A Digital Laser Speckle Technique for Generating Slope Contours of Bent Plate
A digital method is proposed whereby spatial speckles created when an optically rough surface is illuminated by a diffuse coherent laser beam are used to generate slope contour fringes. This is done by photographing the speckles contained in a parallel plane in front of the plate before and after deformation. The resulting photographs are then Fast Fourier Transformed twice with the digital image correlation software CASI to produce slope contours.
KeywordsLaser speckle Digital speckle photography Digital image correlation Stress analysis Plate bending
We gratefully acknowledge the support of Dr. Rajapakse, and the financial support of the Office of Naval Research through award NO.-N00014-17-1-2873.
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