3D full-field fringe projection measurement based on imaging view transformation

Abstract

To address the loss of measurement information caused by limitation of the field of view in fringe projection profilometry, a 3D full-field measurement based on imaging view transformation with a mirror auxiliary is proposed in this work. In this system, the principle of ideal specular reflection is applied to create a symmetrical structure between the real and virtual images for subsequent imaging view transformation. The phase of images is obtained by a multifrequency and multiple phase-shift sinusoidal fringe projection algorithm, and the real and virtual point clouds of measured objects are obtained by system calibration. The specular reflection matrix is obtained by calculating the relationship between virtual and real corner points. As a result, incomplete real point clouds can be compensated with virtual point clouds for the 3D full-field measurement by imaging view transformation. Compared to the standard ladder, the mean absolute error and the maximum relative error are 0.0706 mm and 0.9834%, respectively.