Beschreibung
At this time, the first measuring systems which are based on the principle of the continuous modulation interferometry, also known as phase-depending or indirect time of- flight measurement, are leaving the laboratories and become an interesting alternative to established classical measurement principles, like triangulation or stereo-vision. Based on this acquisition method of the third dimension many measuring tasks can be solved easily that have been put up with numerous disadvantages in the past resulting in great efforts. In respect to this disadvantages, the reference is made to the stereo-vision approach whereas a huge amount of computing power is necessary determine the disparity map. Furthermore, this approach calls for the detection of the required feature points in both images. Disadvantages, as already described in the paragraph before, don’t apply on the measurement systems based on time-of-flight approach. However, these systems are subjected to other limitations caused by the underlying measurement principle itself and whose implementation results in measurement errors and ‑variations. The mathematical basics and the corresponding physical model are given to derive the errors and to develop adequate correction and calibrations methods. In addition, there are other mainly external effects that corrupt the measured distance: the geometry of the regarded scene itself. In this context, two possible reasons or rather triggers have to be divided: on one hand multi-reflections within the scene and on the other hand, reflections caused by objects that are located in minor distance to the measurement system within its path of rays. These causes will be named stray light in the following. For the first case, merely an estimation of the measurement error can be done using a simulation approach. Contrary to this, the error in the second case can safely be calculated by the information (distance and amplitude) that can be extracted from a taken shoot of the regarded scene. The design of an appropriate method for compensation of the measurement error in the second case is taken center stage of this thesis. The designed method based on simplified scenes, generated in the laboratory, is validated on real scenes. The validation and verification of this method is confirmed by the use of established statistical tools.