Fiber optic Fabry-Perot strain gauge

A local all-fiber Fabry-Perot interferometric strain sensor is reported. The device makes use of a simple semireflective fusion splice technique and is operated in reflection mode. Five sensors of gauge lengths of approximately 10 mm were fabricated and adhered to the surface of a cantilever beam. The phase-strain sensitivity, Delta phi / Delta L, was measured to be 2.24+or-0.07*10/sup 7/ m/sup -1/ ( lambda =632.8 nm) and found to be symmetric with respect to tension and compression.<
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