Circuit arrangement for igniting and operating a discharge lamp

A method for igniting and operating a gas discharge lamp having a capacitor, a series circuit of an inductor, a transformer and the gas discharge lamp, the inductor acting as resonance inductor during ignition, the transformer acting as ignition transformer, and the capacitor acting as resonance capacitor, whereas during the operation of the gas discharge lamp the inductor acts as a lamp inductor, the transformer as filter inductor, and the capacitor as filter capacitor, the inductor and the capacitor forming a resonant circuit during the ignition, wherein the resonant circuit produces during the ignition a first voltage that results in a current through the primary winding of the ignition transformer, and thereupon a second voltage is produced across the secondary winding of the transformer, and the first and the second voltages are added together to form an ignition voltage in such a way that the ignition voltage across the lamp is enlarged by a factor of 1.5-10 by comparison with the first voltage, the current through the primary winding of the transformer being of such small dimension during the operation that the secondary winding of the ignition transformer acts as a filter inductor with the aid of a large part of its no-load inductance.