Abstract
A close-range objective white light speckle method has been used for strain determination on simply curved surfaces. The speckle field is not the artificially printed random dots but only the radiance distribution of object surface which was slightly treated before the test to produce fine structure of optical details. The holographic film, instead of holographic plate, is attatched to the curved surface when illuminated by a flash light. Whole field fringe patterns are obtained with high sensitivities and large adjustable range. There is no longer a requirement to derive the speckle movement on the image plane from the object surface. Defocusing problem has been avoided. It can be practically applied to engineering problems with considerable convenience because of the very simple recording system and little demand for environmental stability.
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References
Wu Xiaoping, He shiping and Li Zhichao, Movement of space speckle, Fourth SESA International Conference on Experimental Mechanics, Boston, Mass. (May, 1980).
Zhou Xingeng Deformation measurement of curved surface by laser subjective speckle, Proceeding of the International Conference on Experimental Mechanics, Beijing, China. (Oct., 1985).
Chiang, F.P., Liu, P.S. and Lin, S. T., Multiaperture white light speckle method applied to the strain analysis of cylinders with holes under compression,Acta Solida Mechanica Sinica, 1, (1981), (in Chinese).
Chiang, F.P. and Kin, C.C., Strain determination on curved surfaces using far-field objective laser speckles,Opt. Eng.,21, 3 (1982), 441.
Kin, C.C. and Chiang, F.P., Objective laser speckle method for three dimentional displacement measurement on curved surfaces,Opt. Eng.,22, 1 (1983), 153.
JACK D.Gaskill, Linear System, Fourier Transforms and Optics, John Wiley & Sons, Inc. 1978.
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Meirong, T., Minhua, L. & Jinhu, H. Strain determination on curved surfaces by objective white light speckles. Acta Mech Sinica 3, 363–369 (1987). https://doi.org/10.1007/BF02486822
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DOI: https://doi.org/10.1007/BF02486822