SPAD-Based LiDAR Sensor in 0.35 µm Automotive CMOS with Variable Background Light Rejection

Abstract

We present a SPAD-based LiDAR sensor fabricated in an automotive certified 0.35 µm CMOS process. Since reliable sensor operation in high ambient light environment is a crucial factor in automotive applications, four SPADs are implemented in each pixel to suppress ambient light by the detection of photon coincidences. By pixel individual adjustment of the coincidence parameters to the present ambient light condition, an almost constant measurement performance is achieved for a wide range of different target reflectance and ambient illumination levels. This technique allows the acquisition of high dynamic range scenes in a single laser shot. For measurement and demonstration purpose a LiDAR camera with the developed sensor has been built.

Keywords

• light detection and ranging (LiDAR)
• single-photon avalanche diode (SPAD)
• range imaging
• time-of-flight (TOF)
• background rejection
• photon coincidence