Patent ID: 6597127
Filing Date: 2003-07-22
Classification: H05B,Y10S

Abstract:
A discharge lamp operating apparatus comprising:a discharge lamp; a dimmer for performing phase-control with respect to an input power source; and a ballast circuit for dimming and operating the discharge lamp in accordance with an AC voltage that is phase-controlled by the dimmer; wherein a relationship Z2&lE;(Vin/Vobâˆ’1)Ã—Z1â€ƒis satisfied,where Z1 (&OHgr;) is an impedance between an input terminal and an output terminal of the dimmer, Vob (V) is a breakover voltage of a bidirectional trigger diode that applies a trigger signal and is connected to a gate terminal of a switching element included in the dimmer, Vin (V) is an effective voltage of a commercial power source, and Z2 (&OHgr;) is an input impedance between the input terminals of the ballast circuit.