Patents by Inventor Christopher I. Walker

Christopher I. Walker 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: 11536756
    Abstract: A method of setting phases of a multitude of transmit elements of a phased array includes, in part, setting a phase of a first transmit element to N different values during each of N different time intervals, transmitting an electromagnetic signal from the first transmit element at each of the N time intervals, measuring a power of the electromagnetic signal at a receiving unit during each of the N time intervals, and selecting coefficients of a basis function such that a difference between a power value computed by the basis function and the measured power value associated with each of the N phases is smaller than a threshold value. The threshold value is optionally defined by a minimum of the sum of squares of the difference between a power value computed by the basis function and the power value for each of the N phases.
    Type: Grant
    Filed: July 23, 2018
    Date of Patent: December 27, 2022
    Assignee: California Institute of Technology
    Inventors: Christopher I. Walker, Seyed Ali Hajimiri
  • Patent number: 10376892
    Abstract: PC board fluidic devices for performing a Polymerase Chain Reaction (PCR) are disclosed. The devices comprise a printed circuit board and a PCR chamber. The PCR chamber is a fluidic chamber and is located in, or is part of, the PC board. The PC board can include a coil trace heating element with a temperature sensor and controller.
    Type: Grant
    Filed: November 23, 2016
    Date of Patent: August 13, 2019
    Assignee: CALIFORNIA INSTITUTE OF TECHNOLOGY
    Inventors: Aditya Rajagopal, Samson Chen, Axel Scherer, Christopher I. Walker
  • Publication number: 20190219619
    Abstract: A method of setting phases of a multitude of transmit elements of a phased array includes, in part, setting a phase of a first transmit element to N different values during each of N different time intervals, transmitting an electromagnetic signal from the first transmit element at each of the N time intervals, measuring a power of the electromagnetic signal at a receiving unit during each of the N time intervals, and selecting coefficients of a basis function such that a difference between a power value computed by the basis function and the measured power value associated with each of the N phases is smaller than a threshold value. The threshold value is optionally defined by a minimum of the sum of squares of the difference between a power value computed by the basis function and the power value for each of the N phases.
    Type: Application
    Filed: July 23, 2018
    Publication date: July 18, 2019
    Inventors: Christopher I. Walker, Seyed Ali Hajimiri
  • Publication number: 20170072399
    Abstract: PC board fluidic devices for performing a Polymerase Chain Reaction (PCR) are disclosed. The devices comprise a printed circuit board and a PCR chamber. The PCR chamber is a fluidic chamber and is located in, or is part of, the PC board. The PC board can include a coil trace heating element with a temperature sensor and controller.
    Type: Application
    Filed: November 23, 2016
    Publication date: March 16, 2017
    Inventors: Aditya RAJAGOPAL, Samson CHEN, Axel SCHERER, Christopher I. WALKER
  • Patent number: 9533308
    Abstract: An apparatus for performing a Polymerase Chain Reaction (PCR) is disclosed. The apparatus comprises a PCR chamber for performing a Polymerase Chain Reaction and a printed circuit board (PCB) fluidic device. The PCR chamber is a fluidic chamber and is located in, or is part of, the printed circuit board (PCB) fluidic device. A method for manufacturing an apparatus for performing the Polymerase Chain Reaction and a method for performing the Polymerase Chain Reaction are further disclosed.
    Type: Grant
    Filed: February 8, 2013
    Date of Patent: January 3, 2017
    Assignee: CALIFORNIA INSTITUTE OF TECHNOLOGY
    Inventors: Aditya Rajagopal, Samson Chen, Axel Scherer, Christopher I. Walker
  • Patent number: 9316586
    Abstract: This invention provides a system for performing PCR, and real time PCR in particular, with great speed and specificity. The system employs a heat block containing a liquid composition to rapidly transfer heat to and from reaction vessels. The system makes use of the reflective properties of the liquid metal to reflect signal from the PCR into the vessel and out the top. In this way, the signal can be measured by an optical assembly in real time without removing the vessels from the heat block.
    Type: Grant
    Filed: March 9, 2012
    Date of Patent: April 19, 2016
    Assignee: California Institute of Technology
    Inventors: George Maltezos, Matthew Johnston, David Goodwin, Axel Scherer, Christopher I. Walker
  • Patent number: 8414785
    Abstract: Methods for fabrication of microfluidic systems on printed circuit boards (PCB) are described. The PCB contains layers of insulating material and a layer or layers of metal buried within layers of insulating material. The metal layers are etched away, leaving fully enclosed microfluidic channels buried within the layers of insulating material.
    Type: Grant
    Filed: October 1, 2009
    Date of Patent: April 9, 2013
    Assignee: California Institute of Technology
    Inventors: Christopher I. Walker, Aditya Rajagopal, Axel Scherer
  • Patent number: 8378689
    Abstract: An electrostatic sensor device including a first sensor element and a second sensor element; a dielectric substrate material formed in two layers, and a sensing hole which penetrates the dielectric substrate material from its upper surface to its lower surface. The first sensor element is receivable in the sensing hole; and second sensor element includes a first conducting ring disposed on an upper surface of said dielectric substrate and surrounding said sensing hole. The second conducting ring is disposed on a lower surface of the dielectric substrate and surrounds the sensing hole. The first sensor element and the second sensor are capable of producing a variable response when the first sensor element is disposed in the sensing hole.
    Type: Grant
    Filed: July 14, 2010
    Date of Patent: February 19, 2013
    Assignee: Amfit, Inc
    Inventors: James T. Walker, Christopher I. Walker, Tony G. Tadin, Arjen Sundman
  • Publication number: 20120264202
    Abstract: A printed circuit structure containing a fluidic chamber configured to receive an aqueous solution containing a sample to be analyzed and fluorophore for polymerase chain reaction analysis. The printed circuit structure also contains a heating element that provides for temperature cycling of the fluidic chamber to support polymerase chain reaction analysis.
    Type: Application
    Filed: March 19, 2012
    Publication date: October 18, 2012
    Inventors: Christopher I. WALKER, Aditya RAJAGOPAL
  • Patent number: 8232091
    Abstract: This invention provides a system for performing PCR, and real time PCR in particular with great speed and specificity. The system employs a heat block containing a liquid composition to rapidly transfer heat to and from reaction vessels. The system makes use of the reflective properties of the liquid metal to reflect signal from the PCR into the vessel and out the top. In this way, the signal can be measured by an optical assembly in real time without removing the vessels from the heat block.
    Type: Grant
    Filed: May 17, 2007
    Date of Patent: July 31, 2012
    Assignee: California Institute of Technology
    Inventors: George Maltezos, Matthew Johnston, David Goodwin, Axel Scherer, Christopher I. Walker
  • Publication number: 20120171678
    Abstract: This invention provides a system for performing PCR, and real time PCR in particular, with great speed and specificity. The system employs a heat block containing a liquid composition to rapidly transfer heat to and from reaction vessels. The system makes use of the reflective properties of the liquid metal to reflect signal from the PCR into the vessel and out the top. In this way, the signal can be measured by an optical assembly in real time without removing the vessels from the heat block.
    Type: Application
    Filed: March 9, 2012
    Publication date: July 5, 2012
    Applicant: California Institute of Technology
    Inventors: George MALTEZOS, Matthew JOHNSTON, David GOODWIN, Axel SCHERER, Christopher I. WALKER
  • Patent number: 8008046
    Abstract: This invention provides a method for carrying out nucleic acid amplification reactions involving heating and cooling of samples in sample vessels utilizing a heat block comprising a liquid. The method can be used to perform multiple nucleic acid amplification reactions simultaneously in which each of the reactions is performed so as to have temperature profiles. The apparatus can be used for performing PCR, and real time PCR in particular, with control and uniformity.
    Type: Grant
    Filed: December 15, 2008
    Date of Patent: August 30, 2011
    Assignee: California Institute of Technology
    Inventors: George Maltezos, Matthew Johnston, David Goodwin, Axel Scherer, Christopher I. Walker
  • Patent number: 8003370
    Abstract: This invention provides an apparatus for providing heating and cooling of samples in sample vessels having uniform temperature profiles. The apparatus can be used for performing PCR, and real time PCR in particular, with control and uniformity. The system employs a heat block containing a liquid composition to efficiently transfer heat to and from reaction vessels.
    Type: Grant
    Filed: December 15, 2008
    Date of Patent: August 23, 2011
    Assignee: California Institute of Technology
    Inventors: George Maltezos, Matthew Johnston, David Goodwin, Axel Scherer, Christopher I. Walker
  • Patent number: 7992587
    Abstract: By use of the vias a microfluidic autoregulator is fabricated comprising an origin of a fluid, a sink for the fluid, a main flow channel coupling the origin and the sink, a valve communicated to the main flow channel to selectively control flow of fluid therethrough, and means dependent on flow through the main flow channel for creating a pressure differential across the valve to at least partially activate the valve to control flow of fluid through the main flow channel. The means for dependent on flow for creating a pressure differential comprises either a dead-end detour channel from the flow channel to the valve, or a loop channel fed back to the control chamber of the valve.
    Type: Grant
    Filed: November 28, 2006
    Date of Patent: August 9, 2011
    Assignee: California Institute of Technology
    Inventors: Emil Kartalov, Axel Scherer, W. French Anderson, Christopher I. Walker
  • Publication number: 20110140705
    Abstract: An electrostatic sensor device including a first sensor element and a second sensor element; a dielectric substrate material formed in two layers, and a sensing hole which penetrates the dielectric substrate material from its upper surface to its lower surface. The first sensor element is receivable in the sensing hole; and second sensor element includes a first conducting ring disposed on an upper surface of said dielectric substrate and surrounding said sensing hole. The second conducting ring is disposed on a lower surface of the dielectric substrate and surrounds the sensing hole. The first sensor element and the second sensor are capable of producing a variable response when the first sensor element is disposed in the sensing hole.
    Type: Application
    Filed: July 14, 2010
    Publication date: June 16, 2011
    Inventors: James T. Walker, Christopher I. Walker, Tony G. Tadin, Arjen Sundman
  • Publication number: 20100309112
    Abstract: Pixel devices, comprising ink particles differing in electrical charge, mass and/or shape contained within a fluidic structure, and related arrays methods and systems.
    Type: Application
    Filed: June 8, 2010
    Publication date: December 9, 2010
    Inventors: Aditya Rajagopal, Christopher I. Walker, Saurabh Vyawahare, Axel Scherer, Thomas A. Tombrello
  • Patent number: 7777877
    Abstract: The invention provides a high efficiency coupling structure for extracting illumination such as fluorescent radiation from a chemical reaction vessel such as a cuvette. The cuvette is provided with a mirrored surface. An end cap for the cuvette includes a probe portion that exhibits total internal reflection. Lenses are provided in various embodiments that improve the light collection and directing properties of the end cap. A fast optical system for free space coupling of optical radiation emanating from a chemical processing cuvette that uses the end cap as an element is also described.
    Type: Grant
    Filed: October 22, 2007
    Date of Patent: August 17, 2010
    Assignee: California Institute of Technology
    Inventors: Christopher I. Walker, Axel Scherer
  • Publication number: 20100084371
    Abstract: Methods for fabrication of microfluidic systems on printed circuit boards (PCB) are described. The PCB contains layers of insulating material and a layer or layers of metal buried within layers of insulating material. The metal layers are etched away, leaving fully enclosed microfluidic channels buried within the layers of insulating material.
    Type: Application
    Filed: October 1, 2009
    Publication date: April 8, 2010
    Inventors: Christopher I. WALKER, Aditya Rajagopal, Axel Scherer
  • Publication number: 20090275014
    Abstract: This invention provides a method for carrying out nucleic acid amplification reactions involving heating and cooling of samples in sample vessels utilizing a heat block comprising a liquid. The method can be used to perform multiple nucleic acid amplification reactions simultaneously in which each of the reactions is performed so as to have temperature profiles. The apparatus can be used for performing PCR, and real time PCR in particular, with control and uniformity.
    Type: Application
    Filed: December 15, 2008
    Publication date: November 5, 2009
    Inventors: George MALTEZOS, Matthew Johnston, David Goodwin, Axel Scherer, Christopher I. Walker
  • Publication number: 20090275113
    Abstract: This invention provides an apparatus for providing heating and cooling of samples in sample vessels having uniform temperature profiles. The apparatus can be used for performing PCR, and real time PCR in particular, with control and uniformity. The system employs a heat block containing a liquid composition to efficiently transfer heat to and from reaction vessels.
    Type: Application
    Filed: December 15, 2008
    Publication date: November 5, 2009
    Inventors: George MALTEZOS, Matthew JOHNSTON, David GOODWIN, Axel SCHERER, Christopher I. WALKER