Design and application of high-precision calibration blackbody for space optical remote sensing sensor

Radiation calibration is a crucial step in producing high-quality images for spaceborne infrared cameras. Blackbody radiation sources, as the standard equipment for infrared thermometers, play an increasingly important role in radiation calibration. But as the camera aperture increases, blackbody faces challenges such as poor temperature uniformity, slow heating and cooling rates, large mass, and large volume. This article proposes a design scheme for spaceborne calibration blackbody based on a combination of rope pull fixation and limit block positioning. The temperature uniformity, temperature stability, temperature rise and fall rate, thermal stress characteristics, and anti-emission vibration characteristics of the blackbody under this scheme are analyzed and optimized in detail. The analysis results show that the conduction thermal resistance between the blackbody and the environment is nearly two orders of magnitude higher than that of the conventional scheme. The blackbody has excellent temperature uniformity, temperature stability, wide calibration temperature range, light weight, small volume, and fast temperature rise and fall speed. The blackbody scheme with a thickness of only 1.5 mm was implemented and applied on orbit.