US 6,769,275 B2 · Method for making optical fiber preform using simultaneous inside and outside deposition

Abstract

A method and apparatus for making optical fiber preforms using simultaneous plasma deposition on the inside and outside surface of a starting tube. A starting tubular member is rotated, CFOT chemicals are selectively injected into the plasma torch, and CFIT chemicals are selectively injected to flow through the hollow of the tube. The plasma torch is traversed along the tubular member to simultaneously deposit soot on the inside and outside surface. The soot on one or both surfaces may be consolidated into a silica layer as it is deposited. The plasma torch is traversed again to deposit additional soot, and/or consolidate previously deposited soot, on one or both surfaces. The process is repeated until a predetermined amount of silica is formed on the tubular member. The tubular member is then collapsed. Optionally, additional plasma deposition is performed during or after the collapsing.

Claims22

Dependent claims

A method for making an optical fiber preform, comprising steps of:

(a) providing a tubular member having a center axis, a cylindrical void, an inner surface surrounding the void, and an outer surface, the inner surface and outer surface coaxial with one another about the center axis;
(b) simultaneously depositing an outer silica soot layer on the outer surface and consolidating the outer silica soot layer into a vitreous silica layer and depositing an inner soot layer on the inner surface and consolidating the inner soot layer into a vitreous silica layer;
(c) depositing a second outer silica soot layer on the outer surface of the previously deposited outer vitreous silica layer;
(d) simultaneously depositing an outer silica soot layer on the outer surface of the second outer silica soot layer and consolidating said outer silica soot layer and said second outer soot layer into a vitreous silica layer and depositing an inner soot layer on the inner surface and consolidating the inner soot layer into a vitreous silica layer;
and
(e) repeating steps (c) and (d) until a predetermined thickness of said vitreous silica layers are formed.

3 more elements

A method for making an optical fiber preform, comprising steps of:

(a) providing a tubular member having a center axis, a cylindrical void, an inner surface surrounding the void, and an outer surface, the inner surface and outer surface coaxial with one another about the center axis;
(b) simultaneously depositing an outer silica soot layer on the outer surface and consolidating the outer silica soot layer into a vitreous silica layer and depositing an inner soot layer on the inner surface and consolidating the inner soot layer into a vitreous silica layer;
(c) depositing a second outer silica soot layer on the outer surface of the previously deposited outer vitreous silica layer concurrent with depositing a second silica soot layer on the inner surface;
(d) simultaneously depositing an outer silica soot layer on the outer surface of the second outer silica soot layer and consolidating outer silica soot layer and said second outer soot layer into a vitreous silica layer and depositing an inner soot layer on the inner surface and consolidating the inner soot layer and the second inner soot layer into a vitreous silica layer;
and
(e) repeating steps (c) and (d) until a predetermined thickness of said vitreous silica layers are formed.

3 more elements

A method for making an optical fiber preform, comprising steps of:

(a) providing a tubular member having a center axis, a cylindrical void, an inner surface surrounding the void, and an outer surface, the inner surface and outer surface coaxial with one another about the center axis;
(b) simultaneously depositing an outer silica soot layer on the outer surface and depositing an inner soot layer;
(c) simultaneously consolidating the outer silica soot layer into a vitreous silica layer, the outer surface of said vitreous silica layer becoming the outer surface of said tubular member, and the inner silica soot layer into a vitreous silica layer and
(d) repeating steps (b) and (c) until a predetermined thickness of said vitreous silica layers are formed.

1 more element

A method for making an optical fiber preform, comprising steps of:

(a) providing a tubular member having a center axis, a cylindrical void, an inner surface surrounding the void, and an outer surface, the inner surface and outer surface coaxial with one another about the center axis;
(b) simultaneously depositing an outer silica soot layer on the outer surface and depositing an inner soot layer of substantially pure silica soot on the inner surface;
(c) simultaneously depositing a second outer silica soot layer on the outer surface of the previously deposited outer silica soot layer and consolidating the outer silica soot layer and said second outer soot layer into a vitreous silica layer, the outer surface of said vitreous silica layer becoming the outer surface of said tubular member, and depositing dopants onto said inner soot layer and consolidating the inner soot layer and the dopants into a vitreous silica layer doped in accordance with said dopants;
and
(d) repeating steps (b) and (c) until a predetermined thickness of said vitreous silica layers are formed.

2 more elements

Dependencies are inferred from the claim text.

Method for making optical fiber preform using simultaneous inside and outside deposition

Life of this patent

Method for making optical fiber preform using simultaneous inside and outside deposition

Life of this patent

Abstract

Claims22