Let us introduce HaloPol, our atmospheric crystal halo simulator, that calculates light polarization beyond intensity and color.

We are working hard to avoid bugs, however they still can be present. Feedbacks are welcome. We have verified the geometry, intensity and color patterns with the HaloSim halo simulator from Atmospheric Optics.

HaloPol Features

  • Light source editor
  • Easy-to-use crystal editor
  • Material editor
  • Raytracing viewer
  • Simulate once, display several ways
  • Interactive 3D viewer and several 2D viewers of the simulation results
  • Simulator engine based on Mueller-Stokes-formalism and Fresnel-equations
  • Simulations use spectral information
  • Results are converted to displayed colors by using proper colorimetric transformations
  • Sky background generated based on Rayleigh model of light scattering.
  • XML-based data storage

System Requirements

  • Windows XP, Vista, 7
  • OpenGL 2.1+
  • HaloPol is resource demanding, so a fast CPU with multiple cores and much RAM is required

Download HaloPol

The HaloPol installer for Windows can be downloaded from here.


HaloPol is copyright András Barta (Estrato Ltd.).

HaloPol is a free software, and intended for personal, educational and research use. You may not redistribute or sell this software in websites or by any other means. HaloPol is available for download in the hope that it will be useful, but it comes without any warranty.

If you publish any results for which you have used HaloPol, please refer this webpage (http://www.estrato.hu/halopol) as the source and András Barta (Estrato Ltd.) as the author of the software HaloPol.


Any feedback about bugs, feature requests, citations in publications are welcome.