Nonuniformity correction based on the blackbody image space in uncooled long-wave infrared cameras without a shutter

Uncooled long-wave infrared detectors suffer from temperature drift and image quality degradation due to the lackof aconstant temperature environment. A shutter is commonly used to calibrate the detector periodically, but it causes wearand tear on the lens and detector, and may fail in harsh environments. This article presents a more advanced researchmethod for nonuniformity correction based on the blackbody image space in uncooled long-wave infrared cameraswithout a shutter. The proposed method integrates based on calibration and based on real time scenario non-uniformitycorrection techniques in two step: offline calibration stage builds an blackbody image space fromblackbody imagescollected at different ambient temperatures; online identification stage finds the optimal projection of the scene imageinblackbody image space using the statistical prior of the sharp real time scenario infrared image. And estimates theoptimal blackbody image for non-uniformity correction at the current ambient temperature. It creates a "virtual shutter"in front of the lens that effectively compensates for the temperature drift of the detector characteristics andlens. Comparative experiments show that the proposed method significantly reduces non-uniformity and adapts to the ambient temperature variation.