Results 1 to 2 of 2

Thread: How to find MIE parameters?

  1. #1
    Joe Wolfgang Guest

    How to find MIE parameters?

    Many people want to use MIE correction to light scattering, but don't know how/where to get refractive index and imaginary coeff. values for their particular materials. any suggestions how to scientifically collect this data (other than current ISO standard for Laser Diffraction, which is great for common minerals, but not applicable to "real world" products).

  2. #2
    dcvaughn Guest

    Question RE: MIE Parameters

    Mr. Wolfgang,

    I see you posted this quite some time ago, but I'll put in my two cents. I'm not sure what you're doing, so I'll go ahead and post a few solutions depending on application.

    1. You're doing laser-light diffraction and you need "accurate" real and imaginary refractive index values. The RI of the material can be obtained using the Becke line method. If birefringent, then the average of two RIs is typically used. The imaginary part is then assumed to be in one of three categories: perfectly transparent, semi-transparent or opaque. Simply take a guess as to what category your sample belongs and go with it. For most non-spherical, anisotropic particles, calculated imaginary refractive indeces won't make a dent in the total error emanating from the irregular shape and birefringence of real world samples.

    2. You're working with laser-light diffraction and perfectly spherical, isotropic and transparent particles. In this case, it may make sense to find truer RI values. Keep in mind that true RI values do not arise from Mie theory per se, but from wave propagation theory. What you're really after is not to calculate the scattering function (the instrument does that), but to find to what extent your sample absorbs the incident light while it is refracting. To do this you'll have to find an accurate RI using the Becke line or other methods. Then you must calculate the imaginary component using the diameter of your particles, the electrical conductivity of your material and the wavelength of your incident light. I highly recommend the book "Light scattering by Small Particles" by van de Hulst.

    3. You're building an instrument and need to construct a rugged model. Can't help you there.

    I hope this helps you. Good luck.

Similar Threads

  1. How to Find Phosphor Content in Coke?
    By jsr4f7 in forum Sampling, Inspection & Statistics
    Replies: 4
    Last Post: 27th August 2010, 21:41
  2. How to find out - Wear or Heat Resistant?
    By sganesh in forum Trough Belt Conveying
    Replies: 5
    Last Post: 5th June 2009, 5:45
  3. Airlift Operating Parameters
    By a.sabeer in forum Pneumatic Conveying
    Replies: 3
    Last Post: 22nd April 2009, 11:06
  4. Rockbox Parameters
    By Liam B in forum Mechanical Conveying
    Replies: 7
    Last Post: 16th March 2008, 2:28
  5. Where to Find Grinding Media from SiC & WC
    By ezryakkerman in forum Size Reduction & Comminution
    Replies: 0
    Last Post: 27th July 2006, 17:28

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Single Sign On provided by vBSSO