Vinh P Nguyen

US Patent:

7418835, Sep 2, 2008

Filed:

Apr 15, 2004

Appl. No.:

10/824836

Inventors:

Vinh Q. Nguyen - Fairfax VA, US
Jasbinder S. Sanghera - Ashburn VA, US
Ishwar D. Aggarwal - Fairfax Station VA, US

Assignee:

The United States of America as represented by the Secretary of the Navy - Washington DC

International Classification:

C03B 32/02
C01B 17/02
C03C 3/32
C01G 28/00

US Classification:

65389, 65 331, 65DIG 15, 423 88, 423565, 117 73, 117 77, 501 40

Abstract:

This invention pertains to a chalcogenide glass of low optical loss that can be on the order of 30 dB/km or lower, and to a process for preparing the chalcogenide glass. The process includes the steps of optionally preparing arsenic monochalcogenide precursor or the precursor can be provided beforehand; dynamically distilling the precursor in an open system under vacuum from a hot section to a cold section to purify same; homogenizing the precursor in a closed system so that it is of a uniform color; disposing the distilled or purified precursor and at least one chalcogenide element at a hot section of an open distillation system; dynamically distilling under vacuum in an open system so that the precursor and the at least one chalcogenide element are deposited at a cold section of the open system in a more purified state; homogenizing the precursor and the at least chalcogenide element in a closed system while converting the precursor and the at least one chalcogenide element from crystalline phase to glassy phase.

US Patent:

7693388, Apr 6, 2010

Filed:

Sep 15, 2008

Appl. No.:

12/210467

Inventors:

Vinh Q Nguyen - Fairfax VA, US
Jasbinder S Sanghera - Ashburn VA, US
Ishwar D Aggarwal - Fairfax Station VA, US

Assignee:

The United States of America as represented by the Secretary of the Navy - Washington DC

International Classification:

G02B 6/00
G02B 6/02

US Classification:

385142, 385123, 385141, 385144

Abstract:

A thermally stable chalcogenide glass, a process for making the same, and an optical fiber drawn therefrom are provided. A chalcogenide glass having the composition GeAsSeTe(0≦y≦1 and 0≦x≦2) is substantially free from crystallization when it is heated past the glass transition temperature Tor drawn into optical fibers. A process for making the thermally stable chalcogenide glass includes purifying the components to remove oxides and scattering centers, batching the components in a preprocessed distillation ampoule, gettering oxygen impurities from the mixture, and heating the components to form a glass melt. An optical fiber formed from the chalcogenide glass is substantially free from crystallization and exhibits low signal loss in the near-infrared region, particularly at wavelengths of about 1. 55 μm.

US Patent:

7807595, Oct 5, 2010

Filed:

Jul 31, 2008

Appl. No.:

12/183095

Inventors:

Vinh Q Nguyen - Fairfax VA, US
Jasbinder S Sanghera - Ashburn VA, US
Ishwar D Aggarwal - Fairfax Station VA, US

Assignee:

The United States of America as represented by the Secretary of the Navy - Washington DC

International Classification:

C03C 3/32
C03C 13/04

US Classification:

501 37, 501 40

Abstract:

This invention pertains to a chalcogenide glass of low optical loss that can be on the order of 30 dB/km or lower, and to a process for preparing the chalcogenide glass. The process includes the steps of optionally preparing arsenic monochalcogenide precursor or the precursor can be provided beforehand; dynamically distilling the precursor in an open system under vacuum from a hot section to a cold section to purify same; homogenizing the precursor in a closed system so that it is of a uniform color; disposing the distilled or purified precursor and at least one chalcogenide element at a hot section of an open distillation system; dynamically distilling under vacuum in an open system so that the precursor and the at least one chalcogenide element are deposited at a cold section of the open system in a more purified state; homogenizing the precursor and the at least chalcogenide element in a closed system while converting the precursor and the at least one chalcogenide element from crystalline phase to glassy phase.

US Patent:

7844162, Nov 30, 2010

Filed:

Jun 25, 2009

Appl. No.:

12/491264

Inventors:

Vinh Q Nguyen - Fairfax VA, US
Jasbinder S. Sanghera - Ashburn VA, US
Ishwar D. Aggarwal - Fairfax Station VA, US

Assignee:

The United States of America as represented by the Secretary of the Navy - Washington DC

International Classification:

G02B 6/00
G02B 6/02
C03B 37/023

US Classification:

385142, 385123, 385141, 385144, 65385

Abstract:

A thermally stable chalcogenide glass, a process for making the same, and an optical fiber drawn therefrom are provided. A chalcogenide glass having the composition GeAsSeTe(0≦y≦1 and 0≦x≦2) is substantially free from crystallization when it is heated past the glass transition temperature Tor drawn into optical fibers. A process for making the thermally stable chalcogenide glass includes purifying the components to remove oxides and scattering centers, batching the components in a preprocessed distillation ampoule, gettering oxygen impurities from the mixture, and heating the components to form a glass melt. An optical fiber formed from the chalcogenide glass is substantially free from crystallization and exhibits low signal loss in the near-infrared region, particularly at wavelengths of about 1. 55 μm.

US Patent:

7891215, Feb 22, 2011

Filed:

Jun 18, 2010

Appl. No.:

12/818185

Inventors:

Vinh Q Nguyen - Fairfax VA, US
Jasbinder S. Sanghera - Ashburn VA, US
Ishwar D. Aggarwal - Fairfax Station VA, US

Assignee:

The United States of America as represented by the Secretary of the Navy - Washington DC

International Classification:

C03C 3/32
C03C 13/00

US Classification:

65389, 501 40

Abstract:

A thermally stable chalcogenide glass, a process for making the same, and an optical fiber drawn therefrom are provided. A chalcogenide glass having the composition GeAsSeTe(0≦y≦1 and 0≦x≦2) is substantially free from crystallization when it is heated past the glass transition temperature Tor drawn into optical fibers. A process for making the thermally stable chalcogenide glass includes purifying the components to remove oxides and scattering centers, batching the components in a preprocessed distillation ampoule, gettering oxygen impurities from the mixture, and heating the components to form a glass melt. An optical fiber formed from the chalcogenide glass is substantially free from crystallization and exhibits low signal loss in the near-infrared region, particularly at wavelengths of about 1. 55 μm.

US Patent:

8158096, Apr 17, 2012

Filed:

Oct 14, 2008

Appl. No.:

12/250808

Inventors:

Jesse A. Frantz - Landover MD, US
Jasbinder S Sanghera - Ashburn VA, US
Vinh Q Nguyen - Fairfax VA, US
Woohong Kim - Lorton VA, US
Ishwar D Aggarwal - Fairfax Station VA, US

Assignee:

The United States of America, as represented by the Secretary of the Navy - Washington DC

International Classification:

C01B 9/00

US Classification:

423464

Abstract:

The present invention is generally directed to a bulk barium copper sulfur fluoride (BCSF) material made by combining CuS, BaS and BaF, heating the ampoule between 400 and 550 C. for at least two hours, and then heating the ampoule at a temperature between 550 and 950 C. for at least two hours. The BCSF material may be doped with potassium, rubidium, or sodium. The present invention also provides for a BCSF transparent conductive thin film made by forming a sputter target by either hot pressing bulk BCSF or hot pressing CuS, BaS and BaFpowders and sputtering a BCSF thin film from the target onto a substrate. The present invention is further directed to a p-type transparent conductive material comprising a thin film of BCSF on a substrate where the film has a conductivity of at least 1 S/cm. The substrate may be a plastic substrate, such as a polyethersulfone, polyethylene terephthalate, polyimide, or some other suitable plastic or polymeric substrate.

US Patent:

20050043982, Feb 24, 2005

Filed:

Jul 29, 2004

Appl. No.:

10/901159

Inventors:

Vinh Nguyen - Burke VA, US

International Classification:

G06F017/60

US Classification:

705008000

Abstract:

A workflow modeling technique is proposed wherein a workflow is modeled as a modified finite-state machine executing strictly in the context of a data environment. The data environment isolates the state machine such that the only way to effect a change in the running status of the state machine is through modifications to the data environment. Each state in the state machine has a well-defined lifecycle. The progression of each state through its lifecycle and the transitions to other states are governed by user-defined business rules which operate on data drawn from the data environment. Business rules can also be defined to determine the executability of a particular task. Injection of data into the data environment can be accomplished either by programmatically setting values for user-defined variables or by users filling out forms interactively. User access to forms and individual data fields on a form is determined dynamically from the user's role and the current workflow status. Form layouts are handled automatically to accommodate for the visibility of individual data fields at any particular time. The task list for each user is extracted dynamically from the form access information and the current workflow data contents.

US Patent:

20100022378, Jan 28, 2010

Filed:

Jul 25, 2008

Appl. No.:

12/179797

Inventors:

Vinh Q. Nguyen - Fairfax VA, US
Jasbinder S. Sanghera - Ashburn VA, US
Shyam S. Bayya - Ashburn VA, US
Geoff Chin - Arlington VA, US
Ishwar D. Aggarwal - Fairfax Station VA, US

International Classification:

C03C 3/32
C03B 37/075

US Classification:

501 40, 65389, 203 29

Abstract:

The present invention is generally directed to a method of making chalcogenide glasses including holding the melt in a vertical furnace to promote homogenization and mixing; slow cooling the melt at less than 10 C. per minute; and sequentially quenching the melt from the top down in a controlled manner. Additionally, the present invention provides for the materials produced by such method. The present invention is also directed to a process for removing oxygen and hydrogen impurities from chalcogenide glass components using dynamic distillation.