Pulse injection starting for high intensity discharge metal halide lamps

摘要

A light source wherein a spiral line pulse generator, having an output coupled to one electrode of a metal halide discharge lamp and an input for coupling to a source of lamp operating power, provides high voltage, short duration lamp starting pulses. The spiral line pulse generator includes two conductors and two insulators, each in the form of an elongated sheet, in an alternating arrangement which is rolled together in a spiral configuration having a plurality of turns. The high voltage, short duration pulse is provided upon closure of a low inductance switch coupled between the conductors. A thermal switch can be utilized to bypass the spiral line pulse generator after lamp starting. The spiral line pulse generator can be enclosed within the lamp base of the light source.