Shifting to a longer wavelength that’s safer for the eye lets Luminar raise its lidar power enough to stretch its range beyond 200 meters. Other innovations could cut system costs.
Current automotive lidars scan their surroundings by firing pulses from semiconductor diode lasers emitting at 905 nanometers in the near infrared and recording reflected light to build up a point cloud mapping the car’s surroundings. But laser-safety rules in the U.S. and other countries restrict the power in the laser pulse, limiting the lidar’s range to 30 to 40 meters, too short a distance for a car to stop safely at highway speeds. Makers of autonomous cars need to spot low-reflectivity objects at least 200 meters away to give the car enough time to identify hazards and stop, so they turned to other technologies. At least one lidar maker, however, kept tinkering.
Read the rest of “Under the Hood of Luminar’s Long-Reach Lidar” from the original source: IEEE Spectrum Cars That Think.