3D measurement technology based on binocular vision using a combination of gray code and phase-shift structured light

3D surface measurement using binocular stereo vision technology and a coded structured light which combines Gray code with phase-shift is studied in this paper. The accuracy of 3D measurement mainly depends on the decoding of Gray code views and phase-shift views. However, it is difficult to threshold Gray code views because of the different albedos on regions of surface and interreflections on the surface. Therefore, after projecting Gray code patterns, their inverses are projected. A new method is proposed to solve the problem of period dislocation between Gray code and phase-shift in course of decoding. The experiment of the surface measurement of a human eye plaster model is used to test our 3D measurement method, and reconstruction results show the accuracy and reliability of our method.