Abstract: Method for producing a display screen with a matrix of transistors provided with an optical mask. This method consists of depositing on a substrate (100) a layer of black polyimide (102) absorbing the visible light and followed by a layer of photosensitive resin, of insolating the resin through a mask masking the channels of the transistors to be embodied, of eliminating the zones insolated with the resin and the sub-adjacent zones of the polyimide, of depositing an ITO layer (106) on the unit, of eliminating the rest of the resin and the ITO surmounting said resin so as to form the drains/sources of the transistors, of successively depositing a layer of hydrogenated amorphous silicon (110), a layer of silicon nitride (112) and a layer of aluminium (114), then of photoengraving the stack of these layers so as to form the gate of the transistors, and finally to render passive the unit with a layer of silicon (116).

Abstract: According to the invention, the chip card issues a first certificate comprising its letter of credentials (Crc), an exponential (X), an optional message (M), these quantities being signed. The security module verifies the signature and in return issues a second certificate containing its letter of credentials (Crm), an exponential (Y), an optional message (M'), a cryptogram (C), these quantities being signed. A common secret key is constituted between the card and the security module by the exponentials and allows the card to interpret the cryptogram addressed to it and to act in accordance therewith.

Abstract: The station, in particular a terminal, comprises an oscillator (OS) having a feedback loop (1) and a station inductor element (L10) suitable for conferring a working frequency to the oscillator which varies relative to a rest frequency. The station also includes a station processor connected to the oscillator and capable of processing variations in the working frequency of the oscillator. The portable object, in particular a memory card, includes an electronic circuit which is switchable between an inactive state and an active state in which it sets up a resonant circuit tuned on a frequency which is distinct from the rest frequency while remaining suitable for being coupled inductively with the feedback loop (1) at the rest frequency. The portable object also includes an object processor capable of switching the electronic circuit as a function of the information to be transmitted to the station.

Abstract: Method for obtaining an organic polycrystalline material having in particular electro-optical properties, said material obtained and an electro-optical modulator comprising said material.This method includes a stage (1) for preparing a powder having a size grading of 500 to 800 nm of an organic compound having a delocalized system of electrons .pi. and presenting a non-centrosymmetrical crystalline structure, as well as intramolecular load transfer groupings, a stage (2) for drying the powder under vacuum, a stage (3) for pre-pressing the powder under vacuum, and a hot stage (5) for the uniaxial compression of the dried powder under vacuum.This method enables polycrystalline materials to be obtained, said materials comprising elongated monocrystalline grains orientated according to a given direction.

Abstract: An audio signal is multiplexed into a video picture signal by converting the audio signal into a sequence of digital code words from which subwords are extracted relative to a video signal line frequency. The number of bits in each subword is determined as a function of the amplitude dynamic range of the video signal, and each extracted digital subword is converted to provide analog samples with amplitudes proportional to quantizing of the corresponding digital subword. These analog samples are used to amplitude modulate an active portion of the video signal corresponding to a picture so as to provide a "composite" signal having the format of the video signal.

Abstract: The stereoscopic convergence is adjusted in stereoscopic imaging equipment to increase or decrease the stereoscopic convergence angle. Two imaging devices are disposed symmetrically relative to a median optical axis to generate video signals representing images of an observed scene. Depending on the required stereoscopic convergence angle, two image "read windows" are positioned symmetrically relative to the median optical axis, each being defined by a first pixel and a last pixel of a processed image line. The first and last pixels of a processed line are disposed between the first and last pixels of a raw (oversize) image line, with the result that the video signals generated by the stereoscopic imaging equipment represent righthand and lefthand processed images in corresponding relationship to the raw image read windows.

Abstract: An image system (SPI) provides an image file which is recorded in a memory (3). A segmentation and framing module (M1) isolates each of the characters in the image file within individual matrices. A module (M2) finds primitive shapes in each character matrix by initially finding strokes therein and then substracting the strokes from the matrix. A module (M3) then makes a description of primitive shapes in the form of at least one partially ordered list of primitive shapes, and a module (M4) compares said description with standard description expressed in the same manner in a data base (M5). Character recognition, per se, is performed by determining the distances between the description of a character to be identified and the standard descriptions.

Abstract: This invention relates to a process for surface treatment of a substrate carried by an electrode and immersed in a sealed engraving or deposition chamber equipped with plasma generating means, of the type involving the application to the electrodes, of a variable voltage, produced by a generator that is independent of the plasma generating means, wherein said process comprises the steps of:maintaining within said chamber a continuous plasma that is free of electromagnetic fields;supplying said electrode via a low impedance capacitor using a signal comprised of rectangular voltage pulses having:a variable pulse repetition rate to control the energy distribution function of the positive ionic charges bombarding the substrate,a variable mark-to-space ratio for each pulse to control the time distribution of the negative electron charges and the positive ionic charges bombarding the substrate, anda variable pulse amplitude to control the energy of the positive ionic charges bombarding the substrate.

Abstract: For processing data signals representative of pixels, each of the pictures s scanned, column per column in successive horizontal bands each having a height equal to an entire fraction of the height of the picture, whereby a representation of the picture as pixels distributed in rows and columns is obtained, each band having a common predetermined number of rows. The picture is fractionated into mutually adjacent blocks of pixels each having M pixels in each of N mutually adjacent columns, M and N being predetermined integers and M being a simple multiple of the number of pixels in one column of a band and N being a whole fraction of the number of colums per image.

Abstract: An end equipment comprises a subscriber line interface, a communication controller, a demultiplexing circuit, a multichannel receiving circuit, a multiplexer and a network line interface. The demultiplexing circuit receives data words at a rate n.D from the subscriber line, whereby n is an integer between 1 and a maximum value N. The data words are multiplexed in n independent channels selected among N multiplexed channels in a telecommunications network link at rate N.D. Each of N channels has a basic rate D. During a setting-in and synchronizing phase of a communication, synchronization frame bits are transmitted in the n selected channels. In a multichannel receiving circuit, the synchronization bits in n reception channels of the network link are detected sequentially, and a synchronization is carried out channel by channel.

Abstract: A binary multiplier circuit has a logic operator acting as an exclusive-OR gate generating a first intermediate signal which is an exclusive-OR of a first input and a carry-in input. An inverter generates a second intermediate signal. A second logic operator generates a first output bit which is a symmetrical exclusive-OR of a second input and both the first and second intermediate signals. A second output bit is a symmetrical trigger function of the first and second input, depending on the first and second intermediate signals, and is generated in a transmission gate. Since the carry-in signal passed via the first and second intermediate signals is applied directly to transistors of the transmission gate, carry propagation delay is reduced. A fixed operand is multiplied by a variable operand by storing a partial result of the multiplication using an accumulator and a shift register with the binary calculation circuit.

Abstract: An SOI MOS transistor comprises at least a highly doped lateral stripe (13, 14) of the same conductivity type as the substrate (3). This stripe extends along the edge of the substrate and of the source region (5) and is shorted with the source region through the conductive source layer (11).

Abstract: The station, in particular a terminal, comprises an oscillator (OS) having a feedback loop (1) and a station inductor element (L10) suitable for conferring a working frequency to the oscillator which varies relative to a rest frequency. The station also includes a station processor connected to the oscillator and capable of processing variations in the working frequency of the oscillator. The portable object, in particular a memory card, includes an electronic circuit which is switchable between an inactive state and an active state in which it sets up a resonant circuit tuned on a frequency which is distinct from the rest frequency while remaining suitable for being coupled inductively with the feedback loop (1) at the rest frequency. The portable object also includes an object processor capable of switching the electronic circuit as a function of the information to be transmitted to the station.

Abstract: Method for producing a display screen with a matrix of transistors provided with an optical mask. This method consists of depositing on a substrate (100) a layer of black polyimide (102) absorbing the visible light and followed by a layer of photosensitive resin, of insolating the resin through a mask masking the channels of the transistors to be embodied, of eliminating the zones insolated with the resin and the sub-adjacent zones of the polyimide, of depositing an ITO layer (106) on the unit, of eliminating the rest of the resin and the ITO surmounting said resin so as to form the drains/sources of the transistors, of successively depositing a layer of hydrogenated amorphous silicon (110), a layer of silicon nitride (112) and a layer of aluminium (114), then of photoengraving the stack of these layers so as to form the grid of the transistors, and finally to render passive the unit with a layer of silicon (116).

Abstract: A holographic method of the type implementing a conoscopic system including a birefrigent crystal inserted between two polarizers and a photosensitive element, wherein the method includes a step consisting in inserting one-dimensional optical means on the path of the light rays such that the conoscopic system only collects light that is parallel or quasi-parallel to a plane including the axis of the conoscopic system. The invention also provides apparatus for implementing the method.

Abstract: A holographic apparatus of the type comprising a conoscopic system including a birefringent crystal inserted between two polarizers, wherein the apparatus also includes an aperture angle limiter inserted on the path of the light rays and wherein one of the birefringent crystal and the aperture angle limiter is disposed off the optical axis of the apparatus.

Abstract: The process of the invention consists of subjecting a metal oxide coating (106, 108), located on a glass substrate (100), to the action of a gaseous plasma (109) containing 10 to 88% by volume of hydrogen, 2 to 30% by volume of a hydrocarbon and 10 to 50% of an inert vector gas, bringing about the formation of a polymer coating (110) on the parts of the substrate not provided with oxide, by dissocation of the gaseous mixture, and the partial chemical etching of the oxide (106, 108) by the formation of organometallic compounds.

Abstract: Process for the anisotropic etching of a III-V material and application to surface treatment for epitaxial growth.This process includes the step of etching a III-V material (2) by reactive ionic etching using a gaseous mixture containing by volume 20 to 30% of at least one gaseous hydrocarbon, 30 to 50% of at least one inert gas and 20 to 50% of hydrogen.Said etching can be performed locally with the aid of a Si.sub.3 N.sub.4 etching mask (4a).

Abstract: Joint closure modules and boxes for optical fiber cables, also known as splice organizers, the module having a supporting plate demarcating a shielded space of extension of the fiber transfer sections, said supporting plate including, firstly, a set of aligned and separate means for anchoring the external sheath, the peripheral reinforcements and the central strength element, respectively, of each cable and, secondly, at least one fiber coiling and connection cartridge with guided hinging, arranged so as to limit the transfer length and the course of shift of said sections for the transfer of the guided shift of said hinged cartridge.

Abstract: Photoreceptor for frequency-modulated optical signals. The photoreceptor consists of a semiconductor laser (10) fed clearly beyond the threshold (12). The optical signal (20) to be demodulated is injected into the laser. The voltage (V) taken at the terminals of the latter reflects the frequency difference between the frequency of the signal (F1, F2) and the actual frequency (Fo) of the laser.