Abstract
This paper describes a method of increasing the sensitivity of interferometric surface-strain measurement. The new technique utilizes the fact that the interference pattern has a region in which the fringe motion is linearly related to the fringe intensity. The theory of this linear gage, a description of measurement techniques, and the results of evaluative experiments are presented.
Results show that the optical gage has the following characteristics: a gage length of 0.005 in. (0.125 mm), a sensitivity of 2 microstrain, a range of ±200 microstrain for 1-percent deviation from linearity, and an accuracy of 1 percent when compared with a foil gage.
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References
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Sharpe, W.N. A short-gage-length optical gage for small strain. Experimental Mechanics 14, 373–377 (1974). https://doi.org/10.1007/BF02323564
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DOI: https://doi.org/10.1007/BF02323564