Process of drawing optical fiber
AssigneeSumitomo Electric Industries, Ltd.
InventorsYuichi Ohga, Shinji Ishikawa, Hiroo Kanamori, Ichiro Yoshimura, Horoshi Yokota
Life of this patent
Estimating the term…
Abstract
There is provided a process of melt drawing an optical fiber from a preform therefor in which a heating furnace comprising a muffle tube inside thereof through which the optical fiber is passed is provided immediately below a melt drawing furnace to further draw the optical fiber while heated, and an interior of the muffle tube is kept in an atmosphere selected from the group consisting of an inert atmosphere, an atmosphere comprising oxygen gas and an atmosphere comprising hydrogen gas.
Claims3
A process of drawing an optical glass fiber from a quartz based preform comprising the steps of:
- i) heating the preform in a series of furnaces including at least a drawing furnace and a heating furnace which is immediately below the drawing furnace, the heating furnace which is kept at a temperature in the range of from 500.degree. C. to 1500.degree. C. and contains a muffle tube having an atmosphere consisting essentially of hydrogen gas;
- and
- ii) drawing the optical glass fiber such that said fiber passes through the drawing furnace and the heating furnace which contains the muffle tube, wherein the fiber immediately before entering the heating furnace has a temperature in the range of from 500.degree. to 1500.degree. C. and has a residence time within the heating furnace in the range of from 0.1 to 10 seconds.
Dependencies are inferred from the claim text.