液氮温度光纤Bragg光栅的应变传感特性  

Strain Response of FBG at Liquid Nitrogen Temperature

作　　者：黄国君[1] 邵进益[1] 王秋良[2] 邓凡平[2] 戴锋[1] 冯遵安[2] 

机构地区：[1]中国科学院力学研究所,北京100080 [2]中国科学院电工研究所,北京100080

出　　处：《光电子．激光》2007年第7期773-775,共3页Journal of Optoelectronics·Laser

基　　金：国家自然科学基金资助项目(10532070;50577063);中国科学院知识创新重要方向性资助项目(KJCX2-SW-L03-01)

摘　　要：对光纤Bragg光栅(FBG)液氮(77K)下的应变传感技术及应变特性进行了研究。实验和分析表明:常温下FBG反射谱中的单个中心峰在低温下会劈裂为多峰,它产生于光纤、粘贴胶和金属基底热膨胀系数间的差异引起的强烈非均匀热弹性应变,使常温下均匀的光栅变啁啾化。建立了多种技术手段,成功消除了低温多峰现象,并测得了FBG低温和常温下的应变传感特性。实验结果表明:FBG的应变灵敏系数与温度无关。The strain sensing properties based on fiber Bragg gratings（FBGs） at the liquid nitrogen temperature （77 K） were investigated. It was found that the single central peak in the reflection spectrum of FBGs at the ambient temperature is split into multiple peaks at the cryogenic temperature. This abnormality is attributed to the severely inhomogeneous thermo-elastic strain over the greeting of FBGs due to the mismatch of the coefficients of thermal expansion between the glass fiber core,epoxy adhesive and metal substrate,which transforms the original uniform grating into a chirped one. Some technologies were developed to eliminate the multi-peak phenomenon and, eventually, the strain responses of FBGs at the ambient and liquid nitrogen temperatures were measured. The experimental results show that the strain sensibility of FBGs is independent of temperature,which demonstrates that FBGs are excellent cryogenic strain sensors.

关 键 词：光纤Bragg光栅(FBG) 应变传感器 液氮 

分 类 号：TN253[电子电信—物理电子学]