Patent ID: 8178894

Claim:
A backlight unit comprising: a board including a top surface and a bottom surface; at least two circuit layers on the top surface of the board, wherein the at least two circuit layers include a first circuit layer and a second circuit layer; at least one light emitting device on the top surface of the board and electrically connected to the at least two circuit layers, wherein the at least two circuit layers are electrically separated from each other and separately disposed on opposite sides of the at least one light emitting device; a lens on the at least one light emitting device and the at least two circuit layers, wherein the lens is disposed on the top surface of the board; and a light guide panel on the lens, wherein the lens comprises a center recessed portion at a top surface, a flat side surface perpendicular to the top surface of the board, a curved surface connecting the center recessed portion with the flat side surface, and a plurality of protrusion portions protruded in a lower direction on a lower surface of the lens, wherein at least one protrusion portion of the plurality of protrusion portions is disposed between the first circuit layer and the at least one light emitting device, and wherein at least one protrusion portion of the plurality of protrusion portions is disposed between the second circuit layer and the at least one light emitting device.