KR100612368B1 - Plasma display device and driving method thereof - Google Patents

Abstract

The present invention discloses a plasma display device and a driving method thereof. According to the present invention, in a plasma display device in which one frame is divided into a plurality of subfields, the level of the bias voltage applied to the sustain electrode in the address period of each subfield is varied in response to a temperature change of the plasma display panel. In this case, when the temperature of the plasma display panel is lowered below a predetermined temperature when the plasma display device is driven, low discharge of the address discharge can be prevented and stable discharge can be caused.

Plasma Display, Address Period, Low Discharge, Bias Voltage

Description

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

1 is a view showing a driving waveform diagram of a plasma display device according to the prior art.

2 and 3 are diagrams showing wall charge distribution according to a driving waveform applied to a conventional plasma display device.

4 is an electrode array diagram of a plasma display device according to an exemplary embodiment of the present invention.

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

6 and 7 are driving waveform diagrams of a plasma display device according to an exemplary embodiment of the present invention.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display device and a driving method thereof, and more particularly, to a plasma display device and a driving method thereof capable of preventing the occurrence of address low discharge when the temperature of the plasma display panel is lower than a predetermined temperature.

Plasma display devices are flat display devices that display characters or images using plasma generated by gas discharge, and dozens to millions or more 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.

1 is a driving waveform diagram of a plasma display device according to the prior art. Here, one subfield among the plurality of subfields is described as an example.

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 in which wall charges are accumulated on cells (addressed 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.

2 and 3 are diagrams showing that the wall charge distribution state immediately before the address period according to the driving waveform application of the conventional plasma display device shown in FIG. 1 varies with the temperature change of the plasma display panel. In particular, FIG. 2 illustrates a wall charge distribution immediately before an address when the temperature of the plasma display panel is greater than or equal to a predetermined temperature, and FIG. 3 illustrates a wall charge distribution immediately before an address when the temperature of the plasma display panel is less than a predetermined temperature.

As shown in Fig. 2, when the temperature of the plasma display panel is higher than or equal to the predetermined temperature, the wall charge is set up in a state suitable for address discharge in the address period immediately before the end of the reset period. That is, negative wall charges are accumulated on scan electrode Y, and a large amount of negative wall charges and positive wall charges are accumulated on sustain electrode X and address electrode A, respectively. On the other hand, as shown in FIG. 3, when the temperature of the plasma display panel is lower than the predetermined temperature, the movement of the charges in the plasma state is slowed down, so that the wall charges accumulated at each electrode are less accumulated at room temperature. Therefore, there is a high possibility of low discharge occurring in the address period. In this case, the temperature of the plasma display panel in which low discharge may occur in the address period may be obtained through experiments.

As such, when the temperature of the plasma panel is lowered below a predetermined temperature when the plasma display device is driven, the movement of the charges is slowed down so that wall charges do not accumulate as much as desired on each electrode. In particular, if the wall charges do not accumulate as much as desired on each electrode immediately after the end of the reset period just before the address period, there is a problem in that address discharge is poor due to poor address discharge.

Accordingly, an object of the present invention is to provide a plasma display device and a driving method thereof capable of preventing low discharge that may occur in an address period when the plasma display device is driven while the temperature of the plasma panel is lower than a predetermined temperature. It is to.

According to an aspect of the present invention, a plurality of first electrodes and a plurality of second electrodes, and a plurality of third electrodes formed in a direction crossing the first and second electrodes are provided. In the plasma display panel, a frame is divided into a plurality of subfields including reset, address, and sustain periods.

(a) sensing a temperature of the plasma display panel; (b) resetting the discharge cells to be addressable by applying a voltage gradually rising and gradually falling to the first electrode; And (c) biasing a third voltage to the second electrode when applying a first voltage and a second voltage to the first electrode and the third electrode, respectively, to select a discharge cell to be selected among the discharge cells. Including an address step,

The level of the third voltage biased to the second electrode may be varied according to the temperature of the plasma display panel.

According to another aspect of the present invention, a plasma display device includes 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 first electrode and the second electrode; A panel temperature sensing unit for sensing a temperature of the plasma display panel and a driving circuit for driving one frame into a plurality of subfields each configured of a reset, an address, and a sustain period in the plasma display panel. Apply a voltage gradually rising and gradually decreasing to the first electrode to initialize all of the discharge cells and set them to be addressable, and to select the discharge cells to be selected among the discharge cells to the first electrode and the third electrode. Biasing the third voltage to the second electrode while applying a first voltage and a second voltage, respectively; The level of the third voltage biased to the second electrode may be varied according to the temperature of the display panel.

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 according to an exemplary embodiment of the present invention will be described in detail with reference to the accompanying drawings.

4 illustrates an electrode arrangement diagram of a plasma display panel according to an exemplary embodiment of the present invention.

As shown in Fig. 4, the PDP electrode has a matrix structure of m x n. Specifically, the address electrodes A1 to Am are arranged in the column direction and n rows of scan electrodes Y1 to the row direction. Yn) and sustain electrodes X1 to Xn are arranged.

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

As shown in FIG. 5, a plasma display device according to an exemplary embodiment of the present invention includes a plasma panel 100, an address driver 200, a scan electrode driver 300, a sustain electrode driver 400, and a panel temperature detector 500. ) And the control unit 600.

The plasma panel 100 includes a plurality of address electrodes A1-Am arranged in the column direction, electrodes Y1-Yn (hereinafter referred to as scan electrode Y) arranged in the row direction, and electrodes X1- Xn (hereinafter, referred to as sustain electrode X).

The address driver 200 receives an address driving control signal SA 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 300 and the sustain electrode driver 400 receive the scan electrode drive signal SY and the sustain electrode drive signal SX from the control unit 200, respectively, to the scan electrode Y and the sustain electrode X. Is authorized.

The controller 600 receives an image signal from an external source, generates an address driving control signal SA, a scan electrode driving signal SY, and a sustain electrode driving signal SX, respectively, and generates an address driver 200 and a scan electrode driver ( 300 and the sustain electrode driver 400.

The panel temperature detector 500 detects a temperature of the plasma panel 100 and transmits the temperature to the controller 600. In this case, the period during which the panel temperature sensing unit 500 performs the panel temperature sensing operation may be appropriately changed within a range capable of achieving the object of the present invention. For example, the temperature sensing operation may be performed for every subfield in all subfields of one frame, or the temperature sensing operation may be performed for a predetermined number of subfields. In addition, since the method of sensing the temperature of the plasma display panel 100 by the panel temperature sensing unit 500 is a general technique for those skilled in the art, a detailed description thereof will be omitted. Then, the control unit 600 receives the driving signal varying the level of the bias voltage applied to the sustain electrode X in the address period in response to the temperature of the panel transmitted from the panel temperature sensor 500. Will output

According to the exemplary embodiment of the present invention, when the panel temperature sensing unit 500 connected to the plasma panel 100 senses the temperature of the plasma panel and transmits the temperature information, the controller 400 refers to the predetermined temperature. When the temperature of the plasma panel 100 is lower than the predetermined temperature, the bias voltage Vb 'higher than the temperature Vb of the bias voltage biased to the sustain electrode X may be applied in the address period. The control signal is transmitted to the sustain electrode driver 500. That is, according to the exemplary embodiment of the present invention, the level of the bias voltage for biasing the sustain electrode X in the address period is varied in response to the temperature change of the plasma panel 100.

Hereinafter, a driving waveform of the plasma display device according to an exemplary embodiment of the present invention will be described with reference to FIG. 6. In particular, the driving waveform of the plasma display device applied to the sustain electrode X in the address period will be described. The description of the same parts as in the prior art will be omitted for the driving waveform.

In general, when the temperature of the plasma panel is higher than or equal to a predetermined temperature, an address period is applied to the scan electrode Y, the sustain electrode X, and the address electrode A after the end of the reset period for initializing all discharge cells and setting up wall charges. In order to stably perform the address discharge at, a large amount of negative wall charges and positive wall charges are accumulated.

On the other hand, the wall charge is present in the form of a plasma, the movement of the plasma panel 100 is active or contracted according to the temperature change. For example, as described above, when the temperature of the panel 100 is higher than or equal to a predetermined temperature, the wall charges accumulate as much as a desired amount for the address discharge in the address period after the movement of the wall charges normally ends in the reset period. On the other hand, when the temperature of the panel 100 is lower than the predetermined temperature, the movement of the wall charges in the form of plasma is slowed down, so that the movement of the wall charges due to the discharge is not active, and wall charges do not accumulate as much as desired on each electrode. This results in poor discharge, especially when the desired amount of wall charges cannot accumulate on each electrode after the end of the reset period of initializing all discharge cells and setting up wall charges for stable address discharge in the address period. The discharge in the subsequent address period becomes poor, and address low discharge may occur.

Therefore, the following describes an embodiment of the present invention that can solve this problem with reference to the drawings.

In particular, a driving waveform in which the level of the bias voltage biased to the sustain electrode X in the driving waveform applied in the address period is varied in response to the temperature change of the plasma panel will be described.

6 and 7 are driving waveform diagrams of a plasma display device according to an exemplary embodiment of the present invention. In particular, a diagram showing an example in which the level of the bias voltage biased to the sustain electrode X in the address period is changed in correspondence with the temperature of the plasma panel 100.

6 is a view showing a driving waveform when the temperature of the plasma panel is greater than or equal to a predetermined temperature according to an embodiment of the present invention.

As shown in FIG. 6, the driving method of the plasma display device according to the exemplary embodiment of the present invention is expressed by a change in time and is composed of a reset period, an address period and a sustain period.

The reset period is a period for initializing the state of each cell in order to smoothly perform an address operation on the cell. The address period is an address voltage for a cell (addressed cell) that is turned on to select a cell that is turned on and a cell that is not turned on. It is a period of time to perform the operation of accumulating wall charge by applying a. The sustain period is a period in which a discharge for actually displaying an image in an addressed cell is applied by applying a sustain discharge pulse.

All the discharge cells are discharged by the ramp voltage rising in the reset period, so that a large amount of negative charges are stored in the scan electrode Y, and a large amount of positive charges are stored in the address electrode A.

That is, in the rising period of the reset period, all the cells are discharged by applying a slowly rising voltage to the scan electrode Y. In the falling period, the voltage Vnf is a negative level while the sustain electrode X is biased to a constant voltage. By erasing the wall charges by applying a voltage that gradually descends to, it initializes to the wall charge state suitable for addressing in the next address period. That is, the negative wall charges are sufficiently accumulated on the scan electrode Y and the positive wall charges on the address electrode A.

The address period is a period in which a wall charge is accumulated in a cell (addressed cell) that is turned on by selecting a cell that is turned on and a cell that is not turned on in the panel. In the address period, when scanning in order from the scan electrode Y (applying a voltage VscL lower than the bias voltage VscH biased to the scan electrode Y), the address electrode A is selected to select a cell to be turned on. ) Is applied to the positive address voltage Va. Then, the address is caused by the difference between the address voltage Va applied to the address electrode A and the voltage VscL applied to the scan electrode and the wall voltage formed by the wall charges formed on the address electrode A and the scan electrode Y. Discharge occurs to form a wall voltage on the scan electrode Y and the sustain electrode X. At this time, when the temperature of the plasma panel 100 is greater than or equal to a predetermined temperature, the voltage Vb is biased to the sustain electrode X. Then, following the discharge between the scan electrode Y and the address electrode A, a discharge occurs between the scan electrode Y and the sustain electrode X, so that address discharge occurs stably.

Next, the sustain period is a period in which sustain discharge for actually displaying an image in the addressed cell 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.

7 is a view showing a driving waveform when the temperature of the plasma panel is less than a predetermined temperature according to an embodiment of the present invention.

As shown in FIG. 7, when the temperature of the plasma panel 100 is lower than the predetermined temperature, the driving waveform of the plasma display device according to the exemplary embodiment of the present invention is equal to or greater than the predetermined temperature. The level of the bias voltage biased to the sustain electrode X in the address period is different.

Referring to FIG. 7, when the temperature of the plasma panel 100 is lower than the predetermined temperature, since the wall charges do not accumulate as much as desired after the end of the reset period, the bias voltage is biased to the sustain electrode X in the address period. When the temperature of the plasma panel 100 of FIG. 6 is higher than or equal to a predetermined temperature, the level of Vb 'is higher than the level of the bias voltage Vb biased to the sustain electrode X in the address period. By doing so, the address discharge is prevented from occurring when the temperature of the plasma panel 100 is lower than the predetermined temperature to prevent address discharge.

As described with reference to FIGS. 6 and 7, the level of the bias voltage biased to the sustain electrode X in the address period may vary in response to the temperature of the plasma panel 100 sensed by the panel temperature sensing unit 500.

As described above, according to the exemplary embodiment of the present invention, the temperature of the plasma display panel 100 is varied by varying the level of the bias voltage biased to the sustain electrode X in the address period of each subfield according to the temperature change of the plasma panel 100. When the plasma display device is driven at a temperature lower than a predetermined temperature, low discharge in the address period can be prevented.

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 present invention defined in the following claims are also provided. It belongs to the scope of rights.

As described above, according to the exemplary embodiment of the present invention, the temperature of the plasma panel is sensed when the plasma display device is driven to vary the level of the bias voltage biased to the sustain electrode X in the address period according to the temperature of the panel. When the temperature of the plasma panel is lower than a predetermined temperature, that is, a temperature at which low discharge may occur in the address period, address low discharge in the address period may be prevented.

Claims (6)

In 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 first electrode and the second electrode, one frame may be reset, addressed, and sustained, respectively. In the driving method divided into a plurality of configured subfields, (a) sensing a temperature of the plasma display panel; (b) resetting the discharge cells to be addressable by applying a voltage gradually rising and gradually falling to the first electrode; And (c) an address for biasing a third voltage to the second electrode when applying a first voltage and a second voltage to the first electrode and the third electrode, respectively, to select a discharge cell to be selected among the discharge cells; Steps, The level of the third voltage biased to the second electrode when the temperature of the plasma display panel is lower than the predetermined temperature is higher than the level of the third voltage biased to the second electrode when the temperature of the plasma display panel is higher than the predetermined temperature. Driving method of high plasma display device. delete The method of claim 1, And biasing the third voltage to the second electrode while applying a voltage that gradually falls to the first electrode. 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 first electrode and the second electrode; A panel temperature detector configured to detect a temperature of the plasma display panel; And A driving circuit for driving one frame into a plurality of subfields each consisting of a reset, an address, and a sustain period in the plasma display panel; The driving circuit Initializing and setting all discharge cells to be addressable by applying a voltage gradually rising and gradually falling to the first electrode, and the first electrode and the third electrode to select a discharge cell to be selected among the discharge cells. Biasing a third voltage to the second electrode while applying a first voltage and a second voltage to the second electrode; The level of the third voltage biased to the second electrode when the temperature of the plasma display panel is lower than the predetermined temperature is the level of the third voltage biased to the second electrode when the temperature of the plasma display panel is higher than the predetermined temperature. Higher plasma display device. delete The method of claim 4, wherein And biasing the third voltage to the second electrode while applying a voltage that gradually falls to the first electrode.

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