| 摘要 |
PURPOSE:To prevent overheat and damage of a component at the time of medium failure by providing a device for measuring transparency of coolant, a monitor means for generating an alarm signal when the measurement value exceeds an allowable value, and a means for displaying an alarm indicating failure of the medium. CONSTITUTION:High frequency voltage from a high frequency power source 3 is applied to between electrodes 2a, 2b provided on an outer wall of a discharge tube 1 to excite laser gas inside. A Fabry-PeGAMMA rot resonator is constituted of a rear mirror 6 with reflectivity of 99.5% and an output mirror 5 with reflectivity of 65% to amplify light emitted from laser gas molecules while a part of it is discharged outside as laser light 6 from the output mirror 5. Gas heated to high temperature by laser oscillation passes through heat exchangers 7a, 7b which are cooled by water, wherein a light emitting diode 11a and a transparency sensor 11 having a phototransistor 11b are provided via small windows 91b, 92b on the middle of a pipe 9b so that turbidity of water if any is displayed on a display unit 13. |
