An illumination system employs a light distribution cylinder with an exterior
surface in the form of a plurality of progressively smaller-diameter cylindrical
steps. The outside surface of each cylindrical step is interrupted by V-shaped
grooves perpendicular to the axis of the cylinder. Each surface of these V-shaped
grooves acts to internally reflect divergent light from a light source positioned
at the end of the tube. The light distribution cylinders may be solid or hollow
and configured with bilateral symmetry to receive light from either end. The illumination
system rearranges divergent directional light from a light source into non-directional
light emitted in a cylindrical pattern useful for area illumination.