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Digital shearography is widely accepted in non-destructive inspection of honeycomb sandwich structures due to its
advantages of validity, non-contact, simple setup and robustness. In digital shearography, Michelson shear interferometer
(MSI) is a dominant shearing device because it is easy to change the shearing amount and direction. However, the
conventional digital shearography based on MSI suffers from the small angle of view which limits its employments in
full field inspection of a big size sample at a short working distance. A novel structure digital shearography with wide
angle of view introduced in this paper is developed to overcome the disadvantage. In the new shearography optical
arrangement, the image lens is separated with the camera and locates at the front of system. A 4f imaging system is used
to transmit the image of object from the imaging lens to the camera. The shearing device, MSI, locates between the
imaging lens and camera. The angle of view in this shearography has no limit to the setup but it is based on several
parameters, such as the focus length of the imaging lens and the size of the imaging device inside the camera. Thus wide
angle of view can be easily achieved by changing those parameters. Using this novel digital shearography, full field
inspection of the big size honeycomb sandwich structure can be rapidly conducted at a short working distance.
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