大口径凸非球面子孔径拼接干涉检测中的各子孔径之间为离轴形式,各子孔径之间除了平移和倾斜变换外,还含有旋转变换,测量结果中不可避免地会出现参考面未对准的情况,当进行数据拟合处理时,需要把由未对准造成的误差去除。本文在平面检测的最小二乘拟合基础上,对拟合算法进行了改进,从而实现了离轴子孔径的拼接检测拟合。为了验证算法的有效性,采用Matlab对口径为1m的大口径凸非球面的子孔径拼接检测的拟合过程进行了仿真实验,实验结果表明,离轴式大口径凸非球面干涉检测的子孔径拼接可采用改进后的最小二乘法拟合而成,且拟合精度可达到0.0048λ。 Large aperture aspheric sub-aperture splicing interference detection sub-aperture in the form of off-axis between the sub-aperture in addition to translation and tilt transformation, but also contains a rotation transform, the measurement results will inevitably appear the reference surface is not In the case of alignment, the error caused by misalignment needs to be removed when data fitting is performed. In this paper, based on the least square fitting of plane detection, the fitting algorithm is improved, so that the fitting test of off-axis aperture is realized. In order to verify the validity of the algorithm, Matlab simulation of subaperture splicing detection of large diameter convex aspheric surface with a diameter of 1m is carried out. The experimental results show that the subaperture of off-axis large-aperture aspheric interference detection Stitching can be improved by the least squares fit, and the fitting accuracy can reach 0.0048λ.