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

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 optimization 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 principle of overlap phase error minimization, using reverse solution method, coefficients in equation are gotten. The date registration and position optimal correction for sub-aperture is on doing. Experimental result show that after correcting registration error, the stitching testing result of sub-aperture utilizing method of sequence stitching and synchronous stitching are more identical with the direct testing result of whole aperture.