Patent · US Expired

Method for producing core/clad glass optical fiber preforms using hot isostatic pressing

US5735927A · kind A · utility

22Cited by
3References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 28, 1996
Grant dateApr 7, 1998
Priority date
Expiry dateJun 28, 2016

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC03B2201/86
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

Core/clad glass optical fiber preforms free of bubbles and soot at the coclad interface are fabricated by inserting a glass core rod into a cladding glass tube sized so that space remains between them, sealing the top and bottom of the tube onto the core rod to form a sealed space between them which is relatively soot free and under a vacuum and then hot isostatically pressing the sealed composite to collapse the tube onto the rod and also collapse bubbles in the glass. Soot formation is avoided or minimized by purging the space with inert gas while the bottom of the tube is collapsed onto the rod and by sealing the top under a dynamic vacuum and at the lowest possible temperature to avoid soot formation without cracking the glass. The space is vacuum outgassed before the second seal is made. Chalcogenide fiber drawn from a preform made in this fashion exhibits very low transmission losses.

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