光学学报, 2010, 30 (7): 2022, 网络出版: 2010-07-13
子孔径拼接干涉检测凸非球面的研究
Testing Convex Aspheres by Subaperture Stitching Interferometry
测量 子孔径拼接干涉(SSI) 凸非球面 零位补偿测试 measurement subaperture stitching interferometry (SSI) convex asphere null compensation testing
摘要
在总结各种检测凸非球面方法优缺点的基础上,提出了利用子孔径拼接干涉检测凸非球面的新方法。利用标准球面波前作为参考波面,用干涉法逐次测量非球面各区域的相位分布,去除参考波面偏差以及调整误差后,通过子孔径拼接算法就可以重构凸非球面全口径的面形分布。研究和分析了该方法的基本原理和基础理论,开发了综合优化和误差均化的子孔径拼接算法。设计和研制了子孔径拼接干涉检测装置,并结合实例对口径为140 mm的碳化硅凸非球面进行了子孔径拼接测量,得到了精确的全口径面形分布,其面形分布的峰值(PV)和均方根(RMS)值偏差分别为0.274λ和0.024λ(λ=632.8 nm),且对该非球面进行零位补偿测量,其全口径面形与拼接全口径面形是一致的,面形分布的PV和RMS值的偏差仅为0.064λ和0.002λ,从而提供了又一种定量测试凸非球面的手段。
Abstract
On the basis of summing up conventional testing methods for convex aspheric surfaces,a novel method for testing convex aspheres by subaperture stitching interferometry (SSI) is proposed. A sphere mirror is used as the reference surface,and the phase distribution of each subaperture can be measured by the digital wavefront interferometer. The full surface map is obtained by stitching five subapertures which have been subtracted the theory wavefront error from phase datum and eliminated the translation errors. The basic principle and theory of SSI are researched,and the stitching software and prototype for testing of convex aspheres are devised and developed. A convex SiC asphere with the aperture of 140 mm is tested by this method. As results,the PV and RMS of the surface error after stitching are 0.274λ and 0.024λ (λ=632.8 nm),respectively. For the validation,the asphere is also tested by null compensation,the synthesized surface map is consistent to the entire surface map from the null test,and the difference of PV and RMS error between them is 0.064λ and 0.002λ,respectively. So it provides another quantitive measurement for testing convex aspheric surfaces.
王孝坤, 郑立功, 张学军. 子孔径拼接干涉检测凸非球面的研究[J]. 光学学报, 2010, 30(7): 2022. Wang Xiaokun, Zheng Ligong, Zhang Xuejun. Testing Convex Aspheres by Subaperture Stitching Interferometry[J]. Acta Optica Sinica, 2010, 30(7): 2022.