基于保偏光纤纤芯错位熔接的液位传感器的研究

发布时间：2018-05-02 20:34

  本文选题：保偏光纤 + 光纤传感　； 参考：《中国计量学院》2015年硕士论文

【摘要】：科技的不断发展,工业的自动化程度也在不断提高,液位信息采集在许多领域也变得尤为重要,光纤液位传感器由于其优良性能而倍受青睐。本文重点对基于保偏光纤纤芯错位熔接结构的液位传感器进行了相关研究以及实验,以期获得更高传感性能,本论文的工作总结主要归纳如下：1、简述液位传感器发展状况和光纤液位传感器研究现状。2、阐述光纤偏振特性及其模间干涉的基本原理。首先阐述了光纤模式理论,然后简述了偏振光和单模光纤双折射特性及保偏光纤,最后对Mach-Zehnder光纤干涉仪的模间干涉理论进行了概述。3、提出了一种基于保偏光纤错位熔接的液位传感器。利用单模光纤-保偏光纤-单模光纤组成三明治型结构,对错位偏移量的大小及纤芯错位方向(快轴、慢轴及快慢轴45。方向对准)进行了实验分析,制作了一种沿其快轴错位对准方式的干涉仪。通过干涉仪分束端的错位结构激发产生的包层模作为探测信号接收液位信息的变化,最后通过实验数据拟合后得到的其波长漂移和光强变化对应灵敏度分别为-0.4956nm/mm和0.2204dB/mm,温度分析得出其灵敏系数约是13pm/℃。4、对多边形光纤扰模进行了模拟分析。阐述了天文观测中多模光纤的应用及多模光纤的基本理论,通过对正四边形纤芯光纤和正八边形纤芯光纤的模式模拟,分析验证了其在扰模中的优良性能以及与扰模相关的光纤参数关系。
[Abstract]:With the development of science and technology, the degree of automation of industry is also increasing, and the level information collection is becoming more and more important in many fields. Fiber optic liquid level sensor is very popular because of its excellent performance. This paper focuses on the research and experiment of liquid level sensor based on polarization maintaining fiber core dislocation welding structure in order to obtain higher sensing performance. The main work of this thesis is summarized as follows: 1. The development of liquid level sensor and the research status of optical fiber liquid level sensor are briefly described. The polarization characteristics of optical fiber and the basic principle of intermode interference are expounded. Firstly, the theory of optical fiber mode is introduced, and then the birefringence characteristics of polarized light and single-mode fiber and polarization maintaining fiber are briefly described. Finally, the intermodal interference theory of Mach-Zehnder fiber interferometer is summarized, and a liquid level sensor based on polarization maintaining fiber dislocation welding is proposed. The sandwich structure is made up of single mode fiber, polarization maintaining fiber and single mode fiber. The size of the offset and the direction of the core dislocation (fast axis, slow axis and fast and slow axis 45) are analyzed. An interferometer with misalignment along its fast axis is made. The cladding mode generated by the misalignment structure at the beam splitting end of the interferometer is used as the detection signal to receive the change of liquid level information. Finally, the corresponding sensitivities of wavelength drift and light intensity are -0.4956nm / mm and 0.2204dB / mm. the sensitivity coefficient is about 13pm/ 鈩，

本文编号：1835385