Flexible Multi-Camera Optical Surface Digitization System

Development of the flexible multi-camera optical surface digitization system which projects non coherent coded light in two perpendicular directions is presented. By the introduction of the absolute method for stereopairs indexing the need for twofold searching through the phase images is eliminated, as well as the influence of discontinuitics. Critical areas responsible for outlier generation are eliminated prior to triangulation by combining the modulation filtering of phase images and gradient filtering of the absolute phase images. Sequential triangulation process enabled triangulation of points that are not visible in all the cameras, thus providing means for digitization of partially occluded areas. Free form calibration object eliminated the need for specialized planar calibration objects, which combined with variable external camera parameters resulted in a system that can be adjusted depending on the measurement problem. In comparison to the commercial single and stereo camera systems our approach reduces the number of projections for the digitization of the complete objects.