| 摘要 |
PROBLEM TO BE SOLVED: To make the restarting lighting of a high pressure discharge lamp possible even when the pressure of a sealed material on the inside of the high pressure discharge lamp is high by arranging a starting circuit part for applying superimposed two high voltage pulses to the high pressure discharge lamp and a ballast circuit part. SOLUTION: A lighting device has a starting circuit part 2 in which a first starting circuit 2a for generating a high voltage pulse sufficient to cause dielectric breakdown of a high pressure discharge lamp DL and a second starting circuit 2b for generating a high voltage pulse sufficient to keep the discharge of the high pressure discharge lamp DL are connected in parallel, the timing generating two high voltage pulses is synchronized, two high voltage pulses are superimposed and applied to the high pressure discharge lamp DL, and a ballast circuit part 1 which keeps lighting of the high pressure discharge lamp DL. Synchronization of timing generating two high voltage pulses is conducted by generating the both pulses in the constant phase of an AC power source. |
