Design and study of mechanical transducers for an optical-fiber accelerometer based on polarization effects

This paper presents different mechanical transducers designed to perform acceleration measurements with an optical fiber. The transducer subjected to a vibration deforms the fiber, inducing a birefringence variation that leads to the modulation of the light state of polarization. The different transducers are numerically and experimentally studied. In particular, the resonance frequencies and sensitivities are compared. For accelerations applied along the sensing axes, resonance frequencies from 1500 Hz to 3950 Hz are measured, with sensitivities that range from 4×10-4 rad/(m/s2) to 1×10-3 rad/(m/s2). However, lower-order vibration modes exist, that lead to high transverse sensitivities. A method to reduce these transverse sensitivities is presented.