| 摘要 |
PURPOSE:To avoid breakages of discharge tubes themselves that are caused by elevated temperatures at the center of each discharge tube by combining a plurality of discharge tubes through a junction electrode and by forming multistage discharge regions in the direction of laser beam axis with the arrangement of the electrodes and the junction electrode which are prepared at both ends of the combined discharge tubes. CONSTITUTION:Two discharge tubes 5 are used and these tubes 5 and 5 are connected by a junction electrode 18. An electric charge electrified to a capacitor 13, therefore, flows through both electric discharge circuits located between an electrode 6a and the junction electrode 18 as well as the electrode 6b and the junction electrode 18 at the same time. In other words, two discharge circuits are in a state where they are connected to the capacitor 13 in parallel and then, two discharge regions are connected in series. In this way, as the discharge tubes 5 are divided into two and two tubes are connected by the junction electrode 18, a laser oscillator functions as if one discharge tube is placed between the electrodes 6a and 6b and yet, being different from the case of a single unit of the discharge tube, a temperature distribution on an optical axis is alleviated as a whole. |
