| 摘要 |
PROBLEM TO BE SOLVED: To provide a discharge lamp lighting device, equipped with a half bridge inverter for preheating a filament electrode for enhancing flashing characteristic and improve the reliability of a thermosensitive resistor, and to provide a lighting system using this device. SOLUTION: This discharge lamp lighting device comprises first and second switching means Q1 and Q2 connected serially between DC power sources; a load circuit LC comprising at least a resonance inductance L2 and resonance electrostatic capacities C3 and C4, operated by high-frequency AC generated by the alternate switching of Q1 and Q2, and having a discharge lamp DL connected in parallel with respect to at least a part C4 of the resonance electrostatic capacities; and a feedback drive signal generating circuit DSG, comprising a thermosensitive resistor RPTC for feeding back the current carried in the load circuit and energizing a drive resonance circuit DRC to perform the on- control of Q1 and Q2, and also causing changing the resonance frequency of the drive resonance circuit DRC to change continuously at least, at the inputting of a power source. |
