接触式干涉仪的数字化改造

为解决接触式干涉仪使用过程中对线不准、人工读数误差大等问题，采用图像采集与处理技术对其进行数字化升级改造。使用工业相机，将实时采集的干涉条纹图像传输至计算机，同时基于灰度投影法，实现自动定度与零级干涉条纹中心的定位，根据零级干涉条纹中心的偏移量，计算被测量块与标准量块的差值，并将相关测量信息自动存储至数据库。实验表明：改造后的接触式干涉仪性能稳定可靠，能准确计量检校三等及以下的量块长度。     

接触式干涉仪工作台平面度在量块长度测量中引入误差的探讨

通过JJG 101-2004《接触式干涉仪》和JJG146-2011《量块》检定规程,本文探讨了接触式干涉仪工作台平面度在量块长度测量中的引入误差,结果显示使用接触式干涉检定量块长度时,在极端条件下,工作台平面度引入的误差较大,可能会影响量块的合格评定。     

干涉条纹小数的测量

对高精度干涉条纹小数测量的方法进行了系统的介绍.就干涉条纹小数的定义、暗条纹中心的确定、量块中心长度测量的起始和终了位置进行了较全面的分析,实现了不确定度为2 nm的干涉条纹小数的测量.引用实验与国际比对结果理论分析予以验证.     

新型移相量块干涉仪的研制

研制了一台用于0.5~100 mm量块测量的新型移相量块干涉仪,分别以波长为633 nm和543 nm的两台稳频激光器作为测量光源,通过一根单模光纤引入到干涉仪内。高精密移相器实现5步移相干涉测量,CCD相机采集干涉条纹并计算干涉条纹小数,被测量块长度采用多波长的小数重合法计算。移相量块干涉仪的测量不确定度达到U=0.015μm+0.07×10~(-6)L(L为量块长度,mm)。     

立式接触式干涉仪的核查方法及异常值排查

<正>立式接触式干涉仪是三等量块标准装置的主要配套设备,在量块检定过程中,立式接触式干涉仪通过对标准量块与被检量块的微差比较法,取得被检量块的修正值。因此,在检定前对立式接触式干涉仪进行有效的核查,是排除异因、保证检定数据真实准确的基础。笔者现结合多年工作经验,对立式接触式干     

接触式干涉仪的调整和修理

0引言 接触式干涉仪是以光波干涉原理为基础，采用微差比较法测量长度的高准确度仪器。主要用于检定尺寸小于150mm的2等和2等以下的量块，也可对其他高准确度零件进行测量或作高准确度定位。在一般计量部门．接触式干涉仪较多地使用于检定和校准3、4等量块。     

对接触式干涉仪检定规程第19条规定的探讨

通过接触式干涉仪示值误差检定的方法误差分析以及新的三等量块比较法检定的误差分析，探讨用新的三等量块配对检定接触式干涉仪示值误差的可行性。     

3等量块中心长度校准结果不确定度评定

本文以新规程《JJG146-2003量块》为依据,对三等量块在接触式干涉仪上检定中心长度校准结果的不确定度分析、评定.     

长度计量基础知识讲座(二十七) 第二十七讲 接触式干涉仪

1概述接触式干涉仪(以下简称干涉仪)是应用光波干涉原理,采用微差比较测量法测量长度的高精度计量仪器。干涉仪由前苏联计量仪器专家乌威尔斯基设计并制造,因此通常称为乌氏干涉仪。干涉仪主要用于检定尺寸小于150mm的3等及以下量块的尺寸,也可以对其他高精度零件进行精密测量或作高精度测量的定位。     

长度计量基础知识讲座(二十七)

1概述接触式干涉仪(以下简称干涉仪)是应用光波干涉原理,采用微差比较测量法测量长度的高精度计量仪器。干涉仪由前苏联计量仪器专家乌威尔斯基设计并制造,因此通常称为乌氏干涉仪。干涉仪主要用于检定尺寸小于150mm的3等及以下量块的尺寸,也可以对其他高精度零件进行精密测量或作高精度测量的定位。     

基于光纤干涉仪的振动测量技术

本文介绍了基于光纤Mach-Zchndcr干涉仪的振动测量系统,用线阵CCD测量条纹动态位移,实现了光纤干涉条纹图像的连续采集.针对干涉条纹图像噪声的特点完成了低通滤波器的设计、图像的平滑处理,消除了干涉条纹中心的定位误差.文章绘制了干涉条纹位移曲线并对其进行了离散傅里叶变换,给出了所测振动的频谱特性.最后讨论了测量系统的灵敏度以及影响测量精度的因素,为了能够辨别条纹的移动方向,指出了条纹最大允许的移动速度限制,给出了实验结果.     

Method to obtain a clear fringe pattern with a zone-plate interferometer

When a zone-plate interferometer is used, a bright spot appears at the center of the image plane. The spot makes it difficult to analyze the interference fringes. A simple technique that is based on the principle of fringe-intensity reversal is proposed to analyze the fringes efficiently. A zone plate with a phase fraction of π/2 or 3π/2 is used in this technique to diminish the bright spot. Unlike the masking technique, no part of the data on the fringes is lost. The fringes can, therefore, be analyzed completely. The technique is described in detail, and the results of an experiment in which the shape error of a concave mirror was measured with the proposed zone plate is presented. The experimental results agree well with the results obtained with the Fizeau interferometer.     

Approach for the evaluation of speckle deformation measurements by application of the wavelet transformation

We introduce a new, to our knowledge, method using wavelets and probability theory for the evaluation of speckle interference patterns for quantitative out-of-plane deformation measurements of rough surfaces of nontransparent solids. The experiment uses a conventional Twyman-Green interferometer setup. The speckle interference patterns are obtained by the common method of subtraction of images taken before and after a surface deformation. The data are processed by a wavelet transformation, which analyzes the image structures on different length scales. Thus it is possible to separate the interference fringes from the noise. From the locations of the interference fringes, the deformation of the surface can be reconstructed by means of probability theory.     

Double-grating interferometer for measurement of cylinder diameters

We describe a double-grating interferometer for the measurement of cylinder diameters. The unique characteristic of this interferometer is that one can freely change the period of the interference fringes by turning the grating, which permits the measurement range of the interferometer also to be changed freely according to the cylinder diameter to be measured. A clear image of the cylinder can be obtained because the aperture diaphragm blocks the beams diffracted from the edge of the cylinder. The outside and inside diameters of the M4 x 0.7 mm hand tap are measured with this double-grating interferometer.     

相位扫描法制作变栅距光栅

提出了一种制作变栅距(VLS)光栅的相位扫描方法。该方法的主要装置包括一个用于控制刻划机运动的光栅干涉仪和一个相位扫描机构。如果调整光栅干涉仪,保证接收场中只有两条干涉条纹,然后改变用于对条纹进行计数的光电传感器的位置,就可以刻划出具有变栅距的刻槽。对光电式光栅刻划机的控制系统和结构都做了详细论述。按照上述方法成功刻划出了试验性的VLS光栅,它的最小栅距增量为0.33nm,并对在制作过程中产生的误差进行了讨论。采用测量衍射角的方法进行了栅距检测试验,由变栅距光栅和等栅距光栅作出的拟合曲线表明:相位扫描方法是加工具有亚纳米栅距增量的VLS光栅的有效方法,该方法对超精密定位也具有借鉴作用。     

Dispersive spectral-domain two-beam interference analysed by a fibre-optic spectrometer

Abstract

The effect of a fibre-optic spectrometer on analysed spectral interference of two beams from a white-light source is studied theoretically and experimentally, including the effect of dispersion in an interferometer. First, the spectral interference law is expressed analytically under the condition of a Gaussian response function of a fibre-optic spectrometer, and then second, the theoretical analysis is accompanied by three experiments employing a fibre-optic spectrometer and a Michelson interferometer with different amounts of dispersion. Within one experiment the interference fringes are resolved over a wide spectral range and within two experiments the interference fringes are resolved only in a narrow spectral range around a wavelength at which the group optical path difference between interfering beams is zero. Knowing dispersion in the interferometer and the bandpass of the spectrometer, the positions of the interferometer mirror in the corresponding range are determined and good agreement between the recorded spectral interferograms and the theoretical ones is found.     

Stability improvements for an interferometer through study of spectral interference patterns

Conventional Mach-Zehnder interferometer configuration is modified to enhance its stability from the vibrations. To study the effects of vibrations on the Mach-Zehnder interferometer, we used spectral interference fringes from a broadband nanosecond dye laser source. We observed an improvement in the stability of the interferometer by a factor of 3.     

Probing of a random phase object by a focused spatially modulated laser beam. Integral scanning method

A telescope system incorporating an illuminating spatially modulated laser beam, a diffuser in the entry plane, and a random phase screen in the spatial frequency plane was used to analyze the formation of average-intensity interference fringes in the image plane of the diffuser. It is shown that the system can operate as a shift interferometer where the contrast of the fringes is independent of the diffuser characteristics. Analytic expressions are obtained for the contrast of the fringes as a function of the parameters of the screen and the illuminating beam and it is established that the statistical anisotropy of the screen influences the contrast of the fringes. Pis’ma Zh. Tekh. Fiz. 25, 5–10 (December 26, 1999)     

Special features of Newton-type fringe formation in a diffraction interferometer

An interferometer with a Fresnel zone plate located in the center of curvature of a concave mirror was studied. Attention was paid to the unique features of the interference field, which has a special point at which the path difference is equal to zero, thereby allowing for the observation of Newton-type fringes in white and quasi-monochromatic light. The conditions necessary for reducing the instrumental error to values less than lambda/20 were determined. Methods for suppressing noise and destructive interference patterns were also found. Metrological tests were carried out, and they proved the possibility of using this interferometer for industrial testing of spherical and parabolic mirrors.     

平晶检定时干涉条纹的快速调整方法与平面度计算

在平面等厚干涉仪上检定平晶工作面平面度时,需要在被检区域调整出3到5条干涉条纹,依据测量原理和计算公式求出被检平晶工作面的平面度.文章重点分析干涉条纹的快速调整方法与标准平晶平面度的正确引用方法.