DISCHARGE LAMP LIGHTING DEVICE

摘要

PROBLEM TO BE SOLVED: To always obtain excellent start-up characteristic by reliably transferring a glow discharge to an arc discharge, after a discharge lamp starts discharging at a high voltage generated by resonance and is put in the glow discharge condition. SOLUTION: This discharge lamp lighting device comprises an AC-DC-AC type conversion circuit 11a and a load resonant circuit 12 which is connected to the output of the conversion circuit 11a and is composed of an inductor L1, a capacitor C1 connected in series to this inductor L1 and a discharge lamp DL connected parallel to this capacitor C1. A control circuit 13 to adjust a duty difference between a FET Q1 and a FET Q2 so as to generate a desired high voltage in non-discharge period and in a designated period after the start of discharge, and a control circuit 14 to adjustingly control a voltage V2 so as to vary inversely as the duty difference of the FET Q1, Q2.