DISCHARGE LAMP LIGHTING DEVICE AND LUMINAIRE

摘要

PROBLEM TO BE SOLVED: To reduce electrical stress in remounting a discharge lamp without impairing a dimming function even if one or more of a plurality of the discharge lamps are removed. SOLUTION: This discharge lamp lighting device comprises: a D.C. power supply for converting a commercial voltage to a D.C. voltage; an inverter for converting the D.C. voltage to a high frequency; an inverter control part for controlling a switching element of the inverter; a plurality of resonance circuits connected in parallel with the output of the inverter and each comprising an inductor and a capacitor; a plurality of discharge lamp loads connected to the resonance circuits; and a load detection part for detecting whether or not the discharge lamp load(s) is/are mounted. When one or more discharge lamps out of the plurality of the discharge lamp loads are not mounted or in a non-lit state, a modulation operation in a predetermined range in an oscillation frequency modulation operation range of the inverter control part is prohibited. COPYRIGHT: (C)2004,JPO&NCIPI