Long-range single-pixel LiDAR 3D imaging technology research

Lidar three-dimensional measurement technology is a three-dimensional spatial perception technology that has received extensive attention in recent years. Currently, the mainstream commercial lidars generally perform three-dimensional imaging for close-range scenarios (10-200m). To achieve three-dimensional imaging of distant targets, this paper proposes and experimentally validates a lidar three-dimensional measurement system based on a digital micromirror device (DMD) and a single-pixel detector. This system uses a short-pulse laser source and a dual-channel avalanche photodiode (APD), and spatially encodes the target scene using the Hadamard mode. During the signal acquisition stage, the DMD divides the echo signal into two complementary encoded reflection beams, and two APDs simultaneously detect each of them. The two detection signals correspond to the current mode and its complementary mode, and the system calculates the difference value in real time and performs calculation to effectively suppress background noise. It has been verified that the system successfully reconstructed a 64×64pixel resolution three-dimensional scene within a range of 4.3 kilometers and 6.3 kilometers. The experimental results show that this method realizes three-dimensional imaging of distant targets based on the pulse flight time and single-pixel imaging principle, providing a feasible solution for three-dimensional imaging of long-distance lidar.