论文标题
分布式覆层模式光纤传感器
Distributed cladding mode fiber-optic sensor
论文作者
论文摘要
几十年来，对覆层以外的物质的分析一直挑战了光纤传感器社区。一种常见的解决方案依赖于覆层模式中的光的传播。但是，从这些模式到/来自这些模式的光耦合通常基于特定位置的永久光栅，这将传感器仅限制点测量。在这项工作中，我们在任意位置的短部分中介绍了标准纤维的核心和覆层模式之间光的动态，随机访问耦合。耦合是基于通过两个编码的泵波和第三个光学探针波的模式散射刺激布里鲁因动态光栅的。所有波浪均以核心模式启动和收集。没有永久的光栅刻有。用2 m范围和8厘米的分辨率证明了周围介质的分布式感应。测量区分纤维以外的水和乙醇。覆层以外的本地指数的测量精确度为0.004-0.0004折射率单位。
The analysis of substances outside the cladding has challenged the optical fiber sensors community for decades. A common solution relies on the propagation of light in cladding modes. However, the coupling of light to/from these modes is typically based on permanent gratings in specific locations, which restrict the sensors to point measurements only. In this work, we present dynamic, random-access coupling of light between core and cladding modes of standard fibers, in arbitrarily located short sections. Coupling is based on the stimulation of Brillouin dynamic gratings by two coded pump waves and intermodal scattering of a third optical probe wave. All waves are launched and collected inthe core mode. No permanent gratings are inscribed. Distributed sensing of surrounding media is demonstrated with 2 m range and 8 cm resolution. Measurements distinguish between water and ethanol outside the fiber. The measurement accuracty of the local index outside the cladding is 0.004 - 0.0004 refractive index units.
