title: Spatiotemporal approach for real-time absolute shape measurements by use of projected fringes.
abstract: 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.
authors.affiliation: Division of Experimental Mechanics, Luleå University of Technology, SE-971 87 Luleå, Sweden.
authors.forename: Lars
authors.initials: L
authors.lastname: Kinell