Comparison of two stitching algorithms for annular subaperture Hartmann Shack testing method

Abstract

Annular subaperture stitching method is an effective method for testing aspheric surface. Two stitching algorithms for annular subaperture stitching method based on Hartmann Shack sensor are presented. The precision of the stitching algorithms is a major concern. The precision of the two algorithms are analyzed and compared in pertinent cases especially for the tested aspheric surface with different asphericity. The analysis shows that the phase stitching algorithm (PSA) can be used to reconstruct the whole-aperture wavefront for mild aspheric surface and the gradient stitching algorithm (GSA) can reconstruct the whole-aperture wavefront with high precision even for the steep aspheric surface with high noise level of gradient data.