| 摘要 |
PROBLEM TO BE SOLVED: To provide an electrodeless discharge lamp lighting device and an illumination device, of which, the electrodeless discharge lamp hardly goes off even at the time of a deep light control from right after its startup, in case the constant number of electronic components constituting a matching circuit is varied if only a little. SOLUTION: Power supplied to the electrodeless discharge lamp 5 is restrained by a duty-control circuit 20 at its startup and at the same time, the frequency of a switching element is controlled by a frequency control circuit 6 to fix the frequency after lighting of the electrodeless discharge lamp. If a quadric coefficient of a relation between an on-duty (d1) of a first switching element Q2 and a lower-limit light-control ratio (lt) of the electrodeless discharge lamp 5 approximated by a qudratic function is k, d1 is controlled so as to satisfy a relation of: d1=(50-√(lt-100)/k)×1.1. COPYRIGHT: (C)2004,JPO |
