非球面拼接测量中的配准误差校正

Calibration of registration error in the sub-aperture stitching testing for aspheric surface

为了抑制配准误差对子孔径拼接测量非球面的影响,采用基于仿射变换和子孔径位置优化的拼接算法,校正由于配准误差引起的子孔径拼接重叠区对应点的不一致性,以提高拼接测量的精度.首先,分析了子孔径重叠区域相位误差不一致性的原因,然后,根据重叠区相位误差最小原则,利用反向求解法,求得配准方程中的各项系数,进行子孔径数据的配准和位置的优化校正.实验结果表明:经过配准误差的校正后,采用同步拼接方法得到的子孔径拼接测量结果与全口径直接测量结果更为吻合.

In order to restrain the influence of matching error in testing of asphere using sub-aperture stitching method, a stitching algorithm is presented that based on affine transformation and position op- timization of sub-aperture, inconsistency of corresponding points in stitching overlap of sub-aperture that caused by registration error are corrected, and improving the accuracy of stitching testing. First, the reason of phase error inconsistency for sub-aperture overlap is analyzed, and according to the princi- ple of overlap phase error minimization, using reverse solution method, coefficients in equation are got- ten. The date registration and position optimal correction for sub-aperture is on doing. Experimental re- sult show that after correcting registration error, the stitching testing result of sub-aperture utilizing method of synchronous stitching are more identical with the direct testing result of whole aperture.