A 220 M-Range Direct Time-of-Flight 688 × 384 CMOS Image Sensor with Sub-Photon Signal Extraction (SPSE) Pixels Using Vertical Avalanche Photo-Diodes and 6 KHz Light Pulse Counters

We have developed a direct time-of-flight (TOF) 220 m ranging CMOS image sensor (CIS) based on a 688 × 384 pixel array of vertical avalanche photodiodes. An area scene at 220 m ahead can be ranged and imaged by one high power light pulse illuminated through diffusing (without scanning) optics and sub-photon level signals are extracted by in-pixel pulse count circuits. Depth map imaging with a 10 cm lateral resolution and with a 30 cm depth precision is realized from 1 m to 220 m range. The developed direct-TOF CIS with SPSE is expected to supersede the insufficient resolution of the conventional light detection and ranging (LiDAR) systems and the short range of indirect CIS TOF.