Researchers at the University of Science and Technology of China (USTC) have developed a compact and lightweight single-photon LiDAR system that can be deployed in the air to generate high-resolution three-dimensional images with a low-power laser. The technology could be used for terrain mapping, environmental monitoring, and object identification. To minimize such sensors’ energy consumption, USTC researchers devised a single-photon lidar system and tested it in an airborne configuration. The single-photon lidar system is made possible by detection systems that can measure the small amounts of light given out by the laser when it is reflected. The researchers had to shrink the entire LiDAR system to develop it. It works like a regular LiDAR system when sending light pulses toward its targets.
To capture the small amounts of light reflected, the team used highly sensitive detectors called single-photon avalanche diode (SPAD) arrays, which can detect single photons. To reduce the overall system size, they also used small telescopes with an optical aperture of 47 mm as receiving optics. The time-of-flight of the photons makes it possible to determine the distance to the ground, and advanced computer algorithms help generate detailed three-dimensional images of the terrain from the sensor. To validate the new system, they conducted daytime tests onboard a small airplane in Yiwu City, Zhejiang Province. In pre-flight ground tests, the LiDAR demonstrated a resolution of nearly six inches (15 cm) from nearly a mile (1.5 km). They then implemented sub-pixel scanning and 3D deconvolution and found the resolution improved to 2.3 inches (six cm) from the same distance.
More information:
https://interestingengineering.com/innovation/single-photon-lidar-china