摘要
环境折射率和环境温度变化是影响光纤应变测量误差的主要因素。本文利用双模光纤纤芯双模式(LP01和LP11)支持特性设计了一款环境折射率不敏感的双模光纤(DMF)长周期光纤光栅(LPFG)应变传感器。设计了传感器模型结构,制作了最优化参数的传感器样品。实验测试了DMF-LPFG传感结构对外部环境中应变、温度和折射率的响应。通过在单模光纤上用紫外激光刻写的布拉格光栅(FBG)解决了环境温度的交叉影响。轴向应变实验结果表明,该新型结构传感器在0με~840με应变范围内其轴向应变灵敏度可以达到-5.4 pm/με,该灵敏度值相比较于普通LPFG有很大提高。温度在25℃~80℃范围内其灵敏度为58.86 pm/℃,表现出较好的线性度。同时,传感器对环境折射率变化表现出不敏感特性。通过采用双参数矩阵对少模LPFG和FBG的应变和温度灵敏度进行处理,可以实现双参数的同时解调。该新型复合光栅结构具有良好的传感性能和工程应用前景。
The variation of ambient refractive index and ambient temperature is the main factor affecting the error of optical fiber strain measurement.In this paper,a strain sensor based on the dual-mode fiber(DMF)long period fiber grating(LPFG)is designed.The sensor model structure was designed,and the sensor samples with optimized parameters were produced.The experiment tested the response of the DMF-LPFG sensing structure to the strain,temperature and refractive index in the external environment.Through the Bragg grating(fiber Bragg grating,FBG)written on the single-mode fiber with a UV laser,the cross effect of the ambient temperature is solved.The results of the axial strain experiment show that the axial strain sensitivity of the new structure sensor can reach-5.4 pm/μεin the strain range of 0με~840με,which is greatly improved compared to the ordinary LPFG.The sensitivity is 58.86 pm/℃in the temperature range of 25℃~80℃,showing good linearity.At the same time,the sensor is insensitive to changes in ambient refractive index.The dual-parameter matrix is used to process the strain and temperature sensitivity of the few-mode LPFG and FBG to achieve dual-parameter simultaneous demodulation.The new composite grating structure has good sensing performance and engineering application prospects.
作者
王向宇
乔学光
禹大宽
Wang Xiangyu;Qiao Xueguang;Yu Dakuan(Northwestern Polytechnical University,the School of Science,Shaanxi Key Laboratory of Optical Information Technology,Xi’an,Shaanxi 710072,China;Northwest University,Department of Physics,Xi’an,Shaanxi 710069,China)
出处
《光电工程》
CAS
CSCD
北大核心
2021年第3期76-82,共7页
Opto-Electronic Engineering
基金
国家科技攻关资助项目(61327012)
国家自然科学基金资助项目(61735014)
国家重大科研仪器研制资助项目(61927812)
国家重点研究发展计划(2017YFB0405502)。
