miepython 1.3.2

Mie scattering of a plane wave by a sphere

miepython is a pure Python module to calculate light scattering by non-absorbing, partially-absorbing, or perfectly conducting spheres. Mie theory is used, following the procedure described by Wiscombe <http://opensky.ucar.edu/islandora/object/technotes:232>. This code has been validated against his results.

Extensive documentation is at <https://miepython.readthedocs.io>

This code provides functions for calculating the extinction efficiency, scattering efficiency, backscattering, and scattering asymmetry. Moreover, a set of angles can be given to calculate the scattering for a sphere.

When comparing different Mie scattering codes, make sure that you’re aware of the conventions used by each code. miepython makes the following assumptions

1. the imaginary part of the complex index of refraction for absorbing spheres is negative.
2. the scattering phase function is normalized so it equals the single scattering albedo when integrated over 4π steradians.

Installation

Just use pip:

pip install --user miepython

Usage

The following code:

import miepython

m = 1.5-1j
x = 1
qext, qsca, qback, g = miepython.mie(m,x)

print("The extinction efficiency  is %.3f" % qext)
print("The scattering efficiency  is %.3f" % qsca)
print("The backscatter efficiency is %.3f" % qback)
print("The scattering anisotropy  is %.3f" % g)

should produce:

The extinction efficiency  is 2.336
The scattering efficiency  is 0.663
The backscatter efficiency is 0.573
The scattering anisotropy  is 0.192

Detailed documentation is available at <https://miepython.readthedocs.io>

There are a few short scripts in the github repository.

• Extinction Efficiency of Absorbing and Non-Absorbing Spheres
• Four Micron Glass Spheres
• One Micron Water Droplets
• Gold Nanospheres

License

miepython is licensed under the terms of the MIT license.