数字波面干涉仪测试光学材料均匀性

Homogeneity Measurement of Optical Materials by a Digital Wavefront Interferometer

本文叙述了一种不受干涉仪系统误差及试样加工误差限制的测试光学材料均匀性的方法。借助于电子计算机,通过对四张干涉图的分析与处理,可以精确计算不包括线性变化的折射率偏差及厚度偏差。给出了两块玻璃的测试结果,并进行了测量精度的分析,对25mm厚的玻璃,精度为4×10^(-7)。

This paper describes a method for the homogeneity measurement of optical material which is free from the system errors and the sample geometrical errors. Using a microcomputer the variations of the refractive index and the thickness apart from a linear slop can be measured accurately by means of analyzing and processing four interferograms. Measurement results of two pieces of glass are given with the accuracy analysis.It shows the accuracy is 0.0000004 for a 2.5 cm thick sample.