少模光纤长周期光栅——从模式转换到高灵敏度光纤传感

doi:10.3969/j.issn.0255-8297.2020.02.007

摘要/Abstract

摘要： 少模光纤长周期光栅具有波长选择性好、插入损耗低、结构灵活多变、集成度高、与光纤系统兼容等优点，是实现少模光纤中模式转换、涡旋模式调控的有效手段，在光纤通信和光纤传感领域都展现了巨大的应用价值.该文介绍了少模光纤长周期光栅在模式转换和光纤传感方面的研究进展，首先介绍了少模光纤长周期光栅的制备技术、模式耦合原理，重点介绍了少模光纤长周期光栅模式转换器，包括标准长周期光栅和螺旋长周期光栅，最后详述了基于少模光纤长周期光栅的光纤传感器的工作原理和实现方法.

关键词: 少模光纤, 长周期光栅, 模式转换, 光纤传感

Abstract: Few-mode fber (FMF) long-period grating (LPG) with advantages of good wavelength selectivity, low insertion loss, flexible structure, high integration and compatibility with optical fber systems,is an effective means to realize mode conversion and vortex mode regulation in the FMF, which have great potential for applications in the optical fber communications and fber-optic sensing. This paper presents the research progress of FMF-LPG in mode conversion and optical fber sensing. Firstly, the mode coupling principle and fabrication methods of FMF-LPG are introduced. Then, the mode converters based on FMF-LPG including standard LPG and helical LPG are investigated. Finally, the working principle and implementation method of fber-optic sensors based on FMF-LPG are demonstrated.

Key words: few-mode fber, long-period grating, mode converter, fber-optic sensing

中图分类号:

P751.1

赵云鹤, 刘云启. 少模光纤长周期光栅——从模式转换到高灵敏度光纤传感[J]. 应用科学学报, 2020, 38(2): 310-338.

ZHAO Yunhe, LIU Yunqi. Few-Mode Fiber Long-Period Gratings—From Mode Conversion to High Sensitivity Fiber-Optic Sensing[J]. Journal of Applied Sciences, 2020, 38(2): 310-338.

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