Integration Time and Time-Bin Width in Ranging Histograms for a Photon-Counting LiDAR

High-performance light detection and ranging (LiDAR) modules are highly demanded for advanced driving assistance system and autonomous driving. With CMOS-fabricated single-photon avalanche diodes (SPADs) and pulsed-operated semiconductor lasers, photon-counting based vehicle LiDARs are one of the most promising candidates for low-cost solution. The high data rate and the long integration time of SPAD LiDARs are two of main obstacles for realizing commercially affordable 3-D imagers. In this work, we develop an evaluation method for the minimum ranging time and investigate the time-bin width effect on the ranging precision. A simple formula for predicting the shortest integration time is proposed and compared with the experimental data. We also demonstrate that a proper time-bin width can reduce the data rate and required memory size without degrading the distance resolution. Our work paves the way for making low-cost vehicle LiDARs through system optimizing and engineering.