针对几何映射理论不考虑衍射效应,无法得到精确的输出光束,且输出光束存在严重振铃效应的问题,提出一种设计衍射光学元件的新算法。设置一个用于反映衍射效应的参量,通过迭代的方法确定该参量的最佳取值,再用改进的Gerchberg-Saxton(GS)算法对初始相位进行修正,最终得到所需衍射光学元件的相位分布。该算法与传统GS算法相比,能有效抑制散斑和振铃效应,得到均匀性更好的输出光束。

This study proposes a new algorithm for designing diffractive optical elements to solve the issues resulting from the fact that geometric mapping theory does not involve the diffraction effect, which results in an inability to obtain a precise output beam and a serious ringing effect of the output beam. The proposed algorithm sets a parameter for reflecting the diffraction effect. The optimal value of this parameter is determined using an iterative method. The initial phase is modified using the the improved Gerchberg-Saxton (GS) algorithm, and the required phase distribution of the diffractive optical elements is finally obtained. When compared with the traditional GS algorithm, the proposed algorithm can effectively suppress the speckle and ringing effect and obtain an output beam with improved uniformity.