Lidar is commonly used to make high-resolution maps, with applications in surveying, geodesy, geomatics, archaeology, geography, geology, geomorphology, seismology, forestry, atmospheric physics, laser guidance, airborne laser swathe mapping (ALSM), and laser altimetry. Lidar has terrestrial, airborne, and mobile applications. 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 3-D scanning and laser scanning. Lidar ( / ˈ l aɪ d ɑːr/, also LIDAR, LiDAR or LADAR, 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. Vegetation heights are depicted in shades of green, where dark greens are closest to the ground and light greens are the highest. For ground-level features, colours range from deep brown to tan. This visualisation shows an airplane collecting a 50 km swathe of lidar data over the Brazilian rainforest.
