Radiometric calibration of a longwave FPA camera for IR scene projector characterization

摘要

We present radiometric calibration methods and data for a HgCdTe longwave IR focal plane array camera that will be used for nonuniformity correction and calibration of an ambient-background IR scene projector at the Johns Hopkins University Applied Physics Laboratory. Reported results include spectral response, responsivity (in terms of radiance), and non-radiometric measurements important in the IRSP NUC process. Uncertainty sources and estimates are discussed as they apply to this problem. We found that a responsivity measurement should be performed each time the camera is powered on, and that drift in the output signal stabilizes within about an hour. Even after waiting an hour, it may be necessary to measure a blackbody source periodically during IRSP calibration to ensure that camera drift does not skew the results.