Calibration of a structured light system: A projective approach

We present in this paper a novel calibration method that uses cross ratio to compute world paints falling onto any given light stripe plane of a structured light system. We show that, by using 4 known non-coplanar sets of 3 collinear world points, the direct 4 x 3 image-to-world transformation matric for each light stripe plane can also be recovered from plane-to-plane homography. Preliminary experiments conducted with a calibration target and a mannequin suggest that this novel calibration method is robust and is applicable to many shape measurement tasks.