Abstract: Disclosed is a process for the synthesizing of polysilsesquioxane, including a first step for the hydrolysis, in the presence of ether, of trichlorosilane with the general formula RSiCl.sub.3 where R represents an organic radical, notably an alkyl, an aryl, a vinyl or an allyl, said process further including the following steps;2nd step: the dissolving of the solid product obtained at the end of the first step in an anhydrous ketonic solvent and the addition of a base, the reaction taking place under heat, a solid product being obtained after evaporation and drying;3rd step: the dissolving of the solid product obtained at the end of the second step in an anyhydrous ketone, the addition of a chain-terminating agent, the reaction taking place under heat and the solution obtained being filtered, evaporated and dried to give the desired polysilsesquioxane,wherein the second step is repeated several times.

Abstract: This device has, on one and the same component: an image zone having a first array of at least one line of cells integrating an electrical charge than can then be transferred from point to point in the array, along the line, up to an end of this line; a memory zone having a second array with a same number of lines of cells and a transfer zone. The line of the second array is a looped line sequenced like the corresponding line of the first array, and at the same rate, and the transfer zone includes charge divider means receiving, at input, said charge transferred from point to point in the first array along the line and dividing said charge into two sub-charges with a pre-determined relative ratio; means to neutralize the first of these sub-charges; and means to add the second of these sub-charges to the charge received at output of the looped line and to reinject the resultant total charge into the input of the looped line so as to make it recirculate therein.

Abstract: The invention is a series of amorphous copolymers which, used in association with a small molecule, provide photorefractive materials that can be used in optical signal processing. These copolymers contain an active non-linear optical group and a group which contributes to their photoconductivity. ##STR1## where: X is H, CH.sub.3, Cl or FY is H, CH.sub.3, Cl or F2.ltoreq.n.ltoreq.42.ltoreq.m.ltoreq.4The electron-donor group D being:--O--, --S--, ##STR2## or --COO-- The electron-acceptor group A.sub.e being: --CN, --NO.sub.

Abstract: Disclosed is a method and a device for the on-line testing of an antenna formed by a plurality of radiating sources. In an application for example to a secondary radar antenna, it is proposed to memorize the patterns (.SIGMA., .DELTA. and .OMEGA.) of the antenna when all the radiating sources work properly and, when each of the source is malfunctioning in turn, to meaasure the radiation patterns of the antenna during its operation in IFF mode and then to compute the coefficients of correlation of these patterns with all the corresponding memorized radiation patterns. The value of the coefficients obtained enables the precise determining and localizing of the malfunction. It is furthermore proposed to use a ground beacon responding to all the interrogations on several antenna rotations.

Abstract: A process for estimating the distance between a stationary object and a vehicle by providing the processing of images from the speed of enlargement of an image of an object seen from a vehicle. Images of the object are analyzed by an image speed sensor mounted on a vehicle and these images are centered relative to the speed vector of the vehicle. The luminance values of the pixels of the images successively analyzed by the sensor and the luminance value of pixels of a series of predicted images are integrated in a plurality of image memories corresponding respectively to a plurality of predetermined values for the distance. The luminance value of each pixel of a predicted image is determined as a function of the integrated luminance value for a pixel being considered, as a function of the speed of the vehicle, as a function of the position of the pixel in the predicted image and as a function of the distance value corresponding to the particular memory being considered.

Abstract: The aim of the method is to prevent parasitic metallizations on the lateral walls of a raised pattern, which is used to self-align the electrode metallizations in a transistor. To this effect, a pair of semiconductor materials is introduced into the vertical pattern. These semiconductor materials react differently with respect to a pair of etching methods, so that a layer of one semiconductor material is etched to a greater extent than the other layer. The overhanging feature thus created interrupts the parasitic metallizations, if any, between the electrodes. The disclosed method can be applied to vertical structures.

Abstract: The field of the invention is that of frequency doublers. More precisely, the present invention concerns a low noise frequency doubler, which in particular can operate at frequencies of the order of several GHz, or even of several tens of GhZ. According to the invention, the frequency doubler, operating in particular in the microwave range, is of the type including means of phase shifting to obtain two signals with a phase difference of 180.degree. from an input signal of frequency F and means for amplifying each of these two signals, the output signal of frequency 2F formed by adding the said amplified signals, the said means of amplification cooperating with means for varying the gain of the said means of amplification to make the gain of the said means of amplification practically proportional to the amplitude of the said amplified signals.

Abstract: In the matrix magnetic head of the invention, the ferrite pads (4 to 8) of the magnetic circuits of the micro-heads are arranged quincunxially, and each pad is joined to the four neighboring pads by poles (9 to 12). There are therefore twice as many micro-heads as there are magnetic pads.

Abstract: Disclosed is a method for the processing of a signal received directly or indirectly from a transmitter, sending out pulses that are digitally encoded according to a transmission code of N instants; said processing comprising notably an operation of filtering that is matched with the transmitted signal and an operation of detection by the comparison of the post-filtering level of the signal with a so-called detection threshold; wherein the signal received is subjected to two processing operations A and B, the processing operation A comprising a self-correlation and the processing operation B comprising an intercorrelation with a mismatched code having a length at least equal to 3N, the function of intercorrelation of this mismatched code with the transmission code giving a major central lobe and at least N side lobes that are zero on either side of this major lobe; and wherein it is decided that there is a detection relating to one of the instants of the correlation or of the intercorrelation only if the leve

Abstract: A quantum well optical device including a layer of semiconducting material of large forbidden band width and, situated in this layer, at least one quantum well, such as a quantum line or quantum hole, of a material having a narrower forbidden band than that of the layer. This quantum well has two permitted electron levels. Means exist of assuring the electron population of the first permitted energy level.

Abstract: The disclosed display device for simulators has an off-axis collimated display system: a spherical screen and a spherical mirror that are fixed to a helmet worn by the user. This device gives a wide horizontal field and a relatively low attenuation of the external view.

Abstract: For the observation of an elongated object or an elongated zone (12) of an object with a lens (20, 20', 54), in the vicinity of this object or zone (12), a cylindrical lens (23) is used whose axis (Ox) extends along the largest dimension of the object or the zone. In this way, the observation is performed with a large resolution on an extended field.

Abstract: The present invention concerns an arrangement for reading an optically readable light reflective carrier on which data is stored in form of diffractive elements which are deviations from a reference surface. The data elements each have a plurality of adjacent tracks located on the carrier with data elements being positioned on adjacent tracks. The system utilizes an illumination system for projecting a concentrated light spot onto the carrier along a track wherein the diffraction is such that the light emerging from the diffractive track has a spatial distribution representing an amount of track misregistration between the spot and the axis of the track.

Abstract: Disclosed is an image projector in which a spatial modulation of light is carried out on the two orthogonal components of polarization of light in order to increase the luminous efficiency of the projector. The image projector of the invention includes a light source, a projection screen, a splitter of polarizations splitting the light into two polarized beams having complementary polarizations, two mirrors reflecting the two polarized beams, firstly so as to give them opposite directions and superimpose them on one and the same axis on which a spatial light modulator is positioned and, secondly, to make them pass again through the polarization splitter by which they are superimposed on one and the same axis with one and the same direction and oriented towards the projection screen and/or the light source as a function of their modulation by the spatial modulator.

Abstract: The invention concerns an inductance device formed on the basis of an asymmetrical line. This inductance device includes a plane conductor, preferably cylindrical, a linear conductor extending along and close to the plane conductor and having one end short-circuited with the plane conductor. Positioning devices make it possible to keep the linear conductor in a determined position in relation to the plane conductor. The inductance device is particularly used for the manufacture of power inductances for short waves.

Abstract: The disclosure concerns neural networks designed specially for the classification of objects represented by vectors X. If the vectors X include several parameters and if the objects have to be classified in a large number N of classes, the end result is a very large number of interconnections which become difficult to set up physically, are slow in their operation and require lengthy learning phases. The disclosed neural classification system has the particular feature of being constituted on the basis of P neural networks each individually carrying out the classification of objects in only two classes or, at any rate, in a small number of classes only. These networks give probabilities P.sub.i,j of membership in a class C.sub.i among two classes C.sub.i and C.sub.j. The outputs of these networks are connected to a signal processing module which, through simple functions (implementing linear combinations of the outputs and non-linear standardization functions) establishes, on N outputs, results P.sub.

Abstract: A semiconducting component with a Schottky junction with stacked electrodes has a lower electrode forming an emitter or source, a central electrode forming a base or grid and an upper electrode forming either a collector or a drain. Semiconductor material is between the upper electrode and the lower electrode. The central control electrode is in the form of several adjacent conducting fingers. An insulating material is in the region directly below the fingers between the control electrode and the lower electrode, thereby reducing parasitic capacitance between the control electrode and the lower electrode.

Abstract: The present invention concerns an arrangement for reading an optically readable light reflective carrier on which data is stored in the form of diffractive elements which are deviations from a reference surface. The data elements each have a plurality of adjacent tracks located on the carrier with data elements being positioned on adjacent tracks. The system utilizes an illumination device for projecting a concentrated light spot onto the carrier in order to obtain diffraction of light along the entire length of each of the data elements with an optical arrangement collecting light reflected from a carrier in such a way that the light energy which is received when a projected light spot impinges on the reference surface is greater than the light energy received when the projected light spot impinges on a data element.

Abstract: Disclosed is a portable device for the measurement of the dose rate and of the doses of photon radiation such as gamma rays, UV rays or X-rays, or charged particles, to which a bearer is exposed. This device has a detector of radiation or particles, a system for computing the cumulative dose and a memory to store data relating to the bearer and to the cumulative doses. The device has a credit card type of format, and is preferably like a badge with a photograph. It has a clock-calender for the storage, in the memory, of a piece of information on dates at the same time as the pieces of information on doses and/or dose rates.

Abstract: The invention relates to a solid laser with an emission wavelength lying between 0.5 and 0.65 .mu.m. A chromium-doped Mg.sub.2 SiO.sub.4 (forsterite) laser rod is pumped by a laser diode emitting between 0.75 and 0.8 .mu.m, this laser diode having an active layer which is Ga.sub.1-x Al.sub.x As based, with x lying between 0.1 and 0.18. The laser device finds particular application in the isotopic separation of uranium.