PRODUCTION METHOD FOR OPTICAL FIBER BASE MATERIAL

摘要

While a glass rod (2) for a core or a core and clad, inserted into a glass pipe (1) for a clad, is heated by a heater (3), the inside of the glass pipe (1) is depressurized. After at least one of the glass pipe (1) and the glass rod (2) is drawn, the pipe (1) and the rod (2) are integrated together, and then the both (1), (2) are drawn until the outer diameter of the pipe (1) is reduced to specified size.