Electronic Laser Speckle Interferometer for Displacement Measurement using Digital Image Processing Technique

Digital speckle image correlation techniques have been successfully proven to be an accurate displacement analysis tool for a wide range of applications. In this paper, a new Electronic Laser Speckle Pattern Interferometer based on Michelson interferometer is designed. An object beam back scattered of an object surface and a reference beam, originating from the same laser light source are superimposed on a charge couple device and form the interference fringe pattern (speckle gram). Subtraction of speckle pattern before and after deformation of aluminum plate gives the measurement of displacement by using fringe analysis with a suitable image processing algorithm. 