| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a discharge lamp lighting device and a lighting system, capable of improving the stability of light-emitting operation of a discharge lamp, when a dimming ratio drops. <P>SOLUTION: This discharge lamp lighting device is equipped with a dimming instruction receiving part 9 for receiving dimming instruction, and a control part 8 for controlling, the amount of power supply to the discharge lamp FL by an inverter circuit 6 according to the dimming instruction. The control part 8 is equipped with a resistance R1 to detect the amount of power supply, and a first feedback circuit 81 for controlling the amount of power supply, based on the amount of power supply detected by the resistance R1 and the dimming instruction, a resistance R5 for detecting the impedance of the discharge lamp FL, and a second feedback circuit 82 for controlling the amount of power supply based on an impedance detected by the resistance R5 and the dimming instruction. While a first feedback circuit 81 mainly controls the amount of power supply, when it is not less than a prescribed amount, the second feedback circuit 82 mainly controls the amount of power supply, when it is less than a prescribed amount. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
