Quantifying Transparency in Materials: A Physical Approach | Resources Included

[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

 

[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.

 

[lewdtenant]

try looking up "transmitted wavefront"

 

[lewdtenant]

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

 

[alphy]

let

Hello littlepiglet,

Thank you for your question. Transparency in materials is a complex and multifaceted concept that can be measured and quantified in several ways. I would suggest looking into the field of optics and materials science for more information on this topic. Some key parameters that are commonly used to define transparency in materials include:

1. Refractive index: This is the measure of how much a material bends light as it passes through it. Materials with a higher refractive index tend to be less transparent, as they cause more scattering and absorption of light. This parameter is often used to quantify the transparency of materials.

2. Absorption coefficient: This is a measure of how much light is absorbed by a material as it passes through it. Materials with a higher absorption coefficient tend to be less transparent, as they absorb more light instead of transmitting it.

3. Surface roughness: As you mentioned, the smoothness of a material's surface can also affect its transparency. A rough surface can cause light to scatter in different directions, reducing the overall transparency of the material.

4. Material composition: Different materials have different optical properties, which can affect their transparency. For example, glass is typically more transparent than metal, due to its molecular structure and composition.

To quantify transparency in a material, it is important to consider all of these parameters and their interactions. This can be done through various experimental techniques, such as spectrophotometry, ellipsometry, and microscopy. Additionally, there are several theoretical models and equations that can be used to calculate the transparency of a material based on its physical properties.

Some recommended resources for further reading on this topic include:

1. "Optical Properties of Materials" by Mark Fox
2. "Introduction to Optics and Optical Materials" by Sergei Popov
3. "Materials Science and Engineering: An Introduction" by William Callister Jr. and David Rethwisch
4. "Handbook of Optical Constants of Solids" edited by Edward Palik

I hope this helps to answer your question and provide some guidance for further research. Best of luck in your studies.

Sincerely,

Scientist