A scanning approach using fringe projection techniques for 3D profile measurements

摘要

In this paper, a scanning approach using fringe projection techniques to perform the 3D shape measurement for a complicated object is proposed. A fringe pattern is projected onto the inspected object. A CCD camera observes the projected fringes. The point of view of the CCD camera is the same as the projected fringes. Thus, shadowing caused by tilted fringe projection can be eliminated. The depth-of-field of the camera lens is short enough that only fringes within the focused area can be clearly observed. By moving the inspected object around the focused area along the depth direction, a set of images, which addresses the contour of the object with its corresponding depth, is obtained. Assembling the image contours with their corresponding depths, the 3D shape of the object is retrieved. Even though the depth discontinuity on the inspected surface is pretty high, the proposed method can retrieve the 3D shape precisely.