| 摘要 |
PROBLEM TO BE SOLVED: To provide a discharge lamp lighting device for obtaining the optimum light output without damaging the life of a lamp even if the ambient temperature of the lamp is varied. SOLUTION: In the discharge lamp lighting device which includes an invertor circuit 1 having a switching element to switch, in a high frequency, an output from a DC power source E, a resonant circuit 2 composed of an inductor T1 and a capacitor C1 applied the high frequency output, a discharge light La applied a resonant voltage of the resonant circuit 2, and a oscillation frequency control means 5 for switching an oscillation frequency of the invertor circuit 1, a switching means 4 is provided, wherein the switching means 4 operates the control means 5 so as to perform fixed power control to make loading electric power substantially constant in a range of a lamp impedance at around the rated lamp impedance of the discharge light La or higher, and to make the oscillation frequency substantially constant in a rage of the lamp impedance or lower at around the rated lamp impedance of the discharge light La. COPYRIGHT: (C)2004,JPO&NCIPI |
