Patent ID: 7782922

Claim:
A narrow-band discharge excited laser device comprising: a laser chamber having a laser gas sealed therein, a pair of electrodes provided therein, the pair of electrodes facing each other with a predetermined inter-electrode distance therebetween, and the pair of electrodes each having a width of 1 mm to 2 mm, and a cross-flow fan for circulating the laser gas passing between the pair of electrodes; a high-voltage power supply connected to the pair of electrodes; and a band-narrowing module having a magnifying prism, a slit, and a grating; wherein the band-narrowing module receives laser light generated by the laser chamber that passes through the slit, wherein the high-voltage power supply applies a pulsed voltage to the pair of electrodes to generate electric discharge between the electrodes, and wherein a ratio between the width of each of the pair of electrodes and the predetermined inter-electrode distance (electrode width/inter-electrode distance) is 0.25 to 0.125.