Patent ID: 6874926

Claim:
An illumination system for use in a device having a plurality of key buttons disposed in a plurality of key locations, said illumination system comprising: a light source for providing light; and a light conduit adapted to receive at least a portion of the provided light, the light conduit having: a light guiding section for conveying the received light to areas near the key locations, wherein the light guiding section has two substantially flat boundaries and a plurality of side surfaces joining the two boundaries within the light guiding section for allowing the received light to propagate between the boundaries and side surfaces via reflection, and a plurality of light escape elements disposed in the light guiding section and located in the areas near the key locations to allow portions of the received light to escape from the light guiding section for illuminating the key buttons, wherein said light escape elements have a plurality of side facets, at least some of which reflect other portions of the received light along with one or more of the side surfaces within the light guiding section for allowing said other portions of the received light to propagate between the boundaries of the light guiding section.