Real-time moiré interferometry
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A high-frequency moiré interferometric technique to continuously monitor in-plane surface displacement is presented. This technique employs fiber optics and a thermoplastic device to holographically record the initial carrier pattern produced on the surface of a test specimen. The carrier is modulated as the specimen deforms and moiré fringes, indicative of in-plane displacement, are observed in real time. Unwanted holointerferometric patterns are eliminated by appropriately adjusting the polarization of the reference wavefront. This paper describes a demonstration of the real-time technique as applied to the study of deformations in a notched beam subjected to three-point loading.
KeywordsMechanical Engineer Fluid Dynamics Fiber Optic Test Specimen Surface Displacement
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