COMPACT EXCIMER LASER INSULATOR WITH INTEGRAL PRE-IONIZER

摘要

A pre-ionizing system in which the pre-ionizer elements are integral with the cathode insulating plate (501) is provided. The cathode insulating plate (501) includes a recessed region machined into the front surface into which the cathode (106) fits, lying substantially flush with the insulator front surface. The back surface of the insulating plate (501) contains a pair of slots running parallel to the long axis of the cathode (106). The pre-ionizing rods (305) are located within these slots, the slots having sufficient depth to locate the rods (305) approximately adjacent to the cathode (106). By maintaining the rods at ground, a capacitor is formed in which the insulating plate (501) material between the rod (305) and the cathode (106) acts as the dielectric material of the capacitor. When a voltage pulse is applied, a capactive corona discharge is formed which pre-ionizes the gases in the region near the electrode.