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A method and system for full-field fringe-projection for 3-D surface-geometry measurement, referred to as “triangular-pattern phase-shifting” is disclosed. A triangular grey-scale-level-coded fringe pattern is computer generated, projected along a first direction onto an object or scene surface and distorted according to the surface geometry. The 3-D coordinates of points on the surface are calculated by triangulation from distorted triangular fringe-pattern images acquired by a CCD camera along a second direction and a triangular-shape intensity-ratio distribution is obtained from calculation of the captured distorted triangular fringe-pattern images. Removal of the triangular shape of the intensity ratio over each pattern pitch generates a wrapped intensity-ratio distribution obtained by removing the discontinuity of the wrapped image with a modified unwrapping method. Intensity ratio-to-height conversion is used to …