KR100774967B1 - Plasma display apparatus - Google Patents

Abstract

A plasma display apparatus is provided to suppress image sticking by adjusting a part of image data in an image sticking mode. A plasma display apparatus includes a plasma display panel(100) and a driver(110). The plasma display panel displays images by using a plasma discharge. The driver divides the images, which are displayed in the plasma display panel, into plural regions, selects at least one of the plural regions, and varies image data in the selected regions. The driver adjusts the image data by turning off image data in the selected regions. The driver adjusts the image data by turning off turned on image data and by turning on turned off image data among the image data in the selected regions.

Description

Plasma Display Apparatus {Plasma Display Apparatus}

BRIEF DESCRIPTION OF DRAWINGS Fig. 1 is a diagram for explaining the configuration of a plasma display device of the present invention.

2A to 2B are views for explaining an example of the structure of a plasma display panel included in the plasma display device of the present invention.

FIG. 3 is a diagram for explaining a frame for implementing grayscale of an image in the plasma display device of the present invention; FIG.

4 is a view for explaining an example of the operation of the plasma display device of the present invention;

FIG. 5 is a diagram for describing a fixation afterimage mode setting in consideration of the duration of the same image. FIG.

FIG. 6 is a diagram for explaining a fixed afterimage mode setting in consideration of an average power level. FIG.

FIG. 7 is a view for explaining an example of a method of changing image data in a fixed afterimage mode. FIG.

8 is a view for explaining a specific embodiment of the method of FIG.

9A to 9B are diagrams for explaining an example of a method for setting a region.

FIG. 10 is a diagram for explaining a method of adjusting the number of sustain signals per gray level in a fixed afterimage mode. FIG.

11 is a diagram for explaining a procedure of changing video data.

12 is a diagram for explaining an example of a method of simultaneously changing video data of a plurality of regions.

FIG. 13 is a view for explaining another example of a method of changing image data in a fixed afterimage mode. FIG.

14 is a view for explaining a specific embodiment of the method of FIG.

15 is a view for explaining another example of a method of changing image data in a fixed image retention mode.

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

100: plasma display panel 110: driver

The present invention relates to a plasma display device (Plasma Display Apparatus).

The plasma display apparatus includes a plasma display panel having electrodes formed thereon, and a driving unit supplying predetermined driving signals to the electrodes of the plasma display panel.

In a plasma display panel, a phosphor layer is formed in a discharge cell divided by a partition wall, and a plurality of electrodes, for example, a scan electrode Y, a sustain electrode Z, and an address electrode X are formed. Is formed.

The driver supplies a driving signal to the discharge cell through the electrode.

Then, the discharge is generated by the driving voltage supplied in the discharge cell. Here, when discharged by the driving voltage in the discharge cell, the discharge gas filled in the discharge cell generates vacuum ultraviolet rays, and the vacuum ultraviolet light emits the phosphor formed in the discharge cell to emit visible light. Generate. The visible light displays an image on the screen of the plasma display panel.

Here, the discharges generated in the discharge cells of the plasma display panel include reset discharges, address discharges, sustain discharges, and the like.

The reset discharge is a discharge for initializing all discharge cells, the address discharge is a discharge for selecting a discharge cell in which the sustain discharge, which is the display discharge, is to be generated, and the sustain discharge is a display discharge for displaying an image on the screen.

The address discharge is generated by the data signal applied to the address electrode X and the scan signal applied to the scan electrode Y.

The plasma display apparatus implements a predetermined image on the screen by using such a discharge, and there is a problem in that an afterimage occurs on the screen of the plasma display apparatus when substantially the same image is continuously implemented on the screen.

For example, when an image of a specific pattern is continuously implemented on the screen for a predetermined time or more, the same type of discharge is continuously generated in the discharge cells corresponding to the image of the specific pattern. As a result, the type of discharge is fixed in the discharge cells corresponding to the image of the specific pattern.

As a result, even when the image is switched to an image other than the image of a specific pattern, an afterimage occurs such that the specific pattern image remains dim on the screen.

In order to solve the above problems, the plasma display apparatus of the present invention prevents the afterimages from being discharged in the discharge cells when the image of a specific pattern is continuously implemented on the screen for a predetermined time or more. It is an object of the present invention to provide an improved plasma display device.

In the plasma display apparatus of the present invention for achieving the above object and in the fixed display mode and the plasma display panel for displaying an image using the plasma discharge, the image displayed on the plasma display panel is divided into a plurality of areas, the plurality of areas It is preferable to include a driving unit for selecting one or more and to change the image data of the selected area.

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The driving unit may change the image data by turning off the image data of the selected area.

The driving unit may change the image data by turning on an off state and turning off an on state of the image data of the selected region.

The driver may change the image data by adjusting a gain of the image data of the selected area.

In addition, at least one of the plurality of regions is characterized in that the discharge cell unit.

In addition, at least one of the plurality of regions may be formed in a pixel unit including a plurality of discharge cells.

In addition, the fixed afterimage mode is characterized in that the substantially same image is displayed on the plasma display panel for a predetermined time or more.

In addition, the fixed afterimage mode is characterized in that the image of the same average power level (APL) is displayed on the plasma display panel for a predetermined time or more.

The predetermined time may be 1 minute or more and 10 minutes or less.

Hereinafter, a plasma display device of the present invention will be described in detail with reference to the accompanying drawings.

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

Referring to FIG. 1, the plasma display apparatus of the present invention includes a plasma display panel 100 and a driver 110.

Here, the plasma display panel 100 displays an image by using plasma discharge. In addition, the plasma display panel 100 includes an electrode. Preferably, it includes a scan electrode (Y) and a sustain electrode (Z) and an address electrode (X) intersecting the scan electrode (Y) and the sustain electrode (Z). The discharge cell is formed at a point where the scan electrode Y, the sustain electrode Z, and the address electrode X cross each other.

The driver 110 supplies a driving signal to the discharge cells of the plasma display panel 100 in a plurality of subfields included in the frame.

In particular, the driving unit 110 changes image data of a partial region of the image displayed on the plasma display panel 100 when the image sticking mode (ISM) is used.

Here, in FIG. 1, only the case in which the driving unit 110 is formed in one board form is illustrated, but in the present invention, the driving unit 110 is divided into a plurality of board forms according to electrodes formed on the plasma display panel 100. It is also possible to lose.

For example, the plasma display device of the present invention drives a scan driver (not shown) for driving the scan electrode (Y), a sustain driver (not shown) for driving the sustain electrode (Z), and an address electrode (X). It can be divided into a data driver (not shown).

The driving unit 110, which is a main feature of the plasma display device of the present invention, will be more clearly described later.

Here, an example of the structure of the plasma display panel 100 will be described in detail with reference to FIGS. 2A to 2B.

2A to 2B are views for explaining an example of the structure of the plasma display panel included in the plasma display device of the present invention.

First, referring to FIG. 2A, a plasma display panel according to the present invention includes a front panel 201 including an electrode, preferably a front substrate 201 on which scan electrodes 202 and Y and sustain electrodes 203 and Z are formed. A rear panel including a back substrate 211 on which an electrode intersecting the scan electrodes 202 and Y and the sustain electrodes 203 and Z, preferably the address electrodes 213 and X, are formed. 210 is made of a combination.

Here, the electrodes formed on the front substrate 201, preferably the scan electrodes 202 and Y and the sustain electrodes 203 and Z, generate a discharge in a discharge space, that is, a discharge cell, and at the same time Maintain the discharge.

The dielectric layer, preferably on the front substrate 201 where the scan electrodes 202 and Y and the sustain electrodes 403 and Z are formed to cover the scan electrodes 202 and Y and the sustain electrodes 203 and Z. Upper dielectric layer 204 is formed.

This upper dielectric layer 204 limits the discharge current of the scan electrodes 202 and Y and the sustain electrodes 203 and Z and insulates the scan electrodes 202 and Y from the sustain electrodes 203 and Z.

A protective layer 205 is formed on the top surface of the upper dielectric layer 204 to facilitate discharge conditions. The protective layer 205 is formed by, for example, depositing a material such as magnesium oxide (MgO) over the upper dielectric layer 204.

Meanwhile, the electrodes formed on the rear substrate 211, preferably the address electrodes 213 and X, are electrodes for applying a data signal to the discharge cells.

A dielectric layer, preferably a lower dielectric layer 215 is formed on the rear substrate 211 on which the address electrodes 213 and X are formed to cover the address electrodes 213 and X.

This lower dielectric layer 215 insulates the address electrodes 213, X.

A discharge space, that is, a partition 212, such as a stripe type or a well type, is formed on the lower dielectric layer 215 to partition the discharge cells. Accordingly, discharge cells such as red (R), green (G), and blue (B) are formed between the front substrate 201 and the rear substrate 211.

Here, a predetermined discharge gas is filled in the discharge cell partitioned by the partition wall 212.

In addition, a phosphor layer 214 is formed in a discharge cell partitioned by the partition 212 to emit visible light for image display during address discharge. For example, red (R), green (G), and blue (B) phosphor layers may be formed.

In the plasma display panel according to the present invention described above, the driving signal is driven by the driving unit 110 of FIG. 1 to at least one of the scan electrodes 202 and Y, the sustain electrodes 203 and Z, and the address electrodes 213 and X. When is supplied, discharge occurs in the discharge cell partitioned by the partition 212.

Then, vacuum ultraviolet rays are generated in the discharge gas filled in the discharge cells, and the vacuum ultraviolet rays are applied to the phosphor layer 214 formed in the discharge cells. Then, a predetermined visible light is generated in the phosphor layer 214, and the visible light is emitted to the outside through the front substrate 201 in which the upper dielectric layer 204 is formed. A predetermined image is displayed on the outer surface.

Meanwhile, in the description of FIG. 2A, only the case where the scan electrodes 202 and Y and the sustain electrodes 203 and Z are each formed of one layer is illustrated and described. However, the scan electrodes 202 and Y or the It is also possible that at least one of the sustain electrodes 203 and Z consists of a plurality of layers. This will be described with reference to FIG. 2B.

Referring to FIG. 2B, the scan electrodes 202 and Y and the sustain electrodes 203 and Z may be formed of two layers, respectively.

In particular, in consideration of light transmittance and electrical conductivity, the scan electrodes 202 and Y and the sustain electrodes 203 and Z are opaque silver (Ag) to emit light generated in the discharge cell to the outside and to secure driving efficiency. Bus electrodes 202b and 203b and transparent electrodes 202a and 203a made of transparent indium tin oxide (ITO).

As such, the reason why the scan electrodes 202 and Y and the sustain electrodes 203 and Z include the transparent electrodes 202a and 203a is that when visible light generated in the discharge cells is emitted to the outside of the plasma display panel. To be released effectively.

In addition, the reason why the scan electrodes 202 and Y and the sustain electrodes 203 and Z include the bus electrodes 202b and 203b is that the scan electrodes 202 and Y and the sustain electrodes 203 and Z are transparent electrodes. In the case of including only 202a and 203a, the driving efficiency can be reduced because the electrical conductivity of the transparent electrodes 202a and 203a is relatively low, so that the transparent electrodes 202a and 203a can cause such a reduction in the driving efficiency. To compensate for the low electrical conductivity.

2A to 2B, only one example of the plasma display panel of the present invention is shown and described, and it is to be understood that the present invention is not limited to the plasma display panel having the structure as shown in FIGS. 2A to 2B. For example, the plasma display panel of FIGS. 2A to 2B shows only the case where the upper dielectric layer 204 and the lower dielectric layer 215 are each one layer, but the upper dielectric layer 204 and At least one or more of the lower dielectric layers 215 may be formed of a plurality of layers.

In view of the above, the plasma display panel which can be applied to the plasma display device of the present invention is provided with address electrodes X and 213, and other conditions are acceptable.

An example of the operation of the plasma display apparatus of the present invention including the plasma display panel will be described with reference to FIGS. 3 to 4.

FIG. 3 is a diagram for explaining a frame for implementing gray levels of an image in the plasma display apparatus of the present invention.

4 is a view for explaining an example of the operation of the plasma display device of the present invention in detail.

First, referring to FIG. 3, in the plasma display device of the present invention, a frame for implementing gray levels of an image is divided into several subfields having different emission counts. Although not shown, each subfield may further include a reset period for initializing all discharge cells, an address period for selecting discharge cells to be discharged, and a sustain period for implementing gray levels according to the number of discharges. Sustain Period).

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. Each of the subfields SF1 to SF8 is divided into a reset period, an address period, and a sustain period.

Meanwhile, the gray scale weight of the corresponding subfield may be set by adjusting the number of sustain pulses supplied in the sustain period. That is, a predetermined gray scale weight can be given to each subfield using the sustain period. For example, the gray scale weight of each subfield is 2 ⁿ by setting the gray scale weight of the first subfield to 2 ⁰ and the gray scale weight of the second subfield to 2 ¹ (where n = 0, 1). , 2, 3, 4, 5, 6, and 7) to increase the gray scale weight of each subfield. As such, by adjusting the number of sustain pulses supplied in the sustain period of each subfield according to the gray scale weight in each subfield, gray levels of various images are realized.

The plasma display device of the present invention uses a plurality of frames to display an image of one second. For example, 60 frames are used to display an image of 1 second.

In FIG. 3, only one frame is composed of eight subfields. However, the number of subfields forming one frame may be changed in various ways. For example, one frame may be configured with 12 subfields from the first subfield to the twelfth subfield, or one frame may be configured with 10 subfields.

The image quality of the image implemented by the plasma display apparatus implementing the gray level of the image using the frame may be determined according to the number of subfields included in the frame. That is, when 12 subfields are included in a frame, gray levels of 2 ¹² images may be expressed. When 8 subfields are included in a frame, gray levels of 2 ⁸ images may be realized.

Also, in FIG. 3, subfields are arranged according to the order of increasing the magnitude of gray scale weight in one frame. Alternatively, subfields may be arranged in the order of decreasing gray scale weight in one frame. Subfields may be arranged regardless of the weight.

Next, referring to FIG. 4, an example of an operation of the plasma display apparatus of the present invention in any one of a plurality of subfields included in the frame shown in FIG. 3 is illustrated.

Referring to FIG. 4, in the plasma display apparatus of FIG. 1, the driving unit 110 may apply a ramp-up signal in which a voltage gradually increases to the scan electrode Y in a setup period of a reset period. have.

Due to this rising ramp signal, a weak dark discharge, that is, a setup discharge, occurs in the discharge cell. This setup discharge causes a certain amount of wall charges to accumulate in the discharge cell.

In addition, in the set-down period after the setup period, a ramp-down that ramps down gradually from a predetermined positive voltage lower than the peak voltage of the ramp-up signal after applying the ramp lamp signal to the scan electrode Y. Signal can be applied.

As a result, weak erase discharge, that is, set-down discharge, occurs in the discharge cell. This set-down discharge erases a part of the wall charges accumulated in the discharge cell by the previous setup discharge, and the wall charges such that the address discharge can be stably generated in the discharge cell remain uniformly.

In the address period after the reset period including the set-up period and the set-down period, a scan signal Scan falling from the scan reference voltage Vsc is applied to the scan electrode Y. The scan signal Scan signal preferably has a negative scan voltage (−Vy).

In addition, the driver 110 may apply a data signal to the address electrode X when the scan signal Scan is applied to the scan electrode Y.

In addition, the sustain bias signal Vzb is applied to the sustain electrode Z in the address period in order to prevent the occurrence of an erroneous discharge due to the interference of the sustain electrode Z in the address period.

In the address period, the voltage difference between the negative scan voltage (-Vy) of the scan signal Scan and the data voltage Vd of the data signal and the wall voltage generated by the wall charges generated in the reset period are added to the data signal. An address discharge is generated in the discharge cell to which the data voltage Vd is applied.

In this discharge cell selected by the address discharge, a wall charge is formed to the extent that discharge can occur when the sustain voltage Vs of the sustain signal SUS is applied.

In the sustain period after the address period, the scan driver 302 and the sustain driver 303 apply the sustain signal SUS to the scan electrode Y or the sustain electrode Z. FIG.

Accordingly, the discharge cells selected by the address discharge have the scan voltage (Y) and the sustain electrode (Z) when the wall voltage and the sustain voltage (Vs) of the sustain signal (SUS) are added while the sustain signal (SUS) is applied. Sustain discharge, that is, display discharge, occurs between them. Accordingly, a predetermined image is implemented on the plasma display panel.

In the above description, only the case where the sustain signal is alternately applied to the scan electrode Y and the sustain electrode Z is illustrated and described. It is also possible to apply.

For example, the sustain signal may be applied only to the scan electrode Y among the scan electrode Y or the sustain electrode Z.

More specifically, either the scan electrode Y or the sustain electrode Z rises from the ground level GND to the positive sustain voltage (+ Vs), and again at the ground level GND, the negative sustain voltage ( A sustain signal of a type falling down to -Vs) is applied.

At this time, the voltage of the ground level GND is applied to the other electrode.

By using such a method, a predetermined image may be implemented on the plasma display panel.

When such an image is continuously displayed on the plasma display panel, the image is set to a fixed image sticking mode (ISM).

In the fixed afterimage mode, the driving unit of the plasma display apparatus of the present invention changes the image data of a part of the image displayed on the plasma display panel. This is as follows.

Here, before describing a method of changing image data of a portion of an image displayed on the plasma display panel for easier understanding of the present invention, the fixed persistence mode will be described with reference to FIGS. 5 to 6. Let's look at it.

FIG. 5 is a diagram for describing a fixation afterimage mode setting in consideration of the duration of the same image.

6 is a diagram for explaining the fixed afterimage mode setting in consideration of the average power level.

First, referring to FIG. 5, when the image 510 of 'A' is displayed on the plasma display panel 500, the fixed afterimage mode may be set according to the duration of displaying the image 510.

For example, the sticking afterimage mode may start from a time point when the image 510 of 'A' lasts for 4 minutes or more on the plasma display panel 500.

That is, the fixed afterimage mode may occur when substantially the same image is continuously displayed on the plasma display panel 500 for a predetermined time or more.

Here, if the time for which the same image is continuously displayed is excessively short, the discharge is not likely to be stuck in the discharge cell. On the other hand, if the time for which the same image is continuously displayed is excessively long, it is discharged in the discharge cell. This excessive fixation may increase the likelihood that it is difficult to improve the afterimage even if a part of the data of the image is changed as in the present invention.

In consideration of this, it is preferable that the predetermined time for which the substantially same image is continuously displayed is about 1 minute or more and 10 minutes or less.

Next, the fixed afterimage mode may be set according to the average power level APL of the image displayed on the plasma display panel 600 of FIG. 6.

Here, the average power level is as follows.

The average power level is determined according to the number of discharge cells that are turned on among the discharge cells of the plasma display panel 600. That is, it is determined according to the area in which the image is displayed on the plasma display panel 600.

Here, as the average power level APL increases, the number of sustain pulses per gray level decreases, and as the average power level APL decreases, the number of sustain pulses per gray level increases.

For example, when an image is displayed on a portion of a relatively large area on the screen of the plasma display panel 600 as shown in (b), that is, when the area 620 where the image is displayed is relatively large, When the number of discharge cells that are turned on among the plurality of discharge cells formed in the plasma display panel 600 is relatively large (in this case, the APL level is relatively large), the number of discharge cells that contribute to image display. Since the number is relatively large, the number of sustain pulses per unit gray level supplied to each of the discharge cells contributing to the image display is relatively small, thereby reducing the total amount of power consumption.

On the contrary, when the image is displayed only on a portion of a relatively small area on the screen of the plasma display panel 600 as shown in (a), that is, when the area 610 where the image is displayed is relatively small, the plasma is expressed differently. When the number of discharge cells that are turned on among the plurality of discharge cells formed on the display panel 600 is relatively small (in this case, when the APL level is relatively small), the number of discharge cells that contribute to image display is relatively small. Because of this, the number of sustain pulses per unit gray scale supplied to each of the discharge cells contributing to the image display is relatively large. This increases the luminance of the portion where the image is displayed, thereby preventing a sudden increase in the total power consumption while increasing the overall luminance.

For example, when the average power level is a level, the number of sustain pulses per gray level is N accordingly.

In addition, when the average power level is a b level higher than the above-described a level, the number of sustain pulses per gray level corresponding thereto is M less than N described above.

The fixed afterimage mode may be set according to the average power level, for example, when the image of the average power level substantially the same as the reference numeral 610 is displayed on the plasma display panel 600 for a predetermined time or more, as shown in (a). Can be set to afterimage mode.

Here, the predetermined time for which the image of substantially the same average power level is continuously displayed is preferably about 1 minute or more and 10 minutes or less.

The operation of the driving unit of the plasma display apparatus of the present invention in the fixed afterimage mode will be described below.

FIG. 7 is a view for explaining an example of a method of changing image data in a fixed afterimage mode. FIG.

Referring to FIG. 7, it is assumed that an image of a window type is displayed on the plasma display panel 700 as indicated by reference numeral 710.

The image of the symbol 710 may be divided into A, B, C, D, E, F, G, H, I, J, K. L, M, N, O, and P regions.

Herein, the driving unit of the plasma display apparatus of the present invention selects one or more areas from A to P and changes image data corresponding to the selected area.

A detailed embodiment of such a method of changing image data will be described with reference to FIG. 8.

FIG. 8 is a diagram for describing a specific embodiment of the method of FIG. 7.

Referring to FIG. 8, the image data may be changed by selecting a partial region of the image displayed on the plasma display panel 700 and turning off image data of the selected region.

For example, as shown in (a), in the first step, the image data of the area A of the areas A to P is turned off. That is, in the first step, the image is not displayed in the A area.

Next, as shown in (b), the image data of the area A is turned on again. That is, the image is displayed again in the A area.

In addition, in the second step, the image data of the region B is turned off.

In this manner, it is preferable to turn off the image data of the C region in the third step as shown in (c), and to turn off the image data of the D region as shown in (d) in the fourth step.

As described above, when the image data of a part of the image displayed on the plasma display panel 700 is changed in the fixed afterimage mode, the shape of the discharge in the discharge cell that is likely to be stuck is shaken, thereby suppressing the occurrence of the afterimage. have.

Here, the region for changing the image data may be formed in one discharge cell unit or may be formed in a pixel unit composed of a plurality of discharge cells. This will be described with reference to FIGS. 9A to 9B.

9A to 9B are diagrams for explaining an example of a method for setting an area.

First, referring to FIG. 9A, at least one of regions A to P in FIG. 8 is formed of one discharge cell unit. That is, one discharge cell is set to one area.

For example, in a case where the total six discharge cells are all turned on and set to the fixed afterimage mode, in the first step, as shown in (a), the first red (R) discharge cell of the total six discharge cells is turned off. Can be.

Next, in the second step, the first red (R) discharge cell may be turned on again, and as shown in (b), the first green (G) discharge cell of the total six discharge cells may be turned off.

Next, in the third step, the first green (G) discharge cell may be turned on again, and as shown in (c), the first blue (B) discharge cell of the total six discharge cells may be turned off.

Next, in the fourth step, the first blue (B) discharge cell may be turned on again, and as shown in (d), the second red (R) discharge cell of the total six discharge cells may be turned off.

In this way, the image data can be changed for each discharge cell.

Next, referring to FIG. 9B, at least one of the areas A to P in FIG. 8 is formed in a pixel unit including a plurality of discharge cells. That is, one pixel is set to one area.

For example, in the case where all four pixels 900, 910, 920, and 930 each consisting of red (R), green (G), and blue (B) discharge cells are all turned on and set to the fixed afterimage mode, In the first step, as shown in (a), the first pixel 900 may be turned off.

Next, in the second step, the first pixel 900 may be turned on again, and as shown in (b), the second pixel 910 may be turned off.

In this manner, image data can be changed for each pixel.

In the above, only the case of setting one area in units of discharge cells or pixels is illustrated and described. However, this is only an example of a method of setting an area, and one area in units of 10 discharge cells or 10 pixels. It is also possible to make various changes such as setting.

As described above, in the fixed afterimage mode, it is preferable to change a part of the image data and to adjust the number of sustain signals per gray level for displaying an image. This will be described with reference to FIG. 10.

FIG. 10 is a diagram for describing a method of controlling the number of sustain signals per gray level in a fixed afterimage mode. Referring to FIG.

Referring to FIG. 10, in the plasma display device of the present invention, it is preferable to gradually reduce the number of sustain signals per gray level as the duration of the fixed afterimage mode increases in the fixed afterimage mode.

For example, suppose that the number of sustain signals per gray level in a particular image is n.

Here, if a specific image is continuously set on the plasma display panel and set to the fixed afterimage mode at time t0, the number of sustain signals per gray level may be set to n1 less than n at time t1 in the fixed afterimage mode.

In addition, when the fixed afterimage mode continues and reaches the time t2, the number of sustain signals per gray level may be set to n2 less than n1.

As described above, when the number of sustain signals per gradation is reduced in the sticking afterimage mode, in particular, when the number of the sustain signals per gradation is decreased as the duration of the sticking afterimage mode increases, the intensity of the sustain discharge generated in the discharge cell is reduced. Is reduced and thus the distribution of the wall charges stuck in the discharge cell can be relatively easily shaken. This improves afterimages.

Meanwhile, when changing image data for each region, the order of changing image data may be changed. This is as follows.

11 is a diagram for explaining a procedure of changing video data.

Referring to FIG. 11, the order of changing the image data is reverse to that of FIG. 8.

For example, as shown in (a), in the first step, image data of the P area among the areas from A to P is turned off. That is, in the first step, the image is not displayed in the P area.

Next, as shown in (b), the image data of the P area is turned on again. That is, the image is displayed again in the P area.

In addition, in the second step, the image data of the O region is turned off.

In this manner, it is preferable to turn off the image data of the N area in the third step as shown in (c), and to turn off the image data of the M area as shown in (d) in the fourth step.

As described above, when the image data of a part of the image displayed on the plasma display panel 700 is changed in the fixed afterimage mode, the order of change may be variously adjusted.

Meanwhile, in FIG. 8, the data change order is forward. Here, in FIG. 11, the data is reversed, but the data can be changed randomly.

For example, the order of data change is in the order of areas B, C, A, F, P, O, H, and D.

In the above description, only the selection of one region of the plurality of regions and the change of the image data of the selected region have been described. However, differently, the plurality of regions are selected and the image data of the plurality of regions selected together are changed. It is also possible. This will be described with reference to FIG. 12.

12 is a diagram for explaining an example of a method of simultaneously changing video data of a plurality of areas.

Referring to FIG. 12, in the first step, for example, as shown in (a), image data of an area A of areas A to P is turned off. That is, in the first step, the image is not displayed in the A area.

Next, as shown in (b), the image data of the area A is turned on again. That is, the image is displayed again in the A area.

In addition, in the second step, image data of the B area and the C area is turned off.

In this manner, it is preferable to turn off the image data of the D area and the H area in the third step as shown in (c), and to turn off the image data of the F area and the G area as shown in (d) in the fourth step.

As described above, when the image data of the partial region of the image displayed on the plasma display panel 700 is changed in the fixed afterimage mode, the number of regions for changing data may be variously adjusted.

In the above description, only the method of changing the image data by selecting one or more regions among the plurality of regions and turning off the image data of the selected region is described, but it is also possible to change the image data in a different manner. This is as follows.

FIG. 13 is a view for explaining another example of a method of changing image data in a fixed image retention mode.

Referring to FIG. 13, it is assumed that a lattice type image is displayed on the plasma display panel 1300 as indicated by reference numeral 1310.

The image 1310 may be divided into A, B, C, D, E, F, G, H, I, J, K. L, M, N, O, and P regions. Here, brightly displayed areas A, C, F, H, I, K, N, and P are areas where an image is displayed, that is, areas that are turned on, and darkly displayed B, D, E, G, J, L, M, O The area is considered to be an area where no image is displayed, that is, an area that is turned off.

Here, the driving unit of the plasma display apparatus of the present invention selects one or more of the areas from A to P, and changes the image data corresponding to the selected area. Particularly, the off state of the image data of the selected area is on. (On), the state which is on is turned off to change the video data.

A detailed embodiment of such a method of changing image data will be described with reference to FIG. 14.

14 is a view for explaining a specific embodiment of the method of FIG.

14, a portion of an image displayed on the plasma display panel 1300 may be selected, and image data of the selected region may be turned off or on to change the image data.

For example, as shown in (a), in the first step, the image data of the area A which is turned on among the areas A to P is turned off. That is, in the first step, the image is not displayed in the area A in which the image is displayed.

Next, as shown in (b), the image data of the area A is turned on again. That is, the image is displayed again in the A area.

In addition, in the second step, the image data of the region B which has been turned off is turned on.

In this way, it is preferable to turn off the image data of the C region which was turned off in the third step as shown in (c), and to turn on the image data of the D region which was turned off as shown in (d) in the fourth step.

As described above, by turning off or turning on image data of a partial region of an image displayed on the plasma display panel 1300 in the sticking afterimage mode, when the image data is changed, the shape of the discharge in the discharge cell that is likely to stick is shaken. By giving it, the occurrence of an afterimage can be suppressed.

Next, FIG. 15 is a view for explaining another example of a method of changing image data in a fixed image retention mode.

Referring to FIG. 15, it is assumed that an image of a lattice type having various gray scale values is displayed on the plasma display panel 1500 as indicated by reference numeral 1510.

The image 1310 may be divided into A, B, C, D, E, F, G, H, I, J, K. L, M, N, O, and P regions. Here, the brightest A, F, H, K, M, N, and P areas are areas in which the image of the first gradation is displayed, that is, the brightest area, and B, D, G, I, The areas L and O are displayed in which the image of the second gray level lower than the first gray level is displayed, and the areas C, E, and J, which are darkest, are regarded as the area in which the image of the third gray level lower than the second gray level is displayed.

Here, the driving unit of the plasma display apparatus of the present invention selects one or more of the areas from A to P, and changes the image data corresponding to the selected area, in particular by adjusting the gain of the image data of the selected area to adjust the image. Change the data.

For example, although not shown, in the first step, the image data of the area A indicated by the first gray level among the areas A to P is changed to the image data of the third gray level.

That is, by reducing the gain of the image data of the area A, the gray level of the image displayed in the area A is reduced.

Next, in the second step, the image data of the area A is reduced to the first gray level, and the image data of the area B indicated by the second gray level is converted into the image data of the third gray level.

Next, in the third step, the image data of the area B is reduced to the second gray level, and the image data of the area C, which is displayed in the third gray level, is converted into the image data of the first gray level.

That is, the gray level of the image displayed in the area A is increased by increasing the gain of the image data in the area C.

As described above, by adjusting the gain of the image data of the partial region of the image displayed on the plasma display panel 1500 in the fixed afterimage mode, when the image data is changed, the shape of the discharge in the discharge cell that is likely to be fixed is shaken. By doing so, generation of afterimages can be suppressed.

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 above in detail, the plasma display apparatus of the present invention has the effect of reducing the occurrence of an afterimage by changing a part of the image data in the fixed afterimage mode, thereby improving the image quality.

Claims (10)

A plasma display panel displaying an image using plasma discharge; And A driving unit for dividing an image displayed on the plasma display panel into a plurality of regions, selecting one or more of the plurality of regions, and changing image data of the selected region in the fixed afterimage mode; Plasma display device comprising a. delete The method of claim 1, The driving unit And turning off the image data of the selected area to change the image data. The method of claim 1, The driving unit Plasma display device according to claim 1, wherein the image data of the selected area is turned on and the off state is turned off. The method of claim 1, The driving unit And changing the image data by adjusting a gain of the image data of the selected region. The method of claim 1, At least one of the plurality of regions is formed of a discharge cell unit. The method of claim 1, At least one of the plurality of regions is formed in a pixel unit including a plurality of discharge cells. The method of claim 1, The fixed afterimage mode is And the substantially same image is displayed on the plasma display panel for a predetermined time or more. The method of claim 1, The fixed afterimage mode is The plasma display apparatus of claim 1, wherein the plasma display panel displays an image of an average power level (APL) substantially equal to or longer than a predetermined time. The method according to claim 8 or 9, And the predetermined time is 1 minute or more and 10 minutes or less.

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