Abstract: The invention concerns a display screen with active matrix comprising first and second transparent substrates enclosing a crystal liquid material, at least one counter electrode, pixel electrodes in lines and in columns, data lines, perpendicular selection lines, control devices for connecting the lines to the pixel electrodes, the pixel electrodes being controlled such that the electrodes connected to a common selection line have the same polarity while, for two adjacent selection lines the polarity is reversed, the pixel electrodes being located in a first plane while the other elements are located in a second plane distanced from the first plane, and a transparent mass plane being located between the two planes. Moreover, the mass plane has a structure such that at least the part found between two pixel electrodes of same polarity is recessed. The invention is applicable to LCD.

Abstract: The present invention relates to a method for addressing a flat screen composed of lines and columns, with pixels located at their intersections, characterized in that, at the start of each sampling of the video signal to be displayed on the screen, a voltage (Vr) higher than the working voltage range (V) is applied to the selected pixel for a time tr, then the working voltage is sampled for a time ts.

Abstract: A compensation process for a circuit comprising at least one first conductor at a specified potential, at least one second conductor generating disturbances by capacitive coupling to the conductor and at least one disturbance compensation bus capacitively coupled to the first conductor by a first capacitor includes the steps of measuring the voltage and the current on the compensation bus, calculating the voltage on the first disturbed conductor, and determining the set-point voltage to be applied to the compensation bus in order to compensate for the disturbance.

Abstract: A shift register having several cascaded stages, each stage containing an output at a first node connected to a next stage, a first input connected to an output of a preceding stage, a second input connected to an output of the next stage and a first terminal connected to a first clock signal and a second terminal connected to a second clock signal, the stage containing a first semiconductor device switching the output of the stage between high and low values of the first clock signal, the first semiconductor device being controlled by the potential of a second node, itself connected to the output of the preceding stage across a second semiconductor device controlled by the output of the preceding stage; to a negative potential across a third semiconductor device controlled by the output of the next stage; and to the second terminal connected to the second clock signal across a first capacitance, wherein a second capacitance is mounted between the second node and the output of the next stage.

Abstract: The subject of the present invention is a shift register for an LCD, the stages of which use the Boostrap [sic] effect and can contain just three M.I.S. transistors, as well as enhancements to this circuit with four or seven MIS transistors.The advantages are the low number of components used, the increase in the lifetime of the shift register and the possibility of working with control signals having an amplitude of 5 or 10 v below that of the output signals.

Abstract: The present invention relates to an optimized method of addressing liquid-crystal screens. In accordance with the invention, the matrix addressing method, periodically scanning each line with a signal of voltage V.sub.A (t) as a function of time, is characterized in that each period of this signal consists of a plateau up to T.sub.F then a curve which may be a straight-line portion of slope .alpha. between T.sub.F and T.sub.F'. Application to liquid-crystal screens.

Abstract: The present invention can be used to make integrated circuits on the same substrate as the active matrix owing to the possibility that it offers of connecting transistor gates to sources or drains of the same or other transistors, and thus be used in a "integrated drivers" technology. It is also possible to make different types of transistors and capacitances using this method, without adding any additional mask levels.

Abstract: A device for attenuating stray capacitances in a liquid crystal and active matrix screen. The screen includes a substrate plate on one face of which there are deposited electrodes and thin film components controlling the electrodes. It also includes a back plate having one or more back-plate electrodes and covering the face of the substrate plate. A liquid crystal is contained between the electrode of the substrate plate and the back-plate electrodes. A ground plane forms an equipotential over the whole surface of the screen between the substrate plate and the thin films of the control components. The ground plane along with a film of insulating material forms a storage capacitance.

Abstract: A device for encapsulating and passivating integrated control circuits of flat screens. A sealing bead is placed on a substrate plate in order to encapsulate and passivate an integrated control circuit mounted on the plate. In one embodiment, the sealing bead is placed directly on top of the control circuit. In a second embodiment, the sealing bead is placed on both sides of the circuit so as to form a chamber which is separate from that which contains the active matrix. In a third embodiment, an opaque material is also placed on top of the circuit which acts as a spacer and may also act as a "black matrix".

Abstract: A device for improving a contrast of a liquid crystal screen by using an opaque mask. The display screen includes a first plate, on one face of which are deposited elements with controlled transparence or reflectance and thin film components controlling these elements, and a back plate covering a face of the first plate including the elements with controlled transparence or reflectance and the thin film components. The elements are separated by opaque bands into lines and columns forming a grid. The opaque bands are deposited at least partially on the plate including the elements and the thin film components.

Abstract: This invention concerns active matrix flat displays in which the pixels (10) are placed at the intersections between two mutually-perpendicular sets of conductors known as lines (L1 to LN) and columns (C1 to CM). In the invention, each pixel consists of two capacitors (CON1, CON'1) connected in series and consisting of electro-optical components, this circuit being connected between two control transistors (T1, T'1), these two transistors being connected to a common line (L1) and two different columns (C1, C'1) respectively.

Abstract: Disclosed is a color matrix screen with colored filters in a triad or delta layout. In this layout, the pixels are formed by two adjacent sub-pixels that are aligned along the lines and columns of the matrix, the colored filters of the lines n (n may be odd or even) being arranged according to the sequence A,A, B,B, C,C and the colored filters of the lines n+1 being arranged according to the sequence C,C, A,A, B,B where A,B,C is any combination of red, green, blue with the offset of a sub-pixel at each end of the line, and wherein each column is constituted by two parallel column elements connected to each other at each end, two adjacent sub-pixels of a line with colored filters of a same color being each connected to a different column element Application to liquid crystal screens.