Analysis of the relationship between fringe angle and three-dimensional profilometry system sensitivity

The relationship between projector-camera baseline and the phase variation direction of fringe patterns is one of the essential characteristics in a three-dimensional (3D) profilometry system, although it has been ignored. This paper indicates that a 3D profilometry system will be most sensitive to object depth change when the phase variation direction of the fringe patterns is parallel to the baseline, which is analyzed in systems based on both the triangulation and stereovision principles. An efficient method is proposed to achieve the most sensitivity by projecting a set of fringe patterns of different phase variation directions. Experimental results demonstrate our analysis and the proposed determination method. (C) 2014 Optical Society of America