Numerical simulation of light propagation through a diffuser

Diffusers are important elements of many illumination systems, for example, in computer and mobile phone displays or advertising panels, etc. In this article, the light propagation in a diffuser with optically soft inclusions is described with the help of the Fokker–Planck equation, i.e., a transfer equation with a diffusion term in the space of radiation propagation directions. The coefficient of angle diffusion is calculated using the Mie theory. The equation is solved numerically using the stochastic analog method, and the space and angle distribution of the radiation that passed through the diffuser is calculated. The results can be useful for diffuser parameters optimization, and the method can be applied to many problems of turbid media with optically soft particles.