Abstract: In a method of construction of an electrooptical display screen and especially a liquid-crystal screen, a control point of an image element is provided with a coupling element of ferroelectric material between an electrode and a control lead.

Abstract: The device of the invention comprises mainly a liquid crystal screen illuminated by a light source. An electrically controlled modulating device is placed between the source and the screen. Depending on the desired illuminating intensity, the electrical signal will be adapted to the modulating device. The modulating device may comprise essentially a liquid crystal cell.

Abstract: In a device for switching a light beam, the conditions of propagation of the beam are modified locally under electric control by interposing on the beam path a fluid which modifies the conditions of refraction of the medium traversed by the beam.

Abstract: The present invention concerns a device where the commutation of a luminous beam is ensured by the electrically controlled presence or absence, on the path of the beam, of a fluid causing said beam to be transmitted or reflected. The invention provides for improved decoupling between the output channels of the device, due to the presence of a surface provoking a total internal reflection that allows one to eliminate interference reflections.

Abstract: Optical modulator of a light beam comprising cells employing the displacement of an absorbent liquid and arranged in series on the path of the beam with a liquid displacement cell permitting a reflection of the beam.

Abstract: The invention relates to controlling a matrix access display device comprising a layer of material reacting to a combined thermal and electric effect. According to the invention, the DC video control voltage is transformed into an AC voltage by switching the potentials of the electrodes applying the electric control field.

Abstract: A memory display device using a chiral C or H smectic liquid crystal, comprising a liquid crystal cell in which optically discernible textures are induced by means of DC electric fields of appropriate signs, these textures being maintained under the effect of AC electric fields.

Abstract: The invention relates to a process for the production of a substrate for an electrically controlled device such as a display screen, said substrate integrating non-linear elements and control elements of the elementary display points. The invention relates to the production of a substrate, in its active part, has non-linear elements associated with each image element and produced from amorphous silicon and, in its peripheral part, polycrystalline silicon controlled elements. Initially the substrate has amorphous silicon layers, the peripheral crystallization being obtained by annealing in a temperature gradient furnace.

Abstract: A screen of a visual display device combining a thermal effect and an electrical effect for controlling an electrooptical material is obtained by replacing the glass plate of the screen facing the heating strips contributing to the thermal effect by a plate with better thermal insulation characteristics than glass, in order to reduce the control power.

Abstract: Smectic liquid crystal display screens for displaying a color image. The object of the invention is to obtain a color image from filtering layers deposited on the electrodes of a matrix display screen, the configuration of the electrodes supporting these layers being such that it avoids phenomena of interlineation of the colors.

Abstract: The invention relates to devices by means of which it is possible to cause fluid globules to circulate within a capillary space by means of pairs of electrodes establishing capture sites. The invention provides a device in which the electrodes of two successive pairs have in common at least one indentation comprising a convex part and a concave part. The invention is applicable, in particular, to the visual display and storage of electrical data by means of movable indices in the form of globules.

Abstract: The invention relates to a display using a varistor as the switching element for controlling the orientation of molecules forming a liquid crystal layer. It relates to providing the connections to the elementary cells on an insulating substrate and to forming on said connections varistor contact pieces ensuring a threshold control of the said cells.

Abstract: The invention relates to display devices with a mixed thermal and electrical effect. The invention relates to a special addressing mode making it possible to display a writing line, while limiting the control voltages to be applied from the outside to the display screen.

Abstract: The invention relates to a screen with matrix access which makes use of a varistor as a switching element to control the orientation of the molecules forming a liquid crystal layer. The invention has as its object the elimination of the passive surfaces of the varistor substrate and their replacement by an insulating material having a low dielectric constant.

Abstract: An electrically controlled visualization device comprising an electrochromatic material placed between a first electrode and a second electrode, said electrodes being supported respectively by two plates at least one of which is transparent, and said electrodes being connected to a voltage source adapted to produce a displacement of ions by diffusion which modifies the aspect of the said material, wherein an electric heating current passes through one of said electrodes, the duration of the application of said voltage being selected in such as a manner that said displacement is dependent on said current.

Abstract: The present invention relates to cells using a smectic phase liquid crystal film and provides in the same cell two addressing modes: optical addressing by means of a laser beam and matrix addressing by means of heating electrodes.

Abstract: A display device is provided using a liquid crystal layer associated with a photoconducting plate, in which the voltage applied to the valve is an AC voltage chosen so as to transfer to the liquid crystal a maximum signal, and that applies more especially to radioscopy and to the projection of coherent (laser reading) or incoherent images.

Abstract: An image contained in an incident signal is displayed on a screen forming part of a matrix-access display device. The device is primarily applicable to high-definition or small-area screens designed for operation in the transmission mode, and is controlled by an optical system. Optical addressing of a line array and a column array of electrodes is performed by means of light beams which serve to illuminate photodetectors.

Abstract: The invention relates to matrix access display devices using a mixed thermal and electric effect and provides a display device with mixed thermal-electric drive using a smectic liquid crystal deprived of a nematic phase by addition of appropriate dopes.

Abstract: The invention relates to a process for the production of a substrate for an electrically controlled device such as a display screen, said substrate integrating non-linear elements and control elements of the elementary display points. The invention relates to the production of a substrate, in its active part, has non-linear elements associated with each image element and produced from amorphous silicon and, in its peripheral part, polycrystalline silicon controlled elements. Initially the substrate has amorphous silicon layers, the peripheral crystallization being obtained by annealing in a temperature gradient furnace.