Heat dissipation structure for solid-state light emitting device package

Abstract

A light emitting diode (LED) includes a heat dissipation structure characterized by having a heat dissipating fluidic coolant filled in a hermetically sealed housing where at least one LED chip mounted on a metallic substrate is dwelled inside. The heat dissipation structure is configured with a metallic wall erected from the metallic substrate, which is used to hold a transparent cap of the sealed housing in correct position. Furthermore, the erected wall surrounds in proximity with the at least one LED chip, so that the joule heat generated therefrom can be quickly spread out, through the heat dissipating fluidic coolant, to the erected wall, and then diffused along the wall down to the metallic substrate which adjoins with a larger external heat sink for draining the heat, thus preventing the at least one LED from overheating. The other characteristic of the invention resides in that the transparent cap of the sealed housing is made of transparent materials, wherein a convex portion contacted with the heat dissipating fluidic coolant is formed on the inner surface of the transparent cap. Hence if there is any air bubble existing inside the housing due to insufficient filling, it will not dwell in the field of line-of-sight due to buoyancy. The possibility of scattering the LED light due to existing of the bubbles therefore is avoided.