Patent ID: 8764226

Claim:
An illumination module, comprising: a support member; a plurality of light emitting diodes (LEDs) on the support member; a reflective sheet on the support member, wherein the reflective sheet includes a plurality of holes therein that are arranged to correspond with locations of the LEDs on the support member, and wherein the LEDs are at least partially positioned within the holes; and an optical film above the support member and defining an optical cavity between the reflective sheet and the optical film into which light is emitted by the LEDs, wherein the optical film and the reflective sheet are configured to recycle light in the optical cavity by reflecting some light emitted by the LEDs back into the optical cavity and transmitting some light emitted by the LEDs out of the optical cavity; wherein the plurality of LEDs comprises LEDs having chromaticities within about a seven step Macadam ellipse about a point on a blackbody radiation curve on a 1931 CIE chromaticity space from a correlated color temperature of 2500K to 8000K, and wherein the LEDs have different optical characteristics, wherein chromaticities of the LEDs are selected so that a combined light generated by a mixture of light from the LEDs comprises light having about a target chromaticity; and wherein each of the LEDs of the metameric pair has a luminosity that is inversely proportional to a distance of a chromaticity of the LED to the target chromaticity in a two-dimensional chromaticity space.