强度调制型光纤折射率传感器的设计与研究

Design and Study of Fiber Refractive Index Sensor Based on Intensity Modulation

研制了一种基于菲涅耳反射原理的测量液体折射率的光纤传感器.该传感器采用普通FC/PC尾纤插头作为传感头.整个实验系统需要的元件少、光路简单.讨论了测量的基本原理和数据处理方法.采用相对强度的数据处理方法,有效地消除了光源不稳定性和光路中各种损耗所带来的误差,提高了系统的测量准确度.实验结果表明,测量准确度能够达到10-4量级,并且适合微量液体的测量.该测量方法还可扩展到固体、气体和其它与折射率相关参量的测量.

A refractive index fiber sensor system of liquid based on Fresnel refractivity is developed. The common FC/PC fiber end is used to be detector tip. The light circuit is simple and the system is easy to operate. The basic principle and data procession method are discussed. Using the relative intensity method, the influence brought by the stability of light source and insertion losses are eliminated effectively. The theory analysis and experiment results prove the possibility of this method. The analysis of measured data demonstrates that the measurement precision can achieve 2 × 10^-4. The system also can be used to measure the refractive index of solid, gas and other parameters which are involved with refractive index.