| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a discharge lamp drive method which can extend useful life and also can form a projection in an electrode to make it possible to drive the discharge lamp efficiently, irrespective of the luminance of the discharge lamp. <P>SOLUTION: A light source apparatus 1 comprises: a discharge lamp 500 having a pair of electrodes 610, 710; and a discharge lamp drive device 200 having an amplitude modulation part which amplitude-modulates an AC current whose frequency is 1 kHz to 10 GHz, both ends inclusive, and a luminance adjustment part which adjusts the magnitude of the AC current to adjust the luminance of the discharge lamp 500, and supplying the amplitude-modulated AC current to the electrodes 610, 710 to light the discharge lamp 500. The amplitude modulation part amplitude-modulates an AC current so that a first interval of AC current and a second interval smaller in amplitude of drive current than the first interval repeat alternately. Assuming that an average value of the amplitude of the drive current in the first interval is a, and that an average value of the amplitude of the drive current in the second interval is b, a ratio b/a of the amplitude a to the amplitude b is set according to the luminance of the discharge lamp. <P>COPYRIGHT: (C)2013,JPO&INPIT |
