Abstract: Device for coherent addition of laser beams including several optical amplifiers in parallel pumped by a beam coming from a master laser. The beams emitted by these amplifiers are transmitted to a non-linear material and play the role of pump beams. The non-linear material also receives a signal beam derived from the master laser. The various beams of the amplifiers are therefore added in the non-linear material along the direction of the signal beam.
Type:
Grant
Filed:
November 30, 1990
Date of Patent:
June 9, 1992
Assignee:
Thomson-CSF
Inventors:
Jean-Marc Verdiell, Jean-Pierre Huignard, Henri Rajbenbach
Abstract: A device for correcting the faults of a sequence of images analyzed by an integrating matrix infrared sensor has a first part that determines a correction signal that is variable as a function of the temperature of the background of the images, equal to the product of a value representing the mean luminance of an image preceding the image undergoing correction, and a signal representing approximately the sensitivity of each cell of the sensor, constituted by the values of a video signal corresponding to an image analyzed in the course of a pre-calibration period; and a second part to determine a second correction signal, in storing the values of the first corrected video signal during a calibration period. An application of this device could be for the infrared cameras used in weapons systems.
Type:
Grant
Filed:
September 21, 1990
Date of Patent:
June 2, 1992
Assignee:
Thomson-CSF
Inventors:
Jean-Francois Le Bars, Jean-Marie Deler, Laurent Baron
Abstract: Disclosed is an optoelectronic device on a semi-insulator substrate, of the type comprising, stacked on one another, at least:one substrate made of semi-insulator material,one lower confinement layer with a first type of conductivity,at least one active layer in strip form, andan upper confinement layer with a second type of conductivity. In this device, the lower confinement layer covers one side of the semi-insulator substrate in passing beneath the active layer and coming to a stop substantially vertically to this active layer and the upper confinement layer covers the other side of the semi-insulator substrate in passing over the active layer and coming to a stop substantially vertically to this active layer. The disclosure can be applied notably to the fabrication of lasers.
Type:
Grant
Filed:
May 30, 1990
Date of Patent:
May 19, 1992
Assignee:
Thomson-CSF
Inventors:
Robert Blondeau, Daniel Rondt, Genevieve Glastre, Michel Krakowski
Abstract: A microwave generator that uses an electron beam and the phenomenon of the oscillating virtual cathode, but makes it possible to obtain energy with improved spectral quality and conversion efficiency as compared with standard vircator generators. This is achieved by the separate use of the electrons coming from the virtual cathode (80), that is, transmitted electrons (80) or reflected electrons (81) to convert their kinetic energy into microwave energy (4).
Abstract: Observers in the theater of operations use remote units to encode and transmit messages characterizing multiple events observed in theater of operations. The messages are composed from a predefined set of symbolic ideograms, representing and describing actions or objects likely to occur in the theater of operations. A central control center receives the multiple incoming transmissions. The messages are decoded and processed to produce a holistic accumulation of the various observations. According to one embodiment, the accumulation might graphically recompose theater activity according to correlated data received from the observers.
Abstract: A device comprising an inhomogeneous solid electrolyte of doped materials which are exclusive conductors for a predetermined chemical species. The electrolyte has a first region and a second surface region, the thickness of which is usually less than 400 .ANG.. In a first alternative embodiment, the second region is formed by increasing the doping percentage of the material constituting the first region. In a second alternative embodiment, the second region is formed by depositing a thin film of doped material chosen so as to ensure that the work function to be provided by the predetermined chemical species is of lower value than in the case of the doped material constituting the first region.
Type:
Grant
Filed:
February 13, 1991
Date of Patent:
April 21, 1992
Assignee:
Thomson-CSF
Inventors:
Michel Croset, Gonzalo Velasco, Philippe Schnell
Abstract: A device made with thin layers comprises at least two layers of materials having different electrical characteristics. At least one of the layers is superconductive. The superconductive layer comprises a rare earth (or yttrium) which is chosen so as to confer superconductive characteristics. The other layer has a constitution which differs from that of the superconductive layer, solely by the fact that the rare earth is different and confers different electrical properties.
Abstract: A bispectral pick-up and false color display system which comprises a bispectral camera for analyzing a picture in the visible range and a picture in the infrared range, and outputting two respective video signals, one for the visible range and one for the infrared range. A mixer then mixes these two video signals and derives, therefrom, three color control signals, each color control signal being a linear combination of the two video signals given by the bispectral camera. A manual setting device then sets or adjusts the coefficients of each of the combinations. A standard color television monitor then can display a picture as a function of the three color control signals. The disclosed device can be applied to target-sighting and target-tracking devices for land vehicles.
Abstract: A dimming device, with a brightness dimming ratio of 1 to 1000, for a fluorescent lamp used for the backlighting of a liquid crystal screen comprises a periodic signal generator for delivering rectangular pulses with an adjustable duty cycle. The pulses are synchronized with the image synchronizing signal of the liquid crystal screen. An alternating voltage generator provides power to the lamp only during the pulses. The decrease in tube efficiency for very short pulses allows the required dimming intensity to be achieved without image flickering.
Abstract: Disclosed is an electrically conductive composite polymer film formed from an organic matrix and conductive charges. The matrix is a polymer obtained from a filmogenic macromolecular latex and the conductive charges consist of a conductive polymer diffused in the matrix. The invention can be applied to microwave absorbent layers.
Abstract: Disclosed is a laser source with beam scanning, of the type comprising: a pump laser source emitting a pump beam with a determined wavelength; a pressurized gas cell receiving the pump beam and emitting, by Raman effect, an output beam with a wavelength called a Stokes wavelength; a control light source transmitting a control beam to the gas cell, this control beam having a wavelength that is substantially equal to the Stokes wavelength; wherein said light source includes means for the spatial and/or temperal modification of the injection of the control photons of the control beam into said cell constituted by a multiple-laser strip structure, forming a power slave laser and cooperating with means for modifying the radiation pattern of said multiple-laser strip structure, so as to prompt the emission of the output beam in a variable direction.
Type:
Grant
Filed:
October 3, 1990
Date of Patent:
April 14, 1992
Assignee:
Thomson-CSF
Inventors:
Jean-Paul Pocholle, Michel Papuchon, Jean-Luc Ayral, Claude Puech
Abstract: This amplifier stage comprises a microwave tube wherein an electron beam (3) is made to interact with a microwave having a frequency variable within a given useful range, the velocity of the electrons of the beam being determined by a cathode voltage (V.sub.k) applied to the tube and the microwave being propagated in said delay structure (4) that imposes a phase velocity close to the velocity of the electron beam on said microwave. The cathode voltage is a variable voltage, regulated as a function of said frequency, said voltage varying with the frequency to modify the velocity of the electrons of the beam in such a way that, for every frequency of said useful range of frequencies, the corresponding velocity of these electrons remains essentially, but not precisely, identical to the phase velocity of the microwave. Thus, the dispersivity in frequency of the delay structure is compensated for, and the output power delivered by the tube is thus kept essentially constant.
Abstract: A system for correcting the trajectory of a projectile so that it reaches a designated target. The system comprises an optical radar comprising a laser emitting in the infrared band that makes it possible, in association with a processing device, to follow the movements of the target and of the projectile at the same time. The pieces of information given by the processing device enable a computer to calculate corrections to be made to the trajectory of the projectile in a final stage so that it meets the target. By modifying the trajectory of a projectile, such as a self-propelled missile or a shell, launched towards a target, the projectile can be made to hit a moving target or pass by at a reasonable distance that is small enough for the explosion provoked by its charge to definitely destroy the target.
Type:
Grant
Filed:
October 13, 1989
Date of Patent:
April 7, 1992
Assignee:
Thomson - CSF
Inventors:
Georges Couderc, Jean-Louis Meyzonnette, Christian Pepin, Robert Pressiat
Abstract: A sonar that enables an already localized object to be found again uses a transmission antenna fitted out to transmit only the two .+-.first order secondary lobes. This antenna is supplied with a set of frequencies tiered so that each of these lobes determines a series of channels at transmission corresponding to these frequencies and filling two sub-sectors located to the right and to the left of the antenna. The reception is done by forming two wide channels, each of which covers one of the two transmission sub-sectors. The discrimination in bearing at reception is done by the discrimination of the frequencies. To cover a more extensive sector, including especially the central part located between two sub-sectors, the antenna can be made to rotate mechanically. This enables the construction of a simplified sonar which can be used in a consumable way.
Abstract: It describes a Microwave Landing System wherein.The means for surveillance of the transmissions from the various MLS stations are centralized in a single central station which then commands the various MLS stations. The connection between the central station and the MLS stations is assured by a network of optical fibers.
Abstract: The component-connecting device comprises several stacked and assembled wafers. Each wafer is made of an insulating material and includes conductive tracks that are rectilinear and parallel to one another. The tracks of two adjacent wafers are perpendicular. The tracks of the different wafers are made on a given side of the device. The device has zones for the connection of a component to that face, of the faces bearing the tracks, which is free, and these zones are electrically connected to tracks of other wafers. Finally, the tracks of the different wafers are extended as a connection zone with the exterior.
Abstract: In an acoustic wave reflector working in the sea, a sheet of air is set up between a reflecting plate and a perforated plate. This sheet of air forms a reflecting interface with the reflecting plate. A rubber bladder forms a container which, under the effect of the pressure of the water, feeds the sheet of air through the perforated plate. The thickness of this sheet of air is kept substantially constant up to the limit of submersion of the reflector. This makes it possible to increase the depth at which the acoustic reflectors are used.
Type:
Grant
Filed:
December 21, 1990
Date of Patent:
March 24, 1992
Assignee:
Thomson-CSF
Inventors:
Jean-Claude Giannotta, Robert Gagno, Eric Sernit
Abstract: A ring cavity laser device includes a slave laser placed in a ring cavity. The injection locking of a beam emitted by a master laser is achieved by a non-linear material in which interference occurs between the master laser beam and the beam circulating in the ring.
Abstract: The system comprises a central station assuring the generation of the microwave signals which must be transmitted by the different stations of an MLS. The signals thus generated in a centralized way are distributed to the different stations via an optical fiber network, the stations then assuring only the amplification and transmission of the signals.
Abstract: A method of making a multitrack head consisting in making a first network of grooves in a block of ferrite, filling the grooves with glass, planing down the surface, making a second network of grooves in a second block of ferrite, bonding these two blocks, trueing the base of the first block, depositing poles and making the winding wires go through.
Type:
Grant
Filed:
June 15, 1990
Date of Patent:
March 10, 1992
Assignee:
Thomson-CSF
Inventors:
Francois Maurice, Jean-Marc Coutellier, Maurice Penot, Claude Bussac, Paul-Louis Meunier