Abstract: An LED light bulb in the shape of an incandescent light bulb having an engagement end that is insertable into a light fixture socket; a diffuser provided at a second opposed end of the LED light bulb and a heat sink that extends from the engagement end to the diffuser. The heat sink comprises a plurality of fins extending in the axial direction, the fins forming an exterior surface of the LED lightbulb, the heat sink having an axial inner end located at the engagement end and an axial outer end located at an axial inner end of the diffuser.

Abstract: An LED lamp includes: a substrate; a cluster of LEDs, which are arranged two-dimensionally on the substrate; and an interconnection circuit, which is electrically connected to the LEDs. The LEDs include a first group of LEDs, which are located around the outer periphery of the cluster, and a second group of LEDs, which are located elsewhere in the cluster. The interconnection circuit has an interconnection structure for separately supplying drive currents to at least one of the LEDs in the first group and to at least one of the LEDs in the second group separately from each other.