By : R. S. Mandal · 2006. 5. 10. · T5 Good T12. 70% T12 80% T8 T5. VISUAL ENVIRONMENT Vp Visual...
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By : R. S. Mandal
Transcript of By : R. S. Mandal · 2006. 5. 10. · T5 Good T12. 70% T12 80% T8 T5. VISUAL ENVIRONMENT Vp Visual...
By : R. S. Mandal
Light Sources
Heat radiation Electrical radiation Luminescenceglow worm
natural
light sources
sun
lightning
Heat radiation Electrical radiation Luminescence
incandescent lamps mercury lamps
(without phosphor)
metal haline lamps
sodium lamps
diodes
blended mercury lamps
fluorescent lamps
mercury lamps (with phosphor)
tungsten halogen lampsartificial
light
sources
Light Sources
Basics of lighting
Luminous flux
Luminous flux is the light output
of a light source.
Unit: 1 lumen (lm)
Light intensity
Light intensity is the measure
of lightoutput in a specified
direction.
Unit: candela (cd)
Light intensity
Basics of lighting
Basics of lighting
Illumination
Average illumination of a
surface is luminous flux
per unit area.
Lux =Lumen
m2
300 Luxroom center
2500 Luxinside window
10 Lux in the cellar
6000 Luxunder marquee
100000 Luxin the Sun
10000 Lux in the shadow
Illumination (Lux)
Basics of lighting
LuminanceLuminance is the measure of the
brightness of a surface
upon the eye.
Unit: 1 candela/m2 (cd/m2 )
Luminance depend on the surface
size seen and the light intensity,
reflected by the surface regards
the eye.illiuminated surface
visible surface
light intensity
T12
65%
T8
72%
T5
85%
6000K Daylight
4000K Cool White
3000K Warm White
2,700K Warm
ModelingModelingModeling
Relative response
of the human eye
to the colours
present in daylight
380
0,5
1,0
0
780
700 (nm)600500400
Sunbed lamps
Photocopying lamps
Black-glass lamps
U.V. I.R.Light
GLS lamps
Halogen lamps
Fluorescent lamps
Low pressure sodium
HID lamps:
- mercury HQL (MBF)
- sodium NAV (SON)
- metal halide HQI
Heating lamps
(cooker lamps)
Natriumdampf-Niederdrucklampen
The effect of colour on visibility
BetterT8
BestT5
GoodT12
70%
T12
80%
T8
T5
VISUAL ENVIRONMENTVISUAL ENVIRONMENTVpVp Visual PerformanceVisual Performance
Visual AmbienceVisual Ambience VaVa VcVc VVisualisual ComfortComfortTyping
VDUTelephoning
Thinking
Reading
Writing
Discussion
QUALITY FEATURES IN LIGHTINGQUALITY FEATURES IN LIGHTING
