KR100667361B1 - Plasma display apparatus - Google Patents

Abstract

A plasma display device is provided to increase might emitting efficiency by preventing an erroneous discharge of a plasma display device having a long-gap structure, and to enhance the driving efficiency by reducing power consumption. A plasma display device includes a plasma display panel(600), a scan driver(63), a data driver(62), a sustain driver(64), a timing controller(61), and a driving voltage generator(65). The plasma display panel includes scan, sustain, and address electrodes. The scan driver includes a first driving unit, which applies a sustain-up voltage including a rising ramp voltage to the scan electrodes. The data driver includes a second driving unit, which applies a positive voltage on the address electrodes, while the set-up voltage is applied on the scan electrodes. The sustain driver drives the sustain electrode, which serves as a common electrode. The timing controller controls the first and second driving units. The driving voltage generator supplies driving voltages to the respective drivers.

Description

Plasma display apparatus

1 is a perspective view showing the structure of a typical plasma display panel.

2 is a diagram illustrating a method of implementing image grayscale of a conventional plasma display device.

3 is a view showing driving waveforms of a conventional plasma display device.

4 is a diagram showing a distribution of a discharge start voltage according to a distance between discharge electrodes.

5 is a diagram illustrating a process of changing a cell voltage according to a distance between discharge electrodes.

6 illustrates a plasma display device according to an exemplary embodiment of the present invention.

7 to 14 show driving waveforms of the plasma display device according to the present invention;

FIG. 15 is a diagram illustrating a process of changing a cell voltage during a set up period in the present invention. FIG.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display device, and more particularly, to a plasma display device which prevents erroneous discharge and improves driving efficiency.

In general, a plasma display panel forms a unit cell with a space between partition walls formed between a front substrate and a rear substrate, and each cell includes neon (Ne), helium (He), or a mixture of neon and helium (Ne +). A main discharge gas such as He) and an inert gas containing a small amount of xenon are filled. When discharged by a high frequency voltage, the inert gas generates vacuum ultraviolet rays and emits phosphors formed between the partition walls to realize an image. Plasma display devices employing such plasma display panels have been spotlighted as next generation display devices because they can be made thin and light.

1 is a perspective view showing the structure of a general plasma display panel.

As shown in FIG. 1, the plasma display panel is coupled in parallel with a front substrate 100, which is a display surface on which an image is displayed, and a rear substrate 110, which forms a rear surface, with a predetermined distance therebetween.

The front substrate 100 is based on the front glass 101, and scan electrodes 102 (Y electrodes) and sustain electrodes 103 (Z electrodes), that is, mutually discharged in one discharge cell and maintain light emission of the cells. The scan electrode 102 and the sustain electrode 103 formed of a transparent electrode a made of a transparent ITO material and a bus electrode b made of a metal material are formed in pairs. Scan electrode 102 and sustain electrode 103 are covered by one or more dielectric layers 104 that limit the discharge current and insulate the electrode pairs, and on top of dielectric layer 104 to facilitate discharge conditions. A protective layer 105 on which magnesium oxide (MgO) is deposited is formed.

The rear substrate 110 is arranged with the stripe-type (or well-type) partition walls 112 to form a plurality of discharge spaces, that is, discharge cells, based on the rear glass 111. In addition, a plurality of address electrodes 113 (X electrodes) for performing address discharge to generate vacuum ultraviolet rays are disposed in parallel with the partition wall 112. The upper surface of the rear substrate 110 is coated with R, G, B phosphors 114 that emit visible light for image display during address discharge. A white dielectric 115 is formed between the address electrode 113 and the phosphor 114 to protect the address electrode 113 and reflect the visible light emitted from the phosphor 114 to the front substrate 100.

A method of implementing gray levels of an image in the plasma display device employing the plasma display panel is shown in FIG. 2.

2 is a diagram illustrating a method of implementing image grayscale of a conventional plasma display device.

As shown in FIG. 2, in the conventional method of expressing a gray level of a plasma display panel, a frame is divided into several subfields having a different number of emission times, and each subfield is a reset period (RPD) for initializing all cells. ) Is divided into an address period APD for selecting a cell to be discharged and a sustain period SPD for implementing gradation according to the number of discharges. For example, when a picture is to be displayed with 256 gray levels, a frame period (16.67 ms) corresponding to 1/60 second is divided into eight subfields SF1 to SF8, and eight subfields SF1 to SF8) are each divided into a reset period, an address period, and a sustain period.

The reset period and the address period of each subfield are the same for each subfield. The address discharge for selecting the cell to be discharged is caused by the voltage difference between the address electrode and the scan electrode. The sustain period is increased at a rate of 2 ⁿ (n = 0, 1, 2, 3, 4, 5, 6, 7) in each subfield. As described above, since the sustain period is different in each subfield, the gray scale of the image is expressed by adjusting the sustain period of each subfield, that is, the number of sustain discharges. The driving waveform of the plasma display device employing the plasma display panel is shown in FIG. 3.

3 illustrates a driving waveform of a conventional plasma display device.

As shown in FIG. 3, the conventional plasma display device is divided into a reset period for initializing all cells, an address period for selecting a cell to be discharged, and a sustain period for maintaining discharge of the selected cell.

In the reset period, the rising ramp waveform is simultaneously applied to all the scan electrodes in the setup period. This rising ramp waveform causes weak dark discharge in the discharge cells of the entire screen. By this setup discharge, positive wall charges accumulate on the address electrode and the sustain electrode, and negative wall charges accumulate on the scan electrode.

In the set-down period, after the rising ramp waveform is supplied, the falling ramp waveform begins to fall from the positive polarity voltage lower than the peak voltage of the rising ramp waveform and falls to a specific voltage level below the ground (GND) level. By causing the discharge, the wall charges excessively formed on the scan electrodes are sufficiently erased.

By this set-down discharge, wall charges such that the address discharge can stably occur remain uniformly in the cells.

In the address period, a negative polarity scan signal is sequentially applied to the scan electrodes, and a data signal of a positive polarity is applied to the address electrode in synchronization with the scan signal. As the voltage difference between the scan signal and the data signal and the wall voltage generated in the reset period are added, an address discharge is generated in the discharge cell to which the data signal is applied. In the cells selected by the address discharge, wall charges are formed such that a discharge can occur when the sustain voltage Vs is applied. The sustain electrode is supplied with a positive polarity voltage Vzb during the set down period and the address period so as to reduce the voltage difference with the scan electrode so that the discharge electrode does not have an error discharge.

In the sustain period, a sustain signal Su is alternately applied to the scan electrode and the sustain electrodes. In the cell selected by the address discharge, as the wall voltage and the sustain signal in the cell are added, a sustain discharge, that is, a display discharge occurs between the scan electrode and the sustain electrode every time the sustain signal is applied.

In this way, the driving process of the plasma display device in one subfield is completed.

On the other hand, in order to improve the luminance of the plasma display device, the light emitting efficiency is improved by increasing the distance between the discharge electrodes and enlarging both light-emitting regions, but increasing the distance between the discharge electrodes causes an increase in the driving voltage, which causes bright spots during the reset process. Increasing the probability causes a false discharge, while increasing the amount of power consumed acts as a cause of lowering the driving efficiency.

These problems will be described in more detail using the hexagonal voltage curve (Vt-Curve) used for the discharge generation principle and voltage margin measurement of the plasma display panel.

4 is a diagram showing the distribution of discharge start voltages according to the distance between discharge electrodes.

The horizontal axis represents the relative voltage difference between the sustain electrode Z and the scan electrode Y, and the vertical axis represents the relative voltage difference between the address electrode X and the scan electrode Y.

The area inside the hexagonal voltage curve is the area where the wall charges in the discharge cell are distributed. In this area, no discharge occurs.

Vf1 displayed in the three-quadrant discharge region of the voltage curve indicates a voltage at which discharge starts between the scan electrode Y and the sustain electrode Z when the distance between the scan electrode Y and the sustain electrode Z is relatively short. . When the distance between the Vf2 scan electrode Y and the sustain electrode Z is relatively long, the voltage at which discharge starts between the scan electrode Y and the sustain electrode Z is shown.

As can be seen from FIG. 4, the discharge start voltage also increases in proportion to the difference in distance between the scan electrode Y and the sustain electrode Z. FIG.

This may be expressed as Equation 1 below.

, Vf1 is a voltage at which discharge is initiated between the scan electrode Y and the sustain electrode Z when the distance between the scan electrode Y and the sustain electrode Z is relatively short, and Vf2 is the scan electrode Y and the sustain electrode ( When the distance between Z is relatively long, the voltage at which the discharge starts between the scan electrode Y and the sustain electrode Z is shown.

As can be seen from Equations 1 and 4, it can be seen that a difference ΔV of the discharge start voltage occurs depending on the distance between the scan electrode Y and the sustain electrode Z.

5 is a diagram illustrating a process of changing the cell voltage when the rising ramp waveform is applied to the scan electrode Y according to the distance between the discharge electrodes.

In FIG. 5, point A represents the wall voltage immediately after the last sustain pulse is applied to the sustain electrode.

Thereafter, a rising ramp waveform of positive polarity is supplied to the scan electrode (Y). When the rising ramp waveform of positive polarity is supplied to the scan electrode Y, the cell voltage moves along the three-quadrant surface discharge region in the direction of the arrow shown from the point A. Here, when the cell voltage reaches the boundary value of the surface discharge region of the three quadrants, the surface discharge occurs between the scan electrode Y and the sustain electrode Z.

At this time, when the distance between the scan electrode (Y) and the sustain electrode (Z) is relatively short, surface discharge occurs at the point A '.

On the other hand, when the distance between the scan electrode Y and the sustain electrode Z is relatively long, surface discharge occurs at the point A ".

In this case, as shown in the drawing, the point A ″ is a region where the surface discharge and the counter discharge have a high probability of coexistence, and an undesired counter discharge between the scan electrode Y and the address electrode X is generated to increase the luminance of the plasma display device. On the other hand, there is a problem that causes an incomplete discharge and causes instability of the entire driving process.

SUMMARY OF THE INVENTION An object of the present invention is to provide a plasma display device which prevents erroneous discharge during a driving process of a plasma display panel having a long gap structure and improves driving efficiency.

The plasma display device of the present invention for achieving the above object comprises a scan electrode and a sustain electrode formed on two transparent electrodes spaced apart from 90 ㎛ to 200 ㎛ and an address electrode formed in a direction crossing the electrodes A plasma display panel, a first driver applying a setup voltage including a rising ramp voltage to the scan electrode, and a second driver applying a positive voltage to the address electrode while the setup voltage is applied to the scan electrode, The maximum value of the positive voltage may be greater than or equal to 1.5 times or less than the magnitude of the data pulse voltage applied to the address electrode.

The maximum value of the positive voltage is characterized by being at least 1 and at most 1.5 times the magnitude of the data pulse voltage applied to the address electrode.

The positive voltage may be a spherical pulse voltage or a ramp pulse voltage.

The positive voltage may be applied before the setup voltage.

The positive voltage may be applied in synchronization with the setup voltage.

In addition, a plasma display device driving method according to the present invention includes a scan electrode and a sustain electrode formed on two transparent electrodes spaced apart from 90 μm to 200 μm and an address electrode formed in a direction crossing the electrodes. Applying a setup voltage including a rising ramp voltage to the scan electrode of the panel and applying a positive voltage to the address electrode while the setup voltage is applied to the scan electrode, wherein the maximum value of the positive voltage is 1 to 1.5 times the magnitude of the data pulse voltage applied to the address electrode.

The maximum value of the positive voltage is characterized by being at least 1 and at most 1.5 times the magnitude of the data pulse voltage applied to the address electrode.

The positive voltage may be a spherical pulse voltage or a ramp pulse voltage.

The positive voltage may be applied before the setup voltage.

The positive voltage may be applied in synchronization with the setup voltage.

Hereinafter, with reference to the accompanying drawings will be described a preferred embodiment of the present invention;

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

As shown in FIG. 6, a plasma display device according to an exemplary embodiment of the present invention has a scan electrode, a sustain electrode, and a direction intersecting the electrodes and the scan electrode formed on two transparent electrodes spaced from 90 μm to 200 μm. A scan driver 63 including a plasma display panel 600 including an formed address electrode, a first driver 63A applying a setup voltage including a rising ramp voltage to the scan electrodes Y1 to Yn, A data driver 62 including a second driver 62A for applying a positive polarity voltage to the address electrodes X1 to Xm while the setup voltage is applied to the scan electrodes Y1 to Yn, and a sustain as a common electrode. Sustain driver 64 for driving electrode Z, timing controller 61 for controlling each driver 62, 63, 64, and drive voltage for supplying a drive voltage to each driver 62, 63, 64. And a generator 65.

The plasma display panel 600 is bonded to the front panel (not shown) and the rear panel (not shown) at regular intervals, and a plurality of electrodes, for example, scan electrodes Y1 to Yn and a sustain electrode, are attached to the front panel. (Z) are formed in pairs, and address electrodes X1 to Xm are formed on the rear panel to intersect the scan electrodes Y1 to Yn and the sustain electrode Z.

On the other hand, the separation distance between the transparent electrode of the scan electrode and the transparent electrode of the scan electrode is a light emission by actively using both positive column in the process of applying a voltage to the surface scan electrode and the sustain electrode to generate a surface discharge for image display In order to increase efficiency, it is set to 90 m or more and 200 m or less.

As a result of enlarging the separation distance between the scan electrode and the sustain electrode, the separation distance between the scan electrode and the sustain electrode is considerably enlarged and discharge is relatively larger than the separation distance between the scan electrode and the address electrode and the separation distance between the sustain electrode and the address electrode. The voltages applied to the respective electrodes are also adjusted as described below.

The scan driver 63 applies a setup voltage including a rising ramp voltage that gradually rises to the scan electrodes Y1 to Yn to initialize the entire screen during the reset period under the control of the timing controller 61. The drive part 63A is included.

In addition, after the setup voltage is applied, the scan driver 63 applies a descending ramp voltage gradually decreasing to the scan electrode.

In addition, the scan driver 63 may scan scan voltages (-Vsc) and scan pulses to the scan electrodes (Y1 to Yn) to select scan lines during the address period after the reset waveforms are supplied to the scan electrodes (Y1 to Yn). Supply (-Vy).

In addition, the scan driver 63 supplies a sustain pulse to the scan electrodes Y1 to Yn to allow sustain discharge to occur in the selected cell in the address period during the sustain period.

The data driver 62 is subjected to inverse gamma correction and error diffusion by an inverse gamma correction circuit, an error diffusion circuit, and the like not shown, and then data mapped to a subfield pattern preset by the subfield mapping circuit is supplied. The data driver 62 samples and latches data under the control of the timing controller 61, and then supplies the data to the address electrodes X1 to Xm.

The data driver 62 includes a second driver 62A for applying a positive polarity voltage to the address electrode while the setup voltage is applied to the scan electrode.

The sustain driver 64 supplies the positive polarity Z-bias voltage Vzb to the sustain electrode Z during the address period under the control of the timing controller 61, and then alternately operates the scan driver 63 during the sustain period. The sustain pulse is supplied to the sustain electrode Z.

The timing controller 61 receives the vertical / horizontal synchronization signal and generates timing control signals CTRX, CTRY, and CTRZ required for each driving unit, and transmits the timing control signals CTRX, CTRY, and CTRZ to the corresponding driving units 62, 63, and the like. Each drive unit 62, 63, 64 is controlled by supplying it to 64). The timing control signal CTRX applied to the data driver 62 includes a sampling clock for sampling data, a latch control signal, an energy recovery circuit, and a switch control signal for controlling on / off time of the driving switch element. The timing control signal CTRY applied to the scan driver 63 includes an energy recovery circuit in the scan driver 63 and a switch control signal for controlling on / off time of the driving switch element. The timing control signal CTRZ applied to the sustain driver 64 includes a switch control signal for controlling the on / off time of the energy recovery circuit and the drive switch element in the sustain driver 64.

The driving voltage generator 65 is applied to the address electrode during the sustain voltage Vs, the Z-bias voltage Vzb, the data voltage Va, the scan voltage (-Vy), the scan reference voltage (-Vsc), and the reset period. Various driving voltages required by each of the driving units 62, 63, and 64, including the positive polarity voltage Vx, are generated. These driving voltages may vary depending on the composition of the discharge gas or the structure of the discharge cell.

Hereinafter, a detailed driving process of the plasma display device according to an exemplary embodiment of the present invention will be described in detail with reference to FIG. 7 showing a driving waveform and FIG. 15 showing a process of changing a cell voltage during a set-up period.

7 illustrates a driving waveform of the plasma display device according to an exemplary embodiment.

As shown in FIG. 7, a plasma display device according to an exemplary embodiment includes a reset period for initializing all cells, an address period for selecting a cell to be discharged, and a sustain period for maintaining discharge of the selected cell. Driven separately.

First in the reset period,

In the setup period, a setup voltage including a rising ramp voltage is simultaneously applied to all scan electrodes. This setup voltage causes a weak dark discharge in the discharge cells of the entire screen. By this setup discharge, positive wall charges accumulate on the address electrode and the sustain electrode, and negative wall charges accumulate on the scan electrode.

This process is described in more detail as follows. That is, during the set-up period, all the scan electrodes start at the first voltage Vs and ascend to the second voltage Vs + Vst with a predetermined slope, maintain equilibrium for a predetermined time, and then fall vertically to the first voltage Vs. The setup voltage including the rising ramp voltage is applied, the sustain electrode maintains the ground, and the positive polarity square pulse voltage Vx is applied to the address electrode.

The reason why the positive polarity square pulse voltage Vx is applied to the address electrode during the set-up period is that the separation distance between the scan electrode and the address electrode is relatively shorter than the separation distance between the scan electrode and the sustain electrode.

In other words, in the present invention having a long gap structure in which the separation distance between the scan electrode and the sustain electrode is greatly expanded, an externally applied voltage for generating a discharge between the scan electrode and the sustain electrode is also increased, and thus, a setup period. The risk of erroneous discharge between the scan electrode and the address electrode is increased.

Therefore, while the positive rising ramp voltage is applied to the scan electrode during the set-up period, the positive rectangular pulse voltage Vx is also applied to the address electrode to reduce the potential difference between the scan electrode and the sustain electrode to prevent mis-discharge.

In this way, by actively participating in the discharge process during the set-up period during the reset period, that is, by applying a square pulse voltage having a positive polarity to the address electrode, the false discharge is prevented, thereby improving the brightness of the plasma display device and driving. Improve the efficiency.

The discharge process of the plasma display device will be described in more detail with reference to FIG. 15, which illustrates a process of changing the cell voltage.

15 is a diagram illustrating a process of changing a cell voltage during a set up period.

In Fig. 15, the A1 point indicates the state of the wall voltage immediately after the last sustain pulse is applied to the sustain electrode.

Subsequently, during the setup period, a setup voltage including a rising ramp waveform of positive polarity is applied to the scan electrode Y. When a positive polarity voltage such as a square pulse voltage is applied to the address electrode, the cell voltage moves to the point A2. .

That is, the wall voltage at point A1 and the externally applied voltage Vx of positive polarity applied to the address electrode are added to move to point A2.

Subsequently, when a setup voltage including a rising ramp waveform is applied to the scan electrode, the cell voltage moves along the direction of the solid arrow shown.

At the moment when the sum of the wall voltage Vw at the point A2 and the setup voltage Vs + Vst applied from the outside exceeds the discharge start voltage Vw + V ₂ ′, that is, at the point A22 of FIG. The setup discharge in the form of surface discharge between the sustain electrodes occurs stably.

If the address electrode remains grounded during the setup period, the cell voltage moves along the direction of the dotted line arrow when the setup voltage including the rising ramp waveform is applied to the scan electrode.

The scan electrode and the sustain at the moment when the sum of the wall voltage Vw at the point A1 and the setup voltage Vs + Vst applied from the outside exceeds the discharge start voltage Vw + V ₂ , that is, at the point A11 of FIG. 15. Surface discharge between the electrodes occurs.

However, as shown in FIG. 15, the A11 point is adjacent to the counter discharge region, and thus, an area in which an unintentional counter discharge between the scan electrode and the address electrode is unintentionally generated during the setup process is high.

In general, considering that the opposite discharge has the characteristics of a strong discharge having a high light emission amount, the unintentional generation of the undesired opposite discharge serves as a major factor for lowering the luminance of the plasma display device.

Therefore, in the driving process of the plasma display device according to the present invention, the positive polarity square pulse voltage Vx is applied to the address electrode before the setup voltage is applied, so that the scan electrode and the address electrode during the setup process are not intended. To prevent the occurrence of unopposed discharges.

That is, the surface discharge generation point between the scan electrode and the sustain electrode is moved from the point A11 to the point A22 to prevent the occurrence of unintentional counter discharge between the scan electrode and the address electrode.

In addition, as shown in FIG. 15, the size of the setup voltage applied to the scan electrode may be reduced by moving the surface discharge occurrence point between the scan electrode and the sustain electrode from the point A11 to the point A22. .

This may be expressed as Equation 2 below.

V ₂ Is the minimum value of the setup voltage required for the scan electrode for setup discharge at point A11, and V ₂ ′ is the minimum voltage of the setup voltage required for the scan electrode for setup discharge at point A22.

As can be seen from Equation 2 and FIG. 15, the surface discharge occurrence point between the scan electrode and the sustain electrode is applied at the point A11 at the point A22 by applying a positive polarity square pulse voltage Vx to the address electrode before the setup voltage is applied. By moving to the point, the minimum value of the setup voltage required for the scan electrode to generate the setup discharge can be lowered by ΔＶ ₂ .

The magnitude Vx of the rectangular pulse voltage is preferably 1 or more and 1.5 times or less than the data pulse voltage magnitude Va applied to the address electrode during the address period.

In this way, by controlling the magnitude (Vx) of the positive-polarity spherical pulse voltage applied to the address electrode during the setup period, the mis-discharge of the plasma display device can be prevented more efficiently, and the driving efficiency is improved.

Then during the set down period when the falling ramp voltage is applied,

When the falling ramp voltage is applied to the scan electrode and the sustain electrode and the address electrode maintain the ground state, the positive polarity wall charge of the address electrode is maintained, but the positive polarity wall charge of the sustain electrode is erased through the discharge between the sustain electrode and the scan electrode. The sustain electrode and the scan electrode divide a large amount of negative polarity charges accumulated on the scan electrode.

By this set-down discharge, wall charges such that the address discharge can stably occur remain uniformly in the cells.

Next in the address period,

When the data pulse voltage Va of positive polarity is applied to the address electrode and the scan pulse voltage of negative polarity (-Vy) is applied to the scan electrode in synchronization, the voltage difference Va + Vy between the address electrode and the scan electrode and during the reset period As the wall voltage Vw between the address electrode and the scan electrode due to the formed wall charge is added, the address discharge is stably generated to secure the driving margin of the display device.

On the other hand, the positive polarity voltage Vzb is supplied to the sustain electrode such that the voltage difference with the scan electrode is reduced during the address period so that no misdischarge occurs with the scan electrode.

Next, in the sustain period,

The sustain signal is alternately applied to the scan electrode and the sustain electrodes. In the cell selected by the address discharge, as the wall voltage and the sustain signal in the cell are added, a sustain discharge, that is, a display discharge occurs between the scan electrode and the sustain electrode every time the sustain signal is applied.

 As shown in FIG. 8, in the driving process of the plasma display device according to the present invention, the positive polarity square pulse voltage applied to the address electrode during the set-up period is synchronized with the application timing of the setup voltage applied to the scan electrode. Appropriate measures can also be taken.

In this manner, by applying a square pulse voltage of positive polarity to the address electrode in synchronization with the time when the setup voltage rising vertically from the ground to the first voltage Vs is applied to the scan electrode, the potential difference between the scan electrode and the address electrode is reduced and thus As a result, an incorrect discharge between the scan electrode and the address electrode, that is, an unintended counter discharge between the scan electrode and the address electrode during the set up period is prevented.

In addition, as shown in FIGS. 9 and 10, a method of applying a ramp pulse voltage having a positive polarity to the address electrode during the set up period may also be devised.

In consideration of the fact that the rising ramp pulse voltage is applied to the scan electrode during the set-up period, a counter pulse between the scan electrode and the address electrode is applied to the address electrode by applying a ramp pulse voltage having a slope corresponding to the slope of the ramp voltage applied to the scan electrode. To prevent them more efficiently.

11 to 14, a method of applying a positive bias voltage Vzb to the sustain electrode during the set down period during which the falling ramp voltage is applied to the scan electrode may be devised.

By applying the positive bias voltage Vzb to the sustain electrode during the set-down period as described above, it is possible to reduce the excessive potential difference between the scan electrode and the sustain electrode to improve the luminance of the plasma display device and to stably generate a subsequent address discharge. The degree of wall charge is formed in the cell.

In this way, the driving process of the plasma display device according to the present invention in one subfield is completed.

As described above in detail, the present invention has a wide distance between transparent electrodes in order to improve luminous efficiency. For example, in the driving process of a plasma display device including a plasma display panel spaced apart from 90 μm to 200 μm, the address electrode By actively participating in the setup discharge, it is possible to prevent the erroneous discharge such as bright spots to improve the luminous efficiency, while reducing the power consumption to provide a plasma display device that improves the driving efficiency.

Hereinafter, a driving method of the plasma display device according to the present invention will be described in detail with reference to FIGS. 7 to 15.

7 illustrates a driving waveform in a method of driving a plasma display device according to an exemplary embodiment of the present invention.

As shown in FIG. 7, in the method of driving a plasma display device according to an exemplary embodiment, a reset period for initializing all cells, an address period for selecting a cell to be discharged, and maintaining a discharge of the selected cell are maintained. It is divided into sustain periods for driving.

First in the reset period,

In the setup period, a setup voltage including a rising ramp voltage is simultaneously applied to all scan electrodes. This setup voltage causes a weak dark discharge in the discharge cells of the entire screen. By this setup discharge, positive wall charges accumulate on the address electrode and the sustain electrode, and negative wall charges accumulate on the scan electrode.

This process is described in more detail as follows. That is, during the set-up period, all the scan electrodes start at the first voltage Vs and ascend to the second voltage Vs + Vst with a predetermined slope, maintain equilibrium for a predetermined time, and then fall vertically to the first voltage Vs. The setup voltage including the rising ramp voltage is applied, the sustain electrode maintains the ground, and the positive polarity square pulse voltage Vx is applied to the address electrode.

The reason why the positive polarity square pulse voltage Vx is applied to the address electrode during the set-up period is that the separation distance between the scan electrode and the address electrode is relatively shorter than the separation distance between the scan electrode and the sustain electrode.

In other words, in the present invention having a long gap structure in which the separation distance between the scan electrode and the sustain electrode is greatly expanded, an externally applied voltage for generating a discharge between the scan electrode and the sustain electrode is also increased, and thus, a setup period. The risk of erroneous discharge between the scan electrode and the address electrode is increased.

Therefore, while the positive rising ramp voltage is applied to the scan electrode during the set-up period, the positive rectangular pulse voltage Vx is also applied to the address electrode to reduce the potential difference between the scan electrode and the sustain electrode to prevent mis-discharge.

In this way, by actively participating in the discharge process during the set-up period during the reset period, that is, by applying a square pulse voltage having a positive polarity to the address electrode, the false discharge is prevented, thereby improving the brightness of the plasma display device and driving. Improve the efficiency.

The discharge process according to the driving method of the plasma display device according to the present invention will be described in more detail with reference to FIG. 15.

15 is a diagram illustrating a process of changing a cell voltage during a set up period.

In Fig. 15, the A1 point indicates the state of the wall voltage immediately after the last sustain pulse is applied to the sustain electrode.

Subsequently, during the setup period, a setup voltage including a rising ramp waveform of positive polarity is applied to the scan electrode Y. When a positive polarity voltage such as a square pulse voltage is applied to the address electrode, the cell voltage moves to the point A2. .

That is, the wall voltage at point A1 and the externally applied voltage Vx of positive polarity applied to the address electrode are added to move to point A2.

Subsequently, when a setup voltage including a rising ramp waveform is applied to the scan electrode, the cell voltage moves along the direction of the solid arrow shown.

At the moment when the sum of the wall voltage Vw at the point A2 and the setup voltage Vs + Vst applied from the outside exceeds the discharge start voltage Vw + V ₂ ′, that is, at the point A22 of FIG. The setup discharge in the form of surface discharge between the sustain electrodes occurs stably.

If the address electrode remains grounded during the setup period, the cell voltage moves along the direction of the dotted line arrow when the setup voltage including the rising ramp waveform is applied to the scan electrode.

The scan electrode and the sustain at the moment when the sum of the wall voltage Vw at the point A1 and the setup voltage Vs + Vst applied from the outside exceeds the discharge start voltage Vw + V ₂ , that is, at the point A11 of FIG. 15. Surface discharge between the electrodes occurs.

However, as shown in FIG. 15, the A11 point is adjacent to the counter discharge region, and thus, an area in which an unintentional counter discharge between the scan electrode and the address electrode is unintentionally generated during the setup process is high.

In general, considering that the opposite discharge has the characteristics of a strong discharge having a high light emission amount, the unintentional generation of the undesired opposite discharge serves as a major factor for lowering the luminance of the plasma display device.

Therefore, in the method of driving the plasma display device according to the present invention, as described above, the positive polarity square pulse voltage Vx is applied to the address electrode before the setup voltage is applied. To prevent the occurrence of unopposed discharges.

That is, the surface discharge generation point between the scan electrode and the sustain electrode is moved from the point A11 to the point A22 to prevent the occurrence of unintentional counter discharge between the scan electrode and the address electrode.

In addition, as shown in FIG. 15, the size of the setup voltage applied to the scan electrode may be reduced by moving the surface discharge occurrence point between the scan electrode and the sustain electrode from the point A11 to the point A22. .

This may be expressed as Equation 3 below.

V ₂ is the minimum value of the setup voltage required for the scan electrode for setup discharge at point A11, and V ₂ ′ is the minimum voltage of the setup voltage required for the scan electrode for setup discharge at point A22.

As can be seen from Equation 3 and FIG. 15, the surface discharge occurrence point between the scan electrode and the sustain electrode is applied at the point A11 at the point A22 by applying a positive polarity square pulse voltage Vx to the address electrode before the setup voltage is applied. By moving to the point, the minimum value of the setup voltage required for the scan electrode to generate the setup discharge can be lowered by ΔＶ ₂ .

It is preferable that the magnitude Vx of the rectangular pulse voltage is one or more and 1.5 times or less than the data pulse voltage magnitude Va applied to the address electrode during the address period.

In this way, by controlling the magnitude (Vx) of the positive-polarity spherical pulse voltage applied to the address electrode during the setup period, the mis-discharge of the plasma display device can be prevented more efficiently, and the driving efficiency is improved.

Then during the set down period when the falling ramp voltage is applied,

When the falling ramp voltage is applied to the scan electrode and the sustain electrode and the address electrode maintain the ground state, the positive polarity wall charge of the address electrode is maintained, but the positive polarity wall charge of the sustain electrode is erased through the discharge between the sustain electrode and the scan electrode. The sustain electrode and the scan electrode divide a large amount of negative polarity charges accumulated on the scan electrode.

By this set-down discharge, wall charges such that the address discharge can stably occur remain uniformly in the cells.

Next in the address period,

When the data pulse voltage Va of positive polarity is applied to the address electrode and the scan pulse voltage of negative polarity (-Vy) is applied to the scan electrode in synchronization, the voltage difference Va + Vy between the address electrode and the scan electrode and during the reset period As the wall voltage Vw between the address electrode and the scan electrode due to the formed wall charge is added, the address discharge is stably generated to secure the driving margin of the display device.

On the other hand, the positive polarity voltage Vzb is supplied to the sustain electrode such that the voltage difference with the scan electrode is reduced during the address period so that no misdischarge occurs with the scan electrode.

Next, in the sustain period,

The sustain signal is alternately applied to the scan electrode and the sustain electrodes. In the cell selected by the address discharge, as the wall voltage and the sustain signal in the cell are added, a sustain discharge, that is, a display discharge occurs between the scan electrode and the sustain electrode every time the sustain signal is applied.

 As shown in FIG. 8, in the driving method of the plasma display device according to the present invention, the positive polarity square pulse voltage applied to the address electrode during the set up period is synchronized with the application timing of the setup voltage applied to the scan electrode. Appropriate measures can also be taken.

In this manner, by applying a square pulse voltage of positive polarity to the address electrode in synchronization with the time when the setup voltage rising vertically from the ground to the first voltage Vs is applied to the scan electrode, the potential difference between the scan electrode and the address electrode is reduced and thus As a result, an incorrect discharge between the scan electrode and the address electrode, that is, an unintended counter discharge between the scan electrode and the address electrode during the set up period is prevented.

In addition, as shown in FIGS. 9 and 10, a method of applying a ramp pulse voltage having a positive polarity to the address electrode during the set up period may also be devised.

In consideration of the fact that the rising ramp pulse voltage is applied to the scan electrode during the set-up period, a counter pulse between the scan electrode and the address electrode is applied to the address electrode by applying a ramp pulse voltage having a slope corresponding to the slope of the ramp voltage applied to the scan electrode. To prevent them more efficiently.

11 to 14, a method of applying a positive bias voltage Vzb to the sustain electrode during the set down period during which the falling ramp voltage is applied to the scan electrode may be devised.

By applying the positive bias voltage Vzb to the sustain electrode during the set-down period as described above, it is possible to reduce the excessive potential difference between the scan electrode and the sustain electrode to improve the luminance of the plasma display device and to stably generate a subsequent address discharge. The degree of wall charge is formed in the cell.

In this way, the driving process by the driving method of the plasma display device according to the present invention in one subfield is completed.

As described in detail above, the present invention provides a method of driving a plasma display device including a plasma display panel having a wide distance between transparent electrodes, for example, 90 μm or more and 200 μm or less, for improving luminous efficiency. By actively participating in the setup discharge, it is possible to prevent the erroneous discharge, such as bright spots to improve the luminous efficiency, while reducing the power consumption to provide a driving method of the plasma display device.

As described above, the technical configuration of the present invention described above will be understood by those skilled in the art that the present invention can be implemented in other specific forms without changing the technical spirit or essential features of the present invention. .

Therefore, the exemplary embodiments described above are to be understood as illustrative and not restrictive in all respects, and the scope of the present invention is indicated by the following claims rather than the detailed description, and the meaning and scope of the claims and All changes or modifications derived from the equivalent concept should be interpreted as being included in the scope of the present invention.

As described in detail above, the present invention actively participates in the addressing discharge, thereby preventing erroneous discharge when driving the plasma display panel having a long gap structure, thereby improving luminous efficiency and consuming. A plasma display device for improving driving efficiency by reducing power is provided.

Claims (10)

A plasma display panel including a scan electrode, a sustain electrode, and an address electrode formed in a direction intersecting the electrodes; A first driver configured to apply a setup voltage including a rising ramp voltage to the scan electrode; A second driver configured to apply a positive voltage to the address electrode while the setup voltage is applied to the scan electrode, And the maximum value of the positive polarity voltage is not less than 1 and not more than 1.5 times the magnitude of the data pulse voltage applied to the address electrode. delete The method of claim 1, And said positive voltage is a square pulse voltage or a ramp pulse voltage. The method of claim 1, And wherein the positive voltage is applied before the set-up voltage. The method of claim 1, The positive voltage is applied in synchronization with the setup voltage. delete delete delete delete delete

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