突破衍射极限的成像方法综述（英文）

"衍射极限"实际上不是一个真正的障碍,除非处理远场和定位精度。这种衍射障碍并不是坚不可摧的,可以利用一些智能技术来突破光学衍射极限。讨论了四种技术,近场扫描光学显微镜(NSOM)法,受激发射损耗(STED)显微镜法,光激活定位显微镜(PALM)法或随机光学重建显微镜(STORM)法和结构照明显微镜(SIM)法,并且介绍了各自的基本原则与优劣。NSOM利用纳米级探测器检测通过光纤的极小汇聚光斑,从而获得单个像素的分辨率;PALM和STORM利用荧光探针,实现暗场和荧光的转换,从而观察到极小的荧光团;SIM则是利用栅格图案与样品叠加成像来实现。其中,STORM具有相对较高的潜力,能够更为有效地突破衍射极限。     

扫描近场光学显微镜

本文简介近场光学的基本原理一非辐射场的探测与高分辨率的关系；近场光学显微镜的仪器发展。同时简要介绍近场光学显微镜在超高分辨率光学成象，纳米尺度光学微加工与光刻，高密度磁光存储，近场光谱等领域中的应用。     

现代显微成像技术综述

概述了光学宽视场显微镜、共聚焦显微镜、超分辨率显微镜中所应用的现代显微成像技术,对各种传统和先进的显微成像原理进行了总结。光学宽视场显微镜最常用的显微技术有明场成像、暗场成像、相衬成像、偏光成像、微分干涉(DIC)成像、调制对比成像和荧光成像。相衬成像中根据不同的成像结构还有切趾相衬成像。微分干涉除了传统的偏振光照明还有圆偏振光照明(C-DIC)和专用于塑料的微分干涉(PlasDIC)。共聚焦显微镜随着计算机技术和制造技术的发展而有了巨大的发展。除了传统的共聚焦荧光显微镜以外,还有连续反斯托克斯拉曼散射(CARS)共聚焦、多光子共聚焦和白光共聚焦。超分辨率显微镜中主要介绍了受激辐射淬灭(STED)技术和紧随基态淬灭显微技术的单分子返回(GSDIM)技术。     

微光学系统矢量衍射成像中畸变的衍射机理与计算

用瑞利—索末菲矢量衍射公式导出微光学系统矢量衍射像点光强分布的计算式,探讨矢量衍射成像中畸变的衍射机理与计算。模拟试验表明微光学系统矢量衍射成像不但要考虑横向场还要考虑纵向场,畸变校正要进行位置校正,光强也要做适当校正,有利于微光学成像系统的像差分析与处理。     

一种基于无衍射光栅的三角测量的定标方法

基于光栅的三角测量方法是将光栅投射到被测物体表面,CCD接受由于物体表面高度起伏产生的变形光栅像,根据光栅变形量与高度的关系,恢复被测物体的三维形貌。提出了一种基于无衍射光栅的三角测量的定标方法。该方法通过空间坐标变换,方便地求出摄像机的内外参数,从而获得被测物体的三维信息。     

用于中红外成像的锗衍射光具

探测器技术的进展和信号处理在电子技术的改进 ,已使红外成像系统的重量和体积得到减轻和减小。可是 ,光具的尺寸和重量却并未因上述变化而得到相应的改变。为了进行追赶 ,光具设计人员已开始转向用衍射光具来取代传统的红外成像透镜。在过去的几年中 ,科学们曾经演示过用于 3μm～ 5μm近红外至中红外成像的硅衍射光具。现在 ,日本防卫厅的研究人员已演示了一种用于中红外的锗衍射光学元件。这种衍射透镜可以取代前视红外系统成像光具中的硒化锌消色差透镜。日本研究人员设计的这种衍射光学元件可将多元件系统成像透镜部件中的色差减小到最…     

显微红外光学成像系统的设计

红外热成像技术是现代影像学中的一门新兴技术。它与x射线、B超、CT、核磁共振等显像技术的成像原理不同,它不主动发射任何射线,只是被动接受热源所发射出的红外线,经过处理后得到热源的影像。该技术的最大特点是不用接触待测物体。因此,对于一些高危行业,如核工业中元器件的检测将变得非常容易。本文所叙述的就是利用红外热像技术与显微技术的结合,制作一种红外显微镜。红外显微镜可以将出现故障的大规模集成电路板中数以万计的微小元器件的影像传输到计算机中,经过计算机的分析,可以很容易地分析出具体故障所在。因此,大范同电子元器件故障的快速检测将变得简单、快捷。     

上海华建的极限突破

<正>2010年上半年,经过了金融危机的洗礼,上海华东建筑机械厂有限公司借助国家4万亿元投资机遇,迅速扭转不利局面,实现了以主导产品混凝土搅拌运输车为首的生产和销售量大突破。公司综合产值5.6亿元,同比增长75%;经营销售额5.8亿元,同比增长61.1%。     

近红外显微成像技术

以烟草混合样品为例简要介绍近红外显微成像技术和近红外显微镜的使用,介绍与之相关的实现化学成分鉴别的图像处理方法及图像显示方式。     

Progressive steps in the development of electron backscatter diffraction and orientation imaging microscopy

Ten years ago electron backscatter diffraction (EBSD) became available to a wider group active in materials research. This paper highlights some of the more significant developments in camera technology and software developments that have arisen since then. The use of slow‐scan charge couple device cameras for phase identification and rapid determination of orientation image micrographs is reviewed. The current limiting spatial resolution of the technique is shown to be less than 10 nm. A procedure for improving lattice spacing measurement by utilizing the full resolution of the camera is described with experimental measurements on silicon and nickel showing relative errors of plus/minus 3%. An investigation of partially recrystallized aluminium shows how the recrystallized fraction can be extracted with confidence but that the mapping of substructure in the highly deformed regions is questionable. Phase identification is described for complex cases in which the phase data tabulated in standard databases do not correspond to what is observed in the EBSD patterns. Phase mapping in a complex mineral in which chemical data and EBSD data are collected simultaneously is shown to be improved by recording both the chemical and the EBSD data into computer memory and proceeding with the phase discrimination and orientation measurement in off‐line analysis.     

用于微米球形颗粒超分辨尺度测量的背向弹性散射光谱的获取

背向弹性散射光谱法可用于研究生物细胞内部颗粒的结构组成,本文探讨了背向弹性散射光谱测量获取光谱的不同实验方法及其优缺点。针对微米量级的球形颗粒测量,基于实验分析比较了目前普遍使用的光纤探头测量和透镜系统测量这两种背向散射光谱获取方法的优缺点。研究表明,由于透镜系统获取光谱所对应的散射角有更明确的定义,故透镜系统获取光谱与Mie散射计算的互相关拟合系数(0.96)高于光纤探头优化条件下获取光谱的结果(0.93)。因此,在提取颗粒尺度精度要求较高时,应该选用透镜测量方法,并且采用滤波去噪声信号处理的手段来提高颗粒尺寸提取精度;而提取颗粒尺度精度要求不高时,光纤探头光谱获取方法具有简单易行的优点。     

Nanobeam electron diffraction and high resolution imaging analysis of InN films grown on sapphire

A JEOL JEM-3000F field emission, analytical, high-resolution transmission electron microscope (HRTEM) was used to study InN films grown on sapphire substrates. It was found that, while the InN films maintained the hexagonal (wurtzite) structure, InN nanodomains with a cubic (zincblende) structure were also formed in the films. Nanobeam electron diffraction techniques were applied for identification of the cubic phase. The identification of the cubic InN was confirmed by HRTEM structural imaging. The cubic InN nanodomains are 3-10 nm in diameter, and are orientated in two different orientations with their [110](cubic) and [110](cubic) axes parallel to each other and their (111)(cubic) planes parallel to the (0001)(hex) plane of the hexagonal InN.     

The scanning optical microscope (Extracts on near-field microscopy)—from a 1975 report

The following consists of extracts concerning near-field microscopy from a Progress Report prepared in April 1975 as Oxford University Engineering Laboratory Report No. 1883/77, describing work initiated by the late Professor R. Kompfner. Preliminary experimental work on near-field microscopy is outlined, and a theory for contrast formation is presented.     

The scanning optical microscope (extracts on near-field microscopy)—from a 1975 report

The following consists of extracts concerning near-field microscopy from a Progress Report prepared in April 1975 as Oxford University Engineering Laboratory Report No. 1883/77, describing work initiated by the late Professor R. Kompfner. Preliminary experimental work on near-field microscopy is outlined, and a theory for contrast formation is presented.     

Microscopy beyond the diffraction limit using actively controlled single molecules

In this short review, the general principles are described for obtaining microscopic images with resolution beyond the optical diffraction limit with single molecules. Although it has been known for several decades that single-molecule emitters can blink or turn on and off, in recent work the addition of on/off control of molecular emission to maintain concentrations at very low levels in each imaging frame combined with sequential imaging of sparse subsets has enabled the reconstruction of images with resolution far below the optical diffraction limit. Single-molecule active control microscopy provides a powerful window into information about nanoscale structures that was previously unavailable.     

Exploring the precision of backlight optical imaging in microfluidics close to the diffraction limit

We evaluate the precision of backlight optical imaging to locate the position of a free surface close to the diffraction limit. For this purpose, we acquired and processed images of liquid films at equilibrium deposited on a capillary 10 μm in diameter. The detected contours were compared with the solution of the exact Young-Laplace equation. Deviations of about 10 nm were obtained, which constitutes the first quantitative validation of backlight optical imaging for fluid shapes a few microns in size. The local mean curvature measured in the experiments agreed remarkably with the theoretical values. We illustrate the applicability of this technique by analysing five interfacial phenomena: (i) the flow in the tip of a capillary tapering meniscus formed by flow focusing, (ii) the extensional deformation of viscous micro-jets by the action of a co-flowing gas stream, (iii) the growth of small-amplitude capillary waves on a micro-jet free surface, (iv) the flow in the tip of a capillary tapering meniscus produced by electrospray, and (v) the characterization of glass micro-nozzles.     

Far field resolution beyond the Abbe limit using photodiffraction

In this paper we show how a tightly focused pump beam can be used to alter the local refractive index of the sample. This local variation acts as a scattering site, which enables resolution exceeding that of a conventional scanning microscope to be obtained in the far field. The improvement in resolution depends on a number of factors which are discussed in the paper, including the optical configuration (confocal or non-confocal), the thermal properties of the sample, the 'strength' of the object and the duration of the heating pulse. Experimental results confirming the theoretical predictions are presented; these demonstrate more than 25% improvement in edge response compared with a conventional scanning system.     

Application of electron backscatter diffraction to the study of phase transformations: present and possible future

This paper first underlines the main advantages, use and limitations of the electron backscatter diffraction technique from the viewpoint of phase transformations. To get a deeper understanding of physical mechanisms involved in phase transformations, several evolutions are now in progress to get an insight into both three-dimensional and real-time information. Two of them, in particular, improvement of data collection versus improvement of data processing are discussed in the second part of this paper.