基于AD8302的双纵模双频激光干涉仪信号处理系统

为了解决双纵模双频激光干涉仪原有信号处理电路两路信号易直流漂移、不正交对干涉仪系统测量精度和速度的限制及调整光路观察信号不方便等问题,利用AD8302的良好高频处理特性,设计了一种新的基于AD8302的双纵模双频激光干涉仪信号处理系统,给出了方案的总体框图和信号处理流程图,详细地分析了其工作原理以及提高相位测量精度方法.由于器件相位测量的高分辨率,该系统也可用于高分辨率双纵模双频激光轮廓仪的信号处理.     

一种应用于激光干涉仪的等比例偏移定量准直装置

设计一种用于激光干涉仪的等比例偏移定量调整的准直装置,利用该装置可以方便快捷、精准定量、一次性实现光路准直。实验表明:对于校准坐标测量机单轴6 m的定位误差,利用该装置调整准直光路的方法只需要调整一次,所用时间小于2 min。     

基于等比例偏移定量调整的光路准直方法

激光干涉仪广泛应用于位移、角度、平面度、直线度、垂直度等领域的测量,在使用过程中传统的光路准直调整方法费时费力,无章可循全凭经验,耗费检测人员大部分精力。该文提出基于等比例偏移定量调整的准直光路方法,提高光路准直调整效率,检测人员可以方便快捷、精准定量、一次性的实现光路调整。     

"共光路"校准激光干涉仪的测长不确定度

激光干涉仪校准时为了避免引入阿贝误差,通常采用"背对背"测量方法,即标准干涉仪的反射镜与被测干涉仪的反射镜背对背放置,使标准干涉仪与被测干涉仪的光路处于同一直线上.现提出校准激光干涉仪的另一方法,利用同一组分光镜和反射镜,使标准干涉仪与被测干涉仪的光路处于同一光路上,即"共光路"测量方法.这种方法与"背对背"的测量方法相比,具有抗环境干扰的能力强的优点,使由环境条件引入的测量误差最小,其最佳相对测量不确定度优于1×10-7.通过测量数据和标准测量装置的不确定度分析,来评价"共光路"测量方法的优越性.     

双频激光干涉仪测量竖直轴光路调整实践

本文针对双频激光干涉仪在进行各种机床、风洞运动机构等竖直轴位置精度校准时,光路调整复杂,工作效率较低,测量精度难以保证等问题,在充分分析了光路调整工作原理的基础上,设计加工了一种竖直轴专用光路调整台,并成功应用于实践,缩短了光路调整时间,极大提高了工作效率。     

用激光干涉仪检测双丝杠驱动加工中心的方法与评定

介绍了使用激光干涉仪检测双丝杠驱动加工中心时,选择测量轴线的有效位置,能够真实地反映加工中心轴线的运动定位状态;提出检测双丝杠驱动加工中心定位精度和重复定位精度的方法,通过调整激光干涉仪和位移镜组件的安装位置,获得数控机床及加工中心的检测精度,并根据自动采集获得的测量数据进行有效地补偿,以提高和恢复数控机床及加工中心的最佳定位精度.     

激光干涉仪线性测量的光路准直调整方法

本文首先概述了XL-80双频激光干涉仪对中国一拖集团有限公司的数控机床的周期检测的必要性和意义,随后简单介绍了XL-80激光干涉仪线性测量硬件配置和工作原理,最后详细介绍了两种激光干涉仪线性测量的光路准直方法。     

外差干涉仪频率混叠误差分析

研究了激光外差干涉仪中存在的频率混叠现象、误差形成机理和变化规律,重点分析了在共光路外差干涉仪中由激光光源的椭圆偏振化和Ｗｏｌｌａｓｔｏｎ棱镜的安装方位角引起的频率混叠误差的大小及变化规律,对进一步提高共光路外差干涉测量精度具有现实意义。     

利用激光干涉仪对重大型数控机床两线性轴间垂直度测量方法的探索

通过对激光干涉仪各项检测功能的深入研究和大量测试试验,利用激光干涉仪开发出重大型数控机床两线性轴间垂直度测量的两种新方法。本文重点描述直角尺法、激光干涉仪对角线法、激光干涉仪垂直度镜组法测量两线性轴间垂直度的原理、方法和注意事项,并对三种测量方法进行了比对分析。     

基于光路折叠的室内基线场误差分析方法研究

为了有效开展长距离光电测距类仪器的室内检定工作,在50m高精度导轨上利用1组平面反射镜进行光路折叠,搭建了100m室内基线场。对基线系统的测量误差进行了分析,考虑各项误差的调整精度,将误差分析结果应用到实际光路调整过程中,分析得到对基线长度影响更显著的误差量,并对其进行了控制和调整,提高测量光路的平行性调整精度,最后选择双频激光干涉仪作为长度基准开展验证实验。实验结果表明:通过光路折叠方法可以实现2倍光程倍增,基线系统的精度较高,可进行连续测量,有效地解决了室内基线建立过程中所存在的检测效率低、可重复性差等技术问题。     

激光偏振干涉光路的非线性分析计算

偏振干涉光路两臂光程差的变化和合成干涉信号的相位变化，理论上具有线性关系，可以对引起光程差的任何微小量进行测量。实际上光路光学元件性能及调整并不理想，形成了二者的非线性关系。本文分析计算了各光学元件形成的非线性及这些元件综合形成的非线性，给出了适用于各种情况下的计算公式，并提出了光路的调整方法。     

Separation of measurement of the refractive index and the geometrical thickness by use of a wavelength-scanning interferometer with a confocal microscope

An improved system for the separate measurement of the refractive index and the geometrical thickness that constitutes a hybrid configuration of a confocal microscope and a wavelength-scanning heterodyne interferometer with a laser diode is presented. The optical path difference can be measured in less than 1 s, which is 10 times quicker than with the low-coherence interferometry previously used, and with a resolution of 10 mum with a fixed reference mirror. Separate measurement of the refractive index and the geometrical thickness of glass plates was demonstrated by use of the arrangement in place of the low-coherence interferometer used previously.     

一种用于线膨胀系数测量的高稳定性激光干涉系统

介绍了一种可以对材料长度变化进行测量的高稳定性双光程激光干涉系统,由于该干涉系统的测量光路和参考光路具有相似的传播路径,光程差仅由被测试样的长度引起,干涉系统具有较强的抵抗环境温度变化和振动等外界干扰的能力。通过平晶反射膜测量试验,对干涉系统的稳定性进行了验证,结果表明在6. 5 h内测量数据的标准偏差为4. 2 nm。该激光干涉系统可用于材料尺寸变化(如线膨胀系数)的高准确度测量。     

Interferometer for optical coupling and mode selection in a multichannel laser array

A theoretical consideration is presented of the optical coupling and selection of laser array modes by the use of a developed Lummer-Gehrcke interferometer as a resonator reflector. Control of the mirror reflection of the proposed interferometer permits laser power to be redistributed through channels on the outlet resonator mirror; in particular, it makes it possible to lead power out of the resonator by a single beam. In this way it is possible to diminish the sidelobes in the far-field radiation profile of multichannel lasers and to raise the efficiency of the optical coupling of the laser array with waveguides and fibers. This method may be used for the redistribution of laser power on the outlet mirror in striped lasers as well.     

一种新型单频激光干涉系统的研究

这种单频激光干涉系统采用共光路设计布局,通过偏振分束器以及1/4波长片等光学器件对干涉条纹进行空间移相,提取相位依次相差90°的三路干涉输出信号,进行比较放大,解决了常规单频激光干涉仪中的光强“零漂”问题。利用共模抑制技术,提高了干涉系统的测量稳定性和重复性。采用光程差放大技术,提高了干涉系统的分辨力。     

Surface profilometry with laser-diode optical feedback interferometer outside optical benches

A simple and robust interferometer with a laser diode subject to optical feedback from the interferometer is presented for surface testing of a spherical mirror. The fringe phase can be locked by the optical feedback within less than 0.2pi (peak-to-valley value) even when the interferometer is placed on a wooden table. The fringe locking is caused by the change of lasing wavelength that suppresses the net phase change to be much less than 2pi. The locked fringe pattern with spatial carriers can be analyzed by a fringe analyzer at a video rate, and the measurement results of the spherical mirror showed the same result as on an optical bench.     

Principle of the moving-mirror-pair interferometer and the tilt tolerance of the double moving mirror

A novel type of interferometer, the moving-mirror-pair interferometer, is presented, and its principle and properties are studied. The new interferometer is built with three flat mirrors, which include two flat moving mirrors fixed as a single moving part by a rigid structure and one flat fixed mirror. The optical path difference (OPD) is obtained by the straight reciprocating motion of the double moving mirror, and the OPD value is four times the physical shift value of the double moving mirror. The tilt tolerance of the double moving mirror of the novel interferometer is systematically analyzed by means of modulation depth and phase error. Where the square aperture is concerned, the formulas of the tilt tolerance were derived. Due to the novel interferometer's large OPD value and low cost, it is very applicable to the high-spectral-resolution Fourier-transform spectrometers for any wavenumber region from the far infrared to the ultraviolet.     

Phase noise characteristics of a diode-pumped Nd:YAG laser in an unbalanced fiber-optic interferometer

The measurement sensitivity of interferometric fiber sensors can be limited by the laser phase noise. We investigate the phase noise characteristics of a diode-pumped Nd:YAG laser in an unbalanced fiber-optic interferometer. Measurements were made of the phase-induced intensity noise of an interferometer with varying optical path differences. The experimental results of the relation between the noise and the optical path difference are given, and the application of the results in the design of a fiber-optic accelerometer is discussed.     

Fourier transform near-infrared spectrometer using a corner-cube integrated prism scanning interferometer

This paper describes a Fourier transform (FT) near-infrared spectrometer that uses an integrated prism scanning interferometer whose optical paths are stabilized by corner cubes. A combination of corner cubes and a retroreflection mirror, which is sometimes used in the conventional interferometer for FT spectrometers, is adopted and adapted to the integrated prism scanning interferometer through a special design. Without any degradation of spectroscopic properties, the optical path in the interferometer is highly stabilized and the moving distance of the stage is halved. These advantages provide a robust and portable FT spectrometer for field use.