4 March 2013 LED color mixing with diffractive structures
Author Affiliations +
Abstract
Lighting solutions with colored LEDs provide many opportunities for illumination. One of these opportunities is to create a color tunable light source. In this way different kinds of white light (color temperature) as well as discrete colors may be realized. This opens the field for applications as mood lighting. But there is always a spatial separation of the distinct LEDs that might get converted into an angular separation by any collimating optics. This angular separation causes such problems like color fringes and colored shadows that cannot be accepted in most applications. Conventional methods to solve these problems include e.g. mixing rods or dichroic filters. A new approach is the use of the dispersive effect of a diffractive structure to compensate the angular separation of the different colors. In this contribution the potential and limitations of diffractive structures in LED color mixing applications are discussed. Ray tracing simulations were performed to analyze such important parameters like efficiency, color performance and the cross section of the color mixing optics. New means for the estimation of color mixing performance were developed. A software tool makes it possible to detect the color distribution within ray trace data and it provides a quality factor to estimate the color mixing performance. It can be shown that the spectral band width has a large influence on the mixing process. Ray tracing simulations are compared with results of an experimental setup such that both measured as well as simulated data is presented.
© (2013) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Theresa Bonenberger, Theresa Bonenberger, Jörg Baumgart, Jörg Baumgart, Simon Wendel, Simon Wendel, Cornelius Neumann, Cornelius Neumann, } "LED color mixing with diffractive structures", Proc. SPIE 8641, Light-Emitting Diodes: Materials, Devices, and Applications for Solid State Lighting XVII, 864107 (4 March 2013); doi: 10.1117/12.2003964; https://doi.org/10.1117/12.2003964
PROCEEDINGS
12 PAGES


SHARE
RELATED CONTENT


Back to Top