High pressure lamp with lamp flicker suppression and lamp voltage control

Abstract

A method and system to supply current to a high pressure lamp is provided, the method and system comprising an alternating lamp current waveform with a half cycle mean amplitude Iand a half cycle time duration T, a current pulse waveform including at least one current pulse with a half cycle mean amplitude Iand at least one current pulse occurring after the trailing edge of a half cycle of the alternating lamp current, the pulse having a half cycle duration of Tp. These waveforms are combined to generate a current waveform including a current pulse waveform, the current pulse waveform starting after a time delay Td from the trailing edge of a half cycle of the alternating lamp current waveform, the time duration Tp of the at least one current pulse lasting less than the remaining time before the leading edge of the second half cycle of the alternating lamp current waveform. The combined current waveform supplies current to a high pressure lamp and produces a cone shaped tip protrusion which reduces lamp flicker.