摘要 |
<p>An arrangement including an electrodeless discharge lamp having a sealed envelope enclosing an ionizable medium capable of emitting radiant energy when subjected to a radio frequency field and a circuit for operating the lamp. The circuit includes an oscillator for generating an output signal at a given radio frequency, an RF amplifier responsive to the oscillator output signal, and an output tank circuit including an induction coil and a capacitor connected in parallel. The RF amplifier includes a pair of semiconductor switches operating in a Class E mode. The induction coil is positioned in close physical proximity to the medium in the envelope for coupling to the medium an electric field having a magnitude sufficient to initiate ionization of the medium and a magnetic field for maintaining the ionization. In a preferred embodiment, the amount of EMI/RFI noise generated in the circuit is reduced by symmetrically driving the induction coil.</p> |