Microbending fiber-optic sensor design optimization

Periodic microbending along the axis of an optical fiber causes mode coupling which couples light from core modes to other core modes or to cladding modes. By monitoring the light power of core1 or cladding2 modes an applied field (pressure, displacement, acceleration) can be detected. Design considerations for optimum performance of such an intensity modulated microbending acoustooptic fiber sensor are discussed, and the relevant design parameters are given. The equivalent acoustic circuit of the sensor is determined, and its acoustic frequency response is predicted. From this analysis, designs for optimum sensor performance can then be made.