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Frequency stability

  1. Mar 23, 2005 #1
    Does anyone know what it means to say that the frequency stability of a laser is 2 parts in 10E10, I gather that it means that the frequency shifts 0.02nm each side of the mean wavelength. But I can't find any resources that use the term parts.
  2. jcsd
  3. Mar 23, 2005 #2

    Claude Bile

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    The shift is usually expressed as a normalised shift w.r.t. the central laser frequency.

    [tex] \frac{\Delta\nu}{\nu_0} [/tex]

    This quantity is dimensionless and thus has no units.

  4. Mar 23, 2005 #3
    I know that equation and all the coherence stuff, it's just the terminology of 2 parts in 10e10, has thrown me and how to get the shift from that.
  5. Mar 28, 2005 #4

    Claude Bile

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    [tex] \frac{\Delta\nu}{\nu_0} = 2 \times 10^{-10}[/tex]

    If you know the central frequency of the laser, you can figure out the exact amount of shift.

    Last edited: Mar 28, 2005
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