Parallel three-dimensional sensing by color-coded triangulation.
We discuss a three-dimensional sensor that combines coded illumination and triangulation. The sensor supplies the distance of ~ 250,000 object pixels (TV format) in 40 ms (one single TV frame period). Themethod is based on the following principle: a color spectrum of a white-light source is imaged onto the object by illumination from one certain direction. The object is observed by a color TV camera from a direction of observation, which is different from the direction of illumination. The color (hue) of each pixel is a measure of its distance from a reference plane. It can be evaluated by the three (red-green-blue) output channels of the CCD camera. This evaluation can be implemented within TV real time. Even colored objects can be measured. The resolution achieved is 50-150 depth steps.