基于渐逝波耦合的网络化光纤温度传感器研究

Research on the optical fiber temperature sensor network based on evanescent wave

基于光纤渐逝波耦合原理,在光纤耦合器的熔锥区涂敷温敏材料制得光纤温度传感器,并将3个传感头级联,构建温度传感器网络。采用锁相环技术测试了各传感器的分光可见度随温度的变化关系。实验表明,在-40^+90℃范围内,随着温度的增加各传感器的分光可见度单调增加,并通过零值点。利用三次多项式函数对温度传感特性曲线进行拟合,并对整个传感网络系统进行定标,多次测试结果表明,本系统的温度测量准确度优于±0.2℃。

Based on the coupling principle of fiber evanescent wave, a fiber temperature sensor network was constructed by cascading fiber couplers coated with temperature sensitivity material. The coupling visibilities（CV） of temperature sensor heads were measured with phase lock loop technique. The experimental results show that the CV increased monotonically and passed through the zero point at the temperature range from 40 ℃ to ＋ 90 ℃. The temperature sensing curves were fitted with 3rd order polynomial and the results show the temperature accuracy is higher than ,±0. 2 ℃.