Performance analysis of a DTIRC-LED illumination structure

Abstract

The Dielectric Total Internal Reflecting Concentrator (DTIRC) is a type of non-imaging optic that has been used in the past to increase the collection efficiency of photovoltaic (PV) cells and photodetectors. It does this by redirecting energy impinging on its largest aperture to a smaller aperture to which the absorber is attached. This paper explores the use of non-imaging optics for light emission control when combined with a Light Emitting Diode (LED). In this case, the smallest aperture of the concentrator acts as its input and the largest aperture as the output. This allows control of the angular characteristics of the emitted light beam and an increase of the illuminance at the target plane, which is of particular relevance in applications such as illumination and optical wireless communications. Its compact size and design characteristics make the DTIRC a more desirable geometry compared to other non-imaging optics when used as a first or secondary optic to control the emission characteristics of a light source. This paper reports the correlation between simulation and experimental results that validate the ability of DTIRCs to collimate the output beam of extended light sources.