| 摘要 |
PROBLEM TO BE SOLVED: To control an electric power to a lamp by directly detecting a voltage applied to the lamp. SOLUTION: The discharge lamp lighting device 10 has a voltage detection circuit 70 disposed at an output side of an inverter 40. The voltage detection circuit 70 is constituted of a rectifying circuit 71 for rectifying AC voltage outputted by the inverter 40, and two resistors R1, R2 for voltage-dividing the output of the rectifying circuit 71. The voltage detection circuit 70 directly detects the voltage applied to the lamp L. Because the power for the lamp L calculated based on the detected voltage does not include a loss of an inverter circuit 30, more accurate constant power control can be done for the lamp L. COPYRIGHT: (C)2005,JPO&NCIPI |
