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Modulate Visible Light

  1. May 29, 2008 #1
    I am aware that the reason we cannot see things around the size of atoms is due to the fact that the wavelength of light is too great. My question is why can you not modulate light, as you do with FM radios, to a higher frequency and therefore a shorter wavelength? Would that not enable you to at least see deeper into the realms of the unknown. I know that the wavelength of visual light is far to great to get anywhere near to an atom, but has this idea of modulation ever come to mind?

    This probably sounds crazy, but I hope people can see some thought behind it.

  2. jcsd
  3. May 29, 2008 #2

    Andy Resnick

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    Hence the development of electron microscopy.

    Frequency is related to energy- you can'tincrease the frequency without putting energy into the system. It's possible to perform frequency upconversion using nonlinear optics, and very high harmonics can be generated by hitting a plasma with a high-powered laser (wavelengths around 6 nm, IIRC- some of the next generation lithography sources). Synchotron radiation is another method, and the sources can be quite bright.

    But you want to go further: say 0.5 Angstrom wavelength. One problem is that the energy is so high, it messes up the thing you are looking at. X-rays ionize atoms, and you want energies WAY in excess of x-rays.

    So, people use alternate methods from far-field imaging and the diffraction limits: near field methods (scanning, TIRF, etc) is a big one. Use of atom-sized probes (Atomic force and related) is another.

    The state-of-the-art imaging technology is cryo-electron microscopy, AFAIK. Atoms can be imaged in a non-destructive way.
  4. May 29, 2008 #3

    I hate it how my amazing ideas always come a few decades late! I had an idea of trains on magnets, but that was already taken!

    Cheers for all the information. I liked the bit about the energy, and I am sure I have heard somewhere else I think it was something to do with quantum mechanics and finding the position and something else of a fermion.

  5. May 29, 2008 #4
    Swedish scientists has actually filmed an electron using " a robust and flexible setup for the generation, characterization and compression of attosecond pulses. "
    http ://www .atto . fysik . lth.se/
  6. May 31, 2008 #5
    "But you want to go further: say 0.5 Angstrom wavelength. One problem is that the energy is so high, it messes up the thing you are looking at."

    That defines the problem.

    Whether attosecond photon pulses reduces the problem remains to be seen, but I applaud the effort.
  7. May 31, 2008 #6
    Here is the link Yor_on posted.


    Can someone expand on the idea of the enrgy being so high it messes up the reading. I understand the basic concept, but I have a feeling I have read about something related to this in Quantum mechanics. Any ideas?

    Thanks for all your help though!
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