METHODS OF CONTROLLING THE BRIGHTNESS OF A GLOW DISCHARGE

摘要

Methods of controlling the brightness of a glow discharge which switches from a low brightness state to a high brightness state a given time after the start of an excitation pulse are described. In the first method, conventional pulse duration modulation produces a dimming ratio much greater than the ratio of duty factor variation. In the second method, a plurality of sets of pulses having different fixed durations but variable repetition rates are employed. In the third method, a plurality of sets of pulses having different relative durations have their pulse durations modulated in synchrony.