| 摘要 |
PROBLEM TO BE SOLVED: To improve the quality of a light distribution, to realize miniaturization and also extend a service life by preventing a main part of a seal for sealing a sealable part such as a small-diameter cylindrical part of a translucent ceramics discharge container from being substantially exposed toward an inside surface side and by arranging a lamp axis in a state of almost perpendicular to an optical axis. SOLUTION: When the lamp axis of a high-pressure discharge lamp HD is so arranged as to be almost perpendicular to the optical axis of a reflecting mirror M, a structure is so formed that a main part of each seal 4 for sealing a sealable part such as a small-diameter cylindrical part 1b or the like is not substantially exposed toward the inside surface side of the reflecting mirror M. Thereby, because excessive temperature rise of the seal 4 during lighting it is prevented, the occurrence of leakage due to the excessive temperature rise of the seal 4 can be reduced. Therefore, the problem of a short service life due to the excessive temperature rise of the seal 4 can be resolved, and the reflecting mirror M (lighting system) can be miniaturized. Because a luminescent part becomes small, the light distribution by means of the reflecting mirror M becomes sharp and the turbulence of the light distribution can be reduced. |
