Patent ID: 8026471

Claim:
A sensor comprising a plurality of pixels, wherein each pixel comprises a first photodiode comprising a first doped region having a first perimeter, wherein the first photodiode is a single-photon avalanche diode that is physically adapted to provide a current pulse in response to a single received photon; a first negative feedback element, wherein the first negative feedback element is electrically connected in series with the first photodiode, and wherein the first photodiode and the first negative feedback element are monolithically integrated such that the first negative feedback element is disposed above the first doped region and is substantially located completely within the first perimeter, and further wherein the first photodiode and the first negative feedback element collectively define a first negative-feedback avalanche diode; and a circuit comprising a counter, wherein the circuit receives current pulses from the first photodiode and provides an output signal based on the number of current pulses received from the first photodiode within a time period.