| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To miniaturize an electrolytic capacitor of a rectifying smoothing circuit supplying power to a control power source circuit in a discharge lamp lighting device. <P>SOLUTION: In the discharge lamp lighting device in which a lighting state of a discharge lamp 3 is varied with an output signal of a lighting control circuit 11 after service interruption within the prescribed time, and the lighting state of the discharge lamp 3 is not varied with the output signal of the lighting control circuit 11 after service interruption other than the prescribed time, a control circuit 7 does not actually operate output voltage of the control power source circuit 8 with a control power source voltage switching circuit 10 by the operation of a service interruption detection circuit 13, and the lighting control circuit 11 drops voltage to a value continuing operation during at least the prescribed time. A coil L1, a switching element Q1, and a chopper having a diode D1 are optional, but if the chopper is used, output voltage of the control power source circuit 8 is supplied even to a control circuit 6 of the chopper. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
