What is the maximum temperature that the detector surface can reach and still maintain it photoconductive properties?
The maximum rated element temperature for PbS detectors is +65°C and for PbSe it is +55ºC. This refers to the actual temperature limits that the detector surface can reach, not temperature that radiates onto the detector. Based on our data PbS detectors are much more sensitive to temperature than PbSe detectors. There is a time vs. temperature relationship when it comes to the element degradation. For example, if the detector reaches +80°C for a few seconds, the heat will not necessarily change the detector characteristics. On the other hand, if it sits at +65ºC for an extended period of time the detector may degrade. As a general rule, we use the above stated temperatures as limits.
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