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Building Materials Refractive Index?

  1. Jun 22, 2009 #1
    Building Materials Refractive Index??

    Hi all,

    does anybody know the refractive indices of these materials (used in houses)?
    - Wall bricks
    - Wood (used in doors)
    - Glass
    - Plastic
    - Concrete (in ceiling and floor)

    and any other common materials :)

    thanks in advance
     
  2. jcsd
  3. Jun 22, 2009 #2

    mgb_phys

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    Re: Building Materials Refractive Index??

    At what wavelength?
    The refractive index of something that isn't transparent isn't much use
     
  4. Jun 22, 2009 #3
    Re: Building Materials Refractive Index??

    I want it to model transmission of electro-magnetic waves (not light) ..

    at microwave frequency 2.4 GHz

    If it is possible I want the absolute refractive index

    thanks
     
  5. Jun 22, 2009 #4

    mgb_phys

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    Re: Building Materials Refractive Index??

    Google shows up a bunch of papers for microwave and Ka band frequency
    In practice the wavelength is similair to the thickness of building materials in a wall so modelling it might be trickier - I would imagine it's also very dependant on water content of something like brick/concrete
     
  6. Jun 22, 2009 #5
    Re: Building Materials Refractive Index??

    The index of refraction (= sqrt(dielectric constant)) in materials is a complex number, meaning that it has both refraction properties (like glass) and attenuation properties (like opaqueness). It is the attenuation property that reduces the transmission of microwaves.
    Propagator = ejωt-γz where γ is complex: γ = +/-sqrt(σμjω-εμω2)
    The ratio of attenuation to dielectric constant is called the loss tangent.
    tan(δ) = σ/εω. So attenuation is proportional to
    e-sqrt(σμω)z
    See
    http://en.wikipedia.org/wiki/Loss_tangent

    α β γ δ ε ζ η θ ι κ λ μ ν ξ ο π ρ ς σ τ υ φ χ ψ ω
     
  7. Jun 22, 2009 #6

    Andy Resnick

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    Re: Building Materials Refractive Index??

    There's a lot of available data online and elsewhere, for example:

    http://www.springerlink.com/content/xx771h5054762518/
     
  8. Jun 22, 2009 #7
    Last edited by a moderator: Apr 24, 2017
  9. Jun 23, 2009 #8
    Re: Building Materials Refractive Index??

    I don't have a springerlink account .. I would be so grateful if you just posted the refractive indices :)

    Thanks in advance
     
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