| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an electrodeless discharge lamp lighting device and a luminaire capable of avoiding a wrong decision and lowering of an output power due to a no-load state decision promptly. <P>SOLUTION: By comparing a detected value ¾Vxs¾ of an output power of a power supply circuit with a predetermined no-load decision voltage Vth corresponding to a no-load decision threshold, a control by a no-load decision operation for determining whether it is in a no-load state is not conducted in a starting period Ts just after lighting up of the electrodeless discharge lamp when an output power of the power supply circuit is likely to be raised temporarily. With this arrangement, a wrong decision due to the detected value ¾Vxs¾ likely to be raised temporarily during the starting period Ts can be avoided. Further, as compared with a case where the no-load decision voltage Vth is raised more than a peak value of the detected value ¾Vxs¾ to avoid the wrong decision, an electrical stress can be reduced by lowering the no-load decision voltage Vth and lowering at an early state the output power of the power supply circuit by the no-load state decision. <P>COPYRIGHT: (C)2010,JPO&INPIT |
