| 摘要 |
PROBLEM TO BE SOLVED: To provide a high pressure discharge lamp with long life instead of using a discharging media containing thallium, enabled to remove ultra violet ray with simple structure. SOLUTION: A lighting device main body SPa comprises a reflection mirror m with an elliptic reflection surface, and a front glass fg on the surface of which, an optical interference film reflecting the light of 350-355 nm is formed. The reflection mirror faces a light irradiation opening of the lighting device main body SPa and fixed in the lighting device main body SPa. The front glass fg covers the light irradiation opening of the lighting device main body SPa. At the inside of the lighting device main body SPa, the high pressure discharge lamp device SPb is arranged so that the central part between electrodes of a luminescent tube IB can move to the position of the focus of the reflection mirror m, and to the front side or back side of the focus. |
