A spatiotemporal approach for fast absolute shape measurements is formulated. In principle, the Takeda method is used in combination with the reduced temporal phase-unwrapping scheme to calculate the absolute phase. Three different measurements are performed: a flat surface, steps, and a curved beam with varying cross sections. The performance in standard deviation is improved, and the success rate is approximately the same as that obtained with a strict temporal solution for which a four-bucket phase algorithm is used. The multichannel approach is also used. Then only one static image is needed. It should therefore be possible to measure objects in motion.
© 2004 Optical Society of America
(100.0100) Image processing : Image processing
(120.0120) Instrumentation, measurement, and metrology : Instrumentation, measurement, and metrology
(120.2650) Instrumentation, measurement, and metrology : Fringe analysis
(150.0150) Machine vision : Machine vision
(150.6910) Machine vision : Three-dimensional sensing
Lars Kinell, "Spatiotemporal Approach for Real-Time Absolute Shape Measurements by Use of Projected Fringes," Appl. Opt. 43, 3018-3027 (2004)