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Laser traveling through air

  1. Dec 17, 2007 #1
    Does laser traveling through air affect the air it travels through?
  2. jcsd
  3. Dec 17, 2007 #2


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    High energy lasers will ionize the air around them and do all sorts of funny things. The average laser beam will do nothing. "Laser" does not travel through air, because "laser" is a light emitting machine, not a "lasers go pew pew" ray.
  4. Dec 17, 2007 #3

    Claude Bile

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    A laser with a sufficiently short pulse duration and sufficiently high power will undergo what is known as filamentation, which is actually a dynamic balance between two opposing mechanisms - nonlinear Kerr self-focusing, which is the phenomenon whereby the local refractive index is dependent on irradiance. This essentially turns the air into a weak lens, causing the laser beam to converge (hence the term self-focusing). The opposing effect is plasma generation - which also turns the air into a weak lens, albeit a diverging one.

    The combined effect of these two phenomena is a laser beam that does not spread out as it propagates (however it is not a soliton). This is especially handy for LIDAR type applications.

  5. Dec 17, 2007 #4

    All i gotta say is that is the funniest quote i have ever heard. "pew pew" LOL. thanks for the comic releif
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