不同衍射计算方法比较及误差分析  

Comparison of different diffraction calculation methods and error analysis

作　　者：刘江涛 李洪儒[1] 邓国亮[1] 周寿桓[1] LIU Jiangtao;LI Hongru;DENG Guoliang;ZHOU Shouhuan(Sichuan University,College of Electronics and Information Engineering,Chengdu 610000,China)

机构地区：[1]四川大学电子信息学院,成都610000

出　　处：《激光杂志》2021年第12期18-29,共12页Laser Journal

基　　金：四川大学博士后交叉学科创新启动基金项目(No.BHJC201911);四川省科技计划资助项目(No.2021YFG0323)。

摘　　要：对多种衍射计算方法进行了比较及误差分析,为衍射计算方法的合理选择提供了指导。研究表明衍射距离小于波长的情况下,经典标量衍射或矢量衍射都有较大误差,需要使用电磁场仿真软件进行计算;波长量级下矢量衍射模型较为准确;一般距离下,矢量衍射与标量衍射计算结果几乎一致。标量衍射模型中积分法和角谱法计算结果的差距随着衍射距离的增加逐渐增大。相同物理尺寸下积分法的结果更加准确。增加网格采样点数只能够提高积分法的精度,对于角谱法可以通过增加衍射平面的物理尺寸来降低计算误差。通过物理实验验证了计算结果的正确性。The comparison and error analysis of various diffraction calculation methods are carried out to provide guidance for the reasonable selection of diffraction calculation methods.It is shown that the classical scalar diffraction or vector diffraction has a large error when the diffraction distance is smaller than the wavelength,and it is necessary to use the electromagnetic field simulation software for calculation;the vector diffraction model is more accurate at the wavelength scale;the calculation results of vector diffraction and scalar diffraction are almost the same at the general distance.The difference between the calculation results of the integral method and the angular spectrum method in the scalar diffraction model increases gradually with the increase of the diffraction distance.The results of the integral method are more accurate for the same physical size.Increasing the number of grid sampling points can only improve the accuracy of the integration method,and the calculation error can be reduced by increasing the physical size of the diffraction plane for the angular spectrum method.The correctness of the calculation results is verified by physical experiments.

关 键 词：衍射计算 标量衍射 矢量衍射 角谱传输 

分 类 号：O431.1[机械工程—光学工程]