| 摘要 |
What is disclosed is a foil comprising optically refractive pyramidal elements, which each have a triangular base. The bases of adjacent elements are turned 180 degrees relative to each other. It has been found that such a foil has optically refractive characteristics upon incidence of electromagnetic waves thereon, which characteristics render the foil suitable for imparting a desired pattern, possibly in a desired direction, to the exiting waves. The pattern may be a uniform pattern, for example, so as to impart a uniform or diffuse light distribution to electromagnetic waves, for example visible light, from a concentrated light source.
|
