基于双弹光级联差频调制的波片参数测量研究  

Waveplate Parameter Measurement Based on Dual Photoelastic Modulators Cascade Differential Frequency Modulation

作　　者：王爽 崔志英[2,4] 冯华君 李克武 王志斌[3] WANG Shuang;CUI Zhiying;FENG Huajun;LI Kewu;WANG Zhibin(School of Data Science and Technology,North University of China,Taiyuan 030051,China;Ningbo Yongxin Optics Co.,Ltd,Ningbo 315040,China;Engineering and Technology Research Center of Shanxi Province for Opto-electric Information and Instrument,North University of China,Taiyuan 030051,China;College of Optical Science and Engineering,Zhejiang University,Hangzhou 310014,China)

机构地区：[1]中北大学计算机科学与技术学院,太原030051 [2]宁波永新光学股份有限公司,宁波315040 [3]中北大学山西省光电信息与仪器工程技术研究中心,太原030051 [4]浙江大学光电科学与工程学院,杭州310041

出　　处：《光子学报》2023年第11期182-191,共10页Acta Photonica Sinica

基　　金：国家自然科学基金(Nos.62205309,62205310)。

摘　　要：为了实现对波片快轴方位角和延迟量参数快速、高精度测试,提出了一种基于双弹光级联差频调制的波片参数测量方案。选用两个工作频率不相同的弹光调制器级联,构成偏振分析测量装置。波片的两个参数被加载到偏振分析装置的调制信号中,采用数字锁相技术同时提取调制信号的基频项和差频项,然后完成波片全部参数求解。按照原理分析,搭建了实验系统,并完成了系统初始偏移值定标,完成了632.8 nm的1/4波片,532 nm的1/4波片和1/2波片实验测量。实验结果表明,本文方案的快轴方位角测量最大偏差为0.2°,角度测量标准偏差为0.02°;波片的相位延迟量标准偏差优于5.64×10^(-4)rad,单点数据测量时间仅为200 ms。考虑到波片材料的双折射色散,根据检测激光波长下测量的相位延迟量,进一步计算出应用波长的波片延迟量。测量值与理论值最大偏差不超过1.17 nm,延迟精度优于λ/300。本文方案实现了高速、高精度和高灵敏的波片参数测量,可为波片加工测试和实验定标提供有效手段。A waveplate is a basic optical component manufactured based on birefringence.It is typically made of quartz crystals,MgF2 crystals,or polymers with tens of micrometers thickness.A waveplate is used to change the polarization state.It is mainly employed in polarization generating devices and polarization analysis devices.It plays an important role in the fields of communication,sensing,and optical storage.The fast-axis azimuth and retardance are the key parameters of the waveplate.Accurate measurement and calibration of the two parameters are key steps in the manufacturing process of the wave plate.These steps directly determine the performance of the polarization optical system using the waveplate.Now,methods such as light intensity,polarization compensation,interferometry,laser feedback,and polarization modulation techniques,are applied to research the measurement of parameters of waveplate.Nevertheless,measurement speed and accuracy still need to be further improved.For the needs of rapid and high-precision parameter measurement of waveplate,a measurement scheme based on dual photoelastic modulators cascade difference frequency modulation is proposed in this paper.Considering the application advantages of photoelastic modulation,such as high modulation frequency,large optical aperture,high modulation purity and stable operation et al.,a novel measurement method using photoelastic modulation is proposed.A simple polarimetry is constructed based on two photoelastic modulators with differential modulation frequencies.The phase retardation and fast axis azimuth angle are loaded into the differential frequency photoelastic modulation signals,and the digital phase-locked technology is used to extract the differential frequency harmonic terms and fundamental frequency harmonic terms of photoelastic modulation at the same time,so as to further solve the phase retardation and fast axis azimuth angle.The principle of the new scheme is analyzed,and an experimental system is built.The initial offset value of the system is

关 键 词：弹光调制 差频调制 波片 快轴方位角 延迟量 

分 类 号：O436.3[机械工程—光学工程]