| 摘要 |
PROBLEM TO BE SOLVED: To stabilize a position of arc bright spots and prevent generation of flicker, on a high-pressure discharge lamp, in which mercury is enclosed by 0.20 mg/mm<SP>3</SP>or more. SOLUTION: A power supply device supplies alternating current to the high pressure discharge lamp in which mercury is enclosed by 0.20 mg/mm<SP>3</SP>or more, with a frequency selected from a range of 60 to 1,000 Hz as a stationary lighting frequency, and the high-pressure discharge lamp is lighted while inserting the alternating current of low frequency into the alternating current of the stationary lighting frequency at an interval having a length of half cycle or longer and 5 cycles or shorter, at an interval selected from a range of 0.01 second to 120 seconds, with frequencies selected from a range of 5 to 200 Hz which is lower than the stationary lighting frequency as the low frequency. COPYRIGHT: (C)2006,JPO&NCIPI |
