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Distance of laser focus

  1. Jan 31, 2012 #1
    I know that lasers will always have divergence due to diffraction. With that said, they dont diverge until after the point of focus, correct? Is there a limit to how far a laser can be focused?
     
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  3. Feb 1, 2012 #2

    Andy Resnick

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  4. Feb 1, 2012 #3
    Thanks for your reply. If one has a big enough aperture and the right optics, you could focus it out to 1 or 2 light-seconds couldnt you? Is there a limit to how far off a laser can be focused?
     
  5. Feb 1, 2012 #4

    Andy Resnick

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    There has been some work on deep-space communication systems (NASA's LCRD and LADEE experiments), and AFAIK there's a multi-satellite design by ESA that uses lasers to remain in a fixed configuration for gravitational wave detection (LISA)- not sure what stage in development they are, tho.

    Note that atmospheric turbulence/scattering makes long distance laser systems (Boeing's airborne laser system, for example) hugely complicated- the THEL (Nautilus) system was shelved.
     
  6. Feb 1, 2012 #5
    Hm, please elaborate. What do you mean by uses lasers to remain in a fixed configuration? Dyou have a link/site with more info? Also, yes Im aware of atmospheric effects on the beam, I meant strictly in a vacuum.
     
  7. Feb 2, 2012 #6

    Andy Resnick

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