Submillimeter detector calibration with a low-temperature reference for space applications

Abstract

Infrared observations from space will involve low levels of background radiation incident on the detector. We describe a detector calibration method which uses a cold blackbody source having low background. The effective wavelength of the modulated power is determined by the mean temperature of the source since no filters are employed. Direct temperature modulation of the source eliminates the need for any chopping mechanism. Such a low‐temperature modulated source can be viewed as a low‐resolution temperature‐tuned absolute spectrometer.