LiDAR is an abbreviation of „Light Detection and Ranging”, which explains its use – it is a method of establishing distances between objects with use of light.
For studies in this technology laser scanners are used. They are technologically advanced, modern devices. A laser scanner is, at the same time, an emitter and a receiver of a light impulse. The impulse reflects from a target, which is being scanned. Scanner measures “time of flight” of the light beam and this way establishes distance to target. During a scanning session millions of such impulses are being sent. Together they form a digital point cloud spread at different distances from the scanner. The point cloud is a three-dimensional representation of the scanned object, which can be used for different kinds of analyses.
In geography LiDAR is most often used to create maps of terrain elevation. A scanner mounted on an airplane scans the surface of the Earth and creates its three-dimensional image, which corresponds to the topography. Moreover, laser scanning finds application in other fields where precise 3D models are important, for example design or heritage preservation.