Patent ID: 7696964

Claim:
A light emitting diode (LED) light source system comprising: a support structure; clusters of LEDs mounted on the support structure in an array, the LEDs in each cluster including at least a first LED for emitting light of a first color, a second LED for emitting light of a second color, and a third LED emitting light of a third color, the first color, the second color, and the third color, when combined, generating light having a white point; a plurality of current sources, a first current source being connected to at least one LED emitting light of the first color, a second current source being connected to at least one LED emitting light of the second color, a third current source being connected to at least one LED emitting light of the third color, the current sources for controlling a brightness level of each color; at least one optical sensor connected to the support structure, the at least one optical sensor detecting a light output of a cluster when at least one LED in a cluster is energized; and a controller having a memory, the memory storing values for controlling an output current magnitude of each of the current sources so that a light output of the light source system has characteristics set by the values stored in the memory, the controller for calibrating a white point for all clusters by energizing LEDs within selected clusters and adjusting currents through LEDs in the selected clusters to cause a light output of each cluster to more closely match a target white point for that cluster based on values stored in the memory, wherein the controller is configured to perform the calibrating at various times over a lifetime of the light source system to offset degradation in the LEDs.