外差干涉仪非线性相位补偿方法及其实现技术的研究

发布时间：2018-06-23 08:12

  本文选题：外差干涉仪 + 非线性　； 参考：《上海大学》2015年博士论文

【摘要】：外差激光干涉仪是20世纪70年代初发展起来的测量仪器,它能以简单的相位比较测量达到很高的准确度,而且结构简单、抗干扰能力强、同时检测方便,所以它在精密测量技术领域中扮演着重要的角色。进入21世纪,随着微电子、微机电系统和超精密加工等技术的迅速发展,亚微米到纳米精度的测量已经成为迫切需要解决的问题。对于纳米范围的测量,外差激光干涉仪具有独特的优势,但其本身固有的非线性误差使其难以实现纳米精度的测量。因此,外差干涉仪非线性补偿方法与技术的研究是当今一个重要的课题。本论文通过对椭圆偏振光在外差干涉仪光臂中产生混频现象以及相位比较原理的研究,明确地给出了线性相位移、非线性相位移和干涉仪非线性的定义以及干涉仪两个基本的测量关系。通过理论分析和定量测试研究了各种可能的光学原因对非线性相位移的影响。在研究外差干涉仪非线性相位移模型和基本测量关系的基础上,提出了一种基于相位补偿的非线性消除方法。对该方法进行了理论证明和确切的描述。进而研究了非线性相位补偿系统的性能和相位补偿方法实现的关键技术,并通过实验验证了该方法对消除外差干涉仪一阶或高阶的非线性误差是有效的。用这种简单的检测方法,非线性误差容易地从内部消除。论文的主要研究工作和成果有如下几个方面:1.从描述入射光的两个任意椭圆偏振光的公式入手,介绍了外差干涉仪的基本测量原理;通过对椭圆偏振光在干涉仪光臂中产生混频现象并导致非线性相位移的研究,确切地给出了线性相位移、非线性相位移和干涉仪非线性的定义;通过对非线性特征和相位比较原理的研究,给出了干涉仪两个基本的测量关系。2.通过理论分析和定量测试研究了各种可能的光学原因对非线性相位移的影响。重点分析了波片误差对非线性的影响,给出了“波片误差影响非线性的四点结论”;应用“双相位测量法”对不同的外差干涉仪非线性相位移进行了测试,并得出了外差干涉仪非线性的数量界限(非线性误差可达十几至二十个纳米左右)。3.在研究外差干涉仪非线性相位移模型和基本测量关系的基础上,提出了一种基于相位补偿的非线性消除方法并对该方法进行了理论证明和确切的描述。该方法的实质是依据相位差信号通过控制位于干涉仪光电接收器前面的偏振片按设定方向旋转相应角度,而实现对非线性相位移的补偿,最终达到消除干涉仪非线性误差的目的;从分析二向色性偏振片的特性入手,对非线性相位补偿方法进行了分析,给出了具有相位补偿的非线性相位移的数学模型,给出了偏振片旋转角度与补偿非线性相位移的规律与关系。4.通过对光路结构的分析,给出了干涉仪在理想状况和实际状况下,随着测量环境和测量进程的变化,干涉仪相位误差的分布。通过对干涉测量系统的分析研究,给出了系统输出与输入关系以及偏振片旋转的角速度与拍频的关系。通过对系统中主要光学元件特性的分析,给出了激光光源、普通分光镜、偏振分光镜、角锥棱镜、1/4波片和偏振片的选型。5.根据非线性相位补偿方法的基本原理,设计了试验系统的硬件框架和测控系统主程序的流程图。设计了电流环PWM伺服放大器和PID控制器。建立了偏振片伺服控制系统的模型并研究了基本特性。6.对非线性相位补偿方法进行了验证性的实验研究工作。设计了实验平台,分别给出了无相位补偿试验和有相位补偿试验的方法。给出了试验数据及处理的方法,并对试验结果进行了分析与总结。
[Abstract]:Heterodyne laser interferometer is a measuring instrument developed at the beginning of the 1970s. It can achieve high accuracy with simple phase comparison measurement, and it has simple structure, strong anti-interference ability and convenient detection. So it plays an important role in the precision measurement technology field. In twenty-first Century, with microelectronics and microelectromechanical systems The measurement of submicron to nanometer precision has become an urgent problem to be solved in the rapid development of ultra precision machining and other technologies. For the measurement of nano scale, heterodyne laser interferometer has unique advantages, but its inherent nonlinear error makes it difficult to measure the nanometer precision. Therefore, the heterodyne interferometer is nonlinear complementarity. The research of compensation method and technology is an important topic. Through the study of the phenomenon of mixing frequency of elliptically polarized light in the optical arm of heterodyne interferometer and the principle of phase comparison, the relationship between linear phase shift, nonlinear phase shift and interferometer nonlinearity and the two basic measurement relations of interferometer are given. The effects of various possible optical reasons on the nonlinear phase shift are studied by theoretical analysis and quantitative testing. On the basis of the study of the nonlinear phase shift model and the basic measurement relation of the heterodyne interferometer, a nonlinear elimination method based on phase compensation is proposed. The key technology of the performance of the nonlinear phase compensation system and the implementation of the phase compensation method is investigated. It is proved by experiments that the method is effective for eliminating the first or high order nonlinear errors of the heterodyne interferometer. The nonlinear error is easily eliminated from the inner part with this simple method. The main research work and results of the paper are the results of the paper. The following aspects are as follows: 1. the basic measurement principle of the heterodyne interferometer is introduced from two arbitrary elliptic polarized light formulae describing the incident light, and the study of the nonlinear phase shift of the elliptically polarized light in the interferometer optical arm leads to the exact linear phase shift, the nonlinear phase shift and the interferometer. Linear definition; through the study of nonlinear characteristics and phase comparison principle, two basic measurement relations of interferometer.2. are given. The influence of various possible optical reasons on the nonlinear phase shift is studied by theoretical analysis and quantitative test. The influence of wave plate error on the nonlinearity is analyzed, and the influence of wave plate error is given. The nonlinear phase shift of different heterodyne interferometers is tested by using the "two phase four point" method. The nonlinear phase shift of the heterodyne interferometer is obtained, and the nonlinear phase shift model and the basic measurement relation of the heterodyne interferometer are studied by the nonlinear error of the heterodyne interferometer (the nonlinear error can reach more than ten to twenty nanometers).3.. On the basis of this, a nonlinear elimination method based on phase compensation is proposed and a theoretical proof and exact description of the method are made. The essence of this method is to compensate for the nonlinear phase shift by controlling the phase difference signal to rotate the corresponding angle in the setting direction by controlling the polarizer in front of the interferometer photoelectric receiver. Finally, the purpose of eliminating the nonlinear error of the interferometer is achieved. From the analysis of the characteristics of the two chromatic polarizer, the nonlinear phase compensation method is analyzed. The mathematical model of the nonlinear phase shift with phase compensation is given. The law of the rotation angle of the polarizer and the compensation for the nonlinear phase shift is given and the relation.4. is passed through the light. The analysis of road structure gives the distribution of interferometer phase error with the change of measuring environment and measurement process in ideal condition and actual condition. Through the analysis and study of interference measurement system, the relationship between the output and input of the system and the relationship between the angular velocity of the polarizer rotation and the beat frequency are given. In order to analyze the characteristics of optical elements, the laser light source, ordinary optical splitter, polarization splitter, pyramid prism, 1/4 wave plate and polarizer are selected.5. according to the basic principle of the nonlinear phase compensation method, the hardware frame of the test system and the flow chart of the main program of the measurement and control system are designed. The current loop PWM servo amplifier and the PID control are designed. The model of the polarizer servo control system is set up and the experimental research on the basic characteristic.6. has been studied. The experimental platform is designed, the phase compensation test and the phase compensation test are given respectively. The test data and the method of processing are given, and the test results are also given. The analysis and summary are carried out.
【学位授予单位】：上海大学
【学位级别】：博士
【学位授予年份】：2015
【分类号】：TH744.3
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本文编号：2056457