Design of mixing color optical system based on a novel composite lens array

The development of optics of mixed white light illumination is a challenging problem to provide high uniformity and high-power color mixing and meet many other specific requirements. This study proposes an optical design method of high-power color mixing illumination based on free-form composite lens arrays. The designed composite lens array has a high convergence capability to converge light from different locations to a single point, eliminating the sensitivity to the position of the light source. The system utilizes a freeform mixer to reduce the normalized standard deviation of the chromatic aberration values and the correlated color temperatures. In the design example, the system produces white light with a color different value of 0.008 and a normalized standard deviation (NSD) value of 0.000624 at the lens distance of 25 mm and the focal length of 180 mm. The proposed optical system design method can effectively eliminate the problems of white point shift and color difference in hybrid white light illumination.