基于F-P干涉仪溶液浓度微变量实时监测系统的研究

Real-time High Sensitivity Variation of Solution Concentration Monitor Based on Fabry-Perot Interferometer

设计了一款基于Fabry-Perot(F-P)干涉仪监测溶液浓度微小变化量的传感装置.利用光纤传输激光并用分体CCD采集图像,实现对溶液浓度的高精度微变化量的实时监控和测量.从理论上分析了F-P干涉仪干涉条纹的改变数目Δk与溶液浓度微变化量Δc(Δk)之间的关系,采用平面F-P干涉仪实现高精度测量溶液浓度微变化量的原理和可行性.在实验上构建了由He-Ne激光器、石英光纤、平面F-P干涉容器腔、面阵分体CCD、计算机等组成的实验监控与测量装置,对三组不同浓度的甘油溶液进行测量,通过观察干涉条纹的改变数目测定溶液浓度的改变量,用实验结果标定溶液浓度微变化量Δc(Δk)与干涉条纹改变数目Δk之间的数学解析式.实验结果表明:采用该系统可以监测到10-4量级的溶液浓度的变化值.

A real-time solution concentration monitor based on Fabry-Perot interferometer is designed.The concentration variation measurement is realized by the F-P interferometer and optical fiber to transmit the image to the CCD.The relation between the variation of interference fringes of the F-P interferometer and the fluctuation of solution concentration is analyzed.The monitor system consists of He-Ne laser,optical fiber,planar F-P interferometer,arrayed CCD and PC is set up.Three different glycerin solution are used to verify the system design,and the experiment shows the system can provide a resolution on the order of 10-4 concentration variation.