DISCHARGE LAMP OPERATING METHOD, AND BALLAST FOR OPERATING DISCHARGE LAMP

摘要

PROBLEM TO BE SOLVED: To improve an AC operation method for a discharge lamp, whose electric discharge is contracted to a focal point from an expanded fixed state in a cathode, so as to enable flickerless lighting by leading a discharge lamp current and providing an electrode forming a cathode and an anode alternately, according to a method defined by the AC operation. SOLUTION: Prior to limiting electric discharge in the electrode representing a cathode momentarily to a focal point from an expanded fixed state, the polarity of the discharge lamp current is switched.