. Light is not only an essentialprerequisite, it is the medium bywhich we are able to see. Throughits intensity, the way it is distrib-uted and through its properties,light creates specific conditionswhich can influence our percep-tion. Lighting design is, in fact,

the planning of our visual envi-ronment. Good lighting designaims to create perceptual con-ditions which allow us to workeffectively and orient ourselvessafely while promoting a feelingof well-being in a particularenvironment. At the same timeit enhances the environment inan aesthetic sense. The physicalqualities of a lighting situationcan be calculated and measured.Ultimately, it is the actual effectthe lighting has on the user of aspace and his subjective percep-tion, that decides whether alighting concept is successful ornot.

E GuideBasics

Seeing and perception

Physiology of the eye Psychology of seeing Constancy

Perception of gestalt Objects of perception



16

L

3UNLIGHT

/VERCASTSKY

4ASKLIGHTING

#IRCULATIONZONELIGHTING

3TREETLIGHTING

-OONLIGHT

Edition: 20/09/2007 | Updated version at www.erco.com

When describing human percep-tion, it is inadequate to portraythe eye as an optical system. Theprocess of perception is not amatter of how an image of ourenvironment is transferred to theretina, but how the image isinterpreted and how we dif-ferentiate between objects withconstant properties in a changingenvironment.

E GuideBasics | Seeing and perception

Physiology of the eye

Optical system Receptors Adaptation




Eye and camera The process of perception isfrequently explained by compar-ing the eye with a camera. In thecase of the camera, an adjust-able system of lenses projects

the reversed image of an objectonto a film. The amount of lightis controlled by a diaphragm.After developing the film andreversing the image during theenlarging process, a visible, two-dimensional image of the objectbecomes apparent. Similarly, inthe eye, a reversed image is projected onto the retina of the eyevia a deformable lens. The iristakes on the function of the dia-phragm, the light-sensitive retinathe role of the film. The imageis then transported via the opticnerve from the retina to the brain,where it is adapted in the visual

cortex and made available to theconscious mind.In regard to the eye, however,there are considerable differ-ences between what is actuallyperceived and the image on theretina. The image is spatiallydistorted through its projectiononto the curved surface of theretina. Through chromatic aber-

E

Perspective

GuideBasics | Seeing and perception | Physiology of the eye

Optical system

Spherical aberration. Projectedimages are distorted due to thecurvature of the retina.

If we perceive objects that arearranged within a space, theperspectives of the images pro-duced on the retina are distorted.A square perceived at an angle,for example, will produce a trap-ezoidal image on the retina. Thisimage may, however, also havebeen produced by a trapezoidalsurface viewed front on. The onlything that is perceived is onesingle shape – the square thatthis image has actually produced.This perception of a square shaperemains consistent, even if theviewer or object move, althoughthe shape of the image projectedon the retina is constantly chang-ing due to the changing perspec-tive.

Chromatic aberration. Images areblurred due to the various degreesof refraction of spectral colours.

Perceptual constancy: percep-tion of a shape in spite of thefact that the image on the retina

is changing with the changingperspective.

ration – light of various wave-lengths is refracted to varyingdegrees, which produces colouredrings around the objects viewed.These defects, however, are elimi-

nated when the image is beingprocessed in the brain.




E GuideBasics | Seeing and perception | Physiology of the eye

Receptors

Receptors There are two different types of receptor: the rods and the cones,which are not distributed evenlyover the retina. At one point, theso-called “blind spot”, there are

no receptors at all, as this is thepoint at which optic nerves enterthe retina.

Receptor density An area of the retina called thefovea is the focal point of thelens. In this area, the concen-tration of the cones is greatest,whereas the density of the conesreduces rapidly outwards to theperiphery. Here we find the great-est concentration of rods, which

do not exist in the fovea.

The older of these two systems,from an evolutionary point of view, is the one consisting of rods.The special attributes of this sys-

tem include high light-sensitivityand a great capacity for perceiv-ing movement over the entirefield of vision. On the other hand,rods do not allow us to perceivecolour; contours are not sharpand it is not possible to concen-trate on objects, i.e. to studyitems clearly even if they are in

Rods

Number N of rods and cones onthe retina in relation to the angleof sight

the centre of our field of vision.The rod system is extremely sen-sitive and is activated when theilluminance level is less than 1 lux.

Our night vision features, particu-larly the fact that colour is notevident, contours are blurred andpoorly lit items in our peripheralfield of vision are more visible– can be explained by the proper-ties of the rod system.

The cones form a system withvery different properties. This isa system which we require to seethings under higher luminousintensities, i.e. under daylight orelectric light. The cone systemhas lower light-sensitivity and isconcentrated in the central areain and around the fovea. It allowsus to see colours and sharpercontours of the objects on whichwe focus, i.e. whose image fallsin the fovea area. In contrast torod vision, we do not perceive theentire field of vision uniformly;the main area of perception is in

the central area. The peripheralfield of vision is also significant,if interesting phenomena areperceived in that area; in thatcase our attention is automati-

Cones cally drawn to these points. Thisis then received as an image onthe fovea to be examined moreclosely. Apart from noticing sud-den movement, striking coloursand patterns, the main reasonfor us to change our direction of view is the presence of high lumi-nances – our eyes and attentionare attracted by bright light.

Relative spectral luminous effi-ciency of rods V and cones V’ inrelation to the wavelength

Spectral colour sensitivity of thecones in relation to the wave-length



19

%LX

3UNLIGHT

/VERCASTSKY

4ASKLIGHTING

#IRCULATIONZONELIGHTING

3TREETLIGHTING -OONLIGHT

,CDM

3UNLIGHT

)NCANDESCENTLAMPMATTFINISH &LUORESCENTLAMP

3UNLIT#LOUDS

"LUESKY ,UMINOUSCEILING

,OUVREDLUMINAIRES

0REFERREDVALUESININTERIORSPACESn7HITEPAPERATLX

-ONITORNEGATIVE n

7HITEPAPERAT LX

,CDM


E GuideBasics | Seeing and perception | Physiology of the eye

Adaptation

Day and night One of the most remarkableproperties of the eye is its abil-ity to adapt to different lightingconditions. We can perceive theworld around us by moonlight or

sunlight, although there is a dif-ference of a factor of 100,000 inthe illuminance. The extent of tasks the eye is capable of per-forming is extremely wide – a

Luminance This ability to adapt to the illumi-nance is only influenced to a verysmall extent by the pupil. Adap-tation is performed to a largedegree by the retina. The rod andcone system responds to differ-ent levels of light intensity. Therod system comes into effect inrelation to night vision (scotopicvision), the cones allow us to seeduring the daytime (photopic

vision) and both receptor systemsare activated in the transitiontimes of dawn and dusk (mesopicvision).Although vision is therefore pos-sible over an extremely wide areaof luminances, there are clearlystrict limits with regard to con-trast perception in each individuallighting situation. The reason forthis lies in the fact that the eyecannot cover the entire range of possible luminances at one and

Adapting from dark to light situ-ations occurs relatively rapidly,whereas adapting from light todarkness requires a considerablylonger time. A good exampleof this is how bright we find itoutside having come out of adark cinema auditorium duringthe daytime or the transitoryperiod of night blindness weexperience when entering a verydark room. Both the fact thatcontrast in luminance can only

Adaptation time

Typical illuminances E and

luminances L under daylight andelectric lighting.

be accommodated by the eyewithin a certain range and thefact that it takes time to adapt toa new level of lighting, or bright-ness, have an impact on lightingdesign. For that reason lightingdesign requires, for instance, thepurposeful planning of differentluminance levels within a spaceor deciding on the adaptation of lighting levels in adjacent spaces.

the same time. The eye adapts tocover one narrow range in whichdifferentiated perception is pos-sible. Objects that possess toohigh a luminance for a particularlevel of adaptation cause glare,that is to say, they appear to beextremely bright. Objects of lowluminance, on the other hand,appear to be too dark.

faintly glowing star in the nightsky can be perceived, although itonly produces an illuminance of 10-12 lux on the eye.

Luminance range L of rod vision(1), mesopic vision (2) and conevision (3). Luminances (4) andpreferred luminances (5) in inte-rior spaces. Absolute threshold of vision (6) and threshold of abso-lute glare (7).)





Psychology of seeing

To understand what visual percep-tion is all about, it is not so muchthe transport of visual informa-tion that is of significance. It israther the process involved in theinterpretation of this information,the creation of visual impressions.The question that arises is whetherour ability to perceive the worldaround us is innate or the resultof a learning process. Another

point to be considered is whethersensory impressions from outsidealone are responsible for theperceived image or whether thebrain translates these stimuli intoa perceivable image through theapplication of its own principlesof order. There is no clear answerto this question. Perceptual psy-chology is divided on this point.

Contour Overall shape Colour




E GuideBasics | Seeing and perception | Psychology of seeing

Contour Experience, and the expectationslinked with it, may be so strongthat missing elements of a shapeare perceived as complete or indi-vidual details amended to enable

the object to meet our expecta-tions. The perception of a shapewith missing contours is simplybased on shadow formation.

Overall shape Experience leads us to recognise

an overall shape by being able toidentify essential details.

Colour This picture illustrates how acolour is matched to the respec-tive pattern perceived. The colourof the central grey point adjustsitself to the black or white colourin the perceived pattern.





Constancy

Fixed objects produce retinalimages of varying shapes, sizesand brightness. Due to changesin lighting, distance or perspec-tive, this indicates that mecha-nisms must exist to identify theseobjects and their properties and toperceive them as being constant.There is no single, simple explana-tion for the way perception works.Optical illusions provide an oppor-

tunity to examine the perform-ance and objectives of perception.

Brightness Luminance gradient Three-dimensionality

Wall structure Beam of Light Perception of colour

Perspective Size




E GuideBasics | Seeing and perception | Constancy

Brightness The fact that a medium greyarea will appear light grey if it isbordered in black, or dark grey if it is bordered in white. This canbe explained by the fact that the

stimuli perceived are processeddirectly – brightness is perceivedas a result of the lightness con-trast between the grey area andthe immediate surroundings.What we are considering here isa visual impression that is basedexclusively on sensory inputwhich is not influenced by anycriteria of order linked with ourintellectual processing of thisinformation.

The perception of brightnessof the grey field depends onthe environment – in brightsurroundings, an identical greyappears darker than in dark sur-roundings.

Luminance gradient The continuous luminance gradi-

ent across the surface of the wallis interpreted as a property of thelighting. The wall reflectance fac-tor is assumed to be constant. Thegrey of the sharply framed pictureis interpreted as a material prop-erty, although the luminance isidentical to the luminance in thecorner of the room.

Three-dimensionality Changing luminance levels mayarise from the spatial form of theilluminated object; examples of this are the formation of typicalshadows on objects such as cubes,cylinders or spheres.

The spatial impression is deter-mined by the assumption thatlight comes from above.

By inverting the picture, the per-ception of elevation and depth isreversed.

The spatial form of an object canbe recognised by the gradient of

the shadows.





Wall structure Irregular or uneven luminancescan result in confusing lightingsituations. This is evident, forexample, when luminous pat-terns created on the walls bear

no relation to the architecture.The observer’s attention is drawnto a luminous pattern that can-not be explained through theproperties of the wall, nor as animportant feature of the lighting.If luminance patterns are irregu-lar, they should, therefore, alwaysbe aligned with the architecture.

The lighting distribution on anunstructured wall becomes adominant feature.

Beam of Light The visible pool of light deter-mines whether it is perceived asbackground or as a disturbingshape. Light distribution that is

not aligned with the shape of thepicture is perceived as a disturb-ing pattern.

The same lighting distribution ona structured wall is interpreted asbackground and not perceived.

Light distribution that is notaligned with the architecturalstructure of the space is perceivedas disturbing patterns that do notrelate to the space.

Perception of colour The perception of colour, similarto the perception of brightness,is dependent on neighbouringcolours and the quality of thelighting. The necessity for us to beable to interpret colours is basedon the fact that colour appear-ances around us are constantlychanging. A colour is thereforeperceived as being constant bothwhen viewed in the bluish lightof an overcast sky or in warmerdirect sunlight – colour photo-graphs taken under the sameconditions, however, show thedistinct colour shifts that wemust expect under the particulartype of light.





Perspective Our misinterpretation of lines of the same length shows that theperceived size of an object doesnot depend on the size of theretina image alone, but that the

distance of the observer from theobject is significant. Vice versa,objects of known sizes are usedto judge distances or to recog-nise the size of adjacent objects.From daily experience we knowthat this mechanism is sufficientto allow us to perceive objectsand their size reliably. Therefore,a person seen a long way awayis not perceived as a dwarf anda house on the horizon not as asmall box. Only in extreme situa-tions does our perception deceiveus: looking out of an aeroplane,objects on the ground appear tobe tiny; the viewing of objects

that are considerably fartheraway, e.g. the moon, is muchmore difficult for us to handle.

In this case the perspective resultsin an optical illusion. The verticalline to the rear appears to belonger than the line of identicallength in the foreground.

Size To allow for the perception of size, we have a mechanism thatbalances the perspective distor-tion of objects. It guarantees that

the changing trapezoidal andellipsoidal forms in the retinaimage can be perceived spatiallyas being normal, rectangular orround objects by being aware of the angle at which the object isviewed.

Constancy with regard to per-ception of size. Due to the per-spective interpretation of thisillustration, the luminaires areall perceived as being the samesize in spite of the variations insize of the retina images.





Perception of gestalt

Before a property can be attrib-uted to an object, the objectitself must be recognised, thatis to say, distinguished from itssurroundings. This process of interpretation has been usedto formulate laws accordingto which certain arrangementsare grouped together to formshapes, i.e. objects of percep-tion. These laws of gestalt are of

practical interest to the lightingdesigner. Every lighting installa-tion comprises an arrangementof luminaires – on the ceiling,on the walls or in the space. Thisarrangement is not perceivedin isolation, but in forms orgroups in accordance with thelaws of gestalt. The architecturalsurroundings and the lightingeffects produced by the lumi-naires produce further patterns,which influence in our perceptionof the space.

Closed form Proximity Inside

Symmetry Shapes of equalwidth

Continuous line

Pure form Identity




E GuideBasics | Seeing and perception | Perception of gestalt

Closed form An essential principle of the per-ception of gestalt is the tendencyto interpret closed forms as pureshapes.

Proximity Elements arranged close togetherare grouped according to thelaw of proximity and form a pureshape. The example on the leftdemonstrates that we first see acircle and then an arrangementof luminaires. The circles arearranged in such a strict order

that the imaginary linking linesbetween them is not straightlines, but forms a continuouscircle, not a polygon.Luminaires are grouped in pairs. Four points are grouped to form

a square.

From eight points on, a circle isformed.

Inside Shapes that are not completelyclosed can also be perceived as agestalt. A closed shape is alwaysseen as being on the inside of the linking line – the formativeeffect therefore only works inone direction. This inner side isusually identical to the concave,surrounding side of the line thatencloses the shape. This in turnleads to a formative effect evenin the case of arcs or angles, mak-ing a pure shape visible inside theline, that is to say, in the partlyenclosed area. If this leads to aplausible interpretation of theinitial pattern, the effect of theinner side can be significant.

An arc makes a pure shape visibleon the inside of the line.





Symmetry In regard to symmetry, the per-ception of a form as a pure shapeis based on simple, logical struc-ture. On the other hand morecomplex structures belonging to

the same pattern disappear intoan apparently continuous back-ground.

Shapes of equal width A similar result occurs in parallel

shapes of equal width. This is notstrictly a case of symmetry. Aprinciple of order and organisa-tion is, however, evident, allowingus to perceive a pure shape. Twoparallel lines show similarity.

Even without strict symmetry,it is possible to recognise a pureshape.

When two square luminaires areadded to the pattern of circulardownlights, the arrangement isperceived according to the lawof symmetry to form two groupsof five.

Continuous line A basic law of gestalt is to preferto perceive lines as steady con-tinuous curves or straight lines,and to avoid bends and kinks.Our preference to perceive con-tinuous lines is so great that itcan influence our overall inter-pretation of an image.

Law of gestalt relating to con-tinuous lines. The arrangement isinterpreted as two lines crossing.





Pure form When it comes to two- dimensional shapes, the law of the continuous line conformswith the law of pure form. Inthis case, shapes are organised to

create figures that are as simpleand clearly arranged as possible.

Identity Besides spatial layout, the struc-

ture of the shapes themselves isalso responsible for their forma-tion into groups. The shapes inthe accompanying drawing arenot organised according to prox-imity or axial symmetry, but ingroups of identical shapes. Thisprinciple of identity also applieswhen the shapes in a group arenot absolutely identical but onlysimilar.Luminaires of the same type are

grouped together.

The downlight arrangement isgrouped into two lines accordingto the law of pure form.

The arrangement is interpreted astwo superimposed rectangles.





Objects of perception

We are not however, consciousof every object that comes withinour field of vision. The way thefovea prefers to focus on small,changing scenes shows that theperception process purposefullyselects specific things to look at.This selection is inevitable, as thebrain is not capable of processingall the visual information in thefield of view. It also makes sense

because not all the informationthat exists in our environment isnecessarily relevant to us.

Activity Information Social



31

M

M

M


E GuideBasics | Seeing and perception | Objects of perception

Activity The value of any particularinformation relates to the cur-rent activity of the observer.This activity may be work ormovement-related or any other

activity for which visual infor-mation is required. Lighting con-ditions under which the visualtask can be perceived to an opti-mum degree can be determinedfrom the above-mentioned spe-cific features. It is possible todefine ways of lighting whichwill be ideal for specific activities.

Visual field (1), preferred visual

field (2) and optimum field of vision (3) of a person standingand sitting for vertical visualtasks

Preferred field of vision for

horizontal visual tasks. Preferredangle of view 25°

Information There is another basic need forvisual information that goesbeyond the specific informationrequired for a particular activity.

This is not related to any particu-lar situation, it results from man’sbiological need to understand theworld especially man’s need tofeel safe. To evaluate danger, wemust be aware of the structureof the environment. This appliesto orientation, weather ,time of day and information relating toother activities occurring in thearea. If this information is notavailable, e.g. in large, windowless

Social In regard to man’s social needs –the need for contact with otherpeople and the need for privatespace are somewhat contradic-tory and require careful balance.The focus on which visual infor-mation is required is determinedby the activities and basic biologi-cal needs. Areas likely to providesignificant information – on theirown or by being highlighted - areperceived first. They attract ourattention. The information con-tent of a given object is respon-sible for its being selected as anobject of perception. Importantly,

buildings, the situation is oftenconsidered to be unnatural andoppressive.

the information content influ-ences the way in which an objectis perceived and evaluated.




GuideDesigning with light

E

Light plays a central role in thedesign of a visual environment.The architecture, people andobjects are all made visible bythe lighting. Light influences ourwell-being, the aesthetic effectand the mood of a room or area.

Architectural lighting Planning process Practical planning

Visualis ing l ight




E GuideDesigning with light

Architectural lighting

Lighting interiorspaces

Connecting spaces Illuminate objects

Design with colouredlight

It is light that first enables spatialperception. Above and beyondthis, our perception of architec-ture can also be influenced withlight: it expands and accentuatesrooms, creates links and deline-ates one area from another.




Forming functionalzones

Defining spatialborders

Emphasising archi-tectural features

E GuideDesigning with light | Architectural lighting

Lighting interior spaces

Light can alter the appearanceof a room or area without physi-cally changing it. Light directsour view, influences perceptionand draws our attention to spe-cific details. Light can be usedto divide and interpret roomsin order to emphasise areas orestablish continuity between theinterior and exterior. Light distri-bution and illuminance have a

decisive influence on how archi-tecture is perceived.




E GuideDesigning with light | Architectural lighting | Lighting interior spaces

Forming functional zones

Light can be used to emphasiseindividual functional zones inan area, e.g. traffic areas, wait-ing areas, and exhibition areas.Zonal lighting with delineated

beams of light visually separatesone area from another. Differentilluminance levels establish a per-ceptual hierarchy and direct theviewer’s gaze. The differentiationof light colours creates contrastsand emphasises individual zones.

Differentiated lighting of func-

tional zones divide up an area andimprove orientation. Areas of aspace can be separated from eachother using narrow beams of lightand strong contrasts in bright-ness. Distinct contrasts betweenindividual zones and their sur-roundings remove them fromtheir spatial context. Large areasthat on the whole are evenly illu-minated can appear rather mono-tone if they are not divided up.Low general lighting provides thebasis for adding lighting accents.Lighting control systems allowfunctional zones to be adapted todifferent uses.

Observation

Conclusion

Applications

Projects:Private home, New South WalesHeart of Jesus Church, MunichTeattri Ravintola, HelsinkiERCO, Lüdenscheid





Defining spatial borders

Floor illumination emphasisesobjects and pedestrian surfaces. Vertical spatial borders areemphasised by illuminating wallsurfaces. Uniform light distribu-

tion emphasises the wall as awhole, whereas accentuating,grazing light gives the wall struc-ture by adding patterns of light.Bright walls create a high levelof diffuse light in the room.

Vertical il lumination is used to

shape the visual environment.Room surfaces can be differ-entiated using different levelsof illuminance to indicate theirimportance. Uniform illumina-tion of the surfaces emphasisesthem as an architectural feature.A decreasing level of brightnessacross a wall is not as effective asuniform wallwashing at definingroom surfaces. Lighting effectsusing grazing light emphasisethe surface textures and becomethe dominant feature. Indirectlighting of a ceiling creates dif-fuse light in the room with thelighting effect being influencedby the reflectance and colour of its surface.

Observation

Conclusion

Applications

Projects:Conrad International Hotel,SingaporeLamy, HeidelbergEzeiza Airport, Buenos AiresLight and Building, Frankfurt

Wall bright Wall dark





Emphasising architectural features

The illumination of architecturaldetails draws attention away fromthe room as a whole towardsindividual components. Columnsappear as silhouettes in front of

an illuminated wall. Narrow-beam downlights emphasise theform of the columns. Grazinglight accentuates individual ele-ments or areas and brings outtheir form and surface texture.

Rooms can be given a visual

structure by illuminating thearchitectural features. By usingdifferent levels of illuminance,different parts of a room can beplaced in a visual hierarchy. Graz-ing light can cause highly three-dimensional features to caststrong shadows.

Observation

Conclusion

Applications

Projects:Tokyo International ForumInternational Hotel, SingaporePalacio de la Aljaferia, ZaragozaCatedral de Santa Ana, Las Palmas




Inside – lookinginside

Inside – lookingoutside

Outside – lookinginside

Outside – lookingoutside


Connecting spaces

Combining rooms can createcomplex architectural patterns.Light interprets these in terms of their structure and orientation.Targeted lighting enables theviewer to look into an area andcreates spatial depth. The con-sideration of material qualitiesin combination with the correctilluminance, colour of light andlight distribution is an important

aspect in the design stage.




E GuideDesigning with light | Architectural lighting | Connecting spaces

Inside – looking inside

The bright rear wall gives theroom depth and accentuates thespatial perspective. Illuminatedobjects in the background achievea similar effect. If the emphasis

of the illuminance level is shiftedfrom the back to the front areaof the room, then the focus of attention will also shift from thebackground to the foreground.

Observation

Light makes surfaces or objects

visible and allows them tobecome the focus of attention.Dark spatial zones cause spatiallimits to disappear and recedeinto the background. Differenti-ated spatial lighting can producea hierarchy of how spaces areperceived. Illuminating verticalsurfaces is of particular creativeimportance for the design sincea better effect is achieved as theresult of spatial perspective thanwhen illuminating horizontalsurfaces.

Conclusion

Applications

Projects:Museum Georg Schäfer,SchweinfurtCatedral de Santa Ana, Las PalmasDZ Bank, BerlinGuggenheim Museum, Bilbao





Inside – looking outside

A high illuminance level in theinterior combined with a darkexterior creates a strong reflec-tion on the facade plane. Theinterior visually appears to double

in size from the exterior due tothe reflection. Objects in the out-door area are not recognisable.As the illuminance level in theinterior decreases and the lumi-nance in the exterior increases,the mirror effect is reduced andobjects on the exterior becomerecognisable.

Observation

Conclusion The reflection on the glass

becomes less as the luminancein front of the glass decreasesand the luminance behind theglass increases. Well shieldedluminaires in front of the glassplane cause less reflection. Lowerilluminance in the interior allowsbetter perception of the exterior.When directing luminaries onthe exterior, direct glare into theindoor area should be avoided.

Applications

Projects:Miho Museum, OsakaHarvey Nichols Restaurant,LondonPrivate home, New South WalesABN AMRO, Sydney





Outside – looking inside

The high illuminance level of day-light causes a strong reflectionon the glass surface. Objects inthe indoor area are not percept-able. As the illuminance level

in the outdoor area decreases,the reflection becomes less. Thisallows illuminated objects orsurfaces in the indoor area tobecome visible. The glass is nolonger perceptible.

Observation

Conclusion The reflection on the glass

becomes less as the luminance infront of the glass decreases andthe luminance behind the glassincreases. Luminaires in front of the glass that are well shieldedand integrated into architecturecause less reflection of them-selves. A low illuminance levelin the indoor area produces adeep spatial effect at night. Theillumination of objects in indoorareas – such as shop windows– requires very high illuminanceto make these objects visible dur-ing the day due to the high illu-minance level outside. Adjustingthe indoor lighting to the chang-ing daylight is recommendable.A higher illuminance level duringthe day and a low level in theevening reduces the contrast.Applications

Projects:Lamy, HeidelbergRitz-Carlton, Singapore“Dat Backhus” bakery, HamburgBlue Lagoon Spa, Reykjavik





Outside – looking outside

A bright rear wall lends depth tothe room and helps delineate theroom limits. Illuminated objects inthe background achieve a similareffect. If the emphasis of the

illuminance level is shifted fromthe back to the front area of theroom, then the focus of attentionwill also shift from the back-ground to the foreground.

Observation

Conclusion Light makes surfaces or objects

visible and brings them into theforeground. Dark zones of theroom make the room limits dis-appear and the effect of areasrecedes into the background. Dueto the low illuminance level atnight, the required illuminancesare less than for indoor lighting.

Applications

Projects:Hong Kong Convention andExhibition CentreMiho Museum, OsakaFederal Chancellery, BerlinPrivate home, Milan




E

Light directs our view and focusesthe attention on details. The direc-tion of light, illuminance and thelight distribution all determinethe effect of an object in its sur-roundings.

GuideDesigning with light | Architectural lighting

Illuminate objects

Direction of light Vary the lightdistribution

Accentuate objects




E

Directed light from the frontproduces a strong modelling abil-ity. Light from above causes theobject to cast strong shadows onitself. Light from behind creates

a silhouette. The steeper the inci-dent light, the more pronouncedthe shadow effect.

Observation

Conclusion If the light from the front is alsocoming slightly from one side, itgains a strong descriptive power.Light that is solely head-onhardly causes any shadow in thedirection of vision and the objectloses some of its 3-dimensionalappearance. Very steep incidentlight is suitable for objects having

a very shallow texture in order tomake them more 3-dimensional.

GuideDesigning with light | Architectural lighting | Illuminate objects

Direction of light




Applications

Projects:Pinacoteca Vaticana, RomeGuggenheim Museum, BilbaoHermitage, St. PetersburgHermitage, St. Petersburg

Arrangement The steeper the incident light, themore pronounced the shadoweffect. Objects can be illuminatedwell when the direction of light isbetween 5° and 45° to the verti-

cal. The optimal direction of lightfor illuminating objects is at 30°.This avoids strong reflected glareor undesirable shadows on peopleor objects.

E GuideDesigning with light | Architectural lighting | Illuminate objects

Direction of light

Highlighting is used for modellingobjects in:- museums- exhibitions

- salesrooms

Preferred luminaire groups- spotlights- floodlights





Vary the light distribution

Narrow-beam spotlights accentu-ate the object and make it standout against the surroundings. Thebeam of light is stretched into anoval using a sculpture lens. Flood

lenses spread out the narrowbeam and create a soft brightnessgradient.

Observation

Conclusion The narrower the beam of lightcast on the object, the strongerthe effect. Sculpture lenses areparticularly suitable for project-ing light at objects over theirentire height. With their widelight beam, flood lenses illumi-nate the surroundings stronger

and represent the object in itsspatial relationship.

Spotlights

Sculpture lens

Flood lens

Applications

Projects:Bunkamura Museum of Art, TokyoMuseo del Prado, Madrid Vigeland Museum, NorwayHermitage, St. Petersburg

Highlighting is used for modellingobjects in:- museums- exhibitions- salesrooms

Preferred luminaire groups- spotlights with accessories





Accentuate objects

The objects and the wall are givengeneral lighting by wallwashers.Beams from individual spotlightsadd emphasis to the objects.A higher brightness contrast

increases the level of accentua-tion.

Observation

Conclusion When the brightness contrastof the ambient surroundings tothe object is 1:2, a contrast canhardly be noticed. When the ratiois 1:5, a minimum brightnesscontrast is established betweenprimary and secondary points of interest. A contrast of 1:10 brings

out the difference very well. Abrightness contrast of 1:100detaches the object very stronglyfrom its ambient surroundingsbut an unintentional dissectionof the wall can arise.

1:1

1:5

1:10

Applications

Projects:Museo Ruiz de Luna Talavera,SpainGerman Architectural Museum,FrankfurtGuggenheim Museum, BilbaoMuseo Picasso, Barcelona

Highlighting of objects on walls isa practice used in:- museums- exhibitions- trade-fair stands- salesrooms





Design with coloured light

Colour is a significant componentof visual perception. It cannotbe perceived without daylight orartificial lighting. The combina-tion of lamps and filters allowsa multitude of design possibili-ties for emphasising or alteringthe lighting effect of rooms andobjects with coloured light. Theterm “colour of light” covers bothwhite and coloured light. Warm

white, neutral white and daylightwhite are derived from the whitecolour of light. The coloured lightcovers the entire visible spectrum.

Colour Colour systems Colour of light

Colour mixing Colour rendition Colour effect

Colour contrast Ambient colours Coloured highlighting




E GuideDesigning with light | Architectural lighting | Design with coloured light

Colour

The light colour refers to a colourwhich is emitted by a light source.The light colour is produced as aresult of the emitted spectrumof light. The type of light colour

is defined by hue, saturation andbrightness. Using filters producescoloured light. This enables thecolouration of rooms to be modi-fied without changing the roomsphysically. Mixing several lightcolours is referred to as additivecolour mixing.

Light colour

The body colour arises as a resultof the incident light and the spe-cific absorption properties of thesurface. Therefore, the tri-stimu-lus value of a body colour canonly be determined in combina-tion with the type of light withwhich it is illuminated. In additionto hue, brightness and saturation,the body colour of an object isalso defined by the reflectance.When illuminating coloured wallsor objects with coloured light, thereciprocal effect of light colourand body colour is paramount.This interplay is the basis of sub-tractive colour mixing. The chro-matic effects can be intensifiedor altered.

Body colour





Colour systems

In the CIE standard colorimetricsystem, body colours and lightcolours are represented in acontinuous, two-dimensionaldiagram. The spectral constitu-

tion of light colours results fromthe type of light, while that of body colours results from thetype of light and the spectralreflectance or transmittance. Thedimension of brightness is leftunconsidered here; this meansthat only the hue and saturationof all colours can be determinedin the diagram. The coloured areais enclosed by a curve on whichthe chromaticity locations of thecompletely saturated spectral col-ours lie. At the centre of the areais the point of least saturation,which is designated as a whiteor uncoloured point. All levels of

saturation of one colour can nowbe found on the straight linesbetween the uncoloured pointand the chromaticity location inquestion. Similarly, all mixturesof two colours are likewise to befound on a straight line betweenthe two chromaticity locations inquestion. Complementary coloursare located opposite each otherin the CIE model and combine toform white.

CIE system

In the Munsell system, bodycolours are arranged accordingto the criteria of brightness,hue and saturation to producea complete sample catalogue inthe form of a three-dimensionalmatrix. Brightness here refers tothe reflectance of a body colour;the hue refers to the actual col-our, while the term saturationexpresses the degree of colora-tion, from the pure colour downto the uncoloured greyscale.Whereas a two-dimensional dia-gram is sufficient for colours of light, a three-dimensional systemis required for body colours dueto reflectance.

Munsell system





Colour of light: White light

The higher red component inwarm white light allows rooms toappear warmer than with neutralwhite light. The higher blue com-ponent in daylight white light

creates a cooler atmosphere.

Observation

On presentation lighting, makingspecific use of colours of lightallows luminous colours to beachieved on the objects beingilluminated. Daylight white lightis often used in office rooms toaugment the daylight.

Conclusion

Applications

Projects:Sony Center, BerlinGlass pavilion, Glass technicalcollege, RheinbachHong Kong and Shanghai BankERCO, Lüdenscheid

Warm colours of light are pre-

ferred above all at lower illumi-nances and with directed light,whereas cold colours of light areaccepted at high illuminancesand diffuse illumination. Whitelight is described by specifyingthe colour temperature, colourrendition, chromaticity locationand spectrum. The white colourtemperature is divided into threemain groups: warm white, neutralwhite and daylight white. A goodcolour rendition with the lightingwill only produce a low colourdeviation. The chromaticity loca-tion identifies the colour withinthe CIE diagram.





Colour of light: Coloured light

Compared to the primary coloursyellow, blue and red, the coloursamber and magenta appearweaker in their expressiveness.Yellow and red colours of light

create a warm atmosphere in aroom. Blue colours of light allowa room to give a cooler impres-sion.

Observation

In architectural lighting, colours

from the daylight spectrum arefelt to be natural: magenta (con-ditions of light at sunset), amber(atmospheric light at sunrise),night blue (clear night sky) andsky blue (light of the sky by day).For coloured light, the data con-cerning chromaticity locationand spectrum are important. Thechromaticity location is speci-fied by the co-ordinates in theCIE diagram, whereby a colour of light can be formed by differentcolour spectra.

Conclusion

Applications

Projects:ERCO P3, LüdenscheidZürich Insurance, Buenos AiresTeattri Ravintola, HelsinkiTeattri Ravintola, Helsinki

Coloured light is used for- exhibitions- trade-fair stands- salesrooms- event lighting





Colour mixing: Colours of light

Super imposing several colours of light is an additive mixing proc-ess. Mixing two of the primarycolours red, green and blue resultsin magenta, cyan or yellow. By

mixing the three primary coloursin equal amounts, white light isproduced.

Observation

When illuminating objects with

differently coloured light sources,the spatial superimposition givesrise to interesting additive colourmixing effects, which may eveninclude coloured shadows.

Conclusion





Colour mixing: Light colour and body colour

Subtractive colour mixing occurswhen coloured surfaces areilluminated with coloured light.Mixing two of the subtractiveprimary colours magenta, cyan

and yellow, produces the addi-tive primary colours red, greenor blue. Warm body colours areemphasised by a warm whitecolour of light. Cold body coloursappear brighter and more satu-rated under cold neutral coloursof white light, especially daylightwhite.

Observation

The appearance of a body colour

can seem more saturated andbrighter when the lighting on itis of similar colour. Body coloursappear less saturated, or darker,when the coloured lighting is dis-similar. The actual appearance of the results of subtractive colourmixing depends on the spectralconstitution of the componentsbeing mixed.

Conclusion

Applications

Projects:Shop Colette, ParisGreater London AuthorityTeattri Ravintola, HelsinkiERCO Trade Fair, Hanover

In practice, when illuminatingcoloured surfaces, it is recom-mendable to perform lightingtests or calculations. The sameapplies to the use of colour filters.

Wall: BlueLight: Warm white

Wall: BlueLight: Blue

Wall: BlueLight: Magenta

Wall: BlueLight: Yellow



55

100

80

60

20

0

40

800

%

400 500 700600 nm300

%100

80

60

20

0

40

800400 500 700600 nm300



Colour rendition

The quality of the reproductionof colours is termed colour rendi-tion. Linear spectra have a verygood colour rendition. Linearspectra only permit one single

colour to be perceived well. Mul-tiline spectra reproduce severalcolours of the relevant spectrumwell, but in the intermediate are-as the colour rendition is weaker.Blue and green colours appearcomparatively grey and mattunder warm white incandescentlight despite excellent colourrendition. However, these huesappear clear and bright underdaylight white light from fluo-rescent lamps – despite poorercolour rendition. When renderingyellow and red hues, this phe-nomenon of respective weakeningand intensifying of the chromatic

effect is reversed.

Observation

Incandescent lamp

Continuous spectra lead to goodcolour rendition. Incandescentlamps or daylight have the colourrendition index Ra 100.

DaylightContinuous spectra lead to goodcolour rendition. Incandescentlamps or daylight have the colourrendition index Ra 100.



56

%100

80

60

20

0

40

800400 500 700600 nm300


Because the eye is able to adaptto light of the most differentcolour temperatures, the colourrendition must be determineddependent on the colour tem-

perature. Tungsten halogenlamps feature very good colourrendition. The rendition qualityof fluorescent lamps and metalhalide lamps ranges from goodto average. The degree of colourdistortion against a referencelight source is indicated using thecolour rendition index Ra or thecolour rendition grading system.The colour rendition index is onlyused for white colours of light.

Conclusion

Fluorescent lamp

Discharge lamps such as fluores-cent lamps or metal halide lampsfeature a multiline spectrum.Their colour rendition is thereforelower than Ra 100.


Colour rendition

Physics The same colours of light canproduce a different rendition of a body colour due to differentspectral constitution. Continuous

spectra lead to a unifrom colourrendition. Linear spectra only cor-rectly render a very small colourrange. Multiline spectra are com-piled from different linear spectraand thus improve the colour ren-dition. The more spectra can bebound to one linear progression,the better the colour rendition.Incandescent lamps feature alinear spectrum, while dischargelamps have a multiline spectrum.

Linear spectrum Continuous spectrum Multi line spectrum

Applications

Very good colour rendition isimportant for- exhibitions

- trade-fair stands- salesrooms- offices- workstations





Colour effect

- Red is the colour of fire andthe expression for power, warmthand energy. The colour has adominant effect. Where palered is concerned, the aspect of

warmth decreases while its light-ness increases.- Yellow is the lightest colour inthe colour wheel, but used in theforeground it does not have thesame energy as red.- Blue is the colour of the sky andis one of the cold colours whichgives an effect of depth. Darknavy blue has a rather melan-choly effect, whereas blue-greenemanates peace.- Green is the colour of vitality.Its nuances range from calmingto refreshing.- White is one of the non-coloursand is the polar opposite of black.

White stands for purity.- Black stands for darkness andappears sinister and negative.- Grey is one of the non-coloursand appears indifferent.

Observation

The effect of colours is explained

from the physiological point-of-view of actually seeing colour andthe psychological aspects of sen-sory perception. The lure of col-ours triggers associations and isinterpreted in the context of thesocial and cultural environment.The different hues belonging toa colour can, in turn, also haveother effects. The effect of indi-vidual colours can be increased byway of a colour contrast.

Conclusion

Applications

Projects:Saab City, LondonLight and Building 2000,FrankfurtRestaurant Aioli, ViennaTeattri Ravintola, Helsinki

Colour effects are particularlyimportant for- exhibitions- trade-fair stands- sales areas- restaurants





Colour contrast

The seven colour contrasts origi-nated from the colour theory of Johannes Itten. This approach isnot based on physical and chemi-cal properties of colours, but on

their subjective effects.

The primary colours yellow, redand blue produce the strongestcontrast. The colour contrastbecomes weaker with secondaryor tertiary colours or as the satu-ration decreases.

Colours themselves

The “non-colours” black and

white produce the strongestcontrast. Even with the “proper”colours, their effect is significant.A light colour next to a darkcolour has a stronger effect thannext to an equally light or lightercolour. The effect of hues can beintensified by greater differencesin brightness.

Light-dark

In the colour wheel, the warmcolours with red and yellow com-ponents are located opposite tothe cold blue hues. Green andmagenta form the neutral transi-tions. The effect of a predominantcolour can be increased whencombined with an accent fromthe opposite colour.

Cold-warm

WarmCold





Colour contrast

The effect of the simultaneouscontrast has its origin in how theeye processes perception. Afterstaring at a colour for a long timeand then looking at a neutral

grey, the eye forms a simultane-ous contrast colour. Red leads toa green tinged grey shade. Greencauses a grey area with a redtinge to appear. Colours changetheir effect due to the influenceof the surrounding colours.

Simultaneous

The pairs of colours lying oppo-site in the colour wheel form thecomplementary contrast from aprimary colour and the secondary(mixed) colour made of the othertwo primary colours. Yellow-vio-let displays the largest light-darkcontrast, orange-blue the largestcold-warm contrast. Red-greenhave the same light intensity. Thecomplementary contrast causes

the brilliance of the colours toincrease.

Complementary





Colour contrast

The quality contrast, or intensitycontrast, describes the distinctionbetween pure colours and murkycolours. Mixing pure colours withgrey shades makes the former

murky and dull, and the quality of colour purity is lost. Pure colourshave a dominating effect overmurky colours.

Quality

The quantity contrast refers to

the relationship of the size of onecoloured area with the next. Alarge coloured area with a smallarea in a contrast colour increasesthe chromatic effect of the maincolour.

Quantity





Ambient colours

White light that is reflected by acoloured surface takes on the col-our of the surface and becomesthe predominant colour of lightfor the whole room. When light-

ing a coloured wall with colouredlight, this effect can be increased,reversed or inverted.

Observation

The colour of light in a room isinfluenced by the decoration of the room. In comparison to dif-fuse light, direct light increasesthe effect of the light when illu-minating a coloured surface. Theeffect of a body colour can beintensified by using coloured lightof a similar colour. Strong colourcontrasts appear brighter for thesame illuminance than a weaker

colour contrast. Lesser colourcontrasts can be perceived better

Conclusion under brighter lighting. Withinclosed rooms the effect is hardlyperceptible due to the phenom-enon of colour constancy.

Wall: YellowWhite light: Warm white

Wall: RedColoured light: Magenta

Wall: WhiteColoured light: Amber

Wall: YellowColoured light: Sky blue

Applications

Projects:Polygon Bar, LondonGreater London AuthorityTennispalatsi Cultural Museum,HelsinkiApropos Cöln Concept Store,Cologne

In practice, when illuminatingcoloured surfaces, it is recom-mended that lighting tests orcalculations be carried out.

Coloured accent lighting isused for- exhibitions- trade-fair stands- sales areas





Coloured highlighting

Coloured accent lighting andcoloured background lightingchanges the effect of objects inthe room. The colour saturationof the object increases in the

foreground when the backgroundbrightness is decreased. Bluecolours seem to recede into thebackground, while the chromaticeffect makes magenta come tothe fore.

Observation

Lighting effects can be intensifiedusing coloured light. Strong col-our contrasts increase the bright-ness contrasts. High brightnesscontrasts likewise increase thecolour contrasts. Natural overalleffects arise due to warm coloursof light and filter colours such as“Skintone”, magenta and amber,or due to cold colours of lightsuch as sky blue and night blue.

Conclusion

Wall: WhiteStele: Night blue

Wall: MagentaStele: White

Wall: AmberStele: Magenta

Wall: Sky blueStele: Amber

Applications

Projects:Museo de Bellas Artes, BilbaoZürich Insurance, Buenos AiresTeattri Ravintola, HelsinkiLight and Building 2002,Frankfurt

Coloured accent lighting isused for- exhibitions- trade-fair stands- sales areas




GuideDesigning with light

Planning process

E

The planning process provides anoverview of the sequence of theindividual tasks in lighting design.This process is closely linked withthe planning procedure for anarchitectural design. The findingsof the analysis are firstly chan-nelled into the concept planningand are then finalised for imple-mentation in the design. In addi-tion, maintenance schedules are

a prerequisite for maintaining thequality of light on site.




E GuideDesigning with light | Design practice

Project analysis

The basis for every lighting designconcept is an analysis of theproject; the tasks the lighting isexpected to fulfil, the conditionsand special features. A quantita-

tive design concept can to a largeextent follow the standards laiddown for a specific task. Stand-ards dictate the illuminance level,the degree of glare limitation, theluminous colour and colour ren-dering. When it comes to quali-tative planning, it is necessaryto gain as much information aspossible about the environmentto be illuminated, how it is used,who will use it and the style of the architecture.

A central aspect of project analy-sis is the question of how thespaces that are to be illuminatedare used; it is important to estab-lish what activity or activitiestake place in the environment,how often and how importantthey are. This comprehensiveanalysis of the task gives rise toa series of individual visual tasks,the characteristics of which must

in turn also be analysed. Twocriteria relating to a visual taskare the size and contrast of thedetails that have to be recordedor handled; there then followsthe question of whether colouror surface structure of the visualtask are significant, whethermovement and spatial arrange-ment have to be recognized orwhether reflected glare is likely tobe a problem. The position of thevisual task within the space andthe predominant direction of viewmay also become central issues.

Introduction

Utilisation of space




E GuideDesigning with light | Design practice

Project analysis

From the point of view of archi-tecture and ambience, a buildingor space should be made visible,its characteristics accentuatedand its ambience underlined. Thisrequires detailed information onthe architecture and on the over-all architectural concept com-plete with the intended indoorand outdoor effect by day andnight, the use of daylight and the

permissible energy consumption.This also includes informationon materials, reflectance and thecolour scheme. In Architecturallighting it’s not primarily aboutthe lighting which emphasisesthe building structures and char-acteristic features for a particularperspective, but rather how tocreate the required aestheticeffect in a space. The questionof the building shape, of spatialshape, modules and rhythmicalpatterns, which can be identifiedand expressed by light and lumi-naires – constitutes the centralissue.

Architecture and ambience

Psychological requirements The psychological requirementsinclude perception of the widersurroundings to establish thetime of day, the weather and tofacilitate spatial orientation. In

large buildings frequented by dif-ferent users, the need for visualguidance can become a impor-tant issue. An orderly and clearlystructured environment contrib-utes to the general feeling of wellbeing. Differentiated lightingcan provide spatial delineationfor areas with separate functions.Where there are conversationalzones within larger areas, it maymake sense to create privateareas by using suitable lighting.




E

Lighting concepts list the proper-ties that lighting should possess.They give no exact informationabout the choice of lamps orluminaires or about their arrange-

ment. Project analysis provideslighting quality guidelines givinginformation about the individualforms of lighting. These relateto the quantity and variousquality features of light, andalso gives the degree of spatialand temporal differentiation. Apractical design concept requiresconsultation with the othertrades involved. It must meetthe specifications of the relevantstandards and take both invest-ment costs and running costsinto consideration. The challengeof a qualitative lighting design isto develop a design concept that

combines the technical and aes-thetic requirements of complexguidelines. A concept that deliv-ers the required performance witha commensurate level of techni-cal expertise and the highest levelof artistic clarity will produce themost convincing solution.

In the design phase, decisionsare made regarding the lampsand luminaires to be used, thearrangement and installation of the luminaires and any requiredcontrol gear and control devices.This also allows a reliable calcula-tion of illuminance and costs.No strict process can be set out,nor even one describing gener-ally routine design stages. Thedecision regarding lamp type canbe made at the beginning of aproject or left until an advancedplanning stage; luminaire arrange-ment can be determined by thechoice of a certain luminaire orcould be the criteria for luminaireselection. Lighting design shouldbe seen as a cyclical process inwhich developed solutions arerepeatedly compared to thestated requirements.

Design

GuideDesigning with light | Design practice

Lighting concept




E

A wide range of luminaire types– e. g. spotlights and light struc-tures - are exclusively designedto be installed as additive ele-ments. They may be mounted

on track or lighting structures,suspended from the ceiling(pendant luminaires) or surfacemounted onto the wall or ceil-ing. The range of downlights andlouvered luminaires available isso vast and their designs differsubstantially, which means thatnumerous modes of installationare required. In the case of wallor floor mounting the luminairesmay be surface-mounted orrecessed into the fabric of thebuilding. Ceiling mounting allowsa variety of possibilities: recessedmounting, surfaced mounting orpendant mounting. The Installa-

tion Instructions for the lumi-naires explain the installationand maintenance of the lumi-naires in detail.

The maintenance of a lightinginstallation generally compriseslamp replacement and thecleaning of the luminaires, and

possibly also re-adjustment orrealignment of spotlights andmovable luminaires. The mainobjective of maintenance is toensure that the planned illumi-nance is maintained, i. e. to limitthe unavoidable reduction of luminous flux of a lighting instal-lation. The reasons for the reduc-tion in luminous flux may bedefective lamps and the gradualloss of luminous flux by the lampsor a decrease in light output dueto soiling of the reflectors orattachments. In order to avoida reduction in luminous fluxall lamps must be replaced andluminaires cleaned at regularintervals. Qualitative aspects mayalso be decisive for maintenance.When one lamp in a geometricalarrangement of luminaires failsit may have a detrimental effecton the overall illuminance in thespace. The task of the lightingdesigner is to draw up a main-tenance plan that meets therequirements of the given situa-tion and includes the necessaryinformative literature.

Maintenance

GuideDesigning with light | Design practice

Installation





Practical planning

Having completed the projectanalysis and developed a lightingconcept, the next phase entailspractical planning: decisionsregarding the lamps and lumi-naires to be used, the arrange-ment and installation of the lumi-naires. A detailed design can bedeveloped from a concept basedprimarily on lighting qualities.

Choice of lamps

Mounting

Luminaire selection

Maintenance

Luminaire arrange-ment



69

I

I

I

l

I

Oe (W/klm)

UV Light

0,05-0,10 5-7

0,10-0,15 5-6

0,05-0,15 3-5

0,20-1,00 2-3


E GuideDesigning with light | Practical planning

Choice of lamps

Selecting the right lamp for theluminaire depends on the actuallighting requirements. For thesuccessful implementation of a lighting concept the physicalaspects, such as colour rendition,and the functional criteria aredecisive.Modelling Colour rendition Light colour

Luminous flux Economy Radiant emission



70

LED

A

QT (12V)

QT, QPARTC

T

HIT

HST

Ra10080604020

TF (K)60005000400030002000

LED

A

QT (12V)

QT, QPAR

TC

T

HIT

HST



Choice of lamps

Modelling and brilliance areeffects produced by directedlight. Compact light sources suchas low-voltage halogen lamps ormetal halide lamps are a prereq-

uisite for this. When illuminatingsculptures, presenting merchan-dise or lighting interestinglytextured surfaces, the modellingability and brilliance are of cen-tral importance.

The colour rendition of the lightsource is determined by theactual lamp spectrum. A continu-ous spectrum ensures the optimal

colour rendition. Linear or bandspectra generally worsen the col-our rendition. A very good colourrendition quality is produced byincandescent lamps includingtungsten halogen lamps.

Colour rendition

The light colour of a lampdepends on the spectral distri-bution of the emitted light. Inpractice, the light colours arecategorised into warm white,neutral white and daylight white.Warm white lamps emphasise thered and yellow spectral range,whereas blue and green, i.e. coolcolours, are accentuated underdaylight white light.

Light colour

Modelling

Ranges of the colour renditionindex Ra for different lamp types

Ranges of colour temperature TFfor different lamp types



71

h(lm/W)10080604020

LED

A

QT (12V)

QT, QPAR

TC

T

HIT

HST

50000 t (h)100008000600040002000

LED

A

QT (12V)

QT, QPAR

TC

T

HIT

HST

Lamp Oe (W/klm)

UV Light IR

A, R, PAR 0,05-0,10 5-7 35-60

QT 0,10-0,15 5-6 25-30

T, TC 0,05-0,15 3-5 6-10

HME 0,20-1,00 2-3 10-15

HIT 0,20-1,00 2-5 6-10

HSE 0,01-0,05 2-3 4-6

1000 P (W)500400300200100

LED

A

QT (12V)

QT, QPAR

TC

T

HIT

HST

50000 F (lm)2000 5000 1000010005001005010

LED

A

QT (12V)

QT, QPAR

TC

T

HIT

HST



Choice of lamps

The economy of a lamp dependson the luminous efficacy, thelamp life and the cost of thelamp. Incandescent lamps andtungsten halogen lamps havethe lowest luminous efficacies.Clearly larger values are attainedby fluorescent lamps, high pres-sure mercury vapour lamps andmetal halide lamps. Incandescentlamps and tungsten halogenlamps have the lowest lamp life.The life of fluorescent lamps andhigh-pressure lamps is consider-ably higher.

Economy

Ranges of luminous efficacy η fordifferent lamp types

Ranges of service life t fordifferent lamp types

Aspects of radiation are impor-tant in the field of exhibition anddisplay. Infrared and ultravioletradiation can cause damage onpaintings. High proportions of infrared radiation and convec-tion heat are emitted above all bylight sources with low luminousefficacy, such as incandescentlamps or tungsten halogen lamps.With conventional and compactfluorescent lamps the infraredradiation is noticeably lower. Thedamaging infrared and ultravioletcomponents can be reduced con-siderably by using filters.

Radiant emission

Particularly small luminous fluxvalues are primarily found withLEDs and low-voltage halogenlamps, followed by conventionalincandescent lamps and compact

fluorescent lamps. Conversely,tungsten halogen lamps formains voltage, fluorescent lampsand high-pressure dischargelamps all feature particularly highluminous flux values; the high-est values are attained by metalhalide lamps.

Luminous flux

Ranges of power P for differentlamp types

Relative radiated power φe of different lamp types, with respectto a luminous flux of 1000 lm,subdivided into the wavelengthranges: UV (280 nm-380 nm),visible light (380 nm-780 nm),IR (780nm-10000 nm).

Example: φe = UV · lm / 1000An A60 lamp with 100W and1380 lm results in a UV radiatedpower of 0.069-0.138 W.

Ranges of luminous flux F fordifferent lamp types





Luminaire selection

The choice of light sources out-lines the technical qualities of the lighting design concept andthe limits to the lighting qualitiesthat can be achieved. The light-ing effects that can be obtainedwithin this range depend on thechoice of luminaires in which thelamps are to be used. The choiceof lamp and luminaire is there-fore closely related. Opting for a

particular light source will reducethe choice of luminaire, and viceversa, the choice of luminaire willrestrict the choice of lamp.

Light distribution Luminous colour Methods of mounting

Luminance Illuminance Safety requirements




E GuideDesigning with light | Practical planning | Luminaire selection

Light distribution

Uniform general lighting is astandard lighting concept. Forgeneral lighting, wide-beamluminaires such as downlightsand light structures are suitable.

Uniform lighting can also beachieved by indirect illumination.However, a lighting concept thataims solely to create isolatedlighting accents is the exception.Often, accent lighting will containgeneral lighting components toallow the viewer to perceive thespatial arrangement of the illumi-nated objects. Spill light from theaccentuated areas is frequentlysufficient to provide adequateambient lighting. Luminaires thatemit a directed, narrow beamcan be used for accent lighting.Adjustable spotlights and direc-tional luminaires are ideal.

general – differentiated

Uniform general lighting usingwide-beamed illumination

Differentiated lighting usingnarrow-beam light fromspotlights




Direct lighting allows diffuse andoriented light, and both generallighting and accent lighting. Alighting plan can be used withdirect lighting that allows differ-

entiated distribution of light.This greatly enhances the three-dimensionality of illuminatedobjects as the result of high con-trasts.With indirect lighting, lighting isdesigned to give diffuse generallighting. Indirect lighting pro-duces a highly uniform, soft lightand creates an open appearancedue to the bright room surfaces.Problems caused by direct andreflected glare are avoided. Indi-rect lighting alone can give a flatand monotonous environment.

direct – indirect

Direct lighting with oriented light

Indirect lighting creates an openspatial impression


Light distribution





Light distribution

The decision for narrow orwide light distribution is closelyconnected with the concept of general or differentiated light-ing. Luminaires with a beam

angle of less than 20° are knownas spotlights and above 20° asfloodlights. With downlights, thecut-off angle also gives an indi-cation of the width of the lightdistribution. Wide light distribu-tion creates a higher proportionof vertical illuminance.

wide – narrow

Wide light distribution forindirect lighting

Narrow-beam light for high-lighting




Symmetrical light distributionis used for providing even light-ing. The light distribution can bewide for downlights used for thegeneral lighting of horizontal sur-

faces. With spotlights, the lightdistribution is narrow beamed toprovide highlighting. Luminaireswith asymmetric light distribu-tion are designed to give uniformlight distribution for surfaceslocated to one side. Typical lumi-naires with this characteristicare wallwashers and ceilingwashlights.For luminaires with axially sym-metrical beam emission, such aslight structures, two light inten-sity distribution curves are given.

symmetrical – asymmetrical

Symmetrical light distribution forgeneral lighting

Asymmetrical light distributionof wallwashers for uniform wallillumination


Light distribution




Focusing on horizontal lightingis frequently in line with thedecision to plan functional, user-orientated light. This applies tothe case of lighting for work-

places for instance, where thelighting design is primarily aimedat giving uniform lighting forhorizontal visual tasks. In suchcases, vertical lighting compo-nents are predominantly pro-duced by the diffuse light thatis reflected by the illuminated,horizontal surfaces.The decision to plan verticallighting may also be related tothe task of fulfilling functionalrequirements when illuminatingvertical visual tasks, e.g. forshelves, blackboards or paint-ings. However, vertical lightingfrequently aims to create a visual

environment. Vertical lighting isintended to emphasise the char-acteristic features and dominantelements in the visual environ-ment. This applies not only to thearchitecture itself, whose struc-tures can be clearly portrayed byilluminating the walls, but also tothe accentuation and modellingof the objects in the space.

horizontal – vertical

Horizontal lighting for workplaces


Light distribution

Vertical lighting accentuates thetexture using facade lighting

In most cases the choice of luminaires will be confined tothe standard products available,because they can be supplied atreasonably short notice, haveclearly defined performance char-acteristics and have been testedfor safety. Standard luminairescan also be used in special con-structions, such as lighting instal-lations that are integrated intothe architecture (e.g. cove light-ing or luminous ceilings). In thecase of large-scale, prestigiousprojects consideration may alsobe given to developing a customdesigned solution or even a newluminaire. This allows the aes-thetic arrangement of luminairesin architecture or in a character-istically designed interior and thesolution of specific lighting tasksto be effected in closer relation tothe project than if only standardproducts are chosen. Additionalcosts for development and timeconsiderations must be includedin the calculation of overall costsfor the project.

Custom design




The colour of light from a lumi-naire depends on the lamp. Therange of white light colours isdivided into warm white, neutralwhite and daylight white.

Coloured light can be producedfrom these lamps by using colourfilters. The use of a coloured lightsource such as an LED or fluores-cent lamp creates coloured lightdirectly and avoids the reducedtransmission of colour filters.With luminaires having RGB tech-nology, red, blue and green pri-mary colour light sources can bemixed to give a multitude of col-ours. An electronic control allowsthe light colour to be changeddynamically.


Luminous colour




There are two basic contrastingconcepts for the arrangementof luminaires in an architecturalspace, which can allocate differ-ent aesthetic functions to the

lighting installation and providea range of lighting possibilities.On the one hand, there is theattempt to integrate the lumi-naires into the architecture asfar as possible, and on the otherhand, the idea of adding theluminaires to the existing archi-tecture as an element in theirown right. These two conceptsshould not be regarded as twocompletely separate ideas, how-ever. They are the two extremesat either end of a scale of designand technical possibilities, whichalso allows mixed concepts andsolutions. The decision to opt for

a stationary or variable lightinginstallation overlaps the decisionto go for an integral or additivesolution; it is determined by thelighting requirements the instal-lation has to meet rather than bydesign criteria.


Methods of mounting

Methods of mounting

In the case of integral lighting,the luminaires are concealedwithin the architecture. The lumi-naires are only visible throughthe pattern of their apertures.Planning focuses on the lightingeffects produced by the lumi-naires. Integral lighting can there-fore be easily applied in a varietyof environments and makes itpossible to co-ordinate luminairesentirely with the design of thespace. Integral lighting generallypresents a comparatively staticsolution. The lighting can only bechanged by using a lighting con-trol system or by applying adjust-able luminaires. Typical luminaireshere are recessed wall or ceilingluminaires.

Integral lighting




In the case of additive lighting,the luminaires appear as elementsin their own right. Besides plan-ning the lighting effects whichare to be produced by these

luminaires, the lighting designeralso has to specify the luminairedesign and plan a lighting layoutin tune with the architecturaldesign. The range extends fromharmonising luminaires withavailable structural systems toselecting luminaires that willhave an active influence on theoverall visual appearance. Whatis gained in flexibility is offsetby the task of harmonising thevisual appearance of the lightinginstallation with its surroundingsand of avoiding the visual unrestthrough the mixing of differentluminaire types or by a confusing

arrangement of light structures.Typical luminaires here are spot-lights and light structures, as wellas pendant luminaires.

Additive lighting


Methods of mounting

With stationary, mounted lumi-naires, different light distribu-tions are available, e.g. adjustableluminaires such as directionalluminaires. The luminaire layoutshould be thoroughly checkedin the design phase becauseany subsequent alterations torecessed luminaires are verycostly.

Stationary lighting




There are different ways of mak-ing a lighting installation flexible.The highest degree of flexibility,as required for lighting temporaryexhibitions and for display light-

ing, is provided by movable spot-lights mounted on track systemsor support structures. These allowthe luminaires to be realigned, oreven rearranged or replaced.

Movable lighting


Methods of mounting



82

A


In the case of adjustable lumi-naires, such as spotlights ordirectional luminaires, glare alsodepends on the light distributionof the luminaire. Glare primarily

occurs if the luminaire is not cor-rectly adjusted.In the case of stationary lumi-naires, such as downlights orlight structures it is necessary todistinguish between the elimina-tion of direct glare and reflectedglare. In the case of direct glare,the quality of glare limitationdepends on the light distributionof the luminaire. The greaterthe cut-off angle in downlights,the greater the visual comfortprovided by the luminaire dueto improved glare control.

Glare


Luminance

Standards exist for the lightingof workplaces, which stipulateminimum cut-off angles or high-est permissible luminances in the

cut-off range. For workstationswith VDTs there are specificrequirements. The critical areacan be defined as that portionof the ceiling which is seen bythe user in a mirror coveringthe working area. In the case of luminaires with mirror reflectorsdirect glare control improves thegreater the cut-off angle. Thestandard cut-off angles are 30°and 40°.The UGR (Unified Glare Rating)process is used to evaluate andlimit the direct discomfort glarein indoor areas. The UGR value isinfluenced by the light source’sluminance, its visible size (solidangle) and its position (positionindex), as well as the luminanceof the background. It is usuallybetween 10 and 30. The smallerthe UGR value, the less the glare.

Standards

By projecting the field of visiononto the ceiling surface it ispossible to define the area inwhich the luminaires may havea negative influence on contrastrendering.

With regard to glare a distinctionis made between direct glare,caused primarily by luminaires(1), reflected glare in the case of horizontal visual tasks (2) andreflected glare in the case of vertical visual tasks, e.g. at VDTworkstations (3).

Glare limitat ion at VDT work sta-tions: for areas with VDT worksta-tions a cut-off angle α of at least30° is recommended.





Illuminance

Recommended illuminance levelE according to CIE for variousactivities

Visual performance generallyimproves sharply as the illumi-nance level is increased. Above1000 lux, however, it increasesmore slowly, and at extremely

high illuminance levels it evenstarts to decrease due to glareeffects.However, following a set of fixedrules for illuminance levels giveslittle consideration to actualperception. It is not the luminousflux falling on a given surface– illuminance – that produces animage in the eye, but the lightthat is emitted, transmitted orreflected by the surfaces. Theimage on the retina is createdentirely by the luminance patternof the perceived objects, in thecombination of light and object.





Safety requirements

Luminaires are required to meetthe safety requirements in allcases; in Germany this is usuallyguaranteed by the presence of atest symbol. In some cases there

are other requirements that haveto be met and the luminairesmarked accordingly. Specialrequirements have to be fulfilledby luminaires that are to be oper-ated in damp or dusty atmos-pheres, or in rooms where there isa danger of explosion. Luminairesare classified according to theirmode of protection and protec-tion class, whereby the protec-tion class indicates the typeof protection provided againstelectric shock, and the mode of protection its degree of protec-tion against contact, dust andmoisture.

Protection mode

Identification of protectionmode (IP):

code X, foreign body protection

Identification of protectionmode (IP):

code Y, water protection

Special requirements to firesafety have to be fulfilled whenluminaires are installed in or onfurniture or other inflammablematerials.

Protection classes

Protection classes for theelectrical safety of luminaires

Identification of specialluminaire properties and safetyrequirements





Luminaire arrangement

Designing the lighting layoutshould not be seen as a solelytechnical or functional process.In quantitative lighting design,it has become preferred practiceto plan the lighting layout of ceiling-mounted luminaires toproduce a completely uniformgrid, with the aim of providinguniformly distributed lighting.Consequently, there is no direct

link between lighting layoutand lighting effect; by exploit-ing the wide range of luminairesavailable it is possible to achievea designed pattern of lightingeffects using a variety of light-ing layouts. The lighting designshould make use of this scope,producing ceiling designs thatcombine functional lighting withan aesthetic lighting layout thatrelates to the architecture.

Floor CeilingWall

Object Linear elementsPoint source patterns



86

A


E GuideDesigning with light | Practical planning | Luminaire arrangement

Floor

The recommended offset fromthe wall (a) is half the luminairespacing (d). The luminaire spac-ing (d) between two adjacentstructures should correspond tothe height (h) above the floor orwork surface.

Floor

Cut-off angle The greater the cut-off angle,the greater the visual comfortprovided by the luminaire due toimproved glare control. The samelighting layout of downlightsproduces different distributionson the wall.A cut-off angle of 40° givesthe best possible compromisebetween the necessary horizon-tal illuminance on the floor and

vertical illuminance. Vertical i lluminance is important

in places such as salesroomswhere products should be wellilluminated. On downlights with a30° cut-off angle, the maximumluminous flux is emitted at a highlateral angle.Due to their narrow light distri-bution, downlights with a 50°cut-off angle achieve very a highvisual comfort for high rooms.

No light is emitted beyond thecut-off angle.

30° cut-off angle

40° cut-off angle 50° cut-off angle





Wall

The distance from the wall forwallwashers should be at leastone third of the room height.Alternatively, the wall offset isgiven by a 20 degree line extend-ing from the base of the wall upto the ceiling. Whereas for normalroom heights the luminaire spac-

ing is the same as the wall offset,in high rooms this spacing mustbe reduced to compensate forthe illuminance which is gener-ally reduced. Wallwashers do not

Wall

Room corner

The recommended distance of downlights to the wall is gener-ally half the distance betweenthe downlights. Corner-mountedluminaires should be mounted onthe 45° line to produce identicalscallops on both walls.

give optimum uniformity until atleast three luminaires are used.A wallwasher in a room cornershould be positioned on the 45°line.

Mirrored walls

For mirrored walls, the lightinglayout should be chosen such that

the pattern continues uniformlyin the reflection.




E

Wall element

In spaces with dominant architec-tural features, the lighting layoutshould harmonise with the archi-tectural elements.

Ceiling

Ceiling lighting requires sufficientroom height to achieve even lightdistribution. Ceiling washlightsshould be mounted above eye-

level to avoid direct glare. Theceiling offset depends on thedegree of evenness required andshould generally be 0.8m.

Object

Objects can be illuminated withlight directed from between 30°to 45° to the vertical. The steeperthe incident light, the more pro-nounced the three-dimensionalityof the illuminated object. If theangle of incidence of the light isapproximately 30°, the so-called“museum angle”, this produces

maximum vertical lighting andavoids reflected glare that maydisturb the observer. In the caseof reflecting surfaces, e.g. oilpaintings or pictures framed

behind glass, attention must bepaid to the angle of incidenceof the light to avoid disturbingreflections that may arise in theobserver’s field of vision. This willalso avoid any heavy shadow, e.g.picture frame shadows on thepicture.

GuideDesigning with light | Practical planning | Luminaire arrangement




E

Horizontal surfaces

High luminance values reflectedby surfaces or objects causesecondary glare. The luminairesshould not be positioned in criti-cal areas. Indirect illuminationwith diffuse light reduces thesecondary glare. The beam shouldbe aimed such that shadows on

the work surface are avoided.

Vertical surfaces

If a reflective surface is arrangedtransversely, luminaires can bemounted in front of the excludedceiling zone. If a reflective surfaceis arranged vertically, they canbe mounted next to the excludedceiling zone.





E

Point source The simplest layout of thesepoints is a regular grid, in a par-allel or staggered arrangement.A regular pattern of identicalluminaires can easily result in a

monotonous ceiling appearance,plus the fact that differentiatedlighting is practically out of thequestion.

Point source combinations An alternating grid of differentindividual luminaires or luminairecombinations can produce moreinteresting arrangements; in thiscase luminaires of the same ordifferent types can then be pur-posefully combined.


Point source patterns

Point sources:regular and staggered layouts

The point sources may beluminaires of different shapesand sizes, or compact groups of luminaires.




Line A further step towards morecomplex design forms is the lineararrangement of point sources. Incontrast to simple lighting lay-outs in grid patterns, the ceiling

design in this case relates moreclosely to the architecture of thespace. The ceiling is designedalong the lines dictated by thearchitectural form of the space.This may involve following exist-ing lines or purposefully arrang-ing the luminaires in contrast tothe existing formal language.

E

Forms Since the linear arrangement of the luminaires does not neces-sarily relate to an actual line suchas the course of a wall, ceilingprojections or joists, the luminairearrangement can only be createdon the basis of the perceptionof gestalt. These laws of gestaltmust receive special attentionduring the planning phase. Thecrucial criteria are the equidis-tance and proximity of luminairesto each other.


Point source patterns

Point sources:linear arrangements

Luminaire arrangements canfollow existing architecturalstructures or create patterns of their own.




Line Whereas linear arrangementsconsisting of a series of points areonly produced indirectly by ourperception of the gestalt, theycan also be directly formed of

linear elements. These linear ele-ments can be particular types of luminaires, or even trunking sys-tems. Light structures and trackarrangements or other trunkingsystems belong to this designcategory.The formal language of lineararrangements is identical to thatof rows of points. As the visualforms produced when linearluminaires are used are real andnot just implied, more complexarrangements can be plannedwith no danger of distortionthrough perception.

Linear and point sources Creative design allows both thealternating application of dif-ferent luminaire forms and theuse of spotlights on lightingstructures or trunking systems.This allows differentiated lightingwithout the individual luminairesdisturbing the intrinsic appear-ance of the structure.


Linear elements




E

Decorative solutions The combination of different ele-ments gives rise to a broad rangeof design possibilities, includingdecorative solutions.

Linear structures The rectangular arrangement of

tracks corresponds to the shapeof the room. This allows flexiblelighting of all wall surfaces andaccentuating of objects in thespace.


Linear elements





Mounting

Both technical and design aspectsare important when mounting.If the arrangement of the lumi-naires is already fixed, then thefocus shifts to the mountingdetail. Various mounting versionsare available for downlights, e.g.surface-mounting, recessed-mounting or pendant suspension.

FloorCeiling Wall




Suspended ceilings In the case of flat suspended ceil-ings, e.g. plasterboard ceilings,the luminaires can almost alwaysbe arranged irrespective of thesuspended ceiling grid. The lumi-

naires are fixed firmly in the ceil-ing apertures provided; if neces-sary, the weight of the luminairemust be carried by additionalsuspensions fixed onto or inclose proximity to the luminaire.If the ceiling is to be plastered,plaster rings are required for theluminaire apertures.

E GuideDesigning with light | Practical planning | Mounting

Ceiling

Panel ceilings For open grid ceilings and

honeycomb-grid ceilings thereare recessed cassettes availablecomplete with suitable aperturesfor the recessed mounting of downlights. The cassettes aredimensioned to suit the respec-tive ceiling grids. They can replacea ceiling panel or allow the instal-lation of luminaires between ceil-ing panels which would otherwisenot be suitable to take the staticload.

Ceiling channel Light sources can be mounted ina track ceiling channel in order tointegrate them invisibly into theceiling.




Pendant luminaires Pendant mounting can beeffected in a variety of ways.Light-weight luminaires are usu-ally suspended by the connectingcable. Heavier luminaires require

a separate suspension device. Thismay take the form of a strandedwire cable or a pendant tube,which generally contains theconnecting cable.

E GuideDesigning with light | Practical planning | Mounting

Ceiling

Concrete ceilings For recessed mounting into con-

crete ceilings the luminaire aper-tures are created when the ceilingis cast. Another possibility is toinstall prefabricated housings,which are also attached onto theconcrete shuttering and remain inthe ceiling. It is essential to checkthat the planned lighting layoutis compatible with the structureof the ceiling, whether specificinstallation locations must beavoided, for example, due to con-cealed joists or whether the rein-forcement of the ceiling shouldbe co-ordinated with the lightinglayout.




Wall Luminaires can be mounted ontowall surfaces or recessed intothe wall. The latter can be ineither concrete or hollow walls.Luminaires can be mounted on

wall brackets or cantilever armsfor indoor partitions or outdoorfacades.

E Guide

Designing with light | Practical planning | Mounting

Floor Luminaires for floor or ground

installation can be surface-mounted or recessed-mounted.When recess-mounted in thefloor or ground, the luminairecover must be robust and provideprotection against the ingress of moisture. Bollard luminaires andmast luminaires may also be usedoutdoors.





Maintenance

By stipulating a light loss factorwhen planning the lighting, theintervals at which maintenance isto be carried out can be control-led. By keeping light loss factors

low, the lighting level will initiallybe higher and the period duringwhich luminous flux is graduallyreduced to below the criticalvalue will be extended. Usinga suitable maintenance factor,lamp replacement and the clean-ing of luminaires can be timedto take place simultaneously. Theadjustment of luminaires is alsoclassified as maintenance in theinterest of the qualitative aspectsof the lighting installation. Inthe area of display lighting inparticular, luminaires have to berealigned to accommodate thelayout of a new arrangement.

A maintenance plan shouldenable the operator to service theinstallation at regular intervals,checking whether the technicalrequirements are being met andthe lighting is performing asplanned.





Visualising light

Representing lighting installa-tions and their lighting effectsin architecture plays a key role inlighting design. The range of rep-resentations includes the wholegamut from technically orientedceiling plans to graphic illustra-tions of varying complexity tocomputer-calculated room repre-sentations and three-dimensionalmodels of architecture or light-

ing installations. Skilled lightingdesigners use ceiling plans anddiagrams to derive a realistic ideaof the lighting effects achieved.Others in the planning processwith less expertise have to relyon visual representations andtechnical specifications.

Drawing ModelSimulation




E GuideDesigning with light | Visualising light

Drawing

The graphic methods employedextend from simple sketches todetailed and elaborate processes.The more elaborate the methodused, the more accurate is therepresentation of the illuminatedenvironment and the lightingeffects. Perspective room repre-sentations include the positioningof the lighting equipment in theroom.

Sketch Mood boardStory board

Technical drawing Diagram




E GuideDesigning with light | Visualising light | Drawing

Sketch

In the simplest case, lightingeffects can be shown in a graphicformat by light beams designedeither as contours, as colouredsurfaces or in grey tones contrast-

ing with the background. Draw-ings that show light beams usinglight, coloured pencils or chalkon a dark background achieve anintense luminosity and are par-ticularly useful for representingoutdoor lighting at night. Whenvisualising an overall concept, adeliberately simplified sketch candemonstrate the lighting effectsproduced more effectively than anallegedly realistic representationwith artificially scaled brightnessratios.




Facade Entrance

Foyer Reception

Room, variant 1 Room, variant 2

Room, variant 3 Detail

Using rough sketches for visuali-sation, the story board acts as acreative script detailing the spa-tial and temporal progression of the lighting effects. It is an effec-

tive tool in scenographic lightingdesign to look at the dynamicprocesses in the building. Theseprocesses result from aspectssuch as the spatial progressionencountered as you walk throughthe building, but also from thetime dimension experienced in aroom throughout the course of a day.


Story board





Mood board

The mood board is a collectionof pictures, sketches, materials,colours, and terms to describeemotions. Where different moodsare required as special effects

in a room, parallel collages withdiverse themes can be used tounderline the statements on con-trasts and colours for the differ-ent light scenes. While the moodboard initially focuses on a broadcollection of pictures, the processof evaluation and concentrationis more analytical.

Mood board with warm, direc-tional light

Mood board with diffuse, coollight




Technical drawing Technical drawings provide exactinformation on the type andpositioning of the luminairesused in the ceiling plan and thesectional drawing. For spotlights,

for example, the drawing canalso specify the alignment of theluminaires. For a better overview,a table can be used to list all theluminaires with their symbols andfeatures. The electrical designersalso require details on circuits,switches, push-buttons and pro-tection modes.


Diagram Diagrams can be used to docu-ment aspects such as the illumi-nance or luminance distributionin a room. In the Isolux diagrams,contours indicate the same illu-minances, while the contours inIso-candela diagrams specify theluminances.




While the spatial representationsof simulation programs reproducethe illuminance levels in a roomby way of diagrams, they alsoprovide a visual impression of thelighting concept. In contrast tothe drawing, the computer graphicfurnishes objective information, asit is based on precise calculations.


Simulation

Qualitative simu-lation

AnimationQuantitative simu-lation




E GuideDesigning with light | Visualising light | Simulation

Qualitative simulation The light simulation for qualita-tive representations focuseson portraying atmosphere. Thespatial perspective provides anaccurate impression useful for

the presentation of the lightingdesign. The degree of detailingcan include photorealistic illus-trations.

Quantitative simulation The quantitative simulation is

used for the analysis of a lightingdesign. It determines the physi-cally correct numerical values forspecific visual tasks. The simula-tion also helps to check compli-ance with requirements specifiedin standards, such as uniformityof illuminance. A further effec-tive visualisation method is falsecolour diagrams which allowlevels to be represented througha colour scale.

Animation Animation combines individualimages generated through simu-lation to produce a film. It is idealto demonstrate dynamic lightingeffects. Animations where eitherthe camera angle remains thesame but the lighting changes orthe lighting stays the same butthe camera is moved are compara-tively simple. Animations whereboth the lighting and the cameraposition change are far more com-plex since each individual image of the film has to be recalculated. Thealternative is to use special videopost-editing processes.




One of the significant advantagesresulting from the use of modelsis that light is not just representedbut becomes effective. Lightingeffects are visualised in all theircomplexity, not merely schema-tised. A further advantage of models is the aspect of interac-tion in that the observer canaccurately check every angle. Adistinction has to be made here

between a working model and apresentation model.


Model

Model making Daylight simulationMock-up




E GuideDesigning with light | Visualising light | Model

Model making Size and accuracy limit the infor-mative value of the simulationand should be determined accor-dingly. The scale ranges from 1:100or 1:200 for the daylight effect of

whole buildings to scales of 1:20to 1:10 for differentiated lightingeffects in individual areas.The most critical factor, specifi-cally when using very small-scalemodels, is usually the size of theluminaires themselves. Variationsin the light intensity distributionare clearly reflected in the result.The accuracy of luminaire repro-ductions is limited on account of the dimensions of the light sourcesavailable. The result is that design-ers often use light guide systemsfrom an external light source tosimulate the output from severalluminaires.

Mock-up A mock-up is a reproduction of aroom situation at a scale of 1:1.A mock-up of the luminaire orthe architectural space concerned

is ideal as a basis for decisionsspecifically when assessing cus-tomised luminaires or luminaireswhich are to be integrated intothe architecture. To limit the effortinvolved, a mock-up is based on anarchitectural section for maximumbenefit.




Daylight simulation In the simplest case, both thesun and the daylight can be useddirectly in outdoor scenes or elsebe reproduced exactly using asolar simulator or an artificial

sky. When simulating sunlightoutdoors, a sundial-type displayinstrument is used to position themodel at precisely the angle of incidence of the light that cor-responds to a specific season andtime of day. In the solar simulator,this is performed by a movable,artificial sun. Both methods allowreliable studies of the lightingeffects in and around a buildingand of engineering designs fordaylight control or sun protec-tion even for small-scale models.Cameras are used to capture theseobservations and to document thelighting changes throughout the

day or year.The artificial sky is used to simu-late the lighting conditions on acloudy day and to take measure-ments of the daylight ratio.

E GuideDesigning with light | Visualising light | Model




Types of lighting Luminaire groups Lighting applications

GuideIndoor lighting

E

Light determines the mood of a room. Lighting applicationsand the corresponding lightingeffects of different luminaires arerehearsed using simulations andarchitectural examples.





Types of lighting

E

The effect of rooms, areas andobjects greatly depends on thetype of lighting. This ranges fromuniform washlighting through tohighlighting and the projectionof gobo images.

General Washlighting Accentuation

Projection Orientation




E GuideIndoor lighting | Types of lighting

General

direct, aimed direct, diffuse indirect

General lighting refers to an evenillumination, usually related to ahorizontal working plane. Quanti-tative aspects are often a primaryconsideration at the work place orin pedestrian traffic zones. Directlighting permits both diffuse anddirected light. Indirect lighting,on the other hand, produces avery even, soft light.

direct and indirect




A direct and aimed general light-ing produces an even illuminationon the horizontal working plane.The architecture is visible and it ispossible to orientate oneself and

work in the room.

The directed light produces good

modelling and brilliance. Theuniformity on the working planeincreases as the room heightincreases or as the beam anglewidens. Directed light enablesgood appreciation of form andsurface texture. The visual com-fort increases as the cut-off angleincreases. A feature of direct illu-mination is its highly efficientuse of energy. At the work place,secondary glare must be takeninto consideration.

Observation

Conclusion

E GuideIndoor lighting | Types of lighting | General

direct, aimed

Applications

Projects:Dubai International AirportCentre Pompidou, ParisCongress Palace, ValenciaERCO, Lüdenscheid




A direct, diffuse general lightingdesignates an even illuminationwith respect to a horizontal work-ing plane. The architecture is vis-ible and it is possible to orientate

oneself and work in the room.

Observation


direct, diffuse

Light structures

Downlights, diffuse

Wall-mounted downlights,diffuse




Direct diffuse light produces

a soft illumination with littleshadow and reflection. The lim-ited formation of shadow resultsin weak modelling capabilities.Shapes and surface textures areonly slightly emphasised. Onefeature of using fluorescentlamps for general lighting isan efficient use of energy.

Conclusion


direct, diffuse

Luminous ceiling

Applications

Projects:Congress Centre, ValenciaPrada, MilanGerman Architectural Museum,FrankfurtFondation Beyeler, Basel

Direct, diffuse general lighting for- working areas- multifunctional rooms- museums

- exhibitions- pedestrian traffic areas

Preferred luminaire groups:- light structures- downlights- wall-mounted downlights- luminous ceilings




An indirect general lighting uses aceiling, wall or other surface as asecondary reflector. The brighten-ing of these surfaces that deline-ate the room or area gives an

open spatial impression.

Observation


indirect

Light structures

Uplights

The diffuse light produces limitedshadows and a weak modelling.Using indirect illumination alonegives a lower spatial differentia-tion. Compared to direct illumi-nation, a considerably higherluminous flux is necessary forachieving the same illuminanceon the working plane. The sec-ondary reflector should boasta high reflectance. Direct andsecondary glare are extensivelyavoided.

Conclusion





indirect

Applications

Projects:

British Museum, LondonEzeiza Airport, Buenos AiresEremitage, St. Petersburg Villa, Salzburg

The prerequisite for an even dis-tribution of light is a sufficientlyhigh room. Indirect illuminationshould be mounted above eye-level. The distance from the ceil-

ing depends on the level of even-ness required and shouldbe at least 0.8m.

Indirect general lighting for:- working areas- multifunctional rooms- pedestrian traffic areas

Preferred luminaire groups- light structures- uplights




Direct/indirect general lightingrefers to a combination of directand indirect illumination withrespect to the horizontal workingplane. The ceiling or walls serve

here as reflection surfaces. Thebrightening of these surfaces thatdelineate the room or area givesan open spatial impression.

Observation


direct and indirect

Light structures

Pendant downlights

The uniformity on the workingplane increases as the roomheight increases. Directed lightenables a good appreciation of form and surface texture. Thesecondary reflector should boasta high reflectance. The uniformityon the ceiling increases the fur-ther away the luminaire is fromthe ceiling. A feature of generallighting with fluorescent lamps isits highly efficient use of energy.

Conclusion




Applications

Projects:

Civic Cleaning Adult-EducationCentre, BerlinReichstag, BerlinPalacio de la Aljaferia, ZaragozaFibanc, Barcelona

Direct/indirect general lightingfor- working areas- multifunctional rooms- pedestrian traffic areas

Preferred luminaire groups:- light structures- pendant downlights


direct and indirect





Washlighting

symmetrical asymmetrical

Washlighting illumination refersto an architecture-related andobject-orientated illumination.The primary purpose is to makevisible the room proportions androom limits. Symmetrical flood-lights are used for washlightingof horizontal surfaces or forgeneral lighting in the area of presentation. A feature of asym-metrical floodlights is the uni-

form light intensity distributionon surfaces.




Symmetrical washlighting pro-duces an even illumination onobjects or surfaces. Washlightillumination is characterised byhigh uniformity and a soft gradi-

ent of light intensity distribution.The illuminated areas of the roomare emphasised by washlighting.

Observation


modelling abilities and enablesgood appreciation of form andsurface structure. Washlightingillumination can serve as a back-ground for accent lighting.

Conclusion

E GuideIndoor lighting | Types of lighting | Washlighting

symmetrical

Applications

Projects:Catedral de Santa Ana, Las PalmasPasseig de Gràcia, BarcelonaRoyal Armouries Museum, LeedsMuseo ‚Fournier‘ del Naipe, Vitor ia

Mounting floodlights on tracksallows a flexible positioning of the luminaires.

Washlighting illumination for:- exhibitions- museums- sales and presentation areas- multifunctional roomsPreferred luminaire groups- floodlights




Asymmetrical washlighting illu-mination is used for illuminatingsurfaces evenly. Wallwashing isa highly valued tool in architec-tural lighting. Vertical illumina-

tion emphasises the walls – orother room limits – in terms of their physical makeup. Brighten-ing the wall surfaces makes theroom look bigger.

Observation


asymmetrical

Wallwasher spotlight

Washlights

Wallwasher




Perimeter luminaire

Uplights

Floor washlights


asymmetrical





asymmetrical

Point-form luminaires lend thewall surface a higher brilliance,whereas with linear luminairesa higher uniformity is achieved.With asymmetrical washlighting,

areas of a room can be definedand thus have attention attractedto them. It can also serve as abackground for accent lightingor form the ambient brightnessfor the work place. To obtain auniform light intensity distribu-tion the correct positioning of

Conclusion

Applications

Projects:British Museum, LondonReichstag, BerlinPalacio de la Aljaferia, Saragoza

Modern art museum, Frankfurt

Washlighting for- exhibitions- museums- sales and presentation areas- multifunctional rooms

Preferred luminaire groups- wallwasher spotlights

- washlightswallwashers- uplights- perimeter luminaires

the luminaires is of great impor-tance.





Accentuation

Highlighting emphasises indi-vidual objects or architecturalelements. This makes it possibleto establish a hierarchy of hownoticeable each item is and to

attract attention.

Observation

Spotlights

Contour spotlights

Directional luminaires





Accentuation

Task light

Accent lighting enables good

appreciation of form and sur-face structure. The focused lightproduces pronounced shadowsand good modelling ability, aswell as brilliance. A narrow beamand a high brightness contrast tothe surroundings give the objectparticular emphasis.

Conclusion

Applications

Projects:Neue Wache, BerlinIglesia del Sagrado Corazón,BilbaoIssey Miyake, ParisPinacoteca Vaticana, Rome

Accent lighting creates pointsof interest and improves thelocal visual performance, e.g. atthe work place. Structures and

textures of objects are clearlyemphasised by the directed light.

Accent lighting for:- exhibitions- museums- sales and presentation areas- restaurants, cafés, wine bars- working areas

Preferred luminaire groups:- spotlightscontour spotlights- directional downlightsdirectional recessed floorluminaires- task lights





Projection

Projectors are used for project -ing signs, patterns and images.This enables an additional levelof information and awarenessto be built up.

Observation

Interesting effects can be created

using gobos and filters.

Conclusion

Applications

Projects:Aragon Pavillon, SevillaHannover MesseTeattri Ravintola, FinlandERCO, Lüdenscheid

Projection Application- exhibitions- museums- sales and presentation areas

- restaurants, cafés, wine bars- hotels

Projections can be made with- spotlight projectors





Orientation

Orientation lighting is definedfirst and foremost by the task of providing orientation. This can beachieved by luminaires that func-tion as sources of illumination or

as signals. Illuminating the roomis of secondary importance here;instead, a row of these luminairesis typically arranged to form anorientation line.

Observation

Floor washlights

Wall-mounted downlights

Recessed floor luminaires




Low illumination levels are suf-

ficient for orientation purposes.Small luminaires with high lumi-nance clearly set themselvesapart form their surroundings.Orientation lighting improvesorientation in complex buildingsand makes it easier to find fireexits in emergencies.

Conclusion

Applications

Projects:Light and Building, FrankfurtPalazzo della Ragione, BergamoHilton Hotel DubaiHilton Hotel Dubai

Orientation lighting for theidentification of - architectural lines- steps and exclusion zones

- entrances- routes- emergency exit routes

Preferred luminaire group- floor washlight- wall-mounted downlights- recessed floor luminaires- orientation luminaires

Orientation luminaires


Orientation





Luminaire groups

E

Luminaires are available in awide variety of types, eachintended to fulfil different light-ing requirements. The same lightdistributions can be achieved withdifferent luminaires. The choicedepends on whether the lumi-naires are to be a design featurein their own right, or whetheran integrative design approachis being followed. Compared to

luminaires that are permanentlymounted, track-mounted lumi-naires offer a higher degree of flexibility.

Track Spotlights Floodlights

Wallwasher Light structures Downlights

Task lights Wall-mountedluminaires

Perimeter luminaires

Recessed floorluminaires

Orientationluminaires

Directive luminaires




Tracks form the basis for a vari-able and flexible lighting designthat can orientate itself aroundthe changing interior design andusage of a room. Mating adapters

on the luminaires perform boththe electrical and mechanicalconnection.

Tracks provide a flexible form

of voltage supply for spotlights,floodlights and wallwashers, foraccent lighting and washlightingof all professional lighting situ-ations. Using multiphase tracksmakes it possible to operate dif-ferent circuits simultaneously.Recessed tracks are inconspic-uous architectural details. Thetracks can also be suspendedvia pendant tubes or wire rope.They should correspond to thearchitecture in their arrangementand form.

Light

E GuideIndoor lighting | Luminaire groups

Track

Applications

Projects:Teattri Ravintola, HelsinkiChristie's Showroom, New YorkCaras Gourmet Coffee Kranzler-eck, BerlinKayser private home, Neuenrade





Spotlights

The mounting location and theorientation are variable. Spot-lights are offered with differentbeam emission angles and lightdistributions.

Criteria for spotlights- choice of lamp determines lightcolour, brilliance, functional life,light intensity- emission angle determines thebeam of light and is defined bythe reflector- cut-off angle limits glare andincreases visual comfort- rotatable and tiltable- accessories:lenses, filters; glare control

Light

SpotlightsSpotlights have a narrow-beam(spot approx. 10°) to wide-beam(flood approx. 30°) light distribu-tion with a rotationally symmetri-cal beam.

The use of accessories is alsotypical for spotlights:- lenses:spread or sculpture lenses

- filters:- filters: colour filters, ultravioletor infrared filters- barn doors, dazzle cylinders,multigroove baffles or honey-comb anti-dazzle screens

Contour spotlightsContour spotlights with lensesfor projection for various beamemission angles.Some types of spotlight areequipped with convex lenses orFresnel lenses for a variable beamangle. In addition, spotlights withimage contouring or project-ing systems (contour spotlights)enable different beam contoursor projected images by project-ing through apertures or stencils(gobos).




Applications

Projects:Christie´s Auctioneers, New YorkGmurzynska Gallery, CologneBunkamura Museum of Art, TokyoExpo Seville, Spain

For highlighting or projection in:- museums- exhibitions, art galleries- sales rooms- presentation and display areas

Since they enable variable mount-ing locations and orientation,spotlights can be adapted to suitchanging tasks. A narrow lightdistribution enables smaller areas

to be illuminated, even from alarger distance. Conversely, thewide light distribution of projec-tor floodlights enables a largerarea to be illuminated with a sin-gle luminaire. Gobos and struc-tured lenses are used to projectlighting effects. In addition, filterfoils can also be used.


Spotlights

On pictures on walls or objects ina room, the light should be inci-dent at an angle of less than 30°.

Arrangement





Floodlights

LightFlooldights feature a wide-beamcharacteristic. They are offeredwith a predominantly symmetri-cal light distribution.

Criteria for floodlights- choice of lamp determines lightcolour, brilliance, functional life,efficiency, light intensity- uniformity: optimised reflectorfor even illumination of areas- gradient: soft edge to the beamof light- light output ratio is increased byoptimised reflector technology

Applications

Projects:Catedral de Santa Ana, Las PalmasPasseig de Gràcia, BarcelonaRoyal Armouries Museum, LeedsMuseo ‚Fournier‘ del Naipe, Vitor ia

Floodlights provide even illumi-

nation of areas or objects for:- museums- exhibitions- trade-fair stands- sales areas- presentational areas

The luminaires should corre-spond to the architecture intheir arrangement and form.





Wallwasher

Wallwashers have a wide-beamcharacteristic. They are offeredwith an asymmetric light distri-bution.

Criteria for wallwashers- choice of lamp determines lightcolour, brilliance, functional life,light intensity- uniformity: optimised reflectorfor even illumination of areas- gradient: soft edges to the beamlight output ratio is increased byoptimised reflector technology

Light

Wallwashers (spotlights)

Wallwashers have an asymmet-ric light distribution for evenlyilluminating wall faces. Track-mounted wallwashers allow theluminaire spacing to be flexiblyadjusted as required.

Wallwashers, tiltable(spotlight)Spotlights with wallwasher attach-ment feature a asymmetric light

distribution for evenly illuminat-ing wall surfaces. Track-mountedwallwashers allow the luminairespacing to be flexibly adjustedas required. Wallwashers withkick-reflector have an asymmetriclight distribution for evenly illu-minating wall faces.

WashlightsWallwashers have an asymmetriclight distribution for evenly illu-minating wall faces. In addition,they also feature a downlightcomponent for evenly illuminat-ing the floor.




Double-focus wallwashersDouble-focus wallwashers havean asymmetric light distributionfor evenly illuminating wall faces.The shielding of the lamp provides

high visual comfort and preventsthe emission of spill light. Thehomogeneity of the wallwashingis particularly high.


Wallwasher

Lens wallwashersLens wallwashers have an asym-metric light distribution forevenly illuminating wall faces.The lens serves to spread outthe beam.

WallwashersWallwashers have an asymmetriclight distribution for illuminatingwall faces.

Perimeter luminairesPerimeter luminaires with reflec-tors have an asymmetric light dis-tribution for illuminating verticalsurfaces. As a linear light source,they produce an even illumina-tion of wall surfaces.




Applications

Projects:British Museum, LondonCrescent House, WiltshireMediathek, SendaiWeimar College of Music

Wallwashing is an importantcomponent of architectural light-ing for adding emphasis to roomareas and for illuminating higher,vertical faces or wall areas for:- museums- exhibitions- trade-fair stands- auditoriums- halls in public buildings andshopping malls

- sales areas- presentational areas

Surface-mounted luminaires actas a feature in the room. Theyshould correspond to the archi-tecture in their arrangement andform.

The offset from the wall forwallwashers should not be lessthan one third of the wall height.This corresponds to an angle of at least 20°. The optimal ratio of

wall offset to luminaire spacingfor avoiding evenly illuminationis 1:1. Independent of the actualroom height and offset from thewall, tiltable luminaires must bealigned on the lower part of thewall.

Arrangement


Wallwasher




Light structures are luminairesthat additionally allow the pos-sibility for attaching mobileluminaires, often using integratedtracks or singlets. Light structures

consist of a tubular or panel ele-ments and are usually suspendedfrom the ceiling. First and fore-most, light structures use ele-ments with integrated luminairesfor linear light sources that canbe used both for direct generallighting and for indirect lightingwith light reflected by the ceil-ing. Elements with integrateddownlights or directional lumi-naires provide accent lighting.

Light

Luminaires

DirectLight structures with direct lighthave an axially symmetric lightdistribution emitted downwardsfor illuminating the usable sur-faces.

LuminairesIndirectLight structures with indirectlight distribution have an axially

symmetric light distribution emit-ted upwards for illuminating theceiling.

LuminairesDirect/IndirectLight structures with direct/indi-rect light distribution have anaxially symmetric light distribu-tion emitted upwards and down-wards for illuminating the usablesurfaces and the ceiling.

LuminairesWallwashingLight structures for wallwashinghave an asymmetric light distri-bution for evenly illuminatingwall faces.


Light structures




Applications

Projects:Reichstag, BerlinXaverian Brothers High School,Westwood MARegional Govt., BerlinShanghai Museum

General lighting in- offices, medical practices- pedestrian traffic areas- additional accent lightingand washlighting with the helpof spotlights, floodlights andwallwashers

The offset from the wall (a) isrecommended as being half the luminaire spacing (d). Theluminaire spacing (d) betweentwo neighbouring structures

should correspond to the height(h) above the floor or work sur-face. The distance to the ceilingdepends on the level of evennessrequired on the ceiling. The dis-tance to the ceiling should meas-ure at least 0.8 m for indirectlighting so that an even illumi-nation is ensured.

Arrangement


Light structures





Downlights

Downlights emit a beam that isdirected downwards at either aperfectly vertical or an adjust-able angle. They are offeredwith narrow-beam, wide-beam,

symmetrical or asymmetric lightdistribution.

Criteria for downlights- choice of lamp determines lightcolour, functional life, efficiency,light intensity- emission angle determines thebeam of light and is defined bythe reflector- cut-off angle limits glare andincreases visual comfort- light output ratio is increased byoptimised reflector technology

Light

Double-focus downlights

Double-focus downlights have arotationally symmetric beam thatis directed vertically downwards.On double-focus downlights, aspecial reflector shape enablesa high luminous flux even forsmaller ceiling apertures.

DownlightsDownlights have a rotationallysymmetric beam that is directedvertically downwards.

WashlightsWashlights have an asymmetricbeam that is directed verticallydownwards and onto verticalsurfaces. They provide an evenillumination for wall and floorsurfaces. Special forms are doublewashlights for illuminating twoopposite wall sections and cornerwashlights for illuminating cor-ners of rooms.

The cut-off angle of narrow-beamdownlights makes them a highlyfree of glare. On downlights withDarklight reflector, the lamp'scut-off angle is identical to that

of the luminaire. This gives aluminaire with the widest beampossible while simultaneouslyhaving an optimised light outputratio. The use of a diffuser reduc-es the luminance in the luminaireand thereby improves the visualcomfort.





Downlights

Lens wallwashers

Lens wallwashers have an asym-metric light distribution, whichis aimed at vertical surfaces.They are used for illuminatingwall surfaces evenly. On lenswallwashers special lens reflec-tion systems ensure even wallillumination. The light is spreadout by lenses and directed ontothe wall by wallwasher reflectors.The Darklight reflectors of thelens wallwashers are visible frombelow and are glare-free.

WallwashersWallwashers have an asymmetriclight distribution, which is aimedat vertical surfaces. They are usedfor illuminating wall surfacesevenly.

Directional downlightsDirectional downlights are usedfor highlighting individual areas orobjects with a medium to narrowlight distribution. They combinethe advantages of a downlightwith the flexibility of directionalspotlights. Above the rotationalsymmetric darklight reflectors, thereflector lamps emit their beam of light perpendicularly downwards,yet they can be rotated by 360°and tilted up to 20°. Because theDarklight reflector ensures thata cone of light is formed fromdirectional luminaires, the cut-off

angle is consistent on all direc-tions.

Double-focus wallwashersDouble-focus washlights have anasymmetric light distribution thatis directed at vertical surfaces.They are used for illuminating

wall surfaces evenly. Double-focus wallwashers are fitted withspecial, internal wallwasher seg-ments. With this special kind of reflector technology the lamp ishidden from the direct view of the observer at all times.





Downlights

The offset from wall should

measure approximately half of the luminaire spacing in order toachieve sufficient brightness onthe wall and well proportionedscallops of light. To attain an evenillumination on a reference plane,the luminaire spacing should notexceed the mounting height hby more than 1.5:1. An optimalevenness is achieved when d = h.To obtain symmetrical scallops ina corner, one downlight must bepositioned on the 45° diagonal.

Arrangement

Downlights

The offset from the wall shouldmeasure at least one third of theroom height. Alternatively, theoffset from the wall is where a20 degree line projected upwardsfrom the base of the wall inter-sects the ceiling. An optimumevenness is obtained when theluminaire spacing is the same asthe offset from the wall, or atleast does not exceed it by morethan 1.5 times. Wallwashers onlydevelop their optimal evennessas of a minimum number of threeluminaires. The position of awallwasher in a corner of a roomshould lie on the 45° line.

ArrangementWallwashers

Directional luminairesDirectional downlights are usedfor highlighting individual areasor objects with a medium to nar-row light distribution.




Applications

Projects:

Maritime Museum OsakaBritish Museum, LondonCentre Pompidou, ParisArmand Basi Shop, Barcelona

Downlights are a universal instru-ment for functional, architectonicand accentuating lighting.

Recessed downlights are incon-

spicuous architectural details,whereas surface-mounted down-lights and pendant downlightsact as features in the room. Theyshould correspond to the archi-tecture in their arrangement andform.


Downlights





Task lights

Task lights emit their light down-wards onto a work surface. Theyare offered with narrow-beam orwide-beam light distribution.

Criteria for task lights- The choice of lamp determineslight colour, functional life, effi-ciency and light intensity- Gradient: soft edges to thebeam of light- glare-free light- rotatable and tiltable

Light

Applications

Projects:Architectural office, StockholmKhalil Al-Sayegh, DubaiSuccess advertising agencyNordwalde; Regional Govt., Berlin

Task lights are designed forindividual lighting for the work-station.





Wall-mounted luminaires

Wall-mounted downlights aredefined first and foremost bytheir type of mounting and notby their light characteristics.Different light distributions are

possible such as narrow-beamed,wide-beamed, symmetrical orasymmetrical in various direc-tions.

Criteria for wall-mounteddownlights- choice of lamp determines lightcolour, functional life, efficiency,light intensity- emission angle determines thebeam of light and is defined bythe reflector- cut-off angle limits glare andincreases visual comfort- light output ratio is increased byoptimised reflector technology

Light

Ceiling washlightsCeiling washlights have an asym-metric light distribution and emitlight upwards onto horizontalsurfaces. The ceiling surface isilluminated evenly and over alarge area. On ceiling washlights,the section of the ceiling to beilluminated can be partly clippedalong the luminaire's main axiswith the help of infinitely adjust-

able cut-off shields. Uplightsdifferentiate themselves fromceiling washlights by their differ-ent reflector geometry, alteredlight distribution, and higher lightoutput ratio.

Floor washlightsFloor washlights have an asym-metric light distribution and emitlight downwards onto horizontalsurfaces.





Wall-mounted luminaires

Applications

Projects:Citibank, ParisMuseo de Historia, BarcelonaHilton Hotel Dubai CreekLight and Building, Frankfurt

For illumination of ceilings orfloors in:- churches- theatres- museums- pedestrian traffic areas

Recessed wall-mounted down-lights are inconspicuous archi-tectural details, whereas surface-mounted downlights act as a

feature in the room They shouldcorrespond to the architecture intheir arrangement and form.

Ceiling washlights should bemounted above eye-level. Thedistance to the ceiling dependson the level of evenness requiredon the ceiling. The distance to the

ceiling should measure at least0.8 m for indirect lighting so thatan even illumination is ensured.

ArrangementCeiling washlights

The mounting height (h) of floorwashlights near to seats or seat-ing should be less than eye-level(1.2 m), normally 0.8 m above thefloor level.

ArrangementFloor washlights





Perimeter luminaires

Perimeter luminaires are linearluminaires with a wide-beamedcharacteristic for evenly illumi-nating vertical surfaces. Perimeterlighting refers to a lighting con-

cept whereby fluorescent lampsare sunk directly into a joint tothe wall. These luminaires areavailable with or without reflec-tor. A higher, even quality of lighting is obtained however byluminaires with reflectors and seta distance from the wall. The low

Light

Perimeter luminairesPerimeter luminaires with reflec-tors have an asymmetric light dis-tribution for illuminating verticalsurfaces. As linear light sourcesthey provide an even illuminationof wall faces.

Linear grazing lightPerimeter luminaires for grazinglight are positioned directly onthe wall. The illuminance on thewall decreases greatly as the dis-tance from the lamp increases.

luminance and linear format of fluorescent lamps result in a lowbriliance.

Criteria for perimeter luminaires

- uniformity: optimised reflectorfor even illumination of areas

Applications

Projects:Reichstag, BerlinThe Tricycle, LondonPacific Rim Restaurant, HongKongPolygon Bar and Grill, London

For illuminating vertical surfacesin:- museums- exhibitions- presentational areas

Perimeter lighting out of haunches emphasises archi-tectonic features. Due to therecessed ceiling mounting,perimeter luminaires are gener-ally inconspicuous architecturaldetails. Luminaires with a sur-face-mounted section and reflec-tor that protrude down from theceiling give a transitionless, uni-form wall illumination from theceiling to the floor.






Recessed floor luminaires emittheir beam upwards. They areoffered with narrow-beamed,wide-beamed, symmetrical orasymmetrical light distribution.

Criteria for recessed floor lumi-naires:- choice of lamp determines lightcolour, service life, efficiency andlight intensity- uniformity: optimised reflectorfor even illumination of areas- range of tilt for directionalluminaires with high glare pro-tection- light output ratio is increased byoptimised reflector technology

Light

Uplights

Uplights feature an upwardsdirected beam with symmetricallight distribution. The narrow,rotationally symmetrical beamsare used for highlighting objects.

Directional luminairesDirectional luminaires are usedfor highlighting individual areasor objects with a medium to nar-

row light distribution. The beamcan be tilted.

Uplight, diffuseRecessed floor luminaires withdiffuse light intensity distributionare used for marking paths oremphasising architectural lines.






Applications

Projects:

Deutsche Bank, TokyoBurj Al Arab, DubaiBurj Al Arab, DubaiMaritim Museum, Osaka

Accent lighting or floodlightingfor- theatres- presentational areas- sales areas

- reception and entrance areas- architectural features

Recessed floor luminaires areinconspicuous architecturaldetails. They should correspond tothe architecture in their arrange-ment and form.






The defining feature of orienta-tion luminaires is that they aredesigned first and foremost toprovide orientation. Such lumi-naires may also function as sourc-

es of illumination or as signals.

Criteria for orientation luminaires- luminance: noticeability of theluminaires in their surroundings

Light

Orientation luminaires, localOrientation luminaires withpoint-form front lens act as alocal orientation light.

Floor washlightsFloor washlights form points of light on the wall and serves asan orientation light on the floorsurface.

Applications

Projects:Sevens department store,Düsseldorf Hilton Hotel, DubaiInstituto Frances, BarcelonaHilton Hotel, Dubai

For identifying:- architectural lines- steps or restricted areas- entrances- routes- emergency exit routes





Directive luminaires

Directive luminaires provideinformation or give directions byway of pictograms or texts. Emer-gency lighting refers to lumi-naires that indicate the escape

route to improve orientation inemergency situations.

Criteria for emergency lightingand directive luminaires- luminance: noticeability of theluminaire in its surroundings- form and colour: to comply withthe standards- luminaire position: to describecorrectly the escape route- emergency power supply- effectiveness: to continuelighting signs upon mains powerfailure

Light

Luminaires

Emergency lighting and directiveluminaires can be subdivided intothree groups:- directive lighting: pictograms ortexts providing information- emergency lighting: lighting forescape routes, anti-panic lightingand emergency lighting for workplaces with special hazards- backup lighting: takes over thefunction of providing artificiallighting for maintaining opera-tions over a limited period

Applications

Projects:Palazzo della Ragione, BergamoPotsdamer Platz, BerlinNorwegian Aviation Museum,BodoGIRA, Radevormwald

For identifying:- exits- emergency exits, fire exits- escape and rescue routes

Directive luminaires are oftensecondary lighting features andshould match with the archi-tecture. Luminaires that changecolour allow controllable dynamicroute markings. Safety and rescuesign luminaires must comply withthe regional guidelines.





Lighting applications

E

Light plays a central and multi-faceted role in the design of avisual environment. In additionto the requirements and demandsmade by the user on lightingdesign, the architectonic conceptalso stipulates a framework forthe design of the illumination.Working plane Wall Ceiling

Floor Object Orientation lighting

Directive lighting




E GuideIndoor lighting | Lighting applications

Working plane

Work station Area, small Area, large

Illuminating a horizontal surfaceis one of the most common light-ing tasks. Most of the lightingtasks governed by work placestandards and standards forpedestrian traffic routes comeunder this category, whetherthese be the illumination of work surfaces or the actual floor.




Demanding visual tasks not onlyrequire general lighting butalso additional lighting for theworkstation.With task lights thelight can be directed to the task

in hand. Light structures withfluorescent lamps emit diffuselight.Directional luminaires emitan accentuating light onto theworkstation. Indirect light withuplights lends the room generalbackground lighting.

To provide an energy efficientlighting, the general lighting canbe lower than the illuminationof the working area. Combinedlighting with direct and indirectcomponents provides good visualcomfort both in the room and onthe work surface.

Observation

Conclusion

E GuideIndoor lighting | Lighting applications | Working plane

Work station

Task light

Light structure

Directional luminaire

Lighting criteria for task lighting- illuminance level dependent onactivity- illuminance distribution foravoiding direct- and secondaryglare- cut-off angle and position of the luminaire restrict glare andincrease visual comfort- the choice of lamp determinesthe light colour and colour ren-dition




Applications

Projects:Shanghai MuseumSuccess advertising agencyPalacio de la Aljaferia, ZaragozaFibanc, Barcelona


Work station

High luminances reflected fromsurfaces or objects cause second-ary glare. The luminaires shouldnot be positioned in the criticalareas. Indirect illumination with

diffuse light reduces the second-ary glare. When aiming the beamof light, care should be takento avoid shadows on the worksurface.

Arrangement

The quantitative lighting criteria

are primary considerations fortask lighting. Energy can be savedby reducing the general lightingin favour of local task lightingand daylight dependent control.

Preferred luminaire group- task lights- light structures- directional luminaires




Usable areas can be illuminateddirectly and indirectly: downlightsand pendant downlights emitdirect illumination into the room.Light structures have a diffuse

light distribution. Uplights illu-minate the room indirectly with adiffuse, uniform light.

Observation


Area, small

Light structures

Downlights

Pendant downlights

Uplights





Area, small

Applications

Projects:Dansk Design Center, CopenhagenDZ Bank, BerlinFibanc, BarcelonaFondation Beyeler, Basel

The quantitative lighting criteria

are paramount considerations forlighting usable areas.

Applications- office workstations- conference rooms- workshops and shopfloors- reception and entrance areas

Preferred luminaire groups- light structures- downlights- uplights

Compared to indirect lightingwith diffuse light, the directaimed light results in bettermodelling capability. Combinedlighting with direct and indirect

components ensures good visualcomfort both in the room and onthe work surface.

Conclusion Lighting criteria for usable areas:- illuminance level dependent onactivity- luminance distribution to avoiddirect and secondary glare

- cut-off angle and position of the luminaire restrict glare andincrease visual comfort- the choice of lamp determinesthe light colour and colour ren-dition




Under consideration of theenergy aspects, direct lightingwith permanently mounteddownlights are the most suitablefor large rooms.

Whereas downlights representfixed-location general lighting,spotlights can be used flexibly inthe area of exhibitions and pres-entations. Due to their narrow-beam light distribution, spotlightshave high glare control. Directedlight results in good modellingcapabilities.

Observation

Conclusion


Area, large

Downlights

Pendant downlights

Spotlights

Lighting criteria for usable areas:- illuminance level, depending onthe activity- luminance distribution to avoiddirect and secondary glare- cut-off angle and position of the luminaire restrict glare andincrease visual comfort- the choice of lamp determinesthe light colour and colour ren-dition




Applications

Projects:

Reichstag, BerlinBank of China, BeijingERCO, LüdenscheidStändehaus art gallery, Düsseldorf

The quantitative lighting criteriaare paramount considerationsfor lighting usable areas. Directillumination here is considerablymore economical than indirect

illumination.

General lighting for- workshops and shopfloors- museums- exhibitions- sales and representational areas

Preferred luminaire groups- downlights


Area, large




Wall, 3m Wall, 5m Wall with texture

Wall lighting can fulfil a numberof tasks. Firstly, it can be aimedat fulfilling vertical visual taskson the walls, whether this beinformative material such asnotice boards, presentationalobjects such as paintings or mer-chandise, architectonic structuresor the surface of the wall itself.Wall lighting can, however, alsobe aimed solely at presenting the

wall in its capacity as the surfacedelineating the room; finally,wall illumination can be a meansof indirect general lighting for aroom.


Wall




E GuideIndoor lighting | Lighting applications | Wall

Wall, 3m

Walls can be lit using point-formor linear luminaires. Wallwasherspotlights offer flexible adjust-ment for different wall heights.Wallwashers are characterised by

the even progression of bright-ness along the wall. Lens wall-washers have special lens reflec-tor systems. Washlights projectthe light evenly onto the wallsurface, while maintaining thedownlight effect on the room.Linear light sources for wall-

Observation

Point-form light sourcesWallwasher spotlights

washing with fluorescent lampsbrighten the wall with perfectuniformity. Using a Softec lensachieves an extremely even illu-mination of the whole wall even

in the higher area right up to theceiling. Perimeter illumination outof a haunch is positioned directlyon the wall. It produces a grazinglight effect emphasising the sur-face texture. The evenness of thewallwashing is only secondaryhere.

Point-form light sourcesWashlights

Point-form light sourcesLens wallwashers

Linear light sourcesWallwashers





Wall, 3m

Linear light sourcesLight structure

Linear light sourcesPerimeter luminaire

Linear light sourcesPerimeter luminaire Softec lens

Linear light sourcesPerimeter luminaire Cove

Conclusion Vertical i llumination emphasisesthe wall faces in terms of theirphysical make-up. The room ismade to look bigger by brighten-ing its walls and ceiling etc. Pointlight sources make the wall sur-face much more vivid, whereaswith linear luminaires a higheruniformity is achieved.

Lighting criteria for walls:- uniformity of the lighting- the choice of lamp determinesthe light colour and colour ren-dition





Wall, 3m

Arrangement The offset from the wall shouldbe at least one third of theroom height. Alternatively, theoffset from the wall is where a20 degree line projected from

the base of the wall intersectsthe ceiling. An optimum evennessis obtained when the luminairespacing is the same as the offsetfrom the wall. Wallwashers onlydevelop their optimal evennessas of a minimum number of three luminaires. The position of a wallwasher in a room cornershould lie on the 45° line.

Applications

Projects:British Museum, LondonCrescent House, WiltshireMediathek, SendaiWeimar College of Music

Washlighting illumination forvertical surfaces of:- museums- exhibitions

- trade-fair stands- sales and representational areas

Preferred luminaire groups- wallwashers- washlights- lens wallwashersdouble washlights- perimeter luminaires





Wall, 5m

In high rooms the luminaires arebeyond the direct field of vision.As the room height increases thebrightness of the wall decreases,if the lighting remains constant.

Wallwashers are characterisedby the even progression of brightness along the wall. Lenswallwashers have special lensreflector systems. Linear lightsources for wallwashing withfluorescent lamps provides aperfectly uniform brightening of

Observation

Point-form light sourcesWallwasher spotlights

the room. Using a Softec lens, anextremely even illumination of the whole wall can be achievedeven in the higher area rightup to the ceiling. The perimeter

illumination out of a haunch ispositioned directly on the wall. Itproducesa grazing light effect and empha-sises the surface texture. Theevenness of the wallwashing issecondary.






Linear light sourcesPerimeter luminaire Softec lens

Linear light sources

Perimeter luminaire Cove


Wall, 5m

Conclusion Vertical i llumination emphasisesthe walls – or other room limits– in terms of their physical make-up. The room is made to look big-ger by brightening the wall faces.Point-form light sources makethe wall surface much more vividwhile with linear luminaires ahigher uniformity is achieved. Asthe room height increases the dis-tance of the luminaire to the wallmust be increased. The reductionof the mean illuminance in higherrooms can be compensated forby having a higher lamp powerand by increasing the number of luminaires. Wallwashing only pro-duces an even brightness on mattsurfaces.

Lighting criteria for high walls- uniformity of the lighting- the choice of lamp determinesthe light colour and colour ren-dition




Arrangement Whereas for normal room heightsthe luminaire spacing is the sameas the offset from the wall, inhigher rooms it must be reducedto compensate for the other-

wise sinking illuminance. Theoffset from the wall is where a20 degree line projected fromthe base of the wall intersectsthe ceiling. The position of awallwasher at the end of the wallshould lie on the 45 degree line.


Wall, 5m

Applications

Projects:Heart of Jesus Church, MunichBank of China, BeijingBMW factory, LeipzigMartin-Gropius building, Berlin

Washlighting illumination forvertical surfaces in:- museums- exhibitions

- trade-fair stands- sales and representational areas

Preferred luminaire groups- wallwasher- washlights- lens wallwashers- perimeter luminaires





Wall with texture

Point-form wallwashers makesurface textures clearly visible.When using linear light sourcesthe wall face appears evenand the surface texture is only

emphasised to a limited extent.When using perimeter luminairesmounted directly on the wall,there is no evenness and greatvividness is created.

Observation

Point-form light sourcesDownlights



Linear light sourcesPerimeter luminaire Cove




Conclusion Linear light sources at a shortoffset from the wall most vividlyenhance the surface texture.Conversely, point-form lightsources at a short offset from

the wall produce their own lightpattern that, admittedly, doesaccentuate the texture, but doesnot permit an even wallwashing.Grazing light on walls can accen-tuate any surface irregularities.


Wall with texture

Applications

Projects:Burj Al Arab, DubaiConrad International Hotel,Singapore

ABN AMRO, SydneyHeart of Jesus Church, Munich

The smaller the offset from thewall, the clearer the surfacetexture is enhanced. When usinggrazing light, the evenness of the wall illumination is greatlyreduced.

Preferred luminaire groups

- wallwashers- washlights- lens wallwashers- perimeter luminaires




Ceiling, plan Structural elements

With ceiling illumination, eitherlight is shone to illuminate theceiling in its own right or the ceil-ing is merely used as a reflectorfor general lighting. The ceiling isprimarily emphasised, when it hasan intrinsic communicative value,e.g. due to architectonic struc-tures. Illuminating the ceiling toprovide indirect general lightingrequires it has a high reflectance.

It should be noted the ceiling willthen be the brightest surface inthe room and will therefore beemphasised.


Ceiling




E GuideIndoor lighting | Lighting applications | Ceiling

Ceiling, plan

The luminaires for washlightingthe ceiling can be mounted onthe walls or in the ground. Aslinear luminaires, light structuresact as independent architectural

elements, whereas ceiling wash-lights are more secondary to thearchitecture. Light structures emitdiffuse light with low brilliance.

Observation

Light structures

Ceiling washlights

Arrangement The prerequisite for ceiling illu-mination is a sufficiently highroom in order to achieve aneven distribution of light. Ceilingwashlights should be mountedabove eye-level. The distancefrom the ceiling depends on thelevel of evenness required andshould be at least 0.8m.

The choice of luminaire type isdependent on the ratio of roomarea to room height. In low roomswith large floor areas an evenillumination of the ceiling usinglight structures presents itself as the best option. Ceiling wash-lights require a large distancefrom the ceiling due to theirasymmetric light distribution.

Conclusion





Ceiling, plan

Applications

Projects:

Weimar College of MusicShanghai MuseumEzeiza Airport, Buenos Aires

Washlighting ceiling illumina-tion for- offices- historical buildings- churches

- theatres- passages

Preferred luminaire groups- ceiling washlights- uplights- light structures





Structural elements

Luminaires for lighting supportstructures can be mounted onthe structure itself, on the wallsor in the floor. A washlightingillumination adds emphasis to

the whole ceiling surface. Nar-row-beamed luminaires accen-tuate the support structure inparticular.

Observation

Light structures

Light structures with ceilingwashlights

Ceiling washlights

Spotlights




Applications

Project:Palacio de la Aljaferia, Zaragoza

Indirect ceiling lighting for- historical buildings- churches- theatres- passages

Preferred luminaire groups- spotlights

- light structures- ceiling washlights


Structural elements

The selection of the type of luminaire is dependent on thescale and the proportion of thesupport structure. Spotlightscan also be attached directly

to components of the supportstructure. The arrangement of the luminaires should be orientedaround the design of the supportstructure. Ceiling washlights, dueto their asymmetric light distribu-tion, require a larger offset fromthe ceiling.

Conclusion





Floor

For floor lighting, either wash-lighting is applied to the floorsurface alone or the room asa whole is illuminated withdownlights with direct light from

above. Floor washlights particu-larly highlight the floor surfaceand its physical make-up.

Observation

Downlights

Floor washlights

Due to their asymmetric light dis-tribution, floor washlights providegrazing light illumination of thefloor. They ensure a high degreeof visual comfort thanks to theirlow mounting height. The elimina-tion of glare from downlights isdetermined by the cut-off angle.The evenness of the downlightlighting is higher.

Conclusion





Floor

Applications

Projects:

Lamy Innovation Workshop,HeidelbergKonrad Adenauer Fund, Berlin

Floor washlighting for- walkways and foyers in hotels,theatres, cinemas and concerthalls- hallways

- steps and stairs

Preferred luminaire groups:- downlights- floodlights




Object in the space Object on the wall

Objects can be accentuated withgreat effect to turn them into realeye-catchers. Visual impressionscan be given an unusual appear-ance by selecting a crisp edgedillumination. The opposite of suchdramatic lighting is a uniform,large area lighting solution.


Object




E GuideIndoor lighting | Lighting applications | Object

Object in the space

Objects in the room or area canbe illuminated flexibly usingtrack-mounted spotlights orfloodlights. When illuminating anobject with one spotlight in the

direction of vision, the modellingeffect is weak. Two spotlights,with sculpture accessories, shin-ing from different directions cre-ate a balanced, three-dimensionaleffect. The brightness contrastsare milder compared to whenusing just one spotlight. Illumi-

Observation

Spotlight, front elevation

nating from below producesinteresting effects since the lightis coming from an angle which isunusual for the observer.

Spotlight, side elevation

Spotlight, isometric

Spotlight, underside




Floodlights

Narrow beam spotlights accentu-ate the object while floodlightsshow the object in the contextof its surroundings. This reducesthe modelling effect. Lightingfrom below can have the effect of making things look very strange.The possibility of dazzle must be

prevented here in particular.

Conclusion


Object in the space

Arrangement Objects in the room can be illumi-nated with an angle of incidenceof 30° to 45° to the vertical. Thesteeper the incident light, thestronger the shadows. When theangle of incidence is 30°, strongreflection or undesirable shad-ows on people and objects areavoided.

Applications

Projects:Passeig de Gràcia, BarcelonaMuseum of Contemporary Art,HelsinkiGuggenheim Museum, BilbaoHermitage, Saint Petersburg

Accent lighting for- museums- exhibitions- trade-fair stands- sales and representational areas

Preferred luminaire groups- spotlights- floodlights





Object on the wall

Objects on the wall can be flexiblyilluminated with track-mountedspotlights or floodlights. Spot-lights highlight the wall-mountedpicture and create a decorative

effect. Individual wallwashersaccentuate the picture morediscretely than spotlights. Sev-eral wallwashers illuminate thewall evenly. The object is notemphasised. Floodlights providea homogenous illumination of the entire wall surface. A contour

Observation

Spotlights

spotlight ensures very strong,effective emphasis of the wall-mounted picture.

Wallwasher spotlights

Floodlights

Contour spotlights





Object on the wall

Narrow beam spotlights accentu-ate the object while floodlightsshow the object in the context of its surroundings. Contour spot-lights can illuminate the object

with a crisp focused beam andthus highlight particularly well.This can result in an effect thatmakes the object look strangebecause the object itself seemsto emit light.

Conclusion

Arrangement Objects on the wall can be illumi-nated with an angle of incidenceof 30° to 45° to the vertical. Thesteeper the incident light, themore vivid the object appears. Onreflective surfaces, e.g. artworksbehind glass or oil paintings, caremust be taken that the angle of

incidence does not cause second-ary glare in the observer‘s lineof vision. In addition, unwantedshadow, e.g. cast by the pictureframe onto the picture surface,should also be avoided.

Applications

Projects:Museum of Contemporary Art,BarcelonaMuseo Deu, El VendrellPalacio Real de MadridReichstag, Berlin

Accent lighting for- museums- exhibitions- trade-fair stands- sales and representational areas

Preferred luminaire groups- spotlights- wallwashers- floodlights





Orientation lighting

Floor washlights




Orientation lighting is definedfirst and foremost by the task of providing orientation. This canbe done using luminaires thatprovide visibility or ones that act

as a sign. Floor washlights andwall-mounted downlights provideorientation by illuminating eitherthe floor surface or the room. Ori-entation luminaires and recessedfloor luminaires typically provideorientation by being arrangedinto lines or by marking out areas.

Observation





Orientation lighting

Low illumination levels are suf-ficient for orientation purposes.Small luminaires with high lumi-nance clearly set themselvesapart form their surroundings.

Conclusion

Applications

Projects:Light and Building, FrankfurtPalazzo della Ragione, BergamoDeutsche Bank, Tokyo

Sevens, Düsseldorf

Orientation lighting for theidentification of - architectural lines- steps and exclusion zones- entrances- routes- emergency exit routes

Preferred luminaire groups- floor washlights- wall-mounted downlights- recessed floor luminaires- orientation luminaires





Directive lighting

Applications

Projects:Palazzo della Ragione, BergamoBurj Al Arab, DubaiNorwegian Aviation Museum,BodoTaschenberg-Palais, Dresden

Application: for identification of:- exits- emergency exits, fire exits- escape and rescue routes

Directive luminaires are oftensecondary lighting features andshould match with the archi-tecture. Luminaires that changecolour allow controllable dynamicroute markings. Safety and rescue

sign luminaires must comply withthe regional guidelines.

Preferred luminaire groups- directive luminaires- safety sign luminaires- luminaires for pictograms

Observation Directive luminaires provide infor-mation or give directions by wayof pictograms and inscriptions.Safety and rescue sign luminairesinform on the direction of an

escape route or emergency exit.




GuideOutdoor lighting

E

Outdoor lighting concepts canform a continuous whole withthe indoor lighting designs. Lumi-naires built to high protectionmode form the basis for addingdramatic lighting to architecture,cityscapes and vegetation bynight.Types of lighting Luminaire groups Lighting applications

Design examples Lighting design




The effect of rooms, facades,objects and vegetation greatlydepends on the type of lighting.This ranges from general lightingthrough to specific highlighting.Washlighting forms the back-ground for accent lighting foremphasising objects. In terms of orientation lighting, points of light or rows of lights are usedto provide orientation in the

outdoor area.

E GuideOutdoor lighting

Types of lighting

General Washlighting Accentuation

Orientation




E

General lighting designates aneven illumination related to ahorizontal working plane or pedes-trian traffic zones. Quantitativeaspects are often a primary con-sideration. Direct lighting permitsboth diffuse and directed light.

direct, aimed direct, diffuse

GuideOutdoor lighting | Types of lighting

General




A direct and aimed general light-ing produces an even illumina-tion on the horizontal workingplane. The architecture is visibleand it is possible to orientate

oneself in the room.


modelling and brilliance. Theuniformity on the working planeincreases as the mounting heightincreases or as the beam anglewidens. Directed light enablesgood appreciation of form andsurface texture. The visual com-fort increases as the cut-off angleincreases. A feature of direct illu-mination is its highly efficientuse of energy.

Observation

E

Conclusion

Projects:Repsol petrol station, SpainCongress Palace, ValenciaFederal Chancellery, BerlinCity Hall, London

GuideOutdoor lighting | Types of lighting | General

direct, aimed

Applications Downlights cater for an even lightdistribution on the horizontalplane. They have an inconspicuousdesign and can be integrated wellinto the architecture.

Direct, directed general lightingfor:- entrance areas- arcades- passages- atria

Preferred luminaire group- downlights




E GuideOutdoor lighting | Types of lighting | General

direct, diffuse

A direct, diffuse general lightingdesignates an even illuminationwith respect to a horizontal work-ing plane. The architecture is vis-ible and it is possible to orientate

oneself in the room.

Direct, diffuse light produces

a soft illumination with littleshadow and reflection. The lim-ited formation of shadow resultsin weak modelling capabilities.Shapes and surface textures areonly slightly emphasised. Onefeature of using fluorescentlamps for the general lightingis an efficient use of energy.

Observation

Conclusion

Projects:Private residence, RavensburgPrivate residence, RavensburgBodegas Vega Sicilia Wine Cellar, Valladolid

Applications Direct, diffuse general lighting for- entrance areas- overhanging or cantileveredroofs

- floor lighting on access drive-ways, paths and public squares

Preferred luminaire groups- downlights- wall-mounted downlights




E

Washlighting illumination refersto an architecture-related andobject-orientated illumination.The primary purpose is to makevisible the room proportions androom limits. Symmetrical flood-lights are used for washlightingof horizontal surfaces or forgeneral lighting in the area of presentation. A feature of asym-metrical floodlights is the uni-

form light intensity distributionon surfaces.

symmetrical asymmetrical

GuideOutdoor lighting | Types of lighting

Washlighting




E GuideOutdoor lighting | Types of lighting | Washlighting

symmetrical

Symmetrical washlighting pro-duces an even illumination onobjects or surfaces. Washlightillumination is characterised byhigh uniformity and a soft gradi-

ent of light intensity distribution.The illuminated areas of the roomare emphasised by washlighting.


modelling abilities and enablesgood appreciation of form andsurface structure. Washlightingillumination can serve as a back-ground for accent lighting.

Observation

Conclusion

Projects:Private residence, SouthernHighlands, AustraliaERCO Lightpark, LüdenscheidChurch, RörvikMonastery ruins, Paulinzella

Applications Washlighting illumination for:- wall lighting- facades- entrance areas

- cantilever roofs- trees- park and garden complexes- sculptures- objects

Preferred luminaire group- floodlights





asymmetrical

Asymmetrical washlighting illu-mination is used for illuminatingsurfaces evenly. Wallwashing isa highly valued tool in architec-tural lighting. Vertical illumina-

tion emphasises the walls – orother room limits – in terms of their physical make up. Brighten-ing the wall surfaces makes theroom look bigger.

Observation

Wallwashers

Recessed luminaires

Floor washlights




Projects:Regional government of LowerSaxony and Schleswig-Holsteinin BerlinKaufhof media facade, HamburgMuseo del Teatro de Caesar-augusta, ZaragozaPorches de la Boquería, Barcelona

Applications Washlighting illumination for- facades- entrance areas- passages- atria- cantilever roofs- park and garden complexes

Preferred luminaire groups- floodlights- washlightswallwashers- recessed floor luminaires

Point-form luminaires lend the

wall surface a higher brillance,whereas with linear luminairesa higher uniformity is achieved.With asymmetrical washlighting,areas of a room can be definedand thus have attention attractedto them. It can also serve as abackground for accent lightingor form the ambient brightnessfor the work place. To obtain auniform light intensity distribu-tion the correct positioning of theluminaires is of great importance.

Conclusion



asymmetrical




Accent lighting enables goodappreciation of form and surfacestructure. The focused light pro-duces pronounced shadows andgood modelling ability, as well asbrilliance. A narrow beam and ahigh brightness contrast to thesurroundings give the object par-ticular emphasis.

Conclusion

Projectors

E GuideOutdoor lighting | Types of lighting

Accentuation

Highlighting emphasises indi-vidual objects or architecturalelements. This makes it possibleto establish a hierarchy of hownoticeable each item is and to

attract attention.

Observation





Projects:

ERCO Lightpark, LüdenscheidERCO, LüdenscheidSri Senpaga Vinayagar Temple,SingaporeTommy Hilfiger, Düsseldorf

Applications Accent lighting creates points of interest. Structures and texturesof objects are clearly emphasisedby the directed light.Accent lighting for:

- facades- entrance areas- arcades- park and garden complexes- objects

Preferred luminaire groups- projectors- directional luminaires


Accentuation




Floor washlights

E Guide

Outdoor lighting | Types of lighting

Orientation

Orientation lighting is definedfirst and foremost by the task of providing orientation. This can beachieved by luminaires that func-tion as sources of illumination or

as signals. Illuminating the roomis of secondary importance here;instead, a row of these luminairesis typically arranged to form anorientation line.

Observation






Low illumination levels are suf-

ficient for orientation purposes.Small luminaires with high lumi-nance clearly set themselvesapart form their surroundings.

Conclusion



Orientation

Projects:Sevens department store,Düsseldorf Hilton Hotel, DubaiBathing platform Kastrup Sobad,CopenhagenPrivate residence, Palamos

Applications Orientation lighting for theidentification of - architectural lines- steps and exclusion zones

- entrances- routes- emergency exit routes

Preferred luminaire groups- floor washlights- wall-mounted downlights- recessed floor luminaires- orientation luminaires




E

Luminaires are available in a widevariety of types, each intended tofulfil different lighting require-ments. For external applications itis primarily permanently mountedluminaires that are used.

Projectors Floodlights


Luminaire groups

Wallwasher

Luminaires for openarea and pathwaylighting

Downlights Ceiling and wall-mounted downlights

Recessed floorluminaires

Orientationluminaires




Projectors illuminate a narrowlyconstrained area. The type of mounting and the orientation arevariable. Projectors are offeredwith different beam emission

angles and light distributions.

Criteria for projectors- choice of lamp determines lightcolour, brilliance, functional life,light intensity

Light

Projectors have narrow-beamlight distribution with a rotation-ally symmetrical beam.

The use of accessories is alsotypical for projectors:- lenses: spread lenses or sculp-ture lenses

- filter: colour filter, UV or IRfilter- glare control: anti-dazzle screen

E GuideOutdoor lighting | Luminaire groups

Projectors

- emission angle determines thebeam of light and is defined bythe reflector and the lamp- cut-off angle limits glare andincreases visual comfort

- rotatable and tiltable

Applications

Projects:Norwegian Aviation Museum,BodoERCO Lightpark, LüdenscheidERCO Lightpark, LüdenscheidERCO, Lüdenscheid

Accent lighting for:- facades- entrance areas- arcades

- park and garden complexes- objects




Floodlights have a wide-beamcharacteristic. They are offeredwith a axially symmetrical orasymmetrical light distribution.

Criteria for floodlights- choice of lamp determines lightcolour, functional life, efficiency,light intensity- uniformity: optimised reflectorfor even illumination of areas

Light

Floodlights, axially symmetricalFloodlights with axially symmetri-cal light distribution provide evenillumination of objects or areas.Light distribution with focalemphasis.


Floodlights

- gradient: soft edge to the beamof light- light output ratio is increased byoptimised reflector technology

Applications

Projects:Private residence, SouthernHighlands, AustraliaERCO Lightpark, LüdenscheidCentenary Hall, BochumSri Senpaga Vinyagar Temple,Singapore

Washlighting provides an evenillumination for:- wall lighting- facades- entrance areas- overhanging or cantileveredroofs- park and garden complexes- sculptures- objects

Surface-mounted luminairesact as features themselves. Theirarrangement should match theirsurroundings.

Floodlights, asymmetricalFloodlights with asymmetricallight distribution provide evenillumination of areas. The lumi-naires can be mounted on walls,ceilings or floors and in additioncan also be tilted.




Wallwashers have a wide-beamcharacteristic. They are offeredwith an asymmetric light distri-bution.

Criteria for wallwashers:- choice of lamp determines lightcolour, functional life, efficiency,light intensity- uniformity: optimised reflectorfor even illumination of areas- gradient: soft edges to the beamof light

Light

WallwashersRecessed-mounted wallwasherswith asymmetric light distribu-tion provide an even illuminationof areas.


Wallwasher

- light output ratio is increased byoptimised reflector technology

Applications

Projects:Regional government of LowerSaxony and Schleswig-Holstein,BerlinKaufhof Media Facade, HamburgERCO P1, LüdenscheidConcentration Camp memorial,Belzec

Wallwashing is an importantcomponent of architecturallighting for adding emphasis tofacades. Further applications are:- entrance areas- passages- atria- overhanging or cantileveredroofs- park and garden complexes

As recessed luminaires, wall-washers are inconspicuous archi-tectural details. Surface-mounteddownlights act as a room feature.They should correspond to thearchitecture in their arrangementand form.

Wallwasher, tiltableRecessed-mounted wallwasherswith asymmetric light distribu-tion provide an even illumina-tion of areas. Surface-mounteddownlights can be mounted onwalls, ceilings or floors and inaddition can also be tilted.




Luminaires for open area andpathway lighting have a wide-beam characteristic. They areoffered with an asymmetric lightdistribution.

Criteria for luminaires for openarea and pathway lighting- choice of lamp determines lightcolour, functional life, efficiency,light intensity- uniformity: optimised reflectorfor even illumination of areas- gradient:soft edges to beam of light- cut-off angle increases visualcomfort and limits glare and lightpollution

Light

Luminaires for pathway

lightingPathway lighting luminaires withasymmetric light distributionprovide uniform illumination onpathways. The light is spread inits width so that pathways canbe evenly illuminated. Their smalldesign makes these luminairessuitable for lighting steps.


Luminaires for open area and pathway lighting


Luminaires for open arealightingLight for illuminating open spacesis generated by an asymmetric

reflector-flood system. A sculp-ture lens acting as safety glassdirects the light deep into theoutdoor area.

Facade washlightsFloor washlights with asymmetriclight distribution provide an evenillumination of buildings.




Applications

Projects:

Panticosa resort, PanticosaPrivate residence, BerlinERCO, LüdenscheidArt hall, Emden

Luminaires for open area andpathway lighting are mainly usedfor illuminating the following:- facades- entrance areas

- arcades- passages- floor lighting on access drive-ways, paths and public squares- orientation lighting on path-ways, drives, entrances and steps- park and garden complexes

As recessed luminaires, theseare inconspicuous architecturaldetails. Free-standing luminairesact as features in the room. Theirarrangement should correspondto the surroundings.


Luminaires for open area and pathway lighting




Downlights emit a beam that isdirected downwards at either aperfectly vertical or an adjustableangle. They are usually mountedon the ceiling and illuminate the

floor or walls. They are offeredwith narrow-beam, wide-beam,symmetric or asymmetric lightdistribution. The cut-off angle of narrow-beam downlights meansthey are largely free of glare. Ondownlights with Darklight reflec-tor, the lamp‘s cut-off angle isidentical to that of the luminaire.This gives a luminaire with thewidest beam possible while simul-taneously having an optimisedlight output ratio. The use of adiffuser reduces the luminancein the luminaire and therebyimproves the visual comfort andthe evenness.

Light

DownlightsDownlights have a rotationallysymmetric beam that is directedvertically downwards.


Downlights

Criteria for downlights- choice of lamp determines lightcolour, functional life, efficiency,light intensity- emission angle determines the

beam of light and is defined bythe reflector and the lamp- cut-off angle limits glare andincreases visual comfort- light output ratio is increased byoptimised reflector technology

Directional luminairesDirectional luminaires providehighlighting for individual areasor objects with a medium tonarrow light distribution.




Applications

Projects:Repsol petrol station, SpainCongress Palace, ValenciaFederal Chancellery, BerlinCity Hall, London

Downlights provide general light-ing for- entrance areas- arcades- passages- atriaRecessed downlights are incon-spicuous architectural details,whereas surface-mounted down-lights and pendant luminairesact as room features. They should

correspond to the architecture intheir arrangement and design.

The offset from wall shouldmeasure approximately half of the luminaire spacing in order toachieve sufficient brightness onthe wall and well proportioned

scallops of light. To attain an evenillumination on a reference plane,the luminaire spacing should notexceed the mounting height hby more than 1.5:1. An optimalevenness is achieved when a=h.

Arrangement


Downlights




Ceiling and wall-mounteddownlights are defined firstand foremost by their type of mounting and not by their lightcharacteristics. They are available

with narrow-beam, wide-beam,symmetrical or asymmetric lightdistribution. Some luminairescan be positioned either on thewall or on the ceiling.

Criteria for ceiling and wall-mounted downlights- choice of lamp determines lightcolour, functional life, efficiency,light intensity- uniformity: optimised reflectorfor even illumination of areas

Light

Facade luminaires

Facade luminaires are offeredwith narrow-beam, wide-beam,symmetrical or asymmetric lightdistribution. The light can be dis-tributed either via a single-sidedor double-sided light aperture.


Ceiling and wall-mounted downlights

- cut-off angle increases visualcomfort and limits glare and lightpollution

Wall-mounted downlightsWall-mounted downlights, withtheir diffuse beam in the room,provide good visual comfort.

They can also be mounted onthe ceiling.

Wall-mounted downlights,shieldedWall-mounted downlights withhalf-shielded face offer goodvisual comfort and illuminatethe floor area in particular.




Applications

Projects:

Private residence, RavensburgPrivate residence, RavensburgZara, MunichCultural Centre and CoastalMuseum NORVEG, Rörvik

For illumination of:- facades- entrance areas- overhanging or cantileveredroofs

- floor lighting on access drive-ways, paths and public squares

The position and design of theceiling and wall-mounted down-lights should be chosen to matchthe with the architecture. Facadeluminaires should be arrangedsuch that the elements to be illu-minated are optimally lit and nolight shines past the objects.


Ceiling and wall-mounted downlights




Recessed floor luminaires emittheir beam upwards. They areoffered with narrow-beamed,wide-beamed, symmetric orasymmetric light distribution.

Criteria for recessed floor lumi-naires:- choice of lamp determines lightcolour, functional life, efficiency,light intensity- uniformity with wallwashers:optimised reflector for even illu-mination of areas- range of tilt for directionalluminaires with high glare pro-tection

Light

Uplights

Uplights feature an upwardsdirected beam with symmetricallight distribution. The narrow,rotationally symmetrical beamis used for highlighting objects.




Lens wallwashersLens wallwashers feature anupwards directed beam withasymmetrical light distribution.

They provide an even illumina-tion of walls.

Directional uplightsDirectional luminaires providehighlighting for individual areasor objects with a medium to nar-row light distribution. The beamcan be titled.

Uplight, diffuseRecessed floor luminaires withdiffuse light intensity distributionare used for marking paths oremphasising architectural lines.




Applications

Projects:

Glass pavilion, Glass technicalcollege, RheinbachBrandenburg Gate, BerlinKhalil Al-Sayegh, DubaiBenrath Castle, Düsseldorf

Accent lighting or floodlightingfor- facades- entrance areas- arcades

- passages- atria- overhanging or cantileveredroofs- park and garden complexes

Recessed floor luminaires areinconspicuous architecturaldetails. They should correspondto the architecture in theirarrangement and form.






Orientation luminaires aredefined first and foremost bythe task of providing orientation.This can be achieved by lumi-naires that function as sources

of illumination or as signals.

Criteria for orientation luminaires- luminance: noticability of theluminaires in their surroundings

Light


Orientation luminaires withpoint-form front lens act asa local orientation light.



Floor washlightsFloor washlights form points of light on the wall and serves asan orientation light on the floor

surface.




Applications

Projects:

Sevens department store,Düsseldorf Hilton Hotel, DubaiBathing platform Kastrup Sobad,CopenhagenPrivate residence, Palamos

For identifying:- architectural lines- steps or restricted areas- entrances- routes

- emergency exit routes







Lighting applications

E

Illuminating facades by nightchanges the atmosphere of acity. In urban areas or civic parks,points of interest can be createdto enable orientation and toestablish spatial reference points.Light in the outdoors also extendsone‘s perception when lookingoutside from with a building.

Wall Ceiling Floor

Object Facade Vegetation




E GuideOutdoor lighting | Lighting applications

Wall

Wall, 3m Wall, 5m Wall with texture

Wall and facade lighting at nightextends one‘s perception anddefines spatial limits. Verticalillumination is significant in thevisual surroundings for identify-ing areas in terms of their form,regardless of whether they arefacades or walls covered withclimbing plants. The objectivemay be to obtain a uniformwallwashing comparable to that

in the indoor area, or to gentlyilluminate a building againstthe nocturnal environment. Thearrangement of the luminairesis dependent on the desireduniformity and illuminance. Inthe outdoor area at night, a lowbrightness is often sufficient formaking objects visible and formaking contrasts.




Wallwashers are noted for givingan even progression of brightnesson the wall.

Vertical i llumination emphasisesthe surfaces delineating the roomin terms of their physical makeup.The room is made to look biggerby brightening the wall faces.Point-form light sources makethe wall surface much more vivid.Wallwashing only achieves a uni-form brightness on matt surfaces.

Lighting criteria for walls:- uniformity of the lighting- the choice of lamp determinesthe light colour and colour rendi-tion

Observation

Conclusion

E GuideOutdoor lighting | Lighting applications | Wall

Wall, 3m

Wallwashers, plan view

Wallwasher, underside

Recessed-mounted washlight




Applications

Projects:ERCO, LüdenscheidBenrath Castle, Düsseldorf Berliner Tor Center, HamburgConcentration Camp memorial,Belzec

The offset from the wall shouldbe at least one third of the wallheight. Alternatively, the light‘sangle of incident should be 20°to the vertical. An optimum

evenness is obtained when theluminaire spacing is the same asthe offset from the wall, or atleast does not exceed it by morethan 1.5 times. Wallwashers onlydevelop their optimal evennessas of a minimum number of threeluminaires.

Arrangement

Washlighting illumination forvertical surfaces of:- wall lighting- facades- entrance areas

Preferred luminaire groups- wallwashers


Wall, 3m




Given the same lighting, asthe wall height increases thebrightness of the wall decreases.Wallwashers are characterised bythe even progression of bright-

ness along the wall. Lens wall-

Vertical i llumination emphasisesthe wall faces in terms of theirphysical makeup. The room ismade to look bigger by brighten-ing its walls and ceiling. Directedlight makes the wall surface muchmore vivid. As the wall heightincreases the distance of theluminaire to the wall must beincreased. The reduction of themean illuminance on the wallcan be compensated for by hav-ing a higher lamp power and byincreasing the number of lumi-naires.

Lighting criteria for high walls:- uniformity of lighting- the choice of lamp determinesthe light colour and colour rendi-tion

Observation

Conclusion


Wall, 5m

Wallwashers

Lens wallwashers

washers have special lens reflec-tor systems.




Applications

Projects:Regional government of LowerSaxony and Schleswig-Holsteinin BerlinGeorg Schäfer Museum,SchweinfurtBrandenburg Gate, BerlinSacred Heart church, Munich

Whereas for normal wall heightsthe luminaire spacing is the sameas the offset from the wall, forhigher walls it must be reducedto compensate for the otherwise

sinking illuminance. The offsetfrom the wall is given where a 20°line projected down from the topof the wall meets the ground.

Arrangement

Washlighting illumination forvertical surfaces of:- wall lighting- facades- entrance areas

Preferred luminaire groups- wallwashers- lens wallwashers


Wall, 5m





Wall with texture

Point-form light sources at ashort offset from the wall pro-duce their own light pattern that,admittedly, does accentuate thetexture, but does not permit an

even wallwashing. Grazing light

Directed grazing light makessurface textures clearly visible.

Observation

Conclusion

Downlights

Wallwashers

Lens wallwashers

on walls can emphasise any sur-face irregularities.





Applications

Projects:

Rohrmeisterei restaurant,SchwerteSri Senpaga Vinayagar TemplePrivate residence, Germany

The smaller the offset from thewall, the clearer the surfacetexture is enhanced. When usinggrazing light, the evenness of the wall illumination is greatly

reduced.

Preferred luminaire groups- downlights, narrow-beamed- wallwasher- recessed floor luminaires(uplights, lens wallwashers,directional luminaires)


Wall with texture




Ceiling, plan Structural elements

With ceiling illumination, eitherlight is shone to illuminate theceiling in its own right or the ceil-ing is merely used as a reflectorfor general lighting. The ceilingis primarily emphasised, when ithas an intrinsic communicativevalue, e.g. due to architectonicstructures.


Ceiling




E GuideOutdoor lighting | Lighting applications | Ceiling

Ceiling, plan

The luminaires for washlightingthe ceiling can be mounted onthe walls or in the ground.

Observation

Uplights


Conclusion Selecting the luminaire type isdependent on the room and itsuse. For ceiling washlights, a min-imum distance to the ceiling is

required. To avoid glare, recessedfloor spotlights for illuminatingceilings should not be installedin heavily trafficked areas.

Arrangement The prerequisite for ceiling illumi-nation is a sufficiently high roomin order to achieve an even dis-tribution of light. Ceiling wash-lights should be mounted aboveeye-level. The distance from theceiling depends on the level of evenness required and should beat least 0.8m.




Applications

Projects:

Stansted Airport, LondonGlass pavilion, Glass technicalcollege, RheinbachJahrhunderthalle, BochumCosmo petrol station, Tokyo

Washlighting ceiling illumina-tion for- entrance areas- arcades- passages

- atria- overhanging or cantileveredroofs

Preferred luminaire groups- ceiling washlights- recessed floor spotlights


Ceiling, plan




Luminaires for lighting supportstructures can be mounted onthe structure itself, on the wallsor in the floor. A washlightingillumination adds emphasis to the

whole ceiling surface. Narrow-beamed luminaires accentuatethe support structure in particu-lar.

Observation

Spotlights

Floodlights

Recessed floor luminaires,directional luminaires


Structural elements




Recessed floor luminaires,uplights

Conclusion The selection of the type of lumi-

naire is dependent on the scaleand the proportion of the supportstructure. Spotlights can also beattached directly to componentsof the support structure. Thecomplete support structure canbe illuminated with floodlights.To avoid glare, recessed floorspotlights for lighting the supportstructure should not be installedin heavily trafficked areas. Thearrangement of the luminairesshould be oriented around thedesign of the support structure.


Structural elements

Applications

Projects:Burj Al Arab, DubaiCiudad de las Artes y las Ciencias, ValenciaPetronas Twin Towers, KualaLumpurMuseo del Teatro de Caesar-augusta, Zaragoza

Ceiling lighting for:- entrance areas- arcades- passages- atria- overhanging or cantileveredroofs

Preferred luminaire groups- spotlights- ceiling washlights- recessed floor luminaires




When floor lighting, the floorsurface can be illuminated withdirect light from downlights orfrom floodlights positioned onthe sides. Floor washlights partic-

ularly emphasise the floor surfaceand its physical make-up.

Observation

Pathway luminaires

Luminaires for open-area lighting

Downlights

Downlights, narrow-beamed


Floor




Conclusion Due to their asymmetric light dis-tribution, floor washlights providegrazing light illumination of thefloor. They ensure a high degreeof visual comfort thanks to theirlow mounting height. A soft beamgradient reduces the contrastwith the surroundings. The elimi-

nation of glare from downlights isdetermined by the cut-off angle.

Applications

Projects:ERCO, LüdenscheidGreater London AuthorityPrivate residence, BerlinPrivate residence, Palamos

Floor washlighting for:- driveways- pathways- public squares

Preferred luminaire groups:- downlights- floor washlights- bollard luminaires- mast luminaires


Floor

Floor washlights




Object, free-standing Objects on the wall

Objects can be accentuated withgreat effect to turn them into realeye-catchers. The appearance of objects can be made to look unu-sual by selecting a strong grazinglight. The opposite of such dra-matic lighting is a uniform, largearea lighting solution.


Object




Objects in the room or area canbe illuminated with spotlights orfloodlights. When illuminating anobject head-on with one spot-light in the direction of vision,

the modelling effect is weak.Two spotlights, with sculptureaccessories, shining from differ-ent directions create a balanced,three-dimensional effect. Thebrightness contrasts are mildercompared to when using justone spotlight. Illuminating from

Observation

Spotlights

below produces an interesting butmysterious effect since the lightis coming from an angle which isunusual for the observer.

Floodlights

E GuideOutdoor lighting | Lighting applications | Object

Object, free-standing


Directional uplights




Applications

Projects:Norwegian Aviation Museum,BodoERCO, LüdenscheidRhenish State Museum, BonnLet The Dance Begin, Strabane

Accent lighting for- park and garden complexes- sculptures

Preferred luminaire groups- spotlight- floodlights


Object, free-standing

Arrangement Objects in the room can be illumi-nated with an angle of incidenceof 30° to 45° to the vertical. Thesteeper the incident light, thestronger the shadows.

Narrow-beam spotlights placeemphasis on the object alone,whereas floodlights show theobject in the context of its sur-roundings. This reduces the

modelling effect. Lighting frombelow can have the effect of making things look very strange.

Conclusion




Objects on the wall can be illumi-nated with spotlights or flood-lights. Spotlights highlight theobject and create a decorativeeffect. Due to their even illumina-

tion of the complete wall surface,

Observation floodlights accentuate the objectless than spotlights.


Objects on the wall

Spotlights

Floodlight from above

Floodlight from below

Recessed floor and directionalluminaire

Lens wallwashers




Narrow-beam spotlights accentu-ate the object while floodlightsshow the object in the context of its surroundings.

Conclusion

Applications

Projects:ERCO, Lüdenscheid Vietnam Veterans Memorial,Washington DCSinnet Tennis Club, Warsaw

Accent lighting for- facades- entrance areas- park and garden complexes

- sculptures

Preferred luminaire groups- spotlight- wallwashers- uplights

Arrangement Objects on the wall can be illumi-nated with an angle of incidenceof 30° to 45° to the vertical. Thesteeper the incident light, themore three-dimensional theobject appears.


Objects on the wall




Solid facade Facade, verticallydivided

The form of facades is determinednot only by their material andshape but also by the light and itsdirection and colour. The appear-ance of a facade alters duringthe course of the day due to thechanging direction of light andthe varying components of dif-fuse and direct light. Differentlight distributions and the useof lighting control systems give

facades an appearance of theirown at night. Varying illumi-nances differentiate componentsor areas of a facade. Grazing lightemphasises facade details. Wash-lighting facades allows them toappear in their entirety. Shiningany light beyond the facade sur-faces, either to the sides or overthe top, should be avoided.


Facade

Horizontally dividedfacade

Facade with projectingor recessed sections

Perforated facade Banded facade

Transparent facade




Washlighting creates a very uni-form light distribution on thefacade. A line of light marks outthe edge of the building againstthe night sky. Uplights rhythmi-

cally divide up the facade. Under

Observation

Floodlight, below

the light of up-downlights,graphic patterns are produced bythe definite beams.

Line of light, above

Uplights

Facade luminaires downlights

E GuideOutdoor lighting | Lighting applications | Facade

Solid facade

Facade luminaires uplights anddownlights




Washlighting facades can makethem appear flat. Reducing theilluminance as the facade heightincreases gives a low-contrasttransition to the dark night sky.

Grazing light emphasises thesurface textures of materials.Progressions of light on untex-tured walls become the dominat-ing feature and are seen as inde-pendent patterns in their ownright. Large, uniform surfaces canbe given structure with patterns

Conclusion

Arrangement The facade lighting can be posi-tioned on the ground, on a mastor on the building. Wallwashersoffset from the facade at onethird to half the facade heightavoid long shadows. Luminairespositioned close to the facadeproduce grazing light with a

strong emphasis on the surfacetextures and structures. Recessedfloor luminaires are architectur-ally discrete. Overgrown vegeta-tion must be prevented. Mast

of light. Beams of light that donot match or correspond withthe architecture are perceived asdisturbing.


Surface-mounted floor luminaires

Upright supporting tube


Solid facade

luminaires will appear as additivefeatures in front of the facade.Cantilever arms allow directmounting to the building. Shiningany light beyond the facade sur-faces, either to the sides or overthe top, should be avoided.




Applications

Projects:Georg Schäfer Museum,SchweinfurtERCO Lightpark, LüdenscheidERCO Lightpark, LüdenscheidCultural Centre and CoastalMuseum NORVEG, Rörvik

Mast

Cantilever arm


Solid facade

Facade luminaires




Floodlights produce a uniformillumination on the facade.Washlighting with point-shapedlight sources makes the surfacetexture and structure clearly vis-

ible. Accentuating the columnsdetaches these from the surround-ing facade. Uplights positioned ontwo sides emphasise the volumeof the column. Downlights accen-tuate the column and illuminatethe floor area. The combinationof uplights and downlights aug-

Observation

Floodlights

ments the vertical facade divisionby lighting from above and below.

Uplights

Uplights, double-sided layout

Downlights


Facade, vertically divided




Downlights and uplights


Facade, vertically divided

Narrow beams of light intensifythe effect of the vertical divi-sion. To avoid shadows at theside, the luminaires should bepositioned at right angles, paral-lel to the facade. Strong con-trasts and heavy shadow can becompensated for by washlighting

the facade as a form of generallighting. The luminaires shouldbe positioned in a rhythm corre-sponding to that of the facadedivisions.

Conclusion

Applications

Projects:Brandenburg Gate, BerlinMunicipal works, LüdenscheidRuhr Festival Theatre CongressCentre, RecklinghausenFaena Hotel, Buenos Aires




Floodlights illuminate the entirefacade and emphasise the hori-zontal divisions by casting heavyshadows. Lines of light echo thehorizontal structure on the darker

facade surface.

Observation

Floodlights

Lines of light


Horizontally divided facade

Luminaires positioned close tothe facade highly emphasiseits three-dimensional nature.Long heavy shadows cast by

facade divisions can be reducedby increasing the offset of the

Conclusion luminaire from the facade. Thesteeper angle of incidence for thelight in the upper region of thefacade casts longer shadows than

in the lower area.

Applications

Projects:Millennium Grandstand, DubaiHong Kong and Shanghai Bank,Hong KongPalazzo della Borsa, TriestKaufhof department store,Mönchengladbach





Facade with projecting or recessed sections

Wide-beam floodlights set farfrom the building illuminate thefacade evenly. Facades with largeprotruding sections or insets willfeature heavy shadows. Differ-

ent illuminances or light coloursaugment the differentiation of the facade. Uplights mark outthe internal corners with grazinglight.

Observation

Floodlights

Spotlights with differentilluminances

Spotlights with different lightcolours

Uplights




Applications

Projects:Museum of Arts and Crafts,HamburgPalacio de la Aljaferia, Zaragoza

Differentiated illuminances, lightdistributions and light coloursadd rhythm to the appearanceof the facade. Harsh contrastsbetween accentuated and unlit

areas can be compensated for byusing washlighting to performthe general lighting. Increasingthe luminaire offset from thefacade reduces the formationof heavy shadow. The luminairearrangement should correspondto the pattern of facade division.

Conclusion


Facade with projecting or recessed sections





Perforated facade

Under daylight conditions thewindow surfaces appear dark.At night, illuminated interiorsprovide a strong contrast betweenthe dark facade surface and bright

windows. Floodlights produce uni-form light distribution over thefacade. Illuminating the windowembrasure accentuates the frameof the facade opening, whereasnarrow-beam uplights emphasisethe facade‘s grid pattern.

Observation

Daylight

Downlights, indoor

Floodlights

Lines of light




Applications

Projects:Humboldt-University, Ehrenhof,BerlinPentacon Tower, DresdenErnst-August-Carree, HannoverDZ Bank, Berlin

Indoor users should not bedazzled. Luminaires shining intothe interior impair the view outof the building. Lighting controlsystems can be used to controlthe light in individual rooms andto create patches of light on thefacade.

Conclusion


Perforated facade

Uplights





Banded facade

Under daylight conditions thestrip of windows appears dark.Illuminating the indoor areas atnight forms a strong contrastbetween dark facade surfaces and

a bright strip of windows. Thelighting on the balustrades aug-ments their horizontal structure.

Observation

Daylight

Uplights, indoor

Band of light

The strong contrast betweenbright indoor lighting and thedark outer surface at night canonly be compensated for to asmall extent with facade wash-lighting.

Conclusion




Applications

Projects:

Greater London Authority, LondonMunicipal works, LüdenscheidE-Werk event halls/SAP SI offices,Berlin


Banded facade





Transparent facade

Under daylight conditions,the transparent facade appearsdark and reflects its surround-ings. Indoor lighting allows theobserver to see into the building.

Ceiling washlights in the indoorarea emphasise the ceiling sur-faces and increase the overallimpression of interior brightnessat night. The facade constructionis silhouetted. Lines of light inthe ceiling area of the individualfloors underline the horizontal

Observation

Daylight

building structure. Uplightsemphasise the vertical elementsof the facade.

Downlights, indoor

Uplights, indoor

Lines of light





Transparent facade

Applications

Projects:Mediathek, SendaiRuhr Festival Theatre CongressCentre, RecklinghausenZürich Insurance, Buenos AiresMaritime Museum, Osaka

The visual perspective from theground makes the lighting effectof the indoor area appear largerwith uplights than with down-lights. Dazzling the users of theindoor area should be avoided.Luminaires shining into theindoor area will impair the view

out of the building.

Conclusion

Uplights, outdoor




Trees Types of trees

In the field of landscaping, treesare the most important elementsfor forming areas. The shape andsize of the trunk and tree crownvary depending on the type of tree. The most well-known treeforms are rounded, columnar,spreading and flat-crowned (e.g.a palm). The winter scene is char-acterised by filigree branches,while in the summer the leaves

of the crown thicken to form avoluminous mass. In addition tothe shape, the appearance of treesis also characterised by blossomand foliage in the course of theseasons.


Vegetation

Clusters of trees

Rows of trees Tree-lined avenue Spacing of trees




Floodlights aimed upwards makethe tree crown appear three-dimensional. Two floodlights fromthe front, yet to the side, illumi-nate the crown evenly as a volu-

minous mass, while floodlightsmounted at the side add greateremphasis to the three-dimension-ality. Floodlights arranged aroundthree sides illuminate the crownevenly from all sides and reducethe three-dimensionality of thetree form. Floodlights in the

ObservationTypes of illumination

Floodlight in front

background create back-lightingand make the tree crown into asilhouette Uplights at the trunkaccentuate the trunk as a linearfeature and visually connect the

crown to the ground. Dependingon the season, light from abovewill either emphasise the contourof the crown or accentuate theshadows of the branch structureon the ground.

Floodlight on the right

Floodlights right and left

Floodlights on three sides

E GuideOutdoor lighting | Lighting applications | Vegetation

Trees




Floodlight behind

Uplight

Spotlight from above


Trees

Luminaires arranged on severalsides give an even illuminationof the tree, while one or twoluminaires create a greater three-dimensional effect. Narrow-beamed uplights are suitable forhighlighting any striking, tall treetrunks. The texture of the bark isbrought out stronger when light-ing from the front. Positioningthe luminaires to the side givesrise to a narrow line of light onthe trunk. When illuminating awall behind a tree, the silhouetteof the crown and trunk becomesapparent. Spotlights mountedin atria or on facades can castthe contour of the tree and/orbranches as a shadow on theground.

Conclusion





Trees

Small tree

Large tree

One or two luminaires accentuatetrees of small dimensions. Sev-eral floodlights produce an evenillumination of large, fully growntrees.

ObservationTree growth

Tree growth and avoiding glareare two points that must beconsidered when arranging andaiming the luminaires. On large

trees, several luminaires may benecessary to achieve an even illu-mination and to avoid a distortedperception of light and dark parts.Flexible, directable luminaireswith ground spikes can be repo-sitioned and re-aimed as the treegrows. Luminaires recessed intothe ground blend into the area

Conclusion of landscape better but requiremore work to reposition however.





Trees

Floodlit illumination of the treecrown particularly brings out thebeauty of the outermost blossomin the springtime. In the summer,the dense foliage makes the crown

appear as a solid mass. Coloured

ObservationSeason

Spring

Summer

Autumn

Winter

Lamp selection is a factor thatinfluences the colour of light andthe colour rendition of the leavesand blossom. Daylight white col-ours of light emphasise blue-greenfoliage colours, whereas warmwhite colours of light accentuatebrownish-red leaves.

Conclusion

leaves are characteristic for theautumn. In the winter, the light-ing effect is reduced to the fili-gree branch work.




Applications

Projects:

Ernst-August-Carree, HannoverERCO, LüdenscheidERCO, LüdenscheidERCO, Lüdenscheid

Lighting for- park and garden complexes- entrance areas- atria

Preferred luminaire groups- spotlights- floodlights- uplights


Trees





Types of trees

Floodlit illumination emphasisesthe shape of the tree crown asa solid volume. Positioning theluminaires close to the tree under-lines with grazing light the texture

of the crown and of the trunk. Theillumination from below bringsout the three-dimensionality of the crown when the foliage isquite open.

Observation

Floodlight, front



Floodlight behind

Tree form: rounded





Floodlight in front




Types of trees

Uplight

Tree form: Weeping




Uplight



Types of trees

Spotlight in front

Spotlight on the right

Floodlight behind

Tree form: columnar





Types of trees

Spotlight behind

Uplight

Floodlight at front


Spotlights on three sides

Tree form: conical




Floodlight behind


Types of trees

Spotlight in front

Spotlight on the right

Spotlights on three sides


Tree form: palm




Rounded, weeping trees withdense, low hanging foliage thatcannot be seen through, lendthemselves to floodlit illumina-tion and the luminaires are bestpositioned outside the area underthe tree. On spreading trees withthin, see-through foliage, illumi-nating from within the area underthe tree, using uplights allowsthe whole tree crown to appear

aglitter. Illuminating a tree withgrazing light requires a flat inci-dent beam at approximately 15degrees. Spherical trees require agreater distance between lumi-naire and crown than columnartrees do here. Narrow-beameduplights are particularly suit-able for lighting high palms.

Conclusion The desired illuminance must beselected to suit the reflectanceof the leaves.

Uplight


Types of trees

Spotlight behind





Clusters of trees

Floodlights located in front illu-minate the tree crowns evenly.Floodlights positioned at thesides produce a hard contrast of light and shadow. Luminaires on

two sides avoid hard shadows.Uplights at the trunk emphasisethe trunk as a vertical linearfeature.

ObservationLuminaires

Floodlight at front

Floodlights at sides

Uplights




The cluster of trees can be visu-ally differentiated by using dif-ferent luminaires and differentlyaimed. Spatial depth is created byadding lighting emphasis in the

foreground, middle ground andbackground. Stronger brightnesscontrasts support this effect. Nar-row-beamed luminaires providehighlighting, while broad-beamedfloodlights take on the task of general lighting.

ObservationLight distribution

Having several luminaires withhigh cut-off angles reduces theglare compared to a few broad-beamed luminaires. Narrow-beamed and well-aimed lumi-naires reduce the superfluousemission of light into the sur-roundings. The decentralised illu-mination of trees allows a differ-entiated lighting of a cluster of trees. Spotlights are suitable for

additional highlights. Tree growthand the avoidance of glare are to

Conclusion be considered when positioningand aiming the luminaires.


Clusters of trees

Projects:ERCO, LüdenscheidERCO, LüdenscheidBank of China, BeijingBank of China, Beijing

Applications Lighting for- park and garden complexes- entrance areas- atria






Rows of trees

Upwardly directed spotlightsemphasise the tree canopy. Flood-lights with asymmetric light distri-bution give homogenous lightfrom base to canopy even on tall

and broad rows of trees. Narrow-beamed uplights highlight thetree trunk as a vertical, linearfeature.

Observation

Tree form: roundedFloodlight

Tree form: columnarSpotlights

Tree form: roundedUplights

Tree form: columnarUplights




Tree form: palmUplights


Rows of trees

The effectiveness of rows of treesto delineate space depends to avery large extent on the type of tree. Thus, depending on the typeof tree, a closely planted row of trees can appear as a ‚wall‘ or a‚colonnade‘. Narrow-beamed andwell-aimed luminaires reduce theglare and the spill light into thesurroundings. The tree growthmust be considered when posi-

tioning and aiming the lumi-naires.

Conclusion

Tree form: palmSpotlights

Applications

Projects:ERCO, LüdenscheidLoher Wäldchen park,Lüdenscheid

Lighting for- park and garden complexes- entrance areas- pathways






Tree-lined avenue

Upwardly directed spotlightsemphasise the tree crowns.Floodlights with asymmetric lightdistribution give homogenouslighting from base to canopy even

on extensive avenues of tall trees.Narrow-beamed uplights high-light the tree trunk as a vertical,linear feature.

Observation

Tree form: roundedFloodlights

Tree form: roundedUplights

Tree form: columnarSpotlight







The spatial profile of tree-linedavenues depends to a very largeextent on the type of tree. Thus,depending on the type of trees, anavenue of narrowly spaced treescan act as a wall and segregate adefinite area or can appear as acolonnade. Narrow-beamed andwell-aimed luminaires reduce theglare and spill light into the sur-roundings. The tree growth mustbe considered when positioningand aiming the luminaires.

Conclusion


Tree-lined avenue





Spacing of trees

Broad, upwardly directed beamsof light emphasise the undersideof the tree canopy. Narrow-beamed uplights highlight thetree trunk as a vertical, linear

feature.

Observation

Tree form: weepingUplights, narrow-beam

Tree form: weepingUplights, wide-beam

Tree form: columnarSpotlights






Spacing of trees



The tree crowns of narrowlyspaced trees combine to take onthe effect of a canopy. Havingseveral narrow-beamed lumi-naires reduces the glare comparedto a few broad-beamed lumi-naires. On pathways and trafficroutes, it must be ensured thatthe luminaires are well shieldedto prevent glare.

Conclusion




E

In this subchapter, applicationpossibilities for outdoor lumi-naires are shown using designexamples. Design variations arepresented using simulations.

Entrance area, small Entrance area, large


Design examples

Historical facade

Pathway




The entrance area is formed bya negative volume, which is setapart from the outdoor area bya few steps.

Situation

E GuideOutdoor lighting | Design examples

Entrance area, small

Planning Design 1The wallwashers integrated inthe ceiling provide a very homoge-nous illumination of the wall. Theluminaires are integrated into thearchitecture.

Design 2The light intensity distributionof the downlights determines theoverall impression of the scene.On the wall, uniform beams of become apparent and becomethe formative element. The mate-rial texture on the back wall isbrought out by the light.

Design 3To meet the functional criteriaof an entrance, it is sufficient toilluminate the ground. The overallvolume of the entrance recedesinto the background.




Design 2To achieve a decorative lightingeffect, the downlights are posi-tioned near to the wall.

Arrangement


Entrance area, small

Design 1The offset of the wallwashersfrom the wall measures half thewall height. The luminaire spac-ing is equal to the offset from

the wall.

Design 3The floor washlights are locatedat a height of 60cm in order toavoid glare.




The design draft shows a repre-sentational entrance area with acanopy roof projecting out a longway. This is supported by evenlyarranged struts. The main task is

to reinforce the representationalcharacter using the lighting.

Situation


Entrance area, large

Planning Design 1Downlights follow the form of thecantilever roof along the struts.The circles of light made by thebeams on the floor emphasise thedynamics of the circular facade.The wall adjoining onto the glassfacade is delicately brightened byrecessed ceiling wallwashers.

Design 2Light is projected onto the canti-lever roof via ceiling washlights.The roof reflects the light ontothe floor. The indirect lightingcasts evenly diffused light ontothe ground. Additional illumina-tion of the wall can be dispensedwith since the wall is also givensufficient light by the reflectionfrom the roof. The luminairesappear as independent architec-tural elements.

Design 3Each strut is highlighted by foursurface-mounted downlights. Thephysical makeup of the struts isemphasised.




Design 2The ceiling washlights aremounted at two thirds of thestrut height.

Arrangement


Entrance area, large

The arrangement of the narrow-beam recessed downlights fol-lows the circular course of theroof edge. To achieve a relationbetween wall and luminaires, the

offset of recessed ceiling wall-washers from the wall measuresonly a quarter of the wall height.

Design 3The offset of the recessed ceilingwallwashers from the wall meas-ures a quarter of the wall height.The surface-mounted downlightsare placed in a circular arrange-ment around the struts at a shortdistance away.




Historical facades require light-ing concepts that are in harmonywith the architectural features.For classical facades, the follow-ing features are to be given con-

sideration in the lighting concept:- columns- porticoes- friezes- facade division into three areas:portal and two side wings

In all the examples listed a faintgeneral lighting of the facade isensured via lens wallwashers. Thelighting should not be incidenttoo steeply, since otherwise irri-tating heavy shadows could becast in the area of the friezes.

Situation


Historical facade

Planning Design 1The columns are silhouettedagainst the entrance area, whichis illuminated by surface-mount-ed downlights. The three-dimen-sional impression of the porticois greatly reduced by the columnsthat now appear almost flat. Thefront elevation of the building isclearly divided into three becauseof the emphasis given to the

facade‘s central section.

Design 2The columns are illuminated withnarrow-beam uplights. The tym-panum is illuminated separately.The fact that the entrance areais set forward from the facadebecomes much more pronounced.The view is attracted to the cen-tral section of the building.

Design 3The facade is clearly given a hori-zontal division by illuminating thefrieze. The overall breadth of thefacade becomes more significant.The columns were illuminatedas in design 2, but with reducedlight intensity so as not to overlyemphasise the entrance. Overall,this differentiated lighting con-cept lends the historical facadea most magnificent character.




Design 2The columns are emphasised bynarrow-beam uplights arrangedcircularly around the columns.

Arrangement


Historical facade

The starting point of all threedesign examples is the homoge-nous general lighting of thefacade with lens wallwashersmounted as recessed floor lumi-

naires. These are arranged in aline at a distance of one thirdof the building height in frontof the right and left sections of the facade.

Design 3Directional luminaires for high-lighting the frieze are located ata distance of one tenth of thewall height in front of the twoside sections of the facade. Thespacing between the directionalluminaires themselves is relativelysmall so that an even illuminationof the frieze is obtained. Narrow-beam uplights in the semicirclearound the four columns add

brightness.

Design 1One surface-mounted downlightwith a wide light intensity distri-bution is positioned behind eachand every column.




Orientation along pathways canbe provided either by primarylighting of the path surface orby emphasising certain referencepoints in the area.

Situation


Pathway

Planning Design 1Orientation is provided here onthe one hand by linearly arrangedpoints of light from floor wash-lights and on the other by mark-ing points of interest. In thisexample, a low illumination of the pathway by floor washlightsis sufficient because illuminatingthe row of trees provides orien-tation.

Design 2The path surface is well lit withwide-beam floor washlights. Theevenly arranged floor washlightsguide one‘s view. The adjacenttrees are silhouetted against theevenly illuminated wall behindthem. The spatial limits areemphasised and this gives theviewer an indication about thevolume of the area.




Design 2The lens wallwashers for illumi-nating the wall are recessed inthe floor at an offset from thewall of a third of the wall height.

Arrangement Design 1The uplights are arranged to theright and left of the trees. A rowof floor washlights runs parallelto this.


Pathway




E GuideOutdoor lighting

Lighting design

The development in architecturetowards transparency transformsbuildings at night into effigiesshining from the inside out.Light has advanced to become amarketing topic for a number of cities. A sensitive treatment of light in the outdoor area is crucialfor acheiving a clear view of thenight sky.

Dark Sky




Dark Sky stands for a lightingdesign in the outdoor area where-by the lighting concentrates onwhat is actually essential. Anykind of light pollution is avoided

and observation of the night skyis enabled. This approach com-bines a lasting design conceptwith a luminaire technologytailored to suit. The cooperativeteamwork of lighting designers,architects, landscape gardeners,building sponsors, electrical fit-ters and luminaire manufacturersforms the basis for a successfulimplementation of the Dark Skyconcept.

Introduction

E GuideOutdoor lighting | Lighting design

Dark Sky

Light pollution The term ”light pollution” refersto that spill light which, due toits illuminance, its direction or itsspectrum, causes interference inthe context in question. Spill lightand glare reduce the visual com-fort and the desired content of information cannot be conveyed.The ecological consequencesinclude the waste of energy andthe negative effects on flora and

fauna.

Graphic: Artificial Night SkyBrightness in Europe

Credit: P. Cinzano, F. Falchi (Uni-versity of Padova), C. D. Elvidge(NOAA National Geophysical DataCenter, Boulder). Copyright RoyalAstronomical Society. Reproducedfrom the Monthly Notices of theRAS by permission of BlackwellScience.www.lightpollution.it/d msp/




Luminaires Luminaires suitable for Dark Skyapplications feature precise lightcontrol and a defined cut-off foroptimum visual comfort. Havingno emission of light above the

horizontal plane is a decisive cri-terium for open area and pathwayluminaires. A low luminance atthe light aperture avoids exces-sive contrasts in luminance levelsin the outdoor area.

E GuideOutdoor lighting | Lighting design

Dark Sky

Planning

Arrangement

The first design task for a Dark

Sky concept is to ascertain forwhat purpose and with whatquality the particular areas areto be illuminated. The followingis decisive for a lasting lightingconcept:- adequate illuminance- avoidance of spill light abovethe horizontal plane- correct alignment of luminaires- reduce or switch off the lightingwhen no longer needed

The luminaires should be arrangedsuch that the elements to be illu-minated are optimally lit and nolight shines past the objects. Thisavoids dazzling the observers.

PlanningControl

With the Dark Sky concept thelighting control takes on specialsignificance for regulating theintensity and duration of thelighting for individual zones,thus regulating the overall lightemission. The lighting controlallows switching and dimming forindividual areas. Predefined lightscenes can be recalled dependenton the time of day and seasonvia time sensors and motion sen-sors. Function-dependent lightingscenes for the twilight, eveningand night can be controlleddependent on sensors.



278

,IGHTINGCONTROLS-ODULE

,UMINAIRES


"UILDING

-ANAGEMENT

3YSTEM

$!,)

$-8

"!#NET

,/.

+.8

%THERNET


E GuideLighting control

Lighting control not only enablesthe lighting to be adjusted to suitthe visual requirements but alsoallows it to shape and interpretthe architecture. Light scenes areeasily set up using the appropri-ate software and can be recalledvia an interface. The inclusion of light colours and the time dimen-sion opens up a room for sceno-graphic lighting with dynamic

effects. Lighting control systemswith sensors or time programsalso help adjust the power con-sumption in a room to its usageand thus optimise the economicefficiency of a lighting system.

Controlling the light DevicesControl systems

Design examples




The atmosphere in a room can bechanged by controlling a numberof variables. These include basicfunctions such as switchingcircuits on and off through toautomatically timed colour pro-gressions. Programming the lightscenes means that the settingsare saved but can be redefinedand adjusted to suit changingrequirements.


Controlling the light

Functions




E GuideLighting control | Controlling the light

Functions

Switching and dimming are twobasic functions of a lightingcontrol system that can be usedto produce different lightingsituations. Luminaires with vari-able light colours also include acolour setting mode. Featuressuch as cross-fading and dynamiccolour progression are crucial fordynamic lighting designs. Light-ing changes can be initiated and

regulated automatically via timeand sensor control.

Switching Light colourDimming

Scene Dynamic colourprogression

Cross-Fading

Sequence SensorTimer




E GuideLighting control | Controlling the light | Functions

Switching

The easiest situation is to turnthe light on and off with a switchor a push-button. For a variety of light scenes different circuits withseparate switches are required.

Suitably positioned switchesresult in easier usage. Most lampsproduce full light output imme-diately. High-pressure dischargelamps, however, usually have arun-up time of several minutesand an even longer cooling-downperiod before re-ignition.





Dimming

Dimming is the infinitely variableadjustment of the light outputof a light source. It enables thecreation of different light scenes,increases the visual comfort and

optimises the power consump-tion. Dimming also prolongsthe life of incandescent lamps.Thermal radiators such as tung-sten halogen lamps are easilydimmed. Fluorescent lamps andLEDs require special dimmablecontrol gear.





Light colour

The light colour of luminaireswith variable colours of lightcan be defined by hue, satura-tion and brightness. The possiblecolours depend on the lamp and

the lighting technology used.Coloured light can change theatmosphere of a room and high-light individual objects. RGB col-our mixing technology controlsthe individual primary coloursred, green and blue to producethe required light colour.





Scene

A scene is a static lighting situ-ation. It defines the state of alllighting components such asluminaires, light ceilings and lightobjects with their different switch

and dimmer settings. The scenescan be saved in lighting controlsystems. The user can presetcomplex luminaire settings andconveniently recall them eithermanually or automatically.





Cross-Fading

In regard to lighting, cross-fading refers to the transitionfrom one light scene to another.The cross-fading time is theperiod required for the scene

change. It varies between instantchange and a transition of severalhours. High-contrast scenes witha short cross-fading time gener-ate considerable attention. Subtletransitions with lengthy cross-fading times, on the other hand,are hardly noticeable. The scenechange can be initiated by theuser, a sensor, or a t imer.





Dynamic colour progression

Dynamic colour progressionrefers to the chronology of colourchanges. Within a defined totalrunning time, specific colours aretriggered at specified times. There

are different options available torepeat this progression, includinginfinite loop and “forward andback“.





Sequence

A sequence refers to a progressionof successive light scenes. Thedefinition of a sequence requiresboth individual scenes and infor-mation on their transition. A

sequence can automatically berepeated once completed or,alternatively, end.





Timer

A timer allows light scenes to berecalled at predefined times. Timeand calendar functions providegreat flexibility for the automa-tion of scenographic lighting.

Specified start and end times,for example, set the lighting tospecific shop-opening times orlicensing hours.





Sensor

Sensors monitor propertiessuch as brightness or motionand allow an automatic adjust-ment of the lighting to changingambient conditions. A brightness

sensor can be used for daylight-dependent lighting control.Motion sensors register move-ment in the room and controlthe light depending on activityto reduce power consumption.



290


,UMINAIRES


"UILDING

-ANAGEMENT

3YSTEM

$!,)

$-8

"!#NET

,/.

+.8

%THERNET



Control systems

Buildings increasingly useautomatic control systems. Thelighting is only one component,operation of solar screen equip-ment, air-conditioning and secu-rity systems are others. Speciallighting control systems havethe advantage that they can bedesigned to suit the requirementsof a lighting design and are lesscomplex than more extensive

building control systems.

Lighting controlsystems

Programming thelighting

General controlsystems



291

#OMPLEXITY

0RICE,IGHTINGCONTROLSYSTEMS

%)",/.

$!,)

$-8

6

,UMINAIRE

/THERLUMINAIRES

0OTENTIOMETER

OREXTERN

CONTROLSYSTEM

3WITCH

2ELAYCONTACT

.EUTRALCONDUCTOR#IRCUIT

%#'66

,UMINAIRE

/THERLUMINAIRES$!,)#ONTROLLER


4RANSFORMER%#'$IMMER!CTUATOR

3WITCH2ELAYCONTACT

$!,),INE

,UMINAIRE

/THERLUMINAIRES$-8#ONSOLE


$-8$IMMER

3WITCH2ELAYCONTACT

$-8LINE

4ERMINATOR


E GuideLighting control | Control systems

Lighting control systems

Lighting control systems switchand dim luminaires, set up lightscenes and manage them in spaceand time. The decision to selecta specific system depends on thesize of the lighting system, therequirements in regard to con-trollability, user-friendlinessand economic considerations.Digital systems that allow lumi-naires to be addressed individu-ally provide great flexibility. Theiruser-friendly features includeeasy programming and operationalong with a simple installationprocess. Lighting control systemscan be integrated as a subsysteminto a building managementsystem.

1V-10V DALIDMX



292

,UMINAIRE

/THERLUMINAIRES

0OTENTIOMETER

OREXTERN

CONTROLSYSTEM

3WITCH

2ELAYCONTACT


%#'

66

,UMINAIRE

/THERLUMINAIRES$-8#ONSOLE


$-8$IMMER

3WITCH2ELAYCONTACT

$-8LINE

4ERMINATOR

,UMINAIRE

/THERLUMINAIRES$!,)#ONTROLLER


4RANSFORMER%#'$IMMER!CTUATOR

3WITCH2ELAYCONTACT

$!,),INE


E GuideLighting control | Control systems | Lighting control systems

1V-10V Electronic Control Gear (ECG) iscontrolled by analogue 1V-10V signals. This technology is widelyused in low-complexity lighting

systems. The dimmer setting istransmitted via a separate controlline. The control gear regulatesthe output of light from theluminaire. Since this type of ECGcannot be addressed, the controlcircuit for the control line mustbe carefully planned, because itsallocation cannot be changed.The grouping of the luminairesis determined by the circuits inthe electrical installation. Anychange of use requires a newarrangement of the connectionand control lines. Feedback on

DMX

The DMX (Digital Multiplexed)digital control protocol is pre-dominantly used for stage light-ing. In architectural lighting, thisprotocol is used for features suchas media facades or stage-likeroom lighting effects. The datais transmitted via a dedicated5-core cable at a transfer rate of 250 Kbits/s which can control upto 512 channels. Each luminairemust have a bus address. Whenusing multi-channel devices withcolour control and other adjust-able features, each functionrequires a separate address. For along time, the data transfer wasunidirectional and only enabledthe control of devices. It did not

provide feedback on aspects such

as lamp failure. The DMX 512-Aversion now allows for bidirec-tional communication.

DALIDigital Addressable LightingInterface (DALI) is a control pro-tocol that makes it possible tocontrol luminaires which haveDALI control gear individually. Thesystem allows user-friendly lightmanagement in architecture andcan be integrated as a subsysteminto modern building control sys-tems. The two-wire control linewith a transfer rate of 1.2 Kbits/scan be run together with themains supply cable in a 5-corecable. The bidirectional systemallows feedback from the lumi-naires on different aspects suchas lamp failure. The DALI protocollimits the number of devices to64. The standard version storesthe settings for a maximum of 16 luminaire groups and 16 lightscenes within the control gear.General information on DALI:www.dali-ag.orgThe ERCO Light System DALI,saves settings in a centralcontroller with a greater stor-age capacity. This allows moreluminaire groups, light scenes and

fading times along with the cod-ing of the control gear memoryfor other features. The systemis compatible with other DALIdevices. Light System DALI can

provide both economical lightmanagement and scenographiclighting.

lamp failure, etc., is not possiblewith the 1V-10V technology.



293

&LOORSOR

"UILDING0ARTS

3INGLE2OOMS

"-3

6 6

$ - 8

$ ! , )

+ . 8

, / .

,UMINAIRE

/THERLUMINAIRES

!CTUATOR66

3WITCH2ELAYCONTACT


%#'66

"US

,UMINAIRE

/THERLUMINAIRES

$!#ONVERTER


%#'66

"US

3WITCH2ELAYCONTACT


E

Building management systemsare used to control differentbuilding systems such as theheating, solar screening equip-ment, and the lighting. Theyare more complex than systemsthat solely control the lightingand thus are more involved interms of planning, installationand operation. An establishedprotocol ensures communica-tion between the systems overa flexible network. The controlsystems form the basis for build-ing automation, to simplify andautomate the different func-tions in a building. The buildingautomation is divided into threelevels: the management levelfor user-friendly visualisation,the automation level for dataexchange, and the local level withsensors and actuators. There areno integrated receiving devicesin the luminaires (interfaces) fordecoding control signals; lightingcontrol is achieved by wiring indi-vidual circuits.

KNX LON

GuideLighting control | Control systems

General control systems



294

,UMINAIRE

/THERLUMINAIRES

!CTUATOR66

3WITCH2ELAYCONTACT


%#'66

"US

,UMINAIRE

/THERLUMINAIRES

$!#ONVERTER


%#'66

"US

3WITCH2ELAYCONTACT


E GuideLighting control | Control systems | General control systems

KNXKonnex (KNX), known throughthe European Installation Bus(EIB), is a standardised digitalcontrol system which controls

not only the lighting but alsoother systems such as heating,ventilation and solar screeningequipment. KNX is suitable as anetwork of electronic installa-tions for building automation.Remote monitoring and controlmake it easy to use. The data istransmitted over a separate 24V control line-twisted pair wire ata rate of 9.6 Kbits/s. The decen-tralised communication is bidi-rectional so that the receiver canalso provide feedback. Each busdevice can transmit independ-

ently. An allocation of prioritiesensures proper communicationand prevents data collisions. Dueto the individual addresses of thesensors and actuators, this alloca-

tion is flexible and can easily bechanged. KNX is used in domesticbuildings and in large installa-tions such as offices or airports.

LON

Local Operating Network (LON) isa standardised digital control pro-tocol which controls building sys-tems and is also used in industrialand process automation. Via TCP/IP, LON networks can be combinedto form cross-region networks andbe remote-controlled. LON is basedon intelligent sensors and actua-tors. The microprocessor of eachLON node, called a ”neuron”, canbe programmed and configured.The data transfer for up to 32,000nodes is over a twisted pair wire,as a separate control line, at a rateof up to 1.25 Mbit/s.




E

Lighting systems can be pro-grammed with software to pro-vide great flexibility and allow anadjustment of the lighting to indi-vidual requirements. This resultsin complex lighting systems withsensors and interfaces that oftenrequire professional installationand maintenance. Users requiresimple day-to-day operation thatallows them to make changes

themselves.Non-standard systems can includea great deal of complexity to caterfor special building requirements.Problems or changes, however,may require the support of a pro-fessional programmer. So, stand-ardised lighting systems thatallow certain parameters to bechanged are easier to operate andenable lighting designers or usersto make the necessary changes.The decision on the type of light-ing control system and softwaredepends on technical aspects suchas the size of the lighting system,its integration with AV technologyor building control systems, andthe complexity of the installation.Further criteria for the user to

GuideLighting control | Control systems

Programming the lighting

consider are ergonomics, flexi-bility, and maintenance. A simpleinstallation process, rapid famil-iarisation and easy to use soft-ware aid setup and operation.




E

Lighting control systems are com-posed of different components:sensors register changes in thesurroundings, control panelsenable light scenes to be recalledor new lighting parameters to beprogrammed. The output devicestranslate the control circuit sig-nals into actions. The connectionto the computer allows for easyoperation of the lighting control

system through software, whilegateways facilitate the combina-tion of different control systems.

GuideLighting control

Devices

Sensors Output devicesControl panels

Interfaces Software




E

Sensors are measuring devicesthat register ambient conditionssuch as brightness or motion.The lighting is adjusted when thelighting control system receivesan impulse or a value above orbelow a predetermined level.

GuideLighting control | Devices

Sensors

Light sensor Motion sensor




E GuideLighting control | Devices | Sensors

A light sensor monitors lightlevels and enables the automaticcontrol of light scenes depend-ing on available daylight. Usinga lighting system in combination

with changing daylight levels inrooms ensures a controlled illumi-nance, which is useful, for exam-ple, in order to maintain mini-mum values for workplaces or toreduce the radiation exposure onexhibits in museums. A daylightsensor on the roof (external sen-sor) measures the illuminanceof the daylight and controls thelighting inside. If the light sensoris in the room (internal sensor),it measures the total illuminanceof the incident daylight and thelighting in the room in order to

Light sensor

Motion sensors register movement

in the room and can be used, forexample, in vacant offices to dimor switch off the light automati-cally in order to save power. Inmuseums, the lighting on sensi-tive exhibits can be reduced whenthere are no visitors. Installed out-doors, motion sensors can reducepower consumption at night aslighting is switched on only whenand where required. The switchingthresholds must be set to suit thesituation.

Motion sensor

control the light level dependingon the daylight. The first processis referred to as open loop con-trol, the second as closed loopcontrol.

In combination with scene con-trol, light scenes can be control-led depending on the daylight,for example, by using a twilightswitch. In the same manner, thesensor control can be used tooperate solar screening equip-ment.




E

Simple applications only require apush-button to operate the light-ing control system. Control panelswith displays are recommendedfor sophisticated applications andcan also be used to program thelighting system. A remote controldevice allows light scenes to berecalled from anywhere in theroom.


Control panels

Push-button Switch Remote control

GUI




E GuideLighting control | Devices | Control panels

A push-button closes or opensa circuit to switch a luminairegroup or light scene on or off. Touse different functions, a systemrequires several push-buttons.

The functions are determinedwhen the lighting control systemis installed.

Push-button

A switch opens and closes a cir-

cuit. It locks into position anddoes not require continuouspressing as does a push-button.A light switch controls the light-ing by switching it on or off.

Switch

A remote control is used to con-trol the light separately fromwall-mounted control panels.In conference rooms, a remotecontrol is a convenient device torecall different light scenes fromanywhere in the room. An infra-red remote control requires an IRreceiver to recall any functions.

Remote control

Graphical User Interface (GUI) isthe familiar way of interactionwith software on computers orcontrol panels based on graphicalimages. Simple user interfacesprevent users having to learncomplex command languagesand simplify the operation. A GUIcan be combined with a touch

screen so that interaction takesplace directly on the screen.

GUI




E

Output devices are actuators orcontrollers that translate thesignals in a control circuit intoan action. Actuators (e.g. relays)or dimmers operate or controlthe light output through voltagechanges. Controllers have theirown processors and send signalsto the control gear.


Output devices

Relay Dimmer Controller




E GuideLighting control | Devices | Output devices

A relay is a switch that is acti-vated by electric current. Whenoperating metal halide lamps, arun-up time of several minutesand a longer cooling-down phase

before re-ignition must be takeninto account.

Relay

The dimmer is used for the infi-

nitely variable regulation of theoutput from a light source. Lead-ing edge control is applied toincandescent lamps. Low-voltagehalogen lamps with electronictransformer are dimmed usingtrailing edge technology. Ther-mal radiators such as tungstenhalogen lamps are easy to dim.Fluorescent lamps require spe-cial control gear, while compactfluorescent lamps require specialelectronic control gear units.Conventional compact fluores-cent lamps cannot be dimmed.LEDs can easily be dimmed withthe appropriate control gear.In analogue 1V-10V technology,dimming is possible by using aspecial ECG with input for the1V-10V control voltage anda potentiometer or a controlsystem supplying analogue 1V-10V control voltage, such as the

Dimmer

Controllers are electronic unitsfor process control. A lightingcontrol system such as the LightSystem DALI saves light scenesand controls the luminaires.The amount of data which canbe used to store the settings islimited by the storage capacityof the controller. The user oper-ates the controller via softwareor a control panel. A control lineestablishes a connection to theluminaires and transmits the sig-nals to the control gear.In a LON system, D/A modulesare used to save and recall lightscenes. As output devices, theyallow the connection of externaldimmers or direct control of dim-mable ECGs or transformers.

Controller

ERCO Area Net or KNX actuators.

The dimmers are often installedin switch cabinets. The controllines are permanently connectedto luminaires or groups of lumi-naires. The digital control pro-tocol, DALI, on the other hand,allows for the individual controlof the dimmable ECGs for all theconnected luminaires.




E GuideLighting control | Devices

Interfaces or ‚Gateways‘ enablethe exchange of signals and databetween different data networksor bus systems. Where severalcontrol systems are used in a

building, the data needs to betransferred between these sys-tems. Lighting control systemscan be integrated as subsystemsinto a building management sys-tem by means of a gateway. Inthe same manner, gateways canbe used, for example, for DALIlighting control systems to acti-vate 1V-10V controllers for thesun screening equipment.

Lighting control software turnsany PC connected to a lightingcontrol system into a controlpanel and programming devicefor the lighting system. The PCcan be connected to the lightingcontrol system using interfac-ing standards such as USB. Thebrightness and light coloursettings are combined in lightscenes. The light scenes are pro-

grammed using the softwareand recalled via control panels.The software can provide manyadditional functions, such asspatial and timed control. Atimer program ensures lightingcontrol according to predefinedsequences or calendar settings.With sequential control, the lightscenes are repeated in cycles.The calendar function recalls thelight scenes according to prede-termined times or days. The DALIsystem with individually address-able luminaires allows flexibleallocations and regrouping.The firmware is the softwarerequired for the operation of devices and is saved in a flashmemory. The PC software is usedto operate the lighting controlsystem on the computer and issaved on the hard drive.

Interfaces

Software




E

The application area for a lightingcontrol consists of the functionaladaptation of the individual light-ing requirement, the optimisationof the use of energy and the dif-ferentiated design of architecture,exhibition and presentation.

GuideLighting control

Design examples

Museum Office Showroom

Restaurant Multifunctional room




E GuideLighting control | Design examples

Museum

Room of museum for presenta-tion of paintings and sculptures.Requirements: The illuminancelevel is kept low as long as novisitors are in the room. When

someone enters the room theoptimum exhibition lighting isswitched on.

Observation





Museum

Planning





Office

Requirements: Several illumi-nance levels can be set; they arecontrolled dependent on thedaylight.It is operated via push-buttons

on the door. A maximum of fourdifferent lighting levels can beselected via the push-buttons.The light scenes are defined fordifferent uses according to theilluminances. The actual regula-tion to the set value within thelight scene is performed via thedaylight regulation.

Observation





Office

Observation




Planning


Office





Showroom

Observation Requirements: The lighting pro-gram is made up of differentiatedlight scenes. It is operated via aPreset at the reception. A daylightcontrol optimises the power con-

sumption.





Showroom

Observation

Planning





Restaurant

Observation Requirement: different lightscenes can be recalled at break-fast, lunch and dinner times.





Restaurant

Observation





Restaurant

Planning





Multifunctional room

Observation

Large room

Requirement: Various light scenesfor different purposes with differ-ent room allocation:- training/seminar, large room- meeting, large room

- training, small room






Observation

Large room

Planning




Observation

Small room






The spectrum of lighting tech-nology covers information onphotometric values, light sourcesand luminaire technology. Thesecontents aid orientation so thatan appropriate technical solutioncan be found for the lighting taskin question.Dimensions, units

E GuideLighting technology

Lamps Luminaire technology



319

1 80604020

LED

A

QT(12V)

QT, QPAR

TC

T

HIT

HST

661

L

I Ap

LED

A

QT(12V)

QT, QPAR

TC

T

HIT

HST

180604020



Dimensions, units

Light plays a central role in thedesign of a visual environment.The architecture, people andobjects are all made visible bythe lighting. Light influences ourwell-being, the aesthetic effectand the mood of a room or area.

Luminous flux Light intensityLuminous efficacy

Illuminance LuminanceExposure

Colour of light Colour rendition



320

O

6 6 6

1

6 6 6 1

6 6 6 1

6 6 6 1

6 6 6 1

6 6 6 1

6661

h(lm/W)10080604020

LED

A

QT (12V)QT, QPAR

TC

T

HIT

HST


Luminous flux describes thetotal light power emitted by alight source. As a rule, this radi-ant power could be expressedas emitted energy in the unit of

watts. However, this method isinadequate for describing theoptical effect of a light source,since the emitted radiation isrecorded without discriminationover the entire frequency rangeand the different spectral sensi-tivity of the eye is not considered.The inclusion of the spectral sen-sitivity of the eye results in thequantity termed lumen. A radiantflux of 1W emitted at the maxi-mum extent of spectral opticalsensitivity (photopic, 555 nm)gives a luminous flux of 683 lm.Conversely, the same radiant fluxemitted at frequency ranges of

lower sensitivity as per the V (l)results in correspondingly smallerluminous fluxes.

Luminous flux

E GuideLighting technology | Dimensions, units

Luminous flux, luminous efficacy

The luminous flux F is a measurefor the amount of light of a lightsource.

F = lumen (lm)

The luminous efficacy describesthe efficacy of a lamp. It isexpressed as the ratio of theemitted luminous flux in lumenand the power used in watts. Thetheoretically attainable maximumvalue assuming complete conver-sion of energy at 555 nm wouldbe 683 lm/W. The luminous effica-cies that can actually be attainedvary depending on the lamp, butalways remain far below this idealvalue.

Luminous efficacy

h = F / P

h = lm / W



321

')

#ª

#ª

ª

)

ª


DefinitionAn ideal, point light source radi-ates its luminous flux evenly inall directions in the room, with itslight intensity being equal in all

directions. In practice, however,there is always an uneven spatialdistribution of luminous flux,partly due to the lamp designand partly due to the manner inwhich the luminaire is formed.The Candela, as the unit of lightintensity, is the basic unit of lighting engineering from whichall other lighting engineeringvalues are derived.

Light intensity


Light intensity

The light intensity I is a measurefor the luminous flux F emittedper solid angle O

I = F / O[I]=lm / srlm / sr = Candela [cd]

RepresentationThe spatial distribution of thelight intensity of a light sourceresults in a three-dimensionalbody of light intensity distribu-tion. A section through this lightintensity body will give the lightintensity distribution curve, whichdescribes the light intensity dis-tribution in one plane. The lightintensity is, usually displayed in

a polar co-ordinate system as afunction of the emission angle.To enable direct comparison of the light intensity distribution of different light sources, the valuesare expressed in relation to 1000lmluminous flux. With rotationallysymmetrical luminaires, a singlelight intensity distribution curveis sufficient to describe the lumi-naire. Axially symmetrical lumi-naires need two curves, although,these can usually be representedon one diagram.

Rotationally symmetrical lightsources

Light intensity distribution of a rotationally symmetricallyemitting light source. A sectionthrough this light intensity distri-bution form in the C-plane givesthe light intensity distributioncurve.



322

#ª

#ª

ª

)

ª

ª ª

ª

ª

ª

ª

ª

)g

)g

'

A

B

9

ª ª ª ª ª

)g

)g

'

AA B

9


Axially symmetrical luminaire


Light intensity

Light intensity distribution formand light intensity distributioncurves (planes C 0/180° andC 90/270°) of an axially sym-metrically luminaire.

Emission angle

A light intensity distributioncurve scaled to 1000 lm, shownin polar coordinates. The angularrange within which the maximumlight intensity l‘ decreases to l‘/2denotes the emission angle β. Thecut-off angle α brings the limitemission angle YG to 90°.



323

% !

%H % V

%M

!

)

%P

A


The illuminance is a measure forthe luminous flux density on asurface. It is defined as the ratioof the luminous flux incident on asurface to the size of that surface.

The illuminance is not tied to areal surface, it can be determinedanywhere in the room. The illu-minance can be derived from thelight intensity. Whereby, the illu-minance reduces by the square of the distance from the light source(inverse square law).

Illuminance


Illuminance

Illuminance E as dimension forthe luminous flux per surfacearea unit A

Horizontal illuminance Eh and

vertical illuminance Ev in indoorareas.

The average horizontal illumi-nance Em is calculated from theF luminous flux, incident on thesurface in question A.

Em = F

A

The illuminance at a given pointEp is calculated from the lightintensity l and the distance abetween the light source and thesaid point.

Ep = I a2

[Ep] = lx

[I] = cd

[a] = m

Horizontal illuminance

Average horizontal illuminance

Illuminance at a point



324

,

) !P

%H % V

*

*

,

,


Exposure is described as theproduct of the illuminance andthe exposure time through whicha surface is illuminated. Exposureis an important issue, for example,

regarding the calculation of lightexposure on exhibits in museums.

Exposure


Exposure, luminance

Whereas illuminance expresses

the luminous power incident on asurface, the luminance describesthe light given off by this surface.This light can be given off by thesurface itself (e.g. when consid-ering luminance of lamps andluminaires). Luminance is definedas the ratio of light intensity andthe area projected perpendicu-larly to the emission direction.The light can also be reflected ortransmitted by the surface how-ever. For diffuse reflecting (matt)and diffuse transmitting (murky)materials, the luminance can becalculated from the illuminanceand the reflectance or transmit-tance . Brightness correlates withluminance; although, the actualimpression of brightness is stillinfluenced by how well the eyeshave adapted, by the surroundingcontrast levels and by the infor-mation content of the viewedsurface.

The luminance L of a luminoussurface is given by the ratio of light intensity I and its projectedarea Ap.

L = I / Ap

[L] = cd / qm

Luminance

The luminance of a diffuselyreflecting illuminated surface isproportional to the illuminanceand the reflectance of the surface.

L1 = Eh . R1 / pL2 = Ev . R2 / p

[L] = cd / qm

[E] = lx



325

+

+

3PECTRALCOLOURLOCI

NW

X

Y

TW

WW

++

n

%

!

$

3PECTRALCOLOURLOCI

X

Y


Light colour is the colour of thelight emitted by a lamp. Lightcolour can be expressed usingx,y coordinates as chromaticitycoordinates in a standard colori-

metric system, or, for white lightcolours, it can also be given as thecolour temperature TF. In the CIEstandard colorimetric system, thecolour of light is calculated fromthe spectral constitution andrepresented in a continuous, two-dimensional diagram. The hue isdefined via the chromaticity co-ordinates of the spectral colourand via the saturation level. Thedesign of the diagram features acoloured area that contains everypossible real colour. The colouredarea is encompassed by a curveon which the chromaticity loca-tions of the completely saturated

spectral colours lie. At the centreof the area is the point of leastsaturation, which is designatedas a white or uncoloured point.All levels of saturation of onecolour can now be found on thestraight lines between the uncol-oured point and the chromaticitylocation in question. Similarly,all mixtures of two colours arelikewise to be found on a straightline between the two chromatic-ity locations in question.

CIE-system


Colour of light

Closest colour temperaturePlanck‘s curve contains the chro-maticity locations of Planck‘sradiation of all temperatures.Since the chromaticity locationof a light source often lies near tothe curve, starting from the curveof Planck‘s radiator, a host of straight lines of the closest colourtemperatures is added. With theirhelp, even those light coloursthat are not on this line can beidentified by the closest colourtemperature. On temperatureradiators, the closest colour tem-perature corresponds to some-thing approaching the actualtemperature of the lamp filament.On discharge lamps, the closestcolour temperature is stated.

Planck‘s curve with the hostof linesSection from the coloured areawith Planck‘s curve and the hostof lines of chromaticity loca-tions of the same (closest) colourtemperature between 1600 and10000K. The ranges of the lightcolours warm white (ww), neutralwhite (nw) and daylight white(dw) are shown.

Planck‘s curve with typicallight sourcesSection from the coloured areawith Planck‘s curve and the chro-maticity locations of the standardtypes of light A (incandescentlamp light) and D 65 (daylight) aswell as the chromaticity locationsof typical light sources: candleflame (1), incandescent lamp (2),tungsten halogen lamp (3), fluo-rescent lamps ww (4), nw (5) anddw (6).



326

Light source T (K)

Candle 1900–1950Carbon filament lamp 2100Incandescent lamp 2700–2900Fluorescent lamps 2800–7500

Moonlight 4100Sunlight 5 000–6 000Daylight 5800–6 500(sunshine, blue sky)

Overcast sky 6400–6 900Clear blue sky 10 000–26000

0,500,400,30

0,26

0,34

0,42

x

y

dw

ww4000 k

5000 k

nw

0,500,400,30

0,26

0,34

0,42

x

y

dw

ww4000 k

5000 k

nw

0,500,400,30

0,26

0,34

0,42

x

y

dw

ww4000 k

5000 k

nw


In addition, white colours of light are divided into three maingroups: the warm white range(ww) with the closest colourtemperatures below 4000K, the

neutral white range (nw) between4000 and 5000K and the daylightwhite range (dw) with the closestcolour temperatures over 5000K.The same colours of light mayhave different spectral distribu-tions and a correspondingly dif-ferent colour rendition.

Main groups colourtemperatures


Colour of light

Warm white

Closest colour temperature Ttypical light sources

Neutral white

Daylight white



327

LED

A

QT (12V)

QT, QPAR

TC

T

HIT

HSTRa10080604020


Colour rendition refers to thequality of the reproduction of colours under a given illumina-tion. The degree of colour distor-tion is indicated using the colour

rendition index Ra and/or thecolour rendition grading system.A comparative light source withcontinuous spectrum serves as areference light source, whetherthis be a temperature radiator of comparable colour temperatureor the daylight.

Colour rendition


Colour rendition

To enable the colour rendition of a light source to be determined,the chromatic effects of a scale of eight body colours viewed underthe type of illumination beingscrutinised and also under thereference illumination are calcu-lated and related to each other.The resulting quality of colourrendition is expressed in colourrendition indices; these can relateboth to the general colour rendi-tion (Ra) as an average value orto the rendition of individual col-ours. The maximum index of 100signifies ideal colour rendition asexperienced with incandescentlamp light or daylight. Lowervalues refer to a correspondinglyworse colour rendition. Linearspectra of light lead to good col-our rendition. Linear spectra ingeneral lead to a worse rendition.Multiline spectra are composedof several different linear spectraand improve the colour rendition.

Colour rendition index

Ranges of the colour renditionindex Ra for different lamp types





Lamps

Having technical knowledgeabout lamps will help to makethe right selection with regardsto brilliance, colour rendition,modelling ability and energyefficiency. The spectrum rangesfrom thermal radiators throughto semiconductor spotlights.Lamps, general Discharge lampsThermal radiators

Electroluminescentluminaires




The electric light sources can bedivided into three main groups,divided according to how theyconvert electrical energy intolight. One group is that of thethermal radiators, this containsincandescent lamps and tung-sten halogen lamps. The secondgroup is made up of the dischargelamps; this consists of a largespectrum of light sources, e. g.

all forms of fluorescent lamps,sodium vapour lamps and metalhalide lamps. The third groupconsists of the semiconductorswith the LEDs.

E GuideLighting technology | Lamps

Lamps, general

Lamp overview Lamp designation



330

LED A QT (12V) QT, QPAR TC T HIT HST

Lamp power P (W) 1.7-42 100-150 20-100 75-1000 9-36 24-58 20-400 50-100

Luminous ux (lm) 25-3200 1380-

2220

320-2200 1100-

22000

600-2800 1750-5200 1700-35000 2400-5000

Luminous efcacy(lm/W)

30-75 15 22 22 78 90 88-97 50

Light colour various ww ww ww ww, nw, dw ww, nw, dw ww, nw ww

Colour tempera-ture TF (K)

1700-10000 2700 3000 3000 2700-6500 2700-6500 3000-4200 2550

Colour renditionindex Ra

1b-2 1a 1a 1a 1b 1b 1b 1b

Colour renditionindex Ra

70-85 100 100 100 80-89 80-89 80-89 83

Service l ie t (h) 50000 1000 3000-5000 2000 8000-12000 12000-20000 9000-12000 10000-15000

Dimming behavior + + + + + + - -Brilliance + + + + - - + +

Start up behavior + + + + + + - -


E GuideLighting technology | Lamps | Lamps, general

Lamp overview




E GuideLighting technology | Lamps | Lamps, general

Lamp designation

AbbreviationsUsual codes for lamps in theGuide. The letters in brackets arenot used in practice, this resultsin the abbreviations given on

the right.

Abbreviations for identifyingspecial versions are separatedfrom the code by a dash.

Letter codeThe 1st letter refers to the methodof light generation.

The 2nd letter identifies the bulbmaterial on incandescent lampsor the gas fillings on dischargelamps.

The 3rd letter or combination of letters refers to the bulb shape.





Thermal radiators

Thermal radiators generate lightby using an incandescent metalfilament. As the temperatureincreases the spectrum of lightshifts from the red heat of thefilament to warm white light.Characteristic features are lowcolour temperature, excellentcolour rendition and brillianceas a point light source.

General service lamps Tungsten halogenlamps

R and PAR lamps

Halogen reflectorlamps



333

100

80

60

20

0

40

800

%

400 500 700600300

100

80

60

40

20

20(%)U/U

n

F(%) 2800 K

2700 K

2600 K

2500 K

2400 K

2300 K

2200 K

2100 K2000 K

100806040

0,500,400,30

0,26

0,34

0,42

x

y

dw

ww4000 k

5000 k

nw


A low colour temperature ischaracteristic for the generalservice lamp. It is perceived asbeing warm. The continuousspectrum of the incandescent

lamp results in an excellent col-our rendition. As a point lightsource with high luminance itproduces brilliance. Incandescentlamps can be dimmed withoutproblem. They do not require anyadditional equipment for theiroperation. The disadvantages

Properties

E GuideLighting technology | Lamps | Thermal radiators

General service lamps

The general service lamp is a ther-mal radiator. Electrical currentcauses a metal filament to glow.Part of the radiated energy is vis-ible as light. When dimming, thereducing temperature causes thelight spectrum to shift towardsthe range of longer wavelengths– the warm white light of theincandescent lamp changes tothe red heat of the filament.

The maximum radiation is in theinfrared range. A lot of thermalradiation is generated in com-parison to the visible component;conversely there is very little UV radiation. The continuous spec-trum of the incandescent lampresults in an excellent colourrendition.

Physics

Relat ive spectral d istr ibution Colour temperature

Shapes Incandescent lamps are availableas A-lamps (All-purpose lamps)in many forms. Their bulbs can beclear, matt or white. The light isemitted in all directions.

Dimming behaviour of incandes-cent lamps. Relative luminousflux F and colour temperaturein dependence on the relativevoltage U/Un. Voltage reductioncauses an over-proportional dropin luminous flux.

of incandescent lamps are lowluminous efficacy and a relativelybrief nominal service life.



334

100

80

60

40

20

20(%)U/U

n

F(%) 2800 K

2700 K

2600 K

2500 K

2400 K

2300 K

2200 K

2100 K2000 K

100806040

100

80

60

20

0

40

800

%

400 500 7006003000,500,400,30

0,26

0,34

0,42

x

y

dw

ww4000 k

5000 k

nw



R and PAR lamps

A low colour temperature ischaracteristic for the reflectorand parabolic aluminised reflectorlamps. The continuous spectrumof the incandescent lamp results

in an excellent colour rendition.As a point light source with highluminance it produces brilliance.They do not require any additionalequipment for their operation.

Properties

The incandescent lamp is a ther-mal radiator. Electrical currentcauses a metal filament to glow.Part of the radiated energy is vis-ible as light. When dimming, thereducing temperature causes thelight spectrum to shift towardsthe range of longer wavelengths– the warm white light of theincandescent lamp changes tothe red heat of the filament.

The maximum radiation is in theinfrared range. A lot of thermalradiation is generated in com-parison to the visible component;conversely there is very little UV radiation. The continuous spec-trum of the incandescent lampresults in an excellent colourrendition.

Physics


Shapes The R (Reflector) lamps areblown from soft glass and directthe light due to their shape anda partial mirror coating on theinside.

The PAR lamps are manufacturedfrom pressed glass in order toachieve high resistance to tempera-ture change and high accuracyof shape. The parabolic reflectoris available with different half peak spreads and produces adefined beam emission angle. Oncoolbeam lamps, a subgroup of the PAR lamps, a dichroic mirror

coating is used. Dichroic reflec-tors focus the visible light butallow a large part of the thermalradiation to pass through unaf-fected. This allows the thermal


Left: reflector lamp with softglass bulb and ellipsoid reflectorwith moderate focusing power.Right: reflector lamp with pressedglass bulb and powerful parabolic

reflector

load on the illuminated objects tobe reduced by approximately half.

The disadvantages of incandes-cent lamps are low luminousefficacy and a relatively brief nominal service life.



335

100

80

60

40

20

20(%)U/U

n

F(%) 2800 K

2700 K

2600 K

2500 K

2400 K

2300 K

2200 K

2100 K2000 K

100806040

100

80

60

20

0

40

800

%

400 500 7006003000,500,400,30

0,26

0,34

0,42

x

y

dw

ww4000 k

5000 k

nw



Tungsten halogen lamps

The tungsten halogen lamp emitsa whiter light than conventionalincandescent lamps. Its light col-our is in the range of warm white.Due to the continuous spectrum,

the colour rendition is excellent.Its compact form makes the tung-sten halogen lamp an ideal pointlight source. The particularly gooddirectability of the light producesbrilliance. The luminous efficacyand life of tungsten halogenlamps is above that of ordinary

Properties

Halogens in the gas filling reducethe material loses of the fila-ment caused by evaporation andincrease the performance of thelamp. The evaporated tungstencombines with the halogen toform a metal halide, and is chan-nelled back to the filament.The lamp‘s compact shape notonly enables the temperatureto increase but also allows an

increase in the gas pressure, whichreduces the tungsten‘s rate of evaporation. As the temperatureincreases the light spectrum shiftstowards the short wavelengthrange – the red heat of the fila-ment becomes the warm whitelight of the incandescent lamp. Alot of thermal radiation is gener-ated in comparison to the visiblecomponent; conversely there isvery little UV radiation. The tung-sten halogen reflector lamp emitsa continuous spectrum and thusproduces an excellent colourrendition.

Physics


Shapes Tungsten halogen lamps areavailable for operation on mainsvoltage. They usually have a spe-cial fixing. Some feature a screwfixing and an additional externalglass capsule and can be used just like conventional incandes-cent lamps. The advantages of the low-voltage halogen lampprimarily concern the high lumi-nous power for its small dimen-sions. The lamp enables compactluminaire designs and a verynarrow focussing of the light.Low-voltage halogen lamps areavailable for different voltages

and in various shapes and mustbe powered via transformers. Thelamps emit light in all directions.Halogen lamps with low-pressuretechnology are permitted for all


From left to right: tungsten halo-gen lamp for nominal voltagewith E27 fixing and envelopingcapsule, with bayonet fixing, withdouble-ended fixing. Low-voltage

halogen lamp with axial filament

corresponding luminaires. Halo-gen lamps without low-pressuretechnology are only permitted inluminaires with protective cover.The advantages of the low-pres-sure version are improved lumi-nous flux throughout the entireservice life.

incandescent lamps. Tungstenhalogen lamps can be dimmedand do not require any additionalcontrol gear; low-voltage halogenlamps, however, must be powered

via transformers.



336

100

80

60

40

20

20(%)U/U

n

F(%) 2800 K

2700 K

2600 K

2500 K

2400 K

2300 K

2200 K

2100 K2000 K

100806040

100

80

60

20

0

40

800

%

400 500 7006003000,500,400,30

0,26

0,34

0,42

x

y

dw

ww4000 k

5000 k

nw



Halogen reflector lamps

The tungsten halogen reflec-tor lamp emits a whiter lightthan conventional incandescentlamps. Its light colour is in therange of warm white. Due to

the continuous spectrum, thecolour rendition is excellent.Its compact form makes thetungsten halogen reflector lampan ideal point light source. Theparticularly good directabilityof the light produces brilliance.The luminous efficacy and life of tungsten halogen reflector lampsis above that of ordinary incan-descent lamps. Tungsten halogenreflector lamps can be dimmed

Properties

Halogens in the gas filling reducesthe material loses of the filamentcaused by evaporation and increasethe performance of the lamp. The

evaporated tungsten combineswith the halogen to form a metalhalide, and is channelled back tothe filament. The lamp‘s compactshape not only enables the tem-perature to increase but also allowsan increase in the gas pressure,which reduces the tungsten‘s rateof evaporation. As the temperatureincreases the light spectrum shiftstowards the short wavelengthrange the red heat of the filamentbecomes the warm white light of the incandescent lamp. A lot of thermal radiation is generated incomparison to the visible com-

Physics

Relative spectral distribution Colour temperature

Shapes Tungsten halogen reflector lampsare available for operation onmains voltage. They usually havea special fixing. Some feature ascrew fixing and an additionalexternal glass capsule and can beused just like conventional incan-descent lamps. The advantagesof the low-voltage halogen lampprimarily concern the high lumi-nous power for its small dimen-sions. The lamp enables compactluminaire designs and a verynarrow focussing of the light.Low-voltage halogen reflectorlamps are available for different

voltages and in various shapesand must be powered via trans-formers. They are available withdifferent half peak spreads. Theversions with coolbeam reflectors


Low-voltage halogen lamp withpin base and coolbeam reflectormade of glass, with aluminiumreflector for higher performance.

radiate the heat away to the sidesand reduce the thermal loadingin the focused beam. The halogenparabolic reflector lamp combinesthe advantages of halogen tech-nology with the technology of the PAR lamps.

and do not require any additionalcontrol gear; low-voltage halogenreflector lamps, however, must bepowered via transformers. Nar-row or wide beam reflectors are

available. Lamps with coolbeamreflector place less thermal load-ing on the illuminated objects.Lamps with an integrated coverglass permit operation in openluminaires.

ponent; conversely there is verylittle UV radiation. The tungstenhalogen reflector lamp emits acontinuous spectrum and thus

produces an excellent colourrendition.





Discharge lamps

Discharge lamps comprise thoselight sources whereby the genera-tion of light does not rely, or doesnot solely rely, on the tempera-ture of the materials. Dependingon the type, a differentiation ismade between photo lumines-cence and electroluminescence.The light is generated principallyusing chemical or electrical proc-esses. The discharge lamp group

is subdivided into low-pressureand high-pressure lamps.

Fluorescent lamps Metal vapour lampsCompact fluorescentlamps

High-pressuresodium vapour lamps



338

1 2 3

45

7

0,500,400,30

0,26

0,34

0,42

x

y

dw

ww4000 k

5000 k

nw

%100

80

60

20

0

40

800400 500 700600 nm300


E GuideLighting technology | Lamps | Discharge lamps

Fluorescent lamps

With fluorescent lamps, the lightis emitted from a large surfaceand is mainly diffuse light withlittle brilliance. The light coloursof fluorescent lamps are warm

white, neutral white and daylightwhite. Fluorescent lamps featurea high luminous efficacy and longlife. Both starters and controlgear (chokes) are necessary foroperating fluorescent lamps. Theyignite immediately and attaintheir full luminous power after abrief moment. An immediate re-ignition is possible if the currentis interrupted. Fluorescent lampscan be dimmed depending on thecontrol gear.

Properties

The electrode (1) releases elec-

trons (2) that then collide intomercury atoms (3). This causes theelectrons of the mercury atom (4)to become excited, causing themto emit UV radiation (5). In thefluorescent coating (6), the UV radiation is converted into visiblelight (7).

Technology

The fluorescent lamp is a low-pressure discharge lamp thatworks using mercury. The gasfilling consists of an inert gasthat makes the ignition easierand controls the discharge. Themercury vapour emits ultra-violet radiation upon excitation.Fluorescent substances on theinside surface of the dischargetube convert the ultravioletradiation into visible light usingfluorescence. A voltage surgeis used to ignite the lamp. Thediscontinuous spectrum of fluo-rescent lamps has a poorer colour

rendition property than thatof incandescent lamps with acontinuous spectrum. The colourrendition of fluorescent lampscan be improved at the cost of

Physics

Colour temperaturewarm white

Relative spectral distribution

luminous efficacy. Conversely,increasing the luminous efficacycauses a worsening of the colourrendition. The light colour can bein the warm white, neutral whiteor daylight white range, depend-ing on the proportion of the indi-vidual fluorescent substances.



339

T26 18W, 36W, 58W

T16 14W, 35W, 54W

%100

80

60

20

0

40

800400 500 700600 nm300

%100

80

60

20

0

40

800400 500 700600 nm300 0,500,400,30

0,26

0,34

0,42

x

y

dw

ww4000 k

5000 k

nw

0,500,400,30

0,26

0,34

0,42

x

y

dw

ww4000 k

5000 k

nw


Shapes Fluorescent lamps are usuallyshaped as a straight tube, wherebythe luminous power depends onthe length of the lamp. Specialforms such as U-shape or ring-shape fluorescent lamps are avail-able.

Colour temperatureneutral white


Colour temperaturedaylight white


Physics


Fluorescent lamps





Compact fluorescent lamps

By bending or coiling the dis-charge tubes, compact fluores-cent lamps are made shorter thanordinary fluorescent lamps. Theyhave fundamentally the same

properties as the conventionalfluorescent lamps, above all theseare high luminous efficacy andlong life. The relatively small vol-ume of the discharge tubes canproduce a focused light using theluminaire‘s reflector. Compactfluorescent lamps with integratedstarters cannot be dimmed. How-ever, there are types with externalstarter available, which can beoperated on electronic controlgear and allow dimming.

Properties

Physics The fluorescent lamp is a low-

pressure discharge lamp thatworks using mercury. The gasfilling consists of an inert gasthat makes the ignition easierand controls the discharge. Themercury vapour emits ultra-violet radiation upon excitation.Fluorescent substances on theinside surface of the dischargetube convert the ultravioletradiation into visible light usingfluorescence. A voltage surgeis used to ignite the lamp. Thediscontinuous spectrum of fluo-rescent lamps has a poorer colourrendition property than that of incandescent lamps with continu-ous spectrums. The colour rendi-tion of fluorescent lamps can beimproved at the cost of luminous

efficacy. Conversely, increasing

the luminous efficacy causes aworsening of the colour rendi-tion. The light colour can be inthe warm white, neutral white ordaylight white range, dependingon the proportion of the individ-ual fluorescent substances.



341

TC-L 18W, 24W, 36W, 40/55W

TC 5W, 7W,9W, 11W TC-T 18W, 26W,42WTC-D 10W, 13W,18W, 26W

%100

80

60

20

0

40

800400 500 700600 nm300 0,500,400,30

0,26

0,34

0,42

x

y

dw

ww4000 k

5000 k

nw

0,500,400,30

0,26

0,34

0,42

x

y

dw

ww4000 k

5000 k

nw

%100

80

60

20

0

40

800400 500 700600 nm300


Shapes Compact fluorescent lamps areprimarily available as a straighttube. Starters and fluorescentlamp chokes are necessary fortheir operation; on two pin lamps,however, the starters are alreadyintegrated into the end cap. Inaddition to these standard forms,there are also compact fluores-cent lamps with integrated starterand control gear. These featuresa screw-in fixing and can be used just like incandescent lamps.


Compact fluorescent lamps



Physics





342

%100

80

60

20

0

40

800400 500 700600 nm300

%100

80

60

20

0

40

800400 500 700600 nm300

0,500,400,30

0,26

0,34

0,42

x

y

dw

ww4000 k

5000 k

nw

0,500,400,30

0,26

0,34

0,42

x

y

dw

ww4000 k

5000 k

nw



Metal vapour lamps

Metal halide lamps feature excel-lent luminous efficacy whilesimultaneously having goodcolour rendition; their nominalservice life is high. They represent

a compact light source. The lightcan be optically well directed. Thecolour rendition is not constant.Metal halide lamps are availablein the light colours warm white,neutral white and daylight whiteand are not dimmed. Metal halidelamps require both starters andchokes for their operation. Theyrequire an ignition time of severalminutes and a longer cooling-down phase before re-igniting.

Properties On some forms an immediate re-ignition is possible using specialstarters or the electronic controlgear.

Metal halide lamps are compara-ble with high-pressure mercuryvapour lamps in design and func-tion. They additionally contain amixture of metal halides. In addi-tion to increasing the luminousefficacy, improved colour rendi-tion is also attained. Due to com-binations of metals, an almostcontinuous multiline spectrumis produced. Metal halide lampsare available in the light colourswarm white, neutral white anddaylight white. Compared toquartz technology, the lamps withceramic discharge tube featurehigher luminous efficacy and bet-ter colour rendition due to theincreased operating temperature.

Physics








Shapes Metal halide lamps are availableas single-ended or doubled-endedtubular lamps, as elliptical lampsand as reflector lamps. Metal hal-ide reflector lamps combine the

technology of the metal halidelamps with that of the PAR lamps.


Metal vapour lamps

Metal halide lamps with single-ended cap (HIT), double-endedcap (HIT-DE) and metal halidereflector lamp (HIPAR)



344

%100

80

60

20

0

40

800400 500 700600 nm300 0,500,400,30

0,26

0,34

0,42

x

y

dw

ww4000 k

5000 k

nw



High-pressure sodium vapour lamps

High-pressure sodium vapourlamps have excellent luminousefficacy and a high nominal serv-ice life. Their colour rendition ismoderate to good. High-pressure

sodium vapour lamps are oper-ated with a control gear and astarter. They require an ignitiontime of several minutes and acooling-down phase before beingre-ignited. On some forms animmediate re-ignition is possibleusing special starters or the elec-tronic control gear.

Properties

High-pressure sodium vapourlamps are comparable with thehigh-pressure mercury vapourlamps in design and function. The

mixture inside the lamps consistsof inert gases and a mercury-sodium amalgam, whereby theinert gas and mercury componentserves the ignition and stabilisa-tion of the discharge. When thepressure is sufficiently high, avirtually continuous spectrumis produced with a yellowish towarm white light while givingmoderate to good colour rendi-tion.

Physics

Colour temperatureRelative spectral distribution

Shapes High-pressure sodium vapourlamps are available as clearlamps in tubular form and ascoated lamps in ellipsoid form.Furthermore, there are alsodouble-ended compact straighttube lamps, which allow imme-diate re-ignition and representa particularly compact lightsource. One part of the high-pressure sodium vapour lampshas a coated outer capsule. Thiscoating serves only to reducethe lamp luminance and to givea more diffuse light emission, itdoes not contain any fluorescent

substances.





Electroluminescent radiators

In electroluminescent radiators,the electrical energy producesvisible radiation. One of the char-acteristic aspects of light emit-ting diodes, LEDs, is their narrowbanded spectrum, while theiradvantages include a compactshape, high colour density, a longlife, and low power consumption.

LED



346

Anode

Substrate

n-layer

Active region

p-layer

Cathode

%100

80

60

20

0

40

800400 500 700600 nm300


E GuideLighting technology | Lamps | Electroluminescent radiators

LED

Light emitting diodes, LEDs,have extremely long life, impactresistance and low energy con-sumption. When dimmed, thelight colour remains constant.

When connected to the mains,they require control gear toensure the correct operatingcurrent. The point light sourceprovides for precise light controlwhile the plastic encapsulationof the diode acts as protectionand lens. The output of the LEDdecreases with increasing tem-perature. Consequently, goodheat dissipation is important forsmooth operation. Direct solarradiation should be avoidedso too installation near othersources of heat. With an averagerated life of 50,000 hours, LEDsare suitable for long operating

times. As they start instantly andreact directly to control, theyare ideal for quick, dynamic lightscenes. The development of LEDscurrently focuses on more com-

Properties pact shapes, a higher luminousflux, and better luminous efficacyas well as a more economicalproduction process. A further goalis the reduction of production-

related colour deviations. Manu-facturers sort LEDs by luminousflux and dominant wavelengthand give them a bin code anda rating. This sorting of LEDs iscalled binning.

GeneralLEDs are semiconductor diodesthat belong to the group of elec-troluminescent sources. The lightis generated by recombiningcharge-carrier pairs in a semicon-ductor with an appropriate energyband gap. LEDs produce narrow-band radiation. The colour tem-perature remains constant as thelight intensity decreases. LEDs

used for lighting do not produceUV or IR radiation.

Physics

When voltage is applied to thecathode and the anode, the LEDemits light from the barrier layer.Electrons change their energylevel and through recombinationrelease photons at the pn-junc-tion. The wavelength of the lightproduced depends on the semi-conductor materials.

Coloured LEDsLEDs produce a narrow bandedspectral range. The dominantwavelength determines the col-our locus of the LED. Compared tocoloured fluorescent lamps, LEDshave a higher colour density. Thecomposition of the semiconduc-tor material determines the lightspectrum emitted. Differentlycoloured LEDs of the same con-nected load produce differentlevels of luminous flux.

Relative spectral distribution:red, green and blue LEDs

CIE colour triangle with colourloci of red, green and blue LEDs



347

%100

80

60

20

0

40

800400 500 700600 nm300

%100

80

60

20

0

40

800400 500 700600 nm300


Shapes

T-type LEDThe standard T-type LED has aplastic housing measuring 3-5mmfor the wired LED. The shape of the lens determines the lightemission angle. As a light sourcewith a low luminous flux it isused as an orientation or a signalluminaire.

SMD LEDWith the “Surface MountedDevice“ (SMD) shape, the compo-nent is glued directly to the cir-cuit board and the contactsare soldered.

COB LEDThe “Chip on Board“ (COB) tech-nology places the chip directly ona circuit board without its ownhousing. The anode and cathodecontact can be made using thin

wires. The chip is sealed to pro-tect it.

White LEDWhite light cannot be producedwith semiconductor materials.Consequently, white light is cur-rently generated using two meth-

ods: RGB mixing or luminescenceconversion. The colour renditionof white LEDs currently approxi-mates a colour rendition indexRa of 90. The light colours avail-able include warm white, neutralwhite, and daylight white LEDs of 2500K to 8000K.

RGB LEDBy combining three light diodeswith the light colours red, greenand blue (RGB), the light colourscan be mixed to produce a widerange of colours, including white.The red, green and blue LEDs canbe controlled to adjust their dif-

ferent light intensities.

Luminescence conversionThe spectrum of coloured LEDscan be converted by using phos-phors as a luminous layer. Pro-

Relative spectral distribution: LEDwith luminescence conversion,warm white

Relative spectral distribution:RGB LED

E GuideLighting technology | Lamps | Electroluminescent radiators

LED

T-type LED SMD LED

COB LED

ducing blue LEDs with yellowphosphors is easier than UV LEDswith RGB phosphors.

High-power LEDHigh-power LEDs are LEDs with apower consumption of over 1W.This includes both SMD and COBLEDs. The key factor is their spe-cial construction that ensuresvery low thermal resistancebetween the chip and the circuitboard. High-power LEDs are usu-ally used on metal core circuitboards requiring special thermalmanagement in the luminaire.





Luminaire technology

Luminaires perform a range of functions. The most importanttask of a luminaire is to direct thelamp‘s luminous flux. The objec-tive here is to distribute light in away that best suits the particulartasks of the luminaire while mak-ing the best possible use of theenergy expended. In addition todesign-related aspects of lumi-naires as a constituent part of

a building‘s architecture, thoseaspects relating to installationand safety are also relevant.

Principles of control-ling light

Lens systemsReflectors

Filters Lighting technologyaccessories

Prismatic systems

Colour mixing




The most essential task of a lumi-naire is to direct the lamp lumens;whereby, a light distribution isstriven for that corresponds tothe particular job of the luminairefor the best possible utilisation of the energy used.A step towards a targeted andspecific light control was real-ised by the introduction of thereflector lamps and PAR lamps.

The light is focused by reflectorsintegrated into the lamp and canbe directed in the desired direc-tion with defined beam emissionangles. The demand for more dif-ferentiated lighting control, forenhanced luminaire efficiencyand improved glare limitation ledto the reflector being taken fromthe lamp and integrated into theluminaire. This means that it ispossible to construct luminairesthat are designed to meet thespecific requirements of the lightsource and the task.

E GuideLighting technology | Luminaire technology

Principles of controlling light

Reflectance Transmission Absorption

Refraction Interference




E GuideLighting technology | Luminaire technology | Principles of controlling light

Reflectance

In the case of reflection, the lightincident on a surface is fully orpartially reflected, dependingon the reflection factor of thesurface. Besides reflectance

the degree of diffusion of thereflected light is also significant.In the case of specular surfacesthere is no diffusion. The greaterthe diffusing power of the reflect-ing surface, the smaller the spec-ular component of the reflectedlight, up to the point of com-pletely diffused reflection whereonly diffuse light is reflected.

Luminous intensity distribution Iin the case of diffuse reflection

Luminous distribution L in thecase of diffuse reflection. It is thesame from all angles of vision.

Luminous intensity distribution inthe case of mixed reflection

Luminous intensity distribution inthe case of specular reflection

Diffusion

Specular reflection is a key factorin the construction of luminaires;by using suitable reflector con-tours and surfaces, it enables a

targeted control of light and isalso responsible for the magni-tude of the light output ratio.

Surface forms

Specular reflection of parallelbeams of light falling onto a flatsurface (parallel optical path)

Concave surface(converging beam)

Convex surface(diverging beam)



351

0AINTFINISH

7HITE n

0ALEYELLOW n

n

"EIGEOCHREORANGEMIDGREY n

DARKGREYDARKRED nDARKBLUEDARKGREEN

0ALEGREENLIGHTREDPALEBLUELIGHTGREY

-ETALS

!LUMINIUMHIGHLYSPECULAR n!LUMINIUMANODISEDMATTFINISH n!L UMI NI UMM ATT FI NI SH n 3ILVERPOLISHED #OPPERPOLISHED n.0#HROMEPOLISHED n03TEELPOLISHED n

"UILDINGMATERIALS

0LASTERWHITE n'YPSUM n%NAMELWHITE n-ORTARLIGHT n#ONCRETE n'RANITE n"RICKRED n'LASSCLEAR n



Reflectance

Reflectances of common metals,paints and building materials

Reflectances





Transmission describes how thelight incident on a body is totallyor partially transmitted depend-ing on the transmission factorof the given body. The degree of

diffusion of the transmitted lightmust also be taken into account.In the case of completely trans-parent materials there is no dif-fusion. The greater the diffusingpower, the smaller the directedcomponent of the transmittedlight, up to the point where onlydiffuse light is produced. Trans-mitting materials in luminairescan be transparent. This appliesto simple front glass panels orfilters that absorb certain spec-tral regions but transmit others,thereby producing coloured lightor a reduction in the UV or IRrange. Occasionally diffusing

materials, e.g. opal glass or opalplastics, are used for front coversin order to reduce lamp lumi-nance and to help control glare.

Luminous intensity distribution Iin the case of diffuse transmission

Luminous distribution L in thecase of diffuse transmission. It isthe same from all angles of vision.

Luminous intensity distribution inthe case of mixed transmission

Luminous intensity distributionin the case of mixed transmissionthrough transparent material

Transmission

Absorption describes how thelight incident on a surface istotally or partially absorbeddepending on the absorption

factor of the given material. Inthe construction of luminairesabsorption is primarily used forshielding light sources; in thisregard it is essential for visualcomfort. In principle, however,absorption is not desirable sinceit does not direct but ratherwastes light, thereby reducingthe light output ratio of theluminaire. Typical absorbing ele-ments on a luminaire are blackmultigroove baffles, anti-dazzlecylinders, barn doors or louvresof various shapes and sizes.

Absorption



353

N N

NN

'



Refraction

When beams of light enter a cleartransmitting medium of differingdensity, e.g. from air into glassand vice versa from glass intothe air, they are refracted, i.e. the

direction of their path is changed.In the case of objects with paral-lel surfaces there is only a parallellight shift, whereas prisms andlenses give rise to optical effectsranging from change of radiationangle to the concentration ordiffusion of light to the creationof optical images. In the construc-tion of luminaires refracting ele-ments such as prisms or lensesare frequently used in combina-tion with reflectors to control thelight.

When transmitted from onemedium with a refractive indexof n1 into a denser medium witha refractive index of n2, the raysof light are diffracted towardsthe axis of incidence (ε1>ε2).For the transition from air toglass the refractive index isapprox. n2/n1=1.5.

When transmitted through amedium of a different density,rays are displaced in parallel.

Introduction

Prisms and lenses Typical ray tracing of parallelincident light through an asym-metrical prism structure (topleft), symmetrical ribbed prismstructure (top right), Fresnel lens(bottom left) and collecting lens(bottom right).

Refractive index There is an angular limit εG forthe transmission of a ray of lightfrom a medium with a refrac-tive index of n2 into a mediumof less density with a refractiveindex of n1. If this critical angleis exceeded the ray of light isreflected into the denser medium(total internal reflection). For thetransition from glass to air theangular limit is approx. εG = 42°.Fibre-optic conductors functionaccording to the principle of totalinternal reflection (right).



354



Interference

Interference is described as theintensification or attenuation of light when waves are superim-posed. From the lighting pointof view, interference effects are

exploited when light falls onextremely thin layers that lead tospecific frequency ranges beingreflected and others being trans-mitted. By arranging the sequenceof thin layers of metal vapouraccording to defined thicknessesand densities, selective reflectancecan be produced for specific fre-quency ranges. The result can bethat visible light is reflected andinfrared radiation transmitted,for example – as is the case withcool-beam lamps. Reflectors andfilters designed to produce col-oured light can be manufacturedusing this technique. Interference

filters, so-called dichroic filters,have a high transmission factorand produce particularly distinctseparation of reflected and trans-mitted spectral ranges.Mirror-finish reflectors with goodmaterial quality are free of inter-ference.




E

Reflectors are probably themost important elements in theconstruction of luminaires forcontrolling light. Reflectors withmirrored surfaces are mainlyused. Diffusely reflective surfaces– usually white or with a mattfinish are also used.Reflectors – general Darklight reflectorsParabolic reflectors

Spherical reflectors Elliptical reflectorsInvolute reflectors

Double reflectorsystems

GuideLighting technology | Luminaire technology

Reflectors




E GuideLighting technology | Luminaire technology | Reflectors

Reflectors – general

Anodized aluminium or chrome-plated or aluminium-coatedplastic are generally used forreflectors. Plastic reflectors arereasonably low-priced, but can

only take a limited thermal loadand are therefore not so robustas aluminium reflectors, whosehighly resistant anodized coatingprovides mechanical protectionand can be subjected to hightemperatures.

Material

Surface

Reflector surfaces: specular Matt

Textured Facetted

The surfaces of the reflectors can

have a specular or matt finish.The matt finish produces greaterand more uniform reflector lumi-nance. If the reflected light beamis to be slightly diffuse, be it toattain softer light or to balanceout irregularities in the light dis-tribution, the reflector surfacesmay have a facetted or texturedfinish. Metal reflectors mayreceive a dichroic coating, whichcan control light luminous colouror the UV or IR component.



357


E

Reflectors can be divided into dif-ferent reflectance groups: mirror-finish, specular and satin matt.Mirror-finish reflectors withgood material quality are free of

interference. The high reflectanceand the highest specular qualitymake the luminaire appear as a“dark hole” in the ceiling. Reflec-tions of items such as bright roomfurnishings are possible in thereflector. A further characteristicis high luminance contrasts in thereflector.The lower specular quality of specular reflectors reduces thedisadvantages associated withhighly specular reflectors.Satin-matt reflectors are alsointerference free if the anodisingthickness is sufficient. The highreflectance and the low specu-

lar quality lead to low contrastwithin the reflector. This meansthat disturbing reflections fromroom furnishings are preventedand it also produces a calm roomambiance. Diffuse surface reflec-tion can cause luminances of >200cd/m2 in the area beyondthe cut-off angle. There is usuallyno disturbance on VDU screens.

Reflectance

Reflectance of reflectors:mirror-finish

Specular

Satin matt

GuideLighting technology | Luminaire technology | Reflectors

Reflectors – general

Light distribution is determinedto a large extent by the form of the reflector. Almost all reflectorshapes can be attributed to theparabola, the circle or the ellipse.

Geometry

Circle Ellipse Parabola Hyperbola

Path of beam from point lightsources when reflected by:



358

A


E

The most widely used reflectorsare parabolic reflectors. They allowlight to be controlled in a varietyof ways, e.g. narrow-beam, wide-beam or asymmetrical distribu-

tion, and provide for specific glarelimitation characteristics. If thereflector contour is constructedby rotating a parabola or parabolicsegment around its own axis, theresult is a reflector with narrow-beam light distribution. In the caseof linear light sources a similareffect is produced when rectan-gular reflectors with a paraboliccross section are used.

Reflector contour

Reflector contours for parallelbeam/parabola

Converging beam/ellipse

Diverging beam/hyperbola


Parabolic reflectors

Converging-diverging beam

In the case of parabolic reflectors,the light emitted by a light sourcelocated at the focal point of theparabola is radiated parallel tothe parabolic axis.If there is a short distance betweena parabolic reflector’s focal pointand its apex, the reflector will actas a shield to direct rays.If this distance is large, then thedirect rays will not be shielded.

However, these can be shieldedusing a spherical reflector.

Focal point

If the reflector contour is con-structed by rotating a parabolicsegment around an axis, which isat an angle to the parabolic axis,the result is a reflector with wide-beam to batwing light distribu-tion characteristics. Beam anglesand cut-off angles can thereforebasically be defined as required,which allows luminaires to beconstructed to meet a wide rangeof light distribution and glarelimitation requirements.

Wide-beam lightdistribution



359

A

A



Parabolic reflectors

Parabolic reflectors can also beapplied with linear or flat lightsources, e.g. PAR lamps or fluores-cent lamps, although these lampsare not located at the focal point

of the parabola. In these cases,the aim is not so much to produceparallel directional light but opti-mum glare limitation. In this typeof construction, the focal point of the parabola lies at the nadir of the opposite parabolic segments,with the result that no light fromthe light source located above thereflector can be emitted abovethe given cut-off angle. Suchconstructions are not only pos-sible in luminaires, but can alsobe applied to daylight controlsystems; parabolic louvres, e.g. inskylights, direct the sunlight sothat glare cannot arise above the

cut-off angle.

Linear light sources




E

In the case of the conventionalparabolic reflectors clearly definedlight radiation – and effectiveglare limitation – is only possiblefor exact, point light sources.

When using larger radiatingsources, e.g. compact fluorescentlamps, glare will occur above thecut-off angle; glare is visible inthe reflector, although the lampitself is shielded. By using reflec-tors with a variable parabolicfocal point (so-called darklight


In the case of spherical reflec-

tors the light emitted by a lamplocated at the focal point of thesphere is reflected to this focalpoint. Spherical reflectors areused predominantly as an aid inconjunction with parabolic reflec-tors or lens systems. They directthe luminous flux forwards ontothe parabolic reflector, so that italso functions in controlling the

Spherical reflectors

With involute reflectors the lightthat is emitted by the lamp isnot reflected back to the lightsource, as is the case with spheri-cal reflectors, but reflected pastthe lamp. Involute reflectors aremainly used with discharge lampsto avoid the lamps over-heatingdue to the retro-reflected light,which would result in a decreasein performance.

Involute reflectors

Darklight reflectors reflectors) this effect can beavoided; brightness will thenonly occur in the reflector of larger radiating sources belowthe cut-off angle, i.e. when the

light source is visible.

light, or to utilize the light radi-

ated backwards by means of retroreflection back towards the lamp.




Double reflector systems consistof a primary and secondary reflec-tor. The primary reflector alignsthe light in a parallel or narrowly

focused beam and directs it to thesecondary reflector. The actuallight distribution is created by thesecondary reflector. The directview of upon the high luminanceof the lamp is prevented withdouble reflector systems, result-ing in improved visual comfort.The precise alignment of thereflectors determines the effi-ciency of the system.

Double reflector systems


In the case of elliptical reflec-tors the light radiated by a lamplocated at the first focal pointof the ellipse is reflected to thesecond focal point. The second

focal point of the ellipse can beused as an imaginary, secondarylight source.Elliptical reflectors are used inrecessed ceiling washlights to pro-duce a light effect from the ceilingdownwards. Elliptical reflectors arealso ideal when the smallest pos-sible ceiling opening is required fordownlights. The second focal pointwill be an imaginary light sourcepositioned at ceiling level; it is,however, also possible to controlthe light distribution and glarelimitation by using an additionalparabolic reflector.

Elliptical reflectors

Double-focus downlight Double-focus wallwashers

Spotlight




E

Lenses are used almost exclusivelyfor luminaires for point lightsources. As a rule the optical sys-tem comprises a combination of one reflector with one or morelenses.

Collecting lenses Sculpture lensFresnel lenses

Spread lens Softec lensFlood lens

Projecting systems


Lens systems




E GuideLighting technology | Luminaire technology | Lens systems

Collecting lenses direct the lightemitted by a light source locatedin its focal point to a parallelbeam of light. Collecting lensesare usually used in luminaire

constructions together with areflector. The reflector directs theoverall luminous flux in beamdirection, the lens is there to con-centrate the light. The distancebetween the collecting lens andthe light source is usually vari-able, so that the beam anglescan be adjusted as required.

Collecting lenses

Fresnel lenses consist of concen-

trically aligned ring-shaped lenssegments. The optical effect of these lenses is comparable to theeffect produced by conventionallenses of corresponding shapeor curvature. Fresnel lenses are,however, considerably flatter,lighter and less expensive, whichis why they are frequently usedin luminaire construction in placeof converging lenses. The opticalperformance of Fresnel lensesis confined by aberration in theregions between the segments;as a rule the rear side of thelenses is structured to maskvisible irregularities in the lightdistribution and to ensure thatthe beam contours are soft.

Fresnel lenses Luminaires equipped with Fresnel

lenses were originally mainly usedfor stage lighting but are nowalso used in architectural light-ing schemes to allow individualadjustment of beam angles whenthe distance between luminairesand objects varies.

The sculpture lens producesasymmetrical light distribution.It spreads the beam of light inone axis, while leaving the lightdistribution unchanged on theother axis. The parallel ribbed lensproduces a vertical oval when theribs are orientated horizontally.

Sculpture lens

The spread lens is used with wall-washers. It produces asymmetricallight distribution. It spreads thebeam of light in one axis, whileleaving the light distributionunchanged for the other axis.The parallel ribbed lens producesa vertical oval when the ribs areorientated horizontally. This pro-

duces very even wallwashing.

Spread lens




The flood lens spreads the beamsymmetrically. In addition, thistextured lens gives softer transi-tion at the beam edge.

Flood lens

E GuideLighting technology | Luminaire technology | Lens systems

Projecting systems comprise anelliptical reflector or a combina-tion of spherical reflector and

condenser to direct light at acarrier, which can be fitted withoptical accessories. The light isthen projected on the surface tobe illuminated by the main lens inthe luminaire.Image size and beam angle can bedefined at carrier plane. Simpleaperture plates or iris diaphragmscan produce variously sized lightbeams, and contour masks can beused to create different contourson the light beam. With the aid of templates (gobos) it is possible toproject logos or images.

Projecting systems

Projector with optical system: auniformly illuminated carrier (1)is focused via a lens system (2).

The ellipsoidal projector (left)with high light output, and thecondenser projector (right) forhigh quality definition.

The ability of the Softec lens

results in a soft beam. This can beproduced via a textured or frostedglass. Softec lenses are used tosmooth out visible striations fromreflector lamps. As a lamp cover,it prevents dazzle by reducing thelamp luminance.

Softec lens

In addition, different beam anglesor image dimensions can beselected depending on the focal

length of the lenses. In contrastto luminaires for Fresnel lenses itis possible to produce light beamswith sharp contours; soft con-tours can be obtained by settingthe projector out of focus.



365

T (%)100

80

60

20

0

40

8004 00 5 00 700600 nm300

Standard lighttype AT = 47%

T (%)100

80

60

20

0

40

800400 500 700600 nm300

Standard light type AT = 65%

T (%)100

80

60

20

0

40

800400 500 700600 nm300



E

Filters are optically effective ele-ments which allow selective trans-mission. Only part of the incidentbeam is transmitted; consequently,either coloured light is producedor invisible beam components(ultraviolet, infrared) are filteredout. Filter effects can be attainedusing selective absorption or usinginterference. The filters‘ perme-ability to light is known as trans-

mittance.

Types of filters Corrective filtersColour filters

Protective filters


Filters



366

T (%)100

80

60

20

0

40

800400 500 700600 nm300


T (%)100

80

60

20

0

40

800400 500 700600 nm300


T (%)100

80

60

20

0

40

800400 500 700600 nm300


T (%)100

80

60

20

0

40

800400 500 700600 nm300



Absorption filters absorb certainspectral ranges and transmit theremaining radiation. The absorp-tion process causes the filters tobecome hot. The separation of

transmitted and reflected spectralcomponents is not as exact aswith interference filters and leadsto a reduced edge steepness of the transmittance. Consequently,coloured glass filters create ratherunsaturated colours. They havegreat longevity however.

Types of filters


Filters

Interference filters (edge filters)are classed as reflection filtersand give a high transmittanceand an exact separation of trans-mitted and reflected spectral

components. Glass filters coatedwith an interference coating canproduce saturated colours. Anaccumulation of heat is avoidedsince reflection, and not absorp-tion, takes place. The reflectionspectrum is dependent on theangle of observation. Due to thevaporised coating, their scuff resistance is less than that of absorption filters.

Absorption filter

Reflection filter

Magenta

Amber

Colour filters only transmit a cer-tain part of the coloured, visiblespectrum, whereby the remainingcomponents of the radiation are

filtered out. Colour filters made of plastic film are not heat resistant.Conversely, heat is not so criticalfor glass filters and, to an extent,they are resistant to temperaturechange. Absorption filters madeof coloured glass attain lowercolour saturation compared tointerference filters. The colour-filtering property of interferencecolour filters is not immediatelyapparent – they do not look col-oured.

Colour filtersProperties

Night Blue

Sky Blue



367

T (%)100

80

60

20

0

40

800400 500 700600 nm300


T (%)100

80

60

20

0

40

800400 500 700600 nm300



In architectural lighting too, col-ours from the daylight spectrumare felt to be natural: Magenta(conditions of light at sunset),Amber (atmospheric light at sun-

rise), Night Blue (clear night sky)and Sky Blue (light of the sky byday). In scenic lighting, all coloursof light come into play for high-lighting and forming contrasts. Inpractice, when illuminating col-oured surfaces, it is recommend-able to perform lighting tests.

Colour filtersApplications


Filters

Corrective filters designed asconversion filters will increase orreduce the colour temperature of the light source due to the spec-tral progression of the transmis-sion. Skintone filters only correctthe lamp‘s light spectrum in thegreen and yellow spectral rangeand thereby produce a very natu-ral and pleasant effect on skintones. Daylight-conversion filters

transform the warm white colourtemperature in the range of theneutral white colour of light, i.e.from 3000K to 4000K.

Corrective filtersProperties

Corrective filtersApplications

Skintone Daylight

Skintone filters are colour filterswhich improve the effect of natu-ral warm colours, especially thecolours of the skin. It is beneficialto use Skintone filters in commu-nication areas, such as those of restaurants or cafés.

Conversion filters are used toadapt the warm white [light col-our=1961] from halogen lampsto daylight lighting. Furthermore,by using daylight-conversionfilters in warm white illuminatedareas, it is also possible to createzones with neutral white lightatmosphere.



368

T (%)100

80

60

20

0

40

800400 500 700600 nm300


T (%)100

80

60

20

0

40

800400 500 700600 nm300



E GuideLighting technology | Luminaire technology | Filters

Protective filters

UV filters are suitable for com-pletely blocking ultravioletradiation while allowing optimaltransmission of visible light. Theseparation between reflexion

and transmission takes place at400nm. The steeper the edge of the transmission curve, the lessthe will be the colour distortionin the visible spectrum. UV filtersare transparent (clear), the trans-mission is directional.

Properties

UV filter

IR filter

Applications Filtering out virtually all the ultra-violet radiation effectively delaysthe photochemical process of decay in textiles, watercolours,

historic documents, artworks andother exhibits that are sensitiveto light. This particularly appliesto the bleaching of colours and toyellowing. In practice, since theUV component of high-pressuredischarge lamps is already reducedby prescribed safety glasses,the highest ultraviolet loadingis found from non-capsulatedtungsten halogen lamps.

The use of infrared filters signifi-cantly reduces the thermal loadand thus decreases the heat onan object or its surface. Materialssensitive to heat and humiditycan thus be protected from dryingout or distorting. High propor-tions of infrared radiation areemitted predominantly from lightsources with low luminous effi-cacy, such as thermal radiators.

Infrared filters absorb or reflectthe thermal radiation above800nm while allowing optimaltransmission of visible lightspectrum. The thermal load onobjects is reduced to a minimum.IR filters are transparent (clear),the transmission is directional.

Adequate seperation betweenlamp and filter avoids a build-upof heat within the luminaire.

UV filters are suitable for use in:- art museums- art galleries- natural-science museums

- antiquarian bookshops

IR filters are suitable for use in:- art museums- art galleries- natural-science museums- antiquarian bookshops- food shops

UV filter

IR filter



369

ªªª

ªª

ªª



Prismatic systems

Properties

Typical light distribution of afluorescent lamp with prismaticsystems

Another means of controllinglight optically is to deflect itusing a prism. It is known that thedeflection of a ray of light whenit penetrates a prism is depend-

ent on the angle of the prism. Thedeflection angle of the light cantherefore be determined by theshape of the prism.If the light falls onto the side of the prism above a specific angle,it is not longer refracted butreflected. This principle is alsofrequently applied in prismaticsystems to deflect light in anglesbeyond the widest angle of refrac-tion and, in so doing, to cut outthe light.Prismatic systems are primarilyused in luminaires that take fluo-rescent lamps to control the beamangle and to ensure adequate

glare limitation. This means thatthe prisms have to be calculatedfor the respective angle of inci-dence and combined to form alengthwise oriented louvre or

shield which in turn forms theouter cover of the luminaire.




E

Many luminaires can be equippedwith accessories to change ormodify their photometric quali-ties. Additional glare shields orhoneycomb anti-dazzle screenscan be used to improve glarelimitation.

Anti-dazzle attach-ments

Cross baffleHoneycomb anti-dazzle screen

Framing attachment


Lighting technology accessories

Gobo




E GuideLighting technology | Luminaire technology | Lighting technology accessories

Anti-dazzle attachments Barn doors allow the emittedbeam to be separately restrainedin each of the four directions andprovide improved glare control.A cylindrical anti-dazzle attach-

ment also restricts the view intothe luminaire and reduces glare,but without the flexibility of barndoors.The anti-dazzle attachments areusually externally mounted onthe light head. Glare limitationincreases with the size of the

anti-dazzle attachments. Theblack painted finish absorbs lightand reduces the luminance con-trasts.

Honeycomb anti-dazzlescreen

The honeycomb anti-dazzlescreen is used to control thebeam and reduce glare. Honey-comb anti-dazzle screens are usedwhere there are high demandsfor visual comfort in exhibitionareas. Its limited depth meansthat the honeycomb anti-dazzle

screen can be integrated withinthe luminaire. The black paintedfinish absorbs light and reducesthe luminance contrasts.

Cross baffle The cross baffle is used to reduceglare. Cross baffles are used wherethere are high demands for visualcomfort in exhibition areas. Theblack painted finish absorbs lightand reduces the luminance con-trasts.




Framing attachment

A framing attachment allowsvarious contours of the beamto be adjusted. Reflector-lensimaging systems make it possibleto produce a sharp-edged beam.However, a blurred projectionresults in a soft-edged beam. Theseparately adjustable sliding com-ponents can, for example be usedto create rectangles on walls inorder to highlight objects crisply

around their contours.

Applications:

Museo Deu, El VendrellMuseo Ruiz de Luna Talavera,ToledoGoya exhibition, Madrid

Gobo

The term “gobo“ refers to anaperture plate or image templatethrough which light is projected

by an imaging projector. Gobosmake it possible to project letter-ing or images.Reflector-lens imaging systemscan be used to create crisp imagesor even soft-edged transitionsusing blurred projections.

E GuideLighting technology | Luminaire technology | Lighting technology accessories

Applications:Teattri Ravintola,FinlandAragon Pavilion,SevilleERCO, Lüdenscheid




E

The incorporation of coloured lightopens up interesting possibilitiesfor influencing the atmosphereof rooms. Under electronic con-trol, a large number of colourscan be generated and a smoothcolour changes produced in theluminaire. Varychrome


Colour mixing




Introduction The addition of the name ‚vary-chrome‘ to ERCO luminaires iden-tifies those luminairs whose col-our can be changed dynamically.These luminaires are electronically

controlled to generate variablelight colours by additive colourmixing of the primary colours red,green and blue (RGB technology).They enable an infinitely variableadjustment of different lightcolours.The advantages of colour mixingusing coloured lamps are thatcomplex mechanical componentsare not needed and colour filterswith low transmission are avoided.The term ‚varychrome‘ refers tothe mixing of colours.It is derived from the Latin adjec-tive ‚varius‘ meaning differentand the Greek word ‚chroma‘ for

colour.

E GuideLighting technology | Luminaire technology | Colour mixing

Varychrome

Technology In principle, the colours of thefluorescent lamps can be chosenat will. A multitude of colourscan be mixed from the colouredfluorescent lamps in red, greenand blue. The saturation andthe chromaticity location of thelamps determine the size andshape of the resulting colour tri-angle. The lamps in warm white,neutral white and daylight white

can create various different whitelight colours. The fluorescentlamps primarily produce diffuselight with low brilliance.

LED

The luminaires with LEDs featurea high colour density, whichtherefore results in a large colourtriangles. Characteristic for LEDsare low luminous flux, compactdimensions and long service life.

Fluorescent lamps




E GuideSimulation and calculation

Light simulation and light cal-culation have become essentialcomponents of lighting design.They enable the creative designof lighting solutions on the com-puter and range from the evalua-tion of experimental concepts tophotorealistic presentations. Thecalculation methods are used forquantitative analyses to verify therequired illuminances. However,

to ensure efficient use of thistechnology, knowledge of theunderlying technical principlesis necessary.

Introduction Simu-lation

Planning examples

CalculationsLight simulation

Planning data




Architects and lighting designersuse different methods to conveyideas and technical details andcommunicate these to thoseinvolved in the planning process.Concepts can be visually comparedduring the design phase in orderfor decisions to be made prior toconstruction. Since the 80s theestablished methods of sketch-ing, model making, sampling and

drawings have been extended bytechniques of digital simulation.


Introduction Simulation

Evaluation andpresentation

Quantitative andqualitative simulation

Simulation and imageprocessing

Simulation andreality

Design processInteraction




Evaluation and presentation Comparable to model making,the simulation also differentiatesbetween the working model andthe presentation model. Whilethe working model simplifies the

design process in that it providesrough, sketched variants, thepresentation model includes elab-orate details. In lighting design,sketches, digital drawings andphoto realistic representations arequick visualisation methods. Forfurther examination this is fol-lowed by general light simulation,omitting exact details of materi-als or luminaires. In a subsequentstep, the simulation is improvedby including realistic surfaces andspecific luminaires with accuratephotometrics for detailed plan-ning and presentation purposes.



Simulation and imageprocessing

Simulation is generally associatedwith 3D models and an accuraterepresentation of the lightingeffect. However, for schematicvisualisations, designers oftenuse digital image processing ina 2D or 3D representation. Theadvantage lies in the speed of abstraction and realisation. If thespace to be illuminaited is com-plex then this method does not

allow detailed planning due tolimitations associated with scal-ing and complicated geometry.

Quantitative and qualitativesimulation

In lighting design, simulationincludes two aspects. The quanti-tative simulation provides physi-cally correct, numerical values toverify the illuminances and lampluminances specified. The quali-tative simulation, on the otherhand, focuses on atmosphereand is used by lighting designersto communicate their aestheticidea of the lighting design.






Simulation and reality Often, the quality of a simulationis judged by its proximity to real-ity and the question is asked as towhether the rendering is corrector no more than a photorealistic

representation. The criterion of physically correct data refers tothe numerical values providedby the quantitative simulation.Screen displays or colour print-outs can never give the sameimpression as the actual environ-ment. A photographer controlsthe incident light by openingor closing the aperture and thesame creative approach is takenin the production of a rendering.A further limitation is the rangeof contrasts on the output media.None of the following can cor-rectly reproduce the luminancecontrast which will be seen in

reality: colour printout, screendisplay or the projected imageof a beamer.A photorealistic impression of aqualitative simulation can providea far more authentic representa-tion of the anticipated lightingeffect, such as the progression of light and shadow or reflectionsoff surfaces.

Interaction To visualise changes instantlyduring the processing stage,designers prefer an interactivesimulation. Based on the cur-rent state of the art, however,the interaction is limited by theavailable programs and signifi-cantly depends on the hardware.Interactive aspects in the pro-grams usually include changes tothe geometry, camera position,texture and simple modificationsof the light sources and materialproperties. Currently changes toreflections, complex shadows andindirect light are excluded.






Design process A crucial factor in ensuring anefficient light simulation duringthe design process is a reason-able degree of detailing and theassistance of an expert. Time and

cost can be controlled by limitingthe scope of the presentation.The implementation of the lightsimulation can either be handledby the design office itself or out-sourced to a specialist provider.If handled internally, a renderingcan be prepared in conjunctionwith the design process. Simula-tions, on the other hand, usingan external service providerinvolve considerable informationexchange. This is compensatedfor by the fact that the serviceprovider has greater experience,can produce quicker results andthis can lead to reducing the cost

for the design.The sequence of a light simulationcan be divided into four steps: themodelling of the geometry, thedefinition of materials, the illu-mination of the model, and theactual rendering process.




The light simulation has provento be a useful tool in the visualisa-tion and verification of the light-ing design. Initially, a number of steps are required for the prelimi-nary planning of the rendering:the concept idea and the sketch,the 3D CAD model and the specifi-cation of the light sources and sur-face properties. For professionallight simulations, the designer

uses specialised software suchas 3ds VIZ/Max or DIALux. MostCAD programs are not able tosimulate light with physicallyaccuracy.


Light simulation

3D model LightSurface

Rendering HardwareEvaluation

Software Developments




A simulation is based on the 3Ddata of a room which is used toproduce images. This 3D data canbe imported from simple CADprograms or specialised applica-tions. If the design office alreadyworks with 3D data, they can beimported into the light simulationsoftware. The more sophisticatedthe 3D model, the more realisticthe light simulation will be, but

also of course the more time-consuming.

E GuideSimulation and calculation | Light simulation

3D model

Export and import GeometryTopology




Export and import Where a 3D model exists in aprogram other than the one usedfor light simulation, the data canbe transferred using the exportand import functions. Since 3D

models contain complex data, thedesigner must consider sources of error and allow for manual correc-tions. It is advisable to export thedata simultaneously in severalestablished exchange formats.These 3D CAD exchange formatsinclude DWG, DXF, and 3DS.

E

Topology CAD programs increasingly workwith component-orientated func-tions such as the generation of pil-lars or ceilings. Often, however, itremains unclear as to whether theelements are made up of surfacesor volumes. In the simulationprograms, though, the designer isconfronted with the basic 3D ele-ments without component details;these can be vertex, edge, face/

polygon and surface normal: thevertex with the X, Y and Z coordi-nates, an edge is defined by twovertices and a surface by three.The normal is positioned verti-cally on the surface and revealsits front face. After exportingfrom a component-orientatedCAD program, the designer needsto be prepared eventually for adifferent structure where modi-fications of the geometry aremade in the simulation program.

GuideSimulation and calculation | Light simulation

3D model




E

Geometry Since CAD models can be usedfor other requirements than lightsimulation, the geometry modelfrequently causes problems inthe simulation. While the wire

cables of a banister can easilybe designed as high-resolutioncylinders in a CAD program, thecalculation of the cylinder sur-face is complicated to render.The designer must take this intoaccount as early as possible inthe preparation of the 3D modelin order to review the export set-tings. Since simulations requireextensive calculations and willcontinue to do so, an optimisedgeometry considerably reducesthe work and time involved inproducing light simulations. Small,highly detailed geometries on aseparate, inactive layer can reduce

the calculation time. Similarly, itis advisable to use a material-based layer structure for quickprovisional calculations.

GuideSimulation and calculation | Light simulation

3D model




Materials are recognised solelythrough definition of the surfaceproperties. Depending on thecomplexity required, the simula-tion programs allow for anythingbetween simple and complexsettings.


Surface

Shading Texture




Shading The term ”shading” refers to therepresentation of shades. Thedesigner uses a shader to definethe lighting properties throughthe colour, the reflectance and

the transparency. These deter-mine how the light will appearon an object and affect the sur-roundings. The lighting effect of the material properties alwaysdepends on the type and positionof the light sources and is visibleonly in the combination of shad-ing factors and lighting: hence,shiny spots on reflecting surfacesappear only when the light fromthe light sources shines directlyonto these surfaces.


Surface

Texture To show objects which don‘t havea uniform surface colour, the sur-face can be given a texture. Thismethod, known as "mapping“,places abstract, graphical patternsor photos on the model. Simula-tion programs provide extensivematerial collections in librariesto enable designers to show tex-tures such as wood or exposedconcrete. Using special mapping

methods (bump mapping), micro-structures can be modified so asto give the impression of three-dimensional surfaces.A highly realistic impressionresults if by photos are assignedas textures to polygons. To ensureacceptable quality, the photoshould be high resolution, betaken head-on and contain nolight or other reflections. It mustalso be without distortions dueto the lens.




Where the atmosphere of a roomis to be shown realistically, lightis one of the key factors in thevisualisation. It is essential in theperception of the environmentand determines how rooms andobjects are interpreted. Simulat-ing light using a rendering in a3D model is a time-consumingprocess. To do so, the designercan resort to standardised light

sources or work with digital datarecords to reproduce specificluminaires.


Light

Direct light Indirect light Light sources

Daylight





Light

Direct light Direct light refers to rays of lightshining directly onto the surface.If there is no obstruction thena point on the surface is illumi-nated. The calculation of direct

light requires minimum time andhas been possible from the earlydays of computer graphics. Thishas one significant limitation inthat indirect light is not included:hence, a room illuminated usingonly ceiling washlights would becompletely dark, except for theareas where the ceiling is illumi-nated by the direct light.

Indirect light Indirect light is produced as aresult of light reflecting off a sur-face. The reflectance of the sur-face and the degree of diffusionwhich is often assumed, deter-mines the calculated, reflectedindirect light. To create an accu-rate impression of the room,designers need to calculate asmany interreflections as possibleto achieve a representational

light distribution in the room.It was not until the 1990s thatprogress in hardware allowedsuch a complex calculation. Thecalculation of indirect light isalso known as ”global illumi-nation”.




Light sourcesLight distribution

Simulation programs includegeneral light sources such asspot, point, area and sunlight.The representation of specialluminaires, however, requires an

interface that can import thelight distribution data from theluminaires. These data recordsare available from most luminairemanufacturers and describe thespecific light intensity distribu-tion of each luminaire. The IESformat is a common internationaldata format. Luminaires with anasymmetric light distribution, forexample, cannot be calculatedcorrectly in any other way. Theuse of accessories such as a sculp-ture lens affects the light distri-bution and requires a separatedata record.

Daylight The combination of daylight withdirect sunlight and the diffusesky light, gives simulations theimpression of reality. While thecalculation of daylight for pres-entations and shading studies iseasy, quantitative representationis difficult. Accurate informationon glare control at workplaces andon heat transmission for differenttypes of sun protection glazingcan only be obtained using specialsoftware with appropriate analysistools.


Light

Light sources3D model

Rather than being limited to aquantitative light simulation, if the designer also wants to dem-onstrate the effect of luminairesin the room, the luminaires mustbe available as 3D models. To dothis some luminaire manufactur-ers provide what are called virtualluminaires, which include the 3Dgeometry of the luminaire, thesurface properties, the functional

rotation axis and the light inten-sity distribution. Using inversekinematics, spotlights can be setup quickly and realistically: if thedesigner adjusts the light distri-bution in the room, the movableparts of the luminaires automati-cally follow.




A render engine is an applicationthat allows photorealistic imagesto be generated from a 3D model.Every simulation program hasspecial rendering procedures,each of which has advantagesand disadvantages. Experiencehas shown that every three orfour years, the progress made inhardware performance allowsnew methods of calculation.

Despite the improvements insimulation programs, the qual-ity of the renderings still ulti-mately depends on the skill of the designer.


Rendering

Radiosity Photon mapping Ray tracing





Rendering

RadiosityIn calculations of light distribu-tion using the radiosity processthe rays are emitted by the lightsource and are reflected back by

a surface. This process continueswith a defined number of itera-tions and consequently also takesinto consideration the lightreflecting off other surfaces.A key advantage of radiosity isthe storage of light properties ina grid on the model geometry. Inthis way, the camera angle cansubsequently be changed withoutrequiring a revised calculation.The disadvantage of radiosity isthe effect on the calculation timeof details, spheres or complexscenes with a very large numberof polygons. A relatively coarsegrid of values for quicker calcula-

tion, on the other hand, can leadto errors in the light intensitydistribution.

Photon mappingPhoton mapping is similar tothe ray tracing process. Whileray tracing is based on rays from

the observers/camera position,photon mapping is based on raysemitted from the light source.Photon mapping uses virtual”photons” radiating light into theroom. When they hit a surface,they are reflected back and theluminance values are summated.The photon outputs are storedin a photon map. This map is notbound to the geometry and can beused for simulations with distrib-uted calculations in the network.The camera position can be modi-fied without the need to revisethe calculation – this process,though, is not interactive.The more photons a model has,the more accurate the transitionswill be in the rendering and themore complex the calculation.After a certain number of reflec-tions/iterations, the photon map

Radiosity was one of the firstprocesses used for the calculationof light distribution. Due to thepossibility of calculating indirect,diffuse light, this process is now

widely used. If it is only the cam-era angle that changes in the ani-mation of an architectural model,and not the light, the differentperspectives require no more thana single calculation.

has the required precision. In afurther process, the points canbe merged through gathering.Photon mapping is used as forfurther calculations. To showdetails more accurately, the proc-ess is combined with ray tracing.If the calculation is based exclu-sively on ray tracing it is too com-plex for very small models andvery bright light sources.




Ray tracing(Backward) ray tracing, also calledMonte Carlo ray tracing, is thesecond of the two most popularprocesses used for the calculation

of light distribution. Unlike radios-ity and photon mapping, however,it does not trace a ray of lightfrom the light source. Instead,the rays start from the eye andare followed backwards to themodel and the light sources. If therays from the eye hit a surface,other rays of light are used to seewhether this point reflects lightor contains shadows. The result isshown as pixels on a focal plane.The higher the resolution requiredon the focal plane and the morereflecting surfaces there are, themore rays of light are requiredfor the simulation and the more

complex the calculation becomes.Ray tracing has the advantage of producing exact representationsof details and the smallest shad-ows. Since this method depends


Rendering

on the focal plane, a changeof angle and the line of visionrequires a new calculation. Sceneswith very high contrast ratios aredifficult to represent, as the inci-

dental rays of light for calculationstart from the observer/cameraposition and light apertures suchas small windows in a large wallcan initially be disregarded.




In the same manner as photoscan be evaluated based on tech-nical quality criteria, designerscan check renderings for errors.Where the first impression oftendetermines the general aestheticappearance and the similarity of the lighting effect to the naturalenvironment, there are variouscriteria for a critical technicalevaluation. The desire for maxi-

mum precision in a visualisationhas to be balanced with the com-plexity of detailed modelling andthe time-consuming calculation.So, designers need to find a rea-sonable compromise betweenprecision and speed for the simu-lation.


Evaluation

Image design Artefacts




Image design The image design is assessed,focussing on aesthetic aspects.The perspective - whether withisometry or a central or two-point perspective – determines

the geometric or natural impres-sion. In the same manner, theoverall brightness, contrast andcolour density contribute to arealistic representation. Carefullydefined surfaces create a realisticimpression.


Evaluation




Lighting Objects Correct settings for the calcula-tion of illuminance of objectscan be seen by the details of theobjects. Curved edges that showaliasing effects such as sharp

edges or hard transitions requireless computing power.Often, the calculation times canbe reduced many times over if only a few sample points aresmoothed and gathered. Whilethis shortcut is not visible onsmooth surfaces, the error will bevisible on small, complex forms.This aspect is relevant wheredetails have high luminance con-trasts. This is similar to the lumi-nance progression on componentedges or the weak shadow of anobject due to excessive interpo-lation of the shadow-effect inthe room.

If the grid is too coarse and thecomponents are not accuratelyconnected, the light distributioncan be wrong, resulting, for exam-ple, in light apparently shiningthrough a wall or a ceiling.


Evaluation

Room with few sample points Room with numerous samplepoints

Shadow with strong interpolation Detail shadow with stronginterpolation

Shadow with good interpolation Surfaces with few sample points





Hardware

The effects of faster hardware onthe computing power are moreobvious in light simulation thanin other areas of application,including communication or wordprocessing. To ensure an efficientsimulation process, it is crucialto establish a harmonic balancebetween the processor, the mem-ory and the graphics card.

Processor Main memory Graphics card





Hardware

Processor The processor (CPU, CentralProcessing Unit) is responsiblefor the computing power. Aprocessor working twice as fastas others reduces the calcula-

tion time for a rendering by half.Today the use of dual processorsis recommended. Some worksta-tions have several CPUs instead.For complex tasks, the designercan include other computers inthe network for distributed cal-culations.

Main memory The main memory (RAM, RandomAccess Memory) does not directlyaffect the computing speed. Inthe first instance, it determineshow big the edited scene can be,before the computer writes dataonto the hard drive. This writingprocess is tedious and slows downthe rendering process. Since thedependence here is not linear,the performance drops signifi-

cantly once a certain thresholdis reached. If the calculation fre-quently coincides with hard driveactivity, it is advisable to increasethe main memory.

Graphics card The graphics card determines thedegree of possible interactivitywith the 3D model, specificallyin case of textured objects. Theactual computing speed is hardlyaffected by the graphics card.Some developments, however,show that the graphics card will,in future, also be used for simu-lations.





Software

There is a wide range of programsavailable for light simulation. Thesoftware spectrum covers every-thing from fast, quantitativeanalyses to sophisticated visuali-sation methods. Whether a soft-ware package can produce accu-rate light simulations is indicatedin the manual, which must spec-ify support of global illuminationor radiosity and the IES or Eulum-

dat format. If it does then thedesigner can combine the photo-metric data with the respective3D DXF data.

DIALux Autodesk Radiance




DIALux DIALux is a free of charge lightingdesign software application forcalculation and visualisation. Theprogram is provided by the Deut-sches Institut für Angewandte

Lichttechnik (DIAL – German Insti-tute of Applied Lighting Technol-ogy). The DIALux software givesa quick and easy quantitativeanalysis of a design and includessimple 3D and rendering func-tions. The ULD data format forthe luminaires comprises the 3Dgeometry of the luminaire, thelight intensity distribution, andan article description. The plug-in packages of luminaire manu-facturers contain additional plan-ning data such as maintenancefactors or UGR values.For further information on theDIALux software visit

www.dialux.com.

Autodesk One of the products availablefrom Autodesk is the VIZ software,a program for sophisticated visual-isations. The luminaire data forAutodesk VIZ and also for 3ds Maxinclude a 3D model of the lumi-naire. This includes surface prop-erties, textures and the possiblemotion of components (inversekinematics). Inverse kinematicsallows directional luminaires tobe aligned through a few simpleadjustments. A light simulationrequires additional photometricdata. Autodesk VIZ and 3ds Maxenable radiosity calculations toproduce numerically accuratelight simulations.

Radiance Radiance is a professional lightsimulation program from BerkeleyLab. Its wide range of calculationand analysis tools requires exten-sive knowledge of operating sys-tems and shell commands andconsequently, it is mostly used inresearch institutes and by highlyspecialised companies. Due to itscomplexity, the program is notsuitable for quick representationsof qualitative lighting designs.A physically correct light simu-lation is possible with IES lumi-naire data.


Software



399

100

80

60

20

0

40

800

%

400 500 700600300



Developments

Compared with other technolo-gies such as digital photographyor desktop publishing, the 3Dvisualisation method is far frombeing fully developed. Within afew years, innovations can sig-nificantly change the processes.A number of developments inlight simulation are expected inthe near future.

HDR Light spectrum Real-time rendering



400

100

80

60

20

0

40

800

%

400 500 700600 nm300

%100

80

60

20

0

40

800400 500 700600 nm300



Developments

HDRThe acronym HDR stands for “HighDynamic Range“ and describes atechnical format that stores anddisplays a higher luminance con-

trast. Today’s graphical outputdevices largely work with a “LowDynamic Range” with 255 tonesper colour channel for RGB (8bit).In a scene with a very high lumi-nance contrast, as may be causedby the sun, for example, some are-as can be 100,000 times brighterthan shaded areas. If the imageis saved as a TIFF or jpg file, thecontrast range is compressed suchthat the sun is only 255 timesbrighter than the shadow. Thesun and a white vase can both bewhite in an image and thus fail toreproduce the luminance contrastcorrectly. Because the full range

of contrast levels is maintained inHDR format images (32bit), newpossibilities arise for a subsequentexposure or for renderings. Wherethis is common practice already,

Light spectrumIn most simulation modules, thequality of the colour renditioncannot yet be reproduced becausethe appropriate data and pro-grams are not available. Ratherthan calculating the entire visiblespectrum of light, the softwarecurrently only calculates certainsegments: red, green and blue.Since the various types of lamp

do not have a uniform spectrum,the result is different colourrenditions that are not coveredby the simulation programs. Con-sequently, specifics on the colourrendition of illuminated textiles ina shop, for example, are not pos-sible with the current state of theart. Appropriate future functionswould additionally require thedefinition of the spectral charac-teristics of both the light sourcesand the surfaces..

Real-time renderingSimulations always result insome time delay between inputand result. Consequently realtime calculations would be ideal.Many functions can already beperformed in real time. Often,however, the technical progressalso involves higher representa-tion requirements, which resultsin speed reduction. The real-timetechnology is inspired by com-puter games, where interactiondirectly modifies the imagesequence. Computer game usersbenefit from elaborate prelimi-

nary calculations that are uncom-mon in architectural simulations.The solutions developed by themanufacturers of rendering pro-

grams depend on the hardwarefunctions of powerful graphicscards.

the development of HDR-compat-ible monitors will raise this tech-nology to even higher levels. Inthe medium term, the HDR formatwill replace the current image for-

mats. The RAW photo format isalready a step in this direction.

Incandescent lamp relativespectral distribution

High-pressure discharge lamprelative spectral distribution




The planning and design of lighting installations involvesa number of technical and eco-nomical calculations. Usually,these relate to the average light-ing level or the exact illuminanceat individual points in the room.In addition, it may be useful todetermine the luminance levelsin specific areas of the room,the quality features of the light-

ing such as shadow effects andcontrast rendition or the cost of a lighting installation includingmaintenance cost.


Calculations

Connected load Maintenance FactorPoint illuminances

UGR method Lighting costsUtilisation factormethod




When planning the connectedload, the specific luminaire andlight source used is taken intoconsideration to determine theload, or the number of luminaires,required to achieve the specifiedilluminance. Alternatively, thespecified connected load andlight source can be used to cal-culate the average illuminance.The connected load is used in the

planning of regular luminairegrids. To estimate the approxi-mate lighting levels, luminairemanufacturers provide tablesindicating the illuminances of specified numbers of luminaires.

E GuideSimulation and calculation | Calculations

Connected load

Number of luminaires Illuminance



403

Specifications22227.000Connected load of one luminaireP: 66.0 WConnected load per 100lx

P*: 2.81 W/m2

Em Maintained value of illuminanceDIN EN 12464

f Correction factor from separatecorrection table 0.93

MF Maintenance factor, referencevalue 0.80

Example with P*

Em · a · b · P*n =

P · f · MF

500lx · 12m · 14m · 2.81W/m2

n =66W · 0.93 · 0.81 · 100lx

n = 48

Specifications22227.000Connected load of one luminaireP: 66.0 WConnected load per 100lxP*: 2.81 W/m2

Em Maintained value of illuminanceDIN EN 12464

f Correction factor from separatecorrection table 0.93

MF Maintenance factor, reference

value 0.80

Example with P*

n · P · f · MFEm =

a · b · P*

48 · 66W · 0.93 · 0.80 · 100lxEm =

12m · 14m · 2.81W/m2

Em =499


Number of luminaires The required number of lumi-naires for a specific illuminancecan be calculated on the basis of the connected load values givenfor a luminaire and 100lx. A fur-

ther parameter to be included isthe maintenance factor to ensurethe required illuminance overthe entire period of operation.Since the values only apply to astandard room, the calculationfor other conditions requires acorrection factor.

E

Illuminance In order to calculate the illumi-nance of a specified number of luminaires, the designer requiresinformation on the connectedload per luminaire per 100lx.The maintained level of illumi-nance is determined using themaintenance factor. The main-tained value is the minimumilluminance level that must bemaintained during the opera-

tion of the lighting installation.Since these values only apply toa standard room, the calculationfor other conditions requires acorrection factor.

GuideSimulation and calculation | Calculations

Connected load




The illuminance distribution atcertain points in the room canbe calculated using the inversesquare law. This is based on thefact that the illuminance reduces

with the square of the distancefrom the light source. Indirectlighting components are notincluded in this calculation. Pointilluminances can be calculatedfor a single luminaire or severalluminaires. For confined areaswith individual luminaires, man-ual calculations can be appropri-ate. Where there are a number of luminaires and functional areasin a room, designers use lightingdesign programs that then includethe indirect lighting components.The programs can determine theilluminance for all room surfacesand working planes. The results

are displayed in graphic represen-tations of Isolux charts or falsecolour diagrams.


Point illuminances




To ensure that the required illumi-nance is provided over a period of time, the lighting design includesa maintenance factor MF thattakes into account the reductionof luminous flux. The new valuefor the illuminance of an installa-tion is calculated from the main-tained value of illuminance, andthe maintenance factor. Themaintenance plan specifies the

cleaning frequency of the lumi-naires and the room and thelamp replacement. The main-tained value of illuminance thusdepends on the luminaires, thelamps and the room conditions.

LuminaireMaintenance Factor

Room SurfaceMaintenance Factor


Maintenance Factor

Lamp LumenMaintenance Factor

Lamp Survival Factor



406

Cleaning frequency (a)Environmental conditionsA Open luminairesB Open-top reflectorsC Closed-top reflectors

D Closed reflectorsE Dustproof luminairesF Luminaires with indirect emission

1 2 3P C N D P C N D P C N D0.96 0.93 0.89 0.83 0.93 0.89 0.84 0.78 0.91 0.85 0.79 0.730.96 0.90 0.86 0.83 0.89 0.84 0.80 0.75 0.84 0.79 0.74 0.680.94 0.89 0.81 0.72 0.88 0.80 0.69 0.59 0.84 0.74 0.61 0.520.94 0.88 0.82 0.77 0.89 0.83 0.77 0.71 0.85 0.79 0.73 0.650.98 0.94 0.90 0.86 0.95 0.91 0.86 0.81 0.94 0.90 0.84 0.790.91 0.86 0.81 0.74 0.86 0.77 0.66 0.57 0.80 0.70 0.55 0.45

1 2 3P C N D P C N D P C N D0.99 0.98 0.96 0.95 0.97 0.96 0.95 0.94 0.97 0.96 0.95 0.940.96 0.92 0.88 0.85 0.93 0.89 0.85 0.81 0.90 0.86 0.82 0.780.94 0.88 0.82 0.77 0.91 0.84 0.77 0.70 0.84 0.78 0.72 0.64

Classification of EnvironmentalConditionsP (very clean room) pureC (clean room) clean

N (average conditions) normalD (dirty room) dirty

Cleaning frequency (a)Environmental conditionsDirect emissionDirect/indirect emissionIndirect emission


Luminaire Maintenance Factor The luminaire maintenance factorLMF takes into account the reduc-tion of luminous flux due to thesoiling of the luminaire. It signi-fies the ratio of a luminaire’s light

output ratios before and aftercleaning. The LMF depends on theversion of the luminaire and therelated possibility of soiling. TheLMF classification is indicatednext to the product. At this point,the optimal cleaning frequencymust be defined for the mainte-nance plan.

Room Surface MaintenanceFactor

The room surface maintenancefactor RSMF takes into accountthe reduction of luminous fluxdue to the soiling of the room sur-faces. It signifies the ratio of theroom surface reflectances beforeand after cleaning. The RSMFdepends on the degree of soilingof the room or the ambient condi-tions of a room and the specifiedcleaning frequency. Further influ-

encing factors are the size of theroom and the type of lighting(direct to indirect emission).The room surface maintenancefactor consists of four classifica-tions for room surface deteriora-tion: P pure (very clean room),C clean (clean room), N normal(average conditions) and D dirty(dirty room).


Maintenance Factor



407

2000 4000 6000 8000 10000 12000 14000 16000 18000 200000.95 -- -- -- -- -- -- -- -- --

0.86 0.82 0.75 0.69 0.66 -- -- -- -- --0.99 0.98 0.98 0.97 0.97 0.96 0.96 0.95 0.95 0.94

0.92 0.88 0.85 0.83 0.83 -- -- -- -- --0.96 0.95 0.94 0.93 0.92 0.91 0.90 0.89 0.88 0.88

Hours of operation (h)Tungsten halogen lamps/low-voltageMetal halide lampsHigh-pressure sodium vapour

lampsCompact fluorescent lampsFluorescent lamps


Lamp Lumen MaintenanceFactor

The lamp lumen maintenancefactor LLMF takes into accountthe reduction of luminous fluxdue to the ageing of the lamp.It signifies the ratio of the lamp

lumens at a specific time and thenew value. The current data pro-vided by the lamp manufacturersmust be taken into account here.


Maintenance Factor

Lamp Survival Factor The lamp survival factor LSF takes

into account the variation of thelife of individual lamps from themean life of the lamps. The LSFdepends on the service life of thelamp. The latest data provided bythe lamp manufacturers must betaken into account here. If defec-tive lamps are replaced imme-diately, the lamp survival factorapplied is LSF = 1. The mainte-nance plan for a lighting installa-tion must also specify the optimallamp replacement frequency. Thisdepends on the degree of use of the lamp and is determined byanalysing the period of illumina-tion and the mean service life of the specific lamps.



408

EN = V . n . Ï . æR . æLBa . b

n = . En . a . bÏ . æR . æLB

1 V

EN (lx) Nominal illuminance

n Number of luminaires

a (m) Length of space

b (m) Width of spaceÏ (m) Luminous flux per luminaire

hR Utilance

hLB Light output ratio

V Light loss factor


The UGR method (Unified GlareRating) is an international indexpresented by CIE in publication117 and is used to evaluate andlimit the psychological direct

glare from luminaires. Contraryto previous methods where theglare was rated using the lumi-nance values of a single lumi-naire, this method calculatesthe glare of the entire lightinginstallation at a defined observerposition. According to DIN EN12464, the UGR reference valueis provided for a standard room.An exact calculation of the UGRvalue at a defined observer posi-tion in a room is possible withmodern lighting design programs.The lower the UGR value, thelower the glare. Where the lumi-nance is < 1000 cd/m2, additional

data is provided on the elevationangle, either 65°, 75° or 85°. Thisis the critical angle above whichthe luminaire has an all-roundluminance of 1000 cd/m2.


UGR method

The utilisation factor method isused for an estimated calcula-

tion of lighting installations. It isused to calculate the number of luminaires required for the targetilluminance on the working planeor the illuminance achieved by aspecified number of luminaires.The utilisation factor method isbased on the fact that the aver-age horizontal illuminance for aroom of a specific size can be cal-culated using the total luminousflux of the installed luminairesand the light output ratio alongwith the utilisation factor.The utilisation factor method israrely relevant to routine plan-ning any more since it is based

on standardised rooms. Today,it is much easier and quicker tocalculate individual rooms usingcomputer programs. The utilisa-

Utilisation factor method

Utilisation factor method: formulafor calculating the nominal illumi-

nance EN for a given number of luminaires or the number of lumi-naires n for a given illuminance

tion factor method is still usedas the basis for the relevant Euro-

pean standard and for planningprograms, to calculate the aver-age illuminance for rooms onregular luminaire grids..



409

K = K' + K''

K' = n (p . K1 + R)

K'' = n . tB (a . P + )K2

tLa

K = n [p . K1 + R + tB (a . P + )]K2

tLa

t = Kl (new)K'' (old) – K'' (new)

a (EU/kWh) Energy costs

K (EU/a) Annual costs for alighting installation

K' (EU/a) Fixed annual costs

K" (EU/a) Annual operating costs

K1 (EU) Costs per luminaire incl. mountingK2 (EU) Costs per lamp

incl. lamp replacement

K l (EU) Investment costs (n· K1)

n Number of luminaires

p (1/a) Interest payments for the installa-tion (0.1–0.15)

P (kW) Wattage per luminaire

R (EU/a) Annual cleaning costsper luminaire

t (a) Pay-back time

tB (h) Annual operating time

tLa (h) Service life of a lamp


The cost of a lighting installa-tion is divided into fixed andflexible costs. The fixed costs areunrelated to the operating timeof the lighting installation and

comprise the annual costs for theluminaires, their installation andtheir cleaning. The flexible costs,on the other hand, depend on theoperating time and include theelectricity costs and the materialand labour costs for lamp replace-ment. These values form the basisfor the calculation of a numberof features of the lighting instal-lation. Of particular interest hereare the costs accruing annuallyfor a lighting installation. Often,however, it also makes sense inthe planning phase to comparedifferent types of lamps in termsof their efficiency. Again, these

can be calculated as annual costsor as costs for the production of a specific quantity of light. Whenplanning a new installation andspecifically when improving anexisting, lighting installation, it ishelpful to calculate the pay-backtime, i.e. the period required forthe operating costs savings tooffset the investment costs of the new installation.


Lighting costs




The lighting design processrequires detailed informationto ensure compliance with thestandards relating to illuminancesand visual comfort. Thus for thesimulation programs, luminairemanufacturers provide files thatcontain data on the lightingtechnology of the luminaires.


Planning data

Light simulation Maintained value




For the light simulation, designersuse data on three-dimensionallight intensity distribution andgeometry to determine the illumi-nances and the luminance levels.They also use them to evaluatethe visual impression of a lumi-naire in the room.

E GuideSimulation and calculation | Planning data

Light simulation

IES / Eulumdat DXF i-drop




IES / Eulumdat The IES data format is an inter-nationally accepted data formatused to describe the light distri-bution of luminaires. It can beused in numerous lighting design,

calculation and simulation pro-grams. Originally, the formatwas the standard of the IESNA(Illuminating Engineering Societyof North America). The currentversion is IES LM-63-02.Eulumdat is the European lumendata format as the equivalent of the IES.

E

DXF The DXF format stores the

geometry of a luminaire; thematerials and light distributionare not saved in this exchangeformat. This data format can beimported into most CAD systems.DXF data with 2D elements areused in the planning process toenter the luminaires on the ceil-ing plan. DXF data with 3D ele-ments give an accurate impres-sion of the luminaires in spatialrepresentations.

GuideSimulation and calculation | Planning data

Light simulation

i-drop i-drop is a technology providedby the software manufacturerAutodesk. Using the ”drag & drop”function, it enables contents tobe imported from the Internetinto the software application.For the light simulation, virtualluminaires can be downloadedwith the relevant photometricdata directly from the websiteof the luminaire manufacturerand included in the simulationprogram. The data comprisethe 3D geometry, photometryand textures. A luminaire canbe ”dropped” directly into therequired position in the lightsimulation scene. To align theluminaire automatically withthe room surfaces or any surfacenormal, the ”autogrid” functionneeds to have been previouslyactivated. Using inverse kinemat-

ics, the luminaire is aligned withthe target of the light source.i-drop works with programsincluding VIZ 4 VIZrender, 3dsMax 5 and 6, AutoCAD, and

DIALux. System requirement isthe Microsoft Internet Explorerand activation of the Active Xfunctions.





Maintained value

The maintained value of a lightinginstallation is calculated using thelight output ratio and the lumi-naire maintenance factor speci-fied for the luminaire.

Light output ratio LuminaireMaintenance Factor



414

Cleaning frequency (a)Environmental conditionsA Open luminairesB Open-top reflectorsC Closed-top reflectorsD Closed reflectorsE Dustproof luminairesF Luminaires with indirect emission

1 2 3P C N D P C N D P C N D

0.96 0.93 0.89 0.83 0.93 0.89 0.84 0.78 0.91 0.85 0.79 0.730.96 0.90 0.86 0.83 0.89 0.84 0.80 0.75 0.84 0.79 0.74 0.680.94 0.89 0.81 0.72 0.88 0.80 0.69 0.59 0.84 0.74 0.61 0.520.94 0.88 0.82 0.77 0.89 0.83 0.77 0.71 0.85 0.79 0.73 0.650.98 0.94 0.90 0.86 0.95 0.91 0.86 0.81 0.94 0.90 0.84 0.790.91 0.86 0.81 0.74 0.86 0.77 0.66 0.57 0.80 0.70 0.55 0.45



Maintained value

Light output ratio According to DIN/EN 13032/2,the LOR (Light Output Ratio)describes the ratio of the lumi-nous flux of the luminaire tothe lumens of the lamps used.

Luminaires with direct/indirectemission also specify the ”DLOR”(Downward Light Output Ratio)and the ”ULOR” (Upward LightOutput Ratio) as separate com-ponents. These indicate the lightintensity distribution of a lumi-naire in the lower and upperparts of the room.

Luminaire Maintenance Factor The luminaire maintenance factorLMF takes into account the reduc-tion of luminous flux due to thespoiling of the luminaire. It signi-fies the ratio of a luminaire’s lightoutput ratios before and aftercleaning. The LMF depends on theversion of the luminaire and therelated possibility of soiling. Theluminaires are classified by their”maintenance factor according

to CIE”.




These planning examples illustratewhy light simulations are usefultools in the planning process.Along with the representationof optimised luminaire arrange-ment, the visualisations also helpcommunicate the design concept.At the same time, the examplesgive an account of a historicaldevelopment – from the first useof virtual luminaires to reflector

calculations to the representationof dynamic, coloured lightingconcepts.


Planning examples

Simulation Virtual prototyping




This selection of projects providesinsight into the use of simula-tions for monuments, religiousand administrative buildings andsales rooms.

E GuideSimulation and calculation | Planning examples

Simulation

Chiesa Dives inMisericordia

Brandenburg Gate Ara Pacis

Scottish Parliament BMW Mini dealership Film: Tune the light




Simulation The lighting design of the ChiesaDives in Misericordia in 1998constitutes a milestone in thatthis is the first time that virtualluminaires from ERCO were used

for light simulation. This made itpossible to show, check and ana-lyse concept variants at an earlyplanning stage. Approximately160 virtual luminaires were usedin the model of the church. Theindividual images from the Light-scape program were combinedwith interactive modules, whichwere accessible to all designersvia the Internet and allowedthem to evaluate the variouslight scenes.

E

Planning The lighting concept uses direct,directional light to zone thesanctuary area and to accentu-ate the main focal points such

as pulpit and crucifix. To do this,spotlights were fixed to the steelconstruction of the skylight. Theother component of the conceptconsists of the uniform illumina-tion of the interior of the archedconcrete shell with spotlightsand floodlights fitted above theskylights.

Architect:Richard Meier, New York

Lighting design:Fisher Marantz Stone, New York

Place:Rom

GuideSimulation and calculation | Planning examples | Simulation

Chiesa Dives in Misericordia




E GuideSimulation and calculation | Planning examples | Simulation

Brandenburg Gate

Simulation The Brandenburg Gate, the sym-bol of Berlin, has been restoredand given a lighting makeover.The lighting designers intensivelyused light simulations throughout

the entire planning process. Triallighting was not possible as thebuilding was covered throughoutthe design phase through to theunveiling. Virtual luminaires withtheir photometric light distribu-tion enabled both qualitativeconclusions and quantitativeanalyses. The results were usedto determine the arrangementand alignment of the luminaires.The intensive use of simulationsfor the competitive tender wasa crucial factor in the success of the project.

Planning The columns are accentuated byin-ground lens wallwashers. Thewall surfaces of the passages areilluminated by floodlights with

an asymmetrical light distribu-tion. In the main, the spotlightsfor the Quadriga monument ontop of the gate were discreetlypositioned on adjacent buildings.

Architect:Carl Gotthard Langhans(1732-1808)

Lighting Design:Kardorff Ingenieure, Berlin

Place:Berlin




Simulation For the simulations of the AraPacis, an ancient altar of peace,the designers used the phototexture method. The whole of the temple was photographed

and the photos assigned to theindividual structural parts. TheDIALux program was then usedto provide an exceptionally real-istic impression. One of the focalpoints of the simulation was theanalysis of the ideal angle of incidence for the relief, to checkthe formation of shadows result-ing from the protruding frieze,and to integrate the luminairesperfectly within the architecture.An external view at night wascreated using the photo textureof the travertin wall panels. Themodel was also used for daylightsimulations. The building was

embedded into the environmentin an image processing program.The accessible areas in the build-ing were documented with theirilluminance levels and in the formof Isolux curves.

E

Planning Visitors enter the buildingthrough a closed atrium, beforethe hall with the altar opens upbefore them, bathed in daylight.Spotlights installed in the nichesof the concrete grid ceiling illu-minate the reliefs on the temple.The luminaires fitted with day-light conversion filters corres-pond harmoniously with the lightcolour of the daylight. The warmlight colour of the halogen light,on the other hand, optimallyemphasises the colour of thetravertine wall panels.

Architect:Richard Meier, New York

Lighting design:Fisher Marantz Stone, New York

Place:Rome


Ara Pacis




Simulation The Scottish Parliament with itsasymmetrically vaulted ceilings,its visible roof supporting struc-ture and its seating arrangementfor the Parliament has a complex

geometry that complicated thelighting design. This situationrequired the use of light simula-tions to ensure compliance withthe specifications relating to thedirection of light and the illumi-nance for television broadcasts.Due to the fact that the varyingdistances between luminaire andarea to be illuminated resulted insubstantial brightness contrasts,the illuminance was calculatedon the basis of the faces at theconference table and increased,where necessary, by additionalluminaires. The “Autodesk 3dsMax” program enabled the use

of virtual luminaires with 3Dgeometries and photometric datarecords, which also allowed thedesigners to check the size of the luminaires in the room.For the execution phase, a sepa-rate application was developedto translate the 3D data on the900 luminaires of the simulationinto 2D drawings and provide theluminous flux, position, alignmentand view of each luminaire.


Scottish Parliament

Ground plan

3D model

Study for luminaire arrangement

Analysis of illuminance

Application for the analysis of illuminance

Test Rendering




Planning In the plenary chamber, the highilluminance level required forTV broadcasts is achieved using200 spotlights with Vario-lensesfor 150W HIT-CE with 4200K,

which also ensure visual comfortfor the parliamentarians. The Vario-lenses enable the light-ing designer to adjust the beamangles individually to suit thedifferent distances to the illu-minated areas.

Architects:EMBT Enric Miralles, BenedettaTagliabue, Barcelona; RMJM,Edinburgh

Lighting design:Office for Visual Interaction (OVI),New York

Place:Edinburgh

Simulation:Pierre-Félix Breton, Montrealwww.pfbreton.com


Scottish Parliament




Simulation The simulations for the dealer-ship were used, on the one hand,to review the lighting conceptand, on the other, for a realisticpresentation of the design to the

client. The scope of the simula-tions included the calculation of illuminance and luminance levelsfor the vehicles, walls and work-spaces to analyse critical lumi-nance contrasts and to evaluatethe avoidance of glare. In contrastto the exclusive use of technicaldrawings with ground plan andsection, the visualisations gavethose involved in the planningprocess a better spatial pictureof the lighting solution.

E

Planning The glare-free general lightingof the showroom is provided bypendant downlights for 150WHIT-CE metal halide lamps. Addi-tional spotlights on suspendedlight structures emphasise thepresentation areas. A row of uplights accentuates the shapeof the building and illuminatesthe cantilevered aluminium roof structure.

Architect:Scaramuzza/Rubelli

Lighting designer:Piero Comparotto, Arkilux, Verona

Place:Brescia


BMW Mini dealership




Simulation The simulation of dynamic, col-oured light is extremely complexas seen when moving througha space. In a film, the individualimages can differ both in light

and perspective. To ensure maxi-mum flexibility in the design,the luminaire groups were calcu-lated separately without settingthe final light colour. The videoprocessing program was thenused to put together the films of the different luminaire groupsand to combine the dynamic col-our settings. In this way, the col-ours could be adjusted withoutrequiring new calculations forthe film.

E

Planning In the function room, the indi-vidual tables are accentuatedby narrow-beam spotlights togive them the impression of them being islands. Floodlightswith variable light colours alterthe atmosphere through colourchanges, while the projectionof gobos creates eye-catchingpatterns of light.

Simulation:Aksel Karcher, Berlinwww.akselkarcher.com


Film: Tune the light




In luminaire development, virtualprototyping is used at an earlystage in the design process. Itis used to analyse aesthetic andtechnical aspects such as lightingtechnology, static and thermalcalculations. This is done throughsimulation without the actualluminaire being available. Thismethod accelerates the develop-ment process and supports deci-

sions on design alternatives.

E GuideSimulation and calculation | Planning examples

Virtual prototyping

Luminaires Reflector




E GuideSimulation and calculation | Planning examples | Virtual prototyping

Luminaires

Simulation To relate the form and aestheticsof the design of a luminaire toexisting product photos, a modelof the luminaire is simulated in avirtual photo studio. The actual

lighting situation of the photostudio is transferred to the soft-ware by making a digital imageof the photo studio in HDR for-mat. With a mirror ball taking theplace of the luminaire to be rep-resented, the photographer takesa series of photos with differentexposure times. In the appropriateimage processing program, thisseries is then used to calculatea High Dynamic Range Image(HDRI). HDRI covers a far greaterrange of luminance contraststhan conventional digital photos.The HDR image is imported as anenvironment into which the sim-

ulation program provides infor-mation on beam direction, lightcolours, relative luminances, typesof shadow and reflections, as willexist in an actual photo studio.

Luminaire design: ERCO

Simulation: ERCO; Aksel Karcher,Berlin




E GuideSimulation and calculation | Planning examples | Virtual prototyping

Reflector

Simulation The simulation of reflectors pro-vides very precise information onlight distribution intensities in avery short time, without havingto use expensive tools to produce

prototype reflectors. For the reflec-tor simulation, the lamps to beused are initially measured accu-rately and the individual compo-nents of the lamp designated toluminances and other lightingcharacteristics. Subsequently, thegeometry of the light apertureand the lamp position are defined.Starting from a basic reflectorform, the designer then changesthe contour of the reflector stepby step to achieve the requiredlight distribution. After eachchange of contour, the programcalculates the illuminance for asample area to enable an assess-

ment of the light distribution,and produces a light intensitydistribution curve of the virtualluminaire. Programs for reflectorsimulation are usually based onthe (forward) ray tracing method,where the rays of light are emit-ted from the lamp.

Definition of lamp properties

Rendering Lamp

Reflector simulation

Light distribution on test surface

Light distribution curve




AAbsorptionThe ability o substances to

neither reect nor transmit light.Its dimension is the absorptionratio, which is defned as the ratioo absorbed → luminous ux toincident luminous ux.

Accent lightingEmphasis given to individualareas o a space or to individualobjects by specifc lighting at alevel above that o the ambientlighting.

AccommodationAdaptation o the → eye to ena-

ble objects at dierent distancesto be seen in sharp ocus. It isperormed by deorming the eyelens.

AdaptationThe ability o the eye to adjustto the → luminances in the feldo vision. Perormed initially viathe dilation or contraction o thepupils, though a ar greater scopeis achieved by altering the sensi-tivity o the retina’s receptor cellsand by changing between visionwith cone cells and vision withrod cells (see also → Eye).

AdapterA device or connecting a lumi-naire, especially a → spotlight or→ oodlight, both mechanicallyand electrically to a → track.

Additive colour mixingReers to the mixing o coloursby the addition o spectral ranges.According to the trichromatictheory, the colours produced byadditive colour mixing are thecomplementary colours o theprimary colours (red, green andblue). Mixing the three primarycolours in equal amounts pro-duces white light.

Ambient lightingUniorm lighting o an entirespace without giving specialconsideration to individual visualtasks.

Ambient luminescenceAmbient luminescence providesgeneral lighting or the surround-ing area. It ensures that architec-

ture and the objects and peoplein it are visible. It allows the occu-pants simply to get their bearings,work and communicate.

E GuideGlossary

Angle o visionThe subtended angle within whichan object is perceived; the meas-urement o the size o the imageo an object on the retina.

Anti-dazzle capAn anti-dazzle attachment orcontrolling the glare o the directcomponent o light rom the→ lamp in the beam directiono the → luminaire. The → beamis restricted in the main directiono the beam and the spill lightcomponents are reduced and/orprevented completely.

Anti-dazzle protection→ Solar protection

Anti-dazzle screenAnti-dazzle attachment toimprove → visual comort. Thecross bae partially conceals thereector and the lamp.

Architectural lightingTerm given to lighting conceptsusing both → daylight and arti-fcial light, whereby the technicalsolution is an integral constituentpart o the architecture.

BBacklightingType o lighting which is projected rom behind the objectand casts shadows orward. Itcan result in a halo o light beingvisible around the object. In stagelighting, backlighting is used ordramatic lighting eects.

Barn doorsTerm given to anti-dazzle platesarranged in a square around theluminaire to reduce the directglare; typically ound on stagelighting projectors.

Beam angle→ Emission angle

BrillianceLighting eect on reective sur-aces or transparent materials.Brilliance is produced by thereection o the light source orthe reraction o light; it requiresdirected light rom point lightsources.

CCandela, cdUnit o → light intensity; un-

damental dimension o lightingengineering. 1cd is defned asthe light intensity emitted by amonochromatic light source witha radiant power o 1/683W at555nm.

CCGAbbreviation or conventional→ control gear.

Ceiling washlightLuminaire type which is mountedindividually or in rows aboveeye-level in or on walls. These

luminaires illuminate the ceilingarea uniormly and without caus-ing glare; they are predominantlydesigned or → tungsten halogenlamps, → uorescent lamps or→ high-pressure discharge lamps.

Ceramic discharge tubesDischarge tube o → a high-pressure discharge lamp. Ceramicdischarge tube technology oersbetter colour stability and higher→ luminous efcacy than quartztechnology.

Chromaticity diagramSystem or the numerical clas-sifcation o → colours o lightand body colours. The chromatic-ity diagram is a two-dimensionaldiagram in which the colour locio all colours and colour mixesare represented in grades o saturation ranging rom the purecolour through to white, whichcan be numerically expressed bytheir xy coordinates. Colour mixesare located on a straight linedrawn between the colours tobe mixed; the → colour o lighto → thermal radiators lies onthe defned curvature o thePlanckian curve.

Colour adaptationThe ability o the eye to adapt tothe → colour o light in the sur-roundings. Results in the percep-tion o relatively natural colourunder dierent colours o light.

Colour compensationProcedure in lighting engineeringor correcting the → colours o light rom several luminaires withRGB colour mixing in order to

ensure that lighting tasks have auniorm colour impression.

Colour lter→ Filter

Colour mixing

In lighting engineering, additivecolour mixing using red, greenand blue can be used to obtainmixed colours. The combinationo all three primary colours pro-duces white light. Subtractivecolour mixing starts with the pri-mary colours o cyan, yellow andmagenta and flters out particularspectral components.

Colour o lightThe colour o the light emitted bya → lamp. The colour o light canbe expressed by using xy coordi-nates to speciy a colour locus

in the → chromaticity diagram.White light colours can also beexpressed as a → colour temper-ature, and can also be broadlycategorised as either warm white(ww), neutral white (nw) anddaylight white (tw). The samecolours o light can have dierentspectral distributions and a cor-respondingly dierent → colourrendition.

Colour renditionQuality o colours as they occurunder a given light source. Thedegree o colour deviation rom areerence light source is given bythe colour rendition index Ra.

Colour rendition indexThe degree o colour distortionunder a given light source incomparison with a reerencelight source. The optimum colourrendition index is Ra = 100.

Colour saturationMeasure or the intensity o a colour between the purecolour and the white point in

the→

chromaticity diagram.Together with hue and bright-ness, this is one o the threeundamental properties o a col-our. Colour saturation is usuallygiven as a percentage.

Colour temperatureDescribes the → colour o lighto a light source. With → thermalradiators, this is virtually the sameas the actual temperature o thelamp flament in degrees Kelvin (K).For → discharge lamps, the colourtemperature that is most similaris given. This is the temperature at

which a→

thermal radiator emitslight o a comparable colour.




E GuideGlossary

Compact fuorescent lampThese are → uorescent lampswith particularly compact dimen-sions achieved by bending ortwisting the discharge tube

and/or by combining severalshort discharge tubes. Compactuorescent lamps have only onelamp cap.

Compact projectorSpotlight with optical systems orthe projection o → gobos andtext templates (patterned flters)or use with various lamp types.Depending on the optical system,a distinction is drawn between acondenser projector and an ellip-soid projector.

Condenser projector→ Compact projector

Cone→ Eye

Cone vision→ Photopic vision

Connected loadThe connected load is the totalsum o the nominal wattages o electric loads.

Connected load o the lightingThe maximum power o the entirelighting installation, regardless o the actual energy consumption.

ConstancyThe ability o visual perception todiscern eatures o objects (size,shape, reectance, colour) despitechanges in the environment(distance, position, lighting). Con-stancy is absolutely vital in orderto create a structured image o reality out o the ever-changingpatterns o luminance on theretina.

ContrastThe dierence in the → lumi-nance or colour o two objectsor o one object and its surround-ings. The visual task becomesincreasingly difcult as the con-trast decreases.

Contrast renditionCriterion or limiting reectedglare. The contrast rendition isexpressed by the contrast rendition

actor (CRF). It is defned as theratio between the luminance con-trast o a visual task under the givenlighting and the luminance con-trast under the reerence lighting.

Control gearThese devices are necessary or theoperation o certain light sources.They primarily reer to current-limiting control gear (chokes)

and → starters, i.e. → ignitorsrequired to operate → dischargelamps but also to → transormersrequired to operate → low-voltagehalogen lamps. Inductive controlgear devices are available eitherin conventional (CCG) or low-lossversions (LCG). They sometimesrequire an additional ignitor orstarter. Electronic control gear(ECG) work without any additionalignitor and prevent annoyingtransormer hum or → strobo-scopic eects.

Coolbeam→ Coolbeam reector

Coolbeam refectorDichroic reector which pre-dominantly reects visible light,but transmits (glass reectors) orabsorbs (metal reectors) inraredradiation. Coolbeam reectorsresult in a lower thermal load onthe illuminated objects. Coolbeamreectors are also known as multi-mirror reectors.

Cover glassThe protective layer o a → lumi-naire through which the light isemitted. Depending on the light-ing technology, a luminaire canhave one or more such layers.The apparent → luminance o thecover glass is used when evaluat-ing the glare o a luminaire.

DDALIAbbreviation or → DigitalAddressable Lighting Interace.

Dark SkyTerm used in lighting design orlighting which avoids → lightpollution in the outdoor area inorder to prevent brightening thenight sky.

Dark Sky technologyReector technology whichresults in no light being emittedabove the luminaire in order toavoid → light pollution.

Darklight technologyReector technology whichresults in the observer not beingsubjected to glare as long as thelamp remains above the cut-o

angle. The → lamp cut-o angleand the reector’s → luminairecut-o angle are identical. Dark-light technology oers optimumefciency or maximum → visual

comort.

Day vision→ Photopic vision

DaylightDaylight includes the directed,direct sunlight, the ambient lighto the sky and the diuse lightrom the clouds. The → illumi-nances o daylight are ar higherthan the illuminances o artifciallighting.

Daylight actorRatio between the → illuminanceproduced by → daylight on theworking plane o a room and theexterior illuminance; the daylightactor can be measured in the→ daylight simulator.

Daylight simulatorTechnical equipment used tosimulate sunlight and daylight.→ Daylight can either be simu-lated by the hemisphericalarrangement o numerous lumi-naires or by the multiple reec-tion o a luminous ceiling in aroom ftted with mirrors. Sunlightis simulated by a parabolic mirrorwhose movement can reproducethe sun’s path during the day orthe year or any latitude. A daylightsimulator allows the relationshipbetween light and shadow in pro-posed buildings to be simulatedon a model, including testing thevarious lighting control elementsand measuring the → daylightactors on the model.

Daylight systemsTechnical measures based on→

reection and→

reractionin the area o windows and sky-lights which are used to improvethe provision o → daylight in aroom and, in this way, to reducethe electrical power consumption.

Daylight white, dw→ Colour o light

Dichroic refector→ Coolbeam reector

Diuse light

Diuse light is emitted romlarge, luminous suraces. It pro-duces a sot, uniorm lighting withlow →modelling and → brilliance.

DiuserOptical element or dispersing therays o light in order to give a sot→ beam. Fitted to the luminaire,the diuser reduces the lamp

luminance and can reduce glare.

Digital Addressable LightingInteraceDigital control protocol or→ lighting control withinarchitecture. The system enablesluminaires to be individuallycontrolled and can be integratedinto building control systems as asubordinate, stand-alone system.

DimmerControl device to infnitely varythe → luminous ux o a lamp

using leading-edge phase control.Can be used with → incandescentlamps, → low-voltage halogenlamps and → uorescent lamps.Although, it is technically possibleto dim → high-pressure dischargelamps, it is neither complete norcommon.

Direct illuminanceThe lighting emitted directlyrom luminaires onto the workingplane, e.g. by downlights.

Directed lightDirected light is emitted rom→ point light sources. One spe-cifc direction o light predomi-nates and this provides goodeects in terms o → modellingand brilliance. Even unmodifedbeams rom open, point lightsources produce directed light,in which case, however, sincethe main direction o the beamis spread with varying intensityin all directions, the commonpractice is to ocus the light intoa uniormly directed → beamusing → light guidance.

Directional luminaireUsually a recessed luminairewhich has a beam angle withina defned angular range (rota-tion and tilt) that can be reelyselected. Suitable or retail and→ exhibition areas.

Directive luminaireTheir design invariably complieswith standardised directiveluminaires and saety signs; theinscriptions and signs are backlit.

Discharge lampLamp in which the light is pro-duced by electrical dischargethrough gases or metal vapours.A distinction is drawn between




E GuideGlossary

low-pressure and high-pressuredischarge lamps. Low-pressuredischarge lamps include conven-tional → uorescent lamps and→ compact uorescent lamps.

Their light is produced by excitingthe uorescent substances withradiation. High-pressure dischargelamps include → mercury vapourlamps, → metal halide lamps and→ high-pressure sodium vapourlamps. Their light spectrum is dueto their unique composition andhigh operating pressure.

DMXAbbreviation or Digital Multi-plexed. The digital control pro-tocol is most oten used or→ lighting control with theatricalstage lighting.

Dominant wavelengthMeasurement parameter or iden-tiying a mixture o colours byone wavelength. In the → chro-maticity diagram, the dominantwavelength can be calculatedby extrapolating a line rom thewhite point through the givencolour locus to meet the spectralcolour line. The opposite is thecomplementary wavelength. Thedominant wavelength has varioususes including colour classifca-tion o → LEDs.

Double washlightA luminaire used in corridorsand hallways to provide uniormillumination o the parallel wallsand the oor area.

Double-ocus downlightDownlight with elliptical reectorsystem and Darklight reector. Itprovides maximum luminous uxrom the smallest ceiling aperture.

Double-ocus wallwasherA luminaire used to provideuniorm illumination o walls.The optical system ocuses thelight into a second ocal pointand only emits reected light. Thisallows the lamp to be completelyshielded or improved → visualcomort.

DownlightA compact luminaire with a roundor square opening. Downlights aredesigned or mounting in or onceilings or or suspended mount-ing. Their light is predominantly,but not exclusively, directed

downwards onto horizontalsuraces.

EECGAbbreviation or Electronic→

Control Gear.

Electronic control gear→ Control gear

Ellipsoid projector→ Compact projector

Elliptical refector→ Reector

Emergency lightingTerm used to describe the lighting

o emergency exits and escaperoutes using emergency lightingluminaires and also to describethe identifcation o emergencyexits using illuminated saetysigns or directive luminaires.

Emission angleThe angle between the points o a → light intensity distributioncurve at which the → light inten-sity drops to 50% o the valuemeasured in the main beam direc-tion. The emission angle deter-mines the light beam diameter.

EthernetData network technology orlocal networks which permits theexchange o data between alldevices connected to a local areanetwork (→ LAN).

EULUMDATEuropean Lumen Data ormat thatdescribes the → light intensitydistribution o luminaires.

Exhibition lightingA type o lighting designed to addvisual emphasis to exhibits; it cancover a wide area or be accentu-ated. In the area o museums andgalleries, → light protection playsan important role.

EyeThe eye is an optical system con-taining the cornea and a deorm-able lens, which project the imageo the outside world onto theretina, as well as the iris whichbroadly regulates the amount o the incident light by adjustingthe pupil opening. In the retina,

the incoming photostimuli areconverted into neuron impulsesby receptor cells. The eye has twosystems o photoreceptors: therod cells and the cone cells. The

rods are distributed relativelyuniormly across the retina; theyare highly sensitive to light andenable wide-angle vision underlow → illuminances (→ scotopic

vision). Their visual acuity islow, however, and colours arenot perceived. The cones, on theother hand, are predominantlyconcentrated in the ovea, a smalldepression in the retina locatedon the optical axis or visual axis.The cones enable sharp, colouredvision within a limited angle o vision, but require high illumi-nances (→ photopic vision).

FFaceted refectorReector with at acets whichproduces a more cohesive → beamthan conventional, mirror-fnish→ reectors.

FadingTransition between → light scenes.Fading in reers to the starting-upo a light scene, while ading outreers to the ending o a lightscene.

Fading timeThe duration o the light scenetransition is known as the adingtime.

Fill lightType o lighting which discreetlybrightens an object, a setting or ashadow using a sot light withoutthe observer being consciouslyaware o it. The fll light comple-ments the → key light.

FilterOptical elements with selective→ transmission. Filters only trans-mit part o the incident radiation,to produce either coloured lightor by fltering out invisible radia-tion such as ultraviolet or inra-red. Filter eects can be achievedby → absorption (absorptionflter) or → reection (reectionflter). Intererence flters are e-ective reection flters that workusing special vaporised coatings;they are also known as dichroicflters.

FloodCommon term or wide-beam→ reectors or → reector lamps.

FloodlightLuminaire with a wide beamangle that can be directed at any

point by rotating and tilting; usedmainly with → track.

Floor washlight

Luminaire type which is fttedeither individually or in rows atlow level in or on the wall. Theseluminaires illuminate the oorarea uniormly and without creat-ing glare.

FluorescenceFluorescence is a process in whichsubstances are excited by meanso radiation to produce light; thewavelength o the emitted lightis always higher than the wave-length o the incident radiation.One o the primary technicalapplications o luorescence

is in luorescent lamps where→ ultraviolet radiation is con-verted into visible light.

Fluorescent lampA tubular low-pressure dischargelamp containing mercury vapour.The → ultraviolet radiation pro-duced by the mercury dischargeis converted into visible lightby uorescent substances onthe internal surace o the tube.Dierent colours o light and→ colour rendition qualitiescan be obtained by combiningdierent uorescent substances.The uorescent lamp usuallyhas heated electrodes enablingit to be started with relativelylow voltages. Fluorescent lampsrequire conventional or electronic→ control gear.

Focal glowFocal glow creates accents. Lightis actively involved in conveyinginormation by visually empha-sising areas o signifcance anddiminishing the less importantareas.

Fovea→ Eye

Fresnel lensStepped lens where the lens eectis achieved by the concentricarrangement o lens segments.Fresnel lenses are used or stagespotlights and spotlights withadjustable → beam angle.

GGatewayA data exchange protocol thatenables communication o dier-ent protocols in a network.




E GuideGlossary

General service lamp→ Incandescent lamp

Glare

Collective term or the reductiono → visual perormance or theimpairment o perception due tohigh → luminances or luminancecontrasts in the visual surround-ings. A distinction is made betweendiscomort glare and disabilityglare: the ormer concerns anobjective reduction in vision andthe latter a subjective impairmentdue to any disparity between the→ luminance and inormationcontent o the observed area. Theglare can be caused by the lampitsel (direct glare) or by → reec-tion o the lamp (reected glare).

Global illuminationIn three-dimensional computergraphics, a calculation used todescribe the simulation o allways in which light rays mayradiate.

Global radiationThe sum o solar radiation andsurrounding sky radiation.

GoboCommon term in spotlight illumi-nation (originally rom stage light-ing) or a mask or image template(patterned flter) used to createeects and project images usinga projecting optical system.

Grazing lightType o lighting where the light isincident to the surace at a veryshallow angle. Used to emphasisesurace structure and texture.

HHDRAbbreviation or → High DynamicRange

High Dynamic RangeDescribes a very high contrastrelationship in a digital image.Images in HDR ormat can storea higher luminance contrast thanLow Dynamic Range with 255gradations.

High-pressure discharge lampsThis category includes → mercury

vapour lamps,→

metal halidelamps and → high-pressuresodium vapour lamps.

High-pressure sodium vapourlampHigh-pressure → discharge lampscontaining sodium vapour. Becausethe sodium vapour is aggressive

at high pressures and woulddestroy glass, the inner dischargetube consists o aluminium-oxideceramic, enclosed in the externalglass envelope. The → colour o light produced is in the warmwhite range. High-pressure sodiumvapour lamps require → ignitorsand → control gear.

Honeycomb anti-dazzle screenAnti-dazzle attachment withhoneycomb structure used torestrict the → light beam andreduce → glare.

Hotel lightingHotels are public areas with partic-ularly stringent demands on thequality o the lighting design.Hotel lighting includes archi-tecturally-oriented lighting inentrance areas, atmosphericmood lighting in the restaurantareas, multiunctional lightingin conerence centres, economi-cal lighting in the thorougharesand corridors, and private lightingatmospheres in the hotel rooms.

Hub

Node or connecting networksegments or hubs, or examplevia → Ethernet.

IIESInternational data ormat ordescribing the light intensitydistribution o luminaires.

IgnitorA component in control gearthat acilitates the ignition o → discharge lamps by producingvoltage peaks.

Incandescent lamp→ Thermal radiator where lightis created by heating a Tungstenflament. The incandescent fla-ment is enclosed in a glass bulbflled with an inert gas such asnitrogen which prevents it romoxidising and delays the vapori-sation o the flament material.Incandescent lamps are availablein numerous orms, the main

groups being general servicelamps with pear-shaped, clearor rosted bulbs, → reectorlamps with a variety o internalreective coatings and PAR lamps

made o moulded glass withintegral parabolic reector.

Individual workplace lighting

In contrast to → ambient light-ing, this lighting is designed orone specifc workplace, e.g. using→ task lights.

ILCOSAbbreviation or InternationalLamp Coding System. It is a uni-orm → lamp designation system.

IlluminanceThe illuminance, measured inthe units o lux (lx), is the ratiobetween the luminous ux inci-dent upon an area and the size

o that area.

Indirect lightingLighting which is emitted rom theluminaires and indirectly reectedonto the working plane via reec-tive suraces, e.g. → uplights.

Inrared radiationInvisible thermal radiation inthe wavelength range > 780 nm.Inrared radiation is producedby all light sources, but especiallyby → thermal radiators, where itconstitutes the majority o theemitted radiation.

In-ground luminaire→ Recessed oor luminaire

IntererencePhysical phenomenon producedwhen waves that are out o phaseare superimposed; it can resultin selective weakening o theintensity o various wavelengths.Intererence is used in → fltersand → reectors or selective→ transmission or → reection,

respectively.

Intererence lter→ Filter

Iso-luminance contour diagramDiagram representing luminancedistributions, where a single reer-ence plane is shown with con-tours superimposed o the sameluminance.

Isolux diagramDiagram representing illuminance

distributions, where a single reer-ence plane is shown with con-tours superimposed.

KKey lightType o lighting using → accent

light to considerably improve theappearance o an object or set-ting. To avoid harsh contrast, a→ fll light is used.

KNXAbbreviation or Konnex. Stand-ardised digital system or buildingcontrol, e.g. or lighting, heatingand ventilation.

LLambert’s Cosine LawLaw which states that the→ illuminance is a unction o the distance rom the light source.The illuminance is inversely pro-portional to the square o thedistance.

LampElectric light source such as an→ incandescent lamp, → dis-charge lamp or → LEDs. In a→ luminaire, the light sourceproduces light which can thenbe directed to the target objectsvia → reectors.

Lamp capComponent o the → lampthrough which the electricalconnection to the → lampholdero the → luminaire is made.

Lamp cut-o angleWith → downlights, this is theangle subtended between thehorizontal plane and a straightline extended rom the edge o the luminaire to the edge o lamp.It is a dimension or the → visualcomort o a luminaire in additionto the → luminaire cut-o angle.

Lamp designation systemUniorm system or namingelectric lamps. The abbreviationo a lamp includes inormationon the method o light generation,the bulb material or gas fllings,the wattage and the type o lampholder.

Lamp lieThe unctional lie o a lamp. Theunctional lie o incandescent

lamps is based on the ailure o 50% o the lamps. The unctionallie o discharge lamps and LEDsis calculated at the point whenthe installation’s luminous ux




E GuideGlossary

drops to 50% due to ailed lampsand reduced luminous ux.

Lamp lumens maintenance

actorCalculation value or the mainte-nance plan o a lighting systemwhich considers the drop in lumi-nous ux due to the lamp aging.

Lamp survival actorCalculation value or the mainte-nance plan o a lighting systemwhich considers the deviation inthe lie o individual lamps romthe average lamp lie and/or pre-mature lamp ailures with fxedmaintenance cycles.

LampholderBracket used to hold the lampin a luminaire and to make theelectrical connection. Typicallampholder types are screw-thread, bayonet fxing and bi-pinbase. The type o lampholder oreach lamp is documented in the→ Lamp designation system.

LANAbbreviation or Local AreaNetwork. A permanently installedlocal computer network overshort distances.

LCGAbbreviation or Low-loss→ Control Gear.

Leading edge technologyMethod o dimming in which thepower consumption o the lampsis limited by the leading edge o the alternating current wave.With leading edge technology,the current is switched on witha delay ater the alternating volt-age passes through the zero pointand remains switched on until thenext zero crossing. Dimmers withleading edge technology are notusually suitable or conventionalor compact uorescent lamps.Leading edge technology is usedto control conventional controlgear.

LEDAbbreviation or Light EmittingDiode. An electroluminescentradiator that produces light byrecombining charge-carrier pairsin a semiconductor. LEDs producea narrow-band spectral range.White light is obtained by→

RGB mixing or→

lumines-cence conversion.

LensOptical element used or → lightguidance. The radius, curvatureand surace texture o the lensdetermine its optical properties.

With projector spotlights, lenssystems can be used to preciselyproject images and patterns rom→ gobos. → Fresnel lenses can beftted into spotlights as an acces-sory in order to spread the lighteither symmetrically or asym-metrically.

Lens wallwashersLuminaires with asymmetric lightintensity distribution or uniormwall lighting. The light is spreadby a → lens.

Lie→ Lamp lie

Light beamThe term or a beam o light,usually rom a rotationally sym-metrical reector. The luminaire’soptical system determines whetherthe gradient o the edge o thebeam is abrupt or gradual. Withspotlights, the beam can be reelyaimed by rotating and tilting theluminaire.

Light beam diameterThe diameter o a → light beamresults rom the → emissionangle and the distance to the→ luminaire.

Light astnessThis describes the degree towhich a material will be damagedby exposure to light. It primarilyapplies to changes in the colouro the material (colour astness),but may also apply to the mate-rial itsel.

Light guidanceLight guidance by means o → reectors or → lenses is usedin → luminaires with deinedoptical properties to produceluminaires. Light guidance iscrucial or → visual comort.The → glare o luminaires canbe reduced to a permissible levelby controlled light guidance.

Light guide systemOptical instrument used to guidelight along any route, even aroundcurved paths. The light is chan-nelled along the light guide

system, a solid rod or tubularconductor made o transparentmaterial (glass or synthetic fbres,tubes or rods), which unctionthrough total internal reection.

Light intensityUnit: → candela (cd). The lightintensity is the → luminous uxper solid angle (lm/sr). The spatialdistribution o the light intensity

o a light source is shown by thelight intensity distribution curve.

Light intensity distributioncurveThe light intensity distributioncurve is obtained by taking a sec-tion through the light intensitydistribution, which represents the→ light intensity o a light sourceor all solid angles. With rotation-ally symmetrical light sources,the luminous intensity distribu-tion can be shown by a singlelight intensity distribution curve,whereas two or more curves are

required or axially symmetricallight sources. The light intensitydistribution curve is generallyexpressed in the orm o a polarcoordinate diagram, but withprojectors it is oten shown inCartesian coordinates.

Light loss actorReciprocal value o the mainte-nance actor. When designing aninstallation, this takes the overalllight loss eect o lamp ageing,lamp ailure and general dirtaccumulation into consideration.The new value o illuminance ishigher than the maintenanceactor by an amount equal tothe light loss actor.

Light output ratioThe light output ratio is the ratioo emitted → luminous ux tothe lamp lumens produced in theluminaire. It is abbreviated as LOR.

Light pollutionTerm used or light emissionwhich, due to its → illuminance,its direction or its → spectrum,

causes intererence in anyparticular situation. In outdoorareas, light pollution reers tolight which is emitted into thenight sky reducing the darkness.The consequences include wastedenergy and a detrimental eecton ora and auna. The avoidanceo light pollution is also known as→ Dark Sky in terms o lightingdesign.

Light powerAnother term or → luminousux; in radiation physics, it isequivalent to the → radiant

power.

Light protectionThe limiting o intensity, → ultra-violet radiation and → inraredradiation, required especially inrelation to exhibition lighting.

Light protection is implementedby choosing suitable → lampsand luminaire types and by→ fltering the emitted light.

Light reraction→ Reraction

Light sceneA lighting situation or a lightingmood with a specifc combinationo brightness levels and colours.Light scenes can be saved andthen recalled either automaticallyor manually using a → lighting

control system.

Light sequenceA series o several consecutive→ light scenes. Dynamic sceniclighting is produced by defn-ing the sequential order o lightscenes, their duration and thetransitions between the scenesusing a → lighting control.

Light simulationA calculation o a lighting situ-ation using sotware. The quanti-tative light simulation is used tocheck the design based on numeri-cal values, while the qualitativesimulation is aimed at examiningthe atmosphere and the aesthet-ics o the lighting design.

Light source→ Lamp

Light structureArrangement o individual→ luminaires connected toorm a predominantly linearramework which is usually sus-

pended rom the ceiling.

Lighting controlLighting control enables the light-ing o a space to be adjusted tosuit dierent usage requirementsand environmental conditions.Each situation is represented bya → light scene, with a specifcpattern o switch and dimmersettings or individual circuits. Thelight scene is stored electronicallyand can be recalled at the toucho a button.

Local Operating NetworkBus system or communicationbetween installations and devices,or example, or building controlsystems.




LONAbbreviation or → Local Operat-ing Network

Louvred luminaireCommon term or long rectangu-lar luminaires ftted with → uo-rescent lamps (linear uorescentluminaires), usually designed withlow-brightness louvres.

Low-pressure discharge lampThis category includes conven-tional → uorescent lamps andcompact uorescent lamps.

Low-voltage halogen lampHighly compact → tungsten halo-gen lamps which operate on low

voltage (usually 6, 12 or 24 V).Frequently ftted with an inte-grated metal reector or cool-beam reector.

Lumen, lmUnit o → luminous ux.

LuminaireAn object containing a lampand providing artifcial illumina-tion. The → lamp is held in the→ lampholder. → Reectors pro-vide → light guidance. Luminairescan be permanently installed assurace-mounted, recessed, pen-dant or ree-standing luminairesor track-mounted, which can bevariably positioned and aimed.

Luminaire classicationThe photometric classifcation ismade using the luminous inten-sity distribution curve and lightoutput ratio, and also the type o lamp and maximum lamp power;the saety classifcation is madeusing the → protection mode and→ protection class.

Luminaire cut-o angleAngle below which no direct→ relection o the lamp isvisible within the → reector.With → Darklight reectors theluminaire cut-o angle is identi-cal to the → lamp cut-o angle.

Luminaire maintenance actorA calculation actor determinedby the maintenance plan o alighting installation which con-siders the drop in → luminousux due to the luminaire designand the reduction in luminaire

perormance.

LuminanceUnit: candela/m2 (cd/m2). The lumi-nance describes the brightness o a surace that emits light eitheras a light source or by → trans-

mission or → reection. The lumi-nance is defned as the ratio o → light intensity to the suraceprojected perpendicular to thedirection o observation. Dierentlycoloured suraces with the sameluminance are equally bright.

LuminescenceCollective term or all orms o light not created by thermalradiators (photo-, chemo-, bio-,electro-, cathodo-, thermo- ortriboluminescence).

Luminescence conversionConversion rom one spectrum toanother by using phosphors. Thistechnique is used with → LEDs or→ uorescent lamps to convertultraviolet radiation into visiblelight.

Luminous ecacyUnit: lumen/watt (lm/W). Theluminous efcacy is defned asthe ratio o the emitted → lumi-nous ux to the expended electricpower o a → lamp.

Luminous fuxUnit: lumen (lm). The luminousux expresses the total → lightpower emitted by a light source.It is calculated rom the spectral→ radiant power by evaluatingthis with the spectral brightnesssensitivity o the → eye.

Lux, lxUnit o → illuminance.

MMains voltageThe electrical → voltage suppliedthrough mains power distribution.In most regions o the world themains voltage is 230V at 50Hz.Other supply voltages may requiretransormation equipment.

MaintenanceTerm or the measures taken orthe ongoing and eective opera-tion o a lighting installation. Itincludes replacing lamps, cleaningluminaires and setting the direc-

tion o any→

spotlights. Mainte-nance is taken into considerationin the design o a lighting systemusing the parameter → light lossactor.

Maintenance actor→ Light loss actor

Mercury vapour lamp

High-pressure → discharge lampcontaining mercury vapour. Incontrast to low-pressure dischargewhich creates → ultraviolet lightalmost exclusively, mercury vapouremits visible light under highpressure, but with a low redcontent. The red content can besupplemented and the → colourrendition improved by addingother uorescent substances.

Mesopic visionIntermediate state between→ photopic (day) vision usingthe cone cells and → scotopic

(night) vision using the rod cells.The levels o colour perceptionand → visual acuity take on cor-responding intermediate values.Mesopic vision covers the lumi-nance range rom 3 cd/m2 to0.01 cd/m2.

Metal halide lampHigh-pressure discharge lampflled with metal halides. The largenumber o raw materials availableallows metallic vapour mixturesto be created whose dischargegenerates high → luminousefcacy and good → colourrendition.

ModellingThe accent lighting o three-dimensional shapes and suracetextures using directed light roma point light source. It is generallyexpressed through the improve-ment in shadow quality.

Multiunctional lightingThis is a typical lighting require-ment in → hotels and congresshalls hosting seminars, coner-ences, receptions and entertain-ment. The multiunctional lightingmay be created by using severallighting components which areswitched on separately and addi-tively, oten linked to program-mable → lighting controls.

Multimirror→ Coolbeam reector

Museum lightingA particular branch o → exhibi-tion lighting; it places specialdemands on the design o the

lighting and on the light distribu-tion on the exhibits and archi-tecture and also requires → lightprotection or sensitive exhibits.

NNarrow spotCommon term or very narrow-

beam→

reectors or→

reectorlamps.

Neutral white, nw→ Colour o light

Night vision→ Scotopic vision

Nominal powerThe power or which an electricdevice is designed.

OOce lightingThis is specifcally oriented aboutthe requirements or VDU work-places; see VDU lighting. A distinc-tion is drawn between → ambientlighting, workplace-orientedambient lighting and individual→ workplace lighting.

PPAR lamp→ Incandescent lamp

Parabolic refector→ Reector

Perceptual psychologyA branch o the sciences concernedwith various aspects o perception,in particular neural response andprocessing o sensory stimuli.

Permanent SupplementaryArticial LightingAdditional artifcial lightingespecially in rooms lit only bywindows on one side. PSALIcompensates or the all in illu-minance as the distance romthe window increases.

PhotometerInstrument used to measure photo-metric perormance. The primarydimension is → luminance, otherdimensions are derived rom theilluminance. Photometers areadjusted to the spectral sensitivity

o the→

eye. Special measuringequipment called goniophoto-meters are required or measuringthe → light intensity distributiono luminaires.

E GuideGlossary




Photon mappingAlgorithm used in light simulationwhich is primarily employed asan extension o ray tracing basedprocesses.

Photopic visionAlso: day vision. Vision involving→ adaptation to → luminanceso above 3cd/m2. Photopic visionis perormed by the → cone cellsand is thereore concentratedon the area o the → ovea.The → visual acuity is high andcolours are perceptible.

Pictogram luminairesThe design o pictogram lumi-naires usually matches standarddirective luminaires and saety

signs; pictograms are edge-lit orbacklit.

Planckian radiatorBlack-body radiator. Ideal→ thermal radiator whoseradiation properties are describedby Planck’s Law.

Play o brilliantsPlay o brilliants is a decorativelighting component. The brillianteects can be rom lamps orilluminated materials – rom acandle ame and chandeliers tosculptures o light, they contrib-ute to the atmosphere o prestig-ious and emotive settings.

Point illuminanceIn contrast to the average→ illuminance, the point illumi-nance expresses the illuminanceat a defned point in space.

Point light sourceTerm describing compact, virtuallypoint-orm sources. The light rompoint light sources can be opti-mally directed and ocused.Conversely, linear or area lightsources produce diuse light,which becomes more diuse themore the light disperses.

ProjectionOptical image produced bya two-dimensional mask or a→ gobo on a surace. Luminairesor projection require an opticalimaging system. The ocus can beadjusted using a lens system.

Protection class

Indicates the measures taken toprevent contactable metal partsrom conducting current in caseo a ault occurring.

Protection modeThis indicates the protectionclassifcation o a → luminaire.The combination o two digitsindicates the degree to which the

luminaire is protected againstthe ingress o oreign bodies andwater.

PSALI→ Permanent SupplementaryArtifcial Lighting

RRadiant powerFrom electrical lamps, this is theproduct o converted electrical

energy. Physical unit: watt. Inthe wavelength range between380nm and 780nm, the radiantpower (W) is quantifed as the→ light output (lm).

Radiation intensityThis reers to the radiant powerper square metre o area; themaximum value or daylight isapproximately 1kW/m2.

RadiosityLight simulation calculationmethod. With the radiositymethod, light rays are emittedrom the light source andrelected when they strike asurace.

Ray tracingLight simulation calculationmethod. The ray tracing methodis based on rays o light that areemitted rom an imaginary eye tothe model and the light sources.

Recessed foor luminaireA luminaire which is ush-mountedin the oor or ground and has ahigh → protection mode. Theseluminaires are used to mark outroutes and pathways and also todramatically illuminate objectsand architectural details.Recessed luminaires→ Downlight

RefectionThe ability o suraces to reectlight. The percentage reection isknown as the reectance, defnedas the ratio o reected to inci-dent → luminous ux. Reectioncan be directed or diuse.

RefectorLight-directing system basedon reecting suraces. The main

characteristics o a reector areits reectance and spread. Forconcave and convex mirror reec-tors, a urther characteristic isthe curvature o its cross section,

i.e. the reector contour. Parabolicreectors align the light rom alight source located at the ocalpoint into a parallel beam, spheri-cal reectors reect it back to theocal point and elliptical reectorsocus it to a second ocal point.

Refector lampLuminaires with integral → reec-tor. The reector lamps are avail-able with dierent beam angles.A special orm is the → coolbeamreector.

ReractionPhenomenon through which thedirection o light is changed asit passes through mediums o diering densities. The reractivepower is given by the reractiveindex.

Re-ignitionThe restarting ater switching o or ater a power ailure. Many→ discharge lamps can only bere-ignited ater a cooling downperiod. In these cases, instantre-ignition is only possible withthe aid o special high-voltage→ igniters.

RelaysA switch which is actuated bycurrent. A relay is usually acti-vated via a separated circuit andcan open or close one or morecircuits.

Restaurant lightingCharacteristic: low → ambientlighting, ocal light on the tablewith accentuation o specifcareas o the room and decor. Use

o →

lighting controls to adjustthe lighting to suit the dierentrequirements during daytime andnightime.

RGBAbbreviation or Red Green Blue.The RGB colour mixing used inlighting technology is based onadditive colour synthesis to pro-duce light o dierent colours.

Rod vision→ Scotopic vision

Room surace maintenanceactorCalculation value or the mainte-nance plan o a lighting system

which considers the drop in lumi-nous ux due to dirty walls.

SScallopHyperbolic shape due to theintersection o the → light beamand the wall; produced, orexample, by downlights.

ScenographyThe term or scenic eects. Inlighting, scenography reers tothe transormation o a room orarea using light with the inclusiono the dimension o time.

Scotopic visionAlso: night vision. Vision involvingadaptation to → luminances o below 0.01cd/m2. Scotopic visionoccurs through the rod cellswhich are mainly in the periph-ery o the retina. The → visualacuity is low and colours cannotbe perceived, but there is highsensitivity to the movement o observed objects.

Sculpture lens→ Lens with a parallel ribbedtexture that spreads the → lightbeam in one axis, leaving it largelyunchanged in the other axis. Inmuseum lighting, the sculpturelens is used to uniormly illumi-nate tall or long sculptures withan oval beam.

SensorDevice or measuring environ-mental conditions and eventswithin the surroundings. Thesensor measures the value andsends a signal when the limit hasbeen exceeded in order to triggeran action such as adjusting thelighting.

Shop window lightingIn essence, shop window light-ing design is closely linked to→ showroom lighting; it prima-rily involves the use o → accentlighting, oten with theatricalscenic eects using colouredlight, lighting projections anddynamic → lighting control.

Showroom lightingThis describes lighting which isdesigned based on the compo-

nents o horizontal and vertical→ ambient lighting togetherwith → accent lighting; multi-component lighting typicallywith → discharge lamps (ambient

E GuideGlossary



lighting) and → tungsten halogenlamps (accent lighting). Suchretail lighting can oten be usedto convey a company’s corporateidentity.

Solar architectureArchitecture designed to allowsolar energy and → daylight tobe utilised as energy and light,respectively.

Solar protectionTechnical measures which use→ absorption, → reection andreraction to control direct sun-light in order to improve the→ visual comort (glare protec-tion) and reduce the thermal loadin the room.

Solar simulator→ Daylight simulator

SpectrumDistribution o radiation intensityo a light source over a specifcrange o wavelengths. Both→ colour o light and → colourrendition are a result o the spec-trum. The basic types o spectrumare distinguished depending onhow the light is produced: thecontinuous spectrum (daylightand → thermal radiators), thelinear spectrum (low-pressuredischarge) and band spectrum(high-pressure discharge).

Spherolit refectorLight-directing system based onreective suraces with spheri-cal segments. The light intensitydistribution is determined by thereectance, the reector contour,the number o spherical segments

Starter→ Ignitor or → uorescent lamps.

Stroboscopic eect

This is a ickering eect whichresults in the apparent changein the speed o moving objects.This can even go so ar as tomake objects appear to be sta-tionary or move in the oppositedirection. It is caused by lightpulsating at or close to mains re-quency. Stroboscopic eects canoccur when lighting is providedby → discharge lamps. It can beremedied by phase-shited opera-tion (lead-lag circuit, connectingto a three-phase power network)or by high-requency electronic→ control gear.

Sunlight→ Daylight

TTask lightsThese luminaires are predomi-nantly equipped with energy-saving, compact → uorescentlamps or → tungsten halogenlamps and have reely adjustablelight heads and good glare con-trol; they are suitable or use ina wide variety o workplaces.

Thermal radiatorA radiation source rom whichlight is emitted by heating amaterial, generally tungsten,as the ilament material in an→ incandescent lamp.

Thermoluminescence

Trailing edge technologyMethod o dimming in which thepower consumption o the lampsis limited by the trailing edgeo the alternating current wave.

With trailing edge technology, thecurrent is switched on immedi-ately ater the alternating voltagepasses through the zero pointand is switched o beore thenext zero crossing. Trailing edgetechnology is used or controllingelectronic control gear.

TransadapterA device used to connect a lumi-naire, especially a → spotlight or→ oodlight, both mechanicallyand electrically to a → track;used together with an integratedelectronic → transormer or an

electronic → control gear.

TransormerRequired to operate → low-volt-age halogen lamps; a distinctionis drawn between conventionaland electronic transormers.

TransmissionThe ability o materials to trans-mit light. The dimension o trans-mission is transmittance, defnedas ratio o transmitted → lumi-nous ux to incident luminousux. Transmission can be directedor diuse.

Tungsten halogen lampCompact → incandescent lampflled with halogen to preventthe deposit o vaporised flamentmaterial onto the inner glass wall.Tungsten halogen lamps have ahigher → luminous efcacy andlonger unctional lie than gen-eral service lamps

causing colours to ade and mate-rials to become brittle. Ultraviolet→ flters absorb this radiation.

UplightPendant luminaires, wall lumi-naires, oor luminaires or ree-standing luminaires that emittheir light upwards.

Utilisation actorThis actor describes the inu-ence o spatial geometry andthe reectance o its peripheralsuraces on the residual → lumi-nous ux arriving on the defnedworking plane.

Utilisation actor method

Method or calculating theaverage → illuminance in aroom using the → light outputratio, the → utilisation actorand the → luminous ux o thelamp.

V VarychromeAttribute describing luminairesthat can generate light o anycolour, or example, using RGB→ colour mixing.

VDU lightingLighting in administrative build-ings which is heavily regulatedby guidelines and regulations. Itis characterised by requirementsor the illuminance level, lightdistribution and glare limita-tion, specifcally or preventingreections on monitor screens,worktops and keyboards

E GuideGlossary

ERCO guide.pdf

Documents

Transcript of ERCO guide.pdf