| 摘要 |
PURPOSE: A lighting device is provided to perform heat radiation by a natural convection method between the outside of a housing and an internal space, thereby improving efficiency of heat radiation without a heat radiating structure. CONSTITUTION: A light source(10) irradiates light. The light source is built in a housing(30). An optical member(50) is combined with the housing. A first air flow opening(51) is formed at least either a surrounding part or a central part(50a) of the optical member. By flowing of air between internal and external parts of the housing, heat generated from the light source is radiated. A second air flow opening is formed on the housing. A holder combines the optical member with the housing by being positioned between the housing and the optical member. |
