Fiber-optic rotation angle sensor based on fused fiber coupler

Abstract

We have proposed and demonstrated a rotation angle sensor based on the stress -optic effect of a fused fiber coupler whose transmission spectrum is altered by the torsional stress. The peak of transmission spectrum was shifted to longer wavelength region with rotation of the coupler. The rotation angle sensor revealed reproducibility and symmetric behavior with respect to the rotation direction. The sensitivity of the sensor was 0.367 [nm/degee].