Rostislav R Khrapko

US Patent:

7524780, Apr 28, 2009

Filed:

Jan 28, 2005

Appl. No.:

11/046435

Inventors:

Laura J. Ball - Corning NY, US
Bruno P. M. Baney - Seyssins, FR
Dana C. Bookbinder - Corning NY, US
Keith L. House - Corning NY, US
Rostislav R. Khrapko - Corning NY, US
Lisa A. Moore - Corning NY, US
Susan L. Schiefelbein - Ithaca NY, US

Assignee:

Corning Incorporated - Corning NY

International Classification:

C03C 13/04
C03C 3/076
C03C 3/06

US Classification:

501 37, 501 54, 501 55, 501 56, 385123, 385141, 385142, 385144

Abstract:

A method of forming an alkali metal oxide-doped optical fiber by diffusing an alkali metal into a surface of a glass article is disclosed. The silica glass article may be in the form of a tube or a rod, or a collection of tubes or rods. The silica glass article containing the alkali metal, and impurities that may have been unintentionally diffused into the glass article, is etched to a depth sufficient to remove the impurities. The silica glass article may be further processed to form a complete optical fiber preform. The preform, when drawn into an optical fiber, exhibits a low attenuation.

US Patent:

7536076, May 19, 2009

Filed:

May 10, 2007

Appl. No.:

11/801472

Inventors:

Rostislav Radievich Khrapko - Corning NY, US

Assignee:

Corning Incorporated - Corning NY

International Classification:

G02B 6/00

US Classification:

385142, 385141

Abstract:

Disclosed is an optical fiber having a silica-based core comprising an alkali metal oxide selected from the group consisting of KO, NaO, LiO, RbO, CsO and mixtures thereof in an average concentration in said core between about 50 and 500 ppm by weight, said core further comprising chlorine and fluorine, wherein the average concentration of fluorine in said core is greater than the average concentration of alkali metal oxide in said core and the average concentration of chlorine in said core is greater than the average concentration of alkali metal oxide in said core; and a silica-based cladding surrounding and directly adjacent the core. By appropriately selecting the concentration of alkali metal oxide dopant in the core and the cladding, a low loss optical fiber may be obtained.

US Patent:

7929818, Apr 19, 2011

Filed:

Jun 30, 2010

Appl. No.:

12/827333

Inventors:

Scott Robertson Bickham - Corning NY, US
Rostislav Radievich Khrapko - Corning NY, US
Snigdharaj Kumar Mishra - Wilmington NC, US

Assignee:

Corning Incorporated - Corning NY

International Classification:

G02B 6/028

US Classification:

385124

Abstract:

According to some embodiments an optical waveguide fiber comprises (i) a Ge free core having an effective area of 100 μmto 150 μm, at 1550 nm wavelength, said core comprising: a) a central core region extending radially outwardly from a centerline to a radius r, and having a relative refractive index percent profile Δ(r) in % measured relative to pure silica, wherein −0. 1%≦Δ(r)≦0. 12%, wherein the central core region has a maximum relative refractive index percent, Δ; (b) a first annular core region surrounding and directly adjacent to the central core region, having an α value 1. 5≦α≦10, and extending to an outer radius r, wherein 6 μm≦r≦10 μm, and having a relative refractive index percent profile, Δ(r) in % measured relative to pure silica, a minimum relative refractive index Δ, a maximum relative refractive index Δand the relative refractive index measured at a radius r=2 μm, wherein 0. 45≦Δ≦0; −0. 25≧Δ≧−0.

US Patent:

8012894, Sep 6, 2011

Filed:

May 5, 2008

Appl. No.:

12/151172

Inventors:

Dana Craig Bookbinder - Corning NY, US
Richard Michael Fiacco - Corning NY, US
Kenneth Edward Hrdina - Horseheads NY, US
Rostislav Radievich Khrapko - Corning NY, US

Assignee:

Corning Incorporated - Corning NY

International Classification:

C03C 3/06
C03B 19/06
C03B 19/00
C03B 37/00
C03B 37/018

US Classification:

501 54, 65 174, 65 176, 65 321, 65413, 65421, 65422

Abstract:

A fused silica glass and a fused silica article having a combined concentration of at least one of OH and OD of up to about 50 ppm. The fused silica glass is formed by drying a fused silica soot blank or preform in an inert atmosphere containing a drying agent, followed by removal of residual drying agent from the dried soot blank by heating the dried soot blank in an atmosphere comprising an inert gas and of oxygen.

US Patent:

8062986, Nov 22, 2011

Filed:

Jul 27, 2007

Appl. No.:

11/881599

Inventors:

Rostislav Radievich Khrapko - Corning NY, US
Nicolas LeBlond - Painted Post NY, US
James Edward Tingley - Swain NY, US

Assignee:

Corning Incorporated - Corning NY

International Classification:

C03C 3/06
C03B 19/06
C03B 19/00

US Classification:

501 54, 65 174, 65 176

Abstract:

A fused silica article having a combined concentration of hydroxyl (OH) and deuteroxyl (OD) concentration of less than 10 parts per million (ppm) and, in one embodiment, less than 1 ppm. The fused silica article is formed by drying a soot blank in a halogen-free atmosphere comprising carbon monoxide. The dried soot blank may optionally be doped to reach target levels of OH and OD concentrations and improve homogeneity within the fused silica article. The dried soot blank is then oxidized and, sintered to form the article. A method of reducing the combined concentration of OH and OD to less than 10 ppm is also described.

US Patent:

8268740, Sep 18, 2012

Filed:

Feb 2, 2009

Appl. No.:

12/364083

Inventors:

Richard Michael Fiacco - Corning NY, US
Kenneth Edward Hrdina - Horseheads NY, US
Rostislav Radievich Khrapko - Corning NY, US
Lisa Anne Moore - Corning NY, US
Charlene Marie Smith - Corning NY, US

Assignee:

Corning Incorporated - Corning NY

International Classification:

C03C 3/06
C03B 37/018
C03B 37/01

US Classification:

501 54, 65414, 65422, 65426

Abstract:

A fused silica glass having a refractive index homogeneity of less or equal to about 5 ppm over an aperture area of at least about 50 cm. The fused silica glass is also substantially free of halogens and has an adsorption edge of less than about 160 nm. The glass is dried by exposing a silica soot blank to carbon monoxide before consolidation, reducing the combined concentration of hydroxyl (i. e. , OH, where H is protium (H) and deuteroxyl (OD), where D is deuterium (H)) of less than about 20 ppm by weight in one embodiment, less than about 5 ppm by weight in another embodiment, and less than about 1 ppm by weight in a third embodiment.

US Patent:

20050063663, Mar 24, 2005

Filed:

Aug 27, 2004

Appl. No.:

10/929142

Inventors:

James Anderson - Dundee NY, US
Dana Bookbinder - Corning NY, US
Lisa Chacon - Corning NY, US
Calvin Coffey - Watkins Glen NY, US
Adam Ellison - Painted Post NY, US
Gregory Gausman - Wilmington NC, US
Rostislav Khrapko - Corning NY, US
Stephan Logunov - Corning NY, US
Michael Murtagh - Painted Post NY, US
Clinton Osterhout - Beaver Dams NY, US
Sabyasachi Sen - Painted Post NY, US
William Whedon - Wilmington NC, US

International Classification:

G02B006/00

US Classification:

385142000

Abstract:

Disclosed is an optical fiber having a core with an alkali metal oxide dopant in an peak amount greater than about 0.002 wt. % and less than about 0.1 wt. %. The alkali metal oxide concentration varies with a radius of the optical fiber. By appropriately selecting the concentration of alkali metal oxide dopant in the core and the cladding, a low loss optical fiber may be obtained. Also disclosed are several methods of making the optical fiber including the steps of forming an alkali metal oxide-doped rod, and adding additional glass to form a draw perform. Preferably, the draw preform has a final outer dimension (d2), wherein an outer dimension (d1) of the rod is less than or equal to 0.06 times the final outer dimension (d2). In a preferred embodiment, the alkali metal oxide-doped rod is inserted into the centerline hole of a preform to form an assembly.

US Patent:

20220306516, Sep 29, 2022

Filed:

May 24, 2022

Appl. No.:

17/752279

Inventors:

- Corning NY, US
Rostislav Radiyevich Khrapko - Corning NY, US

International Classification:

C03B 37/012

Abstract:

The vacuum-based methods of forming an optical fiber preform include applying a vacuum to a preform assembly. The preform assembly has at least one glass cladding section with one or more axial through holes, with one or more canes respectively residing in the one or more axial through holes. The opposite ends of the at least one glass cladding section are capped to define a substantially sealed internal chamber. A vacuum is applied to the substantially sealed internal chamber to define a vacuum-held preform assembly. The methods also include heating the vacuum-held preform assembly to just above the glass softening point to consolidate the vacuum-held preform to form the cane-based glass preform. An optical fiber is formed by drawing the cane-based glass preform. The same furnace used to consolidate the vacuum-held preform can be used to draw the optical fiber.