Patents by Inventor Frederick G Johnson

Frederick G Johnson has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7973265
    Abstract: An integrated optical device is disclosed comprising a substrate, optical waveguide, and compound optical resonator having a temperature sensor, at least two coupled optical resonators, and a heater localized to each optical resonator. An optical input signal is coupled to one of the resonators making up the compound resonator to form an optical output signal. The center wavelength and shape of the output signal is optimized with a feedback loop using the temperature sensor to control the power dissipated in at least one of the localized heaters. The power dissipated in the remaining resonator heaters is set according to a predetermined function having as an input variable the power dissipated in the resonant heater under control of the said feedback loop.
    Type: Grant
    Filed: August 31, 2009
    Date of Patent: July 5, 2011
    Assignee: Infinera Corporation
    Inventors: Sai Chu, Frederick G. Johnson, Oliver King, Marcus Schuetz, Brent Little
  • Patent number: 7903910
    Abstract: An integrated optical device is disclosed comprising a substrate, optical waveguide, and compound optical resonator having a temperature sensor, at least two coupled optical resonators, and a heater localized to each optical resonator. An optical input signal is coupled to one of the resonators making up the compound resonator to form an optical output signal. The center wavelength and shape of the output signal is optimized with a feedback loop using the temperature sensor to control the power dissipated in at least one of the localized heaters. The power dissipated in the remaining resonator heaters is set according to a predetermined function having as an input variable the power dissipated in the resonant heater under control of the said feedback loop.
    Type: Grant
    Filed: March 28, 2008
    Date of Patent: March 8, 2011
    Assignee: Infinera Corporation
    Inventors: Sai Chu, Frederick G. Johnson, Oliver King, Marcus Schuetz, Brent Little
  • Publication number: 20090314763
    Abstract: An integrated optical device is disclosed comprising a substrate, optical waveguide, and compound optical resonator having a temperature sensor, at least two coupled optical resonators, and a heater localized to each optical resonator. An optical input signal is coupled to one of the resonators making up the compound resonator to form an optical output signal. The center wavelength and shape of the output signal is optimized with a feedback loop using the temperature sensor to control the power dissipated in at least one of the localized heaters. The power dissipated in the remaining resonator heaters is set according to a predetermined function having as an input variable the power dissipated in the resonant heater under control of the said feedback loop.
    Type: Application
    Filed: August 31, 2009
    Publication date: December 24, 2009
    Inventors: Sai Chu, Frederick G. Johnson, Oliver King, Marcus Schuetz, Brent Little
  • Patent number: 7583879
    Abstract: An integrated optical device is disclosed comprising a substrate, optical waveguide, and compound optical resonator having a temperature sensor, at least two coupled optical resonators, and a heater localized to each optical resonator. An optical input signal is coupled to one of the resonators making up the compound resonator to form an optical output signal. The center wavelength and shape of the output signal is optimized with a feedback loop using the temperature sensor to control the power dissipated in at least one of the localized heaters. The power dissipated in the remaining resonator heaters is set according to a predetermined function having as an input variable the power dissipated in the resonant heater under control of the said feedback loop.
    Type: Grant
    Filed: May 7, 2007
    Date of Patent: September 1, 2009
    Assignee: Infinera Corporation
    Inventors: Sai Chu, Frederick G. Johnson, Oliver King, Marcus Schuetz, Brent Little
  • Patent number: 7435944
    Abstract: An optically-powered integrated microstructure pressure sensing system for sensing pressure within a cavity. The pressure sensing system comprises a pressure sensor having an optical resonant structure subject to the pressure within the cavity and having physical properties changing due to changing pressures within the cavity. A substrate supports the optical resonant structure. An input optical pathway evanescently couples light into the optical resonant structure. An output optical pathway collects light from the optical resonance structure. A light source delivers a known light input into the input optical pathway whereby the known light input is evanescently coupled into the optical resonant structure by the input optical pathway and a portion of such light is collected from the optical resonant structure by the output optical pathway.
    Type: Grant
    Filed: March 5, 2007
    Date of Patent: October 14, 2008
    Assignee: Nomadics, Inc.
    Inventors: Shiou-jyh Ja, Lloyd Salsman, Brian Strecker, Robert Shelton, Frederick G. Johnson
  • Publication number: 20080175538
    Abstract: An integrated optical device is disclosed comprising a substrate, optical waveguide, and compound optical resonator having a temperature sensor, at least two coupled optical resonators, and a heater localized to each optical resonator. An optical input signal is coupled to one of the resonators making up the compound resonator to form an optical output signal. The center wavelength and shape of the output signal is optimized with a feedback loop using the temperature sensor to control the power dissipated in at least one of the localized heaters.
    Type: Application
    Filed: March 28, 2008
    Publication date: July 24, 2008
    Inventors: Sai Chu, Frederick G. Johnson, Oliver King, Marcus Schuetz, Brent Little
  • Patent number: 7356221
    Abstract: An integrated optical device is disclosed comprising a substrate, optical waveguide, and compound optical resonator having a temperature sensor, at least two coupled optical resonators, and a heater localized to each optical resonator. An optical input signal is coupled to one of the resonators making up the compound resonator to form an optical output signal. The center wavelength and shape of the output signal is optimized with a feedback loop using the temperature sensor to control the power dissipated in at least one of the localized heaters. The power dissipated in the remaining resonator heaters is set according to a predetermined function having as an input variable the power dissipated in the resonant heater under control of the said feedback loop.
    Type: Grant
    Filed: May 7, 2007
    Date of Patent: April 8, 2008
    Assignee: Infinera Corporation
    Inventors: Sai Chu, Frederick G. Johnson, Oliver King, Marcus Schuetz, Brent Little
  • Patent number: 7244926
    Abstract: An optically-powered integrated microstructure pressure sensing system for sensing pressure within a cavity. the pressure sensing system comprises a pressure sensor having an optical resonant structure subject to the pressure within the cavity and having physical properties changing due to changing pressures within the cavity. A substrate supports the optical resonant structure. An input optical pathway evanescently couples light into the optical resonant structure. An output optical pathway collects light from the optical resonance structure. A light source delivers a known light input into the input optical pathway whereby the known light input is evanescently coupled into the optical resonant structure by the input optical pathway and a portion of such light is collected from the optical resonant structure by the output optical pathway.
    Type: Grant
    Filed: February 28, 2005
    Date of Patent: July 17, 2007
    Assignee: Nomadics, Inc.
    Inventors: Shiou-jyh Ja, Lloyd Salsman, Brian Strecker, Robert Shelton, Frederick G. Johnson
  • Patent number: 7231113
    Abstract: An integrated optical device is disclosed comprising a substrate, optical waveguide, and compound optical resonator having a temperature sensor, at least two coupled optical resonators, and a heater localized to each optical resonator. An optical input signal is coupled to one of the resonators making up the compound resonator to form an optical output signal. The center wavelength and shape of the output signal is optimized with a feedback loop using the temperature sensor to control the power dissipated in at least one of the localized heaters. The power dissipated in the remaining resonator heaters is set according to a predetermined function having as an input variable the power dissipated in the resonant heater under control of the said feedback loop.
    Type: Grant
    Filed: August 19, 2005
    Date of Patent: June 12, 2007
    Assignee: Infinera Corporation
    Inventors: Sai Chu, Frederick G. Johnson, Oliver King, Marcus Schuetz, Brent Little
  • Patent number: 7043133
    Abstract: Silicon-oxycarbide optical waveguides and thermooptic devices include a substrate and a first cladding layer having a first refractive index positioned over a substrate. A first core layer comprising silicon, oxygen, and carbon and having a core refractive index is formed on the first cladding layer by chemical vapor deposition using at least two precursors: one inorganic silicon precursor gas and at least one second precursor gas comprising carbon and oxygen. Alternatively, at least three precursors can be used: one inorganic silicon precursor gas, a second precursor comprising carbon, and a third precursor comprising oxygen. The core layer is lithographically patterned to define waveguide elements. A second cladding layer having a second cladding refractive index is formed to surround the optical core waveguiding element of the first core layer.
    Type: Grant
    Filed: June 10, 2004
    Date of Patent: May 9, 2006
    Assignee: Little Optics, Inc.
    Inventors: Frederick G. Johnson, Oliver S. King, David M. Gill, Timothy J. Davidson, Warren P. Berk
  • Patent number: 6949392
    Abstract: The integrated optical circuit of the present invention includes a substrate with a first cladding layer. A first core layer having one or more waveguiding elements is formed on the first cladding layer. A second cladding layer surrounds the waveguiding elements of the first core layer; the refractive index of the first and second cladding layers are selected to be less than the refractive index of the waveguiding element(s). Through simultaneous cladding material deposition and cladding material removal, the second cladding layer as deposited is substantially self-planarized, enabling further layers to be positioned on the second cladding layer without necessitating intermediate planarization. Further, the present invention permits planar waveguide cores having submicron core spacings to be covered by a subsequently-deposited cladding layer without cladding gaps, seams or other deleterious cladding defects.
    Type: Grant
    Filed: May 4, 2004
    Date of Patent: September 27, 2005
    Assignee: Little Optics, Inc.
    Inventors: David M. Gill, Frederick G Johnson, Oliver S. King
  • Publication number: 20040240820
    Abstract: Silicon-oxycarbide optical waveguides and thermooptic devices include a substrate and a first cladding layer having a first refractive index positioned over a substrate. A first core layer comprising silicon, oxygen, and carbon and having a core refractive index is formed on the first cladding layer by chemical vapor deposition using at least two precursors: one inorganic silicon precursor gas and at least one second precursor gas comprising carbon and oxygen. Alternatively, at least three precursors can be used: one inorganic silicon precursor gas, a second precursor comprising carbon, and a third precursor comprising oxygen. The core layer is lithographically patterned to define waveguide elements. A second cladding layer having a second cladding refractive index is formed to surround the optical core waveguiding element of the first core layer.
    Type: Application
    Filed: June 10, 2004
    Publication date: December 2, 2004
    Inventors: Frederick G. Johnson, Oliver S. King, David M. Gill, Timothy J. Davidson, Warren P. Berk
  • Publication number: 20040201026
    Abstract: The integrated optical circuit of the present invention includes a substrate with a first cladding layer. A first core layer having one or more waveguiding elements is formed on the first cladding layer. A second cladding layer surrounds the waveguiding elements of the first core layer; the refractive index of the first and second cladding layers are selected to be less than the refractive index of the waveguiding element(s). Through simultaneous cladding material deposition and cladding material removal, the second cladding layer as deposited is substantially self-planarized, enabling further layers to be positioned on the second cladding layer without necessitating intermediate planarization Further, the present invention permits planar waveguide cores having submicron core spacings to be covered by a subsequently-deposited cladding layer without cladding gaps, seams or other deleterious cladding defects.
    Type: Application
    Filed: May 4, 2004
    Publication date: October 14, 2004
    Inventors: David M. Gill, Frederick G. Johnson, Oliver S. King
  • Patent number: 6771868
    Abstract: Devices and methods for the vapor deposition of amorphous, silicon-containing thin films using vapors comprised of deuterated species. Thin films grown on a substrate wafer by this method contain deuterium but little to no hydrogen. Optical devices comprised of optical waveguides formed using this method have significantly reduced optical absorption or loss in the near-infrared optical spectrum commonly used for optical communications, compared to the loss in waveguides formed in thin films grown using conventional vapor deposition techniques with hydrogen containing precursors. In one variation, the optical devices are formed on a silicon-oxide layer that is formed on a substrate, such as a silicon substrate. The optical devices of some variations are of the chemical species SiOxNy:D. Since the method of formation requires no annealing, the thin films can be grown on electronic and optical devices or portions thereof without damaging those devices.
    Type: Grant
    Filed: June 20, 2003
    Date of Patent: August 3, 2004
    Assignee: Little Optics, Inc.
    Inventors: Frederick G. Johnson, Oliver S. King, John V. Hryniewicz, Lance G. Joneckis, Sai T. Chu, David M. Gill
  • Patent number: 6768828
    Abstract: The integrated optical circuit of the present invention includes a substrate with a first cladding layer. A first core layer having one or more waveguiding elements is formed on the first cladding layer. A second cladding layer surrounds the waveguiding elements of the first core layer; the refractive index of the first and second cladding layers are selected to be less than the refractive index of the waveguiding element(s). Through simultaneous cladding material deposition and cladding material removal, the second cladding layer as deposited is substantially self-planarized, enabling further layers to be positioned on the second cladding layer without necessitating intermediate planarization. Further, the present invention permits planar waveguide cores having submicron core spacings to be covered by a subsequently-deposited cladding layer without cladding gaps, seams or other deleterious cladding defects.
    Type: Grant
    Filed: May 20, 2003
    Date of Patent: July 27, 2004
    Assignee: Little Optics Inc.
    Inventors: David M. Gill, Oliver S. King, Frederick G. Johnson
  • Publication number: 20040087049
    Abstract: The integrated optical circuit of the present invention includes a substrate with a first cladding layer. A first core layer having one or more waveguiding elements is formed on the first cladding layer. A second cladding layer surrounds the waveguiding elements of the first core layer; the refractive index of the first and second cladding layers are selected to be less than the refractive index of the waveguiding element(s). Through simultaneous cladding material deposition and cladding material removal, the second cladding layer as deposited is substantially self-planarized, enabling further layers to be positioned on the second cladding layer without necessitating intermediate planarization. Further, the present invention permits planar waveguide cores having submicron core spacings to be covered by a subsequently-deposited cladding layer without cladding gaps, seams or other deleterious cladding defects.
    Type: Application
    Filed: May 20, 2003
    Publication date: May 6, 2004
    Inventors: David M. Gill, Oliver S. King, Frederick G. Johnson
  • Publication number: 20030210880
    Abstract: Devices and methods for the vapor deposition of amorphous, silicon-containing thin films using vapors comprised of deuterated species. Thin films grown on a substrate wafer by this method contain deuterium but little to no hydrogen. Optical devices comprised of optical waveguides formed using this method have significantly reduced optical absorption or loss in the near-infrared optical spectrum commonly used for optical communications, compared to the loss in waveguides formed in thin films grown using conventional vapor deposition techniques with hydrogen containing precursors. In one variation, the optical devices are formed on a silicon-oxide layer that is formed on a substrate, such as a silicon substrate. The optical devices of some variations are of the chemical species SiOxNy:D. Since the method of formation requires no annealing, the thin films can be grown on electronic and optical devices or portions thereof without damaging those devices.
    Type: Application
    Filed: June 20, 2003
    Publication date: November 13, 2003
    Inventors: Frederick G. Johnson, Oliver S. King, John V. Hryniewicz, Lance G. Joneckis, Sai T. Chu, David M. Gill
  • Patent number: 6614977
    Abstract: Devices and methods for the vapor deposition of amorphous, silicon-containing thin films using vapors comprised of deuterated species. Thin films grown on a substrate wafer by this method contain deuterium but little to no hydrogen. Optical devices comprised of optical waveguides formed using this method have significantly reduced optical absorption or loss in the near-infrared optical spectrum commonly used for optical communications, compared to the loss in waveguides formed in thin films grown using conventional vapor deposition techniques with hydrogen containing precursors. In one variation, the optical devices are formed on a silicon-oxide layer that is formed on a substrate, such as a silicon substrate. The optical devices of some variations are of the chemical species SiOxNy:D. Since the method of formation requires no annealing, the thin films can be grown on electronic and optical devices or portions thereof without damaging those devices.
    Type: Grant
    Filed: September 4, 2001
    Date of Patent: September 2, 2003
    Assignee: Little Optics, Inc.
    Inventors: Frederick G. Johnson, Oliver S. King, John V. Hryniewicz, Lance G. Joneckis, Sai T. Chu, David M. Gill
  • Patent number: 6610612
    Abstract: A method of selectively oxidizing III-V semiconductor material is provided. There is provided a III-V semiconductor system comprising a short-period super lattice (SSL) of N periods of alternating layers of an aluminum-bearing III-V compound semiconductor material and a second III-V semiconductor material where N≧2, at least one phosphorous-rich III-V semiconductor layer, and at least one substantially phosphorous-free III-V semiconductor layer between each of the at least one phosphorous-rich layers and the SSL. The III-V semiconductor system is exposed to oxidizing atmosphere to selectively oxidize at least a portion of the SSL.
    Type: Grant
    Filed: December 12, 2001
    Date of Patent: August 26, 2003
    Assignees: The University of Maryland, The United States of America as represented by the National Security Agency
    Inventors: Mario Dagenais, Bikash Koley, Frederick G. Johnson
  • Patent number: 6531414
    Abstract: A method of forming a native oxide from at least one strain-compensated superlattice of Group III-V semiconductor material, where each at least one superlattice includes two monolayers of a Group III-V semiconductor material and at least two monolayers of an aluminum-bearing Group III-V semiconductor material. The method entails exposing each at least one superlattice to a water-containing environment and a temperature of at least about 425 degrees Celsius to convert at least a portion of said superlattice to a native oxide. The native oxide thus formed is useful in electrical and optoelectrical devices, such as lasers.
    Type: Grant
    Filed: May 2, 2000
    Date of Patent: March 11, 2003
    Assignee: The United States of America as represented by The National Security Agency
    Inventors: Frederick G. Johnson, Bikash Koley, Linda M. Wasiczko