Typical linear lidar systems repeatedly fire a single beam, each time measuring a single location on the ground. They collect data at a given resolution, which is also the processing resolution. By contrast, a Geiger-mode system is an array that illuminates a large area on the ground, capturing the elevation of each point, and the processing later determines the output resolution.
According to Mark Romano, geospatial product manager for Harris Corporation, Geiger-mode lidar is “a completely different technology type” from linear lidar. He says it enables much higher and faster collection flights and much higher resolutions than typical current linear systems.
Harris’ system has an array of 32 x 128 pixels (for a total of about 4,100 pixels) and flashes 50,000 times per second. “So, we are really over-sampling the area,” says Romano. The output resolution could then be, for example, 2, 8, 20, or 100 points per square meter (ppsm).
Harris has been selling Geiger-mode lidar to the military for about 16 years, gaining experience in designing and fielding sensors and supporting them in theater environments.