POLARIZATION PHASE-SHIFTING TECHNIQUE APPLIED TO A SPECKLE CORRELATION INTERFEROMETER USING AN IMAGE FIBER

A digital speckle correlation interferometer using an image fiber with a polarization phase-shifting technique is studied theoretically and experimentally. The correlation fringes obtained with this interferometer provide the data for determining the out-of-plane displacement of rough objects. In this interferometer, an image fiber is used for transmitting the speckle pattern arising from the object surface to a video processing system. The speckle patterns with high spatial frequencies can be optically sampled by using the image fiber without the aliasing effect which causes the distortion of the measured phase distribution.