Aiming at the problem of long phase delay and low precision of traditional phase shift method in threedimensional（ 3D） contour reconstruction

a new high efficiency RGB Gray code encoding method is presented for phase unwrapping. Color camera is used to shoot

respectively

deformed grating image after modulation

by height information of the object

each grating phase shift π/2. RGB grayscales are projected at the maximum of the grayscale value of the sine grating to classify the stripes. The left and right views are matched according to the phase unwrapping value of the left and right images and the binocular vision principle to restore 3D outline of the model. This method reduces the number of projection fringes required for decoding to three within 64 stripes

thereby significantly improve measurement speed and precision. The method is applied to the model surface measurement and standard sphere measurement experiments. The results show that the method improves reconstruction rate and the precision is less than 0. 03 mm.