User:Odedkafri

An interferometry technique entitled moiré deflectometry [1], in which the object to be tested (either phase object or secular surface) is mounted in the course of a collimated beam followed by a pair of transmission gratings placed at a distance from each other. The resulting fringe pattern, i.e., the moiré deflectogram, is a map of ray deflections corresponding to the optical properties of the inspected object. Hence Moiré Deflectometry is a powerful tool for nondestructive optical testing. A major advantage of Moiré deflectometry is that it less sensitive to mechanical vibration and therefore it is widely used in ophthalmic industry flam analysis and wind tunnel measurements as a quantitative replacement to Schlieren photography and Shadowgraphy. [1] O. Kafri Optics letters 5,555 (1980)