Light section can be seen as a special case of structured light imaging. In typical light section set-ups a laser line scans the scene. This laser line is observed by a high resolution color camera, where its position has to be determined with high accuracy (Fig 1). The position of the laser source with respect to the camera origin has to be known or determined online. From the deviation of the laser points with respect to the original line observed without a scanned object, the structure of the scanned object can be determined (Fig 2).
Fig 1) Scene with laser line
Fig 2) Detected laser line
Fig 3) Reconstructed hand with color texture
If the camera used for observing the laser line also offers a 2-D color image of the whole scene without the laser line being present, this information can be used as a color texture for the 3-D object (Fig. 3). As this technology requires scanning the scene, it is not suited for dynamic scenarios. In still scenarios, however, very high 3-D point accuracies can be achieved.