| 摘要 |
PROBLEM TO BE SOLVED: To effectively prevent a side effect accompanying a flicker control in a high pressure discharge lamp lighting device.SOLUTION: In the high pressure discharge lamp lighting device including an AC power supply means for supplying rectangular wave AC current to a high pressure discharge lamp having an arc tube in which first and second electrodes are arranged in opposite directions, the first electrode being arranged on a neck side of a reflector and the second electrode being arranged on an opening side of the reflector, the AC current supply means includes a DC output means for determining a current value of the rectangular wave AC current and an AC conversion means for controlling polarity inversion of the rectangular wave AC current, wherein, assuming a current directed from the first electrode to the second electrode as a positive current and an opposite current as a negative current, a current-time product of the positive current is larger than the current-time product of the negative current during a first modulation period, the current-time product of the negative current is larger than the current-time product of the positive current during a second modulation period, the first and second modulation periods are repeated at a predetermined cycle, and a sum of the current-time product of the positive current is smaller than the sum of the current-time product of the negative current in the first of the predetermined cycle. |
