Abstarct of [CP14]

Paveleva D., Antal Á.

Projection Color Moiré Technique for 3-D Surface Reconstruction

Proceedings of the fifth conference on mechanical engineering, May 25-26, 2006. Budapest

Moiré phenomenon, problem of ambiguities, projection technique

Moiré effect is an optical phenomenon that occurs in consequence of the coincidence of two periodical structures, gratings. Nowadays the moiré effect is used for contour generation of three-dimensional objects and measurements of deformation: strain analysis, linear or angular displacements and vibration analysis. Projection moiré method is a typical method for three-dimensional measurements. To find the absolute order of a fringe (z-coordinate of the object under research) one must define the difference in depth between two points by the moiré patterns. But to present day for extraction of an object’s three-dimensional information several moiré patterns and image processing methods such as Fourier-transform method, temporal phase shifting technique were needed, since from one moiré image it’s impossible to determine whether the object is concave or convex. It means that it was impossible to work with dynamic objects in real-time operation mode. Here we present color moiré projection technique that resolves the arising problem of ambiguities in moiré patterns by application of only one moiré pattern. This method is based on application of color rulings to gratings in projection moiré technique.