| 摘要 |
PURPOSE:To detect the tube voltage of a discharge lamp in a simple structure to prevent failure and destruction by reducing the load on a lighting circuit due to abnormality of the tube voltage, for a discharge lamp lighting device provided with a dc step-up circuit. CONSTITUTION:After the voltage of a battery (dc power source) 1 is stepped up by a DC-DC converter (dc voltage elevating circuit) 2, it is converted into an ac mode by a DC-AC inverter (inverter circuit) 3, and is fed to a discharge lamp 5. The tube voltage of the discharge lamp 5 is detected out of the output of the DC-DC converter 2 by a tube voltage abnormality detection circuit 6, and an abnormality, if any, is displayed by an abnormality display part 12. |
