Moiré topography by means of a grating hologram.

A new method of moire topography is described. This encompasses two processes: recording of the deformed grating projected onto a 3-D object, and posterior development of contour moire from the record. The development of contour moire is realized by projecting a linear grating onto a photographic print of the record of the deformed grating, using a photographic enlarger. By this new method, a technique for describing a 3-D object by means of the slope of facets composing the object is made possible.