电容成像技术及其应用

过程成像技术是近十多年来发展起来的一种新型过程检测技术，可以广泛应用于石油、化工、电力及冶金等行业中的两相流测量。本文结合清华大学自动化系过程成像小组研制的电容成像系统，介绍了电容成像技术的发展和现状，包括电容成像基本原理、微电容测量电路和图像重建算法等。论文给出了现有系统在小型流化床模拟装置上进行测量和连续图像重建的实验结果，并进行了分析。此外，论义对电容成像技术今后的发展作出了展望。     

显微热成像系统行处理迭代超分辨力处理研究

针对已研制光学微扫描显微热成像系统空间分辨力较低的问题,基于改进的频域图像配准技术和改进的行处理迭代超分辨力算法,提出了显微热成像系统光学微扫描改进行处理迭代超分辨力图像处理方法。给出了该方法的原理及步骤,采用不同重构方法针对可见光和红外图像进行了仿真研究,给出了评价参数和结论。利用光学微扫描显微热成像系统采集低分辨力显微热图像序列进行了超分辨力处理实验,实验结果表明本文提出方法的有效性,光学微扫描显微热成像系统的空间分辨力得到提高,可应用于需要显微热分析的场合。该方法还可以应用于其它不可控光学微扫描成像系统中,具有广泛的应用前景。     

新型计算成像技术——波阵面编码

波阵面编码成像（WFC）技术使用特殊光学表面一立方相位屏（CPM）一以编码的形式捕捉图像；这些由光学系统捕捉的“信息”经由后续的数字处理得到最终的图像。它能够大幅度地提高成像系统的性能并或减少成本。波阵面编码成像系统的设计技术与传统成像系统相比是独特的。这是因为，为使系统性能达到最优，必须对系统的光学与数字处理特性进行共同优化。本文针对波阵面编码成像系统的背景、技术特点、优点、设计和应用进行了简要讨论。     

JJF1530-2015《凝胶成像系统校准规范》解读

<正>凝胶成像系统是一种成像装置,可将采集的图像通过相应的分析软件,进行定性和辅助定量分析。目前,普遍应用于分子生物学研究和医院临床检验。随着科学技术的不断发展,凝胶成像系统衍生出的种类也越来越多,由最初可对经染料染色的电泳凝胶样品进行图像采集的普通凝胶成像系统,到成像范围涵盖紫外激发、化学发光、多色荧光、离体组织和小型、大型动物的多用途成像分析系统。其应用范围也越来越     

高速窄带多光谱成像系统光谱重建技术研究

光谱成像技术可以同时从光谱维和空间维上获取被测目标的信息，即结合了空间成像系统和光谱检测系统的功能，因此近年在影像获取与处理领域中倍受重视。本论文基于窄带多光谱成像技术建立八通道CCD多光谱成像系统，它能够实时采集八个通道的图像，获得波长分布从可见到红外（420-940nm）八个波段的光谱响应值。在此基础上对图像进行位置配准、反射率定标、采用插值算法获得其它波段光谱响应值，最终能够获取图像中任意一点的光谱反射率及颜色参数。实验结果表明，本文使用的三次样条插值法对原始光谱图像进行平滑操作的方法是有效的，能够以一定精度模拟出目标物点的真实光谱特性。该系统在动态目标检测识别、艺术品评价复制等领域有着广阔的应用前景。     

排序滤波在工业射线图像系统中的应用

本文通过对工业射线成像系统的分析，比较了射线噪声图像的两种处理方法－线性滤波法和排序滤波法，实验表明，排序滤波地能够在减少白噪声的同时保存图像细节，是射线检测中一种有效的降噪增强处理方法。     

高速高分辨率CMOS图像采集系统设计与实现

本文介绍了一种高速高分辨率CMOS图像采集系统。给出了系统结构原理,分析了CMOS图像传感器驱动时序,研制了系统成像与高速图像数据存储电路。设计了系统数据采集和应用软件。系统全帧图像读出帧频率最高可达500帧/秒,图像分辨率为1280×1024,曝光时间最快10μs。     

SRR在多线阵错位排列扫描系统中的实现

为了获得尽可能高的空间分辨率的图像,超分辨率重构技术(SRR)成为了红外扫描成像的研究热点.本文以红外多线阵错位排列扫描成像系统为研究平台,通过分析SRR实现过程及待重构图像获取的方式,分析了红外多线阵错位排列扫描成像系统中SRR有效的关键.实验表明:对于固定错位量的多排传感器扫描成像系统,影响重构图像质量的主要因素是各通道所获得的待重构图像同位像素灰度不一致引入的噪声.本文提出的基于序列逐像素比较滤波法,可以大大提高重构图像质量.     

军用CCD图像传感器的新发展

概述了军用成像系统中，国内外ＣＣＤ图像传感器的新发展。     

聚合物光纤几何参数测量系统

基于CCD图像技术提出了显微放大成像、图像相对测量，通过计算机图像处理完成外径的为1mm聚合物光纤几何参数（芯径、外径、不圆度）的测量，测量精度为6μm左右。并给出了系统的结构与原理，分析了系统实现的精度保证。该系统也可实现聚合物光纤数值孔径的测量和折射率分布的表征等。     

Label‐Free Optofluidic Nanobiosensor Enables Real‐Time Analysis of Single‐Cell Cytokine Secretion

Single‐cell analysis of cytokine secretion is essential to understand the heterogeneity of cellular functionalities and develop novel therapies for multiple diseases. Unraveling the dynamic secretion process at single‐cell resolution reveals the real‐time functional status of individual cells. Fluorescent and colorimetric‐based methodologies require tedious molecular labeling that brings inevitable interferences with cell integrity and compromises the temporal resolution. An innovative label‐free optofluidic nanoplasmonic biosensor is introduced for single‐cell analysis in real time. The nanobiosensor incorporates a novel design of a multifunctional microfluidic system with small volume microchamber and regulation channels for reliable monitoring of cytokine secretion from individual cells for hours. Different interleukin‐2 secretion profiles are detected and distinguished from single lymphoma cells. The sensor configuration combined with optical spectroscopic imaging further allows us to determine the spatial single‐cell secretion fingerprints in real time. This new biosensor system is anticipated to be a powerful tool to characterize single‐cell signaling for basic and clinical research.     

基于运动补偿的机械扫描式高频超声成像技术

由于高频相控阵超声成像系统和多阵元高频超声探头工艺复杂,成本较高、实现难度大,单阵元的机械扫描式高频超声成像探头因其结构简单、实现方便、成本低的特点仍具有较高的理论研究和实际应用价值。但目前机械扫描式成像系统的机械扫描的非均匀性是阻碍其性能进一步提升的主要问题,因此文章设计了一种高精度运动补偿的机械扫描式高频超声成像探头和系统,通过理论计算分析、运动系统结构设计加工、扫描成像系统搭建实现了高精度的扫描成像。最后,线靶和仿体的成像实验结果显示,经运动补偿后,系统能够有效克服传统机械扫描成像的伪影和失真,实现的横向几何位置精度误差为1.34%,纵向几何位置精度误差为1.33%,面积测量精度误差为3.15%,为高精度、高频超声成像算法和系统研究提供了一种有效的手段。     

Shannon number and information capacity of three-dimensional integral imaging

Integral imaging systems performance has been previously investigated with regard to different parameters such as lateral resolution, field of view, and depth of view. Those parameters are linked to one another, and, since the information capacity of an integral imaging system is finite, there are always trade-offs among them. We use the Shannon number and information capacity limit as figures of merit of integral imaging systems. The Shannon number and information capacity provide compact assessments of the system and are useful for analysis and design. The limitations on the Shannon number and the information capacity of an integral imaging system are determined by the recording and display media.     

中波红外全景成像仪线扩散函数的模拟分析与验证

线扩散函数是评价成像系统成像质量的一个重要参数,线扩散函数的模拟分析与验证对成像仪的研制至关重要。本文首先分析中波红外全景成像仪探测器所接收到的辐亮度,从理论上估算了全景成像仪的线扩散函数,然后通过斜缝法加以验证,试验结果证实了理论模型的正确性。并对线扩散函数经离散傅里叶变换计算而得MTF传递函数,结果与理论得出的系统MTF基本符合,进一步证明了这种模拟分析方法的可行性。     

像元间隔对亚像元动态成像系统MTF的影响

亚像元动态成像系统的调制传递函数MTF主要取决于像元尺寸及像元间隔等因素的影响。分析了像元间隔对亚像元动态成像系统的调制传递函数的影响，并给出了数值分析的结果：像元间的隔对亚像元动态成像系统MTF的影响总的趋势是随着像元间的增大而增大。     

Signal-to-noise analysis of task-based imaging systems with defocus

We analyze the signal-to-noise ratio (SNR) of arbitrary imaging systems in the presence of defocus. The modulation transfer function (MTF) and the mean SNR are combined to calculate the spatial-frequency spectrum of the SNR (the spectral SNR). Computational imaging methods are used for extending the depth of field (DOF) of the system. The DOF of a task-specific imaging system is defined as the range of defocus that causes the spectral SNR to drop below a minimum value within a band of spatial frequencies of interest. We introduce the polar-SNR plot as a tool for visualizing the spectral SNR of defocused imaging systems with asymmetric pupil functions. As an example, we perform the analysis of an imaging system used for biometric iris recognition.     

Design and Characterization of an AOTF Hyper-Spectral Polarization Imaging System

The present paper describes a hyper-spectral polarization imaging system based on a non-collinear, acousto-optic tunable filter (AOTF) and a linear polarizer. The paper begins with an analysis of the equivalent relationship of the AOTF to describe the principle of polarization detection of this system. Appropriate parameters of hardware components are assigned later. This system, being electronically controllable and tunable, can not only ensure the precision of imaging but also obtain hyper-spectral polarization signatures. The prototype has two optional working modes, namely, hyper-spectral polarization imaging and hyper-spectral intensity imaging. Moreover, parameters of this system – such as diffraction efficiency, spectral resolution and modulation precision – are tested using a halogen tungsten lamp and an optical fibre spectrometer. The results indicate that this instrument is compact, vibration-insensitive, robust and precisely controllable. The system designed in this paper has further application in polarization detection techniques in military.     

Acousto-optic tunable filter imaging spectrometer with full Stokes polarimetric capability

Polarization is an important addition to spectral imaging in detecting and identifying objects of interest, and simple linear polarization measurements are often inadequate. Full polarization analysis can give additional information for discrimination where the polarization state is completely described by the Stokes parameters. An acousto-optic tunable filter (AOTF) imaging system was built incorporating two liquid-crystal variable retarders (LCVRs) that can provide complete spectral-polarimetric analysis, and it is believed to be the first demonstration of a full Stokes polarimetric AOTF spectral imaging system with no moving parts. It is also shown that a single LCVR cannot provide all the Stokes parameters.     

Disentangling dynamic changes of multiple cellular components during the yeast cell cycle by in vivo multivariate Raman imaging

Cellular processes are intrinsically complex and dynamic, in which a myriad of cellular components including nucleic acids, proteins, membranes, and organelles are involved and undergo spatiotemporal changes. Label-free Raman imaging has proven powerful for studying such dynamic behaviors in vivo and at the molecular level. To construct Raman images, univariate data analysis has been commonly employed, but it cannot be free from uncertainties due to severely overlapped spectral information. Here, we demonstrate multivariate curve resolution analysis for time-lapse Raman imaging of a single dividing yeast cell. A four-dimensional (spectral variable, spatial positions in the two-dimensional image plane, and time sequence) Raman data "hypercube" is unfolded to a two-way array and then analyzed globally using multivariate curve resolution. The multivariate Raman imaging thus accomplished successfully disentangles dynamic changes of both concentrations and distributions of major cellular components (lipids, proteins, and polysaccharides) during the cell cycle of the yeast cell. The results show a drastic decrease in the amount of lipids by ~50% after cell division and uncover a protein-associated component that has not been detected with previous univariate approaches.     

Quantum dots with phenylboronic acid tags for specific labeling of sialic acids on living cells

Sialic acids with a nine-carbon backbone are commonly found at the terminal position of the glycans structures on cell membranes. The unique distribution and ubiquitous existence of sialic acid on the cell membrane make them important mediators in various biological and pathological processes. We report a new class of imaging probes based on semiconductor quantum dots with small molecular phenylboronic acid tags for highly specific and efficient labeling of sialic acid on living cells. Our results have shown that the use of these probes enables one-step labeling and continuous tracking of the cell surface sialic acid moieties without any pretreatment of living cells. The one-step procedure with fast binding kinetics and the biocompatibility of these probes make it an ideal noninvasive technology for living cell imaging. We also find that the labeled sialic acids undergo quick internalization shortly after surface binding via endocytosis and eventually distribute in the perinuclear region. This distribution pattern is consistent with the notion that sialylated glycoproteins are populated on cell membranes and recycled through the vesicular exocytotic and endocytic pathways. The superior photostability and brightness of quantum dots enable quantitative analysis of the diffusion dynamics of sialic acids, which has been a significant challenge for glycan imaging.