Since shearing interferometry, also called shearography, does not depict fringes caused by object tilt, it is a tool well suited for either nondestructive testing of objects under load or for quantitative evaluation of flexural strains. In traditional shearing interferometry, observation of fringes requires optical processing of double exposed interferograms. Hence the technique is not in real time. This paper explores the possibilities and limitations for real time shearing fringe observation using the electronic speckle pattern interferometry technique. Prospects for quantitative determination of local tilt and flexural strain using the the phase shifting technique are commented on, and some preliminary results are shown.
|Title of host publication||Selected Papers on Electronic Speckle Pattern Interferometry. Principles and practice.|
|Place of Publication||Bellingham, Washington, USA|
|Publisher||SPIE Optical Engineering Press|
|Publication status||Published - 1996|