旋转支撑法去除元件面形测量的夹持误差

Rotating Chuck Test for Removing Chuck Error of Optical Surface

为实现对光学元件的高精度面形测量,建立了一种旋转支撑结构的高精度测量方法。对该方法的理论原理、数值仿真和误差分析等进行了研究。首先根据元件夹持工况仿真分析了支撑变形的特性。接着用泽尼克多项式拟合波面,建立了旋转支撑法的理论模型,并推导出光学元件去除支撑影响后的面形公式。用仿真分析的方式验证了理论模型,对计算的面形结果与理论面形进行了比较分析。最后,分析了影响旋转支撑法测量精度的误差项。仿真分析结果表明,通过两次旋转支撑结构的方式,可以有效地去除元件支撑造成的面形误差,计算值与真实值之间的误差为支撑误差的泽尼克多项式的高阶对称项,满足元件面形的高精度检测要求。

In order to realize high accuracy test for optical surface, a rotation chuck method is built and its principle, model analysis and error analysis are researched. Based on the optical component mounting case, the property of surface deformation is analyzed. The surface profile is fitted with Zernike polynomials. The principle model of rotation chuck method is studied, and the equation of surface real profile is derived from the model. Then, the principle model is analyzed with numerical simulation method. The results of surface profile and the real surface profile are compared. Finally, the error sources of rotation chuck method are researched. Analysis results indicate that the rotation chuck method can remove mounting error efficiently, the difference between the computed profile and the real profile is the high-order symmetrical Zernike polynomials, which can satisfy the high accuracy requirement of optical surface tests.