针对前人的数学模型，对瑞奇角、旋转角和系统波像差这几个主要精度影响因素进行了仿真分析。结果表明：当瑞奇角的测量误差控制在0．5°以内时，对测量结果影响很小；由于平面镜的面形误差是连续和旋转对称的，所以旋转角测量误差对测量结果影响很小；当系统波像差系数的测量误差|△W_n，m|≥0．05λ时会影响拟合精度。此仿真结果为提高大口径平面镜检测精度提供了理论依据。

In view of the mathematics model,Simulation and analysis for several main influencing factors such as measurement errors of Ritchey angle,rotation angle and wave-front aberrations is carried out. Results show that the Ritchey angle measurement error to be less than 0.5° is insensitive to the testing accuracy. If the figure errors of flat are consecutive and revolving symmetrical,influence is small to testing result. Wave-front aberrations in the event of |△W_n,m|≥0.05λ influence on fitting accuracy. The simulation result provides theory basis for improving the measurement precision of large flat.