利用光栅的衍射光强测量液体折射率  

MEASUREMENT OF LIQUID REFRACTIVE INDEX BASED ON OPTICAL GRATING DIFFRACTION

作　　者：李长乾 王立英 LI Changqian;WANG Liying(Department of Applied Physics,Faculty of Science,Tianjin University,Tianjin 300354;Tianjin Demonstration Center for Experimental Physics Education,Tianjin 300354)

机构地区：[1]天津大学理学院应用物理学系,天津300354 [2]天津大学理学院物理市级实验教学示范中心,天津300354

出　　处：《物理与工程》2022年第5期121-126,共6页Physics and Engineering

摘　　要：介绍了一种利用光栅的一级衍射光斑光强测量待测液体折射率的方法,简称光栅光强法。阐明了光栅光强法测量液体折射率的实验原理,组建实验装置,测量了水丙三醇、蛋白pH10缓冲液两种混合液体的折射率和光栅衍射光强的关系曲线,测量得到的无水乙醇的折射率与理论值的相对误差小,具有实验装置易于搭建、操作简单的特点,在实验教学研究等领域具有一定的研究和应用价值。This paper introduces a method to get liquid refractive index by measuring the light intensity of the first-order diffraction spot of the grating,which is called the grating light intensity method.The experimental principle of measuring liquid refractive index by the grating light intensity method is expounded.An experimental set-up was designed to measure the relationship between the refractive index and first order intensity for water-glycerin and egg white-pH10 buffer.The relative error between the measured refractive index of absolute ethanol and the theoretical value is small.Furthermore,the experimental device is easy to be built and convenient for use.It has potential applications in the field of experimental teaching and other related research fields.

关 键 词：光栅衍射 一级衍射光强 液体折射率 

分 类 号：O436.1[机械工程—光学工程] O435.1[理学—光学]