Patent ID: 6507596
Filing Date: 2003-01-14
Classification: H01S

Abstract:
A gas laser apparatus comprising:at least one pair of spaced main discharge electrodes forming a main discharge space therebetween, said pair of main discharge electrodes creating a discharge excitation by discharging a laser gas in said main discharge space; said gas laser apparatus having the laser gas to flow from outside the main discharge space into the main discharge space and then flow from inside the main discharge space to outside the main discharge space so that the laser gas circulates; and pre-ionization electrodes including at least one pair of dielectric pipes disposed asymmetrically with respect to a center of the main discharge space on a laser gas inflow side from which the laser gas flows into the main discharge space and a laser gas outflow side to which the laser gas flows from the main discharge space, for pre-ionizing the laser gas wherein the laser gas passing through the main discharge space flows at a speed so that a profile of laser beam output by the discharge excitation becomes symmetrical with respect to the center of a discharge width.