基于布里渊动态光栅的高灵敏度静压力传感器设计

设计了一种新型边孔型保偏光子晶体光纤,在包层中对称地引入两个大空气孔,纤芯区域与大空气孔之间仅有一层小空气孔。由平面应变假设将该模型进行二维简化,利用有限元法对该光纤的二维模型进行数值分析,通过计算不同温度和静压力下的双折射频移以研究其温度和静压力传感特性。研究表明,在较大静压力和温度范围内,该保偏光子晶体光纤无需掺杂任何应力材料就可以实现?2.1353 GHz/MPa的静压力灵敏度且具有温度不敏感性,其温度灵敏度仅为+0.1542 MHz/℃。另外,还对该光子晶体光纤的光学特性进行了分析,其满足单模传输条件、具有较小的限制性损耗和较大的有效模场面积。由于具有体积小、与其他光纤兼容度强、静压力灵敏度高、温度不敏感的特性,其在温度变化不定、静压力改变区间较大的环境中静压力精确测量的优势比较明显,较好的光学特性使其在油井、土木的监测应用等方面有着重要参考价值。

Design of High-sensitivity Hydrostatic Pressure Sensor Based on Brillouin Dynamic Grating

A new kind of polarization maintaining photonic crystal fiber with two side-holes is designed.There is only a layer of small air holes between the core and the large air hole,and two large air holes are introduced in the cladding symmetrically.The two-dimensional model was simplified by the plane strain hypothesis,the two-dimensional model of this fiber was numerically analyzed by the finite element method,and the characteristics of temperature and hydrostatic pressure sensing were studied by calculating the birefringence-induced frequency shift at different temperatures and hydrostatic pressures.As the studies show,within a large range of hydrostatic pressure and temperature,this polarization maintaining photonic crystal fiber can realize the hydrostatic pressure sensitivity of?2.1353 GHz/MPa and it is insensitive to temperature without doping any stress material.Its temperature sensitivity is only+0.1542 MHz/℃.In addition,the optical properties of the photonic crystal fiber were also analyzed.The proposed photonic crystal fiber satisfies the condition of single-mode transmission,has a small confinement loss and a large effective mode area.Due to its characteristics of small size,strong compatibility with other optical fibers,high hydrostatic pressure sensitivity and temperature insensitivity,it has obvious advantages in the accurate measurement of hydrostatic pressure in the environment with variable temperature and great hydrostatic pressure variation.Better optical properties make it has important reference value in monitoring application of oil well and civil engineering.