Calibrating a structured light stripe system: A novel approach

The problem associated with calibrating a structured light stripe system is that known world points on the calibration target do not normally fall ont o every light stripe plane illuminated from the projector. We present in th is paper a novel calibration method that employs the invariance of the cros s ratio to overcome this problem. Using 4 known non-coplanar sets of 3 coll inear world points and with no prior knowledge of the perspective projectio n matrix of the camera, we show that world points lying on each light strip e plane can be computed. Furthermore, by incorporating the homography betwe en the light stripe and image planes, the 4 x 3 image-to-world transformati on matrix for each stripe plane can also be recovered. The experiments cond ucted suggest that this novel calibration method is robust, economical, and is applicable to many dense shape reconstruction tasks.