Researchers led by Susumu Noda from Kyoto University in Japan have published a study on their latest nonmechanical 3D lidar system. The system matches within the palm of the hand and is able to measuring the gap of poorly reflective objects and mechanically tracking their motion.

The research was published in .

Combining Scanning and Flash Illumination

In line with Noda, “With our lidar system, robots and vehicles will give you the chance to reliably and safely navigate dynamic environments without losing sight of poorly reflective objects comparable to black metallic cars.” He added that incorporating the technology into cars would make autonomous driving safer.

The brand new system is made possible by a singular light source called a dually modulated photonic-crystal laser (DM-PCSEL). The DM-PCSEL integrates non-mechanical, electronically controlled beam scanning with flash illumination utilized in flash lidar to amass a full 3D image with a single flash of sunshine. This light source is chip-based and will eventually enable the event of an on-chip all-solid-state 3D lidar system.

Lidar systems map objects by illuminating them with laser beams and calculating the gap of those objects by measuring the time of flight (ToF) of the beams. Most existing and under-development lidar systems depend on moving parts, making them bulky, expensive, and unreliable. Flash lidar systems, however, use a single broad and diffuse beam of sunshine to concurrently illuminate and evaluate the distances of all objects in view. Nonetheless, flash lidar systems can’t measure the distances of poorly reflective objects and are likely to be large due to external lenses and optical elements required to create the flash beam.

Developing the Recent Light Source

To beat these limitations, the researchers developed the DM-PCSEL light source, which has each flash illumination and beam-scanning capabilities. The researchers incorporated this light source right into a 3D lidar system, allowing for simultaneous measurement of many objects with wide flash illumination and selective illumination of poorly reflective objects with a more concentrated beam of sunshine. Additionally they installed a ToF camera and developed software for automatic tracking of the motion of poorly reflective objects using beam-scanning illumination.

“Our DM-PCSEL-based 3D lidar system lets us range highly reflective and poorly reflective objects concurrently,” said Noda. “The lasers, ToF camera, and all associated components required to operate the system were assembled in a compact manner, leading to a complete system footprint that’s smaller than a business card.”

The researchers demonstrated the system through the use of it to measure the distances of poorly reflective objects placed on a table in a lab. Additionally they showed that the system can recognize and track the movement of those objects. The researchers are actually exploring the potential of the system in practical applications, comparable to the autonomous movement of robots and vehicles, and are investigating the opportunity of replacing the ToF camera with a more optically sensitive single-photon avalanche photodiode array for longer-distance measurements.