I am currently using an InGaAs array and would like to look at switching to a PbS array. What is the quantum efficiency of a PbS array?
Typically photoconductive detectors (PbS) are not characterized by quantum efficiency because, theoretically, they are completely efficient (100% QE), unlike photovoltaic detectors (InGaAs). A better way to compare PbS and InGaAs arrays is with detectivity (D*), which is really normalized signal to noise ratio. Generally, PbS detectors have slightly better detectivity than extended InGaAs detectors. However, if you are looking at shorter wavelengths (<1.7µm), standard InGaAs tends to have a higher D* value than PbS.
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