| 摘要 |
A optical-fiber preform is produced by the stages of: heating a fine grain body of glass having major component SiO2 at high temp. in a vacuum, impregnating one or more gas of SiF4, SF6, CF6, C2F6, C3F8, CCl2F4 and COF2 in the body at above atmospheric pressure and vitrifying the body by heating and sintering at the higher temp. in below atmospheric pressure. The preform has vol. density of at least 0.4g/cm3. |
