Patent ID: 10834345

Abstract:
An imaging device may include an active silicon photomultiplier and associated temperature and non-uniformity compensation circuitry configured to mitigate temperature and process variations on the device. The compensation circuitry may include a reference silicon photomultiplier, a constant current source that supplies a fixed current into the reference silicon photomultiplier, a voltage sensor for detecting a voltage output from the reference silicon photomultiplier, a data converter for converting the voltage output from the voltage sensor, and a voltage controller for generating an adjustable voltage for biasing the active silicon photomultiplier depending on the signal output from the data converter. The active silicon photomultiplier may include multiple illuminated microcells covered by microlenses, whereas the reference silicon photomultiplier may include multiple dark microcells distributed among the illuminated microcells to help account for non-uniformities in microcell performance across the imaging device.