Precise design of the focused spot and its performance analysis

In this paper, the precise design of the diffractive optical element (DOE) is completed to control the shape of t he focused spot. By using the hybrid algorithm, merging Hill-climbing with Simulated Annealing, and adjusting the weight factor in the optimization, the DOE can realize high uniformity at the main lobe (non-uniformity is less than 10%) and no "blocking" effect around the hole (the ratio between the peak intensity around the hole and the average value of the main lobe is less than 0.01%) simultaneously. Different sampling intervals are used to examine the performance of the DOE, and the simulated results show that the calculated performance parameters are true and accurate with the precise design, and the fence effect induced by discretization with the traditional sampling inter