KR20050104639A - Driving method of plasma display panel - Google Patents

Abstract

The present invention relates to a method of driving a plasma display panel.

In the method of driving a plasma display panel according to the present invention, one frame is divided into a plurality of subfields, a plurality of first electrodes are divided into a plurality of groups according to an input image signal, and a first subfield is selected from among a plurality of subfields. Addressing is performed in a first direction with respect to the plurality of groups, and addressing in a second direction opposite to the first direction with respect to the plurality of groups in a second subfield adjacent to a first subfield among a plurality of subfields. Do this. At this time, the weight of the subfield for the group addressed first in any one subfield is equal to or greater than the weight of the subfield for the group addressed later.

In this way, the number of subfields can be increased, and the gray scale expression power can be improved.

Description

Driving method of plasma display panel {DRIVING METHOD OF PLASMA DISPLAY PANEL}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving method of a plasma display panel (PDP), and more particularly to a driving method of a plasma display panel driven by an address-display simultaneous driving method.

Among the flat panel display devices, the plasma display panel has been in the spotlight as a flat panel display device due to the advantages of higher luminance and luminous efficiency and wider viewing angle than other display devices.

A plasma display panel is a flat panel display device that displays characters or images using plasma generated by gas discharge, and tens to millions or more of pixels are arranged in a matrix form according to their size. First, the structure of the plasma display panel will be described with reference to FIGS. 1 and 2.

1 is a partial perspective view of a plasma display panel, and FIG. 2 shows an electrode arrangement diagram of the plasma display panel.

As shown in FIG. 1, the plasma display panel includes two glass substrates 1 and 6 facing each other apart. On the glass substrate 1, the scan electrode 4 and the sustain electrode 5 are formed in pairs and in parallel, and the scan electrode 4 and the sustain electrode 5 are covered with the dielectric layer 2 and the protective film 3. have. A plurality of address electrodes 8 are formed on the glass substrate 6, and the address electrodes 8 are covered with the insulator layer 7. The address electrode 8 and the partition 9 are formed on the insulator layer 7 between the address electrodes 8. In addition, the phosphor 10 is formed on the surface of the insulator layer 7 and on both sides of the partition wall 9. The glass substrates 1 and 6 are disposed to face each other with the discharge space 11 therebetween so that the scan electrode 4, the address electrode 8, the sustain electrode 5, and the address electrode 8 are orthogonal to each other. The discharge space 11 at the intersection of the address electrode 8 and the paired scan electrode 4 and the sustain electrode 5 forms a discharge cell 12.

As shown in FIG. 2, the electrode of the plasma display panel has a matrix structure of n × m. The plurality of address electrodes A ₁ -A _m are arranged in the vertical direction, and the plurality of scan electrodes Y ₁ -Y _n and the storage electrodes X ₁ -X _n are arranged in pairs in the horizontal direction.

In general, an address display separation (ADS) method is used in a plasma display panel.

3 is a view showing an ADS driving method of a general plasma display panel.

Referring to FIG. 3, the plasma display panel performs time division driving by dividing one frame into eight subfields to express gray scales. As described above, each subfield SF1-SF8 includes a reset period (not shown), an address period A1-A8, and a sustain period S1-S8. Is done. The reset period serves to erase the wall charges formed by the previous sustain discharge and to set up the wall charges in order to stably perform the next address discharge. The address periods A1-A8 are periods in which wall charges are accumulated in cells (addressed cells) that are turned on by selecting cells that are turned on and cells that are not turned on in the panel. The sustain periods S1-S8 are periods during which a sustain discharge for actually displaying an image in the addressed cells is performed. The ratio of the light emission periods 1T, 2T, 3T, ..., 128T in each subfield is 1: 2: 4: 8: 16: 32: 64: 128. 3 does not show the reset period.

According to this ADS driving method, the reset period, the address periods A1-A8 and the sustain periods S1-S8 of each subfield SF1-SF8 are separated in time in a unit frame so that the address periods A1-A8 In this step, after the address operation from the first scan electrode to the last scan electrode is completed, the sustain operation in the sustain periods S1-S8 is performed. Therefore, as the number of scan electrode lines increases, the time period occupied by the address period for each subfield becomes longer, and the sustain period becomes shorter, resulting in a decrease in the brightness of the screen. Significant time difference occurs until there is a problem that the sustain discharge operation may become unstable.

SUMMARY OF THE INVENTION The present invention has been made in an effort to solve the above problems, and a method of driving a plasma display panel in which a sustain discharge can be stably generated by minimizing a time difference occurring until a sustain discharge occurs in an addressed cell. It is to provide.

In order to achieve the above object, according to an aspect of the present invention, a frame including a plurality of first electrodes, second electrodes and address electrodes, and displayed on the plasma display panel corresponding to an image signal input from the outside There is provided a driving method of a plasma display panel for dividing a into a plurality of subfields and combining the weights of the subfields to display gray levels. The driving method divides the plurality of first electrodes into a plurality of groups including a first group and a second group, and includes a plurality of first electrodes included in the first group in an address period of a first subfield among the plurality of subfields. Performing addressing on the first electrode of the second electrode; performing sustain discharge for a predetermined time on the discharge cells addressed in the first group; performing addressing on the plurality of first electrodes included in the second group Performing sustain discharge for a predetermined time with respect to the discharge cells addressed in the first group and the second group, and in the sustain period, selectively for the discharge cells addressed in the first group and the second group And performing additional sustain discharge, wherein the weight of the first subfield for the first group is different from the weight of the first subfield for the second group. . In this case, the weight of the first subfield for the first group may be greater than the weight of the first subfield for the second group.

And addressing a plurality of first electrodes included in the second group in an address period of a second subfield adjacent to the first subfield, and for a predetermined time with respect to the discharge cells addressed in the second group. Performing sustain discharge, performing addressing on a plurality of first electrodes included in the first group, and performing sustain discharge for a predetermined time with respect to the discharge cells addressed in the first group and the second group. And in the sustaining period, selectively performing additional sustain discharge on the discharge cells addressed in the first group and the second group, the weight of the second subfield for the second group and The weights of the second subfields for the first group are changed. In this case, the weight of the second subfield for the second group may be greater than the weight of the second subfield for the first group.

According to another aspect of the present invention, there is provided a method of driving a plasma display panel, wherein the plurality of first electrodes are divided into a plurality of groups, and a first subfield of the plurality of subfields is disposed in a first direction with respect to the plurality of groups. Performing addressing, and performing addressing to the plurality of groups in a second direction opposite to the first direction in a second subfield adjacent to a first subfield among the plurality of subfields; The weight of the group addressed first in any one subfield is equal to or greater than the weight of the group addressed later.

A method of driving a plasma display panel according to an exemplary embodiment of the present invention will now be described in detail with reference to the accompanying drawings.

First, with reference to the accompanying drawings will be described in detail to be easily carried out by those of ordinary skill in the art with respect to embodiments of the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In describing the present invention, when it is determined that the detailed description of the related known function or configuration may unnecessarily obscure the gist of the present invention, the detailed description is omitted. In addition, the same code | symbol is attached | subjected about the similar part throughout the specification.

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

As shown in FIG. 4, the plasma display panel according to an exemplary embodiment of the present invention includes a plasma panel 100, a controller 200, an address driver 300, a sustain electrode driver 400, and a scan electrode driver 500. do.

The plasma panel 100 includes a plurality of address electrodes A1 to Am arranged in the column direction, a plurality of sustain electrodes X1 to Xn arranged in the row direction, and scan electrodes Y1 to Yn.

The controller 200 receives an image signal from the outside and outputs an address driving control signal, a sustain electrode X driving control signal, and a scan electrode Y driving control signal. The controller 200 divides and drives one frame into a plurality of subfields, and each subfield is represented by a reset period, an address period, and a sustain period.

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

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

The scan electrode driver 500 receives the scan electrode Y driving control signal from the controller 200 and applies a driving voltage to the scan electrode Y. In addition, the scan electrode driver 500 according to an exemplary embodiment of the present invention drives a plurality of scan electrodes into a plurality of groups, and includes a plurality of driving circuits for driving the scan electrodes belonging to each group.

Hereinafter, a controller according to an exemplary embodiment of the present invention will be described in detail with reference to FIG. 5. FIG. 5 is a block diagram illustrating a controller in a plasma display panel according to an exemplary embodiment of the present invention.

As shown in FIG. 5, the controller 200 includes a frame memory 210, a subfield generator 220, a timing controller 230, and a sustain pulse number generator 240.

The frame memory 210 generates and stores image data of an image signal input from the outside.

The subfield generator 220 generates subfield data from the image data stored in the frame memory 210 and transmits the subfield data to the address driver 300. That is, the subfield generator 220 divides the image data stored in the frame memory 210 into a plurality of subfields for one frame and outputs the subfield data to each subfield in order to display the gray scale in the panel. At this time, the subfield generator 220 changes the advancing direction of neighboring subfields. For example, if a subfield is addressed from the top to the bottom, the neighboring subfields are addressed from the bottom to the top.

The sustain pulse number generator 240 outputs the sustain pulse number according to a weight to be displayed in each group of each subfield based on the subfields generated by the subfield generator 220. In this case, the plurality of groups divided in one subfield may have different weights, and the weights to be displayed in each group of each subfield have a first direction with respect to the plurality of scan electrodes included in the plurality of groups. When addressing from (up to down), the weight of the subfield for the group located above is greater than the weight of the subfield for the group located below.

The timing controller 230 generates various timing signals necessary for the operation of the subfield generator 220 and the sustain pulse number generator 240.

Hereinafter, a driving method of the plasma display panel according to an exemplary embodiment of the present invention will be described in detail with reference to FIGS. 6 to 9.

6 is a diagram illustrating a method of driving a plasma display panel according to a first embodiment of the present invention.

As shown in Fig. 6, one frame is driven by dividing into a plurality of subfields, and each subfield includes a reset period, an address period T1, a common sustain period T2, and a luminance correction period T3. A plurality of groups are divided based on the scan electrode lines Y1-Yn, and each group performs ADS driving.

The address period T1 includes an address period A and a sustain period S. FIG. The address period T1 is a period in which all of the pixels of the panel are addressed and sustain discharge is performed in the middle of the address so that the address period A and the sustain period S are mixed in time, and the common sustain period T2. Is a period in which sustain discharge is commonly performed for a certain period of time for all the pixels. The luminance correction period T3 is a period in which additional sustain discharge is selectively performed to correct all luminance of the pixels of the panel so that the gradations of all the pixels of the panel match each other.

In the reset period, reset discharge is performed by simultaneously performing a reset operation on all the scan electrode lines. Meanwhile, in the reset period, the reset operation may be separately performed for each group by providing a reset period before the address period A without performing all groups simultaneously.

In the address period T1, an address operation is performed on each scan electrode in the first group G1, and then a sustain discharge pulse is applied to the scan electrodes of the group G1 to cause a sustain discharge. Then, an address operation is performed on each scan electrode in the second group G2, and then a sustain discharge pulse is applied to the scan electrodes of the group G2 to generate a sustain discharge. In this way, sustain discharge is caused to the scan electrodes of the last group Gn. In addition, while the sustain discharge is performed with respect to any one group of pixels, the sustain discharge is performed with respect to the other group of pixels that are previously addressed.

Subsequently, in the common sustain period T2, a sustain discharge pulse is commonly applied to the scan electrodes Y in all groups to cause sustain discharge.

In the luminance correction period T3, since the length of the sustain period for each group is different in the address period T1, in order to ensure that all the pixels have the same luminance, an additional sustain period is selectively provided for each group to perform sustain discharge. The luminance of the pixels of each group is corrected. Specifically, the luminance of the pixels of the first group G1 is determined by the sum of the weights of the respective weights in the sustain period S of the address period T1 and the weight of the common sustain period T2. The pixels of the first group G1 have the highest luminance at the beginning of the luminance correction period T3. In order to ensure that the pixels of the other group also have the luminance of the pixels of the first group G1, the sustain discharge is additionally performed for a sustain period. This allows all the pixels in the panel to produce the same brightness.

When the additional sustain discharge in the luminance correction period T3 ends, the reset period of the next subfield starts again.

In the driving method as in the first embodiment of the present invention, since the sustain discharge is immediately generated in the addressed pixel, stable sustain discharge is performed. However, compared with the conventional drive waveform, the sustain period in which the address period T2 is inserted in each group is performed. There is a problem that increases by (S). Hereinafter, an embodiment that can solve this problem will be described in detail with reference to FIGS. 7 to 8. In the following, a plurality of scan electrodes are driven by dividing into four groups, and one frame is divided into four subfields to express 16 gray levels.

7A and 7B illustrate a method of driving a plasma display panel according to a second embodiment of the present invention. FIG. 7A illustrates a first subfield and a second subfield, and FIG. 7B illustrates a third subfield and a second subfield. 4 shows a subfield.

As shown in Figs. 7A and 7B, in each subfield, there is a sustain period having different weights for each group, and 16 gray scales are displayed as the sum of the respective weights in the subfields having different weights. If the address direction is from the top to the bottom in the address period of one subfield, the address is performed from the bottom to the top in the address period of the subfield neighboring the subfield.

Specifically, one frame is driven by dividing into four subfields, and each subfield includes a reset period, an address period, and a sustain period.

The reset period serves to erase the wall charges formed by the previous sustain discharge and to set up the wall charges in order to stably perform the next address discharge. The address period is a period in which a wall discharge is accumulated in a cell (addressed cell) that is turned on by selecting a cell that is turned on and a cell that is not turned on, and a sustain discharge is performed in the cell turned on. The sustain period is a period in which sustain discharge is performed to actually display an image in the addressed cells. According to the exemplary embodiment of the present invention, the address period is a period in which the address period and the sustain period are mixed in time, and immediately after the address operation is performed on each scan electrode, a sustain discharge pulse is applied to the scan electrode.

The plasma display panel is connected with a scan / hold driving circuit for applying a driving voltage to the scan electrode Y and the sustain electrode Y and an address driving circuit for applying a driving voltage to the address electrode A in each period. Achieves the display device.

First, referring to FIG. 7A, in the reset period of the first subfield, reset discharge is performed by simultaneously performing the reset operation on the scan electrodes of all groups.

In the address period of the first subfield, the scan period is sequentially applied from the first scan electrode Y11 of the first group G1 to the last scan line Y1m to perform the address period AG1. When all of the address operations for the cells of the first group are completed, the sustain period S11 is performed to sustain and discharge these addressed cells by a predetermined number of sustain pulses. When the first sustain period S11 of the first group ends, the address period AG2 for the cells of the second group is performed. When the address period AG2 of the second group G2 ends, that is, when all the address operations for the scan electrodes belonging to the second group are completed, the first holding period S21 for the second group G2 is completed. Is performed. At this time, the second holding period S12 is simultaneously performed even in the first group G1 in which the address period has already been performed according to the gradation to be displayed in the first group G1. This process is repeated to perform address discharge in the address period of the fourth group G4, and then sustain discharge is performed in the sustain period.

In the sustain period of the first subfield, sustain discharge is additionally performed according to the gradation to be displayed by each group. That is, according to the address direction (G1? G2? G3? G4), the subfield of the first group G1 displays the weight 8, the subfield of the second group G2 indicates the weight 4, and the third group G3 The subfield of) denotes the weight 2 and the subfield of the fourth group G4 denotes the weight 1. Therefore, in addition to the sustain discharge performed in the address period, the first group G1 and the second group G2 additionally perform sustain discharge to display grayscales to be displayed in each group.

In this manner, when the first subfield is completed, the second subfield is started.

In the reset period of the second subfield, the operation is performed in the same manner as the reset period of the first subfield. → address G3? G2? G1). The weight is applied in the same manner as the first subfield according to the address progress direction (G4? G3? G2? G1). At this time, a partly irregular weight may be applied according to the address direction in the address period.

In the sustain period of the second subfield, similarly to the sustain period of the first subfield, sustain discharge is additionally performed according to the gradation to be displayed by each group. In this case, in the second subfield, since the address progress direction (G4 → G3 → G2 → G1) starts from the fourth group G4, the subfield of the fourth group G4 displays the weight 8 and the third group G3. ) Indicates a weight of 4. The subfield of the second group G2 displays the weight 2, and the subfield of the first group G1 displays the weight 1.

Referring to FIG. 7B, after performing the first subfield and the second subfield in the third subfield and the fourth subfield, the display gray level of each group is corrected. After the reset period is completed in the third subfield, in the address period of the third subfield, an address is performed from the top to the bottom in the reverse order of the address progress order of the second subfield (G4-> G3-> G2-> G1). In the fourth subfield, addresses from bottom to top are performed in the reverse order of address progress of the third subfield. In the first group of the third subfield, the total weight of the first subfield and the second subfield is 9, so that the remaining weights of the third subfield and the fourth subfield should be displayed in order to display 16 gray levels. . That is, in order to further display weights 6 in the third and fourth subfields of the first group, weights 4 are displayed in descending order in the order of address progress in the third subfield, and weights 2 are displayed in the fourth subfield. do. In some cases, the opposite may be displayed.

 In addition, since a total weight of 6 is displayed in the first subfield and the second subfield of the second group, a weight of 10 should be additionally displayed to display 16 gray levels. By properly distributing this, the weight 8 is displayed in the third subfield and the weight 1 is displayed in the fourth subfield. In some cases, the opposite may be displayed.

Similarly, in the third subfield and the fourth subfield of the third group and the fourth group, the third group and the fourth group are appropriately distributed according to the gradation to be displayed.

That is, in the first embodiment of the present invention, when the plurality of scan electrodes is divided into n groups, the n groups are addressed in the first order (up-down) and the next subfield is addressed in the opposite order to the first order (down). →). When addressing n groups in a first order (up-down), subfields having a lower weight are arranged in n groups according to the addressing order for n groups. In this way, the time for displaying the gradation in one subfield can be reduced than in FIG.

In this way, the time for displaying the gradation in one subfield can be reduced than in FIG. Therefore, the number of subfields can be increased, and the gray scale expression power can be improved.

In the first embodiment of the present invention, in order to display 16 grayscale images, each group of subfields has different weights, and the weights of each group are in descending order according to the address progress direction. have. Hereinafter, a driving method of the plasma display panel according to the second embodiment of the present invention will be described in detail with reference to FIGS. 8A and 8B.

8A and 8B illustrate a method of driving a plasma display panel according to a second embodiment of the present invention. FIG. 8A illustrates a first subfield and a second subfield, and FIG. 8B illustrates a third subfield and a second subfield. 4 shows a subfield.

As shown in Figs. 8A and 8B, as in the first embodiment, the address progress order in the address period of one subfield is made to be the reverse order of the address progress in the address period of neighboring subfields, and the address progress order As a result, the weights of the sustain discharges in the sustain period of each group are in descending order.

Referring to FIG. 8A, the subfields of the first group and the second group display a weight of 8, and the subfields of the third group and the fourth group of display a weight of 4. In the second subfield, the subfields of the first group and the second group display the weight 4 and the subfields of the third group and the fourth group display the weight 8 in the reverse order of the first subfield.

Referring to FIG. 8B, since a total weight of 12 is displayed in the first subfield and the second subfield in the third subfield, a weight of 3 is further displayed in the third and fourth subfields to display 16 gray levels. . Since the order of address progression of the third subfield is from the top to the bottom, and the order of address progression of the fourth subfield is the opposite, the higher weight is displayed on the third subfield. Accordingly, the weight 2 is displayed in the third subfield of the first group G1 and the weight 1 is displayed in the fourth subfield. In contrast to the first group, the second group G2 displays the weight 1 in the third subfield of the third group G3 and displays the weight 2 in the fourth subfield of the fourth group G4. In some cases, the opposite may be displayed.

That is, in the second embodiment of the present invention, when the plurality of scan electrodes are divided into 2n groups, the 2n groups are addressed in the first order (up-down) and the next subfield is addressed in the opposite order to the first order (below). →). When addressing in the first order (up-down) for 2n groups, place high-weight subfields in the n groups located above and low-weight subfields in the n groups located below. do. In this way, the time for displaying the gradation in one subfield can be reduced than in FIG.

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

As described above, according to the present invention, the operation time of one subfield can be reduced, thereby increasing the number of subfields. Therefore, there is an effect that can improve the gray scale expression.

1 is a partial perspective view of a typical plasma display panel.

2 is an electrode array diagram of a general plasma display panel.

3 is a view illustrating an ADS driving method of a general plasma display panel.

4 is a schematic conceptual diagram of a plasma display panel according to an exemplary embodiment of the present invention.

5 is a configuration diagram of the controller shown in FIG. 4.

6 is a diagram illustrating a method of driving a plasma display panel according to a first embodiment of the present invention.

7A and 7B illustrate a driving method of a plasma display panel according to a second embodiment of the present invention.

8A and 8B illustrate a driving method of a plasma display panel according to a third exemplary embodiment of the present invention.

Claims (5)

A plurality of first electrodes, a second electrode, and an address electrode are included, and one frame displayed on the plasma display panel is divided into a plurality of subfields in response to an image signal input from the outside, and the weights of the respective subfields are combined. In the method of driving a plasma display panel, Dividing the plurality of first electrodes into a plurality of groups including a first group and a second group, In the address period of the first subfield of the plurality of subfields, Performing addressing on the plurality of first electrodes included in the first group; Performing sustain discharge for a predetermined time on the discharge cells addressed in the first group; Performing addressing on the plurality of first electrodes included in the second group; Performing sustain discharge for a predetermined time on the discharge cells addressed in the first group and the second group, and In the sustaining period, selectively performing a further sustain discharge on the discharge cells addressed in the first group and the second group Including; And a weight of the first subfield for the first group and a weight of the first subfield for the second group. The method of claim 1, And a weight of the first subfield for the first group is greater than a weight of the first subfield for the second group. The method according to claim 1 or 2, In the address period of the second subfield adjacent to the first subfield, Performing addressing on the plurality of first electrodes included in the second group; Performing sustain discharge for a predetermined time on the discharge cells addressed in the second group; Performing addressing on the plurality of first electrodes included in the first group; Performing sustain discharge for a predetermined time on the discharge cells addressed in the first group and the second group, and In the sustaining period, selectively performing a further sustain discharge on the discharge cells addressed in the first group and the second group Including; And a weight of the second subfield with respect to the second group and a weight of the second subfield with respect to the first group. The method of claim 3, wherein And a weight of the second subfield for the second group is greater than a weight of the second subfield for the first group. A plurality of first electrodes, a second electrode, and an address electrode are included, and one frame displayed on the plasma display panel is divided into a plurality of subfields in response to an image signal input from the outside, and the weights of the respective subfields are combined. In the method of driving a plasma display panel, Dividing the plurality of first electrodes into a plurality of groups, Performing addressing in a first direction on the plurality of groups in a first subfield of the plurality of subfields, and Performing addressing in the second direction opposite to the first direction with respect to the plurality of groups in a second subfield adjacent to a first subfield among the plurality of subfields. Including; And a weight of a group addressed first in any one subfield is equal to or greater than a weight of a group addressed later.