What is the spectral response of your detector?
Spectral response defines the sensitivity of a detector to radiation at a various wavelengths. PbS detectors are sensitive in the 1-3µm region and PbSe detectors are sensitive in the 1-5.5µm region. Cooling the detector shifts the spectral response of PbS and PbSe detectors to longer wavelengths. Please refer to Section 3 of our detector technical notes for a graph of detectivity vs. wavelength at different temperatures.
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