实时全息干涉位移测量的自动化

实时全息干涉法可以观察记录整个测试过程中条纹图的动态变化,在传统的位移测量应用中只能通过条纹的变化给出定性分析结果。简述了实时全息干涉法进行微小位移测量的原理,根据实时全息干涉条纹和希尔伯特变换的特点,提出了利用希尔伯特变换法进行实时全息干涉位移测量的定量分析方法。实验表明：利用希尔伯特变换法可以自动提取实时全息干涉测量过程中全场各点在任意两个时刻间的相位变化傅,从面塞零位移测量鲍自动化、定量化。     

利用单模光纤实现干涉条纹实时控制

本文利用单模光纤输出端的微小位移实现了全息干涉条纹的实时控制。解决了利用全息干涉测量法测量物体变化时,由于刚体变形过大使全息干涉条纹判读困难等问题。     

数字全息中几种消零级方法的比较及改进

数字全息再现像中,零级衍射的存在影响了再现像的成像质量。在对几种简单消零级方法利弊分析的基础上,提出了一种定域灰度值非线性变换法。该方法不需要其他光学元件和额外的操作,即可以增强全息干涉图像的条纹对比度,同时消除零级衍射和背景噪声。将其应用在全息干涉术测量物体微小位移的实验中,成功消除了零级衍射的干扰,获得了高对比度的干涉条纹,并实现了物体微小位移的高精度测量。     

利用激光测量弹性薄板动态响应研究

采用动态全息干涉法,对弹性薄板受水中冲击波作用下的动态响应进行了研究。采用 红宝石双脉冲激光器,实现了动态全息干涉法测量,即两次曝光全息干涉法。设计了反射式动态干涉全息法测量光路,测量了弹性薄板受水中冲击波作用产生的横向变形(弯曲波) ,根据爆炸后不同时间的干涉条纹图,求出了挠度分布图。     

云纹干涉法测量铁电陶瓷的离面位移

文章采用反射式高灵敏度离面云纹干涉法测量了铁电陶瓷的离面位移。在铁电陶瓷上复制了每毫米１２００位相型闪耀光栅的试件栅；采用迈克尔逊干涉光路、全息干版照相、ＣＣＤ摄像机及其微机实时图像处理系统获取了试件表面的离面位移场的干涉条纹图。     

用参考物体全息法测量位移矢量方向

本文提出了一种测量物体位移矢量方向的方法一参考物体全息法，该方法将一个参考物体置于被测物体的一侧，然后在一张干版上记录两个双曝光全息图：一个是受到干版位移调制的被测物体和参考物体的双曝光全息图，一个是被测物体的非调制干涉图。前者用于测量位移矢量的方向，后者用于测量被测体位移的数值场。文中主要介绍了参考物体全息法测量位移矢量方向的原理。文后给出了实验结果。     

植物瞬时运动的全息干涉测量术分析

全息干涉测量术是一种照相技术，可用来测量物体的微小位移。威廉斯示出了着色麦苗的全息干涉照片，但在他最初的工作中，既未试图对植物的位移，也未试图对更为重要的植物的瞬时反应，作定量测量。我们的工作表明，若示出以前不可得的关于成熟的、慢移动的植物的弯曲和短期瞬时反应的数据，全息干涉测量术是可能用于植物运动分析的。我们的结果认为，全息干涉测量技术可以提供准确地测量诸如速度和位移等重要的植物运动参量的方法，它的分辨率比现有任何别的方法都高很多。此外，此技术实质上改进了植物运动分析的时间分辨率，因而可能更详细地观察随时间变化的光色互变反应。     

全息干涉法与斑纹干涉法相结合测量物体三维微小位移

本文介绍了在同一张双曝光的象平面全息图上测量物体三维微小位移的方法。其中离面位移用双曝光全息干涉法来测量,而面内位移则通过对该全息图中同时包含的迭加斑纹图样作光学傅里叶变换来测量。文中首先叙述测量的基本原理,然后给出一组实验结果。     

像全息双曝光干涉法在测量三维位移和位移导数以及轮胎无损探伤中的应用

本文介绍了像全息双曝光干涉法测量物体三维位移和位移导数的方法、原理及实验结果．给出了用真空内拍法检查轮胎和金属-橡胶粘合件内部脱层气泡缺陷的结果。     

用相对条纹级数法解释全息干涉图

本文提出一种解释全息干涉图的新技术——相对条纹级数法，实验结果与理论推导符合，因而从理论上解决了测量无零条皱大尺寸物体位移的问题。     

应用单张全息干涉图测定三维微小位移的一种快速算法

当前全息干涉计量总的发展趋势是光电结合以提高测量精度,利用计算机处理数据作定量计算提高速度.近几年来.笔者在这方面作了一些尝试.本文介绍借助于对双曝光全息图作多次观察来测定物体三维位移场的一种快速算法.由于处理方法的一般性,这种快速算法不仅可用于研究固体力学、精密机械,还可用于生物医学(例如口腔矫形、全息牙科术、骨胳变形及颅脑外伤等)的基础研究和临床实践.     

Strenge Lösung für einen piezothermoelastichen Streifen aus drei Schichten

Starting from the general three-dimensional relations of a piezothermoelastic body, the equations for the kinematical displacements, mechanical stresses and the electric displacement in a plate with the material behavior of a crystal of class mm2 are derived. Potential functions are introduced to represent the coupled elastic and electric fields in the plate. Simple uncoupled equations for the components of a generalized Galerkinvector and a generalized thermoelastic displacement potential function are derived. As an example, a strip with three layers is analyzed, and the boundary and interface conditions are given, which are needed for solving the equations in this case. The kinematical displacements and the distribution of the electric potential are represented graphically for various cases. The results may serve as benchmark solutions for numerical computations.     

Reconstruction of sequential cardiac in-plane displacement patternson the chest wall by laser speckle interferometry

Time-average speckle interferometry has been applied to obtain displacement patterns on the chest wall produced by cardiac action, in the absence of breathing, during various phases of the cardiac cycle. This has been achieved by an electronic shutter, controlled by the electrocardiogram of the subject. The recorded holographic plates processed under identical conditions are scanned by the pointwise method to obtain the absolute displacements at various locations corresponding to the activities of the various cardiac chambers and values. These data are transformed to a 40 x 30 matrix by an interpolation method and, from this, three-dimensional displacement plots are reconstructed by an IBM PC/AT computer. These patterns shown the displacements over the entire cardiac area corresponding to the activities of various regions during the cardiac cycle. The apex and aortic valve areas show the maximum displacements during the systolic phase. During the diastolic phase the activities over the low pressure atrial regions are also observed. The results obtained outline the functional details of the normal heart and the activities over various areas are in agreement with that of other noncontact techniques.     

Finite element analyses assisted Scanning Joule Expansion Microscopy on interconnects for failure analysis and reliability investigations

Thermo-elastic properties on aluminum interconnects are characterized by Scanning Joule Expansion Microscopy and complementary finite element analyses. Temperature distributions can be obtained by the correlation of the three-dimensional thermal expansion vectors and the device structure. Vertical and lateral displacements give access to thermally induced strains, which is important for advanced failure analyses on degradation processes.     

鼓形AT-切石英谐振器的力频特性

讨论了鼓形ＡＴ－切石英谐振器的力频特性。理论基础是初始有限变形上叠加弹性增量变形,并且使用了Ｍｉｎｄｌｉｎ所提出的把应变应力展开成板厚的级数的方法。在把三维运动方程简化为二维运动方程后。推导了带有电极的ＡＴ－切石英谐振器的运动微分方程。为了得到鼓形ＡＴ－切石英谐振器的Ｒａｔａｊｓｋｉ系数,在计算石英片在初始应力作用下的应力应变分布时考虑了石英各向异性的特性。将计算结果与其他研究者的实验和理论结果进行了比较。     

Integration of Radar Interferometry and Laser Scanning for Remote Monitoring of an Urban Site Built on a Sliding Slope

The alpine village of Lamosano, Belluno, Italy, located near a wide and active landslide, has been seriously threatened by ground instabilities since 1960. In this paper, the results obtained by two different remote-monitoring techniques, synthetic aperature radar interferometry and three-dimensional laser-scanner imaging, planned for Lamosano hazard assessment, are presented. Both techniques compare images taken at different times to map and classify changes that occurred on the imaged scenario. The radar and laser data are gathered at the same dates with about ten-month temporal separation. The displacements measured separately by each of the two techniques highlight a similar sliding motion on the Lamosano village area, providing a good validation to each other and contributing to the definition of the village instability hazard.     

Identification of translational displacements between N-dimensional data sets using the high-order SVD and phase correlation.

This paper presents an extension of the phase correlation image alignment method to N-dimensional data sets. By the Fourier shift theorem, the motion model for translational shifts between N-dimensional images can be represented as a rank-one tensor. Through use of a high-order singular value decomposition, the phase correlation between two N-dimensional data sets can be decomposed to independently identify translational displacements along each dimension with subpixel resolution. Using three-dimensional MRI data sets, we demonstrate the effectiveness of this approach relative to other N-dimensional image registration methods.     

含Rashba自旋轨道耦合二维电子气结构中电子反常位移及自旋分离

研究了含Rashba自旋轨道耦合的磁电调制半导体二维电子气中弹道电子的反常位移 （Goos-H?nchen位移,即GH位移）。计算中发现,通过调节结构的各个参数包括入射角、磁场强度和Rashba自旋轨道耦合系数,可以有效地调控GH位移,并且在一定条件下可以为负。电子的GH位移和自旋极化态有密切关系,这个自旋相关的位移可以用来分离不同自旋极化的电子束。基于这种现象,提出了一种利用GH位移在半导体2DEG中分离不同自旋极化电子的方法。     

Registration of 3-D intraoperative MR images of the brain using a finite-element biomechanical model

We present a new algorithm for the nonrigid registration of three-dimensional magnetic resonance (MR) intraoperative image sequences showing brain shift. The algorithm tracks key surfaces of objects (cortical surface and the lateral ventricles) in the image sequence using a deformable surface matching algorithm. The volumetric deformation field of the objects is then inferred from the displacements at the boundary surfaces using a linear elastic biomechanical finite-element model. Two experiments on synthetic image sequences are presented, as well as an initial experiment on intraoperative MR images showing brain shift. The results of the registration algorithm show a good correlation of the internal brain structures after deformation, and a good capability of measuring surface as well as subsurface shift. We measured distances between landmarks in the deformed initial image and the corresponding landmarks in the target scan. Cortical surface shifts of up to 10 mm and subsurface shifts of up to 6 mm were recovered with an accuracy of 1 mm or less and 3 mm or less respectively.     

The Application of Z-transform Techniques the Analysis of Paraxial Ray Propagation in Beam Waveguides

The Z-transform technique has been applied to the effect of lateral lens displacements on the propagation of paraxial rays in a lens guide. The Z transform of the ray displacement from the guide axis is obtained and techniques for obtaining the ray displacement from its Z transform are outlined. The property of the transform that determines the stability of the ray in the guide is given. To illustrate its use, the transform is used to obtain the response of the ray to the following types of lens displacements: 1) any arbitrary sequence of displacements, 2) sinusoidal lens displacements of arbitrary frequency, 3) sinusoidal lens displacements at the ray position resonant frequency, and 4) lens displacements that form a bend in the guide. Also an analogy is shown to exist between the response of linear circuits to amplitude modulated pulse trains, which is a function of time, and the response of the light ray to lateral lens displacements, which is a function of the distance of propagation down the guide.