| 摘要 |
PROBLEM TO BE SOLVED: To provide a high pressure discharge lamp lighting device capable of preventing the acoustic resonance phenomenon in accompany with the curve of discharging arc in an arc tube of a high pressure discharge lamp. SOLUTION: A tube voltage detector 16 is mounted for detecting the tube voltage of the high pressure discharge lamp 9, and a control circuit 17 is mounted for extracting the non-resonance frequency from the variation of the detected voltage, and controlling the driving frequency of MOSFET 10, 11 to make the lighting frequency be agreed with the extracted frequency. A voltage detector 18 is mounted for detecting the output voltage of a AC-DC voltage converting circuit 3, and ON-duty of the MOSFET 5 is controlled to adjust the output voltage to a given value. COPYRIGHT: (C)2003,JPO |
