| 摘要 |
PURPOSE:To prepare a parent material for high-quality optical fiber efficiently, by spraying the inner wall of quartz pipe with a raw material solution (dispersion of fine powder of glass), drying it, depositing and piling successively fine powder layer of glass material. CONSTITUTION:A dispersion medium is put in the raw material tank 1, and fine powder of glass having the desired refractive indexes in the raw material tanks 2-1-2-n, respectively. The dispersion medium 3 and the fine powder of glass 4-1 are then sent to the blending tank 9 to give a raw material solution. The raw material solution is sent to the inner pipes of the branched pipes 10-1-10-m, and an inert gas such as Ar, etc., to the outer pipes. The raw material solution is jetted from the nozzles 13-1-13-m to the quartz pipes 14-1-14-m transferred in the shaft direction by the traveling devices 15-1-15-m, attached the inner walls of the pipes, the dispersion medium 3 is evaporated by the electric furnaces 16-1-16-m, to form the fine powder layer of glass 17-1-17- m on the inner walls of the quartz pipes. As the fine powder of glass is successively changed from 4-2-4-n, the above-mentioned operations are repeated, the desired fine powder layers of glass are piled on the inner wall of quartz glass pipes, and it is subjected to glass formation treatment, and collapsing treatment, to give a parent material. |
