投影散斑相关方法测量芯片翘曲度

本文采用投影散斑相关法对芯片翘曲度进行了测量。利用单个CCD和单个投影装置多次扫描的方法，得到若干幅具有部分重叠区域的小图像，然后通过配准和拼接获得全景图像，实现整体测量。在拼接区标定若干控制点，然后以这些控制点为基准进行坐标变换实现重叠区域的配准和拼接，以提高分辨率、实现全场测量，得到芯片相对于标准平面的面内位移和形变。通过三角法标定，获得了离面位移和形变，从而完成了对手机屏幕芯片翘曲度的测量。与牛顿环测量法相比较，结果证明了投影散班方法测量芯片翘曲度的精度和可行性。     

面投影微立体光刻系统的开发和研究

面投影微立体光刻由于具有加工精确度高、分辨率高、速度快等特点而成为最有前途的微立体加工技术之一。本文介绍了实验室开发的用于复杂器件制作的面投影微立体光刻系统,该系统中采用LED模组作为光源,为了适用粘度大的固化材料的加工,设计新的树脂槽和涂覆系统。对系统中使用的投影镜头的光学分辨率以及树脂的工作曲线进行了测量,系统的加工横线分辨率可以达到14μm。利用该系统成功制作了齿轮的模型。     

发展中的数字投影技术

本文阐述了数字影像输出的第一大类领域；数字投影技术。数字投影技术属于数字图像输出软拷贝范畴。数字投影以数字投影机为典型产业技术，包括显像管CRT，液晶LCD和数字光处理器DLP技术等，最后阐述了GLV和DLV两种未来投影技术。     

快速离焦投影三维测量技术

随着数字投影技术的发展,基于投影的三维面型测量技术在多种场合得到广泛应用。基于相移的结构光投影测量技术以其算法简便精度较高得到较快发展。但投影仪为非线性仪器,会影响强度变化,进而影响相位测量精度;此外由于投影仪工作原理的投影速度受到限制。离焦投影技术的出现为高速测量和高精度测量提供了新的方法。总结了目前国内外对离焦投影技术的研究现状;从投影工作原理、相移算法、解包裹算法、误差补偿、条纹调制、标定技术及离焦投影技术的相关技术细节进行全面介绍,为数字离焦投影三维测量工作的研究提供参考。     

软X射线投影光刻原理装置的设计

首先介绍了投影光刻技术发展的历程、趋势和软X射线投影光刻技术的特性,其次介绍了软X射线投影光刻原理装置的研制工作.该装置由激光等离子体光源、掠入射椭球聚光镜、透射掩模、镀有多层膜的Schwarzchild微缩投影物镜、涂有光刻胶的硅片及相应的真空系统组成.0.1倍的Schwarzchild微缩投影物镜具有小于0.2μm的分辨率.     

基于光栅相位法三维重构技术研究

投影光栅相位法（PMP）是一种基于光栅投影和相位测量的光学三维轮廓测量技术,可实现物体表面三维轮廓的自动测量。提出了结合投影仪移轴技术的平行光轴系统,利用计算机编程生成具有高对比度和高亮度、有相差的正弦光栅,用数字投影仪LCD将这些条纹依次投射到被测物体表面,由CCD摄像机获取受物体表面面形调制的变形光栅像,根据数字相移算法计算出相位分布再通过相位展开恢复出连续相位分布,由相位．高度关系最终求出物体轮廓的三维数据信息。针对该原理进行了阐述,并给出了详尽的算法及实验结果。通过MATLAB实验仿真,对条纹图像进行处理和轮廓重构。模拟实验证明,这种测量方法快速高效、分辨率高,且易于实现。     

基于图像拼接的尺寸精密检测算法研究

针对基于机器视觉的大长径比类零件几何尺寸综合检测中因要求视场大而导致分辨率低,投影误差大等问题,将图像拼接技术应用到视觉测量中,采用已标定摄像机方式建立图像投影模型、提出了基于位姿变换的图像拼接算法实现图像之间的精确配准、基于最佳阈值灰度调整的图像融合以消除图像拼接接缝.通过对标准模板进行检测实验,测量精度可达到±0.006mm,重复测量精度≤0.004mm,结果证明了该算法的可行性.     

投影法CCD测径系统

文中介绍以线阵CCD作为光电传感器的投影放大法线径测量系统,着重分析提高系统稳定性和测量精度的方法。系统以半导体激光器为光源,成像系统采用物方远心光路。对阴影图像进行一阶微分并求其局部重心点作为其边缘特征点。对光学系统放大倍数和成像系统像差分别进行线性、非线性标定以提高测量精度。     

投影管真空冷液灌装系统的设计

介绍了投影管真空冷液灌装系统的工艺流程,分析了具体的实现方式,并提出了几种设计方案,在方案比较的基础上确定了最终方案,然后对系统设计的主要部分进行了详细说明。     

基于二次投影法的偏心轴检测与分析

为了提高偏心轴的测量精度,提出采用二次投影法对偏心轴进行检测与分析。分析了二次投影法的测量原理。通过采用光学影像测量机对偏心轴进行二次投影测量,得到偏心轴在相互垂直的两个平面上的投影数据;对投影数据进行处理,得到偏心轴各轴段中心线端点在空间坐标系中的坐标值,从而进一步建立起各个轴段中心线在空间中的真实矢量。根据得到的矢量数据可以提取出对偏心轴结构进行分析所需的各种参数,从而能够对偏心轴的偏心距和同轴度等加工质量进行合理分析。研究表明,采用二次投影法可以大幅度提高偏心轴的测量精度。     

基于图像反卷积的平板探测器信号串扰校正

平板探测器是锥束CT的关键组成部件，像元间的信号串扰是造成平板探测器投影图像空间分辨率低于极限值的主要因素，校正平板探测器信号串扰对提高锥束CT检测精度具有重要意义。本文基于点扩散函数矩阵反卷积投影图像去串扰校正思路，研究了点扩散函数矩阵的准确性对投影图像串扰校正的影响、点扩散函数和线扩散函数的关系及其与X射线成像的相似性，提出一种结合刀口法测量线扩散函数与平行束CT扫描重建的平板探测器点扩散函数矩阵测算方法。DR/CT扫描成像实验中，应用本文方法校正信号串扰后，DR成像空间分辨率由约10 lp/mm提升至优于25 lp/mm,高能CT成像空间分辨率由不到4 lp/mm提升至优于5 lp/mm,实验证明，应用本文方法能有效校正平板探测器信号串扰，提升锥束CT图像的空间分辨率和对比度。     

100-ps framing-camera tube

The optoelectronic framing-camera tube described is capable of recording two-dimensional image frames with high spatial resolution in the <100-ps range. Framing is performed by streaking a two-dimensional electron image across narrow slits. The resulting dissected electron line images from the slits are restored into framed images by a restorer deflector operating synchronously with the dissector deflector. The number of framed images on the tube's viewing screen equals the number of dissecting slits in the tube. Performance has been demonstrated in a prototype tube by recording 135-ps-duration framed images of 2.5-mm patterns at the cathode. The limitation in the framing speed is in the external drivers for the deflectors and not in the tube design characteristics. Faster frame speeds in the <100-ps range can be obtained by use of faster deflection drivers.     

Efficient texture analysis of binary images

A new method of determining some characteristics of binary images is proposed based on a special linear filtering. This technique enables estimation of the area fraction, the specific line length and the specific integral of curvature. Furthermore, the specific length of the total projection is obtained, which gives detailed information about the texture of the image. The influence of lateral and directional resolution depending on the size of the applied filter mask is discussed in detail. The technique includes a method of increasing directional resolution for texture analysis while keeping lateral resolution as high as possible.     

Towards 1.0 Å resolution: taking advantage of dynamical scattering, and the benefits for structure retrieval

This paper is an exploration of the behaviour of high-resolution transmission electron microscope (HRTEM) images at up to 1 Å resolution. The ultimate limits to HRTEM (structure) resolution and the manner in which strong scattering may lead to weak diffraction in heavy fcc metals are discussed. A resolution of 1.0 Å is somewhat better than the ultimate resolution presently achievable in a 400-kV electron microscope. In heavy metals, such as platinum, it is found that the lattice fringe contrast is very low in the [011] projection, but that fringe contrast may be improved by imaging in the [111] projection. For atomic resolution imaging of the heavy metals in the [111] projection a resolution of 1.2 Å is required. For the study of oxygen position in high-temperature superconducting (HTS) oxides a resolution of between 1.2 and 1.4 Å is required. At better than 1.2 Å resolution the thick crystal images in HTS oxides remain simple and are easily interpreted. At such resolution all atomic columns are separated for the HTS [010] projection and the dynamical diffraction effects improve the contrast of oxygen atoms relative to the metal atoms.     

Compact x-ray microtomography system for element mapping and absorption imaging

We have designed and built a compact x-ray microtomography system to perform element mapping and absorption imaging by exploiting scanning fluorescence tomography and full-field transmission microtomography, respectively. It is based on a low power microfocus tube and is potentially appropriate for x-ray diagnostics in space. Full-field transmission tomography yields the three-dimensional inner structure of an object. Fluorescence microtomography provides the element distribution on a virtual section through the sample. Both techniques can be combined for appropriate samples. Microradiography as well as fluorescence mapping are also possible. For fluorescence microtomography a small and intensive microbeam is required. It is generated using a polycapillary optic. Operating the microfocus tube with a molybdenum target at 12 W, a microbeam with a full width at half maximum lateral extension of 16 microm and a flux of about 10(8) photonss is generated. As an example of application, this beam is used to determine the element distribution inside dried plant samples. For full-field scanning tomography, the x-ray optic is removed and the sample is imaged in magnifying projection onto a two-dimensional position sensitive detector. Depending on the sample size, a spatial resolution down to about 10 microm is possible in this mode. The method is demonstrated by three-dimensional imaging of a rat humerus.     

工业CT图像环形伪影校正

为了去除工业CT图像中的环形伪影,提高CT重建图像质量以及后续处理和量化分析的精度,提出了一种基于投影正弦图的新型校正方法。首先,采用S-L滤波器对原始投影数据进行滤波,增强伪影信息。接着,对滤波后的投影数据进行线积分,并采用差分处理,进一步增大伪影与工件轮廓的差异。然后,按照插值次数对差分后的投影数据进行插值平均,并根据正态分布选取自动查找伪影的位置。最后,结合线性插值与线性外推的方法对环形伪影处投影数据进行校正。对含有环形伪影的实际CT图像进行了校正实验,结果表明,与基于极坐标变换、小波-FFT滤波的校正方法相比,该方法校正后的灰度图像信噪比增益达1.688 dB,有效地消除了环形伪影,同时又很好地保持了图像边缘及分辨率。对探测器故障或性能不稳定引起的间断的环形伪影校正效果良好。     

一种新的计算机层析方法研究

提出了基于有限元的层析图像重建技术,该方法使用单元顶点上的目标值计算信号投影,详细推导了信号衰减也即目标物理量在检测线上的投影与单元节点值的关系,同时推导了单元刚度阵的计算公式,并提出了整体刚度阵、方程右边常向量的计算方法。最后还使用此方法对一仿真检测结果进行了重建分析,从分析结果来看,因此方法得到的系数矩阵对称正定,可以用ICCG等大型稀疏方程组求解方法求解,图像重建过程较经典ART方法效率更高,精度也更高。     

High-intensity xenon plasma discharge lamp for bulk-sensitive high-resolution photoemission spectroscopy

We have developed a highly brilliant xenon (Xe) discharge lamp operated by microwave-induced electron cyclotron resonance (ECR) for ultrahigh-resolution bulk-sensitive photoemission spectroscopy (PES). We observed at least eight strong radiation lines from neutral or singly ionized Xe atoms in the energy region of 8.4-10.7 eV. The photon flux of the strongest Xe I resonance line at 8.437 eV is comparable to that of the He Ialpha line (21.218 eV) from the He-ECR discharge lamp. Stable operation for more than 300 h is achieved by efficient air-cooling of a ceramic tube in the resonance cavity. The high bulk sensitivity and high-energy resolution of PES using the Xe lines are demonstrated for some typical materials.     

常用代数曲面求交新算法

提出了一种新的基于“结式法”的常用代数曲面求交算法,该算法首先利用结式法计算出两个曲面相交时交线的投影方程,再对投影方程进行分解等处理。通过循环计算从而得到投影交线的分支数及一系列的点,然后再代入相交的二次曲面方程即可得到两曲面的交线。该算法实现简单且符合求交算法的稳定、准确和快速等要求。     

三辊抱芯机构数学模型的建立

三辊抱芯机构是无缝钢管生产线上的重要设备之一,其控制精度对钢管质量有直接的影响。对三辊抱芯机构进行了结构性分析,并建立了数学模型。