《In-line Fiber Microcantilever Vibration Sensor》.pdf

APPLIED PHYSICS LETTERS 103, 211113 (2013) In-line fiber microcantilever vibration sensor Ping Lu, Yanping Xu, Farhana Baset, Xiaoyi Bao,a) and Ravi Bhardwajb) Department of Physics, University of Ottawa, 150 Louis Pasteur Street, Ottawa, Ontario K1N 6N5, Canada (Received 4 October 2013; accepted 6 November 2013; published online 20 November 2013) We demonstrate a fiber-based vibration sensor that involves an enclosed suspended microcantilever integrated with a readout fiber, providing in-line measurement of frequency and amplitude of vibration. The microcantilever is fabricated from a bend-insensitive fiber by chemical etching and fused to a single-mode fiber. Vibration induced periodic bending of the microcantilever angularly scans the readout fiber core resulting in output power modulation corresponding to certain drive frequencies and voltages of a shaker. Experimental results agree well with the theoretical analysis and demonstrate a continuous vibration frequency range of C 5 Hz–10 kHz with a maximum signal-to-noise ratio of 68 dB. V 2013 AIP Publishing LLC. [/10.1063/1.4832342] Vibration sensors are indispensable for nondestructive BIFs with depressed-index structures have recently been inspection of civil infrastructures, structural health monitor- developed to allow light confinement at a smaller bending ra- ing, and environmental surveillance of seismic activity and dius with ultralow bending losses.20–22 An intensity-based volcanic eruptions. While piezoelectric accelerometers are