Miniature on-fiber extrinsic Fabry-Perot interferometric vibration sensors based on micro-cantilever beam

An on-fiber extrinsic Fabry-Perot interferometric (EFPI) vibration sensor based on micro-cantilever beam is proposed and experimentally demonstrated. The micro-cantilever beam, with a cantilever length of 80μm and a cantilever thickness of 5μm, is created perpendicular to the fiber axis by using the femtosecond laser micro-machining technique. The on-fiber vibration sensor has same diameter with that of the single mode fiber. An acceleration sensitivity of 11.1 mV/g@300 Hz in the range of 0.5-5g is demonstrated experimentally. This on-fiber and micro-cantilever beam design allows for the sensor to be smaller size and higher temperature resistance.