Vibration sensing using a tapered bend-insensitive fiber based Mach-Zehnder interferometer

Optics Express (Impact Factor: 3.49). 02/2013; 21(3):3031-3042. DOI: 10.1364/OE.21.003031
Source: PubMed


In this study, a novel fiber-optic sensor consisting of a tapered bend-insensitive fiber based Mach-Zehnder interferometer is presented to realize damped and continuous vibration measurement. The double cladding structure and the central coating region of the in-fiber interferometer ensure an enhanced mechanical strength, reduced external disturbance, and a more uniform spectrum. A damped vibration frequency range of 29-60 Hz as well as continuous vibration disturbances ranging from 1 Hz up to 500 kHz are successfully demonstrated.

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    • "Another feature is the multitude of different strategies for designing and using fiber sensors [1] [2] [3]. One the most interesting structures is a tapered optical fiber; they have been studied for several decades to sense temperature [4], vibration [5], curvature [6], biochemical effects [7] [8] and refractive index [9] [10] [11]. Fiber sensors can be designed to determine tiny refractive index changes by a shift of the transmission curve. "
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