| 摘要 |
PURPOSE:To obtain a laser beam having a good symmetrical characteristic and stable mode by making thick the width of metal electrodes and forming the end parts of their surfaces brought into contact with a discharge bulb of the metal electrodes as gradually curved surfaces. CONSTITUTION:Metal electrodes 2a, 2b form gradually curved areas 12a-12d at the end part of a discharge bulb 1 in its axial direction. Moreover, the metal electrodes 2a-2b also form gradually curved areas 13a-13d at the end part of the discharge bulb 1 in the circumferencial direction. The metal electrodes 2a, 2b are formed thick having sufficient thickness to form gradually curved areas 12a-13d, 13a-13d at the end part thereof. Accordingly, the field intensity at the end part of the metal electrodes 2a, 2b can be eased sufficiently and as a result, concentration of discharge is no longer generated and uniform high frequency discharge 10 can he obtained. Thereby, high performance laser beam, which is symmetrical about the oscillation axis and has good lateral mode, can be obtained. |
