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Material that blocks visible light but not uv light

  1. Dec 10, 2009 #1
    is it possible to have a material block high wavelength waves but not low length waves? Gamma rays can pass through objects that visible light cannot. Any thoughts?

    I was thinking a certain bandgap?
  2. jcsd
  3. Dec 10, 2009 #2


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    Aluminium; as long as you carefully knock out electrons from the atoms. A recent experiment used a laser to carefully knock out the electrons, and succeeded in making a small sample of aluminium transparent to "extreme ultraviolet radiation". I am not sure how transparent it would be to ordinary light.

    Difficulties with practical applications for this material are as follows:
    • Scientists only managed to get a tiny sample into this transparent state: less than a 20th of the width of a human hair in diameter.
    • The laser required needed a power burst similar to what is needed for providing electricity to an entire city (briefly).
    • The material remained in this state for about 40 femtoseconds.

    See Transparent aluminium is 'new state of matter at physorg.com; and the paper Turning solid aluminium transparent by intense soft X-ray photoionization by Bob Nagler et al in Nature Physics 5, pp 693 - 696 (2009), doi:10.1038/nphys1341

    There may be other materials that are easier to use... but I enjoyed reading about this one.
  4. Dec 10, 2009 #3
    wow, that was interesting! i guess people are still way off from figuring it out. Interesting that it seems like its a spacing problem, as gamma/xrays also pass through material with ease. anyone else have any articles on this type?
  5. Dec 10, 2009 #4


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    There are much less exotic materials that the weird aluminium one I mentioned at first. I've just had a quick look.

    "Wood's glass" (wikipedia link) is a form of glass that is treated to be opaque to almost all visible light, but transparent to near ultraviolet. You can also buy glass filters that are transparent to ultraviolet and opaque to visible. See this commercial site for some of the filters you can obtain.
  6. Dec 10, 2009 #5


    Staff: Mentor

    I think there are also "tan through" fabrics that are transparent to UV for swimwear.
  7. Dec 10, 2009 #6
    i think clouds can also do the same thing but am not sure whether it is a material or not?
  8. Dec 10, 2009 #7
    There are filters for blacklights (UV fluorescent lamps with short and long UV Hg lines) that block visible light.
    Bob S
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