| 摘要 |
A lighting device may be provided that includes: a heat sink; a member which has a polygonal pillar shape having at least three sides and is disposed on the heat sink, wherein the sides are inclined at a predetermined angle toward the center of the heat sink; and a light source which is disposed on at least one among the sides of the member, wherein the light source includes: a substrate; at least two light emitting devices which are symmetrically disposed on the substrate with respect to the center of the substrate; and at least two lens units which are disposed on the light emitting devices respectively, and consequently, it is possible to meet U.S. Energy Star and ANSI specifications, to remarkably improve rear light distribution characteristics and to remove a dark portion. |
| 主权项 |
1. A lighting device comprising:
a cover including an opening formed in a lower portion with an empty interior; a heat sink including a body and a member, the body including a top surface, an outer circumferential surface and a plurality of fins disposed on the outer circumferential surface, the member extended from the top surface toward the cover, the member having a polygonal pillar shape with at least three sides; and a light source disposed on at least one among the sides of the member, the light source including a substrate, a plurality of light emitting devices disposed on the substrate and a lens unit disposed on the light emitting devices, the lens unit covering the light emitting devices, a shape of a bottom surface of the lens unit corresponding to a top surface of the substrate, wherein an entire portion of the plurality of fins are arranged under the top surface of the heat sink, wherein the fin includes a first point having a maximum height from the outer circumferential surface of the heat sink, and a second point nearest the top surface of the heat sink, wherein an angle between an imaginary line passing through the first point and the second point, and the top surface of the heat sink is less than 135 degrees, and wherein a height of the member is greater than half a height of the cover on the basis of the top surface of the heat sink. |
