摘要
本文提出了一种基于光纤位移测量的液体折射率测量方法。首先,采用激光干涉法设计了液体折射率测量的光学系统,并基于激光散斑消除理论,设计了针孔滤波器合理消除散斑,提高了系统的抗干扰能力;其次,对测量系统中的位移测量方法进行分析和研究,提出了一种光纤式位移测量方法,并设计应用反射式光纤位移传感器,取消传统的条纹计数,实现了位移的高精度测量,其测量分辨力可达微米级;再次,采用机械位移驱动系统,驱动光学系统元件移动来实现光程差的自动变化,其驱动分辨力可达纳米级;最后,搭建液体折射率总体测量演示验证系统,以纯水、溶液为实验对象,其所需待测样品的容量少于0.001ml。实验结果表明:纯水折射率的测量精度可达1.5×10-3,溶液折射率测量精度可达2.1×10-3,表明该测量方法可实现液体折射率的非接触、高精度、智能测量。
This paper presents a liquid fiber displacement measurement method for m easuring the refractive index.Firstly,the laser interferometry is used to design optical measuring system of refractive index of liquid,and based on the elimination of laser speckle theory,a pinhole filter designed to eliminat e speckle reasonable is and further improve the system′s anti-jamming capabil ity.Secondly,after analyzing the displacement measurement methods the measurement system in, we propose a fiber optic displacement measuring method,and apply fiber optic displacement sensor for eliminating the traditional fringe counting to achieve high-precision measurement of displacement.The measurement resolution can reach up to micron level.Thirdly stepper motor drive system is used to drive the optical system elements to implement an automatic change of optical pat h difference,and the driving resolution may nanometer grade.Finally,the overall measurement system is built for measuring the refractive index of liquid with w ater and solution as experimental subjects.The capacit y of the measured sample is less than 0.001mL.The experimental results show tha t refractive index measurement precision of pure water can reach 0.0015,and refractive rate measurement precision of NaCl solution can reach 0.0021,which shows that the measurement method can realize non contact,high precision,intelligent measurement of liquid refractive index.
出处
《光电子．激光》
EI
CAS
CSCD
北大核心
2016年第12期1311-1319,共9页
Journal of Optoelectronics·Laser
基金
国家自然科学基金(51505078)资助项目
关键词
液体折射率
激光干涉
位移测量
光纤
智能
liquid refractive index laser interference
displacement measurement, optical fiber
intelli-gence
