The balanced photodetector consists of two photodiodes and a differential amplifier. The two photodiodes operate in the same way, but the input light signal is in. The method of balanced photodetection (or differential photodetection) has been developed for detecting small differences in optical power between two optical input signals while largely suppressing any common fluctuations in the inputs. Figure 1: A simple electronic circuit for balanced. These are differential amplification type photoelectric conversion modules containing two photodiodes with uniform characteristics. The output is the difference of the two photocurrents, which cancels common-mode noise (laser RIN, ASE, LO amplitude fluctuations) while. Thorlabs' line of balanced photodetectors are presented here. Depending on the model, either a silicon or InGaAs detector is employed to enable detection in the UV to MIR.
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