为实现高精度瑞奇康芒法检测，利用检测系统光瞳面与被测平面镜二者间的坐标转换关系，结合最小二乘法直接对测得的系统波像差进行恢复，通过两角度检测分离由光路调整引入的离焦误差，得到更为精准的平面镜面形。分析光路中测试距离对坐标转换关系以及瑞奇角求解精度的影响，根据仿真分析结果确定实验方案。实验中采用两角度检测，对测试波前进行恢复并分离系统调整误差后，最终得到被检平面镜面形，结果峰谷(PV)值为0.182λ、均方根(RMS)值为0.0101λ，对比干涉仪直接检测结果PV值为0.229λ、RMS值为0.013λ，PV检测精度优于λ/20，RMS检测精度优于λ/100，实验结果证明了此种面形恢复方法的有效性以及测试距离精度分析理论的正确性，从而实现了瑞奇康芒法高精度检测。

In order to realize high precision Ritchey-Common test for large flat mirrors, the relationship between the system pupil coordinate and test flat mirror surface coordinate is utilized to dispose the test wavefront, and then combine with the least square method to detach the alignment errors which are caused by the adjustments of optical system, after this an exact flat surface can be obtained. It analyzes the effects of the test distance on the relationship between the two coordinates and the value of Ritchey angle, and makes the test program according to analysis. In the test process, two measurements in different angles have been taken and the wavefront is found, after detaching the power errors, the peak-valley (PV) and root mean square (RMS) of the final results are 0.182λ and 0.0101λ, compared with the results of Zygo which are 0.229λ and 0.013λ for PV and RMS, the test accuracies of PV and RMS can reach λ/20 and λ/100, respectively. The experimental results prove that this method is effective to calculate the test flat surface and the theory of accuracy analysis is correct, it also realizes the high accuracy of Ritchey-Common test.