利用梯形液膜干涉法实现液体浓度的自动检测

Automatic Measurement of Liquid Concentration by Transmission Interferometry

基于折射定律和等厚干涉原理设计了利用梯形液膜干涉法实现液体浓度的自动检测实验,通过AutoCAD软件测量和基于OpenCV-Python图像处理技术两种测量手段,对比计算空气环境和液体环境下干涉条纹尺寸,得到液体折射率,再定标其浓度值。以酒精溶液为例,采用自制微型梯形玻璃容器、透镜、毛玻璃、烧杯、量筒、激光器、电脑和CCD相机等仪器进行测量,即可得到液体浓度。通过实验表明,实验结果与经验公式吻合,两种测量手段各有优势,具有一定的推广价值。

Based on the empirical formula of liquid concentration and refractive index at room temperature,the home experiment of liquid concentration measurement by transmission interferometry is designed.With the principle of wedge equal thickness interference,the size of interference fringes in air and liquid is calculated,respectively.Then the liquid refractive index is calculated by the ratiOof the stripe intervals in air and in liquid.In the experiment,self-made trapezoidal glassware,lens,thin paper,beaker,measuring cylinder,semiconductor laser pen,computer and CCD camera are used.The liquid concentration can be measured by equal thickness interferometry.The experiment shows that the experimental results are consistent with the empirical formula,and the experiment can be used as a supplement to the online experimental teaching project.