A polaroid film is mounted in a circular frame. This linear polarizer is 25 cm in diameter. When observing unpolarized light through two of these polarizers, if they are in the crossed position no light can pass through them, but in the parallel position polarized light is transmitted. Four of them are available. The individual polarizers can be used to observe partially polarized light scattered from a clear tank filled with water and scattering particles.
A calcite crystal and many Iceland spar crystals are available to demonstrate double refraction. When a narrow light beam, a HeNe laser beam for example, passes through one of those crystals, one can observe the beam split in two projected onto a screen. Polarizing filters show the mutually perpendicular polarization of the split beams.
Light reflected from glass at an angle of 56 degrees is plane polarized, while the refracted light is only partially polarized. A light source and mounts for the polarizers are fitted on moveable radial arms of a turntable with a stand for glass plate on its center. On the turntable, a circular sclae is set and the Brewster's angle position is already drawn. This large set-up allows easy and clear demonstration of Brewster's Law or even just the polarizing filters action.
This experiment demonstrates the scattering of light by fine dust and small particles. It mimics the scatttering of sun light by a layer of dust near the earth's surface causing the sun to appear yellow, then orange, and finally red at sunset.