| 摘要 |
PURPOSE:To prepare glass fibers for light transmission having a stepped refractive index distribution, by changing over the low-temperature depositing step after the stuffing in the molecular stuffing method to a slow depositing step at a high temperature. CONSTITUTION:A porous glass rod is immersed in a stuffing solution containing a nitrate compound, e.g. CsNO3, as a dopant compound and then immersed in propanol at 97 deg.C to replace the water in the micropores with the propanol. The glass rod is then dried in vacuo to evaporate the alcohol and decompose the nitrate compound described above, and a glass rod of high refractive index is obtained. A clad part of low refractive index is formed around the glass rod as a core glass, and melt spun to give glass fibers. Thus, glass fibers for optical communication having a large number of openings and a refractive index distribution of the stepped type or close thereto can be prepared. |
