光纤端面涂覆敏感材料的高灵敏度传感器

Optical fiber end-face coated with sensitive-material for high sensitivity sensor

描述了一种基于法布里-佩罗干涉仪(Fabry-Perot interferometer, FPI)结构的双参数光纤传感器,并演示了它可以同时测量气压和温度。所提出的FPI传感结构由覆盖在单模光纤端面上半球形的紫外固化胶组成,FPI产生的光谱干涉峰对环境温度和气压变化敏感。选择传感器干涉谱中两个谐振峰波谷Dip 1和Dip 2,跟踪它们的波长随气压和温度的变化,构建传输矩阵,能够同时测量气压和温度,并消除交叉敏感。实验结果表明Dip 1点的气压与温度灵敏度分别为2.925 nm/MPa和-1.165 nm/℃,Dip 2点的气压与温度灵敏度分别为4.715 nm/MPa和-1.209 nm/℃。利用Dip 1和Dip2的气压与温度灵敏度构建测量矩阵,传感器实现了多参数测量。通过长时间稳定性实验发现传感器测量气压与温度的最大误差分别为0.068 MPa和0.19℃。该传感器具有灵敏度高、结构简单紧凑、造价低廉等优点,在工业生产中具有一定的应用价值。

A dual-parameter fiber-optic sensor based on Fabry-Perot interferometer(FPI) structure is described and demonstrated to measure gas pressure and temperature simultaneously.The proposed sensing structure consists of an extrinsic FPI in the form of hemispherical ultraviolet curing glue capped on a single mode fiber end face.The spectral interference peak produced by FPI is sensitive to ambient temperature and gas pressure variations.We select two resonant peak dips in the interference spectrum to track their wavelength changes with gas pressure or temperature, constructing transport matrices capable of measuring both gas pressure and temperature and eliminating mutual cross-sensitivities.The experimental results showed that the gas pressure and temperature sensitivity at dip 1 were of 2.925 nm/MPa and-1.165 nm/℃,and the gas pressure and temperature sensitivity at dip 2 were of 4.715 nm/MPa and-1.209 nm/℃,respectively.Building the measurement matrix using the gas pressure and temperature sensitivity of dip 1 and dip 2,the sensor can realize the multi-parameters measurement.The stability experiment of the sensor showed that the measurement error of the gas pressure and temperature were of 0.068 MPa and 0.19 ℃,respectively.The sensor has high sensitivity, low cost, simple and compact structure.It has certain application value in industrial production.