Patents by Inventor Todd H. Stievater

Todd H. Stievater 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).

  • Publication number: 20240036259
    Abstract: An apparatus includes a polarization rotator or a polarization splitter. The polarization rotator and the polarization splitter each includes a first optical waveguide. The polarization rotator further includes a movable symmetry-breaking micro-electro-mechanical systems (“MEMS”) dielectric perturber separated from the first optical waveguide by a gap. The first optical waveguide and the MEMS dielectric perturber define a gap therebetween. The polarization rotator also includes a MEMS actuator moving the MEMS dielectric perturber so as to control the gap, thereby controlling polarization rotation within the first optical waveguide. The polarization splitter includes a second optical waveguide separated from the first optical waveguide by a gap. The polarization splitter also includes a MEMS actuator moving the first optical waveguide and/or the second optical waveguide so as to control the gap, thereby controlling polarization splitting between the optical waveguides.
    Type: Application
    Filed: July 14, 2023
    Publication date: February 1, 2024
    Inventors: Marcel W. Pruessner, Todd H. Stievater, Nathan F. Tyndall
  • Publication number: 20230417988
    Abstract: Method and apparatuses for photonic filtering using n-stage nonuniform lattice filters are provided. The n-stage nonuniform lattice filters includes a plurality of directional coupler-differential delay devices connected in series and an end-stage directional coupler. Each of the directional coupler-differential delay devices includes a directional coupler section and a differential delay section. Each directional coupler section has a corresponding coupling constant. Each differential delay section has a corresponding differential delay. A first of the plurality of directional coupler-differential delay devices is constructed to receive a pump and a signal. The end-stage directional coupler is connected in series to a last of the plurality of directional coupler-differential delay devices and includes an input port, a through port, and a cross port.
    Type: Application
    Filed: June 22, 2023
    Publication date: December 28, 2023
    Inventors: Todd H. Stievater, Nathan Tyndall
  • Patent number: 11754785
    Abstract: Methods and apparatuses for mode conversion. An apparatus that includes a substrate, a first waveguide, a second waveguide, a micro-electro-mechanical systems (MEMS) perturber, and a controller is provided. The first waveguide is formed on the substrate includes: (i) an input section, (ii) a bend section, and (iii) an output section. The second waveguide is also formed on the substrate and is disposed adjacent to a portion of the input section of the first waveguide. A portion of the second waveguide is separated from the input section of the first waveguide by a coupling gap. The perturber is disposed above the first waveguide and configured to move between a first position that is distal from a surface of the input section of the first waveguide and a second position that is closer to the surface of the input section of the first waveguide than the second position. The controller is configured to control a movement of the perturber between the first position and the second position.
    Type: Grant
    Filed: August 20, 2021
    Date of Patent: September 12, 2023
    Assignee: The Government of the United States of America, as represented by the Secretary of the Navy
    Inventors: Marcel W. Pruessner, Dmitry A. Kozak, Todd H. Stievater, Brian J. Roxworthy
  • Patent number: 11692982
    Abstract: Presented herein is a new concept of uniformly spin coating a flat surface with a stationary phase and creating a gas chromatography column by pressing a grooved lid, with micro-stamped ridges, down onto the coated substrate. The lids are molded out of commercially available rigid materials including epoxies so that when pressed onto a flat surface it will create an air tight seal. The epoxy material is rendered inert by a thin layer of gold.
    Type: Grant
    Filed: May 8, 2020
    Date of Patent: July 4, 2023
    Assignee: The Government of the United States of America, as represented by the Secretary of the Navy
    Inventors: Robert Furstenberg, Christopher Breshike, Todd H. Stievater, Dmitry Kozak, R. Andrew McGill
  • Publication number: 20230184623
    Abstract: A method and system for obtaining photonic parameters. The system includes a computer, an optical source, a first and second optical fiber, a Mach-Zehnder Interferometer (MZI) structure, and a detector. The computer includes a processor and memory. The optical source is constructed to emit light of a first optical mode and a second optical mode in response to an instruction by the computer. The first optical fiber receives the first or second optical mode. The MZI structure includes first and second pluralities MZIs and receives the first or second optical mode from the optical fiber. The second optical fiber receives light from the MZI structure. The detector is configured to receive light that propagated through the second optical fiber, generate image data and provide the image data to the computer. The computer obtains a plurality of photonic parameters based on the image data and initial guesses for the plurality of photonic parameters.
    Type: Application
    Filed: December 14, 2022
    Publication date: June 15, 2023
    Inventors: Todd H. Stievater, Nathan Tyndall, Marcel W. Pruessner
  • Publication number: 20230055779
    Abstract: Methods and apparatuses for mode conversion. An apparatus that includes a substrate, a first waveguide, a second waveguide, a micro-electro-mechanical systems (MEMS) perturber, and a controller is provided. The first waveguide is formed on the substrate includes: (i) an input section, (ii) a bend section, and (iii) an output section. The second waveguide is also formed on the substrate and is disposed adjacent to a portion of the input section of the first waveguide. A portion of the second waveguide is separated from the input section of the first waveguide by a coupling gap. The perturber is disposed above the first waveguide and configured to move between a first position that is distal from a surface of the input section of the first waveguide and a second position that is closer to the surface of the input section of the first waveguide than the second position. The controller is configured to control a movement of the perturber between the first position and the second position.
    Type: Application
    Filed: August 20, 2021
    Publication date: February 23, 2023
    Inventors: Marcel W. Pruessner, Dmitry A. Kozak, Todd H. Stievater, Brian J. Roxworthy
  • Publication number: 20200355652
    Abstract: Presented herein is a new concept of uniformly spin coating a flat surface with a stationary phase and creating a gas chromatography column by pressing a grooved lid, with micro-stamped ridges, down onto the coated substrate. The lids are molded out of commercially available rigid materials including epoxies so that when pressed onto a flat surface it will create an air tight seal. The epoxy material is rendered inert by a thin layer of gold.
    Type: Application
    Filed: May 8, 2020
    Publication date: November 12, 2020
    Inventors: Robert Furstenberg, Christopher Breshike, Todd H. Stievater, Dmitry Kozak, R. Andrew McGill
  • Patent number: 10302601
    Abstract: A chemical detector for rapid, simultaneous detection of multiple chemicals including chemical warfare agents, toxic industrial chemicals, and explosives having one or more gas chromatography columns each with a chemosorbent or a chemo-reactive stationary phase and an infrared-transparent base, a bright infrared light source, a mechanism to direct the light source to any point along any of the columns, and an infrared sensor. Another disclosed detector has one or more gas chromatography columns each on the surface of a substrate having at least one infrared-transparent waveguide pattern, a bright infrared light source, and at least one ring resonator for each column, where each ring resonator is coated with a chemosorbent or a chemo-reactive stationary phase, and where each ring resonator spectroscopically probes the stationary phase. Also disclosed are the related methods for chemical detection.
    Type: Grant
    Filed: March 21, 2017
    Date of Patent: May 28, 2019
    Assignee: The United States of America, as represented by the Secretary of the Navy
    Inventors: R. Andrew McGill, Robert Furstenberg, Viet K. Nguyen, Chris Kendziora, Michael Papantonakis, Todd H. Stievater
  • Patent number: 10054546
    Abstract: A system and method for detecting an analyte includes a waveguide configured to receive a narrow-band laser signal; and a sorbent material covering an analyte detection region of the waveguide, wherein the sorbent material is configured to sorb the analyte and bring the analyte to an evanescent field of the waveguide, and wherein Raman scattering is produced by an interaction of the evanescent field and the analyte sorbed in the sorbent material along the analyte detection region of the waveguide, and the waveguide is further configured to collect the Raman scattering along the analyte detection region of the waveguide, wherein the collected Raman scattering indicates a type of the analyte.
    Type: Grant
    Filed: October 14, 2016
    Date of Patent: August 21, 2018
    Assignee: The United States of America, as represented by the Secretary of the Navy
    Inventors: Todd H. Stievater, Jacob B. Khurgin, Dmitry A. Kozak, Scott A. Holmstrom, R. Andrew McGill
  • Publication number: 20170284976
    Abstract: A chemical detector for rapid, simultaneous detection of multiple chemicals including chemical warfare agents, toxic industrial chemicals, and explosives having one or more gas chromatography columns each with a chemosorbent or a chemo-reactive stationary phase and an infrared-transparent base, a bright infrared light source, a mechanism to direct the light source to any point along any of the columns, and an infrared sensor. Another disclosed detector has one or more gas chromatography columns each on the surface of a substrate having at least one infrared-transparent waveguide pattern, a bright infrared light source, and at least one ring resonator for each column, where each ring resonator is coated with a chemosorbent or a chemo-reactive stationary phase, and where each ring resonator spectroscopically probes the stationary phase. Also disclosed are the related methods for chemical detection.
    Type: Application
    Filed: March 21, 2017
    Publication date: October 5, 2017
    Inventors: R. Andrew McGill, Robert Furstenberg, Viet K. Nguyen, Chris Kendziora, Michael Papantonakis, Todd H. Stievater
  • Patent number: 9759552
    Abstract: A method and system described for sensing a displacement by receiving and propagating a laser light signal with an etched waveguide that is configured to enable an evanescent optical field above the waveguide surface. A movable perturber can be positioned so the perturber interacts with the evanescent optical field above the waveguide surface. An optical phase shift can be induced in the waveguide when the movable perturber is displaced in the evanescent optical field, and the optical phase shift can be measured with an optical readout circuit.
    Type: Grant
    Filed: May 31, 2016
    Date of Patent: September 12, 2017
    Assignee: The United States of America, as represented by the Secretary of the Navy
    Inventors: Marcel W. Pruessner, Todd H. Stievater, William S. Rabinovich
  • Publication number: 20170108439
    Abstract: A system and method for detecting an analyte includes a waveguide configured to receive a narrow-band laser signal; and a sorbent material covering an analyte detection region of the waveguide, wherein the sorbent material is configured to sorb the analyte and bring the analyte to an evanescent field of the waveguide, and wherein Raman scattering is produced by an interaction of the evanescent field and the analyte sorbed in the sorbent material along the analyte detection region of the waveguide, and the waveguide is further configured to collect the Raman scattering along the analyte detection region of the waveguide, wherein the collected Raman scattering indicates a type of the analyte.
    Type: Application
    Filed: October 14, 2016
    Publication date: April 20, 2017
    Inventors: Todd H. Stievater, Jacob B. Khurgin, Dmitry A. Kozak, Scott A. Holmstrom, R. Andrew McGill
  • Patent number: 9599567
    Abstract: A chemical detector for rapid, simultaneous detection of multiple chemicals including chemical warfare agents, toxic industrial chemicals, and explosives having one or more gas chromatography columns each with a chemosorbent or a chemo-reactive stationary phase and an infrared-transparent base, a bright infrared light source, a mechanism to direct the light source to any point along any of the columns, and an infrared sensor. Another disclosed detector has one or more gas chromatography columns each on the surface of a substrate having at least one infrared-transparent waveguide pattern, a bright infrared light source, and at least one ring resonator for each column, where each ring resonator is coated with a chemosorbent or a chemo-reactive stationary phase, and where each ring resonator spectroscopically probes the stationary phase. Also disclosed are the related methods for chemical detection.
    Type: Grant
    Filed: March 13, 2014
    Date of Patent: March 21, 2017
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: R. Andrew McGill, Robert Furstenberg, Viet K. Nguyen, Chris Kendziora, Michael Papantonakis, Todd H. Stievater
  • Publication number: 20160273912
    Abstract: A method and system described for sensing a displacement by receiving and propagating a laser light signal with an etched waveguide that is configured to enable an evanescent optical field above the waveguide surface. A movable perturber can be positioned so the perturber interacts with the evanescent optical field above the waveguide surface. An optical phase shift can be induced in the waveguide when the movable perturber is displaced in the evanescent optical field, and the optical phase shift can be measured with an optical readout circuit.
    Type: Application
    Filed: May 31, 2016
    Publication date: September 22, 2016
    Inventors: Marcel W. Pruessner, Todd H. Stievater, William S. Rabinovich
  • Patent number: 9395177
    Abstract: A method and system described for sensing a displacement by receiving and propagating a laser light signal with an etched waveguide that is configured to enable an evanescent optical field above the waveguide surface. A movable perturber can be positioned so the perturber interacts with the evanescent optical field above the waveguide surface. An optical phase shift can be induced in the waveguide when the movable perturber is displaced in the evanescent optical field, and the optical phase shift can be measured with an optical readout circuit.
    Type: Grant
    Filed: November 12, 2014
    Date of Patent: July 19, 2016
    Assignee: The United States of America, as represented by the Secretary of the Navy
    Inventors: Marcel W. Pruessner, Todd H. Stievater, William S. Rabinovich
  • Patent number: 9335271
    Abstract: A mass sensor system including multiple Fabry-Perot microcavities connected in parallel by multiple waveguides. Each of the mass sensors includes a microbridge having a fundamental resonance frequency, and a movable reflective mirror etched into the microbridge; a fixed reflective mirror etched in a substrate, the fixed reflective mirror being fixed to the substrate in a region spaced apart from the movable reflective mirror; and an optical waveguide etched in the substrate that connects the movable mirror and the fixed mirror forming the Fabry-Perot microcavity interferometer. The system includes a tunable continuous-wave laser operative to optically interrogate the Fabry-Perot microcavity of each of the plurality of mass sensors, and a receiver operative to receive sensor signals from each of the plurality of mass sensors, the sensor signals comprising reflective signals and transmitted signals.
    Type: Grant
    Filed: August 22, 2014
    Date of Patent: May 10, 2016
    Assignee: The Government of the United States of America, as represented by the Secretary of the Navy
    Inventors: Marcel W. Pruessner, Todd H. Stievater, William S. Rabinovich
  • Publication number: 20150323466
    Abstract: A mass sensor system including multiple Fabry-Perot microcavities connected in parallel by multiple waveguides. Each of the mass sensors includes a microbridge having a fundamental resonance frequency, and a movable reflective mirror etched into the microbridge; a fixed reflective mirror etched in a substrate, the fixed reflective mirror being fixed to the substrate in a region spaced apart from the movable reflective mirror; and an optical waveguide etched in the substrate that connects the movable mirror and the fixed mirror forming the Fabry-Perot microcavity interferometer. The system includes a tunable continuous-wave laser operative to optically interrogate the Fabry-Perot microcavity of each of the plurality of mass sensors, and a receiver operative to receive sensor signals from each of the plurality of mass sensors, the sensor signals comprising reflective signals and transmitted signals.
    Type: Application
    Filed: August 22, 2014
    Publication date: November 12, 2015
    Applicant: The Government of the United States of America, as represented by the Secretary of the Navy
    Inventors: Marcel W. Pruessner, Todd H. Stievater, William S. Rabinovich
  • Patent number: 9057891
    Abstract: A waveguide device for frequency mixing or conversion through birefringent phase matching, having a horizontal waveguide suspended above a substrate. The waveguide is formed of a zinc blend type III-V semiconductor material with a high nonlinear susceptibility.
    Type: Grant
    Filed: April 22, 2013
    Date of Patent: June 16, 2015
    Assignee: The United States of America, as represented by the Secretary of the Navy
    Inventors: Todd H. Stievater, Jacob B. Khurgin, Doewon Park, Marcel W. Pruessner, William S. Rabinovich, Rita Mahon
  • Publication number: 20150131106
    Abstract: A method and system described for sensing a displacement by receiving and propagating a laser light signal with an etched waveguide that is configured to enable an evanescent optical field above the waveguide surface. A movable perturber can be positioned so the perturber interacts with the evanescent optical field above the waveguide surface. An optical phase shift can be induced in the waveguide when the movable perturber is displaced in the evanescent optical field, and the optical phase shift can be measured with an optical readout circuit.
    Type: Application
    Filed: November 12, 2014
    Publication date: May 14, 2015
    Applicant: The Government of the United States of America, as represented by the Secretary of the Navy
    Inventors: Marcel W. Pruessner, Todd H. Stievater, William S. Rabinovich
  • Patent number: 8848197
    Abstract: A mass sensor system including multiple Fabry-Perot microcavities connected in parallel by multiple waveguides. Each of the mass sensors includes a microbridge having a fundamental resonance frequency, and a movable reflective mirror etched into the microbridge; a fixed reflective mirror etched in a substrate, the fixed reflective mirror being fixed to the substrate in a region spaced apart from the movable reflective mirror; and an optical waveguide etched in the substrate that connects the movable mirror and the fixed mirror forming the Fabry-Perot microcavity interferometer. The system includes a tunable continuous-wave laser operative to optically interrogate the Fabry-Perot microcavity of each of the plurality of mass sensors, and a receiver operative to receive sensor signals from each of the plurality of mass sensors, the sensor signals comprising reflective signals and transmitted signals.
    Type: Grant
    Filed: July 18, 2013
    Date of Patent: September 30, 2014
    Assignee: The United States of America, as represented by the Secretary of the Navy
    Inventors: Marcel W. Pruessner, Todd H. Stievater, William S. Rabinovich