Static and dynamic features of Fourier transform profilometry: A review

Fringe projection techniques are very popular among the several profilometry methods proposed in literature. One of their main advantages is that most of them require one image of the object to retrieve its surface. From a theoretical point of view these techniques are based on a simple mathematical model which is at the base of the conversion of the measured quantity (usually the phase map of the image of the grid projected onto an object surface) into the height distribution of the object. However, the practical implementation of the system is not an easy task to be achieved. The mathematical models are often a simplification of the reality and it is valid only under some conditions. These discrepancies between the theory and the practice deal to a series of discussions about the quality of the measure of fringe projection techniques. This paper proposes a wide argumentation about the measurement uncertainty and the source of error which is influenced by. After a concise description of the triangulation model and of the basic idea of the system working, the measurement techniques are analyzed both from a static and a dynamic point of view, with a special attention to the uncertainty sources in the two measurement conditions and the possible improvements that may be applied to reduce their influence.