Study on the Monotonicity of Bending Loss of Polymer Optical Fiber

Abstract

Bending loss of polymer optical fibers (POFs) shows unexpected oscillatory behaviors due to the interference between whispering gallery mode and core mode for the cases of small bending radius and large bending angle. We have found a novel method of suppressing the oscillatory behavior of bending loss of POFs. By partially removing the cladding and core, the bending loss monotonicity with improved linearity was obtained for POFs with small bending radius in a large range of bending angles for the first time. This method is useful in the application of extreme large strain (e.g., ≥60%) sensors of POF.