Method for producing an optical preform with a POD cladding glass layer

US9296639B2 · kind B2 · utility

Assignee

• HERAEUS QUARZGLAS GMBH & CO. KG · DE

Inventors

• Gerhard Schoetz · Aschaffenburg, DE
• Karsten Bräuer · Bruchköbel, DE
• Richard Schmidt · Hammersbach, DE
• Peter Bauer · Siegburg, DE
• Andreas Schultheis · Langenselbold, DE
• Paul Bödiger · Rodenbach, DE
• Andreas Langner · Alzenau, DE

Key dates

• Filing date: Aug 8, 2013
• Grant date: Mar 29, 2016
• Expiry date: Aug 8, 2033

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C03B2203/12
• WIPO field: Other special machines
• WIPO sector: Mechanical engineering

Abstract

The invention relates to a plasma deposition process for producing an optical preform, which is characterized by a cladding glass layer having a non-round internal cross-section together with high fluorine doping and axially and radially specified dopant distribution, which in the simplest case is as uniform as possible. For this purpose, a two-stage method is proposed, wherein a substrate body having a non-round cross-section is first reshaped into a coated substrate body having a circular cross-section in that a POD filling layer made of quartz glass having the nominal fluorine concentration is deposited onto a present filling surface and rounded by grinding, and then in the second stage of the method a POD sheathing glass layer made of fluorine-doped quartz glass and having a circular-ring-shaped cross-section is deposited.