Abstract
A new technique has been developed to determine both the transmitted and the reflected stress-optical constants. The reflected optical constant is associated with the light reflected from the rear face of a transparent material. The stress-optical constant related to the light reflected from the front surface is not considered in this paper since it is equal to Poisson's ratio divided by Young's modulus. In this new method, a monochromatic light beam emitted from a He−Ne laser impinges on the area surrounding a circular hole under load in a plate. A digital image-analysis system, EYE-COM III, is used to determine the points of the highest light intensity of the caustic that results from the light transmitted or reflected from the rear face of the plate. The effect of the hole size in optically isotropic materials is investigated.
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Younis, N.T., Zachary, L.W. A new technique for the determination of stress-optical constants using the shadow spot method. Experimental Mechanics 29, 75–79 (1989). https://doi.org/10.1007/BF02327785
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DOI: https://doi.org/10.1007/BF02327785