Patent attributes
Technologies are described for methods and systems effective to detect photon receiving events. A first comparator may compare a magnitude of a photon signal to a first threshold voltage to produce a first output. A second comparator may compare the magnitude of the photon signal to a second threshold voltage to produce a second output. A counter control circuit may increment a second counter in response to a determination that the magnitude of a first peak of the photon signal exceeds and then falls below the second threshold voltage. The counter control circuit may prevent a third counter from incrementing in response to a second peak of the photon signal. The counter control circuit may increment the first counter in response to the magnitude of the signal exceeding and then falling below the first threshold voltage. The first counter may be associated with a number of photon receiving events detected.
