KR20050036605A - A method for displaying pictures on plasma display panel - Google Patents

Abstract

The present invention relates to an image display method of a plasma display panel that reduces pseudo contours. The present invention differs in the arrangement of subfields of odd lines and even lines in the horizontal direction on the plasma display panel. The subfield array of odd lines has a structure in which each subfield weight increases in ascending order, and the even field subfield weight has a structure in which each subfield weight decreases in descending order. That is, it is configured to have different subfield arrangements in the space of the plasma display panel. Through this, the average weight is constant in each subfield between each line, thereby reducing pseudo contours.

Description

Image display method of plasma display panel {A METHOD FOR DISPLAYING PICTURES ON PLASMA DISPLAY PANEL}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image display method of a plasma display panel (PDP), and more particularly to an image display method of a plasma display panel for reducing pseudo contours.

Recently, flat display devices such as a liquid crystal display (LCD), a field emission display (FED), and a plasma display panel have been actively developed. Among these flat panel display devices, the plasma display panel has advantages of higher luminance and luminous efficiency and wider viewing angle than other flat panel display devices. Therefore, the plasma display panel is in the spotlight as a display device to replace a conventional cathode ray tube (CRT) in a large display device of 40 inches or more.

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. The plasma display panel is classified into a direct current type and an alternating current type according to a shape of a driving voltage waveform applied and a structure of a discharge cell.

In the DC plasma display panel, the electrode is exposed without the discharge space insulated, so that the current flows in the discharge space while the voltage is applied, and there is a disadvantage in that a resistance for current limitation must be made. On the other hand, in the AC plasma display panel, since the electrode covers the dielectric layer, the current is limited by the formation of a natural capacitance component, and the electrode is protected from the impact of ions during discharge.

1 is a partial perspective view of an AC plasma display panel.

As shown in FIG. 1, the scan electrode 4 and the sustain electrode 5 covered with the dielectric layer 2 and the protective film 3 on the glass substrate 1 are formed in pairs in parallel. On the glass substrate 6, a plurality of address electrodes 8 covered with the insulator layer 7 are formed. The partition 9 is formed on the insulator layer 7 between the address electrodes 8 in parallel with the address electrode 8, and the phosphor 10 is formed on the surface of the insulator layer 7 and on both sides of the partition 9. Is formed. 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 at the intersection of the scan electrode 4 and the sustain electrode 5 paired with the address electrode 8 forms a discharge cell 12.

2 shows an electrode arrangement diagram of the plasma display panel.

As shown in FIG. 2, the electrodes of the plasma display panel are arranged in a matrix of m × n. Specifically, the address electrodes A1 -Am are arranged in the column direction and n rows of scan electrodes in the row direction ( Y1-Yn and sustain electrodes X1-Xn are arranged in a zigzag. The discharge cell 12 of FIG. 2 corresponds to the discharge cell 12 of FIG.

In general, the driving method of the AC plasma display panel includes a reset period, an addressing period, and a sustain period.

The reset period is a period of initializing the state of each cell in order to perform an addressing operation smoothly on the cell. The addressing period is an address voltage for a cell (addressed cell) turned on to select a cell that is turned on and a cell that is not turned on in a panel. It is a period of time to perform the operation of accumulating wall charge by applying a. The sustain period is a period in which a discharge is applied to actually display an image in the addressed cells by applying a sustain pulse.

As shown in FIG. 3, the plasma display panel divides one frame (1TV field) into a plurality of subfields, and time-division control them to implement gray scale. Each subfield consists of the reset period, the addressing period and the sustain period described above. 3 illustrates a case in which one frame is divided into eight subfields to implement 256 gray levels. Each subfield SF1-SF8 consists of a reset period (not shown), an address period A1-A8, and a sustain period S1-S8, and the sustain periods S1-S8 are light emission periods 1T, 2T. , 4T, ..., 128T) becomes 1: 2: 4: 8: 16: 32: 64: 128.

At this time, for example, in order to implement a gray scale of 3, the discharge cell is discharged in the subfield SF1 having the 1T light emission period and the subfield SF2 having the 2T light emission period so that the sum of the discharge periods is 3T. In this manner, 256 grayscale images are displayed by combining subfields having different light emission periods.

However, pseudo contours occur due to human visual characteristics when displaying moving images by the subfield method as described above. 4 is a diagram illustrating an example in which a pseudo contour occurs in detail. When the image having the gradation 127 and the gradation 128 side by side moves at a speed of 1 to the right, it may be represented as shown in FIG. 4 by the subfield arrangement as shown in FIG. 3. At this time, the human vision causes the gray level to be recognized in the direction of the arrow as shown in FIG. Therefore, a pseudo contour such as a gray scale 255 occurs between the gray scales 127 and 128.

FIG. 5 is a diagram illustrating a subfield on / off state of gradation 127 and gradation 128 in the conventional subfield arrangement as shown in FIG. 3. As shown in Fig. 5, in order to express gradation 127, the subfield weights 1 to 7 are turned on and the subfield weight 8 is turned off. In the case of representing the gradation 128, the subfield weights 1 to 7 are turned off and the subfield weight 8 is turned on. The gradation 127 and the gradation 128 differ only in gradation, but the on / off state of the subfield suddenly changes, which is a direct cause of the pseudo contour.

SUMMARY OF THE INVENTION The present invention has been made in an effort to provide an image display method of a plasma display panel, which is intended to solve the problems of the prior art as described above.

The image display method of the plasma display panel according to a feature of the present invention for achieving the above object

An image display method of a plasma display panel in which an image of each frame displayed on a plasma display panel corresponding to an input video signal is divided into a plurality of subfields, and a gray level is displayed by combining luminance weights of the plurality of subfields.

(a) applying data corresponding to the input image signal to a first horizontal line group on the plasma display panel by a first subfield luminance weight array;

(b) the second horizontal line group, which is a line adjacent to each line belonging to the first line group, by the second subfield luminance weighting arrangement having the first subfield luminance weighting arrangement and the luminance weight in the reverse order; And applying data corresponding to the video signal.

The first line group is an odd line on the plasma display panel, and the second line group is an even line on the plasma display panel.

In addition, each subfield weight of the first subfield luminance weights array increases in ascending order, and each subfield weight of the second subfield luminance weights array decreases in descending order.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement 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 the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention. Like parts are designated by like reference numerals throughout the specification.

An image display method of a plasma display panel according to an embodiment of the present invention will now be described in detail with reference to the drawings.

FIG. 6 is a diagram illustrating a subfield structure of an image display method of a plasma display panel according to an exemplary embodiment of the present invention. FIG. 6A is a subfield weight structure applied to odd lines on a plasma display panel. FIG. 3 is a diagram illustrating a subfield weight structure applied to even lines on a display panel. FIG. In this case, the odd lines and the even lines mean lines in the male direction (that is, the row direction) of each discharge cell on the plasma display panel shown in FIG.

As shown in FIG. 6A, the subfield weight structure of odd lines on the plasma display panel increases in ascending order to 1, 2, 4, 8, 16, 32, 64, and 128. That is, the subfield weighting structure increases in ascending order for one frame of the input video signal until one frame passes time.

However, as shown in FIG. 6B, the subfield weight structure of even lines on the plasma display panel is in descending order of 128, 64, 32, 16, 8, 4, 2, and 1 as opposed to the odd odd lines shown in FIG. 6A. Decreases.

That is, the subfield weighting structure of odd lines and the subfield weighting structure of even lines are reversed to each other, so that the subfield weighting structure of odd lines increases in ascending order and the subfield weighting structure of even lines decreases in descending order. Has a structure.

Here, as shown in FIGS. 6A and 6B, the subfield weights may be slightly changed in the ascending and descending order of the subfield weights of the odd and even lines. That is, the subfield weight itself may be somewhat modified by those skilled in the art to which the subfield structures of odd and even lines are different.

6A and 6B show a subfield weighting structure in which odd lines increase in ascending order, and even lines decrease in descending order. On the contrary, odd lines decrease in descending order and even lines increase in ascending order. It may have a subfield weighting structure. Hereinafter, for convenience, only the subfield weighting structure in which odd lines increase in ascending order and even lines decrease in descending order will be described.

7A and 7B show an on / off state and an angle when the gray level 127 and the gray level 128 are odd and even lines in the subfield structure of the image display method of the plasma display panel according to the embodiment of the present invention shown in FIG. It is a figure which shows the weight difference between subfields.

As shown in FIG. 7A, in the on / off state of each subfield of an odd line on the plasma display panel, weight differences between the subfields are +1, +2, +4, +8, +16, +32, and +64. It can be seen that. In addition, as shown in FIG. 7B, the weight difference between each subfield in the on / off state of each subfield of an even line on the plasma display panel is -64, -32, -16, -8, -4, -2,- It can be seen that 1. At this time, it can be seen that the subfield weight difference between each subfield of the odd line and the subfield weight between each subfield of the even line compensate each other. That is, by inverting the subfield weighting structures of odd and even lines in space, pseudo contours are reduced by compensating a weight difference between each subfield in odd lines in the next even line.

FIG. 8 is a diagram illustrating an average of subfield weights between odd lines and even lines in one frame when subfield weight structures of odd lines and even lines are reversed as in the embodiment of the present invention. That is, when the subfield weights of odd lines increase in ascending order and the subfield weights of even lines decrease in descending order, this indicates the average value of the subfield weights between odd lines and even lines. As shown in FIG. 8, the average subfield weight between odd lines and even lines is flattened to reduce pseudo contours.

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, by arranging the subfield weights of the odd and even lines in the space of the plasma display panel differently, the weight of each subfield between the odd and even lines is flattened to reduce pseudo contours. There are unique effects that can be made.

1 is a partial perspective view of an AC plasma display panel.

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

3 is a diagram illustrating a gray scale display method of a plasma display panel.

4 is a diagram illustrating an example in which a pseudo contour occurs.

FIG. 5 is a diagram illustrating an on / off state of each subfield of gradation 127 and gradation 128 in the conventional subfield arrangement as shown in FIG. 3.

6 is a diagram illustrating a subfield structure of an image display method of a plasma display panel according to an exemplary embodiment of the present invention. FIG. 6A is a subfield weighting structure applied to odd lines on a plasma display panel, and FIG. 6B is a diagram on a plasma display panel. It is a figure which shows the subfield weight structure applied to an even line.

7A and 7B show an on / off state when the gray level 127 and the gray level 128 are odd and even lines in the subfield structure of the image display method of the plasma display panel according to the embodiment of the present invention shown in FIG. It is a figure which shows the weight difference between each subfield.

FIG. 8 is a diagram illustrating an average of subfield weights between odd lines and even lines in one frame when subfield weight structures of odd lines and even lines are reversed as in the embodiment of the present invention.

Claims (4)

An image display method of a plasma display panel in which an image of each frame displayed on a plasma display panel corresponding to an input video signal is divided into a plurality of subfields, and a gray level is displayed by combining luminance weights of the plurality of subfields. (a) applying data corresponding to the input image signal to a first horizontal line group on the plasma display panel by a first subfield luminance weight array; (b) the second horizontal line group, which is a line adjacent to each line belonging to the first line group, by the second subfield luminance weighting arrangement having the first subfield luminance weighting arrangement and the luminance weight in the reverse order; And applying data corresponding to an image signal. The method of claim 1, And wherein the first line group is an odd line on the plasma display panel, and the second line group is an even line on the plasma display panel. The method according to claim 1 or 2, And each subfield weight of the first subfield luminance weight array is increased in ascending order, and each subfield weight of the second subfield luminance weight array is decreased in descending order. The method according to claim 1 or 2, And each subfield weight of the first subfield brightness weight array is decreased in descending order, and each subfield weight of the second subfield brightness weight array is increased in ascending order.