Temperature-insensitive fiber cantilever vibration sensor based on a fiber-to-fiber structure

A simple optical fiber cantilever vibration sensor consisting of two opposite aligned bare optical fibers sealed in a quartz capillary is presented.The fiber with the longer bare section is suspended in air and acts as a cantilever.By detecting the transmission power of the sensor directly,the environmental vibrational frequencies and amplitudes may be obtained.By adjusting the cantilever’s natural deflection angle,the sensor can achieve high sensitivity,good response linearity,and a wide dynamic range.Coupling conditions are optimized to minimize temperature effects by simply setting an appropriate air gap between the bare fibers.