KR100648687B1 - Plasma display device and driving method thereof - Google Patents

Abstract

A plasma display device and a driving method thereof are provided to restrict low discharge during an address period by applying pre-scan pulse to a scan electrode right before the address period if the temperature of a plasma display panel or the peripheral temperature is high. A method for driving a plasma display device having a plasma display panel(100) comprising plural first electrodes(Y1~Yn), plural second electrodes(X1~Xn), and plural third electrodes(A1~Am) formed across the first and second electrodes includes a step of detecting the temperature of the plasma display panel and a step of applying a first voltage with a first pulse width to the first electrodes during a first period between a reset period and an address period if the detected temperature is higher than a predetermined temperature value.

Description

Plasma display and driving method {PLASMA DISPLAY DEVICE AND DRIVING METHOD THEREOF}

1 is a view showing a schematic configuration of a plasma display device according to an embodiment of the present invention.

2 is a diagram illustrating an operation of a controller according to an exemplary embodiment of the present invention.

3 is a driving waveform diagram of a plasma display device at a high temperature according to the first embodiment of the present invention.

 4A and 4B are diagrams illustrating wall charge distribution according to application of a driving waveform to a plasma display device.

5 is a driving waveform diagram of a plasma display device at a high temperature according to a second exemplary embodiment of the present invention.

The present invention relates to a plasma display device and a driving method thereof.

Plasma display devices are flat display devices that display characters or images using plasma generated by gas discharge, and dozens to millions of pixels are arranged in a matrix form according to their size.

In a typical plasma display device driving method, one frame is divided into a plurality of subfields, and a gray level is expressed by a combination of subfields. Each subfield consists of a reset period, an address period, and a sustain period.

The reset period serves to erase the wall charge state of the previous sustain discharge and to set up wall charge in order to stably perform the next address discharge.

The address period is a period during which the wall charges are accumulated in the cells that are turned on by selecting cells that are turned on and cells that are not turned on in the panel.

The sustain period is a period in which discharge for actually displaying an image on the addressed cells is performed.

In this case, the wall charge refers to a charge formed in the wall of the discharge cell (eg, the dielectric layer) close to each electrode and accumulated in the electrode. Such wall charges are not actually in contact with the electrodes themselves, but here wall charges are described as "formed", "accumulated" or "stacked" on the electrodes. In addition, wall voltage refers to the potential difference formed in the wall of a discharge cell by wall charge.

On the other hand, when the temperature of the plasma display panel or the ambient temperature is higher than the predetermined temperature, the formation conditions of the magnesium oxide (MgO) covering the scan electrode Y and the sustain electrode X may change sensitively depending on the plasma display panel temperature. Therefore, low discharge may occur in the address period.

Accordingly, an object of the present invention is to provide a plasma display device and a driving method thereof for preventing low discharge in an address period generated when a temperature is high.

According to one feature of the present invention for achieving the above object, a plurality of first electrodes, a plurality of second electrodes and a plurality of third electrodes formed in a direction crossing the plurality of first and second electrodes A method of driving a plasma display device including a plasma display panel is provided. The driving method includes sensing a temperature of the plasma display panel; If the sensed temperature is a first temperature that is higher than a predetermined temperature, applying a first voltage having a first pulse width to the plurality of first electrodes in a first period between a reset period and an address period. .

A plasma display device according to another aspect of the present invention includes a plurality of first electrodes, a plurality of second electrodes, and a plurality of third electrodes formed in a direction crossing the plurality of first and second electrodes. panel; A temperature sensing unit sensing a temperature of the plasma display panel; And when the temperature transmitted from the temperature sensor is a first temperature higher than a predetermined temperature, apply a first voltage having a first pulse width to the plurality of first electrodes in a first period between a reset period and an address period. It includes a control unit for controlling to.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention. Like parts are designated by like reference numerals throughout the specification.

Hereinafter, a plasma display device and a driving method thereof according to an exemplary embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a diagram illustrating a plasma display device according to an exemplary embodiment of the present invention.

As shown in FIG. 1, a plasma display device according to an exemplary embodiment of the present invention includes a plasma display panel 100, a controller 200, an address electrode driver 300, a scan electrode driver 400, and a sustain electrode driver 500. And a temperature sensing unit 600.

The plasma display panel 100 includes a plurality of address electrodes A1 to Am extending in the column direction, and a plurality of sustain electrodes X1 to Xn and scan electrodes Y1 to Yn extending in pairs in the row direction. Include. The sustain electrodes X1 to Xn are formed corresponding to the scan electrodes Y1 to Yn, and generally have one end connected to each other in common. The plasma display panel 100 includes a substrate (not shown) on which the sustain and scan electrodes X1 to Xn and Y1 to Yn are arranged, and a substrate (not shown) on which the address electrodes A1 to Am are arranged. The two substrates are disposed to face each other with the discharge space therebetween so that the scan electrodes Y1 to Yn and the address electrodes A1 to Am and the sustain electrodes X1 to Xn and the address electrodes A1 to Am are orthogonal to each other. At this time, the discharge space at the intersection of the address electrodes A1 to Am and the sustain and scan electrodes X1 to Xn and Y1 to Yn forms a discharge cell. The structure of the plasma display panel 100 is an example, and a panel having another structure to which the driving waveform described below may be applied may also be applied to the present invention.

The controller 200 receives an image signal from the outside and outputs an address electrode A driving control signal, a sustain electrode X driving control signal, and a scan electrode Y driving control signal. The controller 200 divides and drives one frame into a plurality of subfields, and each subfield is composed of a reset period, an address period, and a sustain period. At this time, the control unit 200 may apply a pre-scan pulse to the scan electrode Y immediately before the address period according to the temperature of the plasma display panel 100 received from the temperature sensing unit 600 or the ambient temperature of the plasma display panel. Outputs a control signal.

The address electrode driver 300 receives the address electrode A driving control signal from the controller 200 and applies a display data signal for selecting a discharge cell to be displayed to each address electrode.

The scan electrode driver 400 receives the scan electrode Y driving control signal from the controller 200 and applies a driving voltage to the scan electrode Y.

The sustain electrode driver 500 receives the sustain electrode X driving control signal from the controller 200 and applies a driving voltage to the sustain electrode X.

The temperature detector 600 detects the temperature of the plasma display panel 100 or the temperature around the plasma display panel and transmits the detected temperature to the controller 200. Hereinafter, the temperature sensing unit 600 will be described as sensing the temperature of the plasma display panel for convenience. However, it is natural that the temperature sensing unit 600 can measure the temperature of not only the plasma display panel but also other parts.

Next, an operation of the controller 200 in the plasma display device according to an exemplary embodiment of the present invention will be described in detail with reference to FIG. 2.

FIG. 2 is a diagram illustrating an operation of the controller shown in FIG. 1.

As shown in FIG. 2, the controller 200 receives the temperature of the plasma display panel 100 sensed by the temperature sensor 600 and compares the temperature with a predetermined temperature (S410-S420).

At this time, if the sensed temperature is greater than or equal to the predetermined temperature, the controller 200 outputs a control signal for applying the pre-scan pulse Vb to the scan electrode Y immediately before the address period (S430).

On the other hand, when the sensed temperature is less than the predetermined temperature, the controller 200 outputs a general control signal to which the prescan pulse Vb is not applied (S440).

The control signal output from the controller 200 is input to the scan electrode driver 400 to control the wall voltage between the address electrode and the scan electrode immediately before the address period (S450). Here, the predetermined temperature may be obtained through an experimental method as the temperature of the point where the low discharge occurs in the address period, and the detailed description thereof will be omitted since it will be readily understood by those skilled in the art. Generally, the predetermined temperature is measured at about 60 ° C.

Next, a driving method of the plasma display device according to the first embodiment of the present invention will be described in detail with reference to FIGS. 3, 4A, and 4B.

3 is a driving waveform diagram of a plasma display device at a high temperature according to a first embodiment of the present invention, and FIGS. 4A to 4B are diagrams showing wall charge distribution states according to application of a driving waveform of the plasma display device shown in FIG. to be.

In FIG. 3, one subfield of the plurality of subfields is described as an example. In FIG. 3, only driving waveforms applied to one of the plurality of scan electrodes, the sustain electrodes, and the address electrodes Y, the sustain electrodes X, and the address electrodes A are illustrated.

As shown in Fig. 3, each subfield consists of a reset period, an address period, and a sustain period, and the reset period consists of a rising period and a falling period.

The reset period is a period of initializing the state of each cell in order to perform an address operation smoothly on the cell. The address period is a wall charge by applying an address voltage to a cell to be turned on and a cell to be turned on to select a cell that is not turned on. This is the period during which the stacking operation is performed. The sustain period is a period in which a discharge for actually displaying an image in the addressed cells by applying a sustain discharge pulse is performed.

In the period of rise in the reset period, all the discharge cells are discharged by the gradually rising voltage, so that a large amount of negative charge is accumulated in the scan electrode Y, and a large amount of positive (+) in the address electrode A. Charges accumulate, and in the falling period, a large amount of negative charges accumulated on the scan electrode Y are erased by the voltage gradually falling.

That is, in the rising period of the reset period, a gentle rising voltage is applied to the scan electrode Y to discharge all the cells, and in the falling period, a negative level is applied while the sustain electrode X is biased to a constant voltage. By erasing the wall charges by applying a voltage that gradually falls to the voltage Vnf, it is initialized to a wall charge state suitable for addressing in the next address period.

Next, in the address period, a scan pulse having a VscL voltage is sequentially applied to the scan electrode Y to select a discharge cell, and the scan electrode to which the VscL voltage is not applied is biased to the VscH voltage. At this time, the VscL voltage is called a scan voltage and the VscH voltage is also called a non-scan voltage. In addition, an address pulse having a Va voltage is applied to an address electrode A passing through a discharge cell to be selected from among a plurality of discharge cells formed by the scan electrode Y to which the VscL voltage is applied. A) biases to a reference voltage (0V in FIG. 3). Then, an address discharge occurs in the discharge cell formed by the address electrode A applied with the Va voltage and the scan electrode Y with the VscL voltage, and positive wall charges are formed on the scan electrode Y. A negative wall charge is formed in the sustain electrode X. In addition, a negative wall charge is formed on the address electrode A as well.

On the other hand, when the plasma display panel 100 or the temperature around it is high, the formation conditions of magnesium oxide (MgO) covering the scan electrode Y and sustain electrode X are sensitively changed depending on the plasma display panel temperature. In the address period, low discharge may occur. In particular, in the case of the scan electrode to which the scan pulse is applied late, the wall charges accumulated on the scan electrode Y and the sustain electrode X are lost to the space between the scan electrode and the sustain electrode, so that address discharge cannot be performed properly.

In Fig. 3, the wall charge state immediately after the end of the reset period is as shown in Fig. 4A.

That is, before the reset period ends and before the scan pulse is applied, predetermined (-) wall charges are formed on the scan electrode (Y) and sustain electrode (X), and predetermined (+) wall charges are applied to the address electrode (A). It is initialized to the formed state.

On the other hand, when the temperature of the plasma display panel 100 is higher than the predetermined temperature, the wall charge state is as shown in FIG. 4B immediately after the end of the reset period.

That is, before the reset period ends and before the scan pulse is applied, if the temperature is high, a large amount of wall charges are lost to the spaces between the electrodes, so that the scan electrode Y and the address electrode A are connected to the plasma display panel 100. When the temperature is lower than the predetermined temperature, a smaller amount of negative wall charge and positive wall charge are initialized, respectively.

Therefore, when the temperature of the plasma display panel 100 or the surroundings is high, the amount of wall charges is lost, so as to compensate for this, as shown in FIG. 3, a pulse width is applied to the scan electrode Y immediately before the address period. A pre-scan pulse Vb voltage of T is applied to the scan electrode so that the wall charge state similar to that of FIG. 4A is set.

In particular, in the case of the scan electrode Y, a large amount of negative wall charges are accumulated as shown in FIG. 4A before the scan pulse is applied in the address period, when a scan pulse having a negative VscL voltage is applied. This can cause address discharge more stably. Therefore, in the case of high temperature, the wall charges are not properly accumulated in the address period.

Accordingly, when the temperature of the plasma display panel 100 is lower than the predetermined temperature, since the wall charges are sufficiently formed in the address electrode A and the scan electrode Y as shown in FIG. 4A, it is not necessary to apply the Vb voltage. That is, when the temperature of the plasma display panel 100 is lower than or equal to a predetermined temperature, as shown in FIG. 2, the controller 200 applies a general control signal to the scan electrode driver 400 so as not to apply a Vb voltage to the scan electrode Y. Output (S440).

On the other hand, when the temperature of the plasma display panel 100 is higher than the predetermined temperature, wall charges are lost between the address electrode A and the scanning electrode Y as shown in FIG. Unlike the case shown in FIG. 3, the voltage Vb should be applied immediately before the address period to compensate for this. Therefore, when the temperature of the plasma display panel 100 is greater than or equal to a predetermined temperature, as illustrated in FIG. 2, the control unit 200 may apply the prescan pulse Vb to the scan electrode Y immediately before the address period of the scan electrode driver 400. The control signal to be applied is output (S430).

At this time, the voltage level of Vb is determined in response to the difference between the sensed temperature and the predetermined temperature. For example, if the detected temperature is higher by the first temperature difference that is relatively higher than the predetermined temperature, the Vb1 voltage level is applied, and when the detected temperature is higher by the second temperature difference that is relatively smaller than the predetermined temperature, the Vb2 voltage lower than the Vb1 voltage level Is applied. That is, the higher the temperature of the plasma display panel 100 or the surroundings thereof, the greater the probability that low discharge occurs between the scan electrode Y and the address electrode A, thereby compensating for this by adjusting the Vb voltage level. Therefore, address discharge between scan electrode Y and address electrode A is caused to occur stably, and low discharge is prevented in address operation.

Next, the sustain period is a period in which sustain discharge for actually displaying an image in the addressed cells is performed. A sustain discharge pulse having a Vs voltage and a 0V voltage is alternately applied to the scan electrode Y and the sustain electrode X to cause sustain discharge in the selected cell in the address period.

In this case, when the temperature of the plasma display panel 100 is higher than a predetermined temperature, preventing low discharge between the scan electrode Y and the address electrode A may control not only the Vb voltage level but also the pulse width of the Vb voltage. There is also.

Therefore, the following describes a method of adjusting the pulse width of the Vb voltage to prevent address low discharge.

5 is a driving waveform diagram of a plasma display device at a high temperature according to a second exemplary embodiment of the present invention.

Since the second embodiment of the present invention is the same except that the Vb voltage pulse width is adjusted instead of the Vb voltage level according to the temperature in the first embodiment, the overlapping description is omitted.

That is, the pulse width T of the Vb voltage is determined in response to the difference between the sensed temperature and the predetermined temperature. That is, as the detected temperature is larger than the predetermined temperature, the pulse width T of the Vb voltage increases. For example, when the sensed temperature is the first temperature greater than the predetermined temperature, a Vb voltage having a pulse width of T1 is applied, and when the sensed temperature is greater than the predetermined temperature and less than the first temperature, the pulse width is less than T1. Apply a voltage of Vb, which is T2. That is, the higher the temperature of the plasma display panel 100 or the surroundings thereof, the greater the probability that low discharge occurs between the scan electrode Y and the address electrode A, so that the Vb voltage pulse width is made wider, Compensate for the time that space charge can accumulate on the scan electrode (Y) or the address electrode (A).

At this time, the voltage Vb is lower than the discharge start voltage, and the number of power sources can be reduced by using the same voltage as the voltage Vs which is the sustain discharge voltage.

3 and 5 show that the Vb voltage is applied to the address period, but may be included in the reset period if it is made before the address operation.

Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the invention defined in the following claims are also provided. It belongs to the scope of rights.

As described above, according to the embodiment of the present invention, when the plasma display panel or the temperature around it is high, low discharge in the address period can be prevented by applying a pre-scan pulse to the scan electrode immediately before the address period. .

Claims (9)

A method of driving a plasma display device comprising a plasma display panel including a plurality of first electrodes, a plurality of second electrodes, and a plurality of third electrodes formed in a direction crossing the plurality of first and second electrodes. In Sensing a temperature of the plasma display panel; If the sensed temperature is a first temperature that is higher than a predetermined temperature, applying a first voltage having a first pulse width to the plurality of first electrodes in a first period between a reset period and an address period; A method of driving a plasma display device. The method of claim 1, And when the second temperature, which is the difference between the sensed temperature and the predetermined temperature, increases, the level of the first voltage also increases. The method of claim 1, And increasing the magnitude of the first pulse width when the second temperature, which is a difference between the sensed temperature and a predetermined temperature, increases. The method of claim 1, And the level of the first voltage is the same as the voltage level of the sustain discharge pulses applied to the plurality of first and second electrodes in the sustain period. The method of claim 1, And the first voltage is applied to the plurality of first electrodes before an address voltage is applied to the plurality of third electrodes. A plasma display panel including a plurality of first electrodes, a plurality of second electrodes, and a plurality of third electrodes formed in a direction crossing the plurality of first and second electrodes; A temperature sensing unit sensing a temperature of the plasma display panel; And When the temperature transmitted from the temperature sensing unit is a first temperature higher than a predetermined temperature, the first voltage having the first pulse width is applied to the plurality of first electrodes in the first period between the reset period and the address period. Plasma display device including a control unit for controlling. The method of claim 6, The control unit, And increasing the level of the first voltage when the second temperature, which is a difference between the sensed temperature and a predetermined temperature, increases. The method of claim 6, The control unit, And increasing the magnitude of the first pulse width when the second temperature, which is a difference between the sensed temperature and a predetermined temperature, increases. The method of claim 6, And the level of the first voltage is the same as the voltage level of the sustain discharge pulses applied to the plurality of first and second electrodes in the sustain period.

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