High accuracy contouring using projection moiré

Shadow and projection moiré are the oldest forms of moiré that were used in actual technical applications (first paper on this subject published in 1929). In spite of this fact and the extensive number of papers that have been published on this topic the use of shadow moiré as an accurate tool that can compete with alternative devices poses very many problems that go to the very essence of the mathematical models used to obtain contour information from fringe pattern data. In this paper some recent developments on the projection moiré method are presented. Comparisons between the results obtained with the projection method to the results obtained by mechanical machines that operate with contact probes are presented. These results show that by using projection moiré it is possible to achieve the same accuracy that current mechanical touch probe devices provide.