LIGHTING CIRCUIT OF DISCHARGE LAMP

摘要

PURPOSE: To improve so that the extinction of a lamp is not frequently caused just after lighting of a discharge lamp is started by generating resonance voltage having a high peak value to compensate restriking voltage of the discharge lamp generated when polarity of a rectangular wave is switched in a lighting circuit of the discharge lamp by a rectangular wave lighting system. CONSTITUTION: A lighting circuit 1 is provided with a DC voltage boosting circuit 5 and a bridge type DC-AC inverting circuit 7, and an inductor 26 is arranged in the rear stage of the DC-AC inverting circuit 7, and a metal halide lamp 9 is connected in series to this. An inductor 20 and a capacitor 21 are arranged between the DC voltage boosting circuit 5 and the DC-AC inverting circuit 7. An assembly by connecting a resistance 22 and a diode 23 in series to each other is connected in parallel to the inductor 20.