Patent · US Expired

Method for producing glass preform for optical fiber

US4693738A · kind A · utility

11Cited by
3References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 30, 1985
Grant dateSep 15, 1987
Priority date
Expiry dateSep 30, 2005

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S65/16
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

An optical fiber comprising a core essentially made of quartz and a cladding made of fluorine added quartz is fabricated with good productivity from a glass preform produced by a method comprising maintaining a hollow cylindrical porous glass preform in a first high temperature atmosphere comprising at least one fluorine-containing compound with jetting a cooling gas through the central hollow part of the porous glass preform to grade the amount of fluorine to be added in the radial direction of the porous glass preform and then sintering the porous glass preform in a second high temperature atmosphere kept at a temperature higher than the first high temperature atmosphere to make it transparent.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.