| 摘要 |
PURPOSE:To provide a discharge lamp lighting device equipped with only one inverter circuit, wherein the preheat current and the lighting current are varied to the respective optimum values. CONSTITUTION:A discharge lamp lighting device 8 according to the present invention has a control circuit part 4, which varies the oscillative frequency of an externally exciting inverter circuit part 2 between under and after the actuation of a timer circuit part 1, and in parallel therewith a preheat circuit part 3 shortcircuits, the terminals of the discharge lamp LA filament are shortcircuited when the timer circuit part 1 is in actuation. After actuation of the timer circuit part 1, the shortcircuit between the terminals of the discharge lamp fiament due to the preheat circuit part 3 is opened, and thereby the frequency of the high frequency current given to the terminals which is to be supplied to the discharge lamp by the inverter circuit part 2 is varied between at preheating and at lighting up, and even at the time of preheating, feeding to the terminals is made so that the high frequency current of the optimum amperage is supplied to the discharge lamp LA. |
