Hybrid simulation of thermo-optical effects in laser-based white light sources

The development of laser-based white light sources is the next step in the evolution of automotive lighting systems. The phosphor used for light conversion is one of the most limiting factors of the overall performance of said sources. To achieve the desired light distributions for automotive applications a small size of the light emitting surface is necessary. While highly focused laser radiation leads to a smaller spot size on the phosphor’s surface it also causes a high thermal load. The conversion of monochromatic laser light to white light is inherently connected to thermal losses. Both effects lead to thermal nonlinearities and mechanical stability issues. In the scope of the joint research program HYbrid Multiscale Numerical Optical Simulation located at Hannover Centre for Optical Technologies HOT granted by "Nieders. Vorab" our group develops a model to describe said thermal behavior. It is used for the identification of parameters for optimization of light conversion and remote phosphor systems. In our paper we present a concept to simulate the interaction of optical and thermal effects by combination of the Finite Element method and classical raytracing methods