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Intensity and frequence of light

  1. Jul 6, 2014 #1
    I have a doubt that can we increase the intensity of light without changing its amplitude and by increasing its frequency ? :what:
  2. jcsd
  3. Jul 6, 2014 #2


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    If you increase the frequency of light past a certain value, it becomes invisible to the human eye (for example, ultraviolet light, x-rays, and gamma rays are names for progressively higher frequency EM radiation.)
  4. Jul 7, 2014 #3


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    Frequency cannot imply intensity. Frequency decides the nature of EM radiation, so as Steamking said, increasing frequency will yield you a different kind of wave. In the visible region itself, changes in frequency will change the 'colour' of visible light, not it's intensity.
  5. Jul 7, 2014 #4


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    As the intensity of light increases you enter the realm of non-linear optics, which is studied with high power lasers. For example, when you shine ordinary light on a flat piece of glass it simply passes through - a small bit is absorbed, some is reflected, and the rest is transmitted.

    But as the intensity increases, the absorbed light can modify the glass slightly - through heating - and the glass may temporarily act as a lens, further focusing the light. This further increase in intensity may actually crack the glass.

    This is easy to due in a high powered laser lab; I've seen it done several times.

    With the appropriate crystals (birefringent) it is also possible to change the frequency of light. This was first done in 1962. This technique is used all of the time, and is how they make green laser pointers: https://en.wikipedia.org/wiki/Laser_pointer#Green
  6. Jul 19, 2014 #5

    Claude Bile

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    Sorry to nitpik, but this is just a thermo-optic effect, not a true nonlinear effect.

    True nonlinear effects (e.g. the Kerr effect) depend on intensity only, not temperature. This distinction is important as thermal effects are slow, whereas true nonlinear effects are very fast.

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