KR100738223B1 - Plasma Display Apparatus and Driving Method therof - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display device and a driving method thereof for adjusting a voltage difference between a setdown pulse and a scan pulse supplied to a scan electrode (Y) in an address period. Further, the amount of wall charges lost in such an address period is reduced to stabilize the address discharge and the sustain discharge after the address period.

The plasma display apparatus of the present invention includes one of a plurality of scan electrode groups including a plasma display panel having a plurality of scan electrodes, a driver for supplying a driving voltage to the scan electrodes, and a plurality of scan electrodes each controlled by the driver. The scan electrode group is supplied with a first setdown pulse that gradually falls from the first voltage to a second voltage lower than the first voltage in the reset period, and then maintains the second voltage at the end of the first setdown pulse for a predetermined period. And a driving pulse control unit configured to supply a second setdown pulse, and supply a third setdown pulse gradually descending from the second voltage to a third voltage lower than the second voltage at the end of the second setdown pulse. .

Description

Plasma display device and driving method thereof {Plasma Display Apparatus and Driving Method therof}

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

2 is a diagram illustrating a method of implementing image gradation of a conventional plasma display apparatus.

3 is a view illustrating a driving waveform according to a driving method of a conventional plasma display device.

4 is a view for explaining wall charges distributed in a discharge cell by driving pulses supplied in a reset period and an address period in a conventional drive waveform.

FIG. 5 is a diagram for explaining in detail a scan pulse applied to a scan electrode Y in an address period in a conventional driving waveform; FIG.

6 is a view for explaining the distribution of wall charges in a discharge cell as the time from the end of the set-down to the time when the scan pulse is supplied to the scan electrodes is different for each of the scan electrodes Y ₁ to Y n.

7 is a view for explaining a plasma display device of the present invention.

8 is FIG. 2 is a diagram illustrating scan electrodes formed on a plasma display panel divided into two scan electrode groups in order to explain a method of driving the plasma display apparatus according to the present invention. FIG.

9 is In order to explain the driving method of the plasma display device according to the present invention, the scan electrodes formed on the plasma display panel are divided into four scan electrode groups.

FIG. 10 is a diagram for explaining an example of dividing scan electrodes formed on a plasma display panel into one or more scan electrode groups including different numbers of scan electrodes; FIG.

11A to 11B are views for explaining driving waveforms according to the driving method of the plasma display device of the present invention.

12 is a view for explaining an example in which the voltage of the second setdown pulse Setdown2 is adjusted.

FIG. 13 is a diagram for explaining the relationship between the second voltage V2, the third voltage V3, and the scan voltage (-Vy). FIG.

14A to 14B are diagrams for explaining an example in which the length of the supply period of the second set-down pulse is adjusted according to the scanning order of the scan electrode group.

15 is a diagram for explaining an example of a method of setting a difference in voltage between a setdown pulse and a scan pulse to two or more different values.

Fig. 16 is a view for explaining a change in distribution of wall charges in an address period according to the driving method of the present invention.

FIG. 17 is a view for explaining an example of a method of adjusting a length of a supply period of a second setdown pulse Setdown2 for each scan electrode. FIG.

18 is a view for explaining an example of a method of including a rest period having a predetermined length between scan pulses of each scan electrode group to prevent erroneous discharge between two adjacent scan electrode groups.

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

700: plasma display panel 701: driving pulse control unit

702: data driver 703: scan driver

704: sustain driver 705: drive voltage generator

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display panel, and more particularly, to a plasma display apparatus and a driving method thereof for adjusting a setdown pulse supplied to a scan electrode (Y) in a setdown period.

In general, a plasma display panel is a partition wall formed between a front panel and a rear panel to form one unit cell, and each cell includes neon (Ne), helium (He), or a mixture of neon and helium (Ne + He) and An inert gas containing the same main discharge gas and a small amount of xenon is 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. Such a plasma display panel has a spotlight as a next generation display device because of its thin and light configuration.

1 illustrates a structure of a general plasma display panel.

As shown in FIG. 1, a plasma display panel includes a plurality of sustain electrodes formed by pairing scan electrodes 102 and Y and sustain electrodes 103 and Z on a front substrate 101, which is a display surface on which an image is displayed. The rear panel 110 on which the plurality of address electrodes 113 and X are arranged so as to intersect with the plurality of sustain electrodes on the front panel 100 and the rear substrate 111 forming the rear surface is disposed at a predetermined distance. And parallel to each other.

The front panel 100 includes scan electrodes 102 and Y and sustain electrodes 103 and Z for mutually discharging and maintaining light emission of the discharge cells, that is, transparent electrodes a formed of a transparent ITO material. The scan electrodes 102 and Y and the sustain electrodes 103 and Z provided as a bus electrode b made of a metal material are included in pairs. The scan electrodes 102 and Y and the sustain electrodes 103 and Z are covered by one or more upper dielectric layers 104 which limit the discharge current and insulate the electrode pairs, and discharge conditions on the upper dielectric layer 104 top surface. To facilitate, a protective layer 105 on which magnesium oxide (MgO) is deposited is formed.

The rear panel 110 is arranged such that a plurality of discharge spaces, that is, barrier ribs 112 of a stripe type (or well type) for forming discharge cells are maintained in parallel. In addition, a plurality of address electrodes 113 and X, which perform address discharge to generate vacuum ultraviolet rays, are disposed in parallel with the partition wall 112. On the upper side of the rear panel 110, R, G, and B phosphors 114 which emit visible light for image display during address discharge are coated. A lower dielectric layer 115 is formed between the address electrodes 113 and X and the phosphor 114 to protect the address electrodes 113 and X.

Driving apparatuses for supplying a driving signal to a plurality of electrodes are coupled to the plasma display panel having such a structure to form a plasma display apparatus.

A method of implementing image gradation in the plasma display apparatus having such a structure is shown in FIG. 2.

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

As shown in FIG. 2, in the conventional method of expressing a gray level in a plasma display apparatus, a frame is divided into several subfields having different number of emission times, and each subfield is again configured to reset the discharge cells. RPD), an address period APD for selecting a discharge cell to be discharged, and a sustain period SPD for implementing gray scale according to the number of discharges. For example, when displaying an image with 256 gray levels, a frame period (16.67 ms) corresponding to 1/60 second is divided into eight subfields SF1 to SF8 as shown in FIG. 2, and eight subfields. Each of the SFs SF1 to SF8 is 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 discharge cell to be discharged is caused by the voltage difference between the address electrode X and the transparent electrode which is the scan electrode Y. The sustain period is increased at a rate of 2 ⁿ ( ^where n = 0, 1, 2, 3, 4, 5, 6, 7) in each subfield. In this way, 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.

A driving method of a conventional plasma display apparatus according to the general image gray scale representation method is as follows in FIG. 3.

3 is a view illustrating a driving waveform according to a driving method of a conventional plasma display apparatus.

Referring to FIG. 3, the plasma display apparatus is driven by being divided into a reset period, an address period, and a sustain period as in FIG. 2. In addition, an erase period for erasing a portion of wall charges excessively formed in the discharge cell may be further included and driven.

In the reset period, the rising ramp waveform Ramp-up is applied to all the scan electrodes Y simultaneously. Due to this rising ramp waveform, weak dark discharge occurs in the discharge cell at the full screen. By this setup discharge, positive wall charges are accumulated on the address electrode X and the sustain electrode Z, and negative wall charges are accumulated on the scan electrode Y.

During the set-down period, after the rising ramp waveform is supplied, the ramp ramp starts to fall from the positive voltage lower than the peak voltage of the rising ramp waveform and then falls to the specific voltage level below the ground (GND) level voltage. By generating a weak erase discharge in the cell, the wall charges excessively formed in the discharge cell are sufficiently erased. By this set-down discharge, wall charges such that the address discharge can be stably generated remain uniformly in the discharge cells.

In the address period, a negative scan pulse falling from the scan reference voltage Vsc is sequentially applied to the scan electrode Y, and a positive data pulse is applied to the address electrode X in synchronization with the scan pulse. As the voltage difference between the scan pulse and the data pulse and the wall voltage generated in the reset period are added, address discharge is generated in the discharge cell to which the data pulse is applied. In the discharge 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 Z is supplied with a positive sustain bias voltage Vz so that the voltage difference with the scan electrode Y is reduced during the set down period and the address period so that erroneous discharge with the scan electrode Y does not occur.

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

In addition, in the erase period after the sustain discharge is completed, a voltage of the erase ramp waveform Ramp-ers having a small pulse width and a low voltage level is supplied to the sustain electrode Z to erase the wall charge remaining in the discharge cell of the full screen. You can.

The wall charges distributed in the discharge cells by the driving pulses supplied in the reset period and the address period in the driving waveform will be described with reference to FIG. 4.

4 is a diagram for explaining wall charges distributed in discharge cells by driving pulses supplied in a reset period and an address period in a conventional driving waveform.

4, in the setup period of the reset period, a pulse of a positive rising ramp is supplied to the scan electrode Y, and the sustain electrode Z and the address electrode X are supplied to the scan electrode Y described above. A pulse of a relatively lower voltage is supplied so that negative charges are located on the scan electrode Y, and positive charges are positioned on the sustain electrode Z and the address electrode X as shown in (a). Subsequently, in the set-down period, the pulse of the falling lamp is supplied to the scan electrode Y, and a predetermined bias voltage, preferably the sustain bias voltage Vzb, is supplied and maintained to the sustain electrode Z and the address electrode X. As shown in (b), the wall charges excessively accumulated in the discharge cells are partially erased during the setup period. Through such an erase process, the distribution of wall charges in each discharge cell is even. Subsequently, in the address period, an address discharge is generated as shown in (c) by the scan pulse supplied to the scan electrode Y and the data pulse supplied to the address electrode X.

On the other hand, in the address period, such address discharges are sequentially generated in accordance with the scanning order of the scan electrodes (Y). For example, referring to the case of FIG. 4, the difference in time required to proceed from (b) to (c) is different for each scan electrode (Y). As described above, the application time of the scan pulse for sequentially generating the address discharge is as shown in FIG. 5.

FIG. 5 is a diagram for explaining in detail a scan pulse applied to the scan electrode Y in an address period in a conventional driving waveform.

As shown in FIG. 5, in the conventional driving waveform, scan pulses are sequentially applied to each scan electrode Y according to the arrangement order of the scan electrodes Y ₁ to Yn. For example, as shown in Figure 5, the application of the scan pulse the first to the Y ₁ scan electrode is the fastest arrangement order on the plasma display panel is, and in the following order the Y ₂ scan electrode to the scan pulse of the Y ₁ and then is applied with the scanning pulse.

That is, the scan pulse applied to the Y ₁ scan electrode is supplied after the time t ₁ has elapsed at the end of the set-down of the reset period, and the scan pulse applied to the Y ₂ scan electrode is at the end of the set-down of the reset period. t a time of ₂ as is applied to the past since, Y ₃ scan electrode is applied to since the time t ₃ as in the time of set-down ends of the reset period and, Y _n scan electrodes at the end of the set-down of the reset period, The scan pulse is applied after a time of t _n . As described above, the scan pulses applied to all of the scan electrodes Y ₁ to Y n differ from each other in application time from the time when the set-down of the reset period ends.

Here, as the time from the end of the set-down of the reset period to the time when the scan pulses are supplied to the scan electrodes Y ₁ to Yn becomes longer, the rate at which wall charges decrease in the discharge cells increases. This is a problem caused by combining wall charges in the discharge cells with space charges floating in the space inside the discharge cells.

Accordingly, the later the scanning order is, the lower the amount of wall charges in the discharge cells at the time of the address discharge is generated. This will be described with reference to FIG. 6.

FIG. 6 is a view for explaining the distribution of wall charges in the discharge cells as the time from the end of the set down to the time when the scan pulse is supplied to the scan electrodes is different for each of the scan electrodes Y ₁ to Y n.

Referring to FIG. 6, first, as in the case of the Y ₁ scan electrode of FIG. 5, when the time difference from the time when the reset period is set to the Y ₁ scan electrode to the time when the scan pulse is supplied is relatively short t ₁ , for example, FIG. 6. As shown in (a), the wall charge in the discharge cell is advantageous for the sustain discharge. Here, (a) illustrates that 12 negative charges on the scan electrode Y, 8 positive charges on the sustain electrode Z, and 4 positive charges on the address electrode X are distributed as an example. do.

Next, when the time difference from when the set-down of the reset period ends to the time when the scan pulse is applied to the Y ₂ scan electrode as in the Y ₂ scan electrode of FIG. 5 is relatively longer than t ₁ , t ₂ , for example, FIG. As shown in (b) of FIG. 6, the wall charge in the discharge cell is reduced by a certain amount compared to (a).

In case of Figure 5 the Y ₃ scan electrode and as Y ₃ scan electrode reset period, a set-down the scan pulse from the time is long t ₃ than t ₂ by the time difference and the time above that end of the include, for example, in Fig. 6 As shown in (c), the wall charge in the discharge cell is reduced by a certain amount compared to (a) and (b).

Next, when the time difference from when the set-down of the reset period is completed to the time when the scan pulse is applied to the Yn scan electrode as in the Yn scan electrode of FIG. 5 is t ₄ longer than t ₃ described above, for example, FIG. In the discharge cell, wall charges are reduced by a certain amount compared to (a), (b) and (c).

As the time difference increases from the end of the set-down period to the time when the scan pulse is applied in the reset period, that is, the amount of wall charges in the discharge cells decreases as the scan sequence is delayed, the wall charges formed in the set-down period This is because they are neutralized by combining with the space charges in the discharge cell as time passes.

In this way, each other for each of the scan electrodes (Y ₁ ~ Yn) When, from the end of the set-down scan pulse is the time difference and the time each different from each other are supplied to the intensity of the address discharge, each of the scan electrodes (Y ₁ ~ Yn) in Will be different. For example, as shown in FIG. 6, when a scan pulse is applied to the Y ₁ scan electrode to generate a data pulse and an address discharge applied to the corresponding address electrode X, the wall charge distribution as shown in (a) is Yn. In the case of (a), it is assumed that the scan pulse is applied to the scan electrode to have a data charge applied to the corresponding address electrode X and the wall charge distribution as shown in (b) at the time of generating the address discharge. Strong address discharge occurs, and in (d), a relatively weak address discharge occurs.

Thus, the brightness difference caused by the intensity of the address discharge are different, the intensity of the sustain discharge in the sustain period after the addition is different from one another, each of the scan electrodes (Y ₁ ~ Yn) in accordance with each of the scan electrodes (Y ₁ ~ Yn) There is a possibility.

In addition, in the case of (d), when the time difference from the end of the set-down period of the reset period to the time when the scan pulse is applied increases excessively and the wall charge in the discharge cell is excessively lost, subsequent sustain is performed. There is a problem that no discharge occurs.

In order to solve this problem, the present invention stabilizes the address discharge by adjusting the setdown pulse supplied to the scan electrode (Y) in the set-down period of the reset period, and also makes each address discharge constant for each scan electrode (Y). It is an object of the present invention to provide a plasma display device and a driving method thereof.

The plasma display apparatus of the present invention for achieving the above object is a plasma display panel having a plurality of scan electrodes, a drive unit for supplying a driving voltage to the scan electrode and a plurality of scans each of which comprises at least one scan electrode by controlling such a drive unit One or more scan electrode groups of the electrode group are supplied with a first setdown pulse that gradually decreases from the first voltage to a second voltage lower than the first voltage in the reset period, and then the second voltage is predetermined at the end of the first setdown pulse. And a drive pulse controller for supplying a second setdown pulse that is maintained for a period of time and supplying a third setdown pulse that gradually descends from the second voltage to a third voltage lower than the second voltage at the end of the second setdown pulse. It is characterized by.

In addition, the scanning order of all the scan electrodes included in the scan electrode group including the plurality of scan electrodes among the plurality of scan electrode groups described above is continuous.

The number of scan electrode groups may be two or more and less than or equal to the total number of scan electrodes.

The number of scan electrode groups may be two or more and four or less.

Each scan electrode group may include the same number of scan electrodes.

In addition, at least one scan electrode group of the plurality of scan electrode groups may include a different number of scan electrodes than the other scan electrode groups.

In addition, the slope of the first setdown pulse and the slope of the third setdown pulse is characterized in that the same. On the other hand, the slope of the first setdown pulse and the slope of the third setdown pulse may be different from each other. For example, the absolute value of the slope of the first set down pulse is greater than the absolute value of the slope of the third set down pulse.

In addition, the first voltage may be greater than the voltage of the ground level GND and less than or equal to the sustain voltage Vs.

In addition, the second voltage may be smaller than or equal to the voltage of the ground level GND, and larger than the third voltage.

In addition, the second voltage is characterized in that the voltage of the ground level (GND).

Further, the third voltage may be equal to or greater than the voltage level of the scan pulse supplied to the scan electrode in the address period.

The driving pulse controller may control the length of the supply period of the second set-down pulse to be adjusted according to the scanning order of the corresponding scan electrode group.

The driving pulse controller may be configured such that the length of the supply period of the second set-down pulse is longer as the scan order of the corresponding scan electrode group is delayed.

In addition, the driving pulse controller is configured to supply a second set end pulse of the first set down pulse after the first set down pulse is gradually supplied from the first voltage to the second voltage lower than the first voltage in the reset period of the plurality of scan electrode groups. Among the scan electrode groups, a second setdown pulse for maintaining a voltage for a predetermined period of time is supplied, and a third setdown pulse for gradually descending from the second voltage to a third voltage lower than the second voltage is supplied at the end of the second setdown pulse. The length of the supply period of the second set-down pulse in one or more scan electrode groups may be different from other scan electrode groups.

In addition, the driving pulse controller is configured to supply a second set end pulse of the first set down pulse after the first set down pulse is gradually supplied from the first voltage to the second voltage lower than the first voltage in the reset period of the plurality of scan electrode groups. Each scan electrode is supplied with a second setdown pulse that maintains the voltage for a predetermined period, and at the end of the second setdown pulse a third setdown pulse is gradually supplied from the second voltage to a third voltage lower than the second voltage. In the group, the lengths of the supply periods of the second sustain set-down pulses supplied to all the scan electrodes are equal to each other.

Further, after the first setdown pulse is gradually supplied from the first voltage to the second voltage lower than the first voltage in the reset period among the plurality of scan electrode groups, the second voltage is set at the end of the first setdown pulse. The scan set of scan electrodes is supplied with a second setdown pulse which is held during the first setdown pulse, and at the end of the second setdown pulse is supplied a third setdown pulse which gradually descends from the second voltage to a third voltage lower than the second voltage. And a second scan electrode group whose scanning order is later than that of the first scan electrode group, and in this case, the driving pulse control unit has a length of the supply period of the second set-down pulse in the first scan electrode group. It is characterized in that the shorter than the length of the supply period of the second set down pulse in.

In addition, the driving pulse controller is configured to supply a first setdown pulse that gradually descends from the first voltage to the second voltage lower than the first voltage in the reset period in one scan electrode group having the fastest scanning order among the plurality of scan electrode groups. Thereafter, the supply of the second setdown pulse is omitted so that the third setdown pulse is gradually supplied from the second voltage to the third voltage lower than the second voltage at the end of the first setdown pulse.

Also, the plurality of scan electrodes includes a first scan electrode and a second scan electrode in which the scan order is continuous with the first scan electrode and in which the scan order is later than that of the first scan electrode. A pause period during which a scan pulse is not supplied is included between a time point at which the scan pulse is supplied to the electrode and a time point at which the scan pulse is supplied to the second scan electrode.

In addition, the above-described driving pulse controller is characterized in that the rest period between the first scan electrode and the second scan electrode is partially overlapped with the set-down period in the second scan electrode.

In addition, the driving pulse control unit is characterized in that the length of the rest period is 1 us (microsecond) or more and 100 us (microsecond) or less.

In addition, the driving method of the plasma display device of the present invention for achieving the above object is a driving method of a plasma display device having a plurality of scan electrodes, each of the one or more scan electrodes of the plurality of scan electrode group including at least one scan electrode A second set-down for maintaining the second voltage for a predetermined period at the end of the first set-down pulse after the group is supplied with a first set-down pulse that gradually falls from the first voltage to a second voltage lower than the first voltage in the reset period; A pulse is supplied, and a third setdown pulse is gradually supplied from the second voltage to the third voltage lower than the second voltage at the end of the second setdown pulse.

In addition, the scanning order of all the scan electrodes included in the scan electrode group including the plurality of scan electrodes among the plurality of scan electrode groups may be continuous.

In addition, the slope of the first setdown pulse and the slope of the third setdown pulse is characterized in that the same. On the other hand, the slope of the first setdown pulse and the slope of the third setdown pulse may be different from each other. For example, the absolute value of the slope of the first set down pulse is greater than the absolute value of the slope of the third set down pulse.

In addition, the first voltage may be greater than the voltage of the ground level GND and less than or equal to the sustain voltage Vs.

In addition, the second voltage may be smaller than or equal to the voltage of the ground level GND and greater than the third voltage.

In addition, the second voltage is characterized in that the voltage of the ground level (GND).

Further, the third voltage may be equal to or greater than the voltage level of the scan pulse supplied to the scan electrode in the address period.

Further, after the first setdown pulse is gradually supplied from the first voltage to the second voltage lower than the first voltage in the reset period among the plurality of scan electrode groups, the second voltage is set at the end of the first setdown pulse. At least one scan electrode group of scan electrode groups supplied with a second set down pulse that is held for a period of time and a third set down pulse that is gradually falling from the second voltage to a third voltage lower than the second voltage at the end of the second set down pulse The length of the supply period of the second setdown pulse in the group is different from the other scan electrode groups.

Further, after the first setdown pulse is gradually supplied from the first voltage to the second voltage lower than the first voltage in the reset period among the plurality of scan electrode groups, the second voltage is set at the end of the first setdown pulse. The scan set of scan electrodes is supplied with a second set down pulse which is held during the first set down pulse and a third set down pulse which is gradually lowered from the second voltage to a third voltage lower than the second voltage at the end of the second set down pulse. And a second scan electrode group whose scanning order is later than that of the first scan electrode group, wherein the length of the supply period of the second setdown pulse in the first scan electrode group is equal to the second setdown pulse in the second scan electrode group. It is characterized in that it is shorter than the length of the supply period.

In addition, the plurality of scan electrodes may include a first scan electrode and a second scan electrode in which the scan order is continuous with the first scan electrode and the scan order is later than that of the first scan electrode, and a scan pulse is supplied to the first scan electrode. A pause period in which the scan pulse is not supplied is included between the time point and the time point at which the scan pulse is supplied to the second scan electrode.

In addition, the above-described idle period between the first scan electrode and the second scan electrode may be partially overlapped with the set-down period in the second scan electrode.

In addition, the length of the rest period is characterized in that less than 1us (microseconds) 100us (microseconds).

Hereinafter, a driving apparatus and method of a plasma display panel of the present invention will be described in detail with reference to the accompanying drawings.

7 is a view for explaining a plasma display device of the present invention.

As shown in FIG. 7, in the plasma display device of the present invention, the scan electrode Y, the sustain electrode Z, and the address electrode X are formed, and the scan electrode Y is formed in the reset period, the address period, and the sustain period. The plasma display panel 700 and the plasma display panel 700 may display images formed of frames by a combination of at least one subfield to which a driving pulse is applied to the sustain electrode Z or the address electrode X. A data driver 702 for supplying data to the address electrode X, a scan driver 703 for driving the scan electrode Y, and a sustain driver 704 for driving the sustain electrode Z which is a common electrode. ), A driving pulse controller 701 for controlling the scan driver 703 when the plasma display panel 700 is driven, and a driving voltage required for each of the driving units 702, 703, and 704. A driving voltage generating unit 705 for class.

Here, the above-described plasma display panel 700 is bonded to the front panel (not shown) and the rear panel (not shown) at regular intervals, a plurality of electrodes, for example, a plurality of scan electrodes (Y) is formed, In addition, the address electrode X is formed to intersect the scan electrode Y.

The data driver 702 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 each subfield is supplied by the subfield mapping circuit. The data driver 702 samples and latches data in response to control of a timing controller (not shown), and then supplies the data to the address electrode X.

The scan driver 703 supplies the rising ramp waveform Ramp-up and the falling ramp waveform Ramp-down to the scan electrode Y during the reset period. In addition, the scan driver 703 sequentially supplies the scan pulse Sp of the negative scan voltage (-Vy) to the scan electrode Y during the address period, and applies the sustain pulse SUS to the scan electrode Y during the sustain period. Supplies).

The sustain driver 704 supplies the positive sustain bias voltage Vzb to the sustain electrode Z during the period in which the falling ramp waveform occurs and during the address period or during the address period, and the scan driver 703 during the sustain period. ) Is alternately operated to supply the sustain pulse SUS to the sustain electrode Z.

The drive pulse controller 701 generates a timing control signal for controlling the operation timing and synchronization of the scan driver 703 in the reset period, the address period, and the sustain period, and supplies the timing control signal to the scan driver 703 to scan. The driving unit 703 is controlled. In particular, the driving pulse controller 701 controls the scan driver 703 as described above, so that at least one scan electrode group of the plurality of scan electrode groups each including at least one scan electrode Y is provided with a first voltage in a reset period. Supplying a first setdown pulse that gradually descends from to a second voltage lower than the first voltage, then supplying a second setdown pulse that maintains the second voltage for a predetermined period at the end of the first setdown pulse, and a second setdown At the end of the pulse, a third setdown pulse is gradually supplied from the second voltage to a third voltage lower than the second voltage.

The driving voltage generator 705 generates a setup voltage Vsetup, a scan reference voltage Vsc, a negative scan voltage -Vy, a sustain voltage Vs, a data voltage Vd, and the like. These driving voltages may vary depending on the composition of the discharge gas or the structure of the discharge cell.

Such a function of the plasma display device of the present invention will be more apparent in the following description of the driving method.

The driving method performed by the plasma display apparatus of the present invention having such a structure is as follows.

First, in the driving method of the plasma display apparatus of the present invention, the scan electrode Y formed on the plasma display panel is divided into a plurality of scan electrode groups including one or more scan electrodes Y in the scanning order, and the scan electrodes divided in this way In one or more scan electrode groups of the group, in the reset period, after the first setdown pulse is gradually supplied from the first voltage to the second voltage lower than the first voltage, the second voltage is set at the end of the first setdown pulse. Supplying a second setdown pulse that is held for a while and supplying a third setdown pulse that gradually descends from the second voltage to a third voltage lower than the second voltage at the end of the second setdown pulse. To this end, an example of a method of dividing the scan electrodes Y into a plurality of scan electrode groups will be described first with reference to FIG. 8.

8 is In order to explain the method of driving the plasma display device according to the present invention, the scan electrodes formed on the plasma display panel are divided into two scan electrode groups.

As shown in FIG. 8, the scan electrode Y is divided into an A scan electrode group 801 and a B scan electrode group 802 on the plasma display panel 800.

For example, the A scan electrode group includes scan electrodes from the Ya ₁ scan electrode to the Y (a (n) / 2) scan electrode, and the B holding electrode group is Y (b ((n / 2) +1) The scan electrodes are divided to include scan electrodes from the scan electrodes to the Yb (n) scan electrodes. The reason why the number of scan electrode groups described above is set to two is that driving one plasma display panel into two regions, for example, an upper part and a lower part, is advantageous when considering the cost side of the driving board. .

Here, the scan order of all the scan electrodes Y included in one scan electrode group is continuous. In other words, a predetermined number of scan electrodes Y are bundled and set as a scan electrode group in the scanning order. For example, in the case of FIG. 8, the A scan electrode group includes the scan electrodes from the Ya ₁ scan electrode to the Ya (n / 2) scan electrode, and the B holding electrode group is Yb ((n / 2) +1) scan. Scan electrodes from the electrodes to the Yb (n) scan electrodes, where the scan order is the Ya ₁ scan electrode of the A holding electrode group is the fastest, followed by Ya ₂ , and the scan order is Ya _3. Ya ((n / 2) -1)), Ya (n / 2), Yb ((n / 2) +1) ...... Yb (n-1), Yb (n) to be.

Meanwhile, although the plurality of scan electrodes formed on one plasma display panel is divided into two scan electrode groups in FIG. 8, the number of scan electrode groups may be different from that of FIG. 8. Looking at it as follows.

9 is In order to explain the method of driving the plasma display device according to the present invention, the scan electrodes formed on the plasma display panel are divided into four scan electrode groups.

As shown in FIG. 9, the scan electrode Y is divided into an A scan electrode group, a B scan electrode group, a C scan electrode group, and a D scan electrode group on the plasma display panel 900.

For example, the A scan electrode group 901 includes scan electrodes from a Ya ₁ scan electrode to a Y (a (n) / 4) scan electrode, and the B scan electrode group 902 is Y (b ((n / 4) +1)) scan electrode to Yb ((2n) / 4) scan electrode, in this way the C scan electrode group 903 is Y (c ((2n / 4) +1 Scan electrode to Yc ((3n) / 4) scan electrode, and the D scan electrode group 904 is a Y (d ((3n / 4) +1)) scan electrode to a Yd (n) scan electrode. Separate to include The number of scan electrode groups described above may be set between 2 ≦ N ≦ (n−1) when the number of scan electrodes is at least two to less than the maximum number of scan electrodes, that is, the total number of scan electrodes is n. have.

Here again, the scan order of all the scan electrodes Y included in one scan electrode group is continuous.

In FIG. 9, the number of scan electrodes included in each scan electrode group 901, 902, 903, and 904 is the same, but the number of scan electrodes included in at least one scan electrode group among the plurality of scan electrode groups is determined. It is also possible to set it differently from other scan electrode groups. The number of scan electrode groups can also be adjusted. As described above, an example of changing the number of scan electrodes included in the scan electrode group or adjusting the number of scan electrode groups is as follows.

FIG. 10 is a diagram for describing an example of dividing the scan electrodes formed on the plasma display panel into one or more scan electrode groups including different numbers of scan electrodes.

As shown in FIG. 10, the scan electrode Y is arranged on the plasma display panel 1000 by using the A scan electrode group 1001, the B scan electrode group 1002, the C scan electrode group 1003, and the D scan electrode group ( 1004) and the E scan electrode group 1005.

For example, assuming that the total number of scan electrodes Y is 100 as shown in FIG. 10, such scan electrodes Y, for example, the A scan electrode group 1001 may be formed from the Y1 scan electrode to the Y10 scan electrode. Scan electrodes, the B scan electrode group 1002 includes scan electrodes from the Y11 scan electrode to the Y15 scan electrode, and in this way, the C scan electrode group 1003 includes the Y16 scan electrode, and the D holding electrode. The group 1004 includes the Y17 scan electrode to the Y60 scan electrode, and the E holding electrode group 1005 is divided to include the scan electrodes from the Y61 scan electrode to the Y100 scan electrode. As described above, in one or more of the scan electrode groups, the number of scan electrodes included is different from other scan electrode groups. 10 illustrates a case in which the number of scan electrodes included in each scan electrode group 1001, 1002, 1003, 1004, and 1005 are all different.

In addition, the aforementioned C scan electrode group 1003 is a scan electrode group including only one scan electrode, that is, one Y ₁₆ scan electrode. Unlike the other scan electrode groups, one scan electrode forms one scan electrode group. If it is.

As described above, except in the case where one scan electrode constitutes one scan electrode group, all scan electrodes Y included in the scan electrode group have a continuous scan order. In other words, in the case where one scan electrode group includes a plurality of scan electrodes, for example, Y ₁ , Y ₂ , and Y ₃ scan electrodes, the Y ₁ scan electrode, the Y ₂ scan electrode, and Y ₃ in the scan electrode group The scan electrodes have a continuous scan order.

Here, each scan electrode group includes a different number of scan electrodes. Alternatively, only a predetermined number of scan electrode groups selected from the plurality of scan electrode groups may include a different number of scan electrodes from other scan electrode groups. For example, the A scan electrode group includes 10 scan electrodes, the B scan electrode group includes another 10 scan electrodes, and the following C scan electrode group, D scan electrode group, E scan electrode group, Each of the F scan electrode groups includes 20 scan electrodes.

As described above, a driving method of the plasma display apparatus for dividing the scan electrodes of the plasma display panel into a plurality of scan electrode groups and dividing the scan electrodes into four scan electrode groups as shown in FIG. 9 is as follows.

11A to 11B are views for explaining driving waveforms according to the driving method of the plasma display device of the present invention.

First, referring to FIG. 11A, in the method of driving the plasma display apparatus of the present invention, one or more scan electrode groups of the plurality of scan electrode groups each including one or more scan electrodes Y may be formed from the first voltage V1 in a reset period. The ground level GND at the end of the first setdown pulse Setdown1 is supplied after the first setdown pulse Setdown1 is gradually supplied to the voltage of the ground level GND lower than the first voltage V1. The second setdown pulse Setdown2 is maintained for a predetermined period of time, and at the end of the second setdown pulse Setdown1, a second voltage lower than the voltage of the ground level GND from the voltage of the ground level GND A third setdown pulse Setdown3 is supplied which gradually descends to V2.

For example, when the scan electrodes Ya ₁ to Ybn are divided into two scan electrode groups, that is, the A scan electrode group and the B scan electrode group as shown in FIG. 8, one scan electrode group of the two scan electrode groups For example, in the B scan electrode group, after the first setdown pulse Setdown1 is gradually supplied from the first voltage V1 to the voltage of the ground level GND lower than the first voltage V1 in the reset period, At the end of the first setdown pulse Setdown1, a second setdown pulse Setdown2 for maintaining the voltage of the ground level GND for a predetermined period d1 is supplied, and at the end of the second setdown pulse Setdown1, the ground level is provided. A third setdown pulse Setdown3 that is gradually lowered from the voltage of GND to the second voltage V2 lower than the voltage of the ground level GND is supplied, whereas in the A scan electrode group, the first set in the reset period is provided. With voltage (V1) After the first setdown pulse Setdown1 is gradually supplied down to the voltage of the ground level GND lower than the first voltage V1, the second setdown pulse Setdown2 of the above-described B scan electrode group is supplied. The supply is omitted, and the third setdown pulse Setdown3 is gradually supplied from the voltage of the ground level GND to the second voltage V2 lower than the voltage of the ground level GND.

In this case, it is preferable that the inclination of the first setdown pulse Setdown1 and the inclination of the third setdown pulse Setdown3 are the same. The reason why the inclination of the first setdown pulse Setdown1 is equal to the inclination of the third setdown pulse Setdown3 is that the driving control is easier in consideration of the control of the driving timing in the driving circuit.

On the other hand, it is also possible to set the inclination of the first setdown pulse Setdown1 and the inclination of the third setdown pulse Setdown3 differently. More preferably, the absolute value of the slope of the first setdown pulse Setdown1 described above is greater than the absolute value of the slope of the third setdown pulse Setdown3. That is, the slope of the first setdown pulse Setdown1 is steeper than the slope of the third setdown pulse Setdown3.

In addition, it is preferable that the above-described first voltage V1 is greater than the voltage of the ground level GND and less than or equal to the sustain voltage Vs voltage.

Next, referring to FIG. 11B, a relationship between the second voltage V2 of the third setdown pulse Setdown3 and the scan pulse voltage −Vy is shown.

Referring to FIG. 11B, the second voltage, which is the lower limit of the third setdown pulse Setdown3, has a higher voltage level than the scan voltage −Vy of the scan pulse SP supplied to the scan electrode Y in the address period. As a result, a voltage difference of ΔV occurs between the second voltage and the scan voltage (−Vy). As such, the reason why the voltage level of the second voltage is higher than the voltage level of the scan voltage (−Vy) is due to the scan pulse supplied to the scan electrode Y and the data pulse supplied to the address electrode X in the address period. This is to cause the address discharge to be generated sufficiently strong.

Here, after the first setdown pulse Setdown1 falling to the voltage of the ground level GND in the setdown period of the reset period is supplied to the scan electrode Y, the voltage of the ground level GND is maintained for a predetermined time. When the second setdown pulse Setdown2 is supplied to the scan electrode Y, the setdown discharge generated during setdown is paused while the voltage of the scan electrode Y is at the ground level GND.

Then, the wall charges in the discharge cell proceed to the point before the address discharge occurs in a state where the amount of the erase is less than that of the case where the above-described second setdown pulse Setdown2 is not supplied.

Accordingly, although the scan order of the B scan electrode group is relatively slower than that of the A scan electrode group, the B scan electrode group neutralizes and disappears in combination with the space charge within the period from the set-down period to the time when the address discharge occurs. By reducing the amount of charge, the address discharge in the B scan electrode group is stabilized.

At this time, when there are a plurality of scan electrodes Y included in one scan electrode group, the lengths of the supply periods of the second setdown pulses Setdown2 supplied to all the scan electrodes Y in the setdown period of the reset period are all equal. The same is preferable. For example, the length of the supply period of the above-described second setdown pulse Setdown2 at the scan electrodes included in the B scan electrode group, that is, all the scan electrodes from the Y (b (n / 2) +1) scan electrode to the Ybn scan electrode. Are all the same thing.

Here, in FIGS. 11A to 11B, only the second setdown pulse Setdown2 maintains the voltage of the ground level GND, but the second setdown pulse Setdown2 is different from the ground level GND. It is also possible to maintain a voltage other than the voltage, which will be described with reference to FIG. 12.

12 is a view for explaining an example in which the voltage of the second setdown pulse Setdown2 is adjusted.

12A, unlike FIG. 11A, the voltage of the second setdown pulse Setdown2 is not the voltage of the ground level GND but the voltage of V2.

That is, at least one scan electrode group of the plurality of scan electrode groups each including at least one scan electrode Y, for example, the B scan electrode group of FIG. 12, has the first voltage V1 from the first voltage V1 in the reset period. After the first setdown pulse Setdown1 gradually descends to the second voltage V2 lower than), the second voltage V2 is applied at the end of the first setdown pulse Setdown1 for a predetermined period d2. The second setdown pulse Setdown2 is supplied, and at the end of the second setdown pulse Setdown1, the voltage is gradually increased from the voltage of the second voltage V2 to the third voltage V2 lower than the second voltage V2. The falling third setdown pulse Setdown3 is supplied.

Here, considering the case of FIG. 11A described above with the case of FIG. 12, the voltage of the ground level GND of the second setdown pulse Setdown2 of FIG. 11A described above is the second voltage ( It is equivalent to V2). That is, the second voltage V2 is less than or equal to the voltage of the ground level GND and is greater than the third voltage V3.

The relationship between the second voltage V2 of the second setdown pulse Setdown2 and the third voltage V3 of the third setdown pulse Setdown3 and the scan voltage −Vy will be described with reference to FIG. 13. As follows.

FIG. 13 is a diagram for describing a relationship between the second voltage V2, the third voltage V3, and the scan voltage −Vy.

Referring to FIG. 13, the second voltage V2 of the second setdown pulse Setdown2 described above is greater than the third voltage V3 of the third setdown pulse Setdown3 and smaller than the voltage of the ground level GND. In addition, the second voltage V2 of the second setdown pulse Setdown2 described above is greater than the scan voltage −Vy of the scan pulse SP supplied to the scan electrode Y in the address period. Here, in FIG. 13, the aforementioned third voltage V3 is shown to be larger than the scan voltage −Vy, but preferably, the third voltage V3 is a scan pulse supplied to the scan electrode Y in the address period. It is preferred to be equal to or greater than the voltage level of (-Vy).

As described above, the second voltage V2 of the second setdown pulse Setdown2 is set larger than the third voltage V3 of the third setdown pulse Setdown3 and smaller than the voltage of the ground level GND. When the voltage of the second setdown pulse Setdown2 maintains an excessively high voltage above the ground level GND, the supply period of the third setdown pulse Setdown3 supplied from the end of the second setdown pulse Setdown2 is exceeded. This is because an excessively long length results in a relatively long length of the address period.

As a result, the second voltage V2 of the above-described second setdown pulse Setdown2 is set higher than the third voltage V3 of the third setdown pulse Setdown3 and sufficiently smaller than the voltage of the ground level GND, The length of the supply period of the third setdown pulse Setdown3 supplied at the end of the second setdown pulse Setdown2 is suppressed from being excessively long.

On the other hand, the length of the supply period of the above-described second setdown pulse (Setdown2) pulse is preferably adjusted as the scan order of the scan electrode group is changed, referring to Figures 14a to 14b attached as follows. .

14A to 14B are diagrams for explaining an example in which the length of the supply period of the second set down pulse is adjusted according to the scanning order of the scan electrode group.

14A to 14B, first, a total of 100 scan electrodes are formed on one plasma display panel as shown in FIG. 14A, and these 100 scan electrodes include Y1 scan electrodes to Y50 scan electrodes as shown in (a). Assuming that the A scan electrode group and the B scan electrode group including the Y51 scan electrode to the Y100 scan electrode are divided into two groups, the scan order of the A scan electrode group and the B scan electrode group described above is relatively late. In the group, the length of the supply period of the second setdown pulse Setdown2 supplied to the scan electrode Y, that is, the Y51 scan electrode to the Y100 scan electrode, is d1 in the setdown period of the reset period.

On the other hand, in the case of (b) of FIG. 14A, these 100 scan electrodes include the A scan electrode group including the Y1 scan electrode to the Y90 scan electrode, and the B scan electrode group including the Y91 scan electrode to the Y100 scan electrode. Assuming that it is divided by, in the B scan electrode group in which the scan order of the above-described A scan electrode group and B scan electrode group is relatively late, scan electrodes Y, that is, Y91 scan electrodes to Y100 scans, are set in the set-down period of the reset period. The length of the supply period of the second setdown pulse Setdown2 supplied to the electrode is d2.

14B, the supply period d2 of the second setdown pulse Setdown2 in the B scan electrode group in the case of (b) of FIG. 14A including from the Y91 scan electrode to the Y100 scan electrode as shown in (b). The length is greater than the length of the supply period d1 of the second setdown pulse Setdown2 in the B scan electrode group in the case of (a) of FIG. 14A including from the Y51 scan electrode to the Y100 scan electrode as shown in (a). It is set long.

As a result, the length of the supply period of the above-described second setdown pulse Setdown2 becomes longer as the scan order of the corresponding scan electrode group is delayed.

In more detail, the length of the supply period of the second setdown pulse Setdown2 is determined by the scan electrode having the fastest scan order among the scan electrodes included in the scan electrode group. For example, in FIG. 14A, the scan electrode having the fastest scan order among the scan electrodes included in the B scan electrode group is the Y51 scan electrode, and in the case of (b), the scan electrode included in the B scan electrode group The scan electrode with the fastest scan order is the Y91 scan electrode. At this time, if the length of the supply period of the second setdown pulse Setdown2 in FIG. 14A (b), that is, d2 in the case of (b) in FIG. 14B is applied to the case of FIG. The possibility of erroneous discharge occurring between two adjacent scan electrodes Y from the electrode to the Y90 scan electrode increases. As a result, the length of the supply period of the aforementioned second setdown pulse Setdown2 is determined by the scan electrode having the fastest scan order among the scan electrodes included in the scan electrode group.

On the other hand, here, the length d2 of the supply period of the second setdown pulse Setdown2 in the B scan electrode group in the case of FIG. 14B (b) is the second setdown pulse in the B scan electrode group in the case of FIG. 14B (a). The reason for setting longer than the length d1 of the supply period of (Setdown2) is to make the address discharge more stable by ensuring a sufficient amount of wall charges that contribute to the address discharge during the address discharge in the scan electrode group relatively late in the scan order. to be.

In the above description, the case where the length of the supply period of the second setdown pulse Setdown2 is only one value has been described as an example. Alternatively, the length of the supply period of the second setdown pulse Setdown2 is two or more different values. It is also possible to set to have. This will be described with reference to FIG. 15.

FIG. 15 is a diagram for explaining an example of a method of setting a difference in voltage between a setdown pulse and a scan pulse to two or more different values.

Referring to FIG. 15, the scan electrodes Y formed on one plasma display panel are divided into four scan electrode groups, that is, A scan electrode group, B scan electrode group, C scan electrode group, and D scan electrode group. In the A scan electrode group having the fastest scan order among the four scan electrode groups, the supply of the second setdown pulse Setdown2 is omitted in the setdown period of the reset period, and the B scan whose scan order is later than that of the A scan electrode group described above is omitted. In the electrode group, the length of the supply period of the second setdown pulse Setdown2 supplied to the scan electrode Y in the setdown period of the reset period is set to d1.

In addition, in the C scan electrode group whose scan order is later than the above-described A scan electrode group or B scan electrode group, the length of the supply period of the second setdown pulse Setdown2 supplied to the scan electrode Y in the set down period of the reset period is determined. In the D scan electrode group, which is set to d2 and whose scan order is later than the above-described A scan electrode group, B scan electrode group, and C scan electrode group, the second set-down pulse supplied to the scan electrode Y in the set-down period of the reset period ( The length of the supply period of Setdown2) is set to d3.

Here, the relationship of (d1) <(d2) <(d3) holds.

As described above, in the scan electrode group having a relatively late scan order, if the length of the supply period of the second setdown pulse Setdown2 is longer than that of the sustain electrode group having the relatively quick scan order, the address discharge starts from the end of the setdown. Even if the length of the period up to the time of occurrence becomes longer, the amount of decrease in the wall charge becomes relatively small, whereby the address discharge is stabilized.

In more detail, assuming that scan electrodes are arranged in the same order as in FIG. 9 on the plasma display panel, and that scan pulses SP are sequentially applied according to the arrangement order as shown in FIG. 9, A, B, C scan D group including scan electrodes from Y (d (3n / 4) +1) scan electrode to Ydn scan electrode which has relatively slow scan order among 4 scan electrode groups in the set-down period of reset period The length of the supply period of the second setdown pulse Setdown2 supplied to the scan electrode Y is set to be relatively long d3.

In the C scan electrode group including the scan electrodes from the Yc ((2n / 4) +1) scan electrode to the Yc (3n / 4) scan electrode, which are relatively faster in scanning order than the aforementioned D scan electrode group, the reset is performed. The length of the supply period of the second setdown pulse Setdown2 supplied to the scan electrode Y in the setdown period of the period is set to d2 shorter than d3 described above.

As described above, in the scan electrode group including the scan electrode Y having a relatively late scan order, the length of the supply period of the second setdown pulse Setdown2 supplied to the scan electrode Y in the setdown period of the reset period is relatively determined. The reason why the scan order is longer than that of the fast scan electrode group is as follows.

The fact that the scan order is fast means that the address discharge occurs within a relatively fast time after the reset discharge occurring in the reset period. In other words, the time difference from the time when the set-down of the reset period is completed to the time when the address discharge is generated by the scan pulse SP supplied to the scan electrode Y and the data pulse supplied to the address electrode X is relatively generated. It means short. Immediately after the reset discharge, many priming particles generated by the reset discharge exist in the discharge cell. Accordingly, the priming charges generated by the reset discharge may be sufficiently used in the scan electrode Y of the sustain electrode having the rapid scan order.

On the other hand, the late scan order means that the address discharge occurs after a relatively long time after the reset discharge occurring in the reset period. In other words, the time difference from the time when the set-down of the reset period is completed to the time when the address discharge is generated by the scan pulse SP supplied to the scan electrode and the data pulse supplied to the address electrode is relatively long. Here, the number of the priming charges described above is neutralized by decreasing with the space charges in the discharge cell as time passes. Accordingly, the priming charges generated by the reset discharge may not be sufficiently used in the scan electrode of the sustain electrode in which the address discharge occurs after a relatively long time since the set-down time due to the relatively late scan order. .

Here, after the first setdown pulse Setdown1 falling down to the second voltage V2 is supplied to the scan electrode Y in the setdown period of the reset period, the second voltage maintaining the second voltage V2 for a predetermined time. When the setdown pulse Setdown2 is supplied to the scan electrode Y, the setdown discharge generated during setdown is suspended. Then, the wall charges in the discharge cell proceed to the point before the address discharge occurs in a state where the amount of the erase is less than that of the case where the above-described second setdown pulse Setdown2 is not supplied.

In addition, in the scan electrode group having a relatively late scan order, for example, as shown in FIG. 15, the length of the supply period of the second setdown pulse Setdown2 supplied to the scan electrode Y in the setdown period of the reset period is determined. As d3, when the scan order is longer than d2 of the relatively fast A scan electrode group, the length of the period in which the set-down discharge is suspended is longer than that of the C scan electrode group. Even in the case of the D scan electrode group having a relatively slow scan order, the amount of wall charges participating in the address discharge during the address discharge can be sufficiently secured as in the C scan electrode group.

As a result, as in the case of the D scan electrode group, the amount of wall charges in the discharge cells during the address discharge is relatively high even if the length of the period from the end of the set-down period to the time when the address discharge occurs becomes longer because the scan order is relatively late. As a result, the scanning order becomes approximately the same as that of the fast C scan electrode group.

As a result, the address discharge in the D scan electrode group is stabilized, and the amount of wall charges in the discharge cells in the C scan electrode group and the amount of wall charges in the discharge cells in the D scan electrode group are approximately equal during the address discharge. Allow address discharge to occur evenly across all scan electrodes. This is not limited to the C scan electrode group and the D scan electrode group, but also corresponds to the A scan electrode group and the B scan electrode group in FIG. 15.

In other words, in a scan electrode group having a relatively late scan order, the length of the period during which the set-down discharge is paused in the set-down period is longer than that in a scan electrode group having a relatively quick scan order, thereby providing an address in each scan electrode group. The amount of wall charges during discharge is approximately equal.

As a result, the address discharge is weakened or even the address discharge does not occur due to the lack of the number of priming charges present in the discharge cells.

Accordingly, it is possible to prevent deterioration of image quality when the plasma display device is driven.

The distribution of wall charges in the discharge cell according to the driving method of the plasma display device according to the present invention described above will be described with reference to FIG. 16.

16 is a view for explaining a change in the distribution of wall charges in the address period according to the driving method of the present invention.

Here, FIG. 16 is a view for explaining the change of the wall charge in the address period according to the driving method of the present invention. It is noted that the distribution of the wall charge in the address period does not necessarily follow the distribution tendency of FIG.

Referring to FIG. 16, first, the supply of the second setdown pulse Setdown2 to the scan electrode Y is omitted in the setdown period of the reset period when the scan order is the fastest as in the A scan electrode group of FIG. 15.

That is, in the A scan electrode group having the fastest scan order, the first voltage V1 gradually decreases from the first voltage V1 to the second voltage V2 lower than the first voltage, for example, the ground level GND, in the reset period. After the setdown pulse is supplied, the above-described supply of the second setdown pulse Setdown2 is omitted and the ground level (from the voltage of the second voltage V2, for example, the ground level GND, at the end of the first setdown pulse Setdown1). The third setdown pulse Setdown3 is gradually supplied to the third voltage V3 lower than the voltage of GND.

In the case of such an A scan electrode group, for example, wall charges in the discharge cells are advantageous for sustain discharge as shown in Fig. 16A. For example, in (a), 12 negative charges on the scan electrode Y, 8 positive charges on the sustain electrode Z, and 4 positive charges on the address electrode X are distributed.

Next, as in the B scan electrode group of FIG. 15, when the scan order is later than the aforementioned A scan electrode group, the length of the supply period of the second setdown pulse Setdown2 is set to d1. In this case, for example, the wall charges are distributed in the discharge cells in Fig. 16B and similarly to (A) to favor the sustain discharge.

Next, the length of the supply period of the second setdown pulse Setdown2 is set to d2 longer than d1 when the scanning order is later than the above-described A scan electrode group and B scan electrode group as shown in the C scan electrode group of FIG. 15. . In this case, for example, the wall charges are distributed in the discharge cells in Fig. 16 and the discharge cells similarly to (a) and (b) to favor the sustain discharge.

Next, the length of the supply period of the second setdown pulse Setdown2 is greater than d1 and d2 when the scanning order is later than that of the A scan electrode group, the B scan electrode group, and the C scan electrode group. Set to long d3. In this case, for example, the wall charges are distributed in the discharge cells in Fig. 16 and the discharge cells to favor the sustain discharge similarly to (a), (b) and (c).

As a result, in all cases of FIGS. 16A, 16B, 16C, and 16D, the distribution of wall charges in the discharge cells at the time of the address discharge is equally evenly distributed. do. As a result, the distribution of wall charges in the discharge cells after the address discharge is advantageous for the subsequent sustain discharge.

In the above description, the present invention has been described in the case where the length of the supply period of the second setdown pulse Setdown2 is adjusted for each scan electrode group including a plurality of scan electrodes. Alternatively, however, it is also possible to adjust the length of the supply period of the second setdown pulse Setdown2 described above for each scan electrode, which will be described with reference to FIG. 17.

17 is a view for explaining an example of a method of adjusting the length of the supply period of the second setdown pulse Setdown2 for each scan electrode.

Referring to FIG. 17, the length of the supply period of the second setdown pulse Setdown2 is set to d1 in the Y1 scan electrode.

Further, in the Y2 scan electrode, the length of the supply period of the second setdown pulse Setdown2 is longer than d1 described above, and in the Y3 scan electrode, the length of the supply period of the second setdown pulse Setdown2 is d1 and d2 described above. Is longer than d1.

In this manner, the length of the supply period of the second setdown pulse Setdown2 is different for each scan electrode for each scan electrode.

As described above, the method of adjusting the length of the supply period of the second setdown pulse Setdown2 for each scan electrode is the same as the case where one scan electrode forms one scan electrode group.

As such, when the length of the supply period of the second setdown pulse Setdown2 is adjusted for each scan electrode, it is possible to minimize the difference in wall charges between the scan electrodes in the address period.

In such a driving method of the present invention, there is a possibility that erroneous discharge occurs between two adjacent scan electrodes with a continuous scanning order. In order to prevent this, the supply timing between the scan pulses between the scan electrodes is adjusted.

FIG. 18 is a view for explaining an example of a method of including a rest period having a predetermined length between scan pulses of each sustain electrode group to prevent erroneous discharge between two adjacent scan electrode groups.

Referring to FIG. 18, a plurality of scan electrodes include a first scan electrode Y1, a second scan in which the scan order is continuous with the first scan electrode Y1, and a scan order is slower than that of the first scan electrode Y1. In the case of including the electrode Y2, and the second scan electrode Y2 and the third scan electrode Y3 in which the scan order is continuous and the scan order is later than the second scan electrode Y2, A pause period of a predetermined length W is included between the time point at which the scan pulse is supplied from the first scan electrode Y1 and the time point at which the scan pulse is supplied from the second scan electrode Y2. In this case, the pause period W is a period in which scan pulses are not supplied, and is a difference between application points of scan pulses of two scan electrodes in which the scan order is continuous in time.

As described above, when the scan pulse is not supplied between the scan pulses supplied to the first scan electrode Y1 and the scan pulses supplied to the second scan electrode Y2 as shown in FIG. The rest period preferably overlaps with the set-down period in the second scan electrode Y2 in which the scan order of the first scan electrode Y1 and the second scan electrode Y2 described above is later. For example, the rest period W between the second scan electrode Y2 and the third scan electrode Y3 overlaps a part of the set down period of the third scan electrode Y3 having a relatively late scan order, for example, the d1 period. .

Further, the length of such a rest period is more preferably 1 us (microsecond) or more and 100 us (microsecond) or less.

In this manner, a predetermined time difference is provided between the scan pulses supplied from the two scan electrodes having the continuous scan order, thereby preventing erroneous discharges occurring between two adjacent sustain scan electrodes in the address period.

As such, the technical configuration of the present invention described above can 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 appended claims rather than the foregoing detailed description, and the meaning and scope of the claims are as follows. 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 adjusts the length of the supply period of the second setdown pulse Setdown2 in at least one or more of the scan electrode groups including one or more scan electrodes, thereby reducing the loss of wall charges required during address discharge. By preventing and stabilizing the address discharge, there is an effect of suppressing deterioration of image quality.

Claims (36)

A plasma display panel in which a plurality of scan electrodes are formed; A driver supplying a driving voltage to the scan electrode; And Controlling the driving unit so that at least one scan electrode group of the plurality of scan electrode groups each including at least one scan electrode is gradually lowered from a first voltage to a second voltage lower than the first voltage in a reset period; After supplying a setdown pulse, a second setdown pulse is supplied at the end of the first setdown pulse to maintain the second voltage for a predetermined period, and at the end of the second setdown pulse from the second voltage to the second voltage. A drive pulse controller for supplying a third set down pulse that is gradually lowered to a lower third voltage; Plasma display device comprising a. The method of claim 1, And a scan order of all scan electrodes included in a scan electrode group including a plurality of scan electrodes among the plurality of scan electrode groups is continuous. The method of claim 1, The number of the scan electrode group is two or more, the plasma display device, characterized in that less than the total number of the scan electrode. The method of claim 3, wherein And the number of the scan electrode groups is two or more and four or less. The method of claim 1, And each scan electrode group includes the same number of scan electrodes. The method of claim 1, And at least one scan electrode group of the plurality of scan electrode groups includes a different number of the scan electrodes than other scan electrode groups. The method of claim 1, And the slope of the first setdown pulse and the slope of the third setdown pulse are the same. The method of claim 1, And the slope of the first setdown pulse and the slope of the third setdown pulse are different from each other. The method of claim 8, And an absolute value of the slope of the first set down pulse is greater than an absolute value of the slope of the third set down pulse. The method of claim 1, And the first voltage is greater than the ground level (GND) and less than or equal to the sustain voltage (Vs). The method of claim 1, And the second voltage is less than or equal to the voltage of the ground level GND and greater than the third voltage. The method of claim 11, And the second voltage is a voltage of the ground level (GND). The method of claim 1, And the third voltage is equal to or greater than a voltage level of a scan pulse supplied to the scan electrode in an address period. The method of claim 1, The driving pulse controller And the length of the supply period of the second set-down pulse is adjusted according to the scanning order of the corresponding scan electrode group. The method of claim 14, The driving pulse controller And the length of the supply period of the second set-down pulse is longer as the scan order of the corresponding scan electrode group becomes later. The method of claim 1, The driving pulse controller The second voltage at the end of the first setdown pulse after the first setdown pulse is gradually supplied from the first voltage to the second voltage lower than the first voltage in the reset period of the plurality of scan electrode groups; Is supplied with a second setdown pulse for maintaining a predetermined period, and at the end of the second setdown pulse, a scan electrode is supplied with a third setdown pulse gradually descending from the second voltage to a third voltage lower than the second voltage. And a length of the supply period of the second set-down pulse in one or more scan electrode groups of the group is different from other scan electrode groups. The method of claim 16, The driving pulse controller The second voltage at the end of the first setdown pulse after the first setdown pulse is gradually supplied from the first voltage to the second voltage lower than the first voltage in the reset period of the plurality of scan electrode groups; Is supplied with a second setdown pulse for maintaining a predetermined period of time, and at each end of the second setdown pulse is supplied a third setdown pulse that gradually descends from the second voltage to a third voltage lower than the second voltage. And in the scan electrode group the lengths of the supply periods of the second sustain set-down pulses supplied to all the scan electrodes are the same. The method of claim 16, The second voltage at the end of the first setdown pulse after the first setdown pulse is gradually supplied from the first voltage to the second voltage lower than the first voltage in the reset period of the plurality of scan electrode groups; Is supplied with a second setdown pulse for maintaining a predetermined period, and at the end of the second setdown pulse a third setdown pulse is gradually supplied from the second voltage to a third voltage lower than the second voltage. The group includes a first scan electrode group and a second scan electrode group having a later scanning order than the first scan electrode group. The driving pulse controller And the length of the supply period of the second setdown pulse in the first scan electrode group is shorter than the length of the supply period of the second setdown pulse in the second scan electrode group. The method of claim 1, The driving pulse controller In one scan electrode group having the earliest scan order among the plurality of scan electrode groups, the first setdown pulse is gradually supplied from the first voltage to the second voltage lower than the first voltage in the reset period. The supply of the second setdown pulse is omitted so that the third setdown pulse which is gradually lowered from the second voltage to the third voltage lower than the second voltage is supplied at the end of the first setdown pulse. Device. The method of claim 1, The plurality of scan electrodes includes a first scan electrode and a second scan electrode in which the first scan electrode and the scan order are continuous and the scan order is later than that of the first scan electrode. The driving pulse controller And a pause period during which a scan pulse is not supplied between a time point at which the scan pulse is supplied to the first scan electrode and a time point at which the scan pulse is supplied to the second scan electrode. The method of claim 20, The driving pulse controller And a rest period between the first scan electrode and the second scan electrode to partially overlap with the set-down period in the second scan electrode. The method of claim 20, The driving pulse controller And a length of the pause period is 1 us (microsecond) or more and 100 us (microsecond) or less. In the driving method of a plasma display device having a plurality of scan electrodes, One or more scan electrode groups each including one or more of the scan electrodes are supplied with a first set-down pulse gradually decreasing from a first voltage to a second voltage lower than the first voltage in a reset period; A second setdown pulse is supplied at the end of the first setdown pulse to maintain the second voltage for a predetermined period, and from the second voltage to a third voltage lower than the second voltage at the end of the second setdown pulse. And a third set down pulse which is gradually descended from the plasma display apparatus. The method of claim 23, And a scanning order of all the scan electrodes included in the scan electrode group including the plurality of scan electrodes among the plurality of scan electrode groups is continuous. The method of claim 23, And the slope of the first setdown pulse is the same as the slope of the third setdown pulse. The method of claim 23, And a slope of the first setdown pulse and a slope of the third setdown pulse are different from each other. The method of claim 26, And the absolute value of the slope of the first set down pulse is greater than the absolute value of the slope of the third set down pulse. The method of claim 23, And the first voltage is greater than the ground level (GND) and less than or equal to the sustain voltage (Vs). The method of claim 23, And wherein the second voltage is less than or equal to a voltage at ground level (GND) and greater than the third voltage. The method of claim 29, And the second voltage is a voltage of the ground level GND. The method of claim 23, And wherein the third voltage is equal to or greater than a voltage level of a scan pulse supplied to the scan electrode in an address period. The method of claim 23, The second voltage at the end of the first setdown pulse after the first setdown pulse is gradually supplied from the first voltage to the second voltage lower than the first voltage in the reset period of the plurality of scan electrode groups; Is supplied with a second setdown pulse for maintaining a predetermined period, and at the end of the second setdown pulse, a scan electrode is supplied with a third setdown pulse gradually descending from the second voltage to a third voltage lower than the second voltage. And the length of the supply period of the second setdown pulse in one or more scan electrode groups of the group is different from other scan electrode groups. The method of claim 32, The second voltage at the end of the first setdown pulse after the first setdown pulse is gradually supplied from the first voltage to the second voltage lower than the first voltage in the reset period of the plurality of scan electrode groups; Is supplied with a second setdown pulse for maintaining a predetermined period, and at the end of the second setdown pulse, a scan electrode is supplied with a third setdown pulse gradually descending from the second voltage to a third voltage lower than the second voltage. The group includes a first scan electrode group and a second scan electrode group having a later scanning order than the first scan electrode group. The length of the supply period of the second set down pulse in the first scan electrode group is shorter than the length of the supply period of the second set down pulse in the second scan electrode group. . The method of claim 23, The plurality of scan electrodes includes a first scan electrode and a second scan electrode in which the scan order is continuous with the first scan electrode and in a later scan order than the first scan electrode. And a pause period in which a scan pulse is not supplied between a time point at which the scan pulse is supplied to the first scan electrode and a time point at which the scan pulse is supplied to the second scan electrode. The method of claim 34, wherein And a rest period between the first scan electrode and the second scan electrode is partially overlapped with a set down period in the second scan electrode. The method of claim 34, wherein And the length of the pause period is 1 us (microsecond) or more and 100 us (microsecond) or less.

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