基于非理想标准镜的子孔径拼接干涉检测技术研究

在大口径光学镜面的检测中，随着参考镜尺寸的增加，加工精度的制约，重力变形，温度，环境等因素的影响使得参考镜在检测中已经不能作为理想平面镜。文中基于最大似然估计（ML）算法，Zernike 多项式拟合对利用非理想平面镜作为参考镜的子孔径拼接检测建立了一套合理的拼接算法和数学模型。并结合工程实例，完成了对2.5 m3.5 m 椭圆形平面镜的模拟拼接实验，拼接前后全孔径面形误差分布是一致的，其PV 值和RMS 值的偏差分别为0.022 与0.001 3 。全口径相位分布的PV 值与RMS 值的相对误差分别为2.81%与0.81%。实验结果表明:利用ML 拼接算法可以高精度地完成对参考镜为非理想平面的大口径平面镜的拼接检测。

Sub-aperture stitching interferometry based on non-ideal standard mirror

To the testing of large-diame ter optical mirror, with the increase in the size of the reference mirror, it can't be treated as an ideal plane mirror because of the constraints of the machining accuracy, gravity deformation, temperature, environment impact. Based on the maximum likelihood estimation, Zernike polynomials fitting, a reasonable stitching algorithms and mathematical models was established for non-ideal standard lens sub-aperture stitching. Stitching experiment was accomplished on the computer with a 2.5m3.5m oval plane mirror as an engineering example. The full-aperture surface error distribution after stitching was consistent with the original. PV and RMS deviation were 0.022 and 0.001 3 . The full aperture phase distribution of the PV value and the RMS value of relative error was 2.81% and 0.81% respectively. The experimental results show that: large-diameter plane mirror can be tested with non-ideal reference mirror in high precision using the ML algorithm.