| 摘要 |
PROBLEM TO BE SOLVED: To provide a highly reliable heat sink structure which is usable in an LED lighting device, is small, achieves great improvement of integration density of an element, and is obtained at low cost.SOLUTION: A columnar member 6 having thermal conductivity is inserted into a wiring board 2, an insulation board 3, and a heat conductive board 7, which are laminated, so as to penetrate through these components. An LED element 1 is mounted on a flat surface preformed at a portion of the columnar member 3 which is exposed at the wiring board 2 side. A heat radiation fin 9 having a surface area set according to output of the LED element and including a smooth part is joined to an end part of the columnar member 6 which is exposed at the heat conductive board 7 side. |
