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Can i use a prism to diffract(separate?) ultralight or microwaves

  1. Apr 24, 2006 #1
    can i use a prism to diffract(separate?) ultralight or microwaves,
    if so, how far into the spectrum will it go?

    for example, when i look at a rainbow, and the rainbow ends after the violet and before the red, does it really end? or am i just unable to see the missing wavelengths?
  2. jcsd
  3. Apr 24, 2006 #2


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    Staff: Mentor

    Your retina is not sensitive to the near IR and UV radiation. You can get some kinds of glass to pass IR and UV, so you can make prisms that work for those wavelengths. For microwaves, I think you'd use a diffraction grating instead of a prism arrangement, but I'm not sure.
  4. Apr 25, 2006 #3

    Claude Bile

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    Science Advisor

    The wavelengths you can separate with a prism is really only limited by the absorption of the prism material itself. Silica for example, tends to absorb most wavelengths below about 3 microns. Similarly, for a rainbow, the wavelengths that are present will actually depend what gets absorbed by the atmosphere and what doesn't. So to answer your question, no the rainbow does not end, you just can't see the missing wavelengths.

    Prisms are, on the whole, the best way to separate broadband sources, diffraction gratings are best for high-resolution applications.

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