| 摘要 |
PURPOSE:To make it possible to monitor the state of plasma accurately, by detecting fluorescence excited by laser from a specified chemical species and light emission from one or more other chemical species in the plasma. CONSTITUTION:Laser light 6 having a specified wavelength from a variable wavelength laser generator 1 is projected into a plasma generating source 5. Fluorescence 8 is emitted from the excited specified chemicals species A in the direction perpendicular to the output direction of the laser light 6. The fluorescence 8 is emitted accompanied by the formation of the plasma. Light emission 7 is caused by a specified chemical species B representing the plasma state. The fluorescence 8 and the light 7 are received by a light receiving scanning mechanism 14, which is in parallel with the outputting direction of the laser light 6 and can be moved up and down and right and left. The intensities of the received light beams are measured by light detectors 11 and 12. Based on the results, an operator 13 performs monitoring operation. When the intensities of the light beams are changed and the ratio or the difference between the intensities of the light beams are changed, the operator 13 obtains the state of each light beam. Thus the monitoring can be performed. |
