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 I1 and a half cycle time duration T, a current pulse waveform including at least one current pulse with a half cycle mean amplitude I2 and 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.

Abstract: In a lamp lighting ballast which generates a lamp lighting signal for a lamp, provided is a striation elimination circuit to increase the lumen output frequency for elimination of visual striations which may occur within the lamp. An even harmonic signal generator is configured to generate an even harmonic waveform, and an injection point is configured to receive the even harmonic signal into the lamp lighting system. The injection point is located at a location wherein the even harmonic signal alters the lamp lighting signal from a symmetric signal configuration to a high content even harmonic signal configuration prior to being received by the lamp.