In-orbit on-satellite Infrared radiation calibration system of multi-light integrated large-aperture space camera

Abstract

The invention provides an in-orbit on-satellite Infrared radiation calibration system of a multi-light integrated large-aperture space camera. A low temperature calibration gray body and a high temperature calibration black body are alternately moved into a light path to obtain corresponding images, by obtaining a radiance difference value between the low temperature calibration gray body and thehigh temperature calibration black body and the difference value of picture element gray values of the corresponding images, the influence of internal stray radiation of the camera is effectively removed, and by obtaining the radiation responsivity of the corresponding pixel elements through data processing, the calibration accuracy and the level of quantitative inversion are improved.

Description

technical field [0001] The invention relates to the technical field of space optics, in particular to an infrared radiation calibration system for a large aperture infrared space camera on an orbiting star. Background technique [0002] With the development of space optical remote sensors, the aperture of visible light space cameras has gradually increased to 1m, 1.5m, or even 2.0m and larger. Using the large optical aperture of visible light cameras, infrared spectroscopic design is added to the optical system. Realize simultaneous acquisition of remote sensing images in multiple spectral bands such as visible near-infrared, medium-wave infrared, and long-wave infrared. In particular, the infrared optical system uses a large aperture to achieve high-resolution detection, greatly improving detection capabilities. Previously, infrared cameras had a separate optical system, limited by infrared optical materials, and it was difficult to achieve large-aperture high-resolution de...

AI Technical Summary

Problems solved by technology

Previously, infrared cameras had a single optical system, limited by infrared optical materials, it was difficult to achieve large-aperture high-resolution detection, generally within the order of 300mm

Radiation calibration on orbiting satellites mainly consists of three methods: one is to use an extended area source blackbody to perform full-aperture multi-temperature point radiation calibration on it, and the calibration parameters include the thermal radiation signal of the space camera itself , the calibration accuracy is relatively low; the second is to obtain low-temperature radiation calibration signals with the help of cold black space while using the extended surface source body, and complete the radiation calibration of multiple temperature points. This method can effectively deduct the impact of thermal radiation on the camera body However, for large-aperture infrared cameras or satellites that do not have the ability to swing significantly, it is difficult to use this method for on-orbit calibration; third, when the light entrance of the black body cannot be aligned with the cold black space, the Low temperature two extended blackbody radiation source calibration methods, because the temperature of the low temperature blackbody is generally equivalent to the temperature of the camera body, it still has high thermal radiation

However, for a large-aperture optical system with multiple photosynthesis and a common aperture, none of the above radiation calibration methods can meet the calibration requirements.

Especially in order to meet the weight, power consumption, uniformity, and movement mechanism of the large surface source blackbody of the large-aperture optical system, resulting in high cost, high risk and low reliability of the calibration system

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