| 摘要 |
PROBLEM TO BE SOLVED: To provide a high-pressure discharge lamp exhibiting a sufficiently low starting voltage, a high-pressure discharge lamp lighting device using it, and a lighting system. SOLUTION: This high-pressure discharge lamp is provided with: an arc tube having a translucent ceramics discharge vessel 1 having a surrounding part 1a and a pair of small-diameter tube parts 1b communicating with both ends of the surrounding part, a pair of electrodes and a discharge medium; metallic coils C01 and C02 wound around a circumference of at least one of the small-diameter parts of the translucent ceramics discharge vessel and having one-side ends connected so as to be set at the same potential of that of the opposite electrode; an external tube for airtightly housing them; and a pair of external connection terminals connected to the arc tube and airtightly led out to the outside from the external tube. Capacitance between the pair of external connection terminals is 1.2-4 pF; in the metallic coils, each one-side end thereof is located in the vicinity of the boundary to the surrounding part, the winding pitch thereof is 100-500%, the length L2 thereof is 0.3-1.0 time as much as the length L1 of the small-diameter part; and the end on the side opposite to the surrounding part is connected to the other-side electrode so as to be set at the same potential. COPYRIGHT: (C)2007,JPO&INPIT |
