A combination of phase-shift with gray-code light projection into a three-dimensional vision system based on the projection of structured light is presented. The gray-code method is exploited to detect without ambiguity even marked surface discontinuities, whereas the phase-shift technique allows the measurement of fine surface details. The system shows excellent linearity. An overall mean value of the measurement error equal to 40 μm, with a variability of approximately ∓35 μm, corresponding to 0.06% of full scale, has been estimated. The implementation of the technique is discussed, the analysis of the systematic errors is presented in detail, and the calibration procedure designed to determine the optimal setting of the measurement parameters is illustrated.
© 1999 Optical Society of America
(120.0120) Instrumentation, measurement, and metrology : Instrumentation, measurement, and metrology
(120.2830) Instrumentation, measurement, and metrology : Height measurements
(120.3930) Instrumentation, measurement, and metrology : Metrological instrumentation
(150.0150) Machine vision : Machine vision
(150.6910) Machine vision : Three-dimensional sensing
Giovanna Sansoni, Matteo Carocci, and Roberto Rodella, "Three-Dimensional Vision Based on a Combination of Gray-Code and Phase-Shift Light Projection: Analysis and Compensation of the Systematic Errors," Appl. Opt. 38, 6565-6573 (1999)