Patents Assigned to Sandia
  • Patent number: 5633527
    Abstract: A unitary lens semiconductor device and method. The unitary lens semiconductor device is provided with at least one semiconductor layer having a composition varying in the growth direction for unitarily forming one or more lenses in the semiconductor layer. Unitary lens semiconductor devices may be formed as light-processing devices such as microlenses, and as light-active devices such as light-emitting diodes, photodetectors, resonant-cavity light-emitting diodes, vertical-cavity surface-emitting lasers, and resonant cavity photodetectors.
    Type: Grant
    Filed: February 6, 1995
    Date of Patent: May 27, 1997
    Assignee: Sandia Corporation
    Inventor: Kevin L. Lear
  • Patent number: 5632703
    Abstract: An infinitely variable transmission is capable of operating between a maximum speed in one direction and a minimum speed in an opposite direction, including a zero output angular velocity, while being supplied with energy at a constant angular velocity. Input energy is divided between a first power path carrying an orbital set of elements and a second path that includes a variable speed adjustment mechanism. The second power path also connects with the orbital set of elements in such a way as to vary the rate of angular rotation thereof. The combined effects of power from the first and second power paths are combined and delivered to an output element by the orbital element set. The transmission can be designed to operate over a preselected ratio of forward to reverse output speeds.
    Type: Grant
    Filed: August 4, 1995
    Date of Patent: May 27, 1997
    Assignee: Sandia Corporation
    Inventors: Donald F. Wilkes, James W. Purvis, A. Keith Miller
  • Patent number: 5630413
    Abstract: This invention relates to methods and apparatus for, preferably, determining non-invasively and in vivo at least two of the five blood gas parameters (i.e., pH, [HCO.sub.3.sup.- ], PCO.sub.2, PO.sub.2, and O.sub.2 sat.) in a human.
    Type: Grant
    Filed: August 12, 1994
    Date of Patent: May 20, 1997
    Assignee: Sandia Corporation
    Inventors: Edward V. Thomas, Mark R. Robinson, David M. Haaland, Mary K. Alam
  • Patent number: 5630129
    Abstract: An application-level method for dynamically maintaining global load balance on a parallel computer, particularly on massively parallel MIMD computers. Global load balancing is achieved by overlapping neighborhoods of processors, where each neighborhood performs local load balancing. The method supports a large class of finite element and finite difference based applications and provides an automatic element management system to which applications are easily integrated.
    Type: Grant
    Filed: December 1, 1993
    Date of Patent: May 13, 1997
    Assignee: Sandia Corporation
    Inventor: Stephen R. Wheat
  • Patent number: 5626040
    Abstract: A discriminator apparatus and method that discriminates between a unique signal and any other (incorrect) signal. The unique signal is a sequence of events; each event can assume one of two possible event states. Given the unique signal, a maze wheel is allowed to rotate fully in one direction. Given an incorrect signal, both the maze wheel and a pin wheel lock in position.
    Type: Grant
    Filed: July 20, 1994
    Date of Patent: May 6, 1997
    Assignee: Sandia Corporation
    Inventor: Gilbert L. Benavides
  • Patent number: 5627929
    Abstract: An integrated optical XY coupler having two converging input waveguide arms meeting in a central section and a central output waveguide arm and two diverging flanking output waveguide arms emanating from the central section. In-phase light from the input arms constructively interfers in the central section to produce a single mode output in the central output arm with the rest of the light being collected in the flanking output arms. Crosstalk between devices on a substrate is minimized by this collection of the out-of-phase light by the flanking output arms of the XY coupler.
    Type: Grant
    Filed: May 4, 1995
    Date of Patent: May 6, 1997
    Assignee: Sandia Corporation
    Inventors: G. Allen Vawter, G. Ronald Hadley
  • Patent number: 5625635
    Abstract: An infrared emitting device and method. The infrared emitting device comprises a III-V compound semiconductor substrate upon which are grown a quantum-well active region having a plurality of quantum-well layers formed of a ternary alloy comprising InAsSb sandwiched between barrier layers formed of a ternary alloy having a smaller lattice constant and a larger energy bandgap than the quantum-well layers. The quantum-well layers are preferably compressively strained to increase the threshold energy for Auger recombination; and a method is provided for determining the preferred thickness for the quantum-well layers. Embodiments of the present invention are described having at least one cladding layer to increase the optical and carrier confinement in the active region, and to provide for waveguiding of the light generated within the active region.
    Type: Grant
    Filed: November 28, 1994
    Date of Patent: April 29, 1997
    Assignee: Sandia Corporation
    Inventors: Steven R. Kurtz, Robert M. Biefeld, L. Ralph Dawson, Arnold J. Howard, Kevin C. Baucom
  • Patent number: 5625288
    Abstract: Self-stressing test structures for realistic high frequency reliability characterizations. An on-chip high frequency oscillator, controlled by DC signals from off-chip, provides a range of high frequency pulses to test structures. The test structures provide information with regard to a variety of reliability failure mechanisms, including hot-carriers, electromigration, and oxide breakdown. The system is normally integrated at the wafer level to predict the failure mechanisms of the production integrated circuits on the same wafer.
    Type: Grant
    Filed: January 16, 1996
    Date of Patent: April 29, 1997
    Assignee: Sandia Corporation
    Inventors: Eric S. Snyder, David V. Campbell
  • Patent number: 5624529
    Abstract: A dry etching method. According to the present invention, a gaseous plasma comprising, at least in part, boron trichloride, methane, and hydrogen may be used for dry etching of a compound semiconductor material containing layers including aluminum, or indium, or both. Material layers of a compound semiconductor alloy such as AlGaInP or the like may be anisotropically etched for forming electronic devices including field-effect transistors and heterojunction bipolar transistors and for forming photonic devices including vertical-cavity surface-emitting lasers, edge-emitting lasers, and reflectance modulators.
    Type: Grant
    Filed: May 10, 1995
    Date of Patent: April 29, 1997
    Assignee: Sandia Corporation
    Inventors: Randy J. Shul, Christopher Constantine
  • Patent number: 5621751
    Abstract: An apparatus and method for controlling electrode gap in a vacuum arc remelting furnace, particularly at low melting currents. Spectrographic analysis is performed of the metal vapor plasma, from which estimates of electrode gap are derived.
    Type: Grant
    Filed: April 21, 1995
    Date of Patent: April 15, 1997
    Assignee: Sandia Corporation
    Inventors: Rodney L. Williamson, Frank J. Zanner, Stephen M. Grose
  • Patent number: 5612871
    Abstract: A quality monitoring system can detect certain system faults and fraud attempts in a distributed voting system. The system uses decoy voters to cast predetermined check ballots. Absent check ballots can indicate system faults. Altered check ballots can indicate attempts at counterfeiting votes. The system can also cast check ballots at predetermined times to provide another check on the distributed voting system.
    Type: Grant
    Filed: August 12, 1994
    Date of Patent: March 18, 1997
    Assignee: Sandia Corporation
    Inventor: David Skogmo
  • Patent number: 5607182
    Abstract: An apparatus and method for making a low cost, self-venting, inflatable protective cushion of simple and structurally efficient design with a shape and construction that optimizes the cushion's ability to withstand inflation pressures and impact when deployed which includes a sheet defined by at least one fold line and a plurality of flap portions, each flap portion having a base edge corresponding to a fold line and at least two side edges each extending outwardly from a base edge and ultimately converging to meet each other, the flap portions being folded at the fold line(s) and being joined at corresponding side edges to define an inflatable chamber. The inflatable protective cushion and method for making same may further include a lightweight, low permeability, fabric that optimizes the cushion's ability to withstand inflation pressures and impact when deployed and minimizes the packed volume of the cushion when stored.
    Type: Grant
    Filed: February 21, 1996
    Date of Patent: March 4, 1997
    Assignees: Sandia Corporation, Precision Fabrics Group, Inc.
    Inventors: James M. Nelsen, Larry D. Whinery, Kenneth W. Gwinn, Donald D. McBride, Daniel A. Luna, Joseph P. Holder, Richard J. Bliton
  • Patent number: 5602486
    Abstract: An apparatus and method for sensing impedances of materials placed in contact therewith. The invention comprises a plurality of drive electrodes and one or more sense electrodes. Both rotating electric fields and differently shaped electric fields are provided for, as are analysis of structure and composition at different orientations and depths.
    Type: Grant
    Filed: November 10, 1994
    Date of Patent: February 11, 1997
    Assignee: Sandia Corporation
    Inventor: James L. Novak
  • Patent number: 5596992
    Abstract: Multivariate classification techniques are applied to spectra from cell and tissue samples irradiated with infrared radiation to determine if the samples are normal or abnormal (cancerous). Mid and near infrared radiation can be used for in vivo and in vitro classifications using at least different wavelengths.
    Type: Grant
    Filed: June 30, 1993
    Date of Patent: January 28, 1997
    Assignee: Sandia Corporation
    Inventors: David M. Haaland, Howland D. T. Jones, Edward V. Thomas
  • Patent number: 5596254
    Abstract: A new class of coplanar two-axis angular effectors. These effectors combine a two-axis rotational joint analogous to a Cardan joint with linear actuators in a manner to produce a wider range of rotational motion about both axes defined by the joint. This new class of effectors also allows design of robotic manipulators having very high strength and efficiency. These effectors are particularly suited for remote operation in unknown surroundings, because of their extraordinary versatility. An immediate application is to the problems which arise in nuclear waste remediation.
    Type: Grant
    Filed: August 12, 1994
    Date of Patent: January 21, 1997
    Assignee: Sandia Corporation
    Inventors: Mark R. Vaughn, Rush D. Robinett, III, John R. Phelan, Don M. Van Zuiden
  • Patent number: 5589396
    Abstract: Coatings and sensors having both steric and chemical selectivity. Controlled porosity provides the steric selectivity, whereas chemically tailored film properties, using controlled composition or modification by coupling agents, chemical species replacement, or chemical species within pores, provide the chemical selectivity. Single or multiple layers may be provided.
    Type: Grant
    Filed: February 1, 1993
    Date of Patent: December 31, 1996
    Assignee: Sandia Corporation
    Inventors: Gregory C. Frye, C. Jeffrey Brinker, Daniel H. Doughty, Thomas Bein, Karin Moller
  • Patent number: 5587922
    Abstract: A method of and apparatus for graph partitioning involving the use of a plurality of eigenvectors of the Laplacian matrix of the graph of the problem for which load balancing is desired. The invention is particularly useful for optimizing parallel computer processing of a problem and for minimizing total pathway lengths of integrated circuits in the design stage.
    Type: Grant
    Filed: July 15, 1996
    Date of Patent: December 24, 1996
    Assignee: Sandia Corporation
    Inventors: Bruce A. Hendrickson, Robert W. Leland
  • Patent number: 5571944
    Abstract: Moisture corrosive gas stream is measured as a function of the difference in resonant frequencies between two acoustic wave (AW) devices, each with a film which accepts at least one of the components of the gas stream. One AW is located in the gas stream while the other is located outside the gas stream but in the same thermal environment. In one embodiment, the film is a hydrophilic material such as SiO.sub.2. In another embodiment, the SiO.sub.2 is covered with another film which is impermeable to the corrosive gas, such that the AW device in the gas stream measures only the water vapor. In yet another embodiment, the film comprises polyethylene oxide which is hydrophobic and measures only the partial pressure of the corrosive gas. Other embodiments allow for compensation of drift in the system.
    Type: Grant
    Filed: December 20, 1994
    Date of Patent: November 5, 1996
    Assignee: Sandia Corporation
    Inventors: Kent B. Pfeifer, Gregory C. Frye, Thomas W. Schneider
  • Patent number: 5568499
    Abstract: A compound-semiconductor optical device and method. The optical device is provided with one or more asymmetrically-graded heterojunctions between compound semiconductor layers for forming a distributed Bragg reflector mirror having an improved electrical and thermal resistance. Efficient light-emitting devices such as light-emitting diodes, resonant-cavity light-emitting diodes, and vertical-cavity surface-emitting lasers may be formed according to the present invention, which may be applied to the formation of resonant-cavity photodetectors.
    Type: Grant
    Filed: April 7, 1995
    Date of Patent: October 22, 1996
    Assignee: Sandia Corporation
    Inventor: Kevin L. Lear
  • Patent number: 5568506
    Abstract: A system for controlling electrode gap in an electro-slag remelt furnace has a constant regulated voltage and an eletrode which is fed into the slag pool at a constant rate. The impedance of the circuit through the slag pool is directly proportional to the gap distance. Because of the constant voltage, the system current changes are inversely proportional to changes in gap. This negative feedback causes the gap to remain stable.
    Type: Grant
    Filed: May 16, 1995
    Date of Patent: October 22, 1996
    Assignee: Sandia Corporation
    Inventor: Max E. Schlienger