US Patent 8123375 Tile for solid state lighting

A solid state lighting tile (10) includes a substrate having a planar surface. A first plurality of solid state light emitting devices (LEDs) are on the substrate. The first plurality of LEDs (19) are connected in series to form a first string of LEDs of a first color having an anode contact (22) at a first end of the tile and a cathode contact (24) at a second end of the tile. A second plurality of LEDs are on the substrate. The second plurality of LEDs (21) are connected in series to form a second string of LEDs of the first color having a cathode contact (28) at the first end of the tile and an anode contact (26) at the second end of the tile.