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Sellmeier equations & group delay dispersion

  1. Jan 25, 2010 #1

    I'm trying to take this Sellmeier equation,

    n^2 (λ)=1+ (B_1 λ^2)/(λ^2-C_1 )+(B_2 λ^2)/(λ^2-C_2 )+(B_3 λ^2)/(λ^2-C_3 )

    for which i have several sets of constants for prospective glasses, and convert it into a group delay dispersion graph, with axes of fs^2 vs wavelength.

    How do i rearrange the equation above (or convert the resultant graph) into a form i can use to find the GDD for the glasses?

    If it's easier, i could use the GVD instead of the GDD.



    Attached Files:

  2. jcsd
  3. Jan 25, 2010 #2
    Dispersion is generally some type of a derivative of refractive index. Sometimes people are interested in first order, or second order dispersion, and it's possible to have different definitions for each type (i.e. first or second derivatives with respect to either wavelength or frequency). Just take your definition of dispersion (in equation form) and apply it using derivatives and the chain rule if necessary.
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