为了满足大口径反射镜研磨阶段的面形检测需求，分析了激光跟踪仪测角误差的来源，提出了一种基于S多项式拟合的矫正测角误差的方法，该矫正方法能有效克服采样位置误差和随机误差带来的影响。针对不同频段测角误差，提出母线和米字格采样法，其中母线采样法对10%以内的标定实验随机误差有较好的抑制作用。矫正方法的可行性得以验证，从而为进一步实验提供了理论基础。

In order to meet the surface shape detection requirements during the grinding stage of large aspheric mirror, the sources of angle error are analyzed, and one method for correcting angle measurement errors based on the S polynomial fitting is proposed. This method can effectively overcome the impact caused by the sampling location and random errors. As for the angle errors at different frequency bands, the generatrix and composite sampling methods are proposed, and the generatrix sampling method can suppress the random error within 10% in the calibration experiment. The above correction method is proved to be possible, which provides a theoretical basis for its application in the future experiments.