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Laser Dispersion

  1. Jan 17, 2007 #1
    hey guys, i'm currently doing a project on laser beam, and just wondering what material i can use to disperse a laser beam so it hit a surface with more surface area.


  2. jcsd
  3. Jan 18, 2007 #2
    You mean something like a lens? A microscope objective works well - anything with a very short focal length will expand the beam without needing too much space.
  4. Jan 18, 2007 #3
    yes a lens, something small and thin

    do you know where i can buy it from?

  5. Jan 18, 2007 #4
    Try just bouncing it off a slightly curved scrap of aluminium foil from the kitchen. It's keeping the beam collimated that's supposed to be difficult.
  6. Jan 18, 2007 #5

    Claude Bile

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    Science Advisor

    Any lens will do the trick. You could even do it without a lens if distance is not an issue using the laser beams natural divergence.

    On a nit-pickky note, the term dispersion is generally reserved for a spread in frequency of a laser beam, not space. The term divergence is generally used for spatial spreading.

  7. Jan 18, 2007 #6
    Edmund Scientific sells lots of cheap lenses, or - if you don't care about the quality of the expanded beam - go to a local toy store and find something like a small glass or plastic ball (or cylinder). A camera lens works too, but needs a lot of space. You could also break open a Christmas ornamental ball and reflect the beam off the inside surface at an angle.
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