Light emitting devices and systems having tunable chromaticity and methods of tuning the chromaticity of light emitting devices and systems

1. A method of forming a light emitting device package assembly, comprising:

providing a light emitting device package body;

defining first, second and third non-overlapping chromaticity regions in a two dimensional chromaticity space, wherein the first, second and third chromaticity regions are spaced apart in the two dimensional chromaticity space by respective regions having at least the size of a seven step MacAdam ellipse and wherein the first and second chromaticity regions comprise white light having a correlated color temperature not greater than 3000K;

providing a plurality of white light emitting devices that emit light having a chromaticity that falls within the defined chromaticity regions;

selecting at least three of the plurality of white light emitting devices, wherein each of the three light emitting devices emits light from a different one of the defined chromaticity regions; and

mounting the selected white light emitting devices on the light emitting device package body.

2. The method of claim 1 , wherein the first chromaticity region comprises light having a chromaticity that falls on a first side of a black body locus in the two dimensional chromaticity space, and wherein the second chromaticity region comprises light having a chromaticity that falls on a second side, opposite the first side, of the black body locus in the two dimensional chromaticity space.

3. The method of claim 1 , wherein each of the chromaticity regions comprises a plurality of pairs of complementary subregions, wherein respective subregions in a pair of complementary subregions are arranged opposite a center point of the chromaticity region from one another, wherein selecting the at least three of the plurality of light emitting devices comprises selecting at least six of the plurality of light emitting devices from at least six complementary subregions in pairs from respective pairs of complementary subregions.

4. The method of claim 3 , wherein selecting a pair of light emitting device from one pair of complementary subregions comprises selecting a first light emitting device having a first luminous flux from a first subregion that has a center point that is located a first distance from a center point of the chromaticity region, and selecting a second light emitting device having a second luminous flux from a second subregion that is complementary to the first subregion and that has a center point that is located a second distance from a center point of the chromaticity region, wherein the first distance is smaller than the second distance and wherein the first luminous flux is larger than the second luminous flux.

5. A method of operating a solid state luminaire including first, second and third groups of white light emitting devices, wherein each of the first, second and third groups of white light emitting devices emit light when energized having a chromaticity that falls within a respective one of first, second and third non-overlapping chromaticity regions in a two dimensional chromaticity space, wherein the first, second and third chromaticity regions are spaced apart in the two dimensional chromaticity space by respective regions having at least the size of a seven step MacAdam ellipse, wherein the first and second chromaticity regions comprise white light having a correlated color temperature not greater than 3000K, and the method comprising:

independently controlling current through respective ones of the first, second and third strings of white light emitting diodes to generate combined white light having a chromaticity that is intermediate the first, second and third chromaticity regions.

6. The method of claim 5 , wherein the light emitting devices include strings of light emitting devices connected in electrical series.

7. The method of claim 5 , wherein the first chromaticity region comprises light having a chromaticity that falls on a first side of a black body locus in the two dimensional chromaticity space, and wherein the second chromaticity region comprises light having a chromaticity that falls on a second side, opposite the first side, of the black body locus in the two dimensional chromaticity space.

8. The method of claim 5 , further comprising:

measuring the chromaticity of the combined light; and

altering current through at least one of the first, second and third strings of white light emitting diodes in response to the measured chromaticity.

9. A method of operating a solid state lighting apparatus, comprising:

providing at least first, second, and third white light emitting devices in the solid state lighting apparatus that emit light when energized having chromaticities that fall within respective first, second and third non-overlapping chromaticity regions in a two-dimensional chromaticity space wherein the first, second and third chromaticity regions are spaced apart in the two dimensional chromaticity space by respective regions having at least the size of a seven step MacAdam ellipse, and wherein the first and second chromaticity regions comprise white light having a correlated color temperature not greater than 3000K; and

tuning a chromaticity of combined light output by said solid state device to any of a plurality of points within a tuning region in the two dimensional chromaticity space defined by at least the respective chromaticities of said first, second, and third white light emitting devices.