| 摘要 |
<p>A device for lighting and dimming a plurality of filament lamps are provided which eliminates the effects of harmonic distortion on its power supply. Lamp control circuits (1-1 to 1-n) are provided corresponding to filament lamps (4-1 to 4-n). The lamp control circuits (1-1 to 1-n) supply current to the filament lamps (4-1 to 4-n) when switching elements are on, while it allows the energy stored in inductors (L) to energize the filament lamps when the switching elements are off. The on/off operation is repeated so as to supply current of substantially the same waveform as the input current. A control section (3) controls the current for varying the duty factor of the on/off signal to the switching elements and also supplies the lamp control circuits (1-1 to 1-n) with the on/off signal with deviated timing.</p> |
