Abstract: A method and apparatus for moire ray deflection mapping for determining properties of an object in which a point source of light producing a diverging beam of direct light is passed through a first optical system including the object to be examined, which system retraces the light in the form of a converging beam of reflected light from the examined object back towards the point source. The converging beam of reflected light is intercepted before reaching the point source and is passed through a second optical system which collimates the beam of reflected light. The collimated beam is then directed through first and second gratings at a preselected angular orientation with respect to each other to produce moire fringe patterns providing an indication of the properties of the examined object. An important advantage in the above novel method is that the same setup can be used for measurements of both phase objects and specular surfaces.

Abstract: A system and method for determining modulation transfer function (MTF) of an optical element or system employs a moire deflectometer. A selected central portion of monochromatic light is directed to the first grating of the moire deflectometer through or from the optical system, resulting in a moire pattern in which the contrast along an axis incident to the moire fringes is indicative of the MTF of the optical system for a particular spatial frequency, which is dependent on the spacing between the gratings of the moire deflectometer.