Patents Assigned to Thomson
  • Patent number: 4740772
    Abstract: The object of the invention is an improved gradient coil. The improvement consists in making steps in the saddle-shaped conductors that form the coil in order to modify local distortions in the magnetic field produced. It is shown that the correction thus made has little effect on the rest of the field of distribution.
    Type: Grant
    Filed: October 15, 1986
    Date of Patent: April 26, 1988
    Assignee: Thomson-CGR
    Inventor: Claude Prevot
  • Patent number: 4740789
    Abstract: A method for optimizing the storage of video signals in a digital scan converter provided with an intermediate block memory provided between the radial memory and the image memory. In the block memory, the pixels to be displayed are grouped together in blocks, the blocks being transferred in parallel to the image memory when they are completely filled. The blocks of the block memory correspond to those of the image memory and can each be used several times during a single antenna revolution.
    Type: Grant
    Filed: January 30, 1987
    Date of Patent: April 26, 1988
    Assignee: Thomson-CSF
    Inventors: Jean-Claude Henri, Jean-Pierre Andrieu, Dominique Gault
  • Patent number: 4741014
    Abstract: A radiological installation for front and profile examinations using a single image receiver. The receiver is fixed to a transverse arm with respect to the table by means of a rotation shaft which may be locked in at least two predetermined positions, said arm forming part of a mobile support movable along said table.
    Type: Grant
    Filed: December 21, 1984
    Date of Patent: April 26, 1988
    Assignee: Thomson-CGR
    Inventor: Pierre C. Lajus
  • Patent number: 4739330
    Abstract: A frequency modulation radio altimeter has a directional antenna which is connected to a transmission-reception switch controlled by a signal generator. The generator delivers periodic signals whose recurrence period is proportional to the delay time of the ground echo. The transmitter includes a radio frequency modulator modulated in frequency by a saw tooth signal whose recurrence period is proportional to the delay time of the ground echo. A homodyne receiver includes circuits for acquiring and tracking the ground echo signal, and supplies an output signal representative of the altitude and a control signal which is supplied to the inputs controlling the recurrence period of the transmission modulator and of the generator controlling the transmission-reception switch.
    Type: Grant
    Filed: June 19, 1985
    Date of Patent: April 19, 1988
    Assignee: Thomson-CSF
    Inventor: Michel Lazarus
  • Patent number: 4739267
    Abstract: Calibration of radiofrequency excitation involves application of two successive pulses of identical waveform and amplitude. The excitations are applied in series of excitations of variable amplitude from one excitation to the next in order to determine the calibrated value of the excitation pulses to be employed by transition of the amplitude of the received signal through a minimum value. It is demonstrated that this procedure prevents the calibration from being impaired by inhomogeneities of the orienting field of the apparatus. Spatial and spectral inhomogeneities of the excitation are also eliminated by applying throughout the calibration a selection gradient to the body under examination. Defects are eliminated by frequency filtering of the detected signal.
    Type: Grant
    Filed: May 4, 1987
    Date of Patent: April 19, 1988
    Assignee: Thomson-CGR
    Inventors: Patrick Leroux, Alain Marilier
  • Patent number: 4739306
    Abstract: A calibrated-weight balance for converting an electrical analog signal to a binary signal as applicable to flash-type analog-to-digital converters is composed of a bistable multivibrator having two transistors (15, 16) and two resistors (25, 26). In the reference channel (15, 25), a current I.sub.0 flows through a resistor (27) connected between drain and ground. In the measuring channel (16, 26), a transistor (17) is connected between a reference voltage (-V.sub.ref) and the drain of the measuring transistor (16). The input of the balance (V.sub.E) is the gate of the third transistor (17). The outputs (Q, Q) of the balance are the drains of the first and second transistors (15, 16). The resistor (26) for supplying the second transistor (16) constitutes the calibrated weight and permits the flow of a current which is a multiple of the current which flows through the resistor (27) of the reference channel.
    Type: Grant
    Filed: November 7, 1986
    Date of Patent: April 19, 1988
    Assignee: Thomson-CSF
    Inventor: Pham N. Tung
  • Patent number: 4738683
    Abstract: In order to fabricate gates for an integrated circuit formed on a semiconductor substrate of silicon covered with at least one layer of oxide, one layer of polycrystalline silicon and if necessary one layer of silicide, an initial step consists in successive deposition of a silicon nitride layer and a silicon oxide layer, openings in these two layers being then formed by photoetching in a second step. In a third step, the silicon oxide layer is partly removed by deoxidation in order to bare the nitride layer over a certain distance which determines the spacing between two consecutive gates, oxide being then grown within the openings formed during the second step. The final step consists in removing the nitride regions uncovered during the third step as well as the subjacent silicide layer if this latter is provided and the subjacent polycrystalline silicon layer.
    Type: Grant
    Filed: October 30, 1985
    Date of Patent: April 19, 1988
    Assignee: Thomson-CSF
    Inventors: Pierre Blanchard, Jean P. Cortot
  • Patent number: 4739308
    Abstract: The formatting/unformatting device of the invention especially comprises a formatting device made up of a justifier linked to an input register, the output of which is linked, through a multiplexer, to the residue input of the justifier as well as to a first intermediate register through another multiplexer and to another multiplexer. The latter multiplexer is linked to a second intermediate register and an output multiplexer, the output of which is linked to an output register which acts as a buffer for the bulk memory.
    Type: Grant
    Filed: January 12, 1987
    Date of Patent: April 19, 1988
    Assignee: Thomson-CGR
    Inventor: Jean Lienard
  • Patent number: 4739269
    Abstract: An orbit antenna for a nuclear magnetic resonance (NMR) imaging apparatus is symmetrized by joining together two concentric conductive loops in series. The antenna is frequency-tuned by a capacitor placed in parallel between the non-interconnected ends of the loops. A receiving circuit having a high input impedance is connected between the midpoint of the loops and one of the capacitor terminals. It is thus shown that the antenna is not unbalanced and endows the received signal with all the advantages of symmetrized antennas.
    Type: Grant
    Filed: January 5, 1987
    Date of Patent: April 19, 1988
    Assignee: Thomson-CGR
    Inventor: Jean P. Kopp
  • Patent number: 4737724
    Abstract: A variable digital phase-shifter comprises a variable-propagation-time phase corrector consisting of a nonrecursive transversal digital filter having a predetermined even number N of coefficients. The filter is coupled with an amplitude corrector consisting of a nonrecursive transversal digital bandpass filter with an odd number of coefficients, a multiplier and a summing circuit for correcting the variations in gain of the phase corrector in order to obtain an approximately constant overall gain of the variable digital phase-shifter.
    Type: Grant
    Filed: May 20, 1986
    Date of Patent: April 12, 1988
    Assignee: Thomson Video Equipment
    Inventor: Pascal Porrot
  • Patent number: 4736234
    Abstract: In a light image detector, a substrate is covered with a first layer of conductive material on which is formed a two-dimensional matrix array of photodiodes in the form of pads arranged in rows and columns and each comprising a layer of amorphous semiconductor material doped with a predetermined type (n-type or p-type), a layer of undoped amorphous semiconductor material, a layer of amorphous semiconductor material doped with another predetermined type (n-type or p-type), a second layer of conductive material, each photodiode being insulated from adjacent photodiodes by means of insulating material. On the insulating material, columns of material are disposed along the columns of photodiodes and are each formed by a layer of metallic material and a layer of doped amorphous semiconductor material.
    Type: Grant
    Filed: July 16, 1986
    Date of Patent: April 5, 1988
    Assignee: Thomson-CSF
    Inventors: Francois Boulitrop, Eric Chartier, Nicolas Szydlo, Bernard Hepp, Nicole Proust
  • Patent number: 4736235
    Abstract: A diode structure having connections utilizing beam leads as disclosed wherein two beam-leads are spaced apart by a diode chip and by a glass stud which is spaced away from the diode chip. Contacts are taken from the diode on its two main faces. One of the two lead-beams is formed in two separated parts in order to provide for an assembly of two metal portions and of a glass stud which forms three adjustable coupling capacitors.
    Type: Grant
    Filed: August 20, 1986
    Date of Patent: April 5, 1988
    Assignee: Thomson-CSF
    Inventor: Raymond Henry
  • Patent number: 4736176
    Abstract: A structure is provided for connection between Bitter coils in a magnet with homogeneous field. The magnet is formed of several Bitter coils joined side by side and whose disks are of different thicknesses and two adjacent coils are connected together by a transition disk forming a turn and having for example a set-back on each of its faces for adapting it to the different thicknesses of the disks of two coils.
    Type: Grant
    Filed: November 14, 1986
    Date of Patent: April 5, 1988
    Assignee: Thomson-CGR
    Inventor: Guy Aubert
  • Patent number: 4735353
    Abstract: A method of friction welding comprising causing relative rotation between a pair of workpieces by actuating first and second drive means, the first drive means being coupled to a primary source of energy, and the second drive means being adapted to store auxiliary energy; bringing the workpieces into contact with one another under pressure, whereby the first and second drive means are adapted together to supply sufficient rotational energy to overcome the effects of resistive torque between the workpieces on initial contact between the workpieces; and thereafter continuing actuation of the first drive means to maintain relative rotation between the workpieces.
    Type: Grant
    Filed: December 30, 1986
    Date of Patent: April 5, 1988
    Assignee: Thomson Welding & Inspection Ltd.
    Inventors: Allan R. Thomson, Thomas V. Heath
  • Patent number: 4735473
    Abstract: In a device for optical-cable transport and combination of light images, the ends of an optical cable forming part of the device are coupled with lenses which are in turn associated with an optical system for dispersing radiation as a function of the wavelength in order to suppress any raster effect. This optical system is constituted at one end of the optical cable by a reflecting holographic mirror, the chromatic aberrations of which form the dispersion. At the other end of the cable, the optical system consists of a partially transparent holographic mirror for reflecting a first image to be transported and re-forming this image by suppressing the aberrations and combining said first image with a second image. The first image can be a synthetic image displayed on a CRT indicator and the second image can be the surrounding landscape in an application such as a helmet sight visor.
    Type: Grant
    Filed: May 5, 1986
    Date of Patent: April 5, 1988
    Assignee: Thomson-CSF
    Inventors: Jean B. Migozzi, Francois Grasdepot
  • Patent number: 4736161
    Abstract: A high frequency antenna is provided for an apparatus measuring nuclear magnetic resonance, of the type whose radiating means comprise conductors forming high frequency resonators with a metal casing. They are frequency tuned by adjustment capacitors situated at their ends. For simplifying the frequency tuning of two paired resonators through which flow currents in phase opposition, it is proposed to join together galvanically two ends of these two resonators by a high frequency line section whose length is substantially equal to half the wave length of the energization wave to be emitted. The frequency matching of the antenna may be made by adjusting simultaneously all the adjustment capacitors by means of a common control knob. Coupling of the energization energy is provided magnetically in the middle of this high frequency line section.
    Type: Grant
    Filed: June 4, 1986
    Date of Patent: April 5, 1988
    Assignee: Thomson-CGR
    Inventors: Claude Prevot, Robert Encellaz, Rene Chesneau
  • Patent number: 4736456
    Abstract: An automatic alignment system for the tuner of a television receiver with a controlled high-frequency preamplifier stage and an intermediate-frequency amplifier that has a reference circuit with a resonance frequency that can be switched to the arithmetic mean between the video-carrier intermediate frequency and the audio-carrier intermediate frequency during automatic alignment. The maximum control voltage is employed as a criterion for optimum alignment and an auxiliary oscillator is switched on during automatic alignment and generates through a mixing stage an auxiliary frequency that corresponds to the arithmetic mean of the video-carrier frequency and the audio-carrier frequency from the tuner-oscillator frequency.
    Type: Grant
    Filed: December 2, 1986
    Date of Patent: April 5, 1988
    Assignee: Deutsche Thomson-Brandt GmbH
    Inventor: Gerhard Maier
  • Patent number: 4734816
    Abstract: The invention concerns demagnetization devices used in particular for demagnetizing vessels or submarines in fixed stations, wherein one embodiment comprises: three sets of conductors for demagnetizing a vessel according to three directions; a direct current generator; an array of capacitors, a bridge switching device, an inductance coil; a switch allowing to select one of the three assemblies of conductors; a servo device for controlling the charge voltage of the array of capacitors; magnetometers; and a screen and keyboard allowing especially to supply a microprocessor with a reference value fixing the value of the desired residual magnetization; the demagnetization consisting of sending into each set of conductors a sequence of discharges, of smaller and smaller intensity and servo-controlled to the value of the remaining magnetization, in order to cause the magnetization to converge towards the desired value.
    Type: Grant
    Filed: September 19, 1986
    Date of Patent: March 29, 1988
    Assignee: Thomson-CSF
    Inventors: Germain Guillemin, Jean J. Periou
  • Patent number: 4734228
    Abstract: According to the invention, the dipolar orientation of an object made of material adapted to present piezoelectric properties is obtained by exposing at least one of the faces of the object to a jet of charged microparticles in order to create therein a sufficient electrical field to obtain the said orientation, and in a variant of the invention, a direct polarization is carried out by displacing a film in front of at least one generator of charged microparticles, this invention applying in particular to the production of film in a piezoelectric polymer or copolymer.
    Type: Grant
    Filed: June 13, 1986
    Date of Patent: March 29, 1988
    Assignee: Thomson-CSF
    Inventors: Francois Micheron, Jean P. Le Pesant
  • Patent number: 4734595
    Abstract: The present invention relates to a method for controlling a Darlington type circuit comprising a main transistor and an auxiliary transistor forming part of an integrated circuit, this control method allowing to reduce consumption, and with this purpose, the control transistor of the Darlington type circuit is connected, not as in classical schemas to the power supply voltage V.sub.CC but to an auxiliary voltage V..sub.AUX which, in the case if the drawing is higher than V.sub.CC be a quantity of about V.sub.BE1 +V.sub.BE2 -V.sub.CE1, V.sub.BE1 and V.sub.BE2 being the base-emitter voltages of the main transistor and of the auxiliary transistor and V.sub.CE1 being the collector-emitter voltage of the main transistor and preferably this auxiliary voltage is obtained from the power supply V.sub.CC by a continuous-continuous converter forming part of the same integrated circuit as the Darlington type circuit.
    Type: Grant
    Filed: September 17, 1986
    Date of Patent: March 29, 1988
    Assignee: Thomson-CSF
    Inventors: Geard Le Roux, Marius Reffray