For our testing, we use a voltage divider bias circuit with a load resistor set at either 1 Megohm or set at a resistance equal to the dark resistance of the detector. The opamp can be nearly [...]
The detector has a 1/f noise characteristic, so the lower frequencies have higher noise and consequently a lower D* value. The signal level stays relatively constant as the chopping frequency is [...]
Can the detectors be used without a chopper if used to measure the radiation of a pulsed laser beam?
The detectors do not require a chopper. A chopper is often used to modulate the source, allowing band limited amplification of the signal and thereby increasing the signal/noise ratio. If the [...]
As the detector operating temperatures decreases, the detectivity, responsivity, and spectral response improves. Source (with permission to reproduce): http://optodiode.com/resources.html
(Note: These specifications are approximate figures that provide data for a general comparison). Temperature Parameter InGaAs (std.) InGaAs (ext.) PbS PbSe 300°K λ range (µm) 0.7 – 1.7 1.2 [...]
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 [...]
Yes, as long as the pulse width of the laser is long enough, the wavelength is in the correct range, and the power density is within limits. Please note the detector time constant of the model [...]