Design of readout circuit based on SPAD array and laser ranging experiments

With the continuous advancement of scientific research and the vigorous development of industrial applications, the demand for weak optical signal detection has been increasing, placing higher requirements on photodetectors. Some single-photon detectors based on photomultiplier tubes or superconducting materials face limitations in development and application due to their bulky systems, complex structures, and the need for stringent vacuum and low-temperature environments. The progress in semiconductor photodetection technology has accelerated the industrialization of single-photon detection techniques. This paper first analyzes the working principles of Single-Photon Avalanche Diode (SPAD) arrays and investigates their photon detection theory. Subsequently, front-end electronics design is conducted, leading to the development of readout circuits for SPAD array detectors. Finally, experiments are designed to measure key performance parameters, including dark count rate, response pulse width, rise time, dynamic range, etc., along with laser ranging experiments.