Single-photon Avalanche Photoelectric Diode Test System Based On FPGA

Single-photon detector is a photoelectric conversion device with ultra-high sensitive properties,which has already been applied in many fields such as quantum information,biological detection,free space optical communication,long distance laser ranging,laser radar,and astronomical observation.At present,photomultiplier,vacuum avalanche photodiode,superconducting single photon detector,and avalanche photodiode are the most popular single photon detectors.Detection efficiency,dark count,after pulse and dead time are the key parameters used to describe the performance of the single photon detector.The calibration of these parameters can provide important reference for the researching and applying information of the single photon detector.Therefore,the calibration of single photon detector became an important issue in the research and application of the single photon detection.Now there is no integrated circuit solution for the calibration of single photon detector.Most single-photon detectors are calibrated by a discrete series of test instruments,such as regulated power supplies,signal generators,photon counters,and so on,which is not a portable.It is not in accordance with the miniaturization and integration of detector system.Once different types of detectors are calibrated,different test circuits must be redesigned.The traditional calibration method of the single-photon detector is of high complexity and cannot guarantee the identical system structure of each calibration.Accordingly,the actual calibration efficiency is low,and the calibration result is not extremely stable,which greatly limit the development of the detectors.In this paper,we proposed a single-photon avalanche diode calibration system based on FPGA instead of the general instrument.This system was compatible with various avalanche quenching modes which are active quenching,passive quenching and gated Geiger mode.It can realize the calibration of key performance parameters such as detection efficiency,dark count,after-pulse,etc.The calibration system can be controlled by computer visual interface.The reverse bias voltage of avalanche photodiode,the discriminate level of the avalanche signal,dead time,detection frequency and the repetition frequency of laser can be adjusted by the visual interface through the FPGA.The FPGA can also collect and count the avalanche signals,which greatly improves the integration performance of the calibration system.In addition,we demonstrated the calibration of silicon avalanche photodiode and indium gallium arsenic/indium phosphor avalanche photodiode in our experiment through the calibration system based on FPGA.The result showed that we provide a convenient and integrated solution for the single photon detector's performance calibration,which is beneficial to promote the development and applications of single photon avalanche photodiode.