| 摘要 |
PROBLEM TO BE SOLVED: To provide an electrodeless discharge lamp lighting device capable of performing deep dimming and reducing noises and improving startability at the time of dimming control. SOLUTION: A control circuit for controlling a high frequency circuit supplying high frequency power to an induction coil adjacently arranged on an electrodeless discharge lamp comprises a means for switching a full lighting action for continuously supplying voltage for making the induction coil light up the electrodeless discharge lamp, and an intermittent lighting action for alternately repeating a first period wherein the applied voltage of the induction coil becomes voltage for lighting-up the electrodeless discharge lamp and a second period wherein applied voltage of the induction coil becomes voltage capable of not maintaining lighting of the electrodeless discharge lamp so as to be a desired time ratio. When switching the first period and the second period, the voltage applied to the induction coil is continuously changed. When switching from the full lighting action to the intermittent lighting action, the time ratio between the first period and the second period is continuously changed until the time ratio becomes a desired time ratio. COPYRIGHT: (C)2009,JPO&INPIT |
