
MCT (HgCdTe) photoconductive detectors have a decreasing resistance with increasing infrared light. The spectral response of HgCdTe can be changed by adjusting the stochiometry of the detector. Peak sensitivity can vary from 3.6 µm to 17 µm, while the cut-off wavelength can vary from 5.5 µm to 22 µm. The detectors can be cooled using either thermoelectric coolers, liquid nitrogen dewars and Stirling engine coolers. Custom devices are also available with different active areas and arrays with different number of elements.