| 摘要 |
PROBLEM TO BE SOLVED: To provide a discharge lamp lighting device capable of lighting a discharge lamp without causing unevenness of luminance by preventing the discharge lamp from being half lighted by an insufficient lamp current in the curved portion of the lamp. SOLUTION: This discharge lamp lighting device is equipped with the discharge lamp 1 curved in a U shape, a power supply 6 to feed a lamp current, a coil-shaped current sensor 3 overlaid on the periphery of the U-shaped curved portion of the discharge lamp to convert the induction field of the lamp current flowing in the discharge lamp to the magnitude of a current and output it, a lamp current monitoring circuit 4 to monitor the lamp current flowing in a lamp tube by the magnitude of the current output by the current sensor, and a feedback circuit 6 to feedback-control an impressed lamp current by comparing the feedback value of the lamp current with a comparison value. The actual lamp current flowing in the curved portion of the lamp is monitored, and the impressed current is thereby controlled by adjusting the impressed current to the discharge lamp by the magnitude of the lamp current so that the lamp current required for discharge flows. COPYRIGHT: (C)2009,JPO&INPIT |
