Measuring transparency

1. Sep 15, 2010

Littlepig

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. Sep 16, 2010

Dr Lots-o'watts

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.

3. Sep 19, 2010

lewdtenant

try looking up "transmitted wavefront"

4. Oct 5, 2010

lewdtenant

I probably should have said "transmitted wavefront error", but I'm not even sure that's what you're looking for. oh well...