What is Electron microscope: Definition and 34 Discussions

An electron microscope is a microscope that uses a beam of accelerated electrons as a source of illumination. As the wavelength of an electron can be up to 100,000 times shorter than that of visible light photons, electron microscopes have a higher resolving power than light microscopes and can reveal the structure of smaller objects. A scanning transmission electron microscope has achieved better than 50 pm resolution in annular dark-field imaging mode and magnifications of up to about 10,000,000× whereas most light microscopes are limited by diffraction to about 200 nm resolution and useful magnifications below 2000×.
Electron microscopes use shaped magnetic fields to form electron optical lens systems that are analogous to the glass lenses of an optical light microscope.
Electron microscopes are used to investigate the ultrastructure of a wide range of biological and inorganic specimens including microorganisms, cells, large molecules, biopsy samples, metals, and crystals. Industrially, electron microscopes are often used for quality control and failure analysis. Modern electron microscopes produce electron micrographs using specialized digital cameras and frame grabbers to capture the images.

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  1. Dr Wu

    Microchip Imaging: What Magnification is Needed for Electron Microscopy?

    Assuming the use of an electron microscope, what magnification would be needed to image a computer microchip at the micrometer level? Thanks in advance.
  2. Philip Koeck

    The magnetic field just above a lens in an electron microscope

    I'm looking for an estimation or simulation of the magnetic field in the horizontal plane just above a typical lens in a transmission electron microscope. A rough cross section of such a lens can be seen here: electron lens - Bing images . The lens is cylindrically symmetric around the vertical...
  3. C

    Imaging Emitted Covid 19 Samples with an Electron Microscope

    After many months what comes out of the mouth and nose of someone infected with Covid 19 has not been directly observed. A single virus particle of Covid 19 is about 120 nanometers in diameter. This means that to see the virus, visible light wavelengths of 400 nm to 700 nm are too long to...
  4. A

    I Transmission electron microscope beam focusing

    So I'm reading up on this device and what I get is that in all electron guns once the electrons are emitted they would tend to repel one another so in order to make the beam focused instead of spread out across, one uses magnetic fields in the electron microscope, So after the focused beam hits...
  5. G

    Are the electrons in an electron microscope coherent?

    In an old fashioned electron microscope (the type I was meant to understand at university 50 years ago), are the electrons coherent, or do we just consider an electron interfering with itself? If they are coherent, how are they made coherent?
  6. O

    Any idea how to bake the column of a SEM?

    I am an undergraduate researcher and my university had an SEM donated to us by DOW chemical. It since has been without power and we have to bake the column and the gun chamber. Contacting the company they estimate $17k to send someone out to do it for us. I'm having difficulty finding material...
  7. G

    B Electron Diffraction and the DeBroglie Wavelength

    I've been reading up on electron diffraction for electron microscopy, and I have been trying to understand the proof for the wavelength of an electron in a tunneling electron microscope. The proof I have been trying to emulate begins as follows: It then says that I must account for...
  8. G

    B How does electron microscopy exploit wave/particle duality?

    I have been researching wave/particle duality, and I have trouble comprehending how electron microscopy actually exploits wave/particle duality to operate. From Wikipedia, " Wave–particle duality is exploited in electron microscopy, where the small wavelengths associated with the electron can...
  9. K

    X-Ray Shielding (Scanning Electron Microscope)

    Hallo everyone, I have a question about X-Ray shielding in a scanning electron microscope and I hope you can help me! The topic is that when electrons hit the specimen, characteristic radiation up to 10keV is generated. This radiation is blocked/decelerated my the surrounding tower and chamber...
  10. nilesh_pat

    About atom's image in electron microscope

    In Hydrogen atom, in center Proton and Electron revolving it. My question, is that enclosed in a cell, actually what we see in electron microscope. Regards Nilesh
  11. Telemachus

    Transmission Electron Microscopy

    I'm looking for a quick and well synthetized reference to the TEM technique. I'm writing a monography, we used TEM on a sample (just sended it to the lab, I dind't do the work). I don't have any reference, and I wanted to give a kind of introduction in the monography to TEM. I don't want a whole...
  12. F

    Electron microscope particle relativistic mass

    Homework Statement They were going to purchase an electron microscope, and wanted the electrons velocity to be as high as 25% of the speed of light after acceleration. There was a microscope at hand that had an accelerating voltage of 40 kV. a) How large is the electrons relativistic mass when...
  13. P

    Electron microscope theory - job opportunites

    thankyou to anyone reading this. I am starting honours in physics and have been given the opportunity to do a project that leads to a phd in the condensed matter theory. The guy I will be working with seems to specifically do work around the theory involved in electron microscopes. hes a great...
  14. B

    Scanning electron microscope

    Hi, I am working with a scanning electron microscope with the SED and it works fine. I have tried on several occasions to use the BSED without any success. All I get is a very faint dark image. Would you be able to give me some advice as to where I am going wrong? Thanks in advance
  15. J

    X-ray and electron microscope diffraction patterns

    Hey, I'm having trouble finding a clear answer anywhere. When you have a x-ray diffraction pattern, do the dark spots correspond to the positions of atoms? Or do they represent the position of atoms in reciprocal space or something like that? It would seem natural to assume that the peaks are...
  16. Z

    Exponental Tunnelling Factor (Electron Microscope)

    I'm reading a little bit about electron microscopes. It states, "the exponential tunnelling factor is proportional to the square root of the mass. So, the lower mass means lower exponential decay of the wavefunction". Would anyone be able to let me know what this exponential tunnelling...
  17. schrodingerscat11

    Getting the concentration from Scanning Electron Microscope

    Greetings! I am doing particle analysis using a JEOL 5310 Scanning Electron Microscope (SEM). Typically, people here in the lab report the results in % Element or % Atomic. I think the former refers to the weight percentage of an element and the latter to the stoichiometric ratio of...
  18. A

    Calculating Maximum Resolution of Electron Microscope

    Homework Statement Electrons are accelerated by 2450 V in an electron microscope. What is the maximum possible resolution? Me=9.11 x 10^-31kg and e= 1.60 x 10^-19 C Homework Equations I'm not so sure which equations to use for this question.. maybe the Planck's formula? λ=h/p...
  19. S

    Preparing biological samples for electron microscope

    Hi Guys, Ive been doing some work with E. Coli recently and I would like to image them under a scanning electron microscope. There are lots of papers with lots of different methods to prepare them for such a feat... but has anyone here actually done it and gotten a decent image? If so what...
  20. S

    Looking for HIV virus electron microscope images

    Hi, I am looking for some detailed electron microscop images of HIV virus itself. I need it bigger and more detailed then this: http://www.allvoices.com/contributed-news/9114517/image/80168820-hiv-virus-electron-micro-graph I would like to have some picture, not computer render or...
  21. S

    I'm trying to understand how an electron microscope works

    I know an electron microscope can collect x-rays emitted by electron holes, backscattered electrons as well as secondary electrons. I get that an electron's wavelength is much smaller than a photons, thus you get finer image resolution, but how exactly does a shorter wavelength mean a finer...
  22. A

    Conceptual question on wave-particle duality (electron microscope)

    according to wave particle duality particles such as electrons exhibit wave like properties. and the wavelngth is given by lambda=h/p, so increase momentum and get shorter lambda. This property is utilised in the electron microscope to get very short wavelengths and so have very high...
  23. A

    Conceptual question on wave-particle duality (electron microscope)

    according to wave particle duality particles such as electrons exhibit wave like properties. and the wavelngth is given by lambda=h/p, so increase momentum and get shorter lambda. This property is utilised in the electron microscope to get very short wavelengths and so have very high...
  24. K

    Scanning Electron Microscope Scanning Coils Kapton

    Hello, I am working on researching new ways to insulate some scanning coils on the SEM I work on. Currently we use Kapton to insulate the wires but it becomes brittle and wears over time easily. I am looking for alternatives to using Kapton for the scanning coils. Any ideas and suggestions...
  25. 1

    Quantum Physics: Electron Microscope

    Quantum Physics: Electron Microscope Homework Statement Consider electrons in the accelerating voltage of 15 kV used in an electron microscope with a 'lens' diameter D = 0.5 cm and focal length f= 50 cm. a) We require that the resolution is a tenth of the size of the object we want to...
  26. P

    Scanning Electron Microscope Images

    Would the resulting image by a scanning electron microscope be different if it scanned across the y-axis? SEMs have deflecting coils that move the electron beam from left to right (x-axis) rapidly while traversing down the y-axis to cover the entire specimen. Would the image you get after...
  27. D

    Electron Microscope Homework: Resolving Power of Atom

    Homework Statement The highest achievable resolving power of a microscope is limited only by the wavelength used; that is, the smallest item that can be distinguished has dimensions about equal to the wavelength. Suppose one wishes to "see" inside an atom. Assuming the atom to have a diameter...
  28. K

    Electron microscope question

    Is transmission electron microscope the original EM, and Scanning the better resolution one. What is the main difference between the two
  29. U

    Calculating Voltage & Velocity of Electrons in an Electron Microscope

    electrons in an electron microscope are accelerated form rest to a momentum making their wavelength 0.06 nm. 1. what is the voltage Vo needed for this? 2. What is the final electron velocity? For 1. E=\frac{hc}{\lambda}=\frac{1240eVnm}{0.06 nm} solve for E For 2. E=.5mv^2...
  30. A

    Resolution of an electron microscope for a given voltage

    how do you calculate the following question? what is the smallest distance that could possibly resolve for an electron microscope operating at 50KV?
  31. M

    Electron microscope problem

    Hi, I'm having trouble with a problem that I'm doing in my electricity and magnetism class. I can't even understand what it's asking and what the picture looks like. Here is the problem: In an electron microscope, a beam of energetic electrons, originally accelerated through a potential of...
  32. M

    A Virtual Scanning Electron Microscope

    A Virtual Scanning Electron Microscope, the link is provided to me (and anyone who reads that Journal) by the People at the Journal Science, The AAAS... Click http://www.vcbio.sci.kun.nl/eng/fesem/" [Broken]
  33. W

    Scanning electron microscope

    I know that optical devices are limited in the detail that can be seen because of the size of the wavelength of visible light. What is the limit, the smallest thing that can be seen with an optical device? Is the level of detail directly proportional to the wavelength? So what is the wavelength...
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