Patents Assigned to Litton System, Inc.
  • Patent number: 5434505
    Abstract: To screen or test the electrical properties of HEMT-like wafers for their quality, the critical layer qualities of a wafer (16) are evaluated by measuring its conductivity (sigma or s) and mobility (mu or m) at upper and lower temperatures, which need only be sufficiently different as to remove uncertainties in the test data but, in practice, are room and liquid nitrogen temperatures. Novel equations show (1) that the crucial quality or merit factor (n.sub.s) the electron sheet density of two-dimensional electron gas (2DEG), can be determined by measuring the total layer conductivity (sigma or s) at the lower or liquid nitrogen temperature and mobility (mu or m) at the upper or room temperature and (2) by measuring overall layer effective mobility (mu or m) at both room and liquid nitrogen (the upper and lower) temperatures to provide a means to measure the value of the 2DEG density, n.sub.s which has better accuracy then where the temperature of mobility is only made at room temperature.
    Type: Grant
    Filed: July 30, 1993
    Date of Patent: July 18, 1995
    Assignee: Litton Systems, Inc.
    Inventor: Yi-Ching Pao
  • Patent number: 5434697
    Abstract: A deformable mirror system comprises a reflective face sheet, substrate, positioned behind the face sheet, having actuator bore holes extending entirely through the substrate. Actuator assemblies for deforming the face sheet are positioned in a different ones of the actuator bore holes and are bonded to both a back surface of the face sheet and to the substrate. The actuator assemblies each comprise a tile bonded to a back surface of the substrate to close a distal end of the actuator bore hole and an actuator bonded to the tiles, extending through the bore hole, and bonded to the face sheet near a proximal end of the bore hole. These assemblies can then be individually removed by destroying the adhesive quality of these bonds.
    Type: Grant
    Filed: July 27, 1994
    Date of Patent: July 18, 1995
    Assignee: Litton Systems, Inc.
    Inventor: George A. Ameer
  • Patent number: 5434704
    Abstract: A night vision sight is provided for use with a weapon, which includes an objective lens and a non-inverting image intensifier tube disposed along an optical axis, providing an intensified target image. The sight is focused by direct movement of the image intensifier tube relative to the fixed position of the objective lens. A reticle projector is disposed orthogonal to the optical axis and provides a collimated reticle image, the reticle image providing an aiming point for the weapon. The reticle image is superimposed over the target image, which are reflected into an eyepiece of the sight. The eyepiece has an axis between the optical axis and a sight line passing through a pre-existing sight provided with the weapon. Adjustment of the apparent position of the reticle to compensate for azimuth and elevation is accomplished by moving the reticle projector about crossed cylindrical bearings.
    Type: Grant
    Filed: August 14, 1992
    Date of Patent: July 18, 1995
    Assignee: Litton Systems, Inc.
    Inventors: Clifford J. Connors, Gary A. Wannagot, Roland M. Morley
  • Patent number: 5433640
    Abstract: An improved low power pulsed anode magnetron is provided having a cylindrical cathode centrally disposed within a plurality of radial anode vanes. An interaction region is provided between the surface of the cathode and the anode vane tips. A ratio of the anode-to-cathode space over the center-to-center distance between adjacent vane tips is within a range between 0.95 and 1.05. The cathode is joined to a magnetic polepiece assembly which channels magnetic flux to the interaction region. Both the cathode and the polepiece are mechanically adjustable from external to the magnetron to reposition the cathode and polepiece with respect to the anode vanes. The cathode surface is formed from an active nickel alloy which is cleaned by a chemical process followed by a high temperature and vacuum firing. An emissive surface is applied over the cleaned cathode surface.
    Type: Grant
    Filed: May 23, 1994
    Date of Patent: July 18, 1995
    Assignee: Litton Systems, Inc.
    Inventor: Gregory T. Schaeffer
  • Patent number: 5432889
    Abstract: A vector neural network (VNN) of interconnected neurons is provided in transition mappings of potential targets wherein the threshold (energy) of a single frame does not provide adequate information (energy) to declare a target position. The VNN enhances the signal-to-noise ratio (SNR) by integrating target energy over multiple frames including the steps of postulating massive numbers of target tracks (the hypotheses), propagating these target tracks over multiple frames, and accommodating different velocity targets by pixel quantization. The VNN then defers thresholding to subsequent target stages when higher SNR's are prevalent so that the loss of target information is minimized, and the VNN can declare both target location and velocity. The VNN can further include target maneuver detection by a process of energy balancing hypotheses.
    Type: Grant
    Filed: November 30, 1992
    Date of Patent: July 11, 1995
    Assignee: Litton Systems, Inc.
    Inventors: Leon K. Ekchian, David D. Johnson, William F. Smith
  • Patent number: 5432604
    Abstract: A ring laser gyroscope has an electrically insulating barrier ring placed between the grounded metal mounting device and the frame, which is formed of a lithium aluminosilicate material that contains mobile ions. The barrier ring prevents migration of the ions from the frame material to the mirrors that are used to direct the counterpropagating waves around the closed path in the ring laser gyroscope.
    Type: Grant
    Filed: March 9, 1993
    Date of Patent: July 11, 1995
    Assignee: Litton Systems, Inc.
    Inventors: John M. Canfield, Charles H. Volk, James D. Assendrup, Christine E. Geosling, Ann T. Nicol
  • Patent number: 5430574
    Abstract: The rugged filter/switch cavity includes at least a two section low thermal expansion glass tubular frame, each section with a highly polished edge for abutting engagement and rigid gripping by electrostatic attraction to maintain the cavity integrity. Each frame section supports a multi-layer low loss thin film mirror in opposing relation to define the cavity gap. One mirror is fixed in the first section and the other mirror is carried by a diaphragm portion of the other section for axial movement toward and away from the first mirror to tune the cavity to different frequencies. Coaxially aligned optical fibers, affixed to each section by flexible epoxy, guide light from a broadband source including, one or more signals, into the first section, through the first mirror and back and forth between mirrors until the cavity is resonant to a signal to be selected which signal then exits the cavity via the second mirror and the other optical fiber.
    Type: Grant
    Filed: July 25, 1994
    Date of Patent: July 4, 1995
    Assignee: Litton Systems, Inc.
    Inventor: Mohammad M. Tehrani
  • Patent number: 5428995
    Abstract: A sensor for measuring angular rotation rates about three orthogonal axes is based upon sensing Coriolis acceleration forces with a pair of nearly-identical rotors coupled coaxialy by a torsion spring and counter-oscillating in rotation. The torsional oscillator is mounted within a case by means of radial vanes, each comprisig two piezoelectric ceramic plates bonded to a thin metal core responsive to drive signals and providing rotational vibration isolation. The arms of the rotors are designed as piezoelectric open loop accelerometers. Electrodes of selected configurations are mounted to the outer surfaces of the planar members to collect charge indicative of Coriolis accelerations proportional to the angular rotations about the orthogonal axes.
    Type: Grant
    Filed: March 8, 1993
    Date of Patent: July 4, 1995
    Assignee: Litton Systems, Inc.
    Inventors: Samuel N. Fersht, Stanley F. Wyse, Robert E. Stewart, Samuel G. Miller
  • Patent number: 5428996
    Abstract: An integrated accelerometer includes hinges of silicon composition for securing the strut legs of a pendulous mass to the accelerometer body. Both the body of the accelerometer and the pendulous mass are of metal-coated compositions. Metallized pads are provided on selected surfaces of the hinges for forming eutectic bonds with the body and struts of the pendulous mass of the accelerometer. A heavily-doped continuous region adjacent the surface of the hinge connects the eutectic bonds through a flexure region of reduced thickness to complete necessary device circuitry.
    Type: Grant
    Filed: January 24, 1994
    Date of Patent: July 4, 1995
    Assignee: Litton Systems, Inc.
    Inventors: Henry C. Abbink, James W. Engel, Dean H. Lodwig, Robert E. Stewart
  • Patent number: 5428700
    Abstract: The wavelength of a light source (e.g., laser) is stabilized by introducing a collimated beam from the source into a "wedged" etalon, i.e., an etalon having a Fabry-Perot cavity that continuously decreases in width along at least one axis that is normal to the axis of beam propagation. A pair of photodetectors at the output side of the etalon detect respective portions of the beam traversing different cavity widths. The respective output signals of the photodetectors are employed in a feedback loop, whereby the wavelength of the light source is controlled so as to minimize the amplitude difference between the two photodetector signals. The wavelength of the light source can be tuned by varying the ratio of the amplitudes of the photodetector output signals. The wedged etalon can also be used as a multi-channel optical receiver, wherein a multi-wavelength collimated incident beam is introduced into the etalon.
    Type: Grant
    Filed: July 29, 1994
    Date of Patent: June 27, 1995
    Assignee: Litton Systems, Inc.
    Inventor: David B. Hall
  • Patent number: 5424827
    Abstract: An optical system and a method for separating overlapping spectra from a diffraction grating and an imaging spectrometer with increased free spectral range are disclosed. The light from a diffraction grating consists of multiple spectra overlapping each other and displaced along a spectral axis. The invention directs the light from the grating to a refractive element such, as a prism. The prism further disperses the light along the same spectral axis. The individual spectra are sufficiently displaced such that they no longer interfere with each other.
    Type: Grant
    Filed: April 30, 1993
    Date of Patent: June 13, 1995
    Assignee: Litton Systems, Inc.
    Inventors: Bruce A. Horwitz, Steven J. Wein
  • Patent number: 5423692
    Abstract: A single-pole electrical connector adapted for carrying high electrical current comprises a conductive receptacle member adapted to be coupled to an electrical cable; a conductive plug member adapted to be coupled to an electrical cable; said receptacle member incorporating a pin contact portion; said pin contact portion comprising a rod-like member; said plug member incorporating a socket contact portion; said receptacle member and said plug member being adapted for sliding mechanical engagement along a common longitudinal axis; said rod-like member having an external diameter slightly larger than the diameter of said socket contact portion being provided with at least one pair of resilient finger members formed by fabricating at least one diametrically extending slot thereacross; each of said finger members extends radially outwardly with respect to the longitudinal axis of said pin contact portion as a result of the formation of said slot, whereby the external diameter of a pair of opposite finger members
    Type: Grant
    Filed: November 5, 1993
    Date of Patent: June 13, 1995
    Assignee: Litton Systems, Inc.
    Inventor: Leonard J. Francis
  • Patent number: 5422817
    Abstract: Sculling error correction means, using third or higher order correction to correct for sculling errors in apparatus for converting angle measuring and acceleration measuring signals from a vehicle set of coordinates into a stabilized set of navigation coordinates.
    Type: Grant
    Filed: August 13, 1991
    Date of Patent: June 6, 1995
    Assignee: Litton Systems, Inc.
    Inventors: Daniel A. Tazartes, John G. Mark
  • Patent number: 5422542
    Abstract: An improved low power pulsed anode magnetron is provided having a cylindrical cathode centrally disposed within a plurality of radial anode vanes. An interaction region is provided between the surface of the cathode and the anode vane tips. A ratio of the anode-to-cathode space over the center-to-center distance between adjacent vane tips is within a range between 0.95 and 1.05. The cathode is joined to a magnetic polepiece assembly which channels magnetic flux to the interaction region. Both the cathode and the polepiece are mechanically adjustable from external to the magnetron to reposition the cathode and polepiece with respect to the anode vanes. The cathode surface is formed from an active nickel alloy which is cleaned by a chemical process followed by a high temperature and vacuum firing. An emissive surface is applied over the cleaned cathode surface.
    Type: Grant
    Filed: February 9, 1993
    Date of Patent: June 6, 1995
    Assignee: Litton Systems, Inc.
    Inventor: Gregory T. Schaeffer
  • Patent number: 5420478
    Abstract: A depressed collector is provided which is capable of recovering energy from a large orbit gyrating electron beam received from a microwave device, such as a gyrotron. The depressed collector sorts and collects the electrons of the spent electron beam on the basis of their radial energy levels. The depressed collector comprises a plurality of stages of electrodes. Each of the electrode stages have a negative potential applied thereto, with the first of the electrode stages having the greatest negative potential with respect to the microwave device, and the subsequent stages having decreasing relative potential. The depressed collector will sort the electrons from the gyrating electron beam in accordance with their radial energy, with electrons having the highest radial energy being collected on the first electrode, and electrons having lesser amounts of radial energy being collected on the subsequent electrodes.
    Type: Grant
    Filed: February 12, 1993
    Date of Patent: May 30, 1995
    Assignee: Litton Systems, Inc.
    Inventor: Glenn P. Scheitrum
  • Patent number: 5420683
    Abstract: Multioscillator beam-combining optics having prisms for processing both clockwise and anticlockwise elliptically polarized beams having both helicities transmitted through a partly transmissive corner mirror. The optical structure uses a thin-film polarizer with a waveplate which is not necessarily a quarter wave plate. Further, the waveplate thickness is determined so that one component of elliptically polarized light is converted into a linearly polarized beam. A thin film polarizer then blocks the linearly polarized beam. The waveplate principal crystal axes form a nominally forty five degree angle with the s and p polarization axes. Techniques are used to keep extraneous birefringence of the beams to a minimum.
    Type: Grant
    Filed: October 1, 1987
    Date of Patent: May 30, 1995
    Assignee: Litton Systems, Inc.
    Inventor: David B. Hall
  • Patent number: 5418507
    Abstract: A nonreciprocally coupled ferrimagnetic band reject and bandpass filter having passbands from 2-18 GHz and 6-18 GHz respectively. The band reject filter comprises one or more ferrimagnetic spheres shielded from each other by placement in nonmagnetic, electrically conductive cavities in a block placed in the flux gap of a tuning magnet. Nonreciprocal coupling is achieved by using full RF coupling loops and establishing all factors that affect the transmission line delay for travel of signals from one point in the filter to another such as loop length and size, cavity size, sphere size and spacing, dielectric constant, RF coupling loop wire size and spacing etc. such that the effective electrical length from the center of one full RF coupling loop to the centerline of the neighboring RF coupling loop is 1/4 wavelength, i.e.
    Type: Grant
    Filed: October 8, 1992
    Date of Patent: May 23, 1995
    Assignee: Litton Systems, Inc.
    Inventors: William J. Keane, Christopher F. Schiebold, Dirk M. Hoekstra
  • Patent number: 5418427
    Abstract: The present invention provides a double helix coupled vane forward wave crossed-field amplifier utilizing individually cooled vanes in the RF slow-wave circuit. Specifically, a double helix coupled vane is machined to create a channel in the shape of a "U" on one side of the vane. A vane coolant tube formed in a corresponding U-shape is inserted and brazed to the machined vane. The vane assembly is then attached to the anode body of which the backwall has holes formed to accept the coolant tubes from each vane. Divided backwall coolant channels are brazed to the outside of the anode, thereby placing in fluid communication the coolant channels to the vane coolant tube. Accordingly, coolant is cycled through each vane tube and individual vanes of the anode are thus cooled.
    Type: Grant
    Filed: May 28, 1992
    Date of Patent: May 23, 1995
    Assignee: Litton Systems, Inc.
    Inventors: John C. Cipolla, Chris L. Wheeland, Guilford R. MacPhail, Joseph C. Musheno, James L. Barry
  • Patent number: 5414741
    Abstract: A low phase noise third order phase lock loop which can track and eliminate microphonic disturbances and phase hits. The PLL utilizes a third order loop filter which incorporates two integrators. These two integrators, when coupled with the integration which occurs at the voltage control input of the voltage controlled oscillator within the PLL yield an open loop transfer function with a --18 dB/octave rolloff over a band of frequencies which at least encompasses the spectral content of the microphonic or phase hit phase noise disturbance to be eliminated. The open loop gain of the phase lock loop must be set high enough such that the phase lock loop does not oscillate and such that the loop converges and locks. The integrators are implemented with operational amplifiers with RC feedback networks. The values of the components in the RC feedback networks set the frequencies of two zeroes in the transfer function.
    Type: Grant
    Filed: October 14, 1993
    Date of Patent: May 9, 1995
    Assignee: Litton Systems, Inc.
    Inventor: Kent K. Johnson
  • Patent number: D358830
    Type: Grant
    Filed: March 30, 1994
    Date of Patent: May 30, 1995
    Assignee: Litton Systems, Inc.
    Inventor: Amotz Dor