CMOS imager based on single photon avalanche diodes

In this paper we report on a 32×32 optical imager based on single photon avalanche diodes integrated in CMOS technology. The maximum measured dynamic range is 120dB and the minimum noise equivalent intensity is 1.3×-3lx. The minimum integration time per pixel is 4μs. The output of each pixel is digital, thereby requiring no complex read-out circuitry, no amplification, no sample & hold, and no ADC.