保偏光纤双折射度压力敏感性分析

Pressure Sensitivity Analysis of Polarization-maintaining Fiber Birefringence

基于有限元法对不同外界压力作用下的两种典型保偏光纤——熊猫保偏光纤(PAND Apolarization-maintaining fiber,PANDAPMF)和保偏光子晶体光纤(Polarization-Maintaining Photonic Crystal Fiber,PM-PCF)的内部应力场分布与光学特性关系进行分析,求解保偏光纤有效折射率(Effective Refractive Index,ERI)和双折射度对外界压力及其作用形式的响应规律。研究结果显示在单向受力条件下,两种保偏光纤的双折射度变化率均可达到10^-6RIU/MPa;在环向均匀受力条件下,PM-PCF的双折射度变化率为10^-6RIU/MPa,远高于PANDAPMF的10^-11RIU/MPa量级,具有更高的敏感特性。为干涉型保偏光纤传感器的设计和优化提供了理论依据和参考数据,具有较好的工程应用价值。

Based on the finite element method,the relationship between the internal stress field distribution and the optical characteristics of two typical polarization-maintaining fibers - PANDA polarization-maintaining fiber (PANDA PMF) and polarization-maintaining photonic crystal fiber (PM-PCF),is analyzed under different external pressures to solve the response law of the effective refractive index (ERI) of the polarization-maintaining fiber and the birefringence to the external pressure and its action form.Results show that under the condition of one-way stress,the birefringence change rate of both polarization-maintaining fibers can reach 10^-6 RIU/MPa;under biaxial uniform stress,the birefringence change rate of PM-PCF is 10^-6 RIU/MPa,which is much higher than that of PANDA PMF on the level of 10^-11 RIU/MPa,and has higher sensitivity.This research provides a theoretical basis and reference data for the design and optimization of interference-type polarization-maintaining fiber sensors and has good engineering application value.