Revolutionary LiDAR technology sees through fog, smoke for precise remote sensing

Interesting Engineering describes in its new article that a groundbreaking LiDAR system has been developed that could revolutionize remote sensing, security, and monitoring. 

A groundbreaking LiDAR system has been developed with the remarkable ability to see through fog and smoke, unveiling hidden objects and offering highly detailed remote sensing capabilities. This innovation holds great promise for advancing security, surveillance, and environmental monitoring.

The system is based on cutting-edge "single-photon time-of-flight" technology, enabling it to capture high-resolution 3D images of objects with incredible precision.

One of the most impressive features of this new LiDAR system is its ability to clearly capture a human face in 3D from distances of up to half a mile, showcasing its potential for advanced identification and surveillance applications.

“This type of measurement system could lead to improved security and monitoring systems that could, for example, acquire detailed depth images through smoke or fog and of cluttered scenes,” said Aongus McCarthy from Heriot-Watt University in the UK. 

“It could also enable the remote identification of objects in various environments and monitoring of movement of buildings or rock faces to assess subsidence or other potential hazards,” added McCarthy, who is the study’s first author.

LiDAR, which stands for Light Detection and Ranging, operates by calculating the time it takes for a laser pulse to reach an object and return. This time-of-flight data determines the distance to the object, and by scanning the area, a 3D image is generated.

This innovative technology employs a superconducting nanowire single-photon detector (SNSPD), an ultra-sensitive device created by MIT and NASA's Jet Propulsion Laboratory. The detector is capable of detecting individual photons, allowing the use of low-power, eye-safe lasers for quick, long-range measurements.

“Our system uses a single-photon detector approximately twice as efficient as detectors deployed in similar LiDAR systems reported by other research groups and has a system timing resolution at least 10 times better,” McCarthy explained.

“These improvements allow the imaging system to collect more scattered photons from the target and achieve a much higher spatial resolution,” McCarthy added. 

The detector was combined with additional technologies, including a custom-designed single-pixel scanning system operating at a 1550nm wavelength, along with precise timing equipment. 

The LiDAR system was field-tested at Heriot-Watt University, where measurements were taken from objects located at 45 meters, 325 meters, and 1 km away. 

To test the system’s resolution, researchers scanned a 3D target and captured images of a human face at those distances. The system was able to resolve details as small as 1 mm— a tenfold improvement in depth resolution compared to previous systems. Using an eye-safe 3.5 mW laser, the technology captured 3D images of a human face in just 1 ms per pixel at these distances.

By Naila Huseynova