| 摘要 |
PURPOSE:To enable the supply of rectangular waveform current having less high-frequency components to a discharge lamp with a single capacitor by connecting the capacitor in parallel to the discharge lamp and using the capacitor for smoothing positive and negative rectified current output circuits. CONSTITUTION:When a switching element 51 is turned ON and another switching element 52 OFF respectively by a control signal from a drive circuit, positive pulsating current as half-wave rectified through a rectifying element 31 from one end (a) of the secondary winding of the output transformer 23 of a high-frequency inverter 2 is smoothed with a capacitor 4 connected in parallel to a discharge lamp 6 via the switching element 51 and smoothed direct current is fed to the other end (b) of the secondary winding of the output transformer 23 in an arrow A direction with the discharge lamp 6. Then, when the switching element 51 is turned ON and the switching element 52 OFF after the passage of the predetermined time, the direct current is supplied to the lamp 6 in a direction opposite to the arrow A. According to the aforesaid system, it is possible to supply the discharge lamp 6 with rectangular waveform current having less high-frequency components via the single capacitor 4. |
