一种任意图形编码的（0，π）型二维位相光栅的设计

Design of an Arbitrary-geometry(0,π)Model Binary Phase Grating

基于分析和比较各种编码图形的二维二值位相光栅的优缺点．提出了一种设计任意图形编码的二值位相光栅的方法。该方法主要分为两步．首先以获得最高衍射效率为基准．寻求任意图形编码的二维二值位相光栅的初始结构．然后采用一种迭代算法优化初始结构获得期望的光强分布。设计了７个可等强分束的二维二值位相光栅，其衍射效率均大于８０％，均匀性偏差均小于０．０１％。

A method to design an arbitrary-geometty(0,π)model binary phase grating isproposed after we have analyzed and compared the characteristics of all kinds of codingschemes.The development of this method can be divided into two steps:firstly,to get thehighest diffraction efficiency,we find the initial binary phase structure,secondly,we adoptan iterative method to optimize above initial structure to get expected intensity dispersion.We have designed 7 binary phase gratings to split the incident light beam into equal-intensitybeams. Their diffraction efficiencies are all above 80% and their uniformity deviations areall below 0. 01 %,which are better than other reported'results to the best of our 1<knowledge.