| 摘要 |
<P>PROBLEM TO BE SOLVED: To allow a discharge lamp to be usable over a long period. <P>SOLUTION: A drive device for the discharge lamp periodically switches a frequency fd of AC, at which the AC is supplied between two electrodes of the discharge lamp. The frequency fd is switched, by making the values of the frequency fd in a plurality of terms in a frequency fd switching cycle Tm3 different from one another. When predetermined conditions are satisfied, the frequency fd is changed non-monotonically, between a highest frequency term Th3 having the highest frequency fd in the switching cycle Tm3 and a lowest frequency term Tl3 having the lowest frequency fd in the switching cycle Tm3. <P>COPYRIGHT: (C)2011,JPO&INPIT |
