Abstract: The present invention relates to a device for driving a plasma display panel having a plurality of cells arranged in rows and columns, said device comprising row address means for selectively addressing the display cell rows and creating, where required, in cooperation with means for selectively applying data voltages to the display columns, an electrical discharge inside the cell disposed at the intersection of the row and column selected during an address phase, and sustain means (I3, I4, I5, I6) for sustaining the electrical discharges inside said cell during a sustain phase immediately following the address phase. According to the invention, the row address means and/or the sustain means are capable of allowing a bi-directional current to flow in the display cells during the address and/or sustain phases. The capacitive and light-emission currents appearing during these phases can thus flow freely and do not create electromagnetic interference.

Abstract: The invention relates to a backlight device with light emissive diodes not requiring the supply of a large current. According to the invention, each light emissive diode of the backlight device is combined with a voltage converter capable of storing energy during part of the operating cycle and then discharging this energy into the light emissive diode during another part of the cycle.

Abstract: The method of the invention generates an address signal for addressing columns or rows of a PDP. In the case of addressing a column, for example, the method comprises the following steps. For a phase T1, a DC voltage V1 is applied across the terminals of a solenoid L, so that the latter stores energy, and applies a voltage A across the terminals of a selected column. During a phase T2, some of the energy stored in the solenoid L is discharged into the column until the voltage across the terminals of the column becomes about zero. During a phase T3, an approximately zero voltage is maintained across the terminals of the column. According to one embodiment the selection of the column(s) during this phase is modifiable. During a phase T4, the solenoid L is charged with current stored in a capacitor until the voltage across the terminals of the column is zero.

Abstract: Provided is a device for supplying an array of electrodes of a plasma display panel, the device including, for each electrode, a driver having a series of switches and a series of diodes, the common points of which are connected to the electrode. The upper terminal of the series of diodes is connected directly to the output of a sustain generator and the lower terminal is connected to the sustain generator via a power switch. One of the terminals of the series of switches is connected to the output of a negative voltage generator. In periods during which the negative voltage generator applies a negative voltage to the electrodes, the power switch is open in order to avoid a short-circuit via the diode of the sustain generator.

Abstract: The present invention relates to a device for driving a plasma display panel having a plurality of cells arranged in rows and columns, said device comprising row address means for selectively addressing the display cell rows and creating, where required, in cooperation with means for selectively applying data voltages to the display columns, an electrical discharge inside the cell disposed at the intersection of the row and column selected during an address phase, and sustain means (I3, I4, I5, I6) for sustaining the electrical discharges inside said cell during a sustain phase immediately following the address phase. According to the invention, the row address means and/or the sustain means are capable of allowing a bi-directional current to flow in the display cells during the address and/or sustain phases. The capacitive and light-emission currents appearing during these phases can thus flow freely and do not create electromagnetic interference.

Abstract: The invention relates to a device comprising a metallic support plate, the front face of which supports a plasma discharge panel which is equipped with a network of pairs of adjacent electrodes and the rear face of which is equipped with a power supply. According to the invention, the connection ends of the electrodes of one electrode pair are located on opposite edges of the panel and the power circuit of each pair of adjacent electrodes forms a current loop that does not surround the metallic plate. In this way, electric losses are restricted in said plate and the cells of the panel operate identically along the entire length of the electrodes.

Abstract: An image display device is disclosed including a metallic support plate carrying, on its front face, a plasma discharge display with an array of adjacent pairs of electrodes and, on its back face, a power supply. The power supply circuit of each pair of adjacent electrodes forms a current loop starting from the power supply and passing through the electrode then the electrode of the pair, the connection end of the electrode being linked to the power supply by means of a transverse electrical conductor placed on the front side of said metallic plate. According to the invention, the transverse conductor linked to the electrode forms a non-zero angle with said pair of electrodes. The differences in inductance between the various current loops of the display are thus reduced such that the differences in luminance between the various discharge regions of the plasma display are reduced.

Abstract: The electrodes are used both for the sustain phase and the address phase. The device comprises, for each electrode Yn, a driver 5 comprising a series of switches 51, 52 and a series of diodes 53, 54, the common points of which are connected to this electrode; the upper terminal of the series of diodes is connected directly to the output 92 of a sustain generator 2 and its lower terminal is connected to this same generator via a power switch 6; one of the terminals of the series of switches is connected to the output 94, 97 of a negative voltage generator 4, 7. Thus, in the periods during which the negative voltage generator 4, 7 applies a negative voltage to the electrodes, it suffices to open the power switch 6 in order to avoid a short-circuit via the diode 25 of the sustain generator 2.

Abstract: The present invention relates to a method for controlling an image display device and an image display device implementing this method. The invention relates more specifically to a display device having a matrix of cells, a column driver circuit and a column amplifier with resonant circuitry to recover energy. The invention proposes to optimize the method for controlling the column amplifier to reduce to zero the energy losses during the switching actions of the switches of the column driver circuit. To this end, the invention proposes to position the start of the period of oscillation of the resonant circuit in a manner dependent on the capacitance of the columns of cells connected to the resonant circuit via the column driver circuit such that the switching actions of the switches of the column driver circuit always take place when the voltage delivered by the column amplifier is zero.

Abstract: The method of the invention generates an address signal for addressing columns or rows of a PDP. In the case of addressing a column, for example, the method comprises the following steps. For a phase T1, a DC voltage V1 is applied across the terminals of a solenoid L, so that the latter stores energy, and applies a voltage A across the terminals of a selected column. During a phase T2, some of the energy stored in the solenoid L is discharged into the column until the voltage across the terminals of the column becomes about zero, During a phase T3, an approximately zero voltage is maintained across the terminals of the column. According to one embodiment the selection of the column(s) during this phase is modifiable. During a phase T4, the solenoid L is charged with current stored in a capacitor until the voltage across the terminals of the column is zero.

Abstract: An image display device is disclosed including a metallic support plate carrying, on its front face, a plasma discharge display with an array of adjacent pairs of electrodes and, on its back face, a power supply. The power supply circuit of each pair of adjacent electrodes forms a current loop starting from the power supply and passing through the electrode then the electrode of the pair, the connection end of the electrode being linked to the power supply by means of a transverse electrical conductor placed on the front side of said metallic plate. According to the invention, the transverse conductor linked to the electrode forms a non-zero angle with said pair of electrodes. The differences in inductance between the various current loops of the display are thus reduced such that the differences in luminance between the various discharge regions of the plasma display are reduced.

Abstract: The device comprises a metal support plate 1 supporting, on its front face, a plasma discharge panel provided with an array of pairs of adjacent electrodes 7, 8 and, on its rear face, a supply 13′; according to the invention, the connection ends of the electrodes 7, 8 of the same pair are located on opposed edges 5, 6 of the panel and the supply circuit for each pair of adjacent electrodes 7, 8 then forms a current loop which does not surround the metal plate 1.

Abstract: In computer monitors having a picture tube, it may be seen that a small white picture area is displayed with the same white value as a large white picture area. If it were intended to achieve the same result for a television receiver with a picture tube, a voltage supply is necessary in which the power is permitted to fluctuate between 60 and 300 watts given a stable output voltage. On account of the lower luminous efficiency, this effect would have considerably intensified repercussions on the power consumption of plasma screens. The invention is based on the object of providing a simplified method for regulating the picture power in a television receiver. The method according to the invention is distinguished by the following steps. The power consumption of the picture power is obtained by the video voltage R, G, B. The video voltage is converted into an information item which is then a measure of the picture power. This information item is subsequently fed to two regulating loops.

Abstract: The invention is based on the object of compressing time losses and of improving an enhanced picture display. The method according to the invention of driving a plasma screen which is subdivided into horizontal lines and vertical pixel points, it being possible for the individual pixel points to be driven for different lengths of time, a preparation mode and an addressing mode being provided for driving, is distinguished by the fact that the lines are combined into groups and that, in the groups, the preparation mode and the addressing mode are executed separately, the preparation mode including a priming mode and an erasing mode.

Abstract: The circuit for stabilizing a high voltage for a picture tube comprises a high-voltage transformer, which has a primary winding and a high-voltage winding, a switch, which is connected in series with the primary winding, and a control loop for high-voltage stabilization. The control voltage of the control loop, with which the switch is driven, is derived from two signals in this case. The first signal is tapped off from a secondary auxiliary winding at the transformer and supplies a static control voltage component, and the second signal is derived directly from the high voltage and supplies a measure of the dynamic loading on the high-voltage generator. The static control voltage component is, in particular, a measure of the value of the high voltage during the vertical line flyback, when the screen is black and the high-voltage transformer is minimally loaded. In this case, the auxiliary winding supplies a voltage which is proportional to the secondary flyback pulse.

Abstract: The device comprising a video processing circuit (7) for processing the video data received, a correspondence memory (8) for transcoding these data, a video memory (9) for storing the transcoded data, the video memory being linked to column drivers (10) in order to control the column addressing of the plasma panel on the basis of column control words, a control circuit (11) for the line drivers (12), is characterized in that the control circuit for the line drivers simultaneously selects at least two successive lines during the transmission by the column drivers (10) of at least one of the bits of the column control words relating to one of these lines.

Abstract: The present invention relates to a method of compensating for the differences in persistence of the phosphors in an image display screen consisting of cells arranged in lines and in columns, several adjacent cells being covered with different phosphors in order to form a pixel, the cells of one pixel being put either into an “off” state or into an “on” state for a time within one frame period depending on the grey level to be displayed. According to the method, at the pixel, the transitions between a first grey level and an adjacent second grey level are detected and if the transition is greater than a threshold the state of the cell covered with a persistent phosphor is forced to the second grey level before the end of the frame period. The invention applies especially to plasma panels.

Abstract: A circuit for controlling beam current in a picture tube, which circuit calculates current pictures for the R, G, B beam currents in the picture tube, which largely correspond to real beam currents in the color picture tube. The circuit comprises a comparator/integrator which compares a sum of these current pictures with a beam current information item for the purpose of controlling the R, G, B beam currents and/or the picture sharpness. Gamma correction is carried out in the circuit. The circuit may be of analog or digital construction and may advantageously be integrated in a video processor IC. The present circuit is particularly applicable for television sets or computer monitors.

Abstract: The switched-mode power supply comprises a secondary winding and four diodes for producing two rectified voltages of the same polarity, one of which can be regulated. A connection of the unregulated voltage has connected to it a variable Zener diode as an error amplifier for transmitting a regulating signal to the primary side. The driver stage provides a pulse-width-modulated square-wave signal for driving the switching transistor which is arranged at a high potential between the operating voltage on the input side and a first connection of the primary winding. The second connection of the primary winding is connected with a Zener diode and provides a stabilized voltage for the driver stage. Arranged between the driver stage and the control electrode of the switching transistor there is a differentiating element which produces positive and negative switching voltages for controlling the switching transistor.

Abstract: Transformer comprises a core (K1, K2), a primary winding (W1) and at least one secondary winding (W2), which are arranged as conductors on one or more layers of a flat carrier, and a coil former with a chamber system having chambers (C1, C2), which accommodate the layers with the windings (W1, W2). At least one of the chambers (C1, C2) is closed at least in regions, with the result that long distances for creepage paths are obtained. As a result of this, it is possible to adhere to existing safety regulations for the mains power supply isolation even with very compact dimensions and/or with full utilization of the width available for the conductor tracks. The chamber system can be formed from two or three plastic parts (P1, P2, P3) by mating. The layers with the conductor tracks are routed laterally out of the chamber system in order to make contact with terminals.