Practical factors affecting the performance of a thin-film phase plate for transmission electron microscopy.
Practical factors affecting the performance of a thin-film phase plate for transmission electron microscopy.
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DOI：
10.1016/j.ultramic.2008.12.006
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发表时间：
2009-03
期刊：
影响因子：
2.2
通讯作者：
Nagayama, Kuniaki
中科院分区：
文献类型：
--
作者：
Danev, Radostin;Glaeser, Robert M.;Nagayama, Kuniaki
当使用薄碳膜作为Zernike相衬电子显微镜的四分之一波片时，必须解决一些实际问题。我们描述，例如，我们如何满足更严格的要求，必须满足在这种成像模式下的光束对准。此外，我们解决的问题，人们可能有关于一些散射电子的损失，因为他们通过这样的相位板。我们表明，两个容易测量的参数，（1）低分辨率的图像对比度产生的冷冻EM图像的烟草花叶病毒颗粒和（2）在高分辨率的包络函数的下降，可以用来定量比较Zernike相衬图像和散焦亮场图像的数据质量。我们描述了我们如何准备碳膜相位板，最初是免费的充电或其他影响，降低图像质量。然而，我们强调，即使可以通过在使用期间加热相位板来避免碳氢化合物污染物的积累，但是它们的性能在几天到几周的时间尺度内仍然会恶化，因此需要频繁更换它们以保持最佳性能。
A number of practical issues must be addressed when using thin carbon films as quarter-wave plates for Zernike phase-contrast electron microscopy. We describe, for example, how we meet the more stringent requirements that must be satisfied for beam alignment in this imaging mode. In addition we address the concern that one might have regarding the loss of some of the scattered electrons as they pass through such a phase plate. We show that two easily measured parameters, (1) the low-resolution image contrast produced in cryo-EM images of tobacco mosaic virus particles and (2) the fall-off of the envelope function at high resolution, can be used to quantitatively compare the data quality for Zernike phase-contrast images and for defocused bright-field images. We describe how we prepare carbon-film phase plates that are initially free of charging or other effects that degrade image quality. We emphasize, however, that even though the buildup of hydrocarbon contamination can be avoided by heating the phase plates during use, their performance nevertheless deteriorates over the time scale of days to weeks, thus requiring their frequent replacement in order to maintain optimal performance.
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影响因子：
3
作者：
Danev, Radostin;Nagayama, Kuniaki
通讯作者：
Nagayama, Kuniaki
影响因子：
2.8
作者：
Glaeser, RM;Downing, KH
通讯作者：
Downing, KH
影响因子：
1.8
作者：
Danev, R;Okawara, H;Nagayama, K
通讯作者：
Nagayama, K
影响因子：
1.7
作者：
Danev, R;Nagayama, K
通讯作者：
Nagayama, K
影响因子：
2.2
作者：
Cambie, Rossana;Downing, Kenneth H.;Jin, Jian
通讯作者：
Jin, Jian