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Please identify pictures

  1. May 6, 2008 #1


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    I was playing with a laser pointer and a concave mirror and I managed to get a 5mm beam to spread over a 30cm area.
    http://img361.imageshack.us/img361/1884/mspaintfg0.png [Broken]
    http://img228.imageshack.us/img228/1866/lpuc9.jpg [Broken]
    http://img228.imageshack.us/img228/3581/lp0ii9.jpg [Broken]

    The irregular pattern remained stationary even when I moved the beam, so I guess it's due to (a) irregularities in the mirror or (b) impurities in the laser's lens?
    Last edited by a moderator: May 3, 2017
  2. jcsd
  3. May 6, 2008 #2
    I expect you are talking about a speckle pattern... Look up laser speckle in Wikipedia...
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