共查询到19条相似文献,搜索用时 78 毫秒
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正入射多层膜软X射线显微成像系统的实验研究王占山,曹健林,马月英,陈星旦(中国科学院长春光学精密机械研究所应用光学国家重点实验室长春130022)0引言在过去的软X射线显微成像系统研究中,绝大部分是以同步辐射做光源的。但由于同步辐射光源造价昂贵,机时... 相似文献
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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。 相似文献
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围绕着八通道Kirkpatrick-Baez(KB)显微镜在神光-Ⅲ主机上的应用,分析了瞄准误差对该显微镜成像性能和通道间一致性的影响。通过光线追迹,模拟了X射线显微镜的空间分辨率、像点间隔和系统效率随视场和物像距的变化。从中心视场到±200μm视场,空间分辨率下降约2.9μm;从中心视场到±150μm视场,系统效率降低了约60%;物距变化量在±200μm范围时,像点间隔变化值约为0.67 mm,显微镜系统效率变化约为7%;像距变化量在±20mm范围时,像点间隔变化值约为0.70 mm。结果表明,视场中心瞄准误差严重影响空间分辨率和效率,但对各通道间的像间隔影响较小。物距和像距误差对像间隔影响较大,但对空间分辨率和系统效率影响较小。 相似文献
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研制了光发射电子显微镜(PEEM)高精度微聚焦系统,以实现上海光源软X射线PEEM光束线的高质量聚焦。根据上海光源PEEM光束线的概况,给出微聚焦系统光学元件的基本参数。基于Kirkpatrick-Baez(KB镜)两镜方案,设计了PEEM线微聚焦系统。介绍了KB镜姿态调整机构的设计方案,即利用三垂直线性驱动装置和两水平线性驱动装置相结合来实现五维调节,分析了姿态调节机构的原理与工作过程,给出了微聚焦系统的整体设计方案。测试了KB镜系统的机械性能,给出水平调节机构以及第一面镜子Pitch运动的测试结果,结果显示:水平调节机构分辨率为0.6μm,重复精度为0.85μm,Pitch角度分辨率为0.4″,重复精度为0.5″,优于指标要求。其它参数的测试结果亦均优于指标要求。实验表明,微聚焦系统机械指标的实现保证了PEEM线光斑的高质量聚焦。 相似文献
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Improved longitudinal resolution in tomographic diffractive microscopy with an ellipsoidal mirror 下载免费PDF全文
Tomographic diffractive microscopy is a technique, which is able to image transparent unstained samples with high resolution. The three‐dimensional distribution of the complex refractive index can be reconstructed quantitatively from the measured scattered fields under various illumination and detection angles, according to the diffraction tomography theorem. We propose a tomographic diffractive microscopy setup with an ellipsoidal mirror as the light collector. We demonstrate analytically and with numerical simulation that this approach permits to obtain images with drastically improved resolution. 相似文献
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The two conventional methods currently employed for the evaluation of image resolution in scanning electron microscopy are the gap method and a fast Fourier transform (FFT) method. These can be highly dependent on personal expertise on the distinction between signal information and noise contained in a micrograph. Hence, the present paper proposes an alternative method (referred to as a contrast-to-gradient (CG) method) that can determine the image resolution of a micrograph without requiring personal expertise on the judgment of noise. The image resolution in the CG method is defined as a weighted harmonic mean of the local resolution, which is proportional to the quotient of the threshold contrast divided by the local gradient. The local gradient is calculated from the quadratic function that best fits the local pixel intensities over 5 x 5 pixels. It has been shown that the CG method, compared with the FFT method, has a broader range of applications for various types of images, such as low-contrast, noise-containing, filter-processed, highly directional, and quasi-periodic feature images. 相似文献
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C. J. R. Sheppard 《Journal of microscopy》1989,154(3):237-241
A simple analytic expression is given for the axial resolution of a confocal fluorescence microscope. The expression, which is based on the spatial frequency cut-off criterion of resolution, is valid for high aperture optics and arbitrary fluorescence wavelength. 相似文献
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以同心多尺度成像模式为基础,结合人眼视网膜凹成像思想,提出了一种宽视场与双分辨率成像组合的新型同心多尺度成像系统,在广域视场范围内实现了对关注的感兴趣目标区域的高分辨动态注视。介绍了同心多尺度双分辨率成像系统的工作方式;使用一个单透镜和一个双胶合透镜为初始结构,结合二轴微机电系统(MEMS)扫描微镜组合形成光路;利用ZEMAX光学设计软件,优化设计了成像波段为0.486~0.656μm,在单个分通道视场内(30°)可对关注的小视场区域(6°)高分辨注视跟踪的子成像系统。对成像系统的像质以及点列图、调制传递函数(MTF)曲线、场曲、畸变曲线进行了评价。结果表明设计的子成像系统在全视场内成像均匀,接近衍射极限,场曲和畸变较小,最大场曲不超过0.6mm,最大畸变小于1.5%,能够满足同心多尺度双分辨率成像系统对子成像系统性能的要求。 相似文献
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We consider the case of soft X-ray contact microscopy using a laser-produced plasma. We model the effects of sample and resist absorption and diffraction as well as the process of isotropic development of the photoresist. Our results indicate that the micrograph resolution depends heavily on the exposure and the sample-to-resist distance. In addition, the contrast of small features depends crucially on the development procedure to the point where information on such features may be destroyed by excessive development. These issues must be kept in mind when interpreting contact microradiographs of high resolution, low contrast objects such as biological structures. 相似文献
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The authors present the experimental result of improved lateral resolution in laser confocal microscopy (LCM) by using annular and radially polarized light as the input illumination of an existing LCM. The authors examined the lateral resolution of the LCM by imaging a single fluorescent bead and measuring the lateral width of the single bead profile appearing in the optical image. Compared to no aperture and linearly polarized light, the central peak of the single bead profile narrowed by ∼40%, being as small as 122 nm in full width at half maximum using 405 nm laser excitation in a reflection imaging. In addition, the authors showed that radial polarization helps to preserve the circular shape of the single bead profile whereas linearly polarized light tends to induce an elongation along the polarization direction. Microsc. Res. Tech., 2009. © 2009 Wiley-Liss, Inc. 相似文献
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The protein organization within focal adhesions has been studied by state‐of‐the‐art super resolution methods because of its thin structure, well below diffraction limit. However, to achieve high axial resolution, most of the current approaches rely on either sophisticated optics or diligent sample preparation, limiting their application. In this report we present a phasor‐based method that can be applied to fluorescent samples to determine the precise axial position of proteins using a conventional confocal microscope. We demonstrate that with about 4,000 photon counts collected along a z‐scan, axial localization precision close to 10 nm is achievable. We show that, with within 10 nm, the axial location of paxillin, FAK, and talin is similar at focal adhesion sites, while F‐actin shows a sharp increase in height towards the cell center. We further demonstrated the live imaging capability of this method. With the advantage of simple data acquisition and no special instrument requirement, this approach could have wide dissemination and application potentials. Microsc. Res. Tech., 76:1070–1078, 2013. © 2013 Wiley Periodicals, Inc. 相似文献