KR100615271B1 - Driving method of plasma display panel - Google Patents

Abstract

An object of the present invention is to provide a method of driving a plasma display panel that performs stable sustain discharge and improves the discharge efficiency of sustain discharge.

In order to achieve the above object, according to the present invention, each subfield has a reset period, a mixed driving period, and a correction sustain period, and the display electrode line pairs, which are pairs of the sustain electrode line and the scan electrode line, have two or more display electrode lines. Group into pair groups,

The mixed driving period includes two or more group address periods for sequentially performing addressing for each group, and one or more group sustain periods for performing sustain discharge between the group address periods, and the correction sustain period includes each of the subfields. According to the gray-scale weight value of the display electrode line pair groups, the selective sustain period in which the sustain discharge is selectively performed for each group so that the number of sustain discharges coincide with each other, and the common sustain period in which the sustain discharge is performed in common for all the groups. And a first sustain pulse and a second sustain pulse having a rising slope, reaching a first voltage, having a falling slope, and reaching a ground voltage in a common sustain period, respectively, all scan electrode lines and all sustain electrode lines. Are applied alternately to each other and have a first voltage at the first sustain pulse and the second sustain pulse. Provides a method of driving a plasma display panel characterized in that the overlap in the time.

Description

Driving method of plasma display panel {Driving method of plasma display panel}

1 shows a conventional address display separation driving scheme for scan electrode lines.

2 is a timing for explaining an example of a conventional driving signal for driving a three-electrode plasma display panel.

3 is a timing diagram for describing in detail the driving signal of the sustain discharge period of FIG. 2.

4 is a diagram illustrating a method of driving address display mixing according to an embodiment of the present invention.

FIG. 5 is a diagram illustrating in detail a driving process of the first subfield SF1 of FIG. 4.

6 is a view illustrating in detail a driving process of the fourth subfield SF4 of FIG. 4.

FIG. 7 is a timing diagram illustrating a driving process of the fourth subfield SF4 of FIG. 6 as a driving signal.

FIG. 8 is a timing diagram for describing in detail the driving signal of the common sustain period of FIG. 7.

FIG. 9 illustrates a method of driving address display mixing according to another embodiment of the present invention.

FIG. 10 is a view illustrating in detail a driving process of the first subfield SF1 of FIG. 9.

FIG. 11 is a view illustrating in detail a driving process of the fourth subfield SF4 of FIG. 9.

<Explanation of symbols for the main parts of the drawings>

A1, ..., Am ... address electrode lines,

X1, ..., Xn ... holding electrode lines,

Y1, ..., Yn ... scanning electrode lines,

XYG1, XYG2 ... first and second display electrode line pair groups,

R1, ..., R8 ... reset periods,

M1, ..., M8 ... mixed drive periods,

C1, ..., C8 ... calibration maintenance periods,

AS1, ..., AS8 ... selective retention periods,

CS1, ..., CS8 ... common retention periods,

Vs ... first voltage, Vset ... second voltage,

Vset + Vs ... third voltage, Vnf ... fourth voltage,

Vb ... fifth voltage, Vsch ... sixth voltage,

Vscl ... 7th voltage, Va ... 8th voltage,

Vm ... ninth voltage.

The present invention relates to a method of driving a plasma display panel having a three-electrode structure.

Japanese Laid-Open Patent Publication No. 1999-120924 discloses a structure of a conventional plasma display panel. That is, address electrode lines, dielectric layers, scan electrode lines, sustain electrode lines, phosphor layers, barrier ribs, and magnesium monoxide (MgO) protective layers are provided between the front and back substrates of a conventional plasma display panel.

The address electrode lines are formed in a predetermined pattern on the front side of the back substrate. The back dielectric layer is applied to the front of the address electrode lines. In the front of the rear dielectric layer, barrier ribs are formed in a direction parallel to the address electrode lines. These partitions partition the discharge area of each discharge cell and serve to prevent optical interference between the discharge cells. The phosphor layer is applied in front of the rear dielectric layer on the address electrode lines between the partition walls, and a red light emitting phosphor layer, a green light emitting phosphor layer, and a blue light emitting phosphor layer are sequentially disposed.

The sustain electrode lines and the scan electrode lines are formed in a constant pattern on the rear side of the front substrate so as to be orthogonal to the address electrode lines. Each intersection sets a corresponding display cell. Each sustain electrode line and each scan electrode line may be formed by combining a transparent electrode line of a transparent conductive material such as indium tin oxide (ITO) and a metal electrode (bus electrode) line for increasing conductivity. The front dielectric layer is formed by coating the entire surface behind the sustain electrode lines and the scan electrode lines. A protective layer for protecting the panel from a strong electric field, for example, a magnesium monoxide (MgO) layer is formed by applying the entire surface to the rear of the front dielectric layer layer. The plasma forming gas is sealed in the discharge space.

In order to drive the three-electrode structure, a conventional ADS (Address Display Separation) driving method is generally used, which will be described with reference to FIG. 1.

1 shows a conventional address display separation driving scheme for scan electrode lines.

Referring to the drawings, a unit frame may be divided into a predetermined number, for example, eight subfields SF1, ..., SF8 to realize time division gray scale display. Further, each subfield SF1, ... SF8 is divided into a reset section (not shown), an address section A1, ..., A8, and a sustain discharge section S1, ..., S8. .

In each address section A1, ..., A8, a display data signal is applied to the address electrode lines and scan pulses corresponding to each of the scan electrode lines Y1, ..., Yn are sequentially applied.

After each address period A1, ..., A8 ends, in each sustain discharge period S1, ..., S8, the scan electrode lines Y1, ..., Yn and the sustain electrode lines X1. The sustain pulses are alternately applied to ..., Xn), causing sustain discharge in the discharge cells in which wall charges are formed in the address sections A1, ..., A8.

The luminance of the plasma display panel is proportional to the number of sustain discharge pulses in the sustain discharge sections S1, ..., S8 occupied in the unit frame, and one frame forming one image is represented by eight subfields and 256 gray levels. In this case, each subfield may be assigned a number of different sustain pulses in a ratio of 1, 2, 4, 8, 16, 32, 64, and 128 in order. In this case, in order to obtain the luminance of 133 gray levels, cells may be addressed and sustained and discharged during the subfield 1 period, the subfield 3 period, and the subfield 8 period.

The number of sustain discharges allocated to each subfield can be variably determined according to the weights of the subfields according to the APC (Automatic Power Control) step, and can be variously modified in consideration of gamma characteristics or panel characteristics.

2 is a timing for explaining an example of a conventional driving signal for driving a three-electrode plasma display panel. One subfield SF includes a reset period PR, an address period PA, and a sustain discharge period PS.

First, the reset period PR applies a reset pulse to all the scan electrode lines Y1,..., And Yn to perform reset discharge, thereby initializing the wall charge state of all the discharge cells. The reset period PR is carried out before entering the address period PA, which is carried out over the entire screen, thus making it possible to create a fairly even and evenly distributed wall charge arrangement. To this end, as shown in FIG. 2, the ground voltage Vg is first applied to the scan electrode lines Y1,..., And Yn, and then the sustain discharge voltage Vs is applied, and the sustain discharge voltage Vs is applied. The rising ramp signal is applied to reach the highest rising voltage (Vset + Vs), which is increased by the rising voltage (Vset), and then rapidly falls to the sustain discharge voltage (Vs), and the ramp ramp signal from the sustain discharge voltage (Vs). Is applied to reach the lowest falling voltage (Vnf). The ground voltage Vg is applied to the address electrode lines A1, A2, ..., Am during the reset period PR, and the falling ramp signal is applied to the sustain electrode lines X1, ..., Xn. The bias voltage Vb is continuously applied from time to time.

Next, in the address period PA, in order to select a cell to be turned on, a bias voltage Vb is applied to the sustain electrode lines X1, ..., Xn, and the scan electrode lines Y1,. The scan high voltage Vsch is applied to Yn, and the scan pulses having the scan low voltage Vscl are sequentially applied to the scan electrode lines Y1, ..., Yn. A display data signal having an address voltage Va is applied to the address electrode lines A1, A2, ..., Am. As the scan pulse and the display data signal are applied, address discharge is performed in the selected discharge cell.

Next, in the sustain discharge period PS, the sustain electrode lines X1,..., Xn and the scan electrode lines Y1, so that the sustain discharge is performed in the cell to be turned on selected in the address period PA. ..., and a sustain pulse having a sustain discharge voltage Vs is applied alternately. The sustain pulse has a rising slope and reaches a sustain discharge voltage, and has a falling slope and reaches a ground voltage. Referring to FIG. 3, the sustain pulse applied to the scan electrode Y has a rising slope from time ta to tb and finally reaches the sustain discharge voltage Vs, and continues to discharge from time tb to tc. Maintain the voltage (Vs). It has a falling slope from time tc to td and finally reaches ground voltage (Vg) and continues to have ground voltage from time td to tg. The sustain pulse applied to the sustain electrode X is applied with a ground voltage from time ta to td, has a rising slope from time td to te, and finally reaches the sustain discharge voltage Vs, from time te to tf. The sustain discharge voltage Vs is continuously applied, has a falling slope to tg at a time tf, and finally reaches the ground voltage Vg. As shown in FIG. 3, a sustain pulse in which no section having a common sustain discharge voltage Vs is present is alternately applied to the scan electrode Y and the sustain electrode X. The sustain discharge is performed by the wall charge accumulated in the discharge cell selected by the address discharge and the applied sustain discharge voltage Vs. Plasma is formed from the plasma forming gas of the discharge cells which perform the sustain discharge, and the phosphors of the discharge cells are excited by ultraviolet radiation from the plasma to generate light.

Meanwhile, as shown in FIG. 3, there is no section in which the sustain discharge voltage overlaps the scan electrodes and the sustain electrodes in time, which is referred to as a sustain pulse of a non-overlapping waveform. When the sustain pulse of the non-overlapping waveform is applied, for example, the sustain discharge does not occur during the period from the time tb to the time td, and the discharge efficiency decreases, and the sustain discharge period for performing the sustain discharge must be long. The problem arises.

On the other hand, the conventional ADS (Address Display Separation) driving method for driving a plasma display panel having a three-electrode structure performs addressing in the sustain discharge period only after addressing all the scan electrode lines sequentially during the address period for each subfield. This is done. In order to realize a plasma display panel of high quality, according to a trend of increasing the number of scanning electrode lines, an address period increases as the number of scanning electrode lines increases, and wall charges accumulated by address discharge in the discharge cells in which addressing is performed first are performed. There is a problem that a smooth maintenance discharge is not performed in the maintenance discharge period is disturbed.

The present invention is to solve the above problems, in the method of driving a plasma display panel having a three-electrode structure, to improve the problem in the address display separation driving method to perform a stable sustain discharge, and also An object of the present invention is to provide a method of driving a plasma display panel in which discharge efficiency and brightness of sustain discharge are also improved.

In order to achieve the above object, the present invention, the display electrode line pairs of the pair of the sustain electrode line and the scan electrode line are formed side by side, the plasma is formed so that the address electrode lines are spaced apart and cross the display electrode line pairs For the display panel, a plurality of subfields are included in a unit frame to perform gradation display by time division driving, wherein each subfield has a reset period, a mixed driving period, a correction sustain period, and two or more display electrode line pairs. A driving method of a plasma display panel driven by grouping display electrode line pair groups,

The mixed driving period may include two or more group address periods for sequentially performing addressing for each display electrode line pair group; And one or more group sustain periods in which sustain discharge is performed on the addressed display electrode line pair groups between the group address periods.

The correction sustain period may include a selective sustain period in which sustain discharge is selectively performed on the display electrode line pair groups so that the number of sustain discharges in all the display electrode line pair groups coincides with the gray scale weight value of each subfield; And a common sustain period in which sustain discharge is performed in common for all display electrode line pair groups.

In a common sustain period, a first sustain pulse and a second sustain pulse having a rising slope and reaching a first voltage and having a falling slope and reaching a ground voltage are respectively present in all scan electrode lines and all sustain electrode lines. A method of driving a plasma display panel is applied alternately, and a section having a first voltage in a first sustain pulse and a second sustain pulse overlaps in time.

According to another aspect of the present invention, the reset period,

A rising ramp signal is applied to all of the scan electrode lines at a first voltage to finally reach a third voltage rising by a second voltage, and a falling ramp signal is applied at a first voltage to finally reach a fourth voltage. The fifth voltage may be applied to the sustain electrode lines, and the ground voltage may be applied to all address electrode lines.

According to another feature of the invention, the mixing drive period,

In the group address periods, a sixth voltage is applied to the scan electrodes of each group of display electrode line pairs, and a scan pulse having a seventh voltage is sequentially applied, and the display having the eighth voltage according to the scan pulse is applied to the address electrodes. A data signal is applied, a fifth voltage is applied to all sustain electrodes,

In the group sustain periods, a first voltage may be applied to all scan electrodes and a ground voltage may be applied to all sustain electrodes.

According to still another feature of the present invention, in the selective retention period,

In order to equalize the number of sustain discharges per display electrode line pair group, first, a first voltage and a ground voltage are sequentially applied to all sustain electrodes, and scan electrodes of the display electrode line pair group do not have to be sustained discharged. The ninth voltage and the first voltage may be sequentially applied, and the ground voltage and the first voltage may be sequentially applied to the scan electrodes of the display electrode line pair group to which sustain discharge is further performed.

According to another feature of the invention, the magnitude of the ninth voltage is preferably smaller than the magnitude of the first voltage.

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

4 illustrates a method of driving address display mixing according to an embodiment of the present invention. As in the case of the embodiment of FIG. 4, display electrode line pairs, which are pairs of sustain electrode lines and scan electrode lines, may be grouped into two display electrode line pair groups. For example, as shown in the drawing, the display panel is divided from the first display electrode line pair group XYG1 to the second display electrode line pair group XYG2 in the lower direction.

Reference numerals SF1 to SF8 denote subfields allocated within the unit frame, XYG1 to XYG2 denote display electrode line pair groups as reference for driving objects, R1 to R8 for reset times, and M1 to M8 for respective group addresses. Periods and mixed driving periods having respective group sustain periods which come between the respective group address periods, C1 to C8 indicate correction sustain periods. AS1 to AS8 indicate selected sustain periods provided in each correction sustain period, and CS1 to CS8 indicate common sustain periods provided in each correction sustain period, respectively.

At the reset times R1 to R8, the charge states of all the discharge cells become uniform.

The mixed drive periods M1 to M8 have two group address periods and one group sustain period. Addressing, that is, address discharge, is performed for each display electrode line pair group in each group address period, and sustain discharge is performed for each display electrode line pair group in the group sustain period between the group address periods.

The correction sustain periods C1 to C8 include the selective sustain periods AS1 to AS8 and the common sustain periods CS2 to CS8. In the selection sustain periods AS1 to AS8, the display electrode line pairs are selectively selected so that the number of sustain discharges in each display electrode line pair group is the same by correcting the difference in the number of sustain discharges displayed for each display electrode line pair group in the mixed driving period. Perform maintenance discharge on the group. The common sustain period CS1 to CS8 compares the number of sustain discharges up to the selected sustain period with the number of sustain discharges according to the gray scale weight value so that the insufficient number of sustain discharges is performed in common for all display electrode line pair groups. Here, when one frame forming one image is represented by eight subfields and 256 gradations, each subfield is sequentially different at a ratio of 1, 2, 4, 8, 16, 32, 64, and 128. Sets that the gray scale weight value is assigned.

The detailed description will be described with reference to FIGS. 5 and 6.

FIG. 5 is a diagram illustrating in detail a driving process of the first subfield SF1 of FIG. 4.

First, in the reset period R1, a scan pulse is applied to all the scan electrode lines to initialize the discharge cells by making the wall charge states of all the discharge cells uniform.

Next, in the mixed driving period M1, the address discharge step AG1 is performed in the first display electrode line pair group XYG1 during the first group address period PA1. Next, a sustain discharge step S11 is performed for the first display electrode line pair group XYG1 that has been addressed in the first group sustain period PS1. Next, the address discharge step AG2 is performed in the second display electrode line pair group XYG2 during the second group address period PA2.

In the correction sustain period C1, that is, the select sustain period AS1, the sustain discharge step S21 is performed for the second display electrode line pair group XYG2 that has been addressed in the second group address period PA2. Since the gray scale weight value of the first subfield SF1 is 1, the common sustain period does not exist.

6 is a view illustrating in detail a driving process of the fourth subfield SF4 of FIG. 4.

First, in the reset period (R4), the scan pulse is applied to all the scan electrode lines to uniform the wall charge state of all the discharge cells to initialize the discharge cells.

Next, in the mixed driving period M4, the address discharge step AG1 is performed in the first display electrode line pair group XYG1 during the first group address period PA1. Next, a sustain discharge step S11 is performed for the first display electrode line pair group XYG1 that has been addressed in the first group sustain period PS1. Next, the address discharge step AG2 is performed in the second display electrode line pair group XYG2 during the second group address period PA2.

In the selection sustain period AS4 of the correction sustain period C4, the sustain discharge step S21 is performed on the second display electrode line pair group XYG2 that has been addressed in the second group address period PA2.

Next, in the common sustain period CS4 of the correction sustain period C4, seven sustain discharge steps S12 to S18 for the first display electrode line pair group XYG1 to satisfy the gray scale weight value 8 of the fourth subfield. Are provided with seven sustain discharge steps S22 to S28 for the second display electrode line pair group XYG2, respectively. Therefore, the total number of sustain discharges in the fourth subfield is eight times.

Subfields other than the fourth subfield described above are also driven in the manner described above.

FIG. 7 is a timing diagram illustrating a driving process of the fourth subfield SF4 of FIG. 6 as a driving signal.

First, in order to evenly distribute the wall charge states of all the discharge cells, the reset period R4 includes the scan electrode lines of the first display electrode line pair group, that is, the first scan electrode line group YG1 and the second display electrode. The same reset pulse is applied to all scan electrode lines Y1, ..., Yn of the line pair group. Therefore, the rising ramp signal is applied to all of the scan electrode lines Y1,..., And Yn, and the rising maximum voltage is increased by the second voltage Vset. A reset pulse is reached which reaches the third voltage Vset + Vs, and the falling ramp signal is applied at the first voltage Vs to finally reach the fourth voltage Vnf which is the lowest falling voltage. Meanwhile, the fifth voltage Vb, which is a bias voltage, is applied to all the sustain electrode lines X1, ..., Xn of the first to second display electrode line pair groups when the falling ramp signal is applied. The ground voltage Vg is applied to the address electrode lines A1, ..., Am. Meanwhile, the magnitude of the fifth voltage Vb may be the same as the magnitude of the first voltage Vs as shown in FIG. 7.

As the rising ramp function is applied during the reset period R4, weak discharge occurs in the discharge cells, positive wall charges accumulate near the scan electrodes, and negative wall charges near the sustain electrodes and the address electrodes. Will accumulate. As the falling ramp function is applied, weak discharge occurs in the discharge cells, positive wall charges accumulated near the scan electrode are erased, and negative wall charges accumulated near the sustain electrode and the address electrode are erased. Therefore, the wall charge state of all the discharge cells becomes uniform.

Next, in the mixed driving period M4, addressing and sustain discharge are performed simultaneously.

First, in the first group address period PA1, addressing, that is, address discharge, is sequentially performed on the first display electrode line pair group. That is, a sixth voltage Vsch, which is a scan high voltage, is applied to the scan electrode lines Y1, ..., Y of the first display electrode line group, and sequentially has a seventh voltage Vscl that is a scan low voltage. Scan pulses are applied. In this case, a display data signal having an eighth voltage Va, which is an address voltage, is applied to the address electrodes A1, ..., Am, and the sustain electrode lines X1, ..., Xn. ) Is applied with a fifth voltage Vb. The magnitude of the fifth voltage Vb may be the same as the magnitude of the first voltage Vs as shown in the figure. By the display data signal and the scan pulse, an address discharge is performed between the address electrode and the scan electrode in the discharge cell, whereby negative wall charges accumulate near the sustain electrode, and a positive wall near the scan electrode. Charges accumulate. Meanwhile, the ground voltage Vg is applied to the scan electrode lines Y,..., Yn of the second display electrode line group.

Next, in the first group sustain period PS1, one sustain discharge is performed for the first display electrode line pair group. First, the first voltage Vs is applied to all of the scan electrode lines Y1,..., And Yn, and at this time, the ground voltage Vg is applied to all the sustain electrodes X1,..., Xn. do. In the first group address period PA1, the wall voltage due to the positive wall charges accumulated near the scan electrodes of the first display electrode line pair group, the wall voltage due to the negative wall charges accumulated near the sustain electrode, and the scan electrodes The discharge start voltage is reached by the first voltage applied to the sustain discharge, and negative wall charges are accumulated near the scan electrodes, and positive wall charges are accumulated near the sustain electrodes. On the other hand, since wall charges are not accumulated in the vicinity of the scan electrode and the sustain electrode of the second display electrode line pair group, even if the first voltage is applied to the scan electrode, the discharge start voltage does not reach and sustain discharge is not performed. Next, the ground voltage Vg is applied to all the scan electrode lines Y1, ..., Yn, and at this time, the first voltage Vs is applied to all the sustain electrodes X1, ..., Xn. Is approved. The wall voltage caused by the negative wall charges accumulated near the scan electrodes of the first display electrode line pair group, the wall voltage caused by the negative wall charges accumulated near the sustain electrodes, and the first voltage (Vs) applied to the sustain electrodes. When the discharge start voltage is reached, sustain discharge is performed, positive wall charges are accumulated near the scan electrodes, and negative wall charges are accumulated near the sustain electrodes. On the other hand, since wall charges are not accumulated in the vicinity of the scan electrode and the sustain electrode of the second display electrode line pair group, even if the first voltage is applied to the sustain electrode, the discharge start voltage does not reach the sustain discharge. On the other hand, one sustain discharge described in the text includes a sustain discharge performed by applying a first voltage to the scan electrode and a ground voltage to the sustain electrode, a ground voltage to the scan electrode, and a first voltage to the sustain electrode. It means to include a sustain discharge is applied and performed.

Next, in the second group address period PA2, addressing, that is, address discharge, is sequentially performed on the second display electrode line pair group. That is, a sixth voltage Vsch that is a scan high voltage is applied to the scan electrode lines Y,..., And Yn of the second display electrode line group, and the seventh voltage Vscl that is a scan low voltage is sequentially applied. The scanning pulse having is applied. In this case, a display data signal having an eighth voltage Va, which is an address voltage, is applied to the address electrodes A1, ..., Am, and the sustain electrode lines X1, ..., Xn. ) Is applied with a fifth voltage Vb. The magnitude of the fifth voltage Vb may be the same as the magnitude of the first voltage Vs as shown in the figure. By the display data signal and the scan pulse, an address discharge is performed between the address electrode and the scan electrode in the discharge cell, whereby negative wall charges accumulate near the sustain electrode, and a positive wall near the scan electrode. Charges accumulate. Meanwhile, the ground voltage Vg is applied to the scan electrode lines Y1,..., Y of the first display electrode line group.

Next, the correction sustain period C4 consists of the selective sustain period AS4 and the common sustain period CS4. In the selective sustain period AS4, sustain discharge is selectively performed on the first display electrode line pair group and the second display electrode line pair group. One sustain discharge was performed in the first display electrode line pair group in the mixed driving period M4, but no sustain discharge was not performed in the second display electrode line pair group. Therefore, the second display electrode in the selective sustain period AS4. One sustain discharge is performed only in the line pair group, and no sustain discharge is performed in the first display electrode line pair group. To this end, the ground voltage Vg and the first voltage Vs are sequentially applied to all sustain electrode lines X1,..., Xn. While the ground voltage Vg is applied to the sustain electrode lines, the ninth voltage Vm, which is an intermediate voltage, is applied to the scan electrode lines of the first display electrode line pair group, and the ninth voltage Vm of the second display electrode line pair group is applied. The first voltage Vs is applied to the scan electrode lines. That is, in the first display electrode line pair group, the ninth voltage smaller than the first voltage is applied to the scan electrode, so that the discharge start voltage cannot be reached, so that the sustain discharge is not performed. In the second display electrode line pair group, the scan electrode The sustain voltage is applied by applying the first voltage Vs, and negative wall charges are accumulated near the scan electrodes, and positive wall charges are accumulated near the sustain electrodes. Meanwhile, while the first voltage Vs is applied to the sustain electrode lines, the ground voltage Vg is applied to all the scan electrode lines Y1,..., And Yn. In the first display electrode line pair group, the first voltage Vs is applied to the sustain electrode, but the discharge start voltage cannot be reached due to the positive wall charge accumulated near the scan electrode and the negative wall charge accumulated near the sustain electrode. Maintenance discharge is not performed. In the second display electrode line pair group, the sustain discharge is caused by the first voltage Vs applied to the sustain electrode, the wall voltage caused by the negative wall charges accumulated near the scan electrode, and the positive wall charges accumulated near the sustain electrode. Then, positive wall charges are accumulated near the scan electrodes, and negative wall charges are accumulated near the sustain electrodes. As a result, one sustain discharge is performed only in the second display electrode line pair group.

Next, in the common sustain period CS4, sustain discharge is performed in common in the first display electrode line pair group and the second display electrode line pair group. The total number of sustain discharges generated before the common sustain period CS4 is only one time for both the first display electrode line pair group and the second display electrode line pair group. Since the fourth subfield has a gray weighting value of 8, seven sustain discharges are performed in the common sustain period.

In one sustain discharge in the common sustain period, first, the first voltage Vs is applied to all the scan electrode lines Y1, ..., Yn, and the ground is applied to the sustain electrode lines X1, ..., Xn. The voltage Vg is applied, and then the ground voltage Vg is applied to the scan electrode lines Y1, ..., and Yn, and the first voltage Vs is applied to the sustain electrode lines X1, ..., Xn. ) Means maintenance discharge caused by

A description with reference to FIG. 8 is as follows. The first sustain pulse SP1 having the first voltage Vs and then the ground voltage Vg is applied to all the scan electrode lines Y1,..., And Yn. The second sustain pulse SP2 having the ground voltage first and the first voltage Vs is applied to all the sustain electrode lines X1,..., Xn. The ground voltage Vg is applied to the address electrodes.

 In detail, from time t1 to t2, the first sustain pulse SP1 applied to the scan electrode lines Y1, ..., Yn has a rising slope and finally reaches the first voltage Vs. . In this case, the second sustain pulse SP2 applied to the sustain electrode lines X1,..., Xn has a ground voltage Vg. From time t2 to t4, the first sustain pulse SP1 continues to have the first voltage Vs. On the other hand, the second sustain pulse SP2 continues to have the ground voltage Vg from time t2 to t3, has a rising slope from time t3 to t4, and finally reaches the first voltage Vs. As a result, the first sustain pulse SP1 and the second sustain pulse SP2 overlap the first voltage Vs at the time t4. Next, from time t4 to t5, the first sustain pulse SP1 has a falling slope and finally reaches the ground voltage Vg. From time t4 to t7, the second sustain pulse has a first voltage Vs. From time t5 to t6, the first sustain pulse SP1 has the ground voltage Vg. From time t6 to t7, the first sustain pulse SP1 has a rising slope, finally reaching the first voltage Vs, and repeating the above process. From time t7 to t8, the second sustain pulse SP2 has a falling slope, finally reaching the ground voltage, and continuing the ground voltage from time t8 to t9. The rising and falling slopes are typically used for energy charging and recovery.

When the first sustain pulse SP1 has the first voltage Vs, the first positive voltage Vs applied to the scan electrode, the ground voltage Vg applied to the sustain electrode, and the vicinity of the scan electrode are applied. As the sustain discharge is performed due to the wall voltage caused by the accumulated positive wall charges and the wall voltage caused by the negative wall charges accumulated near the sustain electrode, the negative wall charges are accumulated near the scan electrodes and near the sustain electrode. There is a positive wall charge.

Next, when the second sustain pulse SP2 has the first voltage Vs, the first positive voltage Vs applied to the sustain electrode, the ground voltage Vg applied to the scan electrode, and the sustain voltage SPs are held. The sustain discharge is performed due to the wall voltage caused by the positive wall charges accumulated near the electrodes and the wall voltage caused by the negative wall charges accumulated near the scan electrodes. Negative wall charges are accumulated near the electrodes.

 The first sustain pulse SP1 and the second sustain pulse SP2 of FIG. 8 are overlapping waveforms in which sections to which the first voltage Vs is applied overlap each other. The overlapping waveform in the common sustain period CS4 is not limited to overlapping at time t4 as shown in FIG. 8, and may overlap for more time. The longer the overlapping section, the shorter the period between the first sustain pulse SP1 and the second sustain pulse SP2, and the shorter the interval between the sustain discharges. Therefore, the discharge frequency can be increased, and when the discharge frequency is increased, the space charge can be well utilized in sustain discharge, thereby improving the luminous efficiency.

9 illustrates a method of driving address display mixing according to another embodiment of the present invention.

As in the exemplary embodiment of FIG. 9, display electrode line pairs, which are pairs of sustain electrode lines and scan electrode lines, may be grouped into eight display electrode line pair groups. For example, as shown in the drawing, the first display electrode line pair group XYG1 to the eighth display electrode line pair group XYG8 are divided from the top to the bottom of the panel.

Reference numerals SF1 to SF8 denote subfields allocated within the unit frame, XYG1 to XYG8 denote display electrode line pair groups as reference for driving objects, R1 to R8 denote reset times, and M1 to M8 denote respective group addresses. Periods and mixed driving periods having respective group sustain periods which come between the respective group address periods, C1 to C8 indicate correction sustain periods. AS1 to AS8 indicate selected sustain periods provided in each correction sustain period, and CS1 to CS8 indicate common sustain periods provided in each correction sustain period, respectively.

At the reset times R1 to R8, the charge states of all the discharge cells become uniform.

The mixed drive periods M1 to M8 have eight group address periods and seven group sustain periods. Addressing, that is, address discharge, is performed for each display electrode line pair group in each group address period, and sustain discharge is performed for each display electrode line pair group in the group sustain period between the group address periods.

The correction sustain periods C1 to C8 include the selective sustain periods AS1 to AS8 and the common sustain periods CS2 to CS8. In the selection sustain periods AS1 to AS8, the display electrode line pairs are selectively selected so that the number of sustain discharges in each display electrode line pair group is the same by correcting the difference in the number of sustain discharges displayed for each display electrode line pair group in the mixed driving period. Perform maintenance discharge on the group. The common sustain period CS1 to CS8 compares the number of sustain discharges up to the selected sustain period with the number of sustain discharges according to the gray scale weight so that the insufficient number of sustain discharges is performed in common for all display electrode line pair groups. Here, when one frame forming one image is represented by eight subfields and 256 gradations, each subfield is sequentially different at a ratio of 1, 2, 4, 8, 16, 32, 64, and 128. Sets that the gray scale weight value is assigned.

The detailed description will be described with reference to FIGS. 10 and 11.

FIG. 10 is a view illustrating in detail a driving process of the first subfield SF1 of FIG. 9.

First, in the reset period R1, a scan pulse is applied to all the scan electrode lines to initialize the discharge cells by making the wall charge states of all the discharge cells uniform.

Next, in the mixed driving period M1, the address discharge step AG1 is performed in the first display electrode line pair group XYG1 during the first group address period TA1. Next, a sustain discharge step S11 is performed for the first display electrode line pair group XYG1 that has been addressed in the first group sustain period TS1. Next, the address discharge step AG2 is performed in the second display electrode line pair group XYG2 during the second group address period TA2. Next, a sustain discharge step S21 is performed for the second display electrode line pair group XYG2 that has been addressed in the second group sustain period TS2. Next, the address discharge step AG3 is performed in the third display electrode line pair group XYG3 during the third group address period TA3. Next, a sustain discharge step S31 is performed for the third display electrode line pair group XYG3 that has been addressed in the third group sustain period TS3. Next, the address discharge step AG4 is performed in the fourth display electrode line pair group XYG4 during the fourth group address period TA4. Next, a sustain discharge step S41 is performed for the fourth display electrode line pair group XYG4 that has been addressed in the fourth group sustain period TS4. Next, the address discharge step AG5 is performed in the fifth display electrode line pair group XYG5 during the fifth group address period TA5. Next, a sustain discharge step S51 is performed for the fifth display electrode line pair group XYG5 that has been addressed in the fifth group sustain period TS1. Next, the address discharge step AG6 is performed in the sixth display electrode line pair group XYG6 during the sixth group address period TA6. Next, a sustain discharge step S61 is performed for the sixth display electrode line pair group XYG6 that has been addressed in the sixth group sustain period TS6. Next, an address discharge step AG7 is performed in the seventh display electrode line pair group XYG7 during the seventh group address period TA7. Next, a sustain discharge step S71 is performed for the seventh display electrode line pair group XYG7 that has been addressed in the seventh group sustain period TS7. Next, the address discharge step AG8 is performed in the eighth display electrode line pair group XYG8 during the eighth group address period TA8.

In the correction sustain period C1, that is, the selection sustain period AS1, the sustain discharge step S81 is performed for the eighth display electrode line pair group XYG8 that has been addressed in the eighth group address period TA8. Since the gray scale weight value of the first subfield SF1 is 1, the common sustain period does not exist.

FIG. 11 is a view illustrating in detail a driving process of the fourth subfield SF4 of FIG. 9.

First, in the reset period (R4), the scan pulse is applied to all the scan electrode lines to uniform the wall charge state of all the discharge cells to initialize the discharge cells.

Next, in the mixed driving period M4, the address discharge step AG1 is performed in the first display electrode line pair group XYG1 during the first group address period TA1. Next, a sustain discharge step S11 is performed for the first display electrode line pair group XYG1 that has been addressed in the first group sustain period TS1. Next, the address discharge step AG2 is performed in the second display electrode line pair group XYG2 during the second group address period TA2. Next, sustain discharge steps S12 and S21 are performed on the first to second display electrode line pair groups XYG1 to XYG2 that have been addressed in the second group sustain period TS2. Next, the address discharge step AG3 is performed in the third display electrode line pair group XYG3 during the third group address period TA3. Next, sustain discharge steps S13, S22, and S31 are performed on the first to third display electrode line pair groups XYG1 to XYG3 that have been addressed in the third group sustain period TS3. Next, an address discharge step AG4 is performed in the fourth display electrode line pair group XYG4 during the fourth group address period TA4. Next, sustain discharge steps S14, S23, S32, and S41 are performed on the first to fourth display electrode line pair groups XYG1 to XYG4 that have been addressed in the fourth group sustain period TS4. Next, the address discharge step AG5 is performed in the fifth display electrode line pair group XYG5 during the fifth group address period TA5. Next, sustain discharge steps S15, S24, S33, S42, and S51 are performed on the first to fifth display electrode line pair groups XYG1 to XYG5 that have been addressed in the fifth group sustain period TS1. Next, the address discharge step AG6 is performed in the sixth display electrode line pair group XYG6 during the sixth group address period TA6. Next, the sustain discharge steps S16, S25, S34, S43, S52, and S61 are performed on the first to sixth display electrode line pair groups XYG1 to XYG6 that have been addressed in the sixth group sustain period TS6. do. Next, an address discharge step AG7 is performed in the seventh display electrode line pair group XYG7 during the seventh group address period TA7. Next, the sustain discharge steps S17, S26, S35, S44, S53, S62, and S71 for the first to seventh display electrode line pair groups XYG1 to XYG7 which are addressed in the seventh group sustain period TS7. Is performed. Next, the address discharge step AG8 is performed in the eighth display electrode line pair group XYG8 during the eighth group address period TA8.

In the selective sustain period AS4 of the correction sustain period C4, first, the sustain discharge steps S27, S36, S45, S54, S63, S72, and S81 for the second to eighth display electrode line pair groups XYG2 to XYG8. And a period during which the sustain discharge steps S37, S46, S55, S64, S73, and S82 are performed for the third to eighth display electrode line pair groups XYG3 to XYG8. In this case, the sustain discharge step S87 is performed on the eighth display electrode line pair group XYG8. Next, in the common sustain period CS4 of the correction sustain period C4, sustain discharge steps S18, S28, and S38 for all display electrode line pair groups XYG1 to XYG8 to satisfy the gray scale weight value 8 of the fourth subfield. , S48, S58, S68, S78, S88 are provided. Therefore, the total number of sustain discharges in the fourth subfield is eight times.

Subfields other than the fourth subfield described above are also driven in the manner described above.

Meanwhile, the present invention has been described with reference to an embodiment in which the display electrode line pairs of the scan electrode line and the sustain electrode line are grouped into two or four groups to address each group and perform the sustain discharge immediately, but the present invention is not limited thereto. It can be grouped in various numbers so that addressing and maintenance discharge can be performed for each group.

According to the present invention, as the number of groups increases, the waiting time until the sustain discharge is performed after the address discharge according to each group becomes shorter and shorter. In this manner, the standby time is shorter than in the related art, so that wall charges accumulated in the discharge cells after the address discharge become less disturbed than in the prior art, so that accurate sustain discharge can be performed.

According to the present invention as described above, the following effects can be obtained.

First, grouping a pair of scan electrode lines and sustain electrode lines as a pair of display electrode lines, and sequentially performing addressing and sustain discharge for each group until the sustain discharge occurs after addressing than conventional ADS (Address Display Separation). As the standby time of the is reduced, the wall charge inside the discharge cell is less disturbed, so that stable maintenance discharge is performed.

Second, by applying a sustain pulse of overlapping waveforms in which a section in which the sustain discharge voltage, which is the first voltage, is applied to the scan electrode and the sustain electrode is overlapped in the common sustain period, the interval between sustain discharges is shorter and the discharge frequency becomes larger. The discharge efficiency is improved, and the luminance is also improved.

Although the present invention has been described with reference to the embodiments shown in the drawings, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

Claims (5)

For a plasma display panel in which display electrode line pairs, which are pairs of sustain electrode lines and scan electrode lines, are formed side by side, and address electrode lines are formed to be spaced apart from and intersect with the display electrode line pairs, a plurality of subfields are formed in a unit frame. The subfields have a reset period, a mixed drive period, and a correction sustain period, and the display electrode line pairs are driven by grouping two or more display electrode line pair groups. In the driving method of the plasma display panel, The mixing drive period is, Two or more group address periods in which addressing is sequentially performed for each of the display electrode line pair groups; And one or more group sustain periods in which sustain discharge is performed on addressed display electrode line pair groups between the group address periods. The correction holding period is, A selective sustain period in which sustain discharge is selectively performed on the display electrode line pair groups so that the number of sustain discharges in all the display electrode line pair groups coincides with the gray scale weight value of each subfield; And a common sustain period in which sustain discharge is performed in common for all of the display electrode line pair groups. In the selective sustaining period, in order to equalize the number of sustain discharges per group of display electrode line pairs, first, the ground voltage and the first voltage are sequentially applied to all sustain electrode lines, and the sustain discharge does not have to be performed. The ninth voltage and the ground voltage are sequentially applied to the scan electrode lines of the display electrode line pair group, and the first voltage and the ground voltage are applied to the scan electrode lines of the display electrode line pair group to which sustain discharge is further performed. Are applied sequentially, The magnitude of the ninth voltage is smaller than the magnitude of the first voltage, In the common sustain period, the first sustain pulse and the second sustain pulse having the rising slope reaching the first voltage and having the falling slope reaching the ground voltage are respectively the all scan electrode lines and all the sustain electrodes. The lines are alternately applied to each other, and a section having the first voltage in the first sustaining pulse and the second sustaining pulse overlaps in time. The method of claim 1, wherein the reset period, A rising ramp signal is applied to all the scan electrode lines at the first voltage to finally reach a third voltage that is increased by a second voltage, and a falling ramp signal is applied at the first voltage to finally reach a fourth voltage. And a fifth voltage is applied to all of the sustain electrode lines when the falling ramp signal is applied, and a ground voltage is applied to all of the address electrode lines. The method of claim 2, wherein the mixing drive period, In the group address periods, a sixth voltage is applied to scan electrode lines of each display electrode line pair group, and a scan pulse having a seventh voltage is sequentially applied, and an eighth voltage is applied to the address electrode lines in accordance with the scan pulse. A display data signal is applied, and the fifth voltage is applied to all the sustain electrode lines. In the group sustain periods, the first voltage and the ground voltage are sequentially applied to all the scan electrode lines, and the ground voltage and the first voltage are sequentially applied to all the sustain electrode lines. A method of driving a plasma display panel. delete delete

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