Patent ID: 8232718

Claim:
A tiled electroluminescent device that improves light emission uniformity and reduces reflection from ambient light, comprising: (a) a first and a second electroluminescent device tile, a portion of the edge of the first device tile abutted with a portion of the edge of the second device tile leaving a gap between the first and second device tile edges, each device tile comprising a substrate, having an optical index and a level of transparency, and an electroluminescent diode for emitting light according to a distribution that is substantially Lambertian, whereby light is directed along an oblique angle to the surface of the substrate of the first tile and through the edge of the first device tile; (b) a filler located in the gap between the abutting edges of the first and second device tiles, the filler having an optical index and a level of transparency matched to the optical index and transparency of the substrates of the first and second device tiles, whereby the light produced by the electroluminescent diode of the first device tile within the first range of oblique angles passes through the edge of the substrate of the first device tile, through the filler, and into the substrate of the second device tile before the light is absorbed or passes through an edge of the substrate of the second device tile and light produced by the electroluminescent diode of the first device tile within the second range of oblique angles passes through the edge of the substrate of the first device tile, through the filler, into the substrate of the second device tile before the light is emitted through the front surface of the substrate of the second device tile; and (c) a super substrate disposed over the first and second device tiles and affixed to the substrates of the device tiles, wherein the super substrate is a circular polarizer selected to reduce reflection from ambient light; and (d) a reflective element located only in the gap between the abutting edges of the first and second device tiles on the same side of tiled EL device as the electroluminescent diodes that reflects light passing through the filler.