基于新型氧化物掺杂光纤的马赫-曾德尔干涉仪多参数测量传感器

A novel Mach-Zehnder interferometer sensor for multi-parameter measurement based on oxide-doped fiber

摘要:

针对固体火箭发动机结构健康监测,本文提出并制备了一种新型马赫-曾德尔干涉型传感器,传感结构由多模光纤(multimode fiber,MMF) 、氧化物掺杂光纤与多模光纤依次手动熔接而成。其中,掺杂光纤为传感单元,它的纤芯主要由Y₂O₃、Al₂O₃和P₂O₅掺杂构成,纤芯折射率(refractive index,RI) 呈现类线性分布。建立了传感器理论模型,分析了传感器的光场传输特性。研制了传感器样品,开展了温度、弯曲和应变实验。实验结果表明,传感器温度、弯曲、应变灵敏度分别为57 pm/℃、9.41 nm/m-1、3 pm/με,相比较同类型的传感器,灵敏度具有较大提高,同时表现出了不同的特征光谱特性。该传感器制备工艺简单,结构紧凑,可应用于固体火箭发动机内部温度、弯曲、应变多个参数的测量。

Abstract:

This paper proposes and prepares a new Mach-Zender interferometric sensor for structural health monitoring of solid rocket motors.The sensing structure is composed of a multimode fiber,an oxide-doped fiber and a multimode fiber (MMF),which are fused by hand in turn.Wherein the doped fiber is a sensing unit,the fiber core of the doped fiber is mainly formed by doping Y₂O₃,Al₂O₃ and P₂O₅,and the refractive index (RI) of the fiber core presents linear-like distribution.The theoretical model of the sensor is established,and the optical field transmission characteristics of the sensor are analyzed.The sensor samples are developed.Temperature,bending and strain experiments are carried out.The results show that the temperature,bending and strain sensitivities of the sensor are 57 pm/℃,9.41 nm/m-1 and 3 pm/με,respectively.Compared with the same type of sensor,the sensitivity is greatly improved,and the sensor shows different spectral characteristics.The sensor has the advantages of simple preparation process and compact structure,and can be applied to the measurement of multiple parameters such as temperature,bending and strain.