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Shearography is a laser based optical method that is similar to holographic interferometry and ESPI. It is a full-field, non-contacting and non-destructive measurement method for the surface deformation. It overcomes some of the disadvantages of holography; it does not need a reference beam, so that it obtains vibration isolation and simplifies the setup. These advantages grant shearography the ability to be a practical measurement tool and it has already gotten many industrial acceptances for non-destructive testing The embedment of the phase shift technique improves dramatically the measuring sensitivity and accuracy of the shearography. It uses the piezoelectric as the carrier to generate a known phase gap and takes multiple images with the phase before and after the sample is loaded, so that the phase map is calculated. And for each pixel the phase is accurate. However, the disadvantage of the phase shift technique is the time consumption.