Patents by Inventor Clifford G. Walker

Clifford G. 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: 4637726
    Abstract: A wafer is positioned in a magnetic field. A computer initializes the light level and the electronic gain of each detector preamp associated with a fiber optic link from the analyzer. The magnetic field direction would then be reversed by computer command. This would cause a localized change in intensity of light passing through the wafer, due to Faraday Rotation (FR). The resulting change in detector output together with location and wavelength data could be used to compute a map of the wafer.
    Type: Grant
    Filed: February 7, 1985
    Date of Patent: January 20, 1987
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Clifford G. Walker, George A. Tanton
  • Patent number: 4635482
    Abstract: In a Sagnac-type of laser accelerometer, a common waveguide transducing element has oppositely rotating optical beams therein which are subsequently combined in a detection circuit to provide an output indicative of acceleration perpendicular to the plane of the transducing element. The counter rotating beams are ninety degrees polarized while passing through the transducer, so that only one beam is affected by the stress forces. The beams are shifted to the same polarization before interference fringes are developed on the detector.
    Type: Grant
    Filed: August 5, 1985
    Date of Patent: January 13, 1987
    Inventor: Clifford G. Walker
  • Patent number: 4529876
    Abstract: A transducer utilizes a laser source, photoelastic waveguides, two optical beam paths and a detector for processing optical energy from the laser through a stress transfer medium and thereby detects stress forces present on the transducer. This allows forces such as pressure, strain, voltage, or current to be detected and converted from one form to another for measurement of the force and response thereto. Input forces are detected as optical frequency shifts and converted to electrical signal outputs for indicating circuitry. In an integrated optic format, the transducer package volume is small, allowing ready use in guidance or navigation systems. Light generated by the laser travels along two paths, is optically stressed by the force transfer member and is combined with a reference signal to obtain the stress intelligence.
    Type: Grant
    Filed: December 27, 1983
    Date of Patent: July 16, 1985
    Inventor: Clifford G. Walker
  • Patent number: 4454418
    Abstract: A transducer utilizes a laser source, photoelastic waveguides, two optical beam paths and detectors for processing optical energy from the laser through a stress transfer medium and thereby detects stress forces present on the transducer. This allows forces such as pressure, strain, voltage, or current to be detected and converted from one form to another for measurement of the force and response thereto. Input forces are detected as optical frequency shifts and converted to electrical signal outputs for indicating circuitry. In an integrated optic format, the transducer package volume is small, allowing ready use in guidance or navigation systems. Light generated by the laser travels along two paths, is optically stressed by the force transfer member and is either combined or compared with a reference signal to obtain the stress intelligence.
    Type: Grant
    Filed: April 26, 1982
    Date of Patent: June 12, 1984
    Inventor: Clifford G. Walker
  • Patent number: 4429573
    Abstract: A dual function device measures both inertial acceleration and rotation rate using a common birefringent ring resonator. A beam from a laser source is split, forming two orthogonally polarized beams which are coupled through respective Bragg cells and into a common waveguide. The beams are subsequently coupled into a ring resonator waveguide which has a proof-mass disposed thereon for applying acceleration forces to the resonator. Acceleration is measured when forces stress the proof-mass, detuning the cavity with respect to the horizontally polarized wave and thereby affecting output energy coupled therefrom. Similarly, rotation is measured when there is a rotation rate in the plane of the waveguide, which detunes the cavity with respect to the vertically polarized beam. Output energy from the waveguide cavity is used to indicate the degree of acceleration and/or rotation and to provide feedback for restoring resonance.
    Type: Grant
    Filed: June 29, 1982
    Date of Patent: February 7, 1984
    Inventor: Clifford G. Walker
  • Patent number: 4428234
    Abstract: An accelerometer utilizes a laser source, a photoelastic waveguide, a plurality of optical beam paths and detectors for processing optical output energy from the laser along two or more paths for providing phase detection for measuring acceleration. An electronic signal processing section converts the optical signals to electrical signals and provides an output for indicating circuitry. Formed in a micro-optical/integrated optic format, the accelerometer can be packaged in a small volume which allows ready use in systems for guidance or navigation purposes. Light generated by the laser is divided into two or four beam paths. Beam energy is directed through the photo-elastic waveguides and are selectively recombined to set up interference conditions. Subjecting the waveguide to acceleration stress will cause a detectable phase difference to occur which is indicative of acceleration.
    Type: Grant
    Filed: March 25, 1982
    Date of Patent: January 31, 1984
    Inventor: Clifford G. Walker
  • Patent number: 4422331
    Abstract: A laser accelerometer produces an output, phase modulated beam which is polarized in a direction perpendicular to the direction from which acceleration forces are applied. In the accelerometer a laser beam is directed through a resonant cavity toward a detector. A proof mass disposed adjacent the cavity, stresses the cavity in response to acceleration force. Acceleration detunes the cavity. Detected changes in the cavity output results in a feedback voltage change being coupled to the cavity and to an output detector. This change in voltage to restore cavity resonance is proportional to the input acceleration.
    Type: Grant
    Filed: April 2, 1982
    Date of Patent: December 27, 1983
    Inventor: Clifford G. Walker
  • Patent number: 4332090
    Abstract: An inclinometer which employs a laser light source with a transparent liq and a gas and the laws of optics to reflect the light source to a detector which provides signals for measuring the tilt angle and the direction of tilt from the local horizontal.
    Type: Grant
    Filed: February 7, 1980
    Date of Patent: June 1, 1982
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Escar L. Bailey, Clifford G. Walker
  • Patent number: 4315693
    Abstract: An optical strapdown inertial system using passive laser gyros and passive laser accelerometers and a computer. These components may be disposed on "chips" in integrated optics format to provide an all solid-state system having no moving parts.
    Type: Grant
    Filed: December 31, 1979
    Date of Patent: February 16, 1982
    Inventor: Clifford G. Walker
  • Patent number: 4307516
    Abstract: A directional two-axis differential optical inclinometer which includes lt sources and optical detectors in two different systems for determining angle change in a test table and the direction of change from the horizontal plane.
    Type: Grant
    Filed: February 7, 1980
    Date of Patent: December 29, 1981
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventor: Clifford G. Walker
  • Patent number: 4233847
    Abstract: An accelerometer utilizing a laser source and a resonant cavity formed by a pair of spaced mirrors. A birefringent isotropic material is disposed in the resonant cavity. Light generated by the laser is reflected back and forth between the mirrors and through the birefringent material to generate a pair of orthogonally polarized beams. The optical path of one beam is changed in response to acceleration forces acting on a proof mass carried on the birefringent material. The pair of beams produced have different phases. The phase difference will be by an amount proportional to the difference in refractive indexes along and perpendicular to the optic axis of the birefringent material.
    Type: Grant
    Filed: July 2, 1979
    Date of Patent: November 18, 1980
    Inventor: Clifford G. Walker
  • Patent number: H101
    Abstract: The two-color focal plane array detects a target or image a target in the traviolet (UV) and infrared (IR) simultaneously. The system is a correlation, contrast or moving target tracker with very good countermeasure capability against a ground, sea, or airborne target. The tracker/seeker can be an all solid state no-moving parts configuration with the two focal plane devices of detectors aligned in their layer so as to be at an effectively cofocal.
    Type: Grant
    Filed: October 1, 1984
    Date of Patent: August 5, 1986
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventor: Clifford G. Walker