A polarized object cell is a cell containing polarized lenses which filter out light rays that would normally pass through and illuminate glass pieces commonly used in kaleidoscopes. This creates a dark background for the image because the light has been filtered out by the cross polarization of the lenses. However, when bi-refringent material is placed between the lenses, the light is bent (refracted) and therefore since the light rays are at a new angle to the lens, they can pass through and are seen as varied colors depending on the thickness of the bi-refringent material and the angle of the light ray. The range of colors is caused by the light rays bending at various angles.