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Measuring transparency

  1. Sep 15, 2010 #1
    Hi there.

    I was recently working out some expressions in Electro-Dynamics, to calculate reflexion and transmission coefficients. Ok, I reach some Fresnel equations. However, real materials are not so perfect, in sense that they are perfect surfaces, with perfect everything. So, I wonder how this kind of topic is treated: what mainly distinguish an "opaque glass" transmission, where the light is transmitted with a lot of scattering in that way (that I cannot better explain than saying like opaque glass), or well polished glass, where the light scattering scarce. Physically speaking, how can I quantify transparency, having in account not only I.O.Refraction, but surface smoothness, "kind of material used" (opaque metal or glass), etc. Which mean: what are the minimum (Physical and experimental measured) parameters, that define transparency of any material?

    Where can I find that kind of physical approach? (bibliography)

    Thank you very much,
    littlepig
     
  2. jcsd
  3. Sep 16, 2010 #2
    Am I partially answering your question if I I say that surface "perfection" can be measured by quantifying the roughness Ra?

    http://en.wikipedia.org/wiki/Surface_roughness

    It's measurable, and it affects transparency, but I'm not sure how it fits in with standard optics theory. Surface and internal media probably have to be treated separately. I think Ra can only be part of the answer (if it even is).

    In any case, I'll be interested in other answers.
     
  4. Sep 19, 2010 #3
    try looking up "transmitted wavefront"
     
  5. Oct 5, 2010 #4
    I probably should have said "transmitted wavefront error", but I'm not even sure that's what you're looking for. oh well...
     
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