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Patent

Circuit for starting and operating a gas discharge lamp

Kaj Jensen
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TLDR
In this article, a gas discharge lamp can be switched from its off-state to its on-state without emitting light flashes and further positively maintained the gas discharge lamps in its onstate when first ignited.
Abstract
A circuit is disclosed which is capable of positively shifting a gas discharge lamp from its off-state to its on-state without emitting light flashes and further positively maintains the gas discharge lamp in its on-state when first ignited. The circuit contains an oscillator device which generates and supplies an oscillator signal of a specific oscillator frequency from two output terminals of the oscillator device. It also contains a current limiting device an a parallel-resonance circuit comprising a capacitor and an inductor. The parallel resonance circuit has a frequency of resonance substantially identical to the oscillator frequency. The current limiting device and parallel-resonance circuit are connected in a series configuration across the output terminals of the oscillator device. Further, the gas discharge lamp is connected across or in parallel with the parallel-resonance circuit. The current limiting device preferably constitutes an inductor of a series-resonance circuit, the resonance frequency of which is lower than the oscillator frequency of the oscillator device. The oscillator device is preferably tuned to the frequency of resonance of the parallel-resonance circuit.

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Citations
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References
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