US Patent 9905399 Carbon spark evaporation

The invention relates to a method for operating a pulsed discontinuous spark discharge. The spark is fed via a capacitor. Between the pulses there are switched-off time intervals during which no spark current flows. Within the pulses, that is to say during the switched-on time intervals, the supply of charge is stopped upon a current threshold being reached and is restarted, with the result that subpulses occur within the pulses. The time intervals and subpulses are chosen according to the invention such that when the capacitor is switched on again, the spark discharge readily ignites again.