ISSN 2079-3537      

Scientific Visualization
Issue Year: 2013
Quarter: 4
Volume: 5
Number: 4
Pages: 71 - 87
Authors: V. Debelov (Russian Federation), D. Kozlov (Russian Federation)
  The paper is recommended by program committee of 23rd International Conference on Computer Graphics and Vision GraphiCon’2013.
Address: V. Debelov
Institute of Computational Mathematics & Mathematical Geophysics SB RAS, Novosibirsk, Russian Federation
D. Kozlov
Novosibirsk State University, Novosibirsk, Russian Federation
Abstract: Light can be polarized, unpolarized, and partially polarized. It can be linearly, circularly, or elliptically polarized.
Recently in many papers on photorealistic rendering definite attention has been given to light polarization. In fact, by polarized ray rendering one can obtain images differing considerably from those obtained via rendering by unpolarized ray. Rendering of crystals (especially of optically anisotropic ones) is impossible if polarization is not taken into account.
In addition to programs of calculating photorealistic images of 3D scenes with more or less realistic optical materials of scene objects and parameters of light sources, there exist programs of constructing and calculating optical devices – from simple lenses to complex optical systems. The currently updated versions of many of these programs contain a polarized ray tracing mode. To debug device constructions, some of the programs provide the user with means for displaying the polarization parameters. The traditional text table format of representation of a fully or partially polarized light ray is most widely used.
Scientific visualization often presents various real-world objects and their parameters in the form of images. Optical design programs have means for visual representation of polarization for a selected plane in the form of polarization ellipses, slope angles, and eccentricity of ellipses. Visual representation of polarization with the Poincaré sphere visualization tool is also used.
In this paper, the degree of ray polarization in a scene and its characteristics are represented graphically with the help of images which differ from those in the traditional ray intensity visualization and from the above representation of polarization. That is, the degree of polarization and the degree of ellipticity are represented in the form of half-tone maps on a selected plane in the space of the scene or in the space of the optical device being constructed.
This method of graphical representation of polarization for visual analysis can be of interest in itself. It can also be used to debug algorithms of rendering by polarized ray using well-known facts from optics and simple scenes with complex optical materials.
Language: English