Hybrid Algorithm for Precise Design of Diffractive Optical Elements for Beam Shaping

Many kinds of optimization algorithm have been applied to design diffractive optical elements (DOEs) for beam shaping. However, only the selected sampling points are controlled by these optimization algorithms, the intensity distribution of other points on the output plane is always far away from the ideal distribution. In our previous research, the non-selected points were well controlled by using a hybrid algorithm merging hill-climbing with simulated annealing, but this hybrid algorithm is time-consuming. In this paper, a new hybrid algorithm merging Gerchberg-Saxton algorithm with gradient method is presented. Because of the use of iterative algorithm, the optimization time is largely reduced. The intensity distribution of the non-selected points as well as that of the selected points is well controlled, and good performance of beam shaping is obtained. Finally the experimental results demonstrate the good performance of this algorithm.