| 摘要 |
PROBLEM TO BE SOLVED: To solve an inconvenience of brightness change happening at the time of switching, while it is necessary to switch alternate current for restraining lamp flicker when brightness is smoothly varied at lighting of a high-pressure discharge lamp. SOLUTION: The lighting device has a structure of variably controlling power supplied to the high-pressure discharge lamp by an arbitrary voltage, and changing amplitudes of a plurality of stepped waves in such waveforms that the wave form of the alternate current increases after commutation of rectangular waves until commutation of a plurality of stepped waves by an arbitrary voltage, and constantly controlling an average current of the alternate current. COPYRIGHT: (C)2006,JPO&NCIPI |
