Patent ID: 7907804

Claim:
A planar illumination area comprising: a first discrete light-guide element comprising (i) a first light source emitting light therein, (ii) first and second adjacent non-parallel sidewalls spanning top and bottom surfaces, and (iii) a first out-coupling region in the top surface; and a second discrete light-guide element in contact with the first discrete light-guide element and comprising (i) a second light source, different from the first light source, emitting light therein, (ii) first and second adjacent non-parallel sidewalls spanning top and bottom surfaces, and (iii) a second out-coupling region in the top surface, only a portion of the second out-coupling region, including at least one sidewall of the second light-guide element, being disposed over and overlapping only a portion of the first out-coupling region including at least one sidewall of the first light-guide element, to define an overlapping region having an area, wherein (i) a light output power of the first out-coupling region within the overlapping region is less than a light output power of the first out-coupling region outside the overlapping region and (ii) a light output power of the second out-coupling region within the overlapping region is less than a light output power of the second out-coupling region outside the overlapping region, whereby the overlapping region emits a substantially uniform light output power over the area.