为了评价平面镜面形误差, 采用基于条纹反射法的面形检测原理、通过平面镜法线偏移实现面形误差评价的方法。将正弦条纹投射至光屏, 经被测平面镜反射至相机, 通过小孔成像原理和四步相移法获得被测平面镜上一点的法线, 并与经最小二乘算法面形重建的该点理论法线比较, 获得该点法线偏移, 利用法线偏移实现对平面镜的面形评价。对测量方法进行计算机仿真, 以证明其正确性, 搭建实验测量系统, 并对某一款手机屏幕进行测量实验。结果表明, 该测量方法的重复性精度优于1mrad, 测量重复性高。该研究为玻璃面板等具有高反射特性的平面面形误差提供了参考。

In order to evaluate the plane mirror surface shape error, the surface shape detection principle based on the fringe reflection method was adopted, and the method for realizing the plane shape error evaluation by the plane mirror normal offset was used. The sine fringe was projected on the light screen, reflected by the plane mirror to the camera, and the normal of a point on the plane mirror was obtained through the imaging principle of the small hole and the four-step phase shift method. And this point was reconstructed by the least square algorithm surface shape. Theoretical normal comparison was used to obtain the normal offset of the point, and the surface shape evaluation of the plane mirror was achieved by using the normal offset. Computer simulation of the measurement method to prove its correctness; set up an experimental measurement system, and perform measurement experiments on a certain mobile phone screen. The results show that the repeatability accuracy of this measurement method is better than 1mrad, and the measurement repeatability is high. This study provides a reference for the flat surface shape error of glass panels and other products with high reflection characteristics.