Vol. 45, Issue 1, pp. 51-61

Abstract

An on-line phase measurement profilometry based on improved Stoilov’s algorithm is proposed to measure the 3D shape of moving object. While only one frame sinusoidal grating is projected on the moving object, the equal phase-shifting step deformed patterns modulated by profile of the measured object can be captured at every equivalent moving distance of the measured object instead of digital phase-shifting. Stoilov’s algorithm is an equal phase-shifting step algorithm at an arbitrary phase-shifting step, which is suitable for on-line phase measurement profilometry. However, the arbitrary phase-shifting step of Stoilov’s algorithm depends on the captured deformed patterns, in which the digitized errors of digital light projector or CCD camera, and the disturbance of surrounding light could be introduced, it will lead to some abnormities in wrapped phase, such as the denominator in Stoilov’s algorithm could be zero, which could cause the reconstructed 3D profile of the measured object appear burr, distortion or aberration, even could not be reconstructed. So an on-line phase measurement profilometry based on improved Stoilov’s algorithm is proposed. The arbitrary phase-shifting step is retrieved by both pixel matching and fringe cycle calibration rather than the captured deformed patterns. Experiments verify the feasibility and effectiveness of the proposed on-line phase measurement profilometry.