Chinese LiDAR system could recognize a face from space

Chinese scientists have developed laser-imaging technology sufficiently powerful to capture face biometric details from more than 60 miles (100 kilometers) away. How far is that? Well, far enough to be in space as the breakthrough imaging technology could be deployed in a satellite.

Researchers at China’s Academy of Sciences’ Aerospace Information Research Institute tested a new synthetic aperture LiDAR (SAL), a laser radar that can create 2D or 3D images, the South China Morning Post reports (via LiveScience). The tests were conducted across Qinghai Lake, which is a very large lake in northwest China.

SAL uses optical wavelengths to produce finer images compared to microwave radiation, which previous SAR systems relied on (although microwaves can penetrate materials), and results in higher resolution images. The test targeted arrays of reflective prisms that were 63.3 miles (101.8km) away from the LiDAR system, with the equipment able to detect details as small as 1.7 millimeters and with distances measured to within 15.6mm.

The laser-based system could potentially allow China to inspect foreign military satellites with enormous precision, according to SCMP. It could also recognize faces from low-Earth orbit such is the distance and resolution it is capable of. However, the tests took place during weather conditions that were close to perfect since cloud cover and other visibility impairments could significantly affect the system’s effectiveness.

This is in contrast with another LiDAR system that can ID a face from a kilometer away. This superconducting LiDAR system was developed by researchers at Heriot-Watt University along with scientists at NASA, MIT, and the University of Glasgow. The superconducting creation, which requires cooling, can trace a single photo to an accuracy of 13 picoseconds (13 trillionths of a second) and can see through fog and smoke.

The system was tested at 45 meters, 325 meters and one kilometer and could capture an image of a person with astonishing detail. While the team wants to explore the capabilities at even greater distances, there is some way to go to match the 100 kilometers of the LiDAR developed by the Chinese scientists.

Both systems have their pros and cons, with the Heriot-Watt system able to see through fog and smoke (although the system requires cooling to minus 272 Celsius), while the Chinese one relies on optimal weather conditions although it can capture an image from much farther away.

The findings of the Chinese system can be found in a new study published in the Chinese Journal of Lasers, Issue 52, Volume 3.

Article Topics

biometric identification  |  biometrics  |  China  |  facial recognition  |  LiDAR  |  long-distance  |  research and development