离轴椭球面的反射式补偿检验

使用要求离轴椭球镜的面形PV(峰谷)值优于0.4λ(λ=351 nm)。根据三级像差理论球差表达式和补偿检验原理,得出检测光路中球面补偿镜的半径表达式。由已知数据求解补偿光路的初始结构参数,并带入软件中得到优化后的设计结果,优化后的结果和初始结构参数没有变化,说明补偿光路的求解方法是正确的。考虑到元件的加工误差和检测光路的调试误差,将误差带入检测光路进行模拟分析后,得出被检元件的面形精度:取98%的合格概率时,椭球镜的面形PV为0.379λ(λ=351 nm),能够满足使用要求,说明离轴椭球面的反射式补偿检验法是可行的。

Mirror-compensation test of abaxial elliptic surface

The usability requires that the surface PV(peak to valley)value of off-axis elliptic surface should be less than 0.4λ(λ=35 1nm).According to spherical-aberration expression of the third-order aberration theory and compensation test principle,the radius expression of spherical compensator was obtained for the test optical path.Based on the known data,the initial configuration parameters of compensation optical path was solved,which was brought into software,giving fine design results.The initial results and the fine design results had no changes,and it shows that compensation optical path solve method is correct.Considering the manufacture errors of elements and the adjustment errors of test optical path,after the simulation analysis,with errors brought into the test optical path,the under-test element surface precision was gotten: when the eligibility probability was 98,the elliptic surface PV was 0.379λ(λ=351 nm).It meets the usability requirement,and it shows that the method of mirror-compensation test of off-axis elliptic surface is feasible.