曲面光纤光栅的理论和传感应用研究

In this project, the structure of grating grid is developed from plane to curved surfaces, the curved surface fiber grating (CSFG) with isolated grids is proposed, and the relative theory and sensing application are researched. It can both exploit the innovation space for designing and fabricating novel fiber grating, and provide the abundant realizing approach for developing and optimizing the optical field regulated function of fiber grating. This project will systematically launch the application fundamental research on CSFG in the respects of building model theory, simulating spectral characteristics, mechanism exploration and characterization, mode regulation and analysis, grating technology development, device design and the process, and experimental measures and analysis. The research focus is the CSFG with the grid of arc, elliptical and parabolic shapes, and the effectuation of new sensing characters and functions of the relative novel fiber device is designed and formed based on the CSFG. This project is also a research with innovate significance in multiaspect including theory, experiment, technology and application. The novel ideas, methods, structures and techniques have both scientific significance and application values for developing the minitype, ultrasensitivite and integrated fiber devices featured with excellent performance for vector sensing and environment monitoring ability, and promoting the development of fiber grating theory, fiber grating sensing technology and the material network.

本项目将栅格结构由平面发展为曲面，提出并研制具有分立栅格结构的曲面光纤光栅，开展相关的理论和传感应用研究，不仅为设计和研制新型光纤光栅开拓了创新空间，也为提升和优化光纤光栅调控光场功能提供了丰富的实现途径。本项目将在模型理论建立、光谱特性模拟、机理探索表征、模式调控分析、成栅技术开发、器件设计研制、实验测量分析等方面，系统地开展对曲面光纤光栅的应用基础研究，重点研究栅格结构为圆弧型、椭圆型、抛物型的曲面光纤光栅，以及由此设计并研制的新型光纤器件的传感新特性和新功能实现。本项目是一个在理论、实验、技术及应用多方面具有创新意义的研究课题，其中的新思想、新方法、新结构及新技术，对于研制具有矢量传感及环境监测等功能的微型、超敏、集成的高性能光纤器件，以及由此对光纤光栅理论、光纤光栅传感技术的发展和物联网的推动，均具有非常重要的科学意义和应用价值。

本项目基于调控栅格形状对光纤光栅特征的影响，系统开展由曲面栅格构建的光纤光栅在结构特征、制备工艺、光谱特性、传感性能等方面的应用基础研究。在理论方面，根据光纤曲面折射率调制区域对传输光波的特殊调制效果，探索曲面栅格形状与光栅性能的关系；利用模拟软件建立曲面栅格及曲面光纤光栅模型，分析栅格区域的折射率分布特征；利用有限元法模拟计算曲面光纤光栅的透射光谱，研究曲面栅格的曲率半径、弯曲方向及分布对光谱特征的影响。在实验方面，搭建曲面光栅制备与传感检测平台，优化曲面栅格的激光曝光写制技术，测试曲面光纤光栅对不同参量的响应特性；设计并研制出多种曲面光纤光栅，实现了对弯曲、扭转、应变、折射率等参量的方向性、高灵敏度感测效果。本项目设计并制备了一系列由不同形状、不同半径分布的曲面栅格构成的曲面光纤光栅器件，获得了明显强于传统平面光纤光栅的折射率调制效果，实现了对传输光场的有效调控和多参量的高灵敏度测量效果，相关研究工作及创新成果对设计和研制新型光纤光栅以及发展新一代光纤传感技术具有重要的理论意义和应用价值。