Joseph Adam Fletcher

US Patent:

20040107735, Jun 10, 2004

Filed:

Dec 4, 2002

Appl. No.:

10/309852

Inventors:

Joseph Fletcher - Marietta GA, US
Thomas Miller - Alpharetta GA, US
John Rennell - Suwanee GA, US
Don Smith - Atlanta GA, US
Peter Bauer - Mainhausen, DE
Norbert Cibis - Kahl/Main, DE
Ralph Sattmann - Aschaffenburg, DE
Rene Sowa - Pouch, DE

Assignee:

Fitel USA Corp.

International Classification:

C03B037/028

US Classification:

065/412000

Abstract:

An optical fiber preform includes a core rod and an overclad tube having an open, distal end dimensioned to enter the mouth of a vertical fiber draw furnace. A plug is fixed in the region of the distal end of the tube, and the core rod is disposed axially inside the overclad tube so that a distal end of the rod is restrained from downward movement by the plug as the tube enters and descends into a hot zone of the draw furnace. The distal end of the tube is heated in the furnace hot zone until the tube and the plug soften and fuse with one another. The tube then collapses onto the core rod to produce a drop from which an optical fiber having desired properties may be drawn.

US Patent:

20040144133, Jul 29, 2004

Filed:

Jan 23, 2003

Appl. No.:

10/349816

Inventors:

Joseph Fletcher - Marietta GA, US
Thomas Miller - Alpharetta GA, US
Donovan Guthrie - Lawrenceville GA, US

International Classification:

C03B037/15

US Classification:

065/391000, 065/057000, 065/407000

Abstract:

A method of assembling two optical fiber tube preforms end-to-end without negatively impacting the local glass chemistry at the joint. The ends of two tubes to be joined together are reverse-tapered by a grinding such that the outside portion of the tube walls extend further outward than the inner portions of the tube walls. Two tubes having such ends are briefly heated and brought together, and the reverse taper minimizes the size of the cross-sectional area of the tube portions to be joined. A minimal amount of heat that does not significantly impact the glass chemistry at the joint is applied to the outside of the tubes to effect a tack weld that joins the tubes. Once the tack weld is in place, additional heat in combination with a vacuum force can be applied to the tubes, which completes the sealing of the weld.

US Patent:

20050064188, Mar 24, 2005

Filed:

Sep 19, 2003

Appl. No.:

10/665623

Inventors:

Joseph Fletcher - Marietta GA, US
Andrew Jones - Dacula GA, US
Thomas Miller - Alpharetta GA, US
Don Smith - Decatur GA, US
Shunhe Xiong - Alpharetta GA, US

International Classification:

D02G003/00

US Classification:

428375000

Abstract:

Embodiments of the invention include an optical fiber preform assembly and a method for making optical fiber using the preform assembly. The assembly includes a preform core rod, at least one overclad tube formed around the preform core rod, a handle attached to one end of the overclad tube, and a refractory material positioned in the overclad tube between the preform core rod and the handle. The refractory material reduces if not prevents movement of the preform core rod into the handle during the fiber draw process. Preferably, the refractory material is made of, e.g., magnesium oxide and/or aluminum oxide, and has a melting point, e.g., greater than approximately 2000 degrees Celsius. Embodiments of the invention also include a method for making optical fiber using this preform assembly.

US Patent:

20060216527, Sep 28, 2006

Filed:

Mar 23, 2005

Appl. No.:

11/088076

Inventors:

Joseph Fletcher - Marietta GA, US

International Classification:

C03B 37/028
B32B 17/06

US Classification:

428432000, 065412000, 428426000

Abstract:

An optical fiber preform is assembled by inserting core rod segments axially end to end inside of a first glass overclad tube having a first, relatively low concentration of a given impurity that contributes to signal attenuation in an optical fiber to be drawn from the preform. The first overclad tube with the contained core rod segments are inserted in a second glass tube having a second concentration of the given impurity which is higher than the first concentration. The wall thickness of the first overclad tube is preferably less than that of the second overclad tube, thus reducing the amount of high purity glass needed to form the first overclad tube and attendant manufacturing costs. The core rod segments may include salvageable remnants from a single long core rod produced, for example, by vapor axial deposition (VAD).

US Patent:

20080087303, Apr 17, 2008

Filed:

Oct 17, 2006

Appl. No.:

11/582168

Inventors:

Joseph P. Fletcher - Marietta GA, US
Lazhar Mazlout - Duluth GA, US
Michael Pate - Senoia GA, US

International Classification:

B08B 3/00

US Classification:

134 26

Abstract:

Core rods or other glass components associated with optical fiber preforms are cleaned by loading them into a number of first sleeves, and partially obstructing entrance and exit ends of the sleeves to retain the components. The sleeves are contained inside a second sleeve so that the entrance ends of the first sleeves face an entrance end of the second sleeve. A fluid delivery system supplies cleaning fluids to the entrance end of the second sleeve, so that the fluids enter the first sleeves and contact exposed surfaces of the loaded components. The fluids leave the exit ends of the first sleeves and purge from an exit end of the second sleeve. Separators may be placed between the components in the first sleeves to enhance cleaning action and to cushion adjacent end faces of the components. Cleaned components may be unloaded from the first sleeves without risk of contamination.