LIDAR, an acronym of “light detection and ranging” or “laser imaging, detection, and ranging” is a method for determining ranges by targeting an object or a surface with a laser and measuring the time for the reflected light to return to the receiver. Lidar may operate in a fixed direction (e.g., vertical) or it may scan multiple directions, in which case it is known as lidar scanning or 3D laser scanning, a special combination of 3D scanning and laser scanning. Lidar has terrestrial, airborne, and mobile applications.
An animated view of 3D lidar data
LDLidar, a popular and inexpensive sensor
https://en.wikipedia.org/wiki/Lidar
[LIDAR videp] [RVIZ lidar visualization]
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