Researchers at the University of California-Berkeley are developing a 3-D imaging technology that can remotely sense objects across distances as long as 30 feet, 10 times farther than what can be done with comparable current low-power laser systems.
"While meter-level operating distance is adequate for many traditional metrology instruments, the sweet spot for emerging consumer and robotics applications is around 10 meters," according to researcher Behnam Behroozpour. "This range covers the size of typical living spaces while avoiding excessive power dissipation and possible eye safety concerns."
The researchers applied frequency-modulated continuous-wave (FMCW) technology to shrink the size and power consumption of today’s typical LIDAR (Light Radar) system without compromising their performance in terms of distance.
LIDAR systems emit laser light that hits an object, and then can tell how far away that object is by measuring changes in the light frequency that is reflected back. Current lasers used in high-resolution LIDAR imaging can be large, power-hungry and expensive.
The Berkeley team in their prototype system exploited MEMS tunable VCSELs to amplify the system's signal without an expense of power.
"Generally, increasing the signal amplitude results in increased power dissipation," said Behroozpour. "Our solution avoids this tradeoff, thereby retaining the low power advantage of VCSELs for this application." The team's next plans include integrating the VCSEL, photonics and electronics into a chip-scale package.
The Berkeley team will present their achievement titled "Method for Increasing the Operating Distance of MEMS LIDAR beyond Brownian Noise Limitation," at the Conference on Lasers and Electro-Optics held June 8-13 in San Jose, Calif.