Digital fringe projection system for large-volume 360-deg shape measurement

We present a system for 3-D shape measurement in large volumes based on combined digital-fringe-Gray-code projection. With the help of a new calibration procedure, the system provides accurate results despite its crossed-axis configuration and unknown aberrations of the digital light projector and CCD camera. Also, the separate clouds of points captured from different directions are automatically merged into the main cloud. The system delivers results in the form of (x,y,z) coordinates of the object points with additional (R,G,B) color information about their texture. Applicability of the system is proven by presenting sample results of measurements performed on complex objects. The uncertainty of the system was estimated at 10(-4) of the measurement volume. (C) 2002 Society of Photo-Optical Instrumentation Engineers.