Color grating projection moire with time-integral fringe capturing for high-speed 3-D imaging

We present a high-speed moire method of color grating projection, which performs phase-shifting 3-D contouring with only a single operation of fringe capturing. Three red, green, and blue pairs of projection and viewing gratings are fabricated on a single glass plate with predetermined lateral offsets. The glass plate is translated along with the color gratings during measurement at a fast speed, so that a color CCD camera simultaneously monitors three separate patterns of moire fringes with 2pi/3 phase offset. This time-integral fringe capturing enables us to obtain high-quality moire fringes with the line images of the original viewing gratings inherently removed, which leads to better measurement accuracy with less computational burden of fringe processing. (C) 2002 Society of Photo-Optical Instrumentation Engineers.