Improving the accuracy performance of phase-shifting profilometry for the measurement of objects in motion

This Letter presents a new approach to reducing the errors associated with the shape measurement of a rigid object in motion by means of phase-shifting profilometry. While the work previously reported is only valid for the case of two-dimensional (2-D) movement, the proposed method is effective for a situation in which the object moves in a three-dimensional (3-D) space. First, a new model is proposed to describe the fringe patterns reflected from the object, which is subject to 3-D movement. Then, an iterative least-squares algorithm is presented to estimate the phase map. Experiments show that, in contrast to conventional phase-shifting profilometry, the proposed method is capable of significantly reducing the error caused by the 3-D movement of the object.