Abstract
Abstract
Digital fringe multiplication of three-dimensional photoelastic images using the image-division technique and multiple-angle relations of the cosine function is described and demonstrated. Fringe multiplication of two slices from a stress-freezing model to a factor of 9 is shown. The fractional fringe orders counted by this method agree well with that determined by the Tardy method and a null-balance compensator. The multiplication process is very simple and effective for practical use.
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