Process for the production of a blank mold for glass fiber optical waveguides

US5160520A · kind A · utility

Assignee

• kabelmetal electro GmbH · DE

Inventors

• Norbert Keim · Besigheim, DE
• Manfred Wittmann · Rutzenmoos, AT

Key dates

• Filing date: Jun 21, 1991
• Grant date: Nov 3, 1992
• Expiry date: Jun 21, 2011

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C03B37/01869
• WIPO field: Other special machines
• WIPO sector: Mechanical engineering

Abstract

To produce a blank mold for glass fiber optical waveguides with a core and a single or multilayer sheath, in which the core glass material is applied to the inner wall of a glass tube by chemical deposition from the vapor phase, the internally-coated glass tube is caused to collapse by temperature treatment, and this blank mold is finally drawn out into a glass fiber, the temperature treatment for collapse is carried out along the glass tube in accordance with a temperature profile that is determined by an upper region of maximum glass temperature along the treated section of glass tube (hot zone) and a lower region at the glass softening temperature (soft zone). The region of maximum glass temperature shows a largely uniform temperature level with a width along the section of glass tube that is approximately equal to the width of the region at the glass softening temperature.