Discharge-pumped gas laser with independent preionizing circuit

Abstract

A discharge-pumped gas laser, typically a discharge-pumped excimer laser, includes a main discharge circuit for producing an electric discharge in a laser gas to excite the laser gas for laser emission. The main discharge circuit comprises a first electric circuit having a thyratron, a charging circuit including a charging capacitor for storing an electric energy to operate the thyratron, and a discharging circuit including a pair of main discharge electrodes and a peaking capacitor for storing an electric energy to cause a main discharge in the laser gas between the main discharge electrodes. The laser gas is preionized by preionizers having a plurality of preionizing electrodes which produce an electric discharge to preionize the laser gas. The preionizing electrodes are connected in a second circuit which has a plurality of distributing capacitors for storing an electric energy to enable the preionizing electrodes to preionize the laser gas and supply substantially uniform electric currents to the preionizing electrodes. The distributing capacitors have substantially the same capacitances. The first and second electric circuits are substantially independent of each other.