Production of base material for optical fiber

Abstract

Abstract PURPOSE:When a base material for optical fiber is prepared by the VAD method, the content of P2O5 is controlled in a certain range in the growing porous base material and the material is made clear by passing it through the high-temperature furnace at a high speed to give a base material for optical fiber of low transmission loss. CONSTITUTION:Glass starting materials such as SiCl4, GeCl4, POCl3 are blown out of the burner together with gases of H2, O2, Ar, etc. to form fine particles of glass in the flame, allow them to deposit on the top of the rotating quartz rod and to grow in the roating shaft direction whereby a porous base material containing 0.05-5wt% P2O5 is formed. Then, the porous base material is passed through a furnace heated over 1,700 deg.C at a speed of 2-20mm./min for clarification. Thus, P2O5 is considerably evaporated off, while GeO2 remains almost without vaporization to give the objective base material for optical fiber of reduced transmission loss at a wave length of 1.55mum.

Inventors

• 👤 Minoru Watanabe
• 👤 稔 渡辺
• 👤 Tsunehisa Kyodo
• 👤 倫久 京藤
• 👤 Nobuo Inagaki
• 👤 稲垣　伸夫

Bibliographic Details