| 摘要 |
PROBLEM TO BE SOLVED: To enable transition to low brightness having a low resonance output voltage without causing lighting failure, and to enable recognition of the brightness level currently used and a brightness level after changing it, when light is controlled. SOLUTION: When changing and controlling the brightness of a discharge lamp from first brightness to second brightness, after making a drive circuit once control the frequency of a high-frequency current so that the output current of a resonance circuit changes into a current higher than a target current by which the second brightness can be obtained, the drive circuit is made to control the frequency of the high-frequency circuit so that the output current changes into a target current. COPYRIGHT: (C)2010,JPO&INPIT |
