Maladjustment error correction method for large-aperture and large-field-of-view telescope

Abstract

The invention relates to a maladjustment error correction method for a large-aperture and large-view-field telescope. The method comprises the steps of: (1) collecting under-sampling imaging light spots of on-axis and off-axis view fields by using a far-field detector; (2) performing target extraction and view field matching on the imaging light spots of each view field on the axis and outside theaxis; (3) calculating an image definition function of the under-sampling imaging light spots of each view field in an initial maladjustment state; (4) calculating a new secondary mirror position by using an optimization algorithm, and changing the secondary mirror position through a six-degree-of-freedom driver; (5) acquiring far-field under-sampling imaging light spots of each view field again,performing target extraction and view field matching, and calculating an image definition function of the light spots of each view field; and (6) judging whether the correction result meets a termination condition or not, if yes, ending the correction process, and otherwise, repeating the steps (4)-(6). According to the invention, on the basis of the image definition function of the far-field under-sampling imaging light spots, the online, closed-loop and high-precision correction process of the maladjustment error of the large-aperture and large-view-field telescope can be realized by using an optimization algorithm.

Description

technical field [0001] The invention relates to the field of integrated assembly and adjustment of telescope systems, in particular to a method for correcting misalignment errors of large-aperture and large-field-of-view telescopes based on the sharpness function of far-field undersampling imaging spot images. This method is suitable for the online adjustment of the telescope optical system whose imaging spot is under-sampled. Background technique [0002] In order to detect farther and fainter targets, the aperture and field of view of telescopes are constantly increasing. However, during the working process of the telescope, affected by factors such as gravity, wind load, vibration, and temperature changes, the relative positions of its optical mirrors will change, and misalignment errors will be introduced into the system, making the imaging quality unable to meet the use requirements. At present, the online correction technology of the system misalignment error of the l...

AI Technical Summary

Problems solved by technology

Due to the cumbersome implementation process and complex algorithm, the undersampling image reconstruction technology cannot be directly applied to the online and closed-loop correction process of the telescope misalignment error

At present, the misalignment error correction technology of large aperture and large field of view telescope mainly adopts direct wavefront detection method or image-based wavefront detection method such as phase difference method (Phase Diversity, PD), phase recovery method (Phase Retrieval, PR), etc. , but it is necessary to add a wavefront detection device to the optical system, which increases the complexity of the system, and requires wavefront measurement and reconstruction, resulting in a complicated calculation process

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