3D shape measurement in the presence of strong interreflections by epipolar imaging and regional fringe projection

A 3D shape measurement method in the presence of strong interreflections is presented. Traditional optical 3D shape measurement methods such as fringe projection profilometry (FPP) cannot measure regions that contain strong interreflections, which result in 3D shape measurement failure. In the proposed method, epipolar imaging with speckle patterns is utilized to eliminate the effects of interreflections and obtain the initial 3D shape measurement result. Regional fringe projection based on the initial measurement result is further applied to achieve high-accuracy measurement. Experimental results show that the proposed method can measure the regions that contain strong interreflections at a high accuracy.