Patent ID: 8866414

Claim:
A tunable light-emitting diode (LED) lamp for producing biologically-adjusted light, comprising: a base; a housing attached to the base; a power circuit disposed within the housing having electrical leads attached to the base; a driver circuit disposed within the housing; a plurality of LED dies electrically coupled to and driven by the driver circuit; and an intermediate base adapted to be removably attachable to the base and positionable in electrical communication with the driver circuit and the power circuit; wherein the driver circuit is adapted to drive the plurality of LED dies to emit a phase-shift light having a first spectral power distribution, a general illuminating light having a second spectral power distribution, and a pre-sleep light having a third spectral power distribution; wherein the phase-shift light is configured to affect a first biological effect in an observer; wherein the pre-sleep light is configured to affect a second biological effect in an observer; wherein in the pre-sleep light the driver circuit is adapted to drive the plurality of LED dies such that a blue output intensity level, in a visible spectral output range of between 380 nm and 485 nm, is less than 10% of a relative spectral power of any other peaks in the visible spectral output above 485 nm; wherein the intermediate base is adapted to couple with an Edison screw socket thereby positioning the intermediate base in electrical communication with the Edison screw socket; and wherein the intermediate base is configured to cause the driver circuit to operate the plurality of LED dies so as to emit one of the phase-shift light, the general illuminating light, and the pre-sleep light, or to emit no light.