非球面零位补偿检测中非线性误差的影响及去除

非球面零位补偿检测中会引入非线性误差,利用光线追迹的方法获得了干涉测量坐标系和非球面镜面坐标系之间的非线性关系。对某有效通光口径为860mm的体育场形离轴非球面反射镜的零位补偿检测,利用光线追迹结果进行坐标反变换的数据处理方法,对上述非球镜面面形数据进行了镜面矢高分布数据的非线性校正;通过分析对比非线性校正前后的数据,对计算机辅助装调过程的影响,证明经过非线性校正后的镜面面形矢高数据可以加速计算机辅助装调过程收敛。

Effect and Removal of Nonlinear Error in Aspheric Mirror Null Testing

Null testing of aspheric mirrors induces nonlinear errors,the nonlinear relation between interferometry coordinate and aspheric mirror coordinate have been obtained by ray tracing. Through analyzing the null testing process of one stadium-shaped off-axis aspheric mirror with an effective clear aperture of 860 mm, the surface shape data of the aspheric mirror provided by the null testing had been corrected by the coordinate inverse transforming method with the ray tracing result. Through the contrast analysis of the effect in computer-aided alignment between corrected and uncorrected surface data, it can be concluded that after nonlinear corrections, the surface shape data of aspheric mirrors can meet the requirement of computer-aided alignment.