A 3-D shape measurement system using multiple light stripe active triangulation is described. The system employs a liquid crystal light valve mounted in a conventional projector to code, or label, an array of 64 stripes of light projected onto the scene to be measured. The scene is viewed by a camera displaced from the projector. Firstly the stripes are located to an accuracy of approximately 0.1 pixel in an image digitized with all the stripes turned on. The stripes are then coded by the projection of a sequence of six patterns of stripes using the light valve. In each pattern the intensity of each stripe, on or off, indicates one bit in a six bit code assigned to the stripe. Each located stripe can therefore be identified by determining the six bit number defined by its intensity in the images of the coding patterns. Once the stripes have been identified triangulation can be performed.

Date Published: 12 March 1988
PDF: 11 pages
Proc. SPIE 0850, Optics, Illumination, and Image Sensing for Machine Vision II, (12 March 1988); doi: 10.1117/12.942878

Published in SPIE Proceedings Vol. 0850:
Optics, Illumination, and Image Sensing for Machine Vision II
Donald J. Svetkoff, Editor(s)