| 摘要 |
PROBLEM TO BE SOLVED: To provide a discharge lamp lighting device for detecting anomaly such as short circuiting of a lamp and low impedance when a high-intensity discharge lamp of a type free from sealed-in mercury is used. SOLUTION: This discharge lamp lighting device is equipped with a DC power supply 1, a power conversion part 3 connected to the power supply 1, a high-intensity discharge lamp 5 of the type free from sealed-in mercury connected to the conversion part 3 via an ignitor 4 for generating high-voltage pulses, and a control part 6 for driving the conversion part 3 so that appropriate power is supplied to the discharge lamp 5. The control part 6 is equipped with a lamp impedance detection means 718 for detecting lamp impedance before the start of the lamp, and has the function of determining by means thereof that the discharge lamp 5 has impedance equal to or less than a prescribed value and stopping the supply of power to the discharge lamp 5 if a detected lamp voltage value is equal to or less than a first prescribed voltage value while the lamp is on. COPYRIGHT: (C)2004,JPO |
