| 摘要 |
PROBLEM TO BE SOLVED: To provide rated lamp power even when an inductance or the like of an exciting coil varies because of dispersion in a production time and change over aging, in an electrodeless discharge lamp lighting device, and to prevent break of a high-frequency power source in the case of extinction of an electrodeless discharge lamp. SOLUTION: A portion between drain sources of a high-frequency power source 1 is connected to the first matching circuit 2a, the circuit 2a is connected to the second matching circuit 2b via a coaxial cable 5, the circuit 2b is connected to an exciting coil 4, and the coil 4 is wound, for example, around a discharge lamp 3. When a constant of a circuit element constituting a closed circuit not including the high-frequency power source 1 and including a load out of elements constituting the matching circuits 2a, 2b varies, a characteristic impedance and a delay time of the coaxial cable 5 are selected to make an internal loss of the power source 1 substantially constant, and to be inductive when the load is viewed from an output terminal of the power source 1. |
