| 摘要 |
PURPOSE:To hold a laser output constant by selectively passing oxygen in the atmosphere to a recirculation system of a laser oscillation medium through oxygen transmitting means. CONSTITUTION:A laser oscillation medium is sucked from an oscillation tube 1 through an upstream side conduit 3, and recirculated to the tube 1 by the pressure of a circulation pump 4. An O<2> regulating valve (CV) 9 which is opened or closed by a signal from a laser output detector (LS) 8 provided in the tube 1 is interposed between the conduit 3 of the upstream side directly above the pump 4 and oxygen transmitting means 7. When the valve 9 is opened, the O2 in the atmosphere is selectively transmitted to the conduit 3 through the means 7. An O2 increasing film for selectively passing oxygen only to the means 7 is employed, and suitable O2 is transmitted into the conduit 3 through the O2 increasing film due to the pressure difference between the pressure in the conduit 3 of the upstream side of the pump 4 and the atmospheric pressure. |
