title: Three-dimensional profiling with binary fringes using phase-shifting interferometry algorithms.
abstract: Three-dimensional shape measurements by sinusoidal fringe projection using phase-shifting interferometry algorithms are distorted by the nonlinear response in intensity of commercial video projectors and digital cameras. To solve the problem, we present a method that consists in projecting and acquiring a temporal sequence of strictly binary patterns, whose (adequately weighted) average leads to a sinusoidal fringe pattern with the required number of bits. Since binary patterns consist of "ones" and "zeros"--and no half-tones are involved--the nonlinear response of the projector and the camera will not play a role, and a nearly unit contrast gray-level sinusoidal fringe pattern is obtained. Validation experiments are presented.
authors.affiliation: Instituto de Física, Facultad de Ingeniería, UdelaR, J. Herrera y Reissig 565, Montevideo, Uruguay.
authors.forename: Gastón A
authors.initials: GA
authors.lastname: Ayubi
authors.forename: J Matías
authors.initials: JM
authors.lastname: Di Martino
authors.forename: Julia R
authors.initials: JR
authors.lastname: Alonso
authors.forename: Ariel
authors.initials: A
authors.lastname: Fernández
authors.forename: César D
authors.initials: CD
authors.lastname: Perciante
authors.forename: José A
authors.initials: JA
authors.lastname: Ferrari