Real-time 3D imager based on spatio-temporal phase unwrapping

In this paper, we propose a novel 3D measurement system, which consists of 1) spatially phase-modulated light, which have a single frequency for time but have different phase according to the projection angle, and 2) the correlation image sensor (CIS), which generates temporal correlations between light intensity and three external reference signals on each pixel. Within a frame, amplitude and phase of the light are demodulated by the CIS. Then, the projection angle map is obtained based on spatio-temporal phase unwrapping method we propose. We implemented this system using our CMOS 200 /spl times/ 200 pixel CIS, and successfully reconstructed the range map in real time.