Electronic speckle pattern shearing interferometer using a holographic grating

In this paper we propose a new method of shearing in an electronic speckle pattern shearing interferometry using holographic gratings. The system we are proposing consists of two parts: 1) to image the object onto an intermediate ground glass, and 2) the image on the ground glass is in turn imaged onto the photosensor of a CCD camera. A holographic grating placed in front of the ground glass screen is used for shearing the two images and for introducing phase stepping.