Method for manufacturing a glass optical fiber preform
摘要
<p>A glass rod (2) for a core or for the core and a cladding is inserted into a glass pipe (1) for the cladding and heated by a heater (3) while the pressure inside the glass pipe (1) is reduced. After at least one of either the glass pipe (1) or the glass rod (2) is elongated, the glass pipe (1) and the glass rod (2) are formed into a single unit, and then the glass pipe (1) and the glass rod (2) are elongated until the outer diameter of the glass pipe (1) becomes a predetermined diameter. <IMAGE></p>
