High efficiency high intensity backlighting of graphic displays

摘要

Image display apparatus incorporating an enclosure having substantially opaque, substantially reflective interior surfaces. A light source emits light rays within the enclosure. An image-bearing surface is mounted in a front portion of the enclosure. The image-bearing surface bears a predefined image having transmissivity and reflectivity characteristics which vary as a function of position on the image-bearing surface, such that a substantial portion of the image is substantially non-transmissive and substantially reflective, and the remaining non-substantial portion of the image is substantially transmissive and substantially non-reflective. Accordingly, substantially all of the light rays which strike the reflective interior surfaces or strike the reflective portion of the image bearing surface are reflected within the enclosure, and substantially all of the light rays which strike the transmissive portion of the inward face are emitted through the image-bearing surface, thereby increasing luminance brightness of the image on an outward face of the image-bearing surface by repeated reflection of the reflected light rays within the enclosure until the reflected light rays strike the transmissive portion of the image-bearing surface.