An Equivalent Analysis Method Using the Imaging Law of the Off-Axis Three-mirror Optical System

Abstract

The invention relates to an imaging theory of an optical system, and proposes a theoretical research method for analyzing a relationship between visual axis variations and imaging positions of an off-axis three-mirror optical system. The invention specifically discloses an equivalent analysis method using an imaging rule of the off-axis three-mirror optical system. The equivalent analysis method can realize imaging position compensation of the off-axis three-mirror optical system, and improves the imaging and positioning precision of the off-axis three-mirror optical system. The equivalent analysis method is characterized by comprising the steps of making an off-axis three-mirror system be equivalent to a single reflection system, specifically establishing a single spherical mirror imagingmodel, deducing an imaging formula by utilizing equivalent and coordinate transformation mathematical method theory, converging parallel light beams passing through a sphere center of a spherical mirror into a point Pd on a focal plane CCD under the action of the mirror, wherein the point Pd is an image of a telecentric light source formed on the focal plane, converting imaging coordinates Ps inan ideal coordinate system into coordinates Pr in an actual imaging plane, and deducing a mathematical expression of imaging coordinates Pr of an actual CCD' after a visual axis of the single spherical mirror imaging model changes. The equivalent analysis method is mainly applied to the imaging analysis of the optical system.

Description

technical field [0001] The invention relates to an imaging theory of an optical system, in particular to a theoretical analysis of the visual axis variation and system imaging of an off-axis three-mirror optical system. Specifically, it involves the equivalent analysis method of the imaging law of the off-axis three-mirror optical system. Background technique [0002] The off-axis three-mirror optical system does not produce chromatic aberration, has no secondary spectrum, uses a wide band, can make the aperture large, and is easy to reduce weight. The three-mirror can obtain a larger field of view, and it is easy to control the stray radiation of the optical system. At the same time, because the off-axis system has no central obstruction, the luminous flux entering the optical system is relatively large, which makes the image plane illumination more uniform and high-resolution imaging, which can meet the requirements and development direction of the space camera for the opt...

AI Technical Summary

Problems solved by technology

Due to the large number of mirrors in the off-axis three-mirror system, the absence of the central optical axis of each mirror, and the off-axis and asymmetry of the optical structure, it is very difficult to assemble the system

At present, the method of combining initial positioning and computer-aided adjustment is mainly used. The assembly process will bring position errors of optical components, which will change the imaging axis of the system, generate imaging positioning errors, and reduce the imaging accuracy and quality of the camera.

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