This invention relates to the field of optical precision inspection, and particularly to a sub-aperture stitching
inspection method based on a frequency-domain and spatial-domain collaborative strategy. The method includes: acquiring discrete phase data of the sub-apertures; constructing a continuous
physical field model; performing coarse alignment of adjacent sub-apertures using frequency-domain
phase correlation technology to obtain integer pixel displacements between adjacent sub-apertures; performing sub-pixel fine alignment using a numerical
gradient method based on the continuous
physical field model and a normalized cross-
correlation function with an embedded
geometric error culling operator; constructing a global robust
energy functional for
global optimization; solving for the zero-curvature
pose under a floating reference, and then performing
Gaussian gradient weighted fusion and adaptive orthogonal base
surface reconstruction to obtain the full-aperture
surface shape of the large-aperture optical element. This invention solves the problems of strong initial value dependence, displacement-tilt degeneracy, cumulative error warping, and sensitivity to outliers in traditional sub-aperture stitching inspection methods, achieving ultra-high precision and high robustness in the sub-aperture stitching inspection of large-aperture optical elements.