A Polynomial Description Based Multi-Objective Optimization Method for Freeform Beam Shaping System

The optimization of freeform for beam shaping system is mainly concerned with improving optical metrics like beam pattern and uniformity, while quality evaluation of freeform surfaces has recently received more attention. A polynomial description based multi-objective optimization method is proposed to simultaneously improve beam shaping performance and control the steepness of freeform. In the given example, multiple freeform polynomials obtained through optimization achieve an average improvement of 10% in uniformity and a 95.06% reduction in the Standard Deviation (SD) of the rate of change of Gaussian curvature compared to the initial polynomial. Moreover, the solution set obtained from optimization gives decision makers the ability to adjust the quality of freeform surfaces according to practical needs.