| 摘要 |
PURPOSE:To improve structural accuracy by forming a multi-structured glass fiber matrix-constituting material with a glass rod for core, a glass tube for clad and a glass tube for jacket and drawing with heating. CONSTITUTION:An oxide glass matrix containing 50-85wt.% PbO having a refractive index giving about zero photoelastic constant as glass for core is prepared. Next, matrices as glass for clad and jacket are prepared so as to have same basic composition as the glass for core and have a smaller refractive index for clad and a larger refractive index for jacket in regard to the glass for core. Thereafter, every matrices are subjected to cutting process and a second glass tube of a matrix for clad is arranged in a first glass tube of a matrix for jacket, then a glass rod of a matrix for core is arranged in the second glass tube, thus a glass fiber matrix-constituting material having a dense three-layered structure is formed. Said material is melted in heating and drawn, then subjected to coating treatment to afford glass fiber having high structural accuracy. |
