Uniform Illumination Design by Configuration of LED Array and Diffuse Reflection Surface for Color Vision Application

Abstract

Illumination uniformity and color mixing results are essential for color vision applications. In this paper, an indirect method is proposed for the uniform illumination, and a mathematically simulated algorithm is developed. We integrate the method of light-emitting diode (LED) array and diffuse reflection surface for uniform illumination system. By considering each single LED as an imperfect Lambertian emitter, we discuss the irradiance distribution over a sphere's inner surface to the three-ring LED array. The sphere's inner surface is a diffuse reflection surface with high hemisphere reflectance. Using the bi-directional reflectance distribution functions (BRDF) of the sphere's inner surface, we simulate the uniformity of the LED illumination at varying distances. Finally, we design a practical LED illumination. The uniformity of practical LED illumination agrees with the simulated result. The results demonstrate the usefulness of this method for uniform illumination design.