| 摘要 |
PURPOSE:To manufacture an optical fiber having a property of highly retaining the polarization surface by covering core glass obtd. by uniting >=2 kinds of glass with clad glass having a refractive index lower than that of the core glass. CONSTITUTION:A container 1 provided with a circular hole at the bottom and divided into 4 sections by partition plates which intersect at the central axis of the hole at 45 deg. angle is placed in a container 2 provided with a circular hole at the bottom so as to allow the central axes of the holes to coincide with each other. Molten glass consisting of about 86mol% SiO2, about 4% GeO2 and about 10% P2O5 is charged into the sections of the container 1 having 45 deg. angle, and molten glass consisting of about 87% SiO2, about 3% GeO2 and about 10% P2O5 is charged into the other sections. They are simultaneously drawn to obtain core glass composed of 2 parts 4 with a higher refractive index and 2 parts 5 with a lower refractive index. Molten glass consisting of about 90% SiO2 and about 10% P2O5 is charged into the container 2 and drawn while continuously covering the core glass. |
