| 摘要 |
PROBLEM TO BE SOLVED: To provide a soft start type lighting device for discharge lamp, which does not involve complication of a drive circuit or control circuit for an inverter and is not likely to generate abnormal oscillation. SOLUTION: A discharge lamp lighting device concerned is structured so that an inverter circuit 5 is connected with a DC power supply 2 through a boosting chopper circuit 3 and that a preheat type discharge lamp 4 is connected with the output end of the inverter circuit, wherein the inverter circuit 5 is operated while the chopper circuit 3 is left at a standstill for a certain period after the power is put on, and thereby the discharge lamp 4 is preheated. After a cetain period of time, the chopper circuit 3 is operated without changing the switching frequency of a switching element 12 for the inverter circuit 5. |
