| 摘要 |
PROBLEM TO BE SOLVED: To provide a lighting device which starts safely and certainly and miniaturized, by providing priority for an action of a direct current power supply circuit than actions of a high-frequency power supply circuit, a starter circuit, and a matching exchange circuit when an electrodeless discharge lamp is started. SOLUTION: Input from a commercial AC power supply is converted into direct current of a direct current power supply of, for example, a booster chopper circuit. At a time when the direct current reaches a predetermined voltage, action of a high-frequency power supply circuit 3 is started, and the direct current input is converted to high-frequency current of hundreds kHz-hundreds MHz using a quartz oscillator. The high-frequency current is impressed on an induction coil 2 through a matching exchange circuit 6 in a starting impedance conformity condition, and generated high-frequency electromagnetic field is impressed to an electrodeless discharge lamp 1 in which discharge gas is filled. Furthermore, a starting circuit 5 impresses high voltage via a starting electrode 7 to light the electrodeless discharge lamp 1. Then, the matching exchange circuit 6 switches the present condition to a lighting impedance conformity condition. |
