基于马赫-曾德尔干涉的温度和应变同时测量的光纤传感器研究

Study of fiber sensor for the simultaneous measurement of temperature and strain based on Mach-Zehnder interferometer

提出了一种基于马赫-曾德尔干涉的温度和应变双参数同时测量的光纤传感器,其结构是在单模光纤(SMF)上分别熔接两个球形结构并在SMF光纤中间熔接一段细芯光纤(TCSMF)。利用光纤的纤芯模、包层模对温度、应变的灵敏度差异,通过检测不同级次的干涉谷的特征波长位移变化,结合敏感矩阵实现了对温度、应变双参数的同时测量。实验选取位于波长1 545.1nm和1 554.8nm处的干涉谷进行温度和应变的同时测量,测得两个波谷的温度灵敏度分别为53.86pm/℃和47.51pm/℃,两个波谷的应变灵敏度分别为0.75pm/με和1.39pm/με,并且不同级次干涉波谷的波长位移量与外界温度和应变具有良好的线性度。

A fiber sensor based on Mach-Zechnder interferometer（MZI）for simultaneous measurement of temperature and strain is proposed in this paper.The fiber sensor is constructed by sandwiching a thin core fiber between two spherical-shaped fibers.By observing the wavelength shifts of different interference dips and using the sensitivity matrix,temperature and strain can be measured simultaneously,since the core modes and the cladding modes have different sensitivities to these two external parameters.The wavelength dips at 1545.1nm and 1554.8nm are chosen.Experimental results indicate that the temperature sensitivities of the dips are 53.86pm/℃and 47.51pm/℃,and the strain sensitivities of the dips are 0.75pm/μεand 1.39pm/με,respectively.The linearity of the experiment results is good.