A Wavefront Inversion Algorithm Based on Phase Difference Method for Diffractive Optical Imaging System

Abstract

The invention discloses a wavefront inversion algorithm of a diffractive optical imaging system based on a phase difference method. The algorithm includes the following steps: Step 1: Establishing a diffractive optical imaging characteristic characterization including diffraction efficiency and space shift characteristics of the diffractive optical imaging system Model; Step 2: Establish a phase difference wavefront inversion model for the diffractive optical imaging system based on the maximum likelihood method; Step 3: Deduce the defocus diffraction phase expression and defocus diffraction efficiency characterization model based on the scalar diffraction theory; Step 4: Aiming at the spatial shift characteristics of diffraction imaging, based on the block idea of ​​equal halo area, the spatially variable degraded image of the focal plane and the spatially variable degraded image of the defocused plane are processed in blocks; Step 5: Use the particle swarm algorithm based on simulated annealing to analyze the phase difference The inversion model performs a global optimization solution, and outputs wavefront information corresponding to different fields of view. The invention can provide support for the space application of the ultra-large aperture film diffraction optical imaging system in the future.

Description

technical field [0001] The invention belongs to the field of optical remote sensing imaging, and relates to a wavefront inversion algorithm for a diffractive optical imaging system, in particular to a wavefront inversion algorithm for a diffractive optical imaging system based on a phase difference method. Background technique [0002] The thin-film diffractive optical imaging system has the characteristics of super large aperture, short processing cycle, low cost, and light weight, and has become an important development direction for space payloads of high-orbit satellites in the future. However, limited by the diffraction imaging mechanism, compared with the traditional catadioptric system, the thin-film diffractive optical imaging system has various aberrations and large wavefront distortion, resulting in serious image quality degradation. High-precision inversion of wavefront distortion has scientific research significance and engineering application value for applicati...

AI Technical Summary

Problems solved by technology

[0005] Aiming at the problems that the existing wavefront inversion method cannot be fully applied to the diffractive optical imaging system and is limited by hardware, the present invention provides a wavefront inversion algorithm based on the phase difference method for the diffractive optical imaging system

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