Retroreflection

2-3

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F

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1Angle of incidence 1= Angle of reflection 2

Fragmented parabola

Mircro prism structured mirrors

RetroFlex-louvers are assembled like Venetiam blinds. They are installed either on the interior or within a closed double-skin facade.The aluminium louvers act as efficient retro-reflectors by their micro structured mirror surface. The microstructure is embossed into the aluminium utilizing the mathematics of a Fresnel mirror (R=86%). The smooth surface of the lower side is either white or alu-reflective. In the upper area of a window, the blinds can be installed inversley to improve the natural daylighting of the interior.The diminution factor Fc depends on the position of the blinds and the coating of the glazing.Fc ~ 0,4 - 0,11 SHGC = 0,1-0,2

Litex and Sopharma Building, Sofia, Bulgaria; Arch. Dimitar Pascalev, Bulgaria (2010/2011)Daylight Design: Köster Lichtplanung, Frankfurt, Germany; Gold-certified

“Power Tower” of the Energie AG, Linz, Austria (2008)Arch. Hofer, Zürich, Switzerland and Prof. Kaufman, Linz, AustriaDaylighting: Dr. Helmut Köster, Frankfurt Germany

State of the art:Mirror blinds are closed,no view to outside,no daylighting

Innovation ofRetroFlex louvers:

blinds are open,good visual transmission,

enhanced daylighting

Microstructure with Fresnel-Optic

View out

Focus

View out +daylight

Retro-cooling

fragment. Parabola

Sun

Parabola

RETROFlex®

RETROSolarGesellschaft für Tageslichtsysteme mbH

Danziger Str. 51 · D-55606 KirnT +49 (0)672 912079F +49 (0)672 912080

info@retrosolar.de · www.retrosolar.de

Landesdenkmalamt Ba-Wü., Esselingen, Germany; Arch.: Odilo Reuter, Esselingen, GermanyDaylight- and facade planning: Köster Lichtplanung, Frankfurt, Germany

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Light redirection of RetroLux louvers.

Sun

Development goals:- improved visual transmissionsimultaniously:- protection from overheating- very good SHGC-value through reflective partsimultaniously:- improved daylighting through lightshelf 2

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Optical functions of the RetroLux louvers: • Redirection of the overheating sun back into the sky and • glare-free illumination in the depth of the room

RETROSolarGesellschaft für Tageslichtsysteme mbH

Danziger Str. 51 · D-55606 KirnT +49 (0)672 912079F +49 (0)672 912080

info@retrosolar.de · www.retrosolar.de

Lightshelf

RETROLux®

RETRO-Reflektor

Slim blind

Visual transmission (76 %)

Very good illumination in the depth of the room

Visual transmission

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