| 摘要 |
PROBLEM TO BE SOLVED: To prevent wear of an electrode, blackening of a light emitting part, illuminance insufficiency, a color tone defect of luminescent color, or the like due to too low an internal temperature of a light emitting part of an arc tube sealed with mercury, unstable discharge, non-evaporation of the mercury, and dropping of a lamp voltage when shortening an arc length by narrowing a distance between main electrodes of a high-pressure discharge lamp or when carrying out dimmer lighting of lighting the high-pressure discharge lamp in low electric power that is less than the rated power. SOLUTION: A heater 4 is provided for maintaining a minimum temperature in an inner face of the light emitting part 3 of the arc tube with a pair of the main electrodes 6R and 6L arranged facing each other at a temperature preventing accumulation of non-evaporated mercury when the lamp is in a stable lighted state. COPYRIGHT: (C)2004,JPO |
