| 摘要 |
PURPOSE:To efficiently deposit a uniform glass layer at a proper vitrifying temp. by installing a glass transparency measuring system interlocking with a heating means and a radiation pyrometer detecting the temp. of an outer wall at a vitrifying part so as to control the heating temp. CONSTITUTION:Gaseous starting material A is introduced into a transparent glass tube 1 from the arrow B direction. The tube 1 is locally heated with a heating means 2 mounted on a moving stand 3 moving in the longitudinal direction of the tube 1 to chemically react the gaseous material A in a vapor phase, and the reaction product deposited on the inner wall of the tube 1 is vitrified. Laser beams from a laser device 7 are passed through the tube 1 perpendicularly to the axis of the tube 1 through a reflecting mirror 4, and the beams are made incident to a photodetector 5 and subjected to photoelectric conversion. A signal corresponding to the detected output is fed to a flow rate controller 8. On the other hand, a slight change in the heating temp. of the tube 1 is measured with a radiation pyrometer 6, and a signal corresponding to the detected signal is fed to the controller 8 to control the flow rates of gases for the heating means 2 with mass flow meters 9, 10. |
