To this end a laser line (laser light section) is projected onto the object and is observed by a matrix camera at a specific angle (triangulation). Height differences of the object along the laser line become visible as displacement on the camera sensor; this displacement is calculated into a relative height profile. While the object moves under the laser triangulation measuring head, numerous height profiles are generated which are consequently assembled into a 2.5D image (range map); this scan method is in principle comparable to a line scan camera that generates 2D images by recording individual lines. From the 2.5D images, metrically calibrated 3D images (cloud of points) can be calculated through suitable algorithms. These 3D images can be further processed with specific 3D tools (e.g. Match 3D, plane fit, determination of regular geometries).
Laser triangulation is especially suitable for continuously moving objects on a production line. For reproducible results, optically cooperative – e.g. matt or non-transparent – surfaces are ideal; differences in colour barely influence the process.
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