Modulation-based centering method and system

Abstract

The invention discloses a modulation-based centering method and system, and the method comprises the steps: fixing a detector on a multi-degree-of-freedom displacement platform, and enabling a point light source to form an image on an image plane of the detector; displacement modulation in the x direction and the y direction is applied to the multi-degree-of-freedom displacement platform, so that the multi-degree-of-freedom displacement platform moves in the x direction and the y direction; wherein the detector moves along with the movement of the multi-degree-of-freedom displacement platform; acquiring a plurality of frames of images in the motion process of the multi-degree-of-freedom displacement platform; according to the obtained multiple frames of frame images, the average neutral position of multiple light spots is obtained through calculation; performing circumference fitting on the calculated average neutral position of the plurality of light spots to obtain a circumference fitting result; and according to a circumference fitting result, obtaining a circle center position, namely a static center position of a light spot on an image plane in a non-modulation state of the detector. According to the method, random errors and system errors are reduced, and the centering precision is improved.

Description

Technical field [0001] The present invention belongs to the field of image processing technology, in particular to a modulation-based centering method and system. Background [0002] Scientific-grade optical image detectors such as CCD or CMOS APS, as mainstream optical images converted into electronic signals, are widely used in astronomy, biology, ultraviolet imaging, power line detection, night vision imaging, low-light safety and other scientific research. In the current space missions, satellites, intercontinental strategic missiles, spacecraft and other aerospace vehicles in order to determine and control their own attitude, as well as the optical axis of specific missions to point or target, the vast majority of the use of star sensors and other optical image detector attitude sensors. [0003] Centering refers to the high-precision positioning of the center of the spot under the agreed center definition conditions, which is the basic problem of astrometry, microscopic ima...

AI Technical Summary

Problems solved by technology

Existing technologies mainly include centroid method, threshold centroid method, and parameter estimation. These methods are based on the research of centering methods of static light spots, and the random error and systematic error restrict the centering accuracy.

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