1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

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

    User Avatar
    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.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook