Automated analysis in digital speckle shearing interferometry using an object step-loading method

Department of Mechanical & Production Engineering, National University of Singapore, 10, Kent Ridge Crescent, Singapore 0511, Singapore
Optics Communications (Impact Factor: 1.45). 06/1994; 108(4-6):214-218. DOI: 10.1016/0030-4018(94)90651-3


Automated analysis in digital speckle shearing interferometry using the conventional two-frame differencing method is hindered by phase unwrapping errors and unresolved fringe patterns due to excessive object load. An object step-loading method with the ability to surmount these limitations is proposed and demonstrated. An added advantage of the proposed method is its ability to yield the entire slope versus load history within one loading cycle.

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