Abstract: An electrodeless discharge lamp comprising: an airtight container bulb made of a transparent material and enclosing a discharge gas; and a coupler (coil assembly body), contained in a cavity formed in the bulb, for generating a high frequency electromagnetic field by conducting a high frequency current in a coil to excite the discharge gas so as to emit light, wherein the coupler comprises: a pipe-shaped cylinder formed of a thermal conductor for heat release; a skeleton-shaped bobbin mounted on an outer surface of the cylinder along an axial direction of the cylinder; a core made of a soft magnetic material provided at an opening formed by the skeleton of the bobbin and being in substantial surface contact with the cylinder; and a coil wound around a surface of the skeleton-shaped bobbin and the core.

Abstract: An electrodeless discharge lamp comprising: an airtight container bulb made of a transparent material and enclosing a discharge gas; and a coupler (coil assembly body), contained in a cavity formed in the bulb, for generating a high frequency electromagnetic field by conducting a high frequency current in a coil to excite the discharge gas so as to emit light, wherein the coupler comprises: a pipe-shaped cylinder formed of a thermal conductor for heat release; a skeleton-shaped bobbin mounted on an outer surface of the cylinder along an axial direction of the cylinder; a core made of a soft magnetic material provided at an opening formed by the skeleton of the bobbin and being in substantial surface contact with the cylinder; and a coil wound around a surface of the skeleton-shaped bobbin and the core.

Abstract: A power source device restricts any increase in a switching current to switching elements commonly used in two such different power source circuits as chopper and inverter circuits, while maintaining control independence of these circuits, by setting a period in which among currents flowing to the commonly used switching elements, the current flowing at least from one of the power source circuits has a polarity inverse to that of the current from at least the other power source circuit, to be in mutually cancelling directions.

Abstract: A power device includes at least two power conversion circuits respectively having at least one of switching elements, at least one of which switching elements in these conversion circuits being used in common as an element constituting the at least two different power conversion circuits, a control device providing at least a period in which at least one of currents flowing from at least one of the different power conversion circuits to the commonly used switching element has a polarity inverse to at least the other one of the currents flowing from at least the other one of the power conversion circuits, so as to cancel each other, and a unit for detecting the state of the respective conversion circuits. The operation of the switching elements is thereby made modifiable in accordance with a lowering in the resistance of a load of the device, and the withstand voltage of the elements can be prevented effectively from rising even upon any fluctuation in the load.

Abstract: A power source device is so arranged that one of switching elements forming a plurality of power conversion switching circuits which is used in common during each switching cycle is made to have a switching period in which mainly a current is taken up from a power source of first one of the switching circuits, the switching period being varied in a zone in which an input voltage is higher than a predetermined voltage in a cycle of input voltage waveform. Any distortion of input current waveform occurring around lower voltage period of commercial AC source is thereby reduced, in the power source device wherein the power conversion switching circuits employ commonly the switching elements.