Three-wavelength electronic speckle pattern interferometry with the Fourier-transform method for simultaneous measurement of microstructure-scale deformations in three dimensions.

Eric B Flynn; Lori C Bassman; Timothy P Smith; Zamir Lalji; Laurel H Fullerton; Tommy C Leung; Scott R Greenfield; Aaron C Koskelo

doi:10.1364/ao.45.003218

PubMed · 16676025

Three-wavelength electronic speckle pattern interferometry with the Fourier-transform method for simultaneous measurement of microstructure-scale deformations in three dimensions.

Eric B Flynn·Lori C Bassman·Timothy P Smith·Zamir Lalji·Laurel H Fullerton·Tommy C Leung·Scott R Greenfield·Aaron C Koskelo

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Abstract

We present the simultaneous measurement of three-dimensional deformations by electronic speckle pattern interferometry using five object beams and three colors. Each color, corresponding to an orthogonal direction of displacement, is separated through dichroic filtering before being recorded by a separate CCD camera. Carrier fringes are introduced by tilting the beam path in one arm of each of the three interferometers. The measured deformation modulates these carrier fringes and is extracted using the Fourier-transform method to achieve high displacement sensitivity. The field of view is on the order of a millimeter, making the system suitable for study of microstructural deformations. We compare experimental results with calculated values to validate out-of-plane and in-plane deformation measurements and demonstrate sensitivity on the order of 10 nm.

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Algorithms Elasticity Fourier Analysis Image Enhancement Image Interpretation, Computer-Assisted Imaging, Three-Dimensional Interferometry Materials Testing Refractometry Reproducibility of Results Sensitivity and Specificity Stress, Mechanical Journal Article

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BibTeX RIS

Eric B Flynn, Lori C Bassman, Timothy P Smith, Zamir Lalji, Laurel H Fullerton, Tommy C Leung, Scott R Greenfield, Aaron C Koskelo. 2006-05-10. Three-wavelength electronic speckle pattern interferometry with the Fourier-transform method for simultaneous measurement of microstructure-scale deformations in three dimensions.. https://doi.org/10.1364/ao.45.003218

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