Abstract: A light source and a method for operating the same are disclosed. The light source includes a light emitter and a controller. The light emitter generates light in response to a control signal coupled thereto. The light emitter is characterized by an age related to the amount of light that has been cumulatively generated by the light emitter, the generated light for a given control signal changing with the age. The controller measures the age of the light emitter and generates the control signal based on the desired light intensity and the measured age of the light emitter. In one embodiment, the controller stores an age value for the light emitter, and the controller determines the control signal in response to an input signal specifying a desired light intensity from the light emitter, the controller updating the age value each time the control signal is determined.

Abstract: In one embodiment, light emitted by a plurality of solid-state light emitters is mixed by mounting the plurality of solid-state light emitters on a transparent to translucent substrate so that they primarily emit light away from the substrate. The light emitters are then covered with a transparent to translucent encapsulant; and the encapsulant is coated with a reflective material that reflects light emitted by the light emitters toward the substrate. Related apparatus is also disclosed.

Abstract: Illumination apparatus includes a support structure, at least one light emitting element, and a heat sink thermally coupled to the light emitting element. The light emitting element and heat sink are moveable in relation to the support structure. An actuator system moves the at least one light emitting element and the heat sink with respect to the support structure.