Spatially weighted vibration sensors using tapered two-mode optical fibers

Spatially weighted optical fiber sensors that filter specific vibration modes from one-dimensional beams placed in clamped-free and clamped-clamped configurations are presented. The sensitivity of the sensors is varied along the length of the fiber by tapering two-mode, circular-core fibers. Selective vibration mode suppression on the order of 10 dB has been obtained using weighted sensors. Experimental results are described, and applications for distributed sensors are proposed. >

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