Onboard calibration device based on variable temperature blackbodies

Abstract

The invention relates to an onboard calibration device based on variable temperature blackbodies, which is used for carrying out onboard radiant calibration on a spaceborne infrared camera. A low-temperature blackbody adopts a semiconductor refrigerator for refrigeration, and heat generated by the semiconductor refrigerator is radiated through radiation of a low-inertia and dynamic-balance fan-shaped swing arm. A high-temperature blackbody adopts an electrical heater for heating. Temperatures of the high-temperature blackbody and the low-temperature blackbody can be adjusted within a certain temperature range, and can be set according to needs. When onboard radiant calibration needs to be carried out on the infrared camera, a stepper motor sequentially switches the high-temperature blackbody and the low-temperature blackbody to the light path via the fan-shaped swing arm and switched out after calibration is over. The onboard calibration device adopts the low-temperature blackbody by using the semiconductor for refrigeration, thereby expanding the calibration temperature range. Temperatures of the high-temperature blackbody and the low-temperature blackbody are variable, proper temperatures of the high-temperature blackbody and the low-temperature blackbody can be set according to the temperature range of an observed scene, thereby improving the calibration precision.

Description

technical field [0001] The invention belongs to the technical field of satellite optical remote sensors, and relates to an on-board calibration device based on a variable temperature black body, which is used for on-board radiation calibration of a space-borne infrared camera. Background technique [0002] After the spaceborne infrared camera is launched into orbit, its performance will change due to factors such as the space environment and its own aging. In addition, the response non-uniformity and time-dependent changes of each detector element of the spaceborne infrared camera will affect the imaging quality. If on-orbit radiometric calibration is not performed, image applications will be affected. There are many methods of on-orbit calibration, including cross-calibration, substitutional calibration, and on-board calibration using a camera-carried calibration device. Each calibration method has its advantages and limitations. For infrared cameras with larger apertures,...

AI Technical Summary

Problems solved by technology

Judging from similar loads at home and abroad, the current on-board calibration high and low temperature black bodies used in space-borne infrared cameras are usually set at a fixed temperature point, which limits the temperature range that can be calibrated, resulting in low radiation calibration accuracy, which is difficult to satisfy users. Increasingly stringent quantitative use requirements for remote sensing data

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