Efficient completely polarization-encoded binocular structured light 3D measurement method for metallic objects

In practical 3D measurement applications, stereo vision assisted with phase shift patterns is intensively studied and widely used for its high precision and excellent noise resilience. While aiming to improve matching efficiency, excessive projection patterns or unreliable algorithms may be introduced as a side effect. We propose a completely polarization-encoded phase shift (CPPS) method to overcome the above challenges. In our method, the Stokes parameter S1 of the polarization patterns is encoded. Compared to the traditional fringe patterns, our method can reduce the number of projected patterns to improve the measurement efficiency. Therefore, the exact constraints can be realized without additional patterns. Experimental results show that the CPPS method reduces the matching time by 76.6% while reducing the number of fringe patterns by half.