Western Electric Company, Inc.

At&t Technologies, Inc.

Bell Telephone Laboratories

Western Electric Inc.

Matthew J Andrejco

Eugene Potkay

John Burnette MacChesney

Un C Paek

Charles M Schroeder, Jr

A technique for fabricating a lightguide soot-boule. Gaseous reactants are directed through an inner tube of a torch having a plurality of coaxially aligned tubes. A glassy soot is formed at the output of the torch by a flame hydrolysis reaction and at least a portion of the soot is deposited on a forming soot-boule. The inner tube may be axially moved during the soot deposition process to alter or maintain the refractive index of the boule.

Method of fabricating a lightguide fiber

A high frequency induction furnace (10) for reflowing a portion of a lightguide preform (44) in order to draw a fiber (52) therefrom. The furnace (10) has a centrally located tubular susceptor (34) therein having a thin coating of the preform material (e.g., silica) on at least a portion of the inside surface thereof. A cylinder (62) is positioned in concentric, spaced relation about the susceptor (34) and is surrounded by an insulating grain (36). A high frequency coil (38) is energized to couple its electromagnetic field to the susceptor (34) to heat and reflow a portion of the preform (44) in order to draw the fiber (52) therefrom. The thin coating prevents contaminating particulates from migrating from small cracks in the inside surface of the susceptor (34) onto the preform (44) while the cylinder (62) prevents small particulate emanating from the insulating grain (36) from being drawn through larger cracks in the susceptor and onto the preform and/or the fiber 52.

Zirconia induction furnace

A vapor-phase axial deposition system (5) for fabricating a lightguide soot boule (16). The system (5) is comprised of a short cylindrical housing (10) having end plates (26--26) affixed thereto. A starting member (58) is radially directed into the central portion of the housing (10) and a torch (12) is activated to direct a stream of glassy soot thereat. The member (58) is simultaneously rotated and withdrawn from the housing (10) as a cylindrical, porous, soot boule is formed on the end thereof. The housing (10) having a substantially two-dimensional character eliminates secondary gas flow within the housing (10) resulting in enhanced deposition rates and repeatability.

Vapor-phase axial deposition system

A reactant deposition torch (10) has a plurality of concentric glass tubes (16, 18, 20, 24 and 26). Various gases pass through the tubes (18, 20, 24 and 26) while particle producing reactants pass through the inner tube (16). The concentricity of the tubes is accurately maintained by a plurality of precision machined splines located on the outer periphery of the inner and intermediate tubes (16, 18, 20 and 24). Additionally, the inner tube (16) is movable in the axial direction during the deposition process to controllably alter the amount of reactant to be deposited.

Vapor-phase axial deposition torch

A method of practicing the MCVD process is disclosed. In the inventive process, the core deposition is completed prior to completion of the cladding. An intermediate preform structure with a core-to-clad ratio greater than that desired in the ultimate fiber is consequently obtained. Subsequent to internal core deposition, additional material is added externally to complete the cladding thereby yielding an optical fiber preform with the desired core-to-clad ratio.

Growing community of inventors

North Hanover Township, Burlington County, NJ, United States of America

Matthew J Andrejco