| 摘要 |
PURPOSE:To prevent the damage of a lamp and an inverter circuit when the lamp life is terminated by detecting the abnormal voltage at the life terminal stage of a lamp with a self-holding type detecting circuit and reducing the output of the inverter circuit with an inverter output control circuit based on the detected signal. CONSTITUTION:A self-holding type detecting circuit 4 detecting the abnormal state at the life terminal stage of a discharge lamp is provided in conjunction with a discharge lamp lighting circuit, an inverter output control circuit 5 reducing the output of an inverter circuit 2 is connected to the inverter circuit 2 based on the signal detected by this self-holding type detecting circuit 4. The abnormal state at the life terminal stage of a lamp is detected by the self- holding type detecting circuit 4, the output of the inverter 2 is reduced by the inverter output control circuit 5 based on this detected signal. The damage of the lamp and the inverter circuit at the terminal stage of the lamp life can be prevented. |
