There is a class of material testing problems that lend itself to a non-contacting way of obtaining the measurand. Especially for specimens, that are small to very small in one or two dimensions (e. g. thin foils or small diameter fibres), or are heated to high temperatures a non-contacting way of testing is imperative. In this paper we report on the theory and applicability of a laser speckle shift displacement gradient measurement system as well as practical results obtained with the discussed system. Some of the results presented can not be obtained with other than optical means, because of the fragility or the physical dimensions of the specimen.
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