All-Digital Imaging based on Photon Counting : A Decade of CMOS single-photon image sensors(Workshop on microscopy, biology, medicine, and advanced CMOS imagers)

Abstract

Single-photon detection enables a new type of sensor capable of massively parallel conversion of photons onto digital signals that can be readily processed and/or transmitted 'raw' with virtually no loss. The similarity with conventional cameras, except for photon-counting capability, is staggering; however several properties makes these sensors different from conventional ones. For one, a massively parallel time stamping capability enable time-correlated single-photon techniques to be implemented in a compact and relatively inexpensive way. Moreover, the lack of readout noise and the digital nature of the sensors make them appropriate for in situ processing so as to potentially reduce data transfer to and from the camera. Finally, the sensors are indicated for detection and processing of ultra-fast and complex photonic events, often present in biomedical imaging systems; they are also robust, often enabling unprecedented accuracy in a number of imaging modalities. This paper describes several image sensors designed to efficiently process large data volumes, so as to minimize power dissipation, improve flexibility, and shorten overall time-to-market.