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This is an old revision of this page, as edited by 69.230.211.183 (talk) at 07:36, 29 September 2008. The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

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Harold Hillman

The heretic Harold Hillman claims that electron microscopy on cell material is a big methodological mistake. Frank A

Heretic? This is science, not religion. Hillman's claims don't explain why differing techniques should produce such similar results. He's not a heretic, just wrong. Average Earthman 16:51, 28 Feb 2004 (UTC)

Tunneling microscope as Electron microscope

Should this page not include the Scanning Tunneling Microscope under types as well? It is after all using electrons to image.

I've heard of scanning tunneling electron microscopes before. what are they? - Omegatron 01:58, Feb 4, 2005 (UTC)

Shorter wavelengths do not help with magnification, as this article states. They help with resolving power.

Against: When I think electron microscope, I see an electron gun or some sort of electron beam as an analog to optical microscopes... Tunneling microscopes are a different beast entirely, because the electrons are extracted form the sample. I used to work with an STM, but now I do biology. An STM would rip a biological sample apart, but electron microscopes are very popular.
I say we should remove the bulk tunneling microscopes info and only make a refence to them. Either way we don't need 4 paragraphs, when there is feature page. --vossman 21:35, 13 November 2005 (UTC)[reply]

I disagree.

I'm certainly NOT an expert here. My content comes directly from the Nobelprze.org website. If they have it wrong, please fix it. IMHO something needs to be said about the STM as a type of electron microsope, perhaps, as suggested below fewer paragraphs, with a link to its own page. frankatca 13 Nov. 2005 comment moved from top of page to chronological position

Merge of selected area diffraction

It's a technique specific to transmission electron microscopy, and therefore any merging should be with Transmission electron microscopy. Average Earthman 13:41, 28 January 2006 (UTC)[reply]

I second Average Earthman's vote - SA diffraction belongs in the TEM article. MarcoTolo 03:57, 5 February 2006 (UTC)[reply]

Not sure I agree, but I rather expanded the SAD article to make this a more useful discussion. Please edit the SAD article, in case I missed something or defiled the English language. Cm the p 19:22, 6 March 2006 (UTC)[reply]

Oppose. I think the microscope page should talk about a microscope and technique should get allocated to separate pages. Especially now that Cm the p has expanded the article. --vossman 22:16, 6 March 2006 (UTC)[reply]

I should say I wasn't actually voting *for* a merge, merely stating where the merge should be if one was carried out. Average Earthman 22:27, 6 March 2006 (UTC)[reply]

Well, we could consider if the SAD article should be merged with the electron diffraction article instead... O. Prytz 22:39, 7 June 2006 (UTC)[reply]

Oppose. Surely any merge should occur in the other direction. SAD is simply something which relates to electron microscopes...mpearse 09:39, 20 September 2006 (UTC)[reply]


I have removed the suggestion that that selected area diffraction be merged with this article, and suggest instead that it be merged with Transmission electron microscopy. See the SAD talk page. O. Prytz 23:08, 7 October 2006 (UTC)[reply]

Comment by "Graham Cliff"

I am an expert in AEM. The application of x-ray microanalysis in TEM and STEM. I take note of the absence of any discussion of SAD, and would add a need for CBED! This page, although very good, is incomplete. Perhaps it needs expansion? Graham Cliff.comment by 80.47.216.185, 20 August 2006

Test moved from Microscope

The following text was in the article Microscope but probably is better fitted here but I do not have the knowledge to ensure that it is well integrated. Apologies for the wholesale dump. Please feel free to delete from this discussion page folliowing any integration that may be appropriate. Velela 20:29, 22 April 2006 (UTC)[reply]

Following the above comment, I've trimmed anything that doesn't involve electron beams, leaving in the related detection techniques - we're now getting down to something that might be worth merging in, if someone is going to do it coherently rather than as a text dump. DrMikeF 14:49, 23 February 2007 (UTC)[reply]

Electron beam

File:Zeolite research 3DEM.jpg
A 3D-Electron microscopy/tomography showing a zeolite crystal in its atomic configuration. Courtesy of Utrecht University
see also:

Other / microanalysis

]

Common Classifications

See also

References

  • Max Planck Research Group
  • Nanotube helium sensors could bring atom beam microscope
  • [F1]:"Phase-coherent amplification of atomic matter waves" (Nature 1999/12, S. INOUYE, T. PFAU, S. GUPTA, A. P. CHIKKATUR, A. GÖRLITZ, D. E. PRITCHARD & W. KETTERLE )
  • D.A. MacLaren, H. T. Goldrein, B. Holst and W. Allison, Phase-stepping optical profilometry of atom mirrors, J. Phys. D., 36, 1842-1849, 2003
  • D. A. MacLaren, B. Holst, D. Riley and W. Allison, Focusing elements and design considerations for a scanning helium microscope (SHeM), SurfaceReview and Letters, 10, 249-255, 2003
  • Why use a Stem and not a Tem?


External links

um there should be a few sentences explaining WHY (wavelength of light vs electrons etc) electron microscopes work better than light ones...and there should be a pro/con section comparing the two (EM can only view dead samples as requires a vacuum, only has monochrome images, etc.) my $0.02.

Electromagnetic radiation

I think the introduction paragraph is wrong in saying that the electron microscope uses an electromagnetic radiation. The wave - particle duality principle applied to a beam of fast electron allows us to calculate an equivalent electron wavelength but this is the first time that I have heard an electron beam being equivalent to electromagnetic radiation such as visible light. DivakarR 08:46, 15 June 2007 (UTC)[reply]

You're right. I fixed it. --Heron 16:03, 15 June 2007 (UTC)[reply]

Sorry, it still says that electron microscopes use photons ("electromagnetic radiation"), and this is a huge mistake. VChivesud

References to be improved

Manfred von Ardenne is considered to be the father of scanning electron microscope and is a contemporary contributor to transmission microscopy along with Ernst Ruska. Among his numerous works are:


Manfred von Ardenne (1938). Das Elektronen-Rastermikroskop. Theoretishce Grundlagen. Zeitschrift fur Physik. 108, 553-572.

Manfred von Ardenne (1938). Das Elektronen-Rastermikroskop. Praktische Ausfurung. Z. Techn. Phys. 108, 407-416.

M von Ardenne and D Beischer. Untersuchung von metalloxud-rauchen mit dem universal-elektronenmikroskop . Zeitschrift Electrochemie 46, 270-277 (1940).


Manfred von Ardenne is one of the most prolific authors with publications in various fields of science throughout his life.

Esem0 06:49, 8 July 2007 (UTC) Esem0 06:52, 8 July 2007 (UTC) Esem0 06:57, 8 July 2007 (UTC)[reply]

I wonder if the electron microscope parts should be lised anywhere?

If they should should it be in a new article or an addition to this one? —Preceding unsigned comment added by 160.32.2.1 (talk) 14:52, 4 October 2007 (UTC)[reply]

TEM vs SEM

Transmission and scanning microscopes are quite different in construction and use. I'm going to try moving content off of this page to the subsidary pages where it is specific to each type of microscope. (I've been out of the industry for a while, so any corrections and help would be appreciated.) --IanOsgood 17:24, 19 October 2007 (UTC)[reply]

Diagram of electron microscope

The image could be cleaned up and used, but as it now stands it does not illustrate an electron microscope due to artifacts of the drawing. For example, the lenses are closed off from the beam entering, the objective lens is also blocking the path of the primary beam through the scope, there are unidentified structures in the scope. Please read the comments on the image talk page before restoring this to the article, as it downgrades the quality of the article with its incorrect illustration of an "electron microscope." —Preceding unsigned comment added by 207.62.177.227 (talk) 21:41, 10 December 2007 (UTC)[reply]

Okay, of course you are right. The article needed a diagram, and this was the best I could do. I knew there were problems with it, but it was meant to be a sketch - not specification! I tried to fix it, but PowerPoint, or I, are not up to the job. (I could align a real microscope quicker). So guys, here's the challenge, produce or find (or edit) a better free image that we can use in the article. Free images, like this bad one, can be edited just as articles. Which reminds me; why doesn't the anonymous user who wrote that excellent criticism on the image talkpage have a go at improving the article? (No sarcasm intended). --GrahamColmTalk 22:32, 10 December 2007 (UTC)[reply]
I will try to rewrite the article and the other EM articles when the term is over. The article needs work that should be done with references for readers to confirm the accuracy. —Preceding unsigned comment added by 207.62.177.227 (talk) 22:56, 10 December 2007 (UTC)[reply]

I made a new version, but I didn't understand all the comments. What else needs done? Tim Vickers (talk) 23:16, 10 December 2007 (UTC)[reply]


Quickly top to bottom: Label the high tension line 80,000 volts, not the gun itself. Add tungsten hairpin Filament outline, Cathode Cap and Anode. Label the section from Anode above "Electron Gun." Call the lenses Lenses, not coils. Coils does not need to be in parentheses. They are lenses. All lenses should be same size unless you elaborate to readers why C2 is so much smaller than C1. The two condenser lenses need separate labels because they are distinctly controlled in a TEM. The top one is Condenser Lens 1, the one below it is Condenser Lens 2. The apertures should be labeled what they are, "Condenser Aperture," "Objective Aperture," the Objective routinely changed in most TEM sessions, the Condenser changed for specific purposes. The intermediate lens (between objective lens and projector lenses) is missing. It and its Selected Area Diffraction Aperture need to be added. The assembly below the Condenser Aperture is, I guess, the Deflection Coils, and it should be labeled, and drawn distinctly from the lenses. The lenses should be inward facing square letter 'C's. See diagram at site on image talk page link and comment there. The specimen holder should be in a specimen exchanger, because you need a separate vacuum chamber unless you want to be venting and pumping down your entire column every time you put in a new specimen. There should be two projector lenses. They can be group labeled, no need to call them Projector Lens 1 and Projector Lens 2, which they are.

All coil and aperture openings and opening in bias shield and anode need to be precisely centered one above each other. Although the scope is made to look as if one is looking from the side, there is no purpose to drawing off-centered lenses and apertures in any microscope.

Also electron microscopes require stigmators due to the astigmatism in lenses is a primary limiting factor.

Do that and I will check a resource that can be referenced and fine tune it. —Preceding unsigned comment added by 69.225.2.17 (talk) 04:11, 11 December 2007 (UTC)[reply]

Wavelength and Frequency of Electrons

Does anyone know what wavelengths the electrons used in TEM microsopes are, and how their resolution compares to light such as gamma rays? 90.200.150.73 (talk) 15:28, 7 February 2008 (UTC)[reply]

Wavelengths for TEM electrons, with energies between 100keV and 300keV, are only a few picometers in size. Hence the angles for Bragg diffraction are much smaller than those for X-ray diffraction, since characteristic X-rays have wavelengths much closer to the separation between atoms (around 0.2 nanometers). Of course gamma rays of comparable wavelength interact very weakly with matter, while the high electrostatic charge to mass ratio of electrons causes them to interact rather strongly. Thermochap (talk) 21:41, 24 February 2008 (UTC)[reply]

Other Types

What about thermo scientific electron microscopy, am i missing it, is it called something else or is it not included? or is that just longhand for an electron microscope? --69.230.211.183 (talk) 07:36, 29 September 2008 (UTC)[reply]

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