Abstract: A method for transmitting a monochrome digital image from a digital image source connected to a monochrome scrZeen by a transmission interface including a plurality of transmission channels, the monochrome image including a plurality of image pixels, the monochrome screen including a plurality of display pixels, the method including dividing the image pixels into a plurality of pixel groups; successively transmitting the pixel groups from the digital image source to the monochrome screen via the transmission interface, the image pixels of each group of pixels being transmitted in parallel via the transmission channels; assigning each image pixel received by the monochrome screen to a corresponding display pixel in such a way as to reconstruct the digital image on the monochrome screen.

Abstract: The invention concerns an emissive display device including: a transfer substrate including electric connection elements; and a plurality of semiconductor chips (310) fastened to the substrate and connected to the electric connection elements of the substrate for the control thereof, each chip including: a plurality of LEDs (120r, 120g, 120b); a first terminal (Vdata) of connection to the substrate intended to receive, for each LED of the chip, an individual signal (Vdatar, Vdatag, Vdatab) for setting the LED, the individual signals for setting the different LEDs of the chip being temporally multiplexed on said first terminal (Vdata); and a control circuit capable of demultiplexing the signals received on said first terminal and of applying to each LED of the chip a bias signal which is a function of the individual LED setting signal received on said first terminal (Vdata).

Abstract: The invention concerns an emissive display device including: a transfer substrate including electric connection elements; and a plurality of semiconductor chips (310) fastened to the substrate and connected to the electric connection elements of the substrate for the control thereof, each chip including: a plurality of LEDs (120r, 120g, 120b); a first terminal (Vdata) of connection to the substrate intended to receive, for each LED of the chip, an individual signal (Vdatar, Vdatag, Vdatab) for setting the LED, the individual signals for setting the different LEDs of the chip being temporally multiplexed on said first terminal (Vdata); and a control circuit capable of demultiplexing the signals received on said first terminal and of applying to each LED of the chip a bias signal which is a function of the individual LED setting signal received on said first terminal (Vdata).

Abstract: A method for transmitting a monochrome digital image from a digital image source connected to a monochrome screen by a transmission interface including a plurality of transmission channels, the monochrome image including a plurality of image pixels, the monochrome screen including a plurality of display pixels, the method including dividing the image pixels into a plurality of pixel groups; successively transmitting the pixel groups from the digital image source to the monochrome screen via the transmission interface, the image pixels of each group of pixels being transmitted in parallel via the transmission channels; assigning each image pixel received by the monochrome screen to a corresponding display pixel in such a way as to reconstruct the digital image on the monochrome screen.

Abstract: An active matrix light-emitting diode display screens, and in particular those with organic diodes is discussed. The display screen includes an active matrix of pixels, each pixel including a light-emitting diode, a control MOS transistor for applying a variable voltage or current to the anode of the diode, a selection transistor for applying a variable analog voltage representing a relative level of luminance of the pixel in the image, to the gate of the transistor, during a write phase of this pixel, a storage capacitor for maintaining this voltage on the gate of the transistor outside the write phase. A mean luminance attenuation circuit including a switch for periodically connecting one of the electrodes of the diode, preferably the cathode, to one or other of two fixed potentials, and a switch control circuit for switching with a variable duty cycle according to the desired attenuation.

Abstract: A head-up display including a display screen including an array of display pixels arranged in rows and in columns, where the display screen is pivoted, around an axis perpendicular to the screen, by an inclination angle between 10 and 80 degrees, with respect to the position of the display screen for which a group of adjacent activated display pixels of a same row appears to an observer as being directed along the horizontal or vertical direction.

Abstract: A head-up display including a display screen including an array of display pixels arranged in rows and in columns, where the display screen is pivoted, around an axis perpendicular to the screen, by an inclination angle between 10 and 80 degrees, with respect to the position of the display screen for which a group of adjacent activated display pixels of a same row appears to an observer as being directed along the horizontal or vertical direction.

Abstract: An active matrix light-emitting diode display screens, and in particular those with organic diodes is discussed. The display screen includes an active matrix of pixels, each pixel including a light-emitting diode, a control MOS transistor for applying a variable voltage or current to the anode of the diode, a selection transistor for applying a variable analog voltage representing a relative level of luminance of the pixel in the image, to the gate of the transistor, during a write phase of this pixel, a storage capacitor for maintaining this voltage on the gate of the transistor outside the write phase. A mean luminance attenuation circuit including a switch for periodically connecting one of the electrodes of the diode, preferably the cathode, to one or other of two fixed potentials, and a switch control circuit for switching with a variable duty cycle according to the desired attenuation.

Abstract: A method to drive a display device with electron sources displaying grey scales divided into two families. The display device includes one or more rows and one or more columns. An intermediate potential lies between a first potential and a second potential. To display a grey level of the first family, the column voltage is pulse width modulated between the intermediate potential and the second potential right at the start of the row selection period. To display a grey level of the second family, the column voltage is pulse width modulated between the intermediate potential and the first potential from a determined instant of the row selection period.

Abstract: A method for driving a matrix viewing device displaying grey levels comprising a source of electrons at the crossing of line and column electrodes, consisting of applying a line selection voltage (Vls) on the line electrode and a voltage corresponding to the grey level on the column electrode. The grey levels are distributed into two families (F1), the first grouping the darkest grey levels, the second (F2) grouping the least dark grey levels. If the grey level belongs to the first family (F1), the voltage is pulse-width-modulated, if it belongs to the second family, the voltage is amplitude-modulated. The amplitude of the pulse-width-modulated voltage and the maximum amplitude of the amplitude-modulated voltage are reduced relatively to those required if the control was performed for all the grey levels by amplitude modulation or by pulse width modulation.

Abstract: A method of controlling display of a grey level at an associated image point on a matrix display screen. The screen includes lines and columns for which the intersections form an image point. Samples with non-linear proportional light intensity are used to display grey levels, instead of using samples with linear proportional light intensity, by selecting a coding that matches the response curve of the human eye because the eye is more sensitive to brightness differences at a low illumination level than at a high level. Its perception of brightness follows a non-linear law called the gamma correction law which in particular has been modelled by the International Lighting Commission (ILC).

Abstract: A method to drive a display device with electron sources displaying grey scales divided into two families. The display device includes one or more rows and one or more columns. An intermediate potential lies between a first potential and a second potential. To display a grey level of the first family, the column voltage is pulse width modulated between the intermediate potential and the second potential right at the start of the row selection period. To display a grey level of the second family, the column voltage is pulse width modulated between the intermediate potential and the first potential from a determined instant of the row selection period.

Abstract: Process and device for control of an electron source with matrix structure, regulated by the emitted charge. The invention is applicable to an electron source comprising addressing rows and columns which intersect to define emission areas, the electrons being supplied by the columns. According to this invention, the emission of electrons is triggered by increasing the potential of the columns to a value that will enable preferential emission of unaddressed rows. Then, throughout the emission duration, the potential of columns will be kept equal to this value, while simultaneously making measurements in the columns of the quantity of charges emitted by the pixels in the said columns. Secondly, when the quantity of charges measured on a column reaches a required charge quantity, the potential of this column is switched to a value that will block the emission of electrons. The invention is particularly applicable to flat field emission displays.

Abstract: Control method for a matrix display screen wherein a line selection voltage is applied to a line during a line selection time and simultaneously a voltage is applied to a column corresponding to a grey level to be displayed chosen from among 2q levels and numerically coded according to a non-linear law in accordance with the perception of the eye. The voltages to be applied to the columns are chosen in an increasing series of (2n+1) voltages distributed in pairs that display a range of grey levels.

Abstract: A method controls voltage of a matrix structure electron source. The method includes setting the emission of electrons by applying potentials on the selected line and column(s) at a value allowing this emission, maintaining these potentials at their value throughout the duration of the emission, carrying out a sampling and analog memorisation of the emission current of each pixel of the column(s) at the start of the emission time, and using another current supplied by a current generator that is proportional to the value of the measured emission current circulating the column(s); and measuring the quantity of charge delivered, during all or part of the remaining line time, by each current generator, and when this quantity reaches a required value, commuting the potential of the column associated to the current generator to a value that ensures the blocking of the emission of electrons of the pixel of this column.

Abstract: Process and device for control of an electron source with matrix structure, regulated by the emitted charge.

Abstract: The invention concerns a method for controlling the voltage of a matrix structure electron source, in which:

Abstract: The invention relates to a control process for a structure with field effect elements, the structure comprising a cathode (1) equipped with field effect elements, an anode (2), an extraction grid (7) and an additional grid (14). The process comprises at least one phase in which electrons are emitted to the anode by field effect elements, and at least one regeneration phase during which the electrons output from the elements are not transmitted to the anode. The regeneration phase is implemented by applying an electron blocking voltage (VB) to the additional grid (14) such that electrons drop back to the cathode. The invention is applicable to flat image display screens and any device comprising a field effect cathode (x-ray tube, etc.).

Abstract: The invention relates to a method for displaying different levels of grey on a matrix screen including pixels arranged along R rows and M columns of images having Q.sub.S levels of grey and obtained by addition to each pixel during the writing of image data line-by-line, during Sub-times (lines or frames, S being at least 2), of a succession of discrete luminance levels selected from among N such that any grey hue included between 0 and Q.sub.S-1 may be defined by the addition of S said luminance levels. The invention also relates to a system for implementing such method. Particular utility for the present invention is found in the area of displaying data on micropoint screens.

Abstract: A multiplexed matrix display screen and a process for controlling same are provided. The screen has n row electrodes (10) and m column electrodes (8), which cross one another, and n control circuits (26i) for successively controlling the n row electrodes, with n and m being integers greater than or equal to 2. At least one control circuit for a row electrode (Li), with i being an integer such that 1<i.ltoreq.n, is provided having means for applying to the row electrode (Li) a selection voltage during a first selection time and then a discharge potential during at least part of a second selection time of at least one other row electrode (Li+1), and for placing the row electrode Li under high impedance outside the first selection time and said part of the second selection time. Control circuits (24) for simultaneously applying to the m column electrodes during the first selection time potentials appropriate for displaying data on row Li are also provided.