Research Article

Micro-optical structures for daylighting and led systems^★

Green Building Research & Development GmbH, Oberkasseler Str. 6, 40545 Duesseldorf, Germany

^* e-mail: helmut.mueller@greenbuilding-rd.com

Received: 8 February 2017
Received in final form: 2 July 2017
Accepted: 27 July 2017

Abstract

Different micro-optical structures have been developed for the application in transparent building elements like windows or glazed partitions. In cooperation with the Department of Microstructure Technology, TU Dortmund, as well as partners from research institutions and industry solutions for the following two tasks were elaborated: (1) two-sided structures on glass panes for redirection of direct sunlight into the depth of rooms improving daylighting; and (2) one-sided structures on clear panes, edge-lit by LED, for one-way and selective light emission. High demands were made on the small structures (50–200 μm) as to efficiency of light redirection respectively light emission, and quality of image. Technologies for large scale manufacturing are developed in cooperation with partners from industry. Having tested laboratory samples (100 mm × 100 mm) successfully, larger prototypes are produced in hot embossing and UV embossing technique. Optimization of structure geometry and manufacturing process is continuing while design solutions for component and luminaire integration are developed. Architectural applications in transparent building elements for combined natural and artificial lighting are demonstrated, achieving high quality and low energy room illumination.