Digital hologram-based high-precision spherical surface sub-aperture splicing fusion method

Abstract

The invention discloses a digital hologram-based high-precision spherical surface sub-aperture splicing fusion method. The method of the invention is based on digital holographic technology and sub-aperture splicing technology; a spherical surface sub-aperture hologram measured through adopting the digital holographic technology is subjected to digital reproduction, so that sub-aperture phase diagrams can be obtained, and the sub-aperture phase diagrams are subjected to splicing fusion, and therefore a full-field-of-view spherical surface phase diagram can be obtained; and digital reproduction calculation is performed on the obtained sub-aperture hologram data based on an off-axis holographic optical path. The method specifically includes the following steps that: image apodization, frequency-domain filtering, aberration compensation and digital focusing reproduction are performed sequentially; and the splicing fusion of the sub-aperture phase diagrams is completed through adopting a sub-aperture splicing algorithm, and sub-aperture relative position errors are further corrected through iterative calculation, so that the phase diagram of a complete spherical surface can be obtained. The digital hologram-based high-precision spherical surface sub-aperture splicing fusion method of the invention has the advantages of fully-digitized data processing process, high precision, simple operation, high reliability and the like, and can detect data processing of a spherical surface based on the digital holographic technology.

Description

technical field [0001] The invention relates to a digital hologram-based splicing and fusion method of spherical sub-apertures, which can be used for splicing and fusion when digital holographic technology detects the three-dimensional shape of a spherical surface. Background technique [0002] In the three-dimensional shape measurement of the surface of spherical objects, optical interferometry, as a typical non-contact measurement method, has been widely used, especially the standard optical interferometer. By using a standard mirror that matches the parameters of the measured object, the measurement of the surface topography of the measured object can be completed. However, in the surface topography measurement of three-dimensional objects, especially for three-dimensional objects with characteristics such as large aperture, high numerical aperture, and large curvature, due to the limitation of the output beam aperture of the standard interferometer and the specification ...

AI Technical Summary

Problems solved by technology

[0004] In order to solve the problem that the measurement results contain errors due to the inaccuracy of positioning in spherical surface splicing measurement, the present invention proposes a high-precision spherical surface sub-aperture splicing and fusion method based on digital holograms, based on digital holographic technology, using the whole process of data processing With the advantage of digitalization, aberration correction and position deviation compensation are performed, and then the sub-aperture splicing and fusion are completed to obtain the full-aperture phase map of the measured spherical surface

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