Thomas J Dougherty

US Patent:

7683854, Mar 23, 2010

Filed:

Feb 9, 2006

Appl. No.:

11/350429

Inventors:

Daniel F. Sievenpiper - Los Angeles CA, US
Thomas K. Dougherty - Playa Del Rey CA, US
John J. Drab - Santa Barbara CA, US
Solomon O. Robinson - Oxnard CA, US

Assignee:

Raytheon Company - Waltham MA

International Classification:

H01Q 15/02

US Classification:

343909, 343700 MS, 4551931

Abstract:

A tunable impedance surface includes a varactor. The varactor comprises a bottom electrode formed on a surface of a substrate. First and second ferroelectric elements are on top of the bottom electrode and electrically connected to one another through the bottom electrode. A first top electrode is on top of and electrically connected to the first ferroelectric element and a second top electrode is on top of and electrically connected to the second ferroelectric element.

US Patent:

48661562, Sep 12, 1989

Filed:

Jul 29, 1987

Appl. No.:

7/079189

Inventors:

Thomas K. Dougherty - Irvine CA

Assignee:

Hughes Aircraft Copmany - Los Angeles CA

International Classification:

C08G 6538
C08G 7504

US Classification:

528219

Abstract:

Novel processes are provided for synthesizing 2,2-bis(4-fluorophenyl)hexafluoropropane and the use of this synthesized monomer in polymerization reactions to form poly(arylethers) or poly(arylthioethers). Synthesis of 2,2-bis(4-fluorophenyl)hexafluoropropane involves converting the commonly available compound Bisphenol AF to an amino-substituted form, followed by treatment with borofluoric acid and a nitrite, and then an aromatic solvent to obtain the monomer. The monomer can be mixed with either a dihydroxy diphenyl hexafluoropropane or a dimercapto diphenyl hexafluorpropane to cause a nucleophilic substitution reaction, thereby yielding the desired poly(arylether) or poly(arylthioether).

US Patent:

48270547, May 2, 1989

Filed:

Jul 18, 1988

Appl. No.:

7/221003

Inventors:

Thomas K. Dougherty - Irvine CA

Assignee:

Hughes Aircraft Company - Los Angeles CA

International Classification:

C07C 1722
C07C 2118

US Classification:

570141

Abstract:

Novel processes are provided for synthesizing 2,2-bis(4-fluorophenyl)hexafluoropropane and the use of this synthesized monomer in polymerization reactions to form poly(arylethers) and poly(arylthioethers). Synthesis of 2,2-bis(4-fluorophenyl)hexafluoropropane involves converting the commonly available compound Bisphenol AF to an amino-substituted form, followed by treatment with borofluoric acid and a nitrite, and then an aromatic solvent to obtain the monomer. The monomer can be mixed with either a dihydroxy diphenyl hexafluoropropane or a dimercapto diphenyl hexafluorpropane to cause a nucleophilic substitution reaction, thereby yielding the desired poly(arylether) or poly(arylthioether).

US Patent:

57715670, Jun 30, 1998

Filed:

Aug 29, 1996

Appl. No.:

8/705508

Inventors:

Brian M. Pierce - Moreno Valley CA
Norman H. Harris - Newhall CA
Thomas Kirk Dougherty - Playa del Rey CA
William W. Chen - Westchester CA
Florentino V. Lee - Culver City CA

Assignee:

Raytheon Company - Lexington MA

International Classification:

H01P 1100

US Classification:

29600

Abstract:

Methods of fabricating a porous ceramic composite having voltage-variable dielectric properties. The composite is made as follows. A polycrystalline ferroelectric powder, which is a ferroelectric perovskite such as barium strontium titanate, for example, is provided. The powder, a binder and a filler are then mixed in water to form a slurry. The powder-binder-filler slurry is then dried. The dried powder-binder-filler slurry is granulated. The granulated powder-binder-filler is pressed into a die. The binder and filler are then burned out to form a fragile porous ash-like structure. The porous structure is then sintered to form porous ceramic parts. The porous ceramic parts are then machined tiles. The machined porous tiles may then be tested for microwave properties. Fabrication methods for producing porous ferroelectric ceramic-polymer composite tiles or subaperture blanks and continuous transverse stub electronically scanned antenna plates or subapertures are also disclosed.