| 摘要 |
PURPOSE:To use X-rays efficiently by mounting several pairs of main discharge electrodes along the circumferential direction in a laser tube and installing an X-ray tube to a hollow section corresponding to the doughnut-shaped core section of the laser tube. CONSTITUTION:A laser tube 20 having a doughnut-shaped cross section, several pairs of main discharge electrodes 21, 22 mounted in the circumferential direction in the laser tube, an X-ray tube 30 installed to a hollow section corresponding to the doughnut-shaped core section of the laser tube 20, and optical resonators 23 set up to each main discharge electrode pair respectively are provided. Consequently, the main discharge spaces in the laser tube 20 are pre-ionized by radially projected X-rays. Accordingly, laser oscillation is conducted from a plurality of spaces, long pulses and high repetition can be attained and the several pairs of main discharge electrodes 21, 22 are arranged in a circulating flow path, thus reducing the flow rate of gas by a factor 4 for four pairs of the main discharge electrodes and miniaturizing a circulator. X-rays are pre-ionized in multi-directions as compared with a prior art where pre-ionization is carried out only in one direction of X-rays, thus improving the utilization of X-rays. |
