基于端面镀膜的Fabry-Perot光纤传感器研究

应用模式耦合理论计算了外腔式Fabry-Perot（F-P）干涉型光纤传感器的输出光强与F-P
腔长的关系。对组成F-P 腔的光纤端面进行了磨平抛光及镀多层电介质膜处理，使光纤端面反射率为70%，从而提高了传感器的抗干扰能力,简化了探测系统。将该传感器与电阻应变片作对比测量实验，其结果完全一致。
关键词：光纤传感器; 法布里-珀罗干涉；模式耦合理论; 电介质薄膜
Abstract: The relation between the output light intensity of extra-cavity type Fabry-Perot (F-P) interferometric optic fiber sensor and F-P cavity length is calculated with mode coupling theory. The end face of optic fiber that formed F-P cavity is ground, polished and coated with multi-layer dielectric film. In this way the reflectivity of the end face of optic fiber is as high as 70%, thus anti-interference capability of the sensor is improved and the detecting system is simplified. A comparison for the measuring experiments carried out by the sensor and resistance strain gauge, their results are entirely consistent.
Key words: Optical fiber sensor; Fabry-Perot interferometry; Mode coupling theory; Dielectric film