DISCHARGE LAMP LIGHTING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a discharge lamp lighting device for maintaining a sufficient start voltage when starting a discharge lamp and suppressing the ripple currents in the discharge lamp when turned on. SOLUTION: The discharge lamp lighting device comprises a DC power supply circuit, polarity reversing circuits (switching elements Q2-Q5) connected in parallel to the output terminal of the DC power supply circuit for converting the DC power of the DC power circuit into AC power, and a loading circuit having the discharge lamp LA, an inductor L2 and a first capacitor C4 connected in parallel to the discharge lamp LA. Capacitance changing means (a capacitor C5 and a switching element SW) are provided for changing the capacitance of the capacitor so that the capacitance of the capacitor when lit is larger than the capacitance of the capacitor at the start. COPYRIGHT: (C)2003,JPO