Abstract: The read circuit can be applied to optomechanical scanning imaging devices. The circuit is designed for the reading of batteries of photodetectors comprising a specified number N of detection channels, each constituted by N.sub.d sensors positioned in the scanning direction, such that each point of an image is successively analyzed by N.sub.d sensors of a channel. The circuit includes a current summation scale, associated with each detection channel, formed by a specified number M of current summation circuits and coupled to the detection channel by means of a voltage-current conversion device. Application to the thermal imaging devices.

Abstract: A system for the control of light beams includes a beam splitter placed on the path of the beam to be controlled and deriving a measurement beam from this beam; a detection device receiving the measurement beam and measuring the shape of the wave front of the measurement beam; a wave-front shape correction device placed on the path of the beam to be controlled, activated by the detection device and correcting the shape of the wave front of the beam to be controlled. The detection device includes a light spatial modulator providing for the selective transmission of the portions of the measurement beam; a focusing device receiving the different portions of the measurement beam; a series of photodetectors placed along the focusing plane of the focusing device; a device for the identification of the photodetector or photodetectors, detecting a light wave and computing the shape of the wave front as a function of the photodetectors identified.

Abstract: A miniaturized VHV transformer/rectifier for surface mounting on a screen-printed ceramic substrate. The primary winding and secondary windings are wound on separate limbs of the magnetic circuit which are sufficiently far apart to obtain a considerable leakage self-inductance. The secondary winding is formed by a stack of pancake coils each including a respective winding and the associated diode bridge along with their respective connections. The primary is cemented to a ceramic interface plate which is metallized on its rim to make a transfer plate coinciding with the surface of the receiving substrate.

Abstract: This radiating slot array antenna is made out of a printed circuit sandwich structure with: a radiating plate in printed circuit form transparent to microwaves having, on its upper face, a metallization plane in which there are etched alignments of radiating slots; chutes made of a plastic material with a metallized inner wall, the chutes having their hollow part before the upper face of the radiating plate, being soldered by their edges to the metallization plane of the upper face of the radiating plate on and parallel to the alignments of radiating slots so as to overlap them, and reconstituting the three missing walls of waveguides whose fourth wall is constituted by the metallization plane etched with radiating slots of the upper face of the radiating plate; and an upper plate assembled on the back of the chutes to ensure the stiffness of the antenna. Its composition as a sandwich of printed circuits gives it high rigidity, great lightness and a low cost price.

Abstract: A clock circuit for the reading of sequential information elements includes a phase-locked loop for the control of the controlled oscillator. In the case of a reading system with n tracks, the phase computation circuit, the digital filter and the controlled oscillator each include as many memories (delay circuits R 1.1, . . . R 2.1, . . . R 3.1, . . . ) as there are samples of information elements (or information tracks) to be processed almost simultaneously. The invention finds particular application in the reading of high-density recording media.

Abstract: A method for dynamic generation of synthetic images employs Delaunay mesh generation. Only the terrain portions of which a significant variation in the detail level takes place are processed in real-time, this significant variation being determined by the angular error, from the observer's point of view, and relative to the various points of the terrain, which would be committed if these points were not processed, only the angular error greater than a certain threshold being taken into account.

Abstract: The disclosure relates to charge-coupled devices taking the form of shift registers and, more specifically, to those working in the MPP (Multi-Pinned Phase) mode, i.e. with high negative polarisation of the electrodes during the phases of waiting or of integration of integration of the photosensitive charges. These registers use a potential barrier created by a P type compensating implantation in a zone 16 located beneath a first electrode of each stage of the register. This barrier separates the stages from one another. To increase the charge storage capacity during the storage phase and the charge transfer capacity during the transfer, it is provided that the compensating implantation of the zone 16 will extend beneath only one part (and not the totality) of the first electrode of each stage of the register. Application to photosensitive image sensors, analog delay lines, charge-coupled analog memories, working in MPP mode during the waiting phases to limit losses of information due to the dark current.

Abstract: In a method to fabricate a printed circuit having a surface plated with a base metal layer, an improvement including depositing a first metallic resist on the base layer to delimit at least patterns of circuit elements to be etched in a layer having a first thickness, forming metallized holes in the plated surface after depositing the first metallic resist; and depositing a second metallic resist after forming the metallized holes to delimit at least patterns of circuit elements to be etched in a layer having a second thickness greater than said first thickness, whereby more accurate etching in the metal layer having the first thickness compared to etching in the metal layer having the second thickness is possible.

Abstract: The invention relates chiefly to double antennas for metric and decimetric waves, designed for vehicles. The antenna comprises a single-pole antenna for low frequencies surmounted by a dipole type antenna for high frequencies. The supply cable of the dipole antenna has an external conductor used to form the single-pole antenna above the ground plane. Beneath the ground plane, this external conductor is wound in turns to constitute the secondary winding of a transformer for the supply of the single-pole antenna. Application especially to ground vehicles.

Abstract: Coherent bursts of N wideband, low repetition frequency width-modulated pulses are transmitted, and they are received with pulse compression and then sampling. For each range gate and each speed hypothesis, a selection is made of the corresponding samples of N repetitions of a burst after compensation for the migration in distance. On each set of N samples, for a given speed hypothesis, a Fourier transform and a threshold-setting operation are performed. The distance and the unambiguous speed of the detected targets are then extracted.

Abstract: A semiconductor laser source, including a stack of semiconductor laser diodes each including at least one active region. The active region includes a series of semiconductor layers located between an ohmic contact layer and a substrate which also assumes the function of an ohmic contact layer. Pressure keeps the diodes in contact with one another by way of their ohmic contact layers. Each diode has dimensions, especially in their thickness, so that the transient heating in each diode is as small as possible and so that the average heating in the stackable diodes does not exceed a predetermined value.

Abstract: A magnetic head has two poles separated by a gap and at least one saturable element. The saturable element joins the poles and is outside the gap and parallel to the gap. The head may be in the form of a matrix device having a number of poles mounted over a similar number of pads in the substrate. The saturable element may link two poles of the head by means of a pole of another magnetic head.

Abstract: The disclosure relates to a glass substrate coated with a silver-based deposit, with a nitride-based barrier interposed between the glass-substrate and the silver-based deposit to prevent a yellow coloring of the glass prompted by the diffusion of silver in the glass. Application to silver panels.

Abstract: A detector with quantum structure comprising a small-gap semiconductor material inserted between two large-gap semiconductor materials, the structure comprising a coupling grating between the wave to be detected and the detector zone constituted by the small-gap material. Under these conditions, the detector zone may have a very small thickness (typically of the order of 1,000 .ANG.) and lead to a detectivity, limited by the dark current, that is high.

Abstract: A process for producing magnetoresistive transducers, using microlithographic techniques, where the transducers have magnetic metallic multilayers deposited by sputtering or by molecular beam epitaxy, and forming columns whose side walls will be covered with an insulation and whose tops will be free of this insulation, such that a current is able to flow in the magnetoresistive transducers perpendicular to the plane of the layers so as to exploit a phenomenon of perpendicular giant magnetoresistance. This process includes a step of producing, on one surface of a substrate, a stack including a first conductive layer in contact with a substrate and successive magnetic layers and non-magnetic metallic layers constituting a magnetic metallic multilayer in contact with the conductive layer.

Abstract: A process for reading binary information written on a carrier. The carrier has at least one track and the binary information is written onto the carrier at a frequency Fbit. The process includes the step of reading binary information at the sampling frequency F.sub.e to form a succession of successive read samples SAM(k) of the same track. SAM(k) is the read sample of order k, each read sample having a phase .phi.(k) lying between 0 and 2.pi.. The method further includes a step of interpolating to make it possible to calculate an interpolated sample I(k) with phase equal to .pi. which corresponds to read sample SAM(k) on the basis of the read sample and on the i+j read samples which bracket the original read sample SAM(k) such that:I(k)=a.sub.k-i SAM(k-i)+ . . . +a.sub.k SAM(k)+ . . . +a.sub.

Abstract: In a method and device for frequency-modulated continuous-wave radar detection with removal of ambiguity between the distance and the speed, the radar sends out at least alternately two parallel and discontinuous frequency modulation ramps that are slightly offset by a frequency variation (.DELTA.F), the frequency switching from one ramp to the other at the end of a given duration (Tf), the distance from a detected target being estimated as a function of the difference in phase (.DELTA..phi.) between a received signal (S.sub.1 (t)) corresponding to the first ramp and a received signal (S.sub.2 (t)) corresponding to the second ramp, the speed of the target being obtained from the estimated distance and the ambiguity straight line associated with the target. The disclosed method and device can be applied especially to radars for automobiles.

Abstract: Disclosed is a device for the reduction of noise in a radar receiver. The noise to be reduced being governed by a 1/F.sup.k relationship and the radar carrying out an encoding of the transmission in at least two frequencies, the device comprises at least the following means: firstly, means for routing the signals received to at least two channels so that, when a target is illuminated by a transmission at the first code frequency (F.sub.1), the corresponding received signal (S.sub.1) is sampled and routed to a first channel and then, when the target is illuminated by the second code frequency (F.sub.2), the corresponding received signal (S.sub.2) is sampled and routed to a second channel; and secondly, means for the linear combination of the signal (S.sub.1) present in the first channel and the signal (S.sub.2) present in the second channel, the linear combination synthesizing a filtering of the noise.

Abstract: In a multi-processor system, the semaphore device comprises a latch associated by software or hardware to a non-shareable resource. The output of the latch is connected to the bus for the re-reading of the semaphore by the processors. The output of the latch is also connected to an input of a multiplexer connected by its other input to the write bus of the semaphore. The control field output of the latch is connected to an AND gate receiving, at its other input, the control bit of the bus and conditioning, by its output, the writing of the latch. The task seeking to appropriate the semaphore tries to write its unique identifier in the latch with the control field at <<1>>. It then re-reads the semaphore register. Equality between the value re-read and the value written means that the task has succeeded in appropriating the resource. The source is released by the writing of the control field at <<0>>.

Abstract: The disclosed jacket comprises a layer that is discreet with respect to the visible and infrared frequencies, having a specified thickness, with a specified dielectric permittivity and emissivity close to 1 for the infrared frequency bands considered; a resistive layer, with an electrical resistivity and thickness that are determined so that the inverse of their product gives a specified resistance; a layer of dielectric material with a specified thickness and a specified dielectric permittivity; and a conductive layer with electrical conductivity determined so that it is considered as a reflective plane for the radar frequencies considered.