Calibration of terrestrial laser scanners

The calibration of a laser scanner is necessary to reduce systematic errors in the acquired point cloud. Furthermore, calibrating laser scanners is motivated by the need of users to access up-to-date quality information. For calibrating a terrestrial laser scanner, a functional calibration model needs to be set up. This functional calibration model is only partially comparable to the one of a total station. Complicating at setting up this complete calibration model is amongst others the fact that the manufacturers publish their calibration functions and procedures only sparsely. For calibrating a terrestrial laser scanner after delivery, the parameters of the functional calibration model can be estimated based on a self-calibration in a calibration point field. The development of an optimal calibration field has not yet been completed; its configuration is presently in the focus of several research institutions. This study gives an overview about the task of calibrating terrestrial laser scanners based on a description of laser scanner specifications, test procedures and their errors causing imperfections.