KR20050036260A - Method and apparatus of preventing image sticking in plasma display panel - Google Patents

Abstract

The present invention relates to a method of preventing afterimage generation of a plasma display panel capable of sufficiently displaying the luminance of a screen to be displayed while preventing generation of permanent afterimages that may occur when a still image is continued for a long time. In the method for preventing afterimage generation of a plasma display panel according to the present invention, there is provided a method for preventing afterimage generation of a plasma display panel, the method comprising: a still image sensing step; Afterimage prevention step is provided. The still image detecting step detects whether an input image to be displayed on the screen is a still image. In the afterimage prevention step, the afterimage is repeatedly prevented by increasing or decreasing the brightness of the displayed image according to whether the input image is a still image.

Description

Method and apparatus for preventing afterimage occurrence of plasma display panel {Method and apparatus of preventing image sticking in plasma display panel}

The present invention relates to a method of driving a plasma display panel, and more particularly, to sufficiently display a luminance of a screen to be displayed while preventing the occurrence of permanent image sticking that may occur when a still image continues for a long time. The present invention relates to a method for preventing afterimage generation of a plasma display panel.

1 is a perspective view showing an internal structure of a conventional three-electrode surface discharge plasma display panel. FIG. 2 is a cross-sectional view illustrating a configuration of a unit display cell of the panel of FIG. 1.

Referring to the drawings, between the front and rear glass substrates 10 and 13 of the conventional surface discharge plasma display panel 1, the address electrode lines A _R1 , A _G1 , ..., A _Gm , A _Bm ), Dielectric layers 11 and 15, Y electrode lines (Y ₁ , ..., Y _n ), X electrode lines (X ₁ , ..., X _n ), fluorescent layer 16, partition wall 17 ) And a magnesium monoxide (MgO) layer 12 as a protective layer.

The address electrode lines A _R1 , A _G1 ,..., A _Gm , A _Bm are formed in a predetermined pattern on the front side of the rear glass substrate 13. The lower dielectric layer 15 is entirely applied in front of the address electrode lines A _R1 , A _G1 ,..., A _Gm , A _Bm . In front of the lower dielectric layer 15, barrier ribs 17 are formed in a direction parallel to the address electrode lines A _R1 , A _G1 ,..., A _Gm , A _Bm . These partitions 17 function to partition the discharge area of each discharge cell and to prevent optical cross talk between each discharge cell. The fluorescent layer 16 is formed between the partition walls 17.

The X electrode lines (X ₁ , ..., X _n ) and the Y electrode lines (Y ₁ , ..., Y _n ) are the address electrode lines (A _R1 , A _G1 , ..., A _Gm , A _Bm ) is formed in a predetermined pattern on the back of the front glass substrate 10 to be orthogonal to each other. Each intersection sets a corresponding discharge cell. Each X electrode line (X ₁ , ..., X _n ) and each Y electrode line (Y ₁ , ..., Y _n ) have a conductivity and a transparent electrode line made of a transparent conductive material such as indium tin oxide (ITO). Metal electrode lines for heightening are formed in combination. The front dielectric layer 11 is formed by applying the entire surface to the rear of the X electrode lines X ₁ ,..., X _n and the Y electrode lines Y ₁ ..., Y _n . A protective layer 12 for protecting the panel 1 from a strong electric field, for example, a magnesium monoxide (MgO) layer, is formed by applying the entire surface to the back of the front dielectric layer 11. The plasma forming gas is sealed in the discharge space 14.

As a driving method of the plasma display panel 1 having the structure described above, an address-display separation driving method which is mainly used is disclosed in US Pat.

3 is a block diagram illustrating a conventional driving device of the plasma display panel of FIG. 1.

A typical driving device 2 of the plasma display panel 1 includes an image processor 26, a logic controller 22, an address driver 23, an X driver 24, and a Y driver 25. The image processing unit 26 converts an external analog image signal into a digital signal, for example, an internal image signal, for example, 8-bit red (R), green (G), and blue (B) image data, a clock signal, vertical and horizontal, respectively. Generate synchronization signals. The logic controller 22 generates driving control signals S _A , S _Y , and S _X according to an internal image signal from the image processor 26.

In this case, the driving unit such as the address driver 23, the X driver 24, and the Y driver 25 receives input from the driving control signals S _A , S _Y , and S _X , and generates respective driving signals. The applied driving signal to each of the electrode lines.

That is, the address driver 23 processes the address signal S _A among the drive control signals S _A , S _Y , and S _X from the logic controller 22 to generate a display data signal, and generates the displayed display. The data signal is applied to the address electrode lines. The X driver 24 processes the X driving control signal S _X among the driving control signals S _A , S _Y , and S _X from the logic controller 22 and applies the X driving control signal S _X to the X electrode lines. The Y driver 25 processes the Y driving control signal S _Y among the driving control signals S _A , S _Y , and S _X from the logic controller 22 and applies the Y driving control signal S _Y to the Y electrode lines.

4 is a timing diagram illustrating a conventional driving method of the plasma display panel of FIG. 1.

Referring to the drawing, a unit frame is divided into eight subfields SF1, ..., SF8 to realize time division gray scale display. Each subfield SF1, ..., SF8 is divided into a reset period (not shown), an address period A1, ..., A8, and a sustain discharge period S1, ..., S8. do.

The luminance of the plasma display panel is proportional to the length of the sustain discharge cycles S1, ..., S8 occupied in the unit frame. The lengths of the sustain discharge cycles S1, ..., S8 occupy a unit frame are 255T (T is the unit time). At this time, a time corresponding to 2n is set in the sustain discharge period Sn of the nth subfield SFn. Accordingly, when the subfield to be displayed among the eight subfields is appropriately selected, it can be seen that display of 256 gray levels can be performed including all zero (zero) gray levels that are not displayed in any of the subfields.

FIG. 5 is a timing diagram illustrating driving signals applied to electrode lines of the plasma display panel of FIG. 1 in a unit sub-field of FIG. 4.

In FIG. 5, reference numeral S _{AR1 ..ABm} denotes a driving signal applied to each address electrode line (A _R1 , A _G1 ,..., A _Gm , A _{Bm in} FIG. 1), and S _{X1 .. Xn} denotes an X electrode. Drive signal applied to the lines (X ₁ , ..., X _n of FIG. 1), and S _{Y1 ..Yn} is applied to each Y electrode line (Y ₁ , ..., Y _n of FIG. 1). Indicates a driving signal.

Referring to the drawing, in the reset period PR of the unit sub-field SF, first, the voltage applied to the X electrode lines X ₁ ,..., X _n is set from the ground voltage V _G to the second. for the voltage (V _S) for example, then continue to rise to 155 volts (V). Here, the ground voltage V _G is applied to the Y electrode lines Y ₁ ,..., Y _n and the address electrode lines A _R1 , A _G1 ,..., A _Gm , A _Bm .

Next, the voltage applied to the Y electrode lines Y ₁ ,..., Y _n is third from the second voltage V _S , for example, from 155 volts V to a second voltage than the second voltage V _S. The highest voltage V _SET + V _{S that} is as high as the voltage V _SET is continuously raised to, for example, 355 volts (V). Here, the ground voltage V _G is applied to the X electrode lines X ₁ ,..., X _n and the address electrode lines A _R1 , A _G1 ,..., A _Gm , A _Bm .

Next, in the state where the voltage applied to the X electrode lines X ₁ ,..., X _n is maintained at the second voltage V _S , the Y electrode lines Y ₁ ,..., Y _n The voltage applied to) is continuously lowered from the second voltage V _S to the ground voltage V _G. Here, the ground voltage V _G is applied to the address electrode lines A _R1 , A _G1 ,..., A _Gm , and A _Bm .

Accordingly, in the address period (PA), leading address is applied to a display data signal to the electrode lines, the the second voltage (V _S) lower fourth voltage (V _SCAN) to bias the Y-electrode line than the (Y ₁ As a scan signal of the ground voltage V _G is sequentially applied to the ..., Y _n ), smooth addressing may be performed. The display data signal applied to each of the address electrode lines A _R1 , A _G1 , ..., A _Gm , A _Bm has a positive address voltage V _A when the discharge cell is selected, and a ground voltage when the discharge cell is not. (V _G ) is applied. Accordingly, when the display data signal of the positive address voltage V _A is applied while the scan pulse of the ground voltage V _G is applied, wall charges are formed by the address discharge in the corresponding discharge cell. Wall charges do not form. Here, for more accurate and efficient address discharge, the second voltage V _S is applied to the X electrode lines X ₁ ,..., X _n .

In the sustain discharge period PS that follows, the second voltage V _S is applied to all of the Y electrode lines Y ₁ , ..., Y _n and the X electrode lines X ₁ , ..., X _n . The display sustain pulse is alternately applied, causing a discharge for display retention in the discharge cells in which wall charges are formed in the corresponding address period PA.

When the input image signal of the plasma display panel is input for the long time with the same signal, permanent sticking may occur due to damage of the phosphor and the protective layer MgO. In order to prevent this, an afterimage preventing method of the plasma display panel may be used.

6 is a graph schematically illustrating a method for preventing afterimage generation of a conventional plasma display panel.

Referring to the drawings, in the conventional method of preventing afterimage generation of a plasma display panel, it is determined whether a received image input signal is a still image, and in the case of a still image, the number of sustain pulses is gradually reduced. In this case, the number of sustain pulses may be expressed as luminance as shown in the figure, and the graph shows a luminance reduction algorithm by decreasing the number of sustain pulses at the time of inputting a still image. In this case, it is based on the 1% window.

That is, when the same still picture is detected for a predetermined time t0, the received video input signal is determined to be a still picture, and the number of sustain pulses is reduced step by step. At this time, when the number of the sustaining pulses is reduced in stages to reach a predetermined time t1, the number of the sustaining pulses that are decreased is saturated.

However, in the conventional method of preventing afterimage generation, the number of sustaining pulses is unilaterally reduced, and thus the luminance is reduced, so that the change in brightness of the screen can be easily detected with the naked eye. That is, in this case, although there is an effect of reducing the permanent afterimage in the still image, there is a problem that the luminance of the screen to be displayed is not sufficiently expressed.

The main purpose of the display, such as the display of an image or a character, when the same video signal is prolonged for a long time to deliver the brightness, which results in sacrificing the display of the target brightness by the down rate shown.

The present invention is to solve the above problems, the plasma display panel that can sufficiently display the brightness of the screen to be displayed while preventing the occurrence of permanent image sticking (phenomena) that may occur when the still image is prolonged for a long time An object of the present invention is to provide a method for preventing the occurrence of afterimages.

In accordance with an aspect of the present invention, there is provided a method for preventing afterimage generation of a plasma display panel, the method comprising: a still image sensing step of preventing afterimage generation of a plasma display panel; Afterimage prevention step is provided.

The still image detecting step detects whether an input image to be displayed on the screen is a still image. In the afterimage prevention step, the afterimage is repeatedly prevented by increasing or decreasing the brightness of the displayed image according to whether the input image is a still image.

In the afterimage generation prevention step, if the input image is determined to be a still image by the detection in the still image detection step, the afterimage prevention step is performed, and when the input image is not a still image, the afterimage generation is performed. It is preferable not to perform the prevention step.

The afterimage prevention step includes a first step, a second step, and a third step that are repeatedly performed. In the first step, the brightness of the displayed image is reduced from the first level to the second level. In the second step, the brightness of the displayed image is maintained at the second level for a predetermined time. In the third step, the brightness of the displayed image is increased from the second level to the first level.

In this case, each of the first, second, and third steps includes a still image determination step and a brightness adjustment step. In the still image determination step, it is determined whether the input image is a still image. In the brightness adjustment step, the brightness of the displayed image is adjusted according to whether the input image is a still image.

In the afterimage prevention step, if it is determined that the input image is not a still image, it is preferable to end the performance of the brightness adjustment step.

According to another aspect of the present invention, there is provided a method for preventing afterimage generation of a plasma display panel, wherein discharge cells are formed in regions where address electrode lines cross with respect to sustain electrode line pairs in which X electrode lines and Y electrode lines are alternately arranged side by side A method for preventing afterimage generation of a plasma display panel in which a screen corresponding to an input image is displayed by applying a predetermined number of sustain pulses to the X electrode lines and the Y electrode lines for each frame as a display period, wherein the afterimage detection step is performed. Wow; Afterimage prevention step is provided.

In the still image detection step, it is detected whether the input image is a still image. In the afterimage prevention step, the afterimage may be prevented by repeatedly decreasing and increasing the number of sustain pulses per frame depending on whether the input image is a still image.

The afterimage prevention step includes a first step, a second step, and a third step that are repeatedly performed. In the first step, the number of sustain pulses per frame is reduced from the first level to the second level. In the second step, the number of sustain pulses per frame is maintained at a second level for a predetermined time. In the third step, the number of sustain pulses per frame is increased from the second level to the first level.

Each of the first, second and third steps includes a still image determination step and a brightness adjustment step. In the still image determination step, it is determined whether the input image is a still image. In the brightness adjustment step, the number of sustain pulses per frame is adjusted according to whether the input image is a still image.

According to another aspect of the present invention, there is provided an afterimage preventing apparatus of a plasma display panel, comprising: a still image detection unit; An afterimage prevention part is provided.

The still image detecting unit detects whether the input image to be displayed on the screen is a still image. The afterimage prevention unit prevents the occurrence of an afterimage by repeatedly decreasing and increasing the brightness of the displayed image according to whether the input image is a still image.

The afterimage prevention unit includes a still image determining unit and a brightness adjusting unit. The still image determination unit determines whether the input image is a still image. The brightness controller adjusts the brightness of the displayed image according to whether the input image is a still image.

According to another aspect of the present invention, there is provided an afterimage preventing apparatus of a plasma display panel, wherein discharge cells are formed in regions where address electrode lines cross with respect to sustain electrode line pairs in which X electrode lines and Y electrode lines are alternately arranged side by side. In the afterimage detection device of the plasma display panel to display a screen corresponding to the input image by applying a predetermined number of sustain pulses per frame as a display period to the X electrode lines and the Y electrode lines, Still image detection unit Wow; An afterimage prevention part is provided.

The still image detector detects whether the input image is a still image. The afterimage generation prevention unit prevents the occurrence of an afterimage by repeatedly decreasing and increasing the number of sustain pulses per frame, depending on whether the input image is a still image.

According to the present invention, it is possible to faithfully display the luminance of the screen to be expressed while preventing generation of permanent afterimages that may occur when the still image is continued for a long time.

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

7 is a flowchart schematically illustrating a method for preventing afterimage generation of a plasma display panel according to an exemplary embodiment of the present invention. FIG. 9 is a graph schematically illustrating a change in the number or brightness of sustain pulses over time by the method of preventing afterimage generation of the plasma display panel of FIGS. 7 and 8.

Referring to the drawings, a method of preventing afterimage generation of a plasma display panel includes: a method of preventing afterimage generation of a plasma display panel to prevent afterimage generation of a plasma display panel, the method comprising: a still image detection step (S102); Afterimage generation prevention steps (S103, S104) are provided.

In the still image detection step (S102), it is detected whether the input image to be displayed on the screen is a still image. In the afterimage prevention step (S103, S104), the afterimage is repeated to decrease and increase the brightness of the displayed image according to whether the input image is a still image.

In the afterimage prevention step (S103, S104), if the input image is determined to be a still image by the detection in the still image detection step (S102), the afterimage prevention step (S103, S104) is performed, and If it is determined that the input image is not a still image, the afterimage prevention steps S103 and S104 may not be performed.

The afterimage prevention steps S103 and S104 include a first step t0 to t1, a second step t1 to t2, and a third step t2 to t3 which are repeatedly performed. In the first steps t0 to t1, the brightness of the displayed image is reduced from the first level L1 to the second level L2. In the second steps t1 to t2, the brightness of the displayed image is maintained at the second level L2 for a predetermined time t2-t1. In the third steps t2 to t3, the brightness of the displayed image is increased from the second level L2 to the first level L1.

In this case, each of the first steps t0 to t1, the second steps t1 to t2, and the third steps t2 to t3 includes a still image determination step S103 and a brightness adjustment step S104. do. In the still image determination step (S103), it is determined whether the input image is a still image. In the brightness adjusting step (S104), the brightness of the displayed image is adjusted according to whether the input image is a still image.

In the afterimage prevention step (S103, S104), if it is determined that the input image is not a still image, it is preferable to terminate the execution of the brightness adjustment step.

At this time, in the present embodiment to adjust the brightness of the screen, there may be a variety of methods for adjusting the brightness of the screen, in particular, it would be preferable to use a method for adjusting the number of sustain pulses per frame.

According to the present invention, when a still image is continuously input for a long time, the image is detected and repeated, and the brightness of the displayed image is repeatedly decreased, thereby preventing the occurrence of permanent image sticking, and unlike the conventional method, the input image is different from the conventional method. Since it is repeated to decrease and increase the brightness based on the brightness of, it is possible to faithfully display the brightness of the screen to be expressed.

8 is a flowchart schematically illustrating a method for preventing afterimage generation of a plasma display panel according to another exemplary embodiment of the present invention. FIG. 9 is a graph schematically illustrating a change in the number or brightness of sustain pulses over time by the method of preventing afterimage generation of the plasma display panel of FIGS. 7 and 8.

Referring to the drawings, a method of preventing afterimage generation of a plasma display panel includes X electrode lines (X ₁ ,..., X _n in FIG. 1) and Y electrode lines (Y ₁ ,..., Y in FIG. 1). _n ) discharge cells are formed in a region where the address electrode lines (A _R1 , A _G1 ,..., A _Gm , A _{Bm in} FIG. 1) intersect with the pair of sustain electrode lines alternately arranged side by side. A predetermined number of sustain pulses are applied to X electrode lines (X ₁ ,..., X _n of FIG. 1) and the Y electrode lines (Y ₁ ,..., Y _n of FIG. 1) for each frame as a display period. A method for preventing afterimage generation of a plasma display panel which is applied to display a screen corresponding to an input image, the method comprising: a still image sensing step (S202); Afterimage generation prevention steps (S203 to S209) are provided.

In the still image detection step (S202), it is detected whether the input image is a still image. In the afterimage prevention step (S203 to S209), the afterimage is repeated to decrease and increase the number of sustain pulses per frame according to whether the input image is a still image.

In the still image detection step (S202), it is possible to detect whether or not the still image according to whether or not the input image signal by comparing the frame unit by comparing the image signal of the previous frame and the current frame. In this case, whether the still image is the same may be determined as the still image when the same image signal is the same as the preset image signal of a predetermined number of consecutive frames. That is, in the present exemplary embodiment, when the video signals of the consecutive frames corresponding to the T0 time are the same, it may be determined as a still picture.

In the afterimage prevention step (S203 to S209), if the input image is determined to be a still image by the detection in the still image detection step (S202), the afterimage prevention step (S203 to S209) is performed, and If it is determined that the input image is not a still image, the afterimage prevention steps S203 to S209 may not be performed.

That is, even when the afterimage prevention steps S203 to S209 are performed, if a change in the input image is detected in the middle of gradually increasing or decreasing the brightness of the input image or the number of sustain pulses per frame, the afterimage prevention step S203 is performed. To S209).

The afterimage prevention steps S203 to S209 include a first step S204, a second step S205, and a third step S206, which are repeatedly performed. In the first step S204, the number of sustain pulses per frame is reduced from the first level L1 to the second level L2. In the second step S205, the number of sustaining pulses per frame is maintained at a second level L2 for a predetermined time period T2-T1. In the third step S206, the number of sustaining pulses per frame is increased from the second level L2 to the first level L1.

At this time, the reduction or increase in the number of sustain pulses per frame in each of the first step (S204), the second step (S205), and the third step (S206) is preferably gradually progressed for a predetermined time, respectively. .

That is, the first step (S204) determines whether the input image is a still image (S202), and determines the time (t) (S203), gradually the same image at a constant time interval while continuing from T0 time to T1 time The number of sustain pulses per frame is reduced from the first level L1 to the second level L2. This determines whether the time t has reached the T3 time from the still image determination (S202) (S207). If the time t has reached the T3 time, the time is initialized (S208). The process of increasing the time (S209) is repeatedly performed.

In the second step S205, it is determined whether the input image is a still image (S202), the time t is determined (S203), and the sustain pulse per frame at regular time intervals while the same image continues from T1 time to T2 time. The number of times is maintained at the second level L2 for a predetermined time (T2-T1). This determines whether the time t has reached the T3 time from the still image determination (S202) (S207). If the time t has reached the T3 time, the time is initialized (S208). The process of increasing the time (S209) is repeatedly performed.

The third step (S206) determines whether the input image is a still image (S202), and determines the time (t) (S203), gradually per frame at regular time intervals while the same image continues from T2 time to T3 time. The number of sustain pulses is increased from the second level L2 to the first level L1. This determines whether the time t has reached the T3 time from the still image determination (S202) (S207). If the time t has reached the T3 time, the time is initialized (S208). The process of increasing the time (S209) is repeatedly performed.

That is, each of the first step S204, the second step S205, and the third step S206 includes a still image determination step S202 and brightness adjustment steps S203 to S209. In the still image determination step (S202), it is determined whether the input image is a still image. In the brightness adjusting steps S203 to S209, the number of sustain pulses per frame is adjusted according to whether the input image is a still image.

In the afterimage prevention step (S203 to S209), if it is determined that the input image is not a still image, it is preferable to terminate the execution of the brightness adjustment step.

10 is a block diagram schematically illustrating an apparatus for preventing afterimage generation of a plasma display panel according to an exemplary embodiment of the present invention. FIG. 11 is a block diagram schematically illustrating an afterimage preventing apparatus of a plasma display panel according to another exemplary embodiment of the present invention. FIG. 12 is a block diagram schematically illustrating a logic controller in the apparatus for preventing afterimage occurrence of the plasma display panel of FIGS. 10 and 11.

Referring to the drawings, the afterimage prevention apparatuses 57 and 67 of the plasma display panel include a still image detection unit 571 and 671 in the afterimage prevention apparatus of the plasma display panel which prevents the afterimage generation of the plasma display panel. ; Afterimage generation prevention parts 572 and 672 are provided.

The still image detectors 571 and 671 detect whether the input image to be displayed on the screen is a still image. The afterimage prevention units 572 and 672 may repeatedly reduce or increase the brightness of the displayed image according to whether the input image is a still image to prevent generation of an afterimage.

The afterimage prevention units 572 and 672 include a still image determining unit 673 and a brightness adjusting unit 674. The still image determination unit 673 determines whether the input image is a still image. The brightness controller 674 adjusts the brightness of the displayed image according to whether the input image is a still image.

Here, the afterimage prevention apparatuses 57 and 67 of the plasma display panel are apparatuses for preventing the afterimage generation method of the plasma display panel shown in FIGS. 7 to 9, and the still image detecting unit 571 and 671 may be a still image. After the detection step, the afterimage prevention unit (572, 672) performs the afterimage prevention step, the still image determination unit 673 performs a still image determination step, the brightness adjustment unit 674 brightness adjustment step Perform

At this time, in the present embodiment to adjust the brightness of the screen, there may be a variety of methods for adjusting the brightness of the screen, in particular, it would be preferable to use a method for adjusting the number of sustain pulses per frame.

The afterimage prevention apparatuses 57 and 67 of the plasma display panel of the present invention may be included in a driving apparatus of a conventional plasma display panel. The driving apparatus of the plasma display panel may include an image processor 56 and 66 and a logic controller 52. 62, an address driver 53, an X driver 54, and a Y driver 55. At this time, in the driving device of the plasma display panel including the address voltage control devices 57 and 67 according to the present invention, the same components as those of the driving device of the conventional plasma display panel shown in FIG. Detailed descriptions thereof will be omitted.

The still image detectors 571 and 671 detect a still image by receiving an image signal from an external image signal processor of the image processor 56 and 66, and adjust the number of sustain pulses in the afterimage prevention unit 572 and 672. This may be input to the logic controllers 52 and 62 shown in FIG. 12 to adjust the number of sustain pulses.

In this case, as shown in FIG. 12, the still image detection signal may be externally input to the logic controllers 52 and 62 to adjust the number of sustain pulses through the microcontroller in the logic controller.

Each of the still image detecting units 571 and 671 and the afterimage preventing unit 572 and 672 according to the present invention may be configured to be included in a component of the driving apparatus of the plasma display panel. In particular, in the present exemplary embodiment, the still image detection units 571 and 671 are configured to be included in the image processing units 56 and 66, and the afterimage prevention units 572 and 672 are included in the logic controllers 52 and 62. It may be configured.

According to the method of preventing the afterimage generation of the plasma display panel according to the present invention, it is possible to prevent the occurrence of a permanent image sticking phenomenon that may occur when the still image is continued for a long time.

In addition, it is possible to faithfully display the luminance of the screen to be expressed while preventing generation of permanent afterimages due to still images.

Although the present invention has been described with reference to one embodiment shown in the accompanying drawings, it is merely an example, and those skilled in the art may realize various modifications and equivalent other embodiments therefrom. I can understand. Accordingly, the true scope of protection of the invention should be defined only by the appended claims.

1 is a perspective view showing an internal structure of a conventional three-electrode surface discharge plasma display panel.

FIG. 2 is a cross-sectional view illustrating a configuration of a unit display cell of the panel of FIG. 1.

3 is a block diagram illustrating a conventional driving device of the plasma display panel of FIG. 1.

4 is a timing diagram illustrating a conventional driving method of the plasma display panel of FIG. 1.

FIG. 5 is a timing diagram illustrating driving signals applied to electrode lines of the plasma display panel of FIG. 1 in a unit sub-field of FIG. 4.

6 is a graph schematically illustrating a method for preventing afterimage generation of a conventional plasma display panel.

7 is a flowchart schematically illustrating a method for preventing afterimage generation of a plasma display panel according to an exemplary embodiment of the present invention.

8 is a flowchart schematically illustrating a method for preventing afterimage generation of a plasma display panel according to another exemplary embodiment of the present invention.

FIG. 9 is a graph schematically illustrating a change in the number or brightness of sustain pulses over time by the method of preventing afterimage generation of the plasma display panel of FIGS. 7 and 8.

10 is a block diagram schematically illustrating an apparatus for preventing afterimage generation of a plasma display panel according to an exemplary embodiment of the present invention.

FIG. 11 is a block diagram schematically illustrating an afterimage preventing apparatus of a plasma display panel according to another exemplary embodiment of the present invention.

FIG. 12 is a block diagram schematically illustrating a logic controller in the apparatus for preventing afterimage occurrence of the plasma display panel of FIGS. 10 and 11.

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

22, 52: logic controller 23, 53: address driver

24, 54: X driver 25, 55: Y driver

26, 56: image processing unit 571, 671: still image detection unit

572, 672: Afterimage prevention unit 673: Still image determination unit

674: brightness control

Claims (16)

In the afterimage prevention method of the plasma display panel for preventing the afterimage generation of the plasma display panel, A still image detecting step of detecting whether the input image to be displayed on the screen is a still image; And a residual image prevention step of preventing the occurrence of an afterimage by repeatedly decreasing and increasing the brightness of the displayed image according to whether the input image is a still image. The method of claim 1, In the afterimage prevention step, When the input image is determined to be a still image by the detection in the still image sensing step, the afterimage prevention step is performed. When the input image is not a still image, the afterimage prevention step is not performed. Method of preventing afterimage generation of plasma display panel. The method of claim 1, The afterimage prevention step, A first step of decreasing the brightness of the displayed image from a first level to a second level, a second step of maintaining the brightness of the displayed image at a second level for a predetermined time, and brightness of the displayed image A third step of increasing from the second level to the first level, A method of preventing afterimage generation of a plasma display panel by repeating the first, second, and third steps. The method of claim 3, The steps of each of the first step, second step, and third step, A still image determination step of determining whether the input image is a still image, and a brightness adjustment step of adjusting the brightness of the displayed image according to whether the input image is a still image, the afterimage prevention of the plasma display panel Way. The method of claim 4, wherein In the afterimage prevention step, If it is determined that the input image is not a still image, the method of preventing afterimage generation of the plasma display panel is ended. Discharge cells are formed in an area where address electrode lines intersect with sustain electrode line pairs in which X electrode lines and Y electrode lines are alternately arranged side by side, and a frame as a display period between the X electrode lines and the Y electrode lines. In the method of preventing afterimage generation of the plasma display panel to display a screen corresponding to the input image by applying a predetermined number of sustain pulses every time, A still image detecting step of detecting whether the input image is a still image; And a residual image prevention step of preventing the occurrence of an afterimage by repeatedly reducing and increasing the number of sustain pulses per frame, depending on whether the input image is a still image. The method of claim 6, In the afterimage prevention step, When the input image is determined to be a still image by the detection in the still image sensing step, the afterimage prevention step is performed. When the input image is not a still image, the afterimage prevention step is not performed. Method of preventing afterimage generation of plasma display panel. The method of claim 6, The afterimage prevention step, A first step of reducing the number of sustain pulses per frame from a first level to a second level, a second step of maintaining the number of sustain pulses per frame at a second level for a period of time, and the sustain pulses per frame A third step of increasing the number of to from the second level to the first level, A method of preventing afterimage generation of a plasma display panel by repeating the first, second, and third steps. The method of claim 8, The steps of each of the first step, second step, and third step, Still image generation of the plasma display panel comprising a still image determination step of determining whether the input image is a still image, and a brightness adjustment step of adjusting the number of sustain pulses per frame according to whether the input image is a still image. Prevention method. The method of claim 9, In the afterimage prevention step, If it is determined that the input image is not a still image, the method of preventing afterimage generation of the plasma display panel is ended. In the afterimage prevention apparatus of the plasma display panel for preventing the afterimage generation of the plasma display panel, A still image detecting unit detecting whether the input image to be displayed on the screen is a still image; And a residual image generation prevention unit for repeatedly preventing the occurrence of an afterimage by repeatedly decreasing and increasing the brightness of the displayed image, depending on whether the input image is a still image. The method of claim 11, The afterimage prevention unit, The brightness of the displayed image is reduced from the first level to the second level, the brightness of the displayed image is maintained at the second level for a predetermined time, and the brightness of the displayed image is changed from the second level to the first level. An apparatus for preventing afterimage generation of a plasma display panel which is repeatedly performed to increase and decrease the brightness and increase of the displayed image. The method of claim 12, The afterimage prevention unit, Apparatus for preventing afterimage generation of a plasma display panel including a still image determining unit determining whether the input image is a still image and a brightness adjusting unit adjusting the brightness of the displayed image according to whether the input image is a still image. . Discharge cells are formed in an area where address electrode lines intersect with sustain electrode line pairs in which X electrode lines and Y electrode lines are alternately arranged side by side, and a frame as a display period between the X electrode lines and the Y electrode lines. In the after-image generation prevention device of the plasma display panel to display a screen corresponding to the input image by applying a predetermined number of sustain pulses every time, A still image detecting unit detecting whether the input image is a still image; And an afterimage prevention unit for repeating the reduction and increase of the number of sustain pulses per frame to prevent the occurrence of an afterimage, depending on whether the input image is a still image. The method of claim 14, The afterimage prevention unit, Reducing the number of sustain pulses per frame from a first level to a second level, maintaining the number of sustain pulses per frame at a second level for a period of time, and maintaining the number of sustain pulses per frame at a second level. An apparatus for preventing afterimage generation of a plasma display panel which repeats increasing to one level and repeats decreasing and increasing the number of sustain pulses per frame. The method of claim 15, The afterimage prevention unit, Prevention of after-image generation of the plasma display panel having a still image determination unit for determining whether the input image is a still image, and a brightness adjusting unit for adjusting the number of sustain pulses per frame according to whether the input image is a still image Device.