KR20080062334A - Plasma display panel - Google Patents

Abstract

A plasma display panel is provided to lower panel reflectivity with a shading effect by relatively expanding an interval between a first black layer or a second black layer and a barrier rib. A first electrode(102) and a second electrode(103) are arranged in parallel on a front substrate(101). A first black layer(106) is arranged between the front substrate and the first electrode. The first black layer has a color darker than that of the first electrode. A second black layer(107) is arranged between the front substrate and the second electrode. The second black layer has a color darker than that of the second electrode. A rear substrate(111) is arranged to be opposite to the front substrate. A barrier rib(112) divides discharge cells between the front substrate and the rear substrate. One of the first black layer and second black layer is adjacent to the barrier rib and the remaining is arranged at a predetermined interval from the barrier rib.

Description

Plasma Display Panel

1A to 1B are views for explaining the structure of a plasma display panel according to an embodiment of the present invention.

2A to 2B are views for explaining the first and second black layers in more detail.

3A to 3C are diagrams for explaining the reason for relatively widening the distance between the first black layer or the second black layer and the partition wall.

4 is a graph showing reflectance of a plasma display panel according to an embodiment of the present invention;

FIG. 5 is a diagram for explaining a case where a fourth black layer is disposed above the partition wall. FIG.

6 is a view for explaining another example of the first black layer and the second black layer in more detail.

FIG. 7 is a diagram for describing an image frame for implementing gray levels of an image in a plasma display panel according to an embodiment of the present invention. FIG.

8 is a view for explaining an example of an operation of a plasma display panel according to an embodiment of the present invention in a subfield included in an image frame;

FIG. 9 is a diagram for explaining another example of a rising ramp signal and a falling ramp signal. FIG.

10 is a diagram for explaining a pre-reset period.

11 is a diagram for explaining another type of a sustain signal.

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

101: front substrate 102: first electrode

103: second electrode 104: upper dielectric layer

105: protective layer 111: back substrate

112: partition wall 113: third electrode

114: phosphor layer 115: lower dielectric layer

112a: second partition 112b: first partition

102a and 130a: transparent electrode 102b and 103b: bus electrode

106: first black layer 107: second black layer

The present invention relates to a plasma display panel.

In general, a phosphor layer is formed in a discharge cell (Cell) partitioned by a partition, and a plurality of electrodes are formed in the plasma display panel. The drive signal is supplied to this electrode.

Then, the discharge is generated by the drive signal supplied in the discharge cell. When discharged by a drive signal in the discharge cell, the discharge gas filled in the discharge cell generates vacuum ultraviolet rays, and the vacuum ultraviolet light emits phosphors formed in the discharge cell to generate visible light. . The visible light displays an image on the screen of the plasma display panel.

One object of the present invention is to provide a plasma display panel which reduces panel reflectance to improve contrast characteristics of an image.

A plasma display panel according to an embodiment of the present invention for achieving the above object is a front substrate on which the first electrode and the second electrode are parallel to each other, and disposed between the front substrate and the first electrode and than the color of the first electrode A first black layer having a darker color, a second black layer disposed between the front substrate and the second electrode and having a color darker than that of the second electrode, and a back substrate and the front substrate disposed opposite the front substrate. A partition wall that partitions the discharge cell between the substrate and the rear substrate, wherein one of the first black layer and the second black layer is disposed at a position adjacent to the partition wall, and the other is disposed at a position spaced apart from the partition wall by a predetermined distance. .

In addition, the first electrode is an electrode to which a scan signal is supplied in an address period of a subfield, the first black layer is disposed at a position spaced apart from the barrier rib by a predetermined distance, and the second black layer is positioned at a position adjacent to the barrier rib. Is placed.

Further, the distance between the first black layer and the second black layer is 0.7 to 2.5 times the distance between the partition and either the first black layer or the second black layer disposed at a position adjacent to the partition.

Further, the distance between the first black layer and the second black layer is 0.7 times or more and two times or less the distance between the partition and either the first black layer or the second black layer disposed at a position adjacent to the partition.

In addition, the space | interval between a 1st black layer and a 2nd black layer is 0.8 times or more and 1.8 times or less of the space | interval between any one of a 1st black layer or a 2nd black layer arrange | positioned adjacent to a partition and a partition.

In addition, a third black layer having a color darker than a color of at least one of the first electrode and the second electrode is further formed at a position corresponding to the partition wall.

Further, the spacing between the third black layer and either the first black layer or the second black layer is substantially the same as the spacing between the partition and either the first black layer or the second black layer.

Further, a fourth black layer having a color darker than the color of the partition is further formed on the partition.

Further, the spacing between the fourth black layer and either the first black layer or the second black layer is substantially the same as the spacing between the partition and either the first black layer or the second black layer.

In addition, the first electrode and the second electrode include a transparent electrode and a bus electrode, and the first black layer and the second black layer are disposed between the transparent electrode and the bus electrode.

Further, the spacing between the first black layer and the second black layer is substantially equal to the spacing between any one of the first black layer or the second black layer disposed at a position adjacent to the partition wall.

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

1A to 1B are views for explaining the structure of a plasma display panel according to an embodiment of the present invention.

First, referring to FIG. 1A, a plasma display panel according to an embodiment of the present invention may include a front substrate 101 on which first electrodes 102 and Y and second electrodes 103 and Z which are parallel to each other are disposed. The back substrate 111 on which the third electrodes 113 and X intersect with the electrode 102 and the second electrode 103 are disposed is bonded.

The first electrode 102 and the second electrode 103 may include transparent electrodes 102a and 103a and bus electrodes 102b and 103b, respectively.

The transparent electrodes 102a and 103a may include a transparent material such as indium tin oxide (ITO).

The bus electrodes 102b and 103b may include a metal material having excellent electrical conductivity, such as silver (Ag).

Here, the first black layer 106 is disposed between the front substrate 101 and the first electrode 102, and the second black layer 107 is disposed between the front substrate 101 and the second electrode 103. This is placed.

For example, the transparent electrode 102a of the first electrode 102 when the first electrode 102 and the second electrode 103 include the transparent electrodes 102a and 103a and the bus electrodes 102b and 103b, respectively. ) And the first black layer 106 is disposed between the bus electrode 102b and the second black layer 107 is disposed between the transparent electrode 103a of the second electrode 103 and the bus electrode 103b. Is placed.

Here, the first black layer 106 has a darker color than the color of the first electrode 102, and the second black layer 107 has a darker color than the color of the second electrode 103. The first black layer 106 and the second black layer 107 may be formed of substantially the same material. For example, the first black layer 106 and the second black layer 107 may include ruthenium (Ru).

The first black layer 106 and the second black layer 107 prevent the light incident from the outside from being reflected by the first electrode 102 and the second electrode 103.

The first black layer 106 and the second black layer 107 will be described in more detail later.

A dielectric layer covering the first electrode 102 and the second electrode 103 and Z on the front substrate 101 on which the first electrode 102 and the second electrode 103 and Z are formed, for example Upper dielectric layer 104 may be disposed.

This upper dielectric layer 104 limits the discharge current of the first electrode 102, Y and the second electrode 103, Z and between the first electrode 102, Y and the second electrode 103, Z. Can be insulated.

A protective layer 105 may be disposed on the upper surface of the upper dielectric layer 104 to facilitate a discharge condition. The protective layer 105 may be formed of a material having a high secondary electron emission coefficient, such as magnesium oxide (MgO).

Meanwhile, in FIG. 1A, when the first electrode 102 and the second electrode 103 each have a plurality of layer structures, for example, the transparent electrodes 102a and 103a and the bus electrodes 102b and 103b are included. Although only the case is described, the first electrode 102 and the second electrode 103 may have a single layer structure.

For example, as shown in FIG. 1B, the first electrode 102 and the second electrode 103 each have a single layer structure, and a first black layer (between the first electrode 102 and the front substrate 101). 106 may be disposed, and a second black layer 107 may be disposed between the second electrode 103 and the front substrate 101.

Meanwhile, electrodes, for example, third electrodes 113 and X are disposed on the rear substrate 111, and third electrodes 113 and X are disposed on the rear substrate 111 on which the third electrodes 113 and X are formed. A dielectric layer overlying, for example, lower dielectric layer 115 may be disposed. The lower dielectric layer 115 may insulate the third electrodes 113 and X.

On top of the lower dielectric layer 115, a discharge space, that is, a partition wall 112 such as a stripe type, a well type, a delta type, and a honeycomb type for partitioning the discharge cells is formed. Can be arranged. Accordingly, red (R), green (G), and blue (B) discharge cells may be provided between the front substrate 101 and the rear substrate 111.

In addition to the red (R), green (G), and blue (B) discharge cells, a white (W) or yellow (Y) discharge cell may be further provided.

Meanwhile, although the widths of the red (R), green (G), and blue (B) discharge cells in the plasma display panel according to an embodiment of the present invention may be substantially the same, red (R) and green (G) may be substantially the same. And the width of at least one of the blue (B) discharge cells may be different from that of the other discharge cells.

For example, the width of the red (R) discharge cell is the smallest, and the width of the green (G) and blue (B) discharge cells can be made larger than the width of the red (R) discharge cell.

Here, the width of the green (G) discharge cell may be substantially the same as or different from the width of the blue (B) discharge cell.

In this case, the width of the phosphor layer 114 to be described later disposed in the discharge cell is also changed in relation to the width of the discharge cell. For example, the width of the blue (B) phosphor layer disposed in the blue (B) discharge cell is wider than the width of the red (R) phosphor layer disposed in the red (R) discharge cell, and at the same time in the green (G) discharge cell. The width of the green (G) phosphor layer disposed may be wider than the width of the red (R) phosphor layer disposed in the red (R) discharge cell.

Then, color temperature characteristics of the image to be implemented may be improved.

In addition, the plasma display panel according to the exemplary embodiment of the present invention may have not only the structure of the partition wall 112 shown in FIG. 1A but also the structure of the partition wall having various shapes. For example, the partition wall 112 includes a first partition wall 112b and a second partition wall 112a, where the height of the first partition wall 112b and the height of the second partition wall 112a are different from each other. At least one of the first partition wall 112b or the second partition wall 112a, and a channel type partition wall structure having a channel usable as an exhaust passage, at least one of the first partition wall 112b and the second partition wall 112a. Grooved partition wall structure having a groove formed in the groove will be possible.

Here, in the case of the differential partition wall structure, the height of the first partition wall 112b among the first partition wall 112b or the second partition wall 112a may be lower than the height of the second partition wall 112a. In addition, in the case of the channel-type partition wall structure, a channel may be provided in the first partition wall 112b.

On the other hand, in the plasma display panel according to an embodiment of the present invention, although the red (R), green (G), and blue (B) discharge cells are shown and described as being arranged on the same line, they may be arranged in different shapes. It will be possible. For example, a delta type arrangement in which red (R), green (G) and blue (B) discharge cells are arranged in a triangular shape may be possible. In addition, the shape of the discharge cell may also be a variety of polygonal shapes, such as pentagonal, hexagonal, as well as rectangular.

In addition, in FIG. 1A, only the case where the partition wall 112 is disposed on the rear substrate 111 is illustrated, but the partition wall 112 may be disposed on at least one of the front substrate 101 and the rear substrate 111. .

A predetermined discharge gas may be filled in the discharge cell partitioned by the partition wall 112. Preferably, the discharge gas containing xenon (Xe) is filled, where the content of xenon (Xe) may be advantageously 10% or more relative to the mass of the total discharge gas in order to improve the discharge efficiency.

In addition, a phosphor layer 114 that emits visible light for image display may be disposed in the discharge cell partitioned by the partition wall 112. For example, red (R), green (G), and blue (B) phosphor layers may be disposed.

In addition to the red (R), green (G), and blue (B) phosphors, a white (W) and / or yellow (Y) phosphor layer may be further disposed.

In addition, the thickness of the phosphor layer 114 in at least one of the red (R), green (G), and blue (B) discharge cells may be different from other discharge cells. For example, the thickness of the phosphor layer of the green (G) discharge cell, ie the phosphor layer in the green (G) phosphor layer or the blue (B) discharge cell, ie the blue (B) phosphor layer, is It may be thicker than the thickness of the phosphor layer, ie the red (R) phosphor layer. Here, the thickness of the green (G) phosphor layer may be substantially the same as or different from the thickness of the blue (B) phosphor layer.

In the above description, only one example of the plasma display panel according to an exemplary embodiment of the present invention is illustrated and described. However, the present invention is not limited to the plasma display panel having the above-described structure. For example, the description hereinabove illustrates only the case where the top dielectric layer number 104 and the bottom dielectric layer number 115 are each one layer, but one or more of these top dielectric layers and bottom dielectric layers may be a plurality of layers. It can also be layered.

In addition, the width or thickness of the third electrode 113 formed on the rear substrate 111 may be substantially constant, but the width or thickness inside the discharge cell may be different from the width or thickness outside the discharge cell. will be. For example, the width or thickness inside the discharge cell may be wider or thicker than that outside the discharge cell.

Next, FIGS. 2A to 2B are diagrams for describing the first and second black layers in more detail.

2A to 2B, one of the first black layer 106 or the second black layer 107 is disposed at a position adjacent to the partition wall 112, and the other is spaced apart from the partition wall 112 by a predetermined distance. Is placed in the position.

For example, as shown in FIG. 2A, the first black layer 106 is disposed at a position spaced apart from the partition wall 112 by G1, and the second black layer 107 is disposed at a position adjacent to the partition wall 112. The first black layer 106 and the second black layer 107 are disposed spaced apart by G2.

In order to arrange the first black layer 106 and the second black layer 107 in this manner, the first electrode 102 is disposed at a position spaced apart from the partition wall 112 by a predetermined distance, and the second electrode 103 is disposed. May be disposed at a position adjacent to the partition wall 112.

In addition, when the first electrode 102 and the second electrode 103 include the transparent electrodes 102a and 103a and the bus electrodes 102b and 103b, the first black layer 106 is the first electrode 102. The second black layer 107 may be disposed on the transparent electrode 102a of the c) in the direction of the center of the discharge cell, and the second black layer 107 may be disposed on the transparent electrode 103a of the second electrode 103 in the direction of the partition wall 112.

Here, the first electrode 102 corresponding to the first black layer 106 disposed at a position spaced apart from the partition 112 by G1 is an electrode to which a scan signal is supplied in an address period of a subfield.

As such, when the first electrode 102 to which the scan signal is supplied is disposed in the center portion of the discharge cell relative to the second electrode 103, the address discharge generated by the scan signal is further stabilized to improve driving efficiency. May be advantageous.

Here, the distance G1 between the first black layer 106 and the partition wall 112 is set relatively wide. Preferably, the gap G2 between the first black layer 106 and the second black layer 107 is the first black layer 106 or the second black layer 107 disposed at a position adjacent to the partition wall 112. ), That is, 0.7 times or more and 2.5 times or less of the interval G1 between the first black layer 106 and the partition wall 112. That is, 0.7G1 ≦ G2 ≦ 2.5G1.

Here, in FIG. 2A, the shortest gap G1 between the first black layer 106 and the partition wall 112 is set as the shortest gap between the first black layer 106 and the upper portion of the partition wall 112, but differently It is also possible to set the shortest gap between the first black layer 106 and the lower portion of the partition wall 112 to the shortest gap G1 between the first black layer 106 and the partition wall 112.

Here, the gap G1 between the partition wall 112 and the first black layer 106 and the gap G2 between the first black layer 106 and the second black layer 107 may be substantially the same.

In addition, the front substrate 101 includes third black layers 200 and 210 having a color darker than at least one of the first electrode 102 and the second electrode 103 at a position corresponding to the partition wall 112. Can be further formed.

In this case, the spacing G1 between the partition wall 112 and the first black layer 106 may be substantially equal to the spacing G1 ′ between the third black layer and the first black layer 106 of number 200. have. That is, the gap G1 between the partition wall 112 and the first black layer 106 may be defined as the gap G1 ′ between the third black layer 106 and the first black layer 106.

Accordingly, the relationship of 0.7G1 '≦ G2 ≦ 2.5G1 ′ may also be established.

Here, the widths of the third black layers 200 and 210 may be substantially the same as the upper or lower widths of the partition walls 112, or in consideration of an error in the manufacturing process. The width may be greater than or equal to about 10 μm and less than or equal to 40 μm than the width of the partition 112.

On the other hand, when the length S2 between the first electrode 102 and the second electrode 103 is excessively large, the discharge voltage between the first electrode 102 and the second electrode 103 is reduced. It may be excessively high, and thus driving efficiency may decrease.

In addition, when the length S2 between the first electrode 102 and the second electrode 103 is excessively large, since the positive column may not be sufficiently utilized during discharge, luminance may be lowered.

In consideration of this, it may be advantageous that the length S2 between the first electrode 102 and the second electrode 103 is 80 μm or more, preferably 90 μm or more.

On the other hand, the widths of the first electrode 102 and the second electrode 103, for example, the widths W1 and W2 of the transparent electrodes 102a and 103a of the first electrode 102 and the second electrode 103 are excessively excessive. In the case of a large distance, the distance S2 between the first electrode 102 and the second electrode 103 may be excessively shortened, and thus the luminance may be lowered because the positive light column region cannot be sufficiently utilized during discharge. .

In addition, the widths of the first electrode 102 and the second electrode 103, for example, the widths W1 and W2 of the transparent electrodes 102a and 103a of the first electrode 102 and the second electrode 103 are excessively made. If the size is small, the electric resistance values of the first electrode 102 and the second electrode 103 are large, and thus driving efficiency may decrease.

In view of this, the widths of the first electrode 102 and the second electrode 103, for example, the widths W1 and W2 of the transparent electrodes 102a and 103a of the first electrode 102 and the second electrode 103 are It is preferable that the length S1 of the discharge cell, for example, 60% or more and 90% or less of the distance S1 between two adjacent partition walls 112 parallel to the first electrode 102 and the second electrode 103.

Next, referring to FIG. 2B, unlike the case of FIG. 2A, the second black layer 107 is disposed at a position spaced apart from the partition wall 112 by G3, and the first black layer 106 is adjacent to the partition wall 112. It is arranged in a position to. The second black layer 107 and the first black layer 106 may be spaced apart by G4.

As shown in FIG. 2A, the gap G1 between the partition wall 112 and the first black layer 106 is relatively widened, or as shown in FIG. 2B, between the partition wall 112 and the second black layer 107. The reason why the interval G3 is relatively wide will be described with reference to FIGS. 3A to 3C and FIG. 4.

3A to 3C are diagrams for explaining the reason for relatively widening the distance between the first black layer or the second black layer and the partition wall.

4 is a graph showing the reflectance of the plasma display panel according to an embodiment of the present invention.

First, referring to FIG. 3A, a case where the first black layer 300 or the second black layer 310 and the partition 312 overlap each other in the region of d1 or d2 is different from one embodiment of the present invention.

In this case, the third black layers 320 and 330 and the first black layer 300 or the second black layer 310 which are formed at a specific position of the front substrate 301 to correspond to the partition 312 are adjacent to each other. Can be arranged.

In this structure, assume that light is obliquely incident from the outside to the panel as shown in FIG. 3B. In addition, suppose that the viewer watches an image from the front of the panel.

Some of the light incident at an angle to the panel is shielded by the unnumbered first black layer, the second black layer and the third black layer, so that a part of the discharge cells is divided into the first black layer, the second black layer and the first black layer. 3 will be obscured by the shadows caused by the black layer.

However, since the first black layer and the third black layer or the second black layer and the third black layer are disposed adjacent to each other, in the region of W as shown here in FIG. 3B, light incident from the outside will be reflected.

As a result, the light reflected from the W region is visible to the viewer, which may deteriorate the contrast characteristic of the image displayed on the panel.

The problem is that the first black layer 300 or the second black layer 310 and the partition 312 do not overlap and the first black layer 300 or the second black layer 310 and the partition 312 are adjacent to each other. It happens even if

On the other hand, when the spacing between the first black layer and the partition wall or the spacing between the second black layer and the partition wall is relatively wide as in one embodiment of the present invention, as shown in FIG. Shielded by a black layer 106, a second black layer 107, or a third black layer 200, 210.

For example, as shown in FIG. 2A, the first black layer 106 is disposed at a position spaced apart from the partition wall 112, and the second black layer 107 is disposed at a position adjacent to the partition wall 112. The first black layer 106, the second black layer 107, or the third black layer 200, 210 because the gap between the first black layer 106 and the third black layer of the number 200 is sufficiently wide. Most of the area of the discharge cell will be covered by the shadow generated by the shadow. This is called the Eclipse effect.

Accordingly, even when the viewer views the image displayed on the panel in front of the panel, the intensity of the reflected light seen by the viewer may be weaker than in the case of FIGS. 3A to 3B. Accordingly, the contrast characteristic of the image displayed on the panel can be improved.

In addition, suppose that the length L of the discharge cell, more specifically, the length L of the discharge cell in a direction crossing the first black layer 106 and the second black layer 107 is relatively small.

In this case, when the first black layer 106 and the second black layer 107 are disposed together at a position spaced apart from the partition 112, that is, the first black layer 106 and the second black layer 107 together When placed in the center portion of the discharge cell, the aperture ratio can be excessively reduced. In addition, as the ratio of the first black layer 106 and the second black layer 107 to cover the center portion of the discharge cell where the amount of light is slightly concentrated during driving increases, the luminance of the image may be drastically reduced.

On the other hand, as shown in FIG. 3C, either the first black layer 106 or the second black layer 107 is disposed at a position spaced apart from the partition wall 112, and the other is adjacent to the partition wall 112. This arrangement prevents the panel's aperture ratio from being excessively prevented even when the discharge cell length L is relatively small, and it is more advantageous to maintain the brightness sufficiently high and to lower the panel reflectance, thereby improving the contrast characteristic of the image. Can be.

The data for this is shown in FIG. 4.

Referring to FIG. 4, when the value of G2 / G1 has a value between 0.3 and 0.5, that is, the distance G2 between the first black layer and the second black layer in the previous FIG. 2A is the first black layer and the partition (or number). If the value is between 0.3 times and 0.5 times the distance G1 between the third black layers of 200), the area covered by the shadows generated by the first black layer and the second black layer is the right portion of the discharge cell, That is, it is known that the panel reflectance is 27% or more and 28% or less since the second electrode is biased and the left part of the discharge cell, that is, the part where the first electrode is disposed, is exposed.

This is because if the value of G4 / G3 has a value between 0.3 and 0.5, i.e. the distance G4 between the first black layer and the second black layer in Fig. 2b is equal to the second black layer and the partition (or the third black of number 210) The same applies to the case of having a value between 0.3 times and 0.5 times the distance G3 between layers).

In addition, when the value of G2 / G1 is 3.0 times or more, the area covered by the shadow generated by the first black layer and the second black layer is biased in the left part of the discharge cell, that is, the part in which the first electrode is disposed. The panel reflectance is rapidly increased to approximately 30% or more by exposing the right portion of the discharge cell, that is, the portion where the second electrode is disposed.

This is substantially the same even when the value of G4 / G3 is 3.0 times or more.

On the other hand, it can be seen that the panel reflectance is stable to approximately 18% or more and 22% or less in the range of G2 / G1 value or G4 / G3 value of 0.7 or more and 2.5 or less. This is due to the shading effect as described in detail above in FIG. 3C.

In consideration of the panel reflectance data described above, the gaps G2 and G4 between the first black layer and the second black layer are defined as either the first black layer or the second black layer disposed at a position adjacent to the partition wall. 0.7 times or more and 2.5 times or less of the intervals G1 and G3 therebetween may be advantageous to lower the panel reflectance to improve the contrast characteristics.

Further, the gaps G2 and G4 between the first black layer and the second black layer are the gaps G1 and G3 between any one of the first black layer or the second black layer disposed at a position adjacent to the partition wall. It may be more advantageous to improve the contrast characteristics by lowering the panel reflectance.

Next, FIG. 5 is a figure for explaining the case where a 4th black layer is arrange | positioned above a partition.

Referring to FIG. 5, fourth black layers 500 and 510 having a color darker than that of the partition wall 512 may be further disposed on the partition wall 512.

For example, the bulkhead 512 may include the fourth black layers 500 and 510 to replace the role of the third black layer, which is omitted, and omits the third black layers 200 and 210 of FIGS. 2A to 2B. Will be placed on top of the.

In this case, either the first black layer 506 or the second black layer 507 is disposed at a position adjacent to the fourth black layer 500, 510, and the other one is the fourth black layer 500, 510. It may be disposed at a position spaced apart from).

In addition, an interval between any one of the fourth black layers 500 and 510 and the first black layer 506 or the second black layer 507, for example, the fourth black layer and the first black layer ( The spacing G5 between the 506 may be substantially the same as the spacing between the partition 512 and the first black layer 506 as described above in detail. That is, the gap between the partition wall 512 and the first black layer 506 may be defined as the gap G4 between the fourth black layer of number 500.

Even in this case, as shown in FIG. 5, the distance G5 between the fourth black layer 506 and the first black layer 506 is maintained relatively wide, thereby obtaining the shading effect described above.

Accordingly, even when the third black layer to be disposed on the front substrate is replaced with the fourth black layer, as shown in FIG. 5, the panel reflectance may be reduced to improve the contrast characteristics of the image displayed on the panel.

Next, FIG. 6 is a view for explaining another example of the first black layer and the second black layer in more detail. Here, in FIG. 6, the description thereof will be omitted.

Referring to FIG. 6 (a), as described above, the first black layer 106 is disposed between the front substrate 101 and the first electrode 102, and the front substrate 101 and the second electrode 103 are disposed. The case where the 2nd black layer 107 is arrange | positioned between () is shown.

Here, the first electrode 102 and the first black layer 106 may be integrated, and the second electrode 103 and the second black layer 106 may be integrated.

For example, as shown in (a), the first electrode 102 and the second electrode 103 each include the transparent electrodes 102a and 103a and the bus electrodes 102b and 103b, respectively. The first black layer 106 is disposed between the transparent electrode 102a and the bus electrode 102b, and the second black layer is disposed between the transparent electrode 103a and the bus electrode 103b of the second electrode 103. Assume 107 is deployed. In this case, it is also possible to integrate the transparent electrodes 102a and 103a and the bus electrodes 102b and 103b to form the black electrodes 602b and 603b as shown in (b).

The black electrodes 602b and 603b may be formed of a material in which an electrode material and a black material having a color darker than that of the electrode material are mixed.

The black electrodes 602b and 603b may replace the first and second black layers described above in detail.

As such, when the black electrodes 602b and 602b are formed, the manufacturing cost can be reduced by reducing the number of manufacturing steps and the time required for the manufacturing steps.

Next, FIG. 7 is a diagram for describing an image frame for implementing gray levels of an image in a plasma display panel according to an exemplary embodiment of the present invention.

Referring to FIG. 7, an image frame for implementing gray levels of an image in a plasma display panel according to an exemplary embodiment of the present invention may be divided into a plurality of subfields having different emission counts.

Although not shown, one or more subfields among the plurality of subfields may be grayed out according to a reset period for initializing discharge cells, an address period for selecting discharge cells to be discharged, and the number of discharges. It can be divided into the sustain period to implement.

For example, when an image is to be displayed in 256 gray scales, for example, one image frame is divided into eight subfields SF1 to SF8 as shown in FIG. 7, and each of the eight subfields SF1 to SF8, respectively. Can be subdivided into a reset period, an address period and a sustain period.

The gray scale weight of the corresponding subfield may be set by adjusting the number of the sustain signals 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 described above, the number of sustain signals supplied in the sustain period of each subfield is adjusted according to the gray scale weight in each subfield, thereby implementing gray levels of various images.

The plasma display panel according to an embodiment of the present invention uses a plurality of image frames to implement an image, for example, to display an image of 1 second. For example, 60 image frames are used to display an image of 1 second. In this case, the length T of one image frame may be 1/60 second, that is, 16.67 ms.

In FIG. 7, only one image frame includes eight subfields. However, the number of subfields constituting one image frame may be variously changed. For example, one video frame may be configured with 12 subfields from the first subfield to the twelfth subfield, or one video frame may be configured with 10 subfields.

In addition, in FIG. 7, subfields are arranged in an order of increasing magnitude of gray scale weight in one image frame. Alternatively, subfields may be arranged in order of decreasing gray scale weight in one image frame. Alternatively, subfields may be arranged regardless of the gray scale weight.

Next, FIG. 8 is a diagram for explaining an example of an operation of a plasma display panel according to an embodiment of the present invention in a subfield included in an image frame.

Referring to FIG. 8, in the set-up period of the reset period for initialization, the voltage rises from the first voltage V1 to the second voltage V2 with the first electrode and then from the second voltage V2 to the third voltage. A ramp-up signal is supplied in which the voltage gradually rises to V3. Here, the first voltage V1 may be a voltage of the ground level GND.

In this setup period, a weak dark discharge, that is, setup discharge, occurs in the discharge cell by the rising ramp signal. By this setup discharge, some wall charges may accumulate in the discharge cell.

In a set-down period after the setup period, a ramp-down signal in a direction opposite to that of the ramp ramp signal is supplied to the first electrode after the ramp ramp signal.

Here, the falling ramp signal may gradually fall from the peak voltage of the rising ramp signal, that is, the fourth voltage V4 lower than the third voltage V3 to the fifth voltage V5.

As the falling ramp signal is supplied, a weak erase discharge, that is, a setdown discharge, occurs in the discharge cell. By this set-down discharge, wall charges such that address discharge can be stably generated in the discharge cells remain uniformly.

The shape of the rising ramp signal or the falling ramp signal described above may be variously changed. This will be described with reference to FIG. 9 attached thereto.

9 is a diagram for explaining another example of the rising ramp signal and the falling ramp signal.

Referring to FIG. 9, the falling ramp signal may gradually descend from the seventh voltage V7 lower than the fourth voltage V4 as shown in (a). That is, the voltage of the first electrode at the time when the falling ramp signal is supplied may be changed. Here, the seventh voltage V7 may be substantially the same voltage as the first voltage V1.

Alternatively, as shown in (b), the rising ramp signal may include a first rising ramp signal and a second rising ramp signal having different slopes.

The first rising ramp signal gradually rises from the first voltage V1 to the second voltage V2 at a first slope, and the second rising ramp signal is raised from the second voltage V2 to the third voltage V3. It can rise gradually with 2 slopes.

The second slope of the second rising ramp signal may be gentler than the first slope. As such, when the second slope is gentler than the first slope, the voltage rises relatively quickly until the setup discharge occurs, and the voltage rises relatively slowly during the setup discharge, thereby obtaining the effect of The amount of light generated by the setup discharge can be reduced.

Accordingly, the contrast characteristic can be improved.

Here, the eighth voltage V8, which is not mentioned in FIG. 9B, may be substantially the same voltage as the seventh voltage V7 of (a).

The pre reset period may be further included before the reset period described above. This will be described with reference to FIG. 10 attached thereto.

10 is a diagram for explaining a pre-reset period.

Referring to FIG. 10, a pre-reset period may be included before the reset period, and in this pre-reset period, the pre-ramp gradually decreases from the first electrode Y to the sixth voltage V6. The signal can be supplied.

In addition, while the pre ramp signal is supplied to the first electrode, a pre-sustain signal having a polarity opposite to the pre ramp signal may be supplied to the second electrode.

In addition, the pre-sustain signal can keep the pre-sustain voltage Vpz substantially constant. Here, the pre-sustain voltage Vpz may be approximately equal to the voltage of the sustain signal supplied in the subsequent sustain period, that is, the sustain voltage Vs.

As such, when the pre-ramp signal is supplied to the first electrode and the pre-sustain signal is supplied to the second electrode in the pre-reset period, wall charges of a predetermined polarity are accumulated on the first electrode, and the second electrode Overlying wall charges of opposite polarity accumulate on the first electrode. For example, positive wall charges may be accumulated on the first electrode, and negative wall charges may be accumulated on the second electrode.

Accordingly, it is possible to generate a setup discharge of sufficient intensity in the reset period after the pre-reset period, and thus, the initialization can be performed sufficiently stable.

In addition, even if the voltage of the rising ramp signal Ramp-Up supplied to the first electrode becomes smaller in the reset period, it is possible to generate the setup discharge of sufficient intensity.

From the viewpoint of securing the driving time, a pre-reset period is included before the reset period in the subfields arranged first in time among the subfields of the image frame, or before the reset period in two or three subfields of the subfields of the image frame. It is also possible to include a pre-reset period.

Alternatively, this pre-reset period may be omitted in all subfields.

On the other hand, in the address period after the reset period, a scan bias signal that substantially maintains the lowest voltage of the falling ramp signal, that is, a voltage higher than the fifth voltage V5, for example, the sixth voltage V6, is supplied to the first electrode.

In addition, a scan signal having a magnitude of Vy may be supplied to the first electrode from the scan bias signal.

On the other hand, the width of the scan signal in units of subfields may vary. That is, the width of the scan signal in at least one subfield may be different from the width of the scan signal in another subfield. For example, the width of the scan signal in the subfield located later in time may be smaller than the width of the scan signal in the preceding subfield. In addition, the reduction of the scan signal width according to the arrangement order of the subfields can be made gradually, such as 2.6 Hz (microseconds), 2.3 Hz, 2.1 Hz, 1.9 Hz, or 2.6 Hz, 2.3 Hz, 2.3 Hz, 2.1 Hz. .... 1.9 ㎲, 1.9 ㎲ and so on.

As such, when the scan signal is supplied to the first electrode, a data signal having a magnitude of Vd may be supplied to the third electrode to correspond to the scan signal.

As the scan signal and the data signal are supplied, an address discharge may be generated in the discharge cell to which the data signal is supplied while the voltage difference between the scan signal and the data signal and the wall voltage caused by the wall charges generated in the reset period are added. have.

Here, the sustain bias signal may be supplied to the second electrode to prevent the address discharge from becoming unstable due to the interference of the second electrode in the address period.

Here, the sustain bias signal may maintain a substantially constant sustain bias voltage Vz smaller than the voltage of the sustain signal supplied in the sustain period and larger than the voltage of the ground level GND.

Thereafter, in the sustain period for displaying an image, a sustain signal may be supplied to at least one of the first electrode and the second electrode. For example, a sustain signal may be alternately supplied to the first electrode and the second electrode.

When such a sustain signal is supplied, the discharge cell selected by the address discharge is sustained discharge between the first electrode and the second electrode when the sustain signal is supplied while the wall voltage in the discharge cell and the sustain voltage Vs of the sustain signal are added. , Display discharge may occur.

Next, FIG. 11 is a diagram for explaining another type of the sustain signal.

Referring to FIG. 11, a positive sustain signal and a negative sustain signal are alternately supplied to one of the first electrodes Y and the second electrode Z, for example, the first electrode. do.

As such, while a positive sustain signal and a negative sustain signal are supplied to any one electrode, a bias signal may be supplied to the other electrode, for example, the second electrode Z.

Here, the bias signal may maintain the voltage of the ground level GND substantially constant.

As shown in FIG. 11, when the sustain signal is supplied only to one of the first electrode Y and the second electrode Z, either one of the first electrode Y and the second electrode Z may be used. Only one driving board in which circuits for supplying a sustain signal to the electrode is arranged is required.

Accordingly, the overall size of the driving unit for driving the plasma display panel can be reduced, thereby reducing the manufacturing cost.

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 panel according to the exemplary embodiment of the present invention has a relative spacing between the first black layer or the second black layer and the partition wall disposed between the first electrode or the second electrode and the front substrate. As a result, the panel reflectance is reduced by the shading effect, thereby improving the contrast characteristic of the image displayed on the panel.

In addition, in the plasma display panel according to an embodiment of the present invention, one of the first black layer and the second black layer is disposed at a position adjacent to the partition wall, and the other is disposed at a position spaced apart from the partition wall. Even when the length is relatively small, the luminance is sufficiently high and the contrast characteristic is improved.

Claims (11)

A front substrate on which the first electrode and the second electrode parallel to each other are disposed; A first black layer disposed between the front substrate and the first electrode and having a color darker than a color of the first electrode; A second black layer disposed between the front substrate and the second electrode and having a color darker than the color of the second electrode; A rear substrate disposed to face the front substrate; And Barrier ribs defining a discharge cell between the front substrate and the rear substrate; Including, One of the first black layer and the second black layer is disposed at a position adjacent to the barrier rib, and the other is disposed at a position spaced apart from the barrier rib by a predetermined distance. The method of claim 1, The first electrode is an electrode to which a scan signal is supplied in an address period of a subfield. And the first black layer is disposed at a position spaced apart from the barrier rib by a predetermined distance, and the second black layer is disposed at a position adjacent to the barrier rib. The method of claim 1, The spacing between the first black layer and the second black layer is between 0.7 times and 2.5 times less than the spacing between any one of the first black layer or the second black layer disposed at a position adjacent to the partition wall and the partition wall. Display panel. The method of claim 1, The spacing between the first black layer and the second black layer is at least 0.7 times and not more than twice the spacing between any one of the first black layer or the second black layer disposed at a position adjacent to the partition wall. Display panel. The method of claim 1, The spacing between the first black layer and the second black layer is between 0.8 and 1.8 times less than the spacing between any one of the first black layer and the second black layer disposed at a position adjacent to the partition wall and the partition wall. Display panel. The method of claim 1, And a third black layer having a color darker than a color of at least one of the first electrode and the second electrode at a position corresponding to the barrier rib on the front substrate. The method of claim 6, And a spacing between the third black layer and any one of the first black layer and the second black layer is substantially the same as the spacing between the partition and either the first black layer or the second black layer. The method of claim 1, And a fourth black layer having a color darker than that of the partition wall. The method of claim 8, And a spacing between the fourth black layer and any one of the first black layer and the second black layer is substantially the same as the spacing between the partition and either the first black layer or the second black layer. The method of claim 1, The first electrode and the second electrode includes a transparent electrode and a bus electrode, And the first black layer and the second black layer are disposed between the transparent electrode and the bus electrode. The method of claim 1, And the spacing between the first black layer and the second black layer is substantially the same as the spacing between any one of the first black layer or the second black layer disposed at a position adjacent to the partition wall.

Images