Novel phase unwrapping algorithm of DSPI for complex and discontinuous structure

A novel phase unwrapping algorithm of DSPI for complex structure is proposed in this paper. An image of the object to be measured with very high contrast can be obtained by the subtraction of two speckle pattern interferograms, whose optical phases are opposite. The complete image area of object to be measured can be correctly obtained from this high contrast image. By controlling the phase unwrapping procedure to be inside the image area of the object, the wrapped phase map of complex structure can be unwrapped. This novel phase unwrapping algorithm makes DSPI be able to be used to measure the complex structure in practical engineering, and will enlarge the application field of DSPI.