高灵敏度、高分辨率分布式光纤应力传感器研究

描述了分布式光光纤应力传感系统的近期发展及其应用。介绍一种分布式光纤应力传感器系统,该系统基于保偏光纤受外力扰动时模式耦合系数与外力大小有关的原理,采用偏振耦合干涉定位确定受力大小与空间位置方法,分析了系统的定位原理与测力大小原理以及光源、偏振器件等对系统灵敏度与分辨率的影响。系统采用SLD作光源,质子交换LiNbO3波导作偏振器件,在1.3 μm波长条件下,获得的应为灵敏度优于5%,空间分辨率小于10cm。

Research on Distributed Optical Fiber Stress Sensor with High Stress Sensitivity and High Spacial Resolving Power

Recent development and applications of distributed optical fiber stress sensor are described briefly. Based on the theory that coupling coefficient is related to external force, a distributed optical fiber stress sensor is introduced. Distribution of external force is measured by polarization coupling coherence. The principle of location and measuring strength of stress is discussed. The influence of light and polarizer and other things upon the sensitivity and resolving power of the sensor, is discussed. SLD is used as light and proton-exchange LiNbO3 wave-guide is used as polarizer. At the wavelength of 1.3 μm, the resolution of the sensor is better by ±10 cm and its sensitivity is better by 5%.