Patent ID: 6683418
Filing Date: 2004-01-27
Classification: H05B

Abstract:
An illumination lighting apparatus comprising:a resonance load circuit including a discharge tube having a filament for illumination; a power supply circuit for supplying a DC voltage; an inverter for converting the DC voltage into an AC voltage and supplying the AC voltage to said resonance load circuit; and a control circuit for adjusting electric power supplied to said resonance load circuit in accordance with operation conditions of said discharge tube after initial lighting in which said discharge tube starts lighting following preheating, wherein said control circuit controls an output voltage supplied from said power supply circuit to said resonance load circuit to a higher level when the voltage or current of said filament is larger than a predetermined value, controls the output voltage of said power supply circuit such that the output voltage becomes lower during a preheating period for preheating said filament in preparation for lighting of said discharge tube set by a time constant circuit, than during lighting of said discharge tube.