长周期光纤光栅的轴向应变传感特性研究  

Axial Strain Characteristics of Long Period Fiber Gratings

作　　者：张自嘉[1] 王昌明[1] 

机构地区：[1]南京理工大学机械学院仪器系,南京210094

出　　处：《传感技术学报》2007年第5期1003-1006,共4页Chinese Journal of Sensors and Actuators

基　　金：江苏省博士后基金资助

摘　　要：利用不同包层模的长周期光纤光栅(LPFGs)具有不同的轴向应变灵敏度,降低或提高应变灵敏度对通信和传感领域具有重要意义.利用分析各向异性波导的方法,从理论上分析了LPFGs对轴向应变的响应特性,并进行了实验研究.当光纤受到轴向应变时,纤芯和包层都变成了单轴晶体,利用相位匹配条件和单轴晶体光纤的本征方程,研究了LPFGs的谐振波长对轴向应变的响应特性.结果表明,基于不同包层模的LPFGs,对轴向应变的灵敏度有较大差别.谐振波长有向长波方向偏移,也有向短波方向偏移.模序较低时,灵敏度较小,中等模序灵敏度最大,高阶模序灵敏度则较高.Long period fiber gratings （LPFGs） coupling the core mode to different cladding modes possess different characteristics. It is significant to decrease or increase the axial strain sensitivities for using in communication or sensing. The characteristics of the long-period-fiber gratings （LPFGs） applied axial strain are investigated theoretically and experimentally by use of the anisotropic optical fibers. When applied uniform axial strain, the fibers＇ core and cladding all become the uniaxial crystal. The analytic expression of the strain sensitivity of LPFGs is derived. Analysis reveals that the strain sensitivity of LPFG based on different cladding mode is different greatly including the value and the varying direction of the wavelength shift. The sensitivity of LPFG based on lower or higher mode order is less than that of the middle-order mode.

关 键 词：导波光学 长周期光纤光栅(LPFG) 弹光系数 各向异性波导 本征方程 

分 类 号：TN25[电子电信—物理电子学] TN929.11