KR100542191B1 - Plasma display panel - Google Patents

Abstract

The present invention relates to a plasma display panel which prevents coloring of a transparent electrode due to migration of lead ions to enhance the color quality of the screen, and suppresses reflection of external light to improve the contrast of the screen.

First and second substrates opposed to each other at arbitrary intervals; Address electrodes positioned on the first substrate; A partition wall disposed in a space between the first substrate and the second substrate to partition the discharge cells; A red, green, or blue fluorescent layer located in each discharge cell, and formed on the second substrate along a direction orthogonal to the address electrode, and composed of a pair of scan electrodes and common electrodes composed of a transparent electrode and a bus electrode; A sustain electrode, and an upper dielectric layer covering the sustain electrodes on the second substrate, provided at one end of the transparent electrode corresponding to the center of the discharge cell, and ionized between the second substrate and the upper dielectric layer. Provided is a plasma display panel including a transfer prevention layer that prevents coloring of the transparent electrode by transfer of metal ions.

Plasma, display, address electrode, sustain electrode, common electrode, scan electrode, dielectric layer, partition wall, transfer

Description

Plasma Display Panel {PLASMA DISPLAY PANEL}

1 is a partially exploded perspective view of a plasma display panel according to an embodiment of the present invention.

FIG. 2 is a partial plan view illustrating the assembled state of FIG. 1. FIG.

3 is a partial cross-sectional view of the second substrate shown in FIG. 1.

4 is a partial cross-sectional view of a first substrate showing a first modification of the embodiment of the present invention.

5 and 6 are partial plan views of the plasma display panel showing the second and third modified examples of the embodiment of the present invention, respectively.

7 is a cross-sectional view taken along the line A-A of FIG.

8 is a partially exploded perspective view of a plasma display panel according to the prior art.

9 is a partial cross-sectional view of the front substrate shown in FIG. 8.

The present invention relates to a plasma display panel, and more particularly, to a plasma display panel having a three-electrode surface discharge structure including an address electrode on a rear substrate, a scan electrode and a common electrode on a front substrate to form discharge cells. It is about.

In general, a plasma display panel (hereinafter referred to as a 'PDP') is a display device for realizing an image by exciting phosphors by vacuum ultraviolet rays caused by gas discharge occurring in a discharge cell. It is attracting attention as a thin display.

8 is a partially exploded perspective view showing an AC PDP having a three-electrode surface discharge structure according to the prior art, and FIG. 9 is a partial cross-sectional view of the front substrate shown in FIG.

Referring to the drawings, an address electrode 3, a partition 5, and a fluorescent layer 7 are formed on a rear substrate 1, and a scan electrode 11 and a common electrode 13 are formed on a front substrate 9. The sustain electrode 15 is formed. The scan electrode 11 and the common electrode 13 are transparent electrodes 11a and 13a having a high light transmittance, such as indium tin oxide (ITO), respectively, and metal bus electrodes positioned at the edges of the transparent electrodes 11a and 13a. (11b, 13b).

The sustain electrode 15 and the address electrode 3 are respectively covered with the upper dielectric layer 17 and the lower dielectric layer 19, and the discharge gas inside the discharge cell where the address electrode 3 and the sustain electrode 15 cross each other is discharge gas ( Predominantly Ne-Xe mixed gas). For reference, in the drawing, reference numeral 21 denotes an MgO protective film covering the upper dielectric layer 17, and reference numeral 23 denotes a black stripe.

With the above-described configuration, an address voltage Va is applied between the address electrode 3 and the scan electrode 11 to select a discharge cell in which light emission will occur through address discharge, and the scan electrode 11 of the selected discharge cell. When the sustain voltage Vs is applied between the common electrode 13 and the common electrode 13, plasma discharge occurs in the discharge cell. In addition, vacuum ultraviolet rays are emitted from the excitation atoms of Xe produced during plasma discharge, and the vacuum ultraviolet rays excite the fluorescent layer 7 of the discharge cells to emit visible light, thereby enabling color display.

In the PDP operating as described above, the front substrate 9 is made of a conventional soda lime glass containing sodium carbonate (Na ₂ CO ₃ ), and is manufactured by a float method in which a molten glass is flowed on tin to be heated and polished. do. In addition, the upper dielectric layer 17 covering the front substrate 9 and the sustain electrode 15 is made of lead glass based on 60 to 65% by weight of lead oxide (PbO).

However, the alkali material Na on the front substrate 9 ionizes the lead oxide contained in the upper dielectric layer 17 so that the ionized lead is polarized to the low potential electrode during the PDP driving process. As a result, a phenomenon in which lead precipitates as crystals occurs at the tip portions 11c and 13c of the transparent electrodes 11a and 13a located at the center of the discharge cell. This phenomenon is estimated to occur when lead ions (Pb ²⁺ ) generated by the reaction of sodium ions (Na ⁺ ) of the soda lime glass with lead in the upper dielectric layer 17 move toward the transparent electrodes 11a and 13a. .

As the lead ions generated by the reaction between the front substrate 9 and the upper dielectric layer 17 are migrated to the front ends 11c and 13c of the transparent electrode, the conventional PDP has a front end 11c, 13c) is colored yellow, which results in coloring the PDP screen as a whole yellow, resulting in deterioration of the color quality of the screen. Furthermore, in the related art, since external light reflection occurs at the tip portions 11c and 13c of the colored transparent electrode, there is a disadvantage in that the contrast of the screen is lowered.

Therefore, the present invention is to solve the above problems, an object of the present invention is to prevent the coloring of the transparent electrode due to the transfer of lead ions to improve the color quality of the screen, by suppressing the reflection of external light occurring at the tip of the transparent electrode An object of the present invention is to provide a plasma display panel capable of improving contrast of a screen.

In order to achieve the above object, the present invention,

First and second substrates disposed at random intervals, address electrodes positioned on the first substrate, partition walls disposed in a space between the first substrate and the second substrate to partition discharge cells, Sustain electrodes formed of a pair of red, green, or blue fluorescent layers located in the discharge cells, and a scan electrode and a common electrode formed along a direction orthogonal to the address electrodes on the second substrate, and formed of a transparent electrode and a bus electrode. And an upper dielectric layer covering the sustain electrodes on the second substrate and provided at one end of the transparent electrode corresponding to the center of the discharge cell and ionized between the second substrate and the upper dielectric layer. It provides a plasma display panel comprising a transfer preventing layer for preventing the coloring of the transparent electrode by the transfer of.

The transfer prevention layer is disposed outside the front end of the transparent electrode while in contact with the front end side of the transparent electrode, and is formed in a stripe pattern along the front end of the transparent electrode. The transfer preventing layer is composed of a black conductor or a non-conductor having a dark color substantially close to black.

The transfer prevention layer may be formed of a laminated structure of a black metal layer and a white metal layer, wherein the black metal layer includes at least one metal selected from the group consisting of Ru, Co, and Cr, and the white metal layer is made of Ag, Au, Al, and Cu. At least one metal selected from the group.

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

1 is a partially exploded perspective view of a plasma display panel according to an exemplary embodiment of the present invention, FIG. 2 is a partial plan view illustrating an assembled state of FIG. 1, and FIG. 3 is a partial cross-sectional view of the second substrate illustrated in FIG. 1.

Referring to the drawings, in the plasma display panel according to the present embodiment (hereinafter referred to as 'PDP'), the first substrate 2 and the second substrate 4 are disposed to face each other at arbitrary intervals, and between the two substrates. Discharge cells 6R, 6G and 6B are provided in the space to implement an arbitrary color image with visible light emission by an independent discharge mechanism of each discharge cell 6R, 6G and 6B.

In detail, the address electrodes 8 are formed in one direction (Y direction of the drawing) on the inner surface of the first substrate 2, and cover the address electrodes 8 to cover the first substrate 2. The lower dielectric layer 10 is formed over the entire inner surface. The address electrodes 8 are formed in a stripe pattern, for example, and are arranged side by side with a predetermined distance from the neighboring address electrodes 8.

On the lower dielectric layer 10, a partition 12, for example, a stripe 12 having a stripe pattern parallel to the address electrode 8 is formed, and a red color is formed on the side surface of the partition 12 and the upper surface of the lower dielectric layer 10. Green and blue fluorescent layers 14R, 14G and 14B are provided in this order. At this time, the shape of the partition wall 12 is not limited to the stripe pattern, it may be formed of a closed structure such as a lattice or other patterns.

In addition, the inner surface of the second substrate 4 facing the first substrate 2 is formed of the scan electrode 16 and the common electrode 18 along the direction orthogonal to the address electrode 8 (the X direction in the drawing). An electrode 20 is formed, and a transparent upper dielectric layer 22 and an MgO passivation layer 24 are positioned over the entire inner surface of the second substrate 4 while covering the sustain electrodes 20.

In this embodiment, the scan electrode 16 and the common electrode 18 are positioned at one edges of the stripe patterned transparent electrodes 16a and 18a and the transparent electrodes 16a and 18a, respectively. It consists of metal bus electrodes 16b and 18b which complement conductivity. Indium tin oxide (ITO) is preferable as the transparent electrodes 16a and 18a, and any one of silver (Ag), gold (Au), aluminum (Al), and copper (Cu) is used as the bus electrodes 16b and 18b. A white metal electrode containing is preferable.

By the combination of the first substrate 2 and the second substrate 4 described above, the discharge space where the address electrode 8 and the sustain electrode 20 intersect constitute one discharge cell, and the discharge cells 6R and 6G. , 6B) is filled with discharge gas (mainly Ne-Xe mixed gas). Meanwhile, a black stripe 26 may be positioned in the non-discharge region between the sustain electrodes 20 to absorb external light to increase the contrast of the screen.

Here, the PDP according to the present embodiment includes a transfer prevention layer 28 at one end of the transparent electrodes 16a and 18a positioned at the center of the discharge cells 6R, 6G, and 6B to transfer lead ions. It provides a configuration for preventing the coloring of the transparent electrodes (16a, 18a) accordingly.

In this embodiment, the transfer prevention layer 28 is disposed outside the front end portions of the transparent electrodes 16a and 18a while contacting the front end sides of the transparent electrodes 16a and 18a, as shown in FIGS. 2 and 3. It has a width and is formed in a stripe pattern along the leading ends of the transparent electrodes 16a and 18a. The transfer preventing layer 28 is preferably made of a conductor or non-conductor exhibiting black or dark color close to black.

Thus, when the second substrate 4 is made of ordinary soda lime glass containing sodium carbonate, and the upper dielectric layer 22 is lead glass based containing 60 to 65 wt% of lead oxide (PbO), the second substrate 4 Sodium ions (Na ⁺ ) on the surface react with lead (Pb) contained in the upper dielectric layer 22 to generate lead ions (Pb ²⁺ ), and lead ions are directed toward the front ends of the transparent electrodes 16a and 18a. When a moving transfer phenomenon occurs, the transfer prevention layer 28 blocks the transfer of lead ions toward the front ends of the transparent electrodes 16a and 18a to prevent coloring of the transparent electrodes 16a and 18a.

Furthermore, since the transfer prevention layer 28 exhibits a black color or a dark color close to black, the transfer prevention layer 28 absorbs light incident on the PDP from the outside to improve the contrast of the screen. The transport barrier layer 28 preferably contains any one of Fe, Mn, Cr, Ru, TiO ₂ and Co ₃ O ₄ , mainly black, and close to black when it contains Co ₃ O ₄ . Indicates.

Table 1 below shows the result of comparing the contrast of the screen in the PDP according to the present embodiment (see Fig. 8) without the transfer preventing layer and the PDP according to the present embodiment provided with the transfer preventing layer 28. In particular, in the PDP according to the present embodiment, the change in contrast of the screen according to the change in the width (w, see FIG. 2) of the transfer prevention layer 28 is measured and shown. In the following table, a is defined by the following equation, and the vertical pitch Pv of the discharge cells 6R, 6G, and 6B in the following experiment is 1080 μm in both the comparative examples and the examples.

Comparative example Example 1 Example 2 Example 3 Example 4 Example 5 a 0 1.85 3.70 5.56 7.41 9.26 Contrast 400 440 460 470 500 520 Example 6 Example 7 Example 8 Example 9 Example 10 a 12.96 16.67 20.37 24.05 27.73 Contrast 550 580 620 660 700

As shown in the table, the contrast of the screen is generally improved in the PDP according to the present embodiment with the transfer prevention layer 28 as compared with the conventional PDP without the transfer prevention layer, and the width w of the transfer prevention layer 28 is increased. It can be seen that the greater the), the better the contrast enhancement effect.

In particular, in the present embodiment, the width w of the transfer prevention layer 28 with respect to the vertical pitch Pv of the discharge cells 6R, 6G, 6B is preferably 1.85 to 27.73%. When the a value is less than 1.85%, it is difficult to effectively prevent the transfer of lead ions, and it is difficult to obtain a substantial contrast enhancement effect. When the a value exceeds 27.73%, the aperture ratio of the PDP is lowered to decrease the brightness of the screen. This is because when the transfer preventing layer 28 is made of a conductor, a short between the scan electrode 16 and the common electrode 18 can be caused.

As described above, the PDP according to the present embodiment improves the color quality of the screen by preventing the coloring of the transparent electrodes 16a and 18a by the transfer preventing layer 28 described above, and absorbs light incident on the PDP from the outside to It has the advantage of increasing the contrast.

Next, modifications of the embodiment of the present invention will be described with reference to FIGS. 4 to 6.

FIG. 4 is a first modification, in which case the transfer prevention layer 28 'is formed of a laminated structure of a black metal layer 28a and a white metal layer 28b, based on the structure of the above-described embodiment, to form a PDP. The black metal layer 28a of the transfer preventing layer 28 'is a metal material containing Ru, Co or Cr, and the white metal layer 28b is made of a metal material containing Ag, Au, Al or Cu.

In particular, in this modification, the bus electrodes 16b 'and 18b' of the scan electrode 16 'and the common electrode 18' also comprise black metal layers 16c and 18c and white metal layers 16d and 18d. Preferably, the black metal layers 16c and 18c of the bus electrodes 16b 'and 18b' are made of the same material as the black metal layer 28a of the transfer preventing layer 28, and the white metal layers of the bus electrodes 16b 'and 18b'. 16d and 18d are made of the same material as the white metal layer 28b of the transfer preventing layer 28.

As a result, in the present modification, the bus electrodes 16b 'and 18b' and the transfer preventing layer 28 can be formed in one process, which has the advantage of simplifying the manufacturing process of the PDP.

FIG. 5 is a second modification, in which case the PDP is formed by further forming an extension 30 connecting the transfer prevention layer 28 and the black stripe 26 based on the structure of the above-described embodiment. The extension part 30 is made of a conductor or non-conductor having the same black color or darker color as black as the transfer preventing layer 28 to improve the contrast of the screen. Preferably, the extension part 30 is formed along the direction of the partition wall 12 at a position corresponding to the partition wall 12 and is formed to have a smaller width than the partition wall 12.

6 and 7 show a third modification, in which case the first extension part 32 connecting the transfer preventing layer 28 and the black stripe 26 and the bus electrode 16b are based on the structure of the above-described embodiment. , 18b) is further formed with a second extension 34 positioned along the bus electrode direction (X direction in the figure) to form a PDP. The first extension portion 32 has the same configuration as the extension portion 30 of the second variant described above, and the second extension portion 34 is preferably formed with the same width as the bus electrodes 16b and 18b.

In the second modification and the third modification described above, when the black stripe 26 is a conductor, the extension portion 30, the first extension portion 32, and the second extension portion 34 are formed of a non-conductor to form a black. The conduction between the stripe 26 and the scan electrode 16 and the common electrode 18 is prevented.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications and changes can be made within the scope of the claims and the detailed description of the invention and the accompanying drawings. Naturally, it belongs to the range of.

As described above, according to the present invention, when lead ions generated by the reaction of the second substrate and the upper dielectric layer are transferred to the transparent electrode, the aforementioned transfer preventing layer blocks the transfer of lead ions to prevent coloring of the transparent electrode. Improve color quality. Furthermore, as the transfer prevention layer appears black, light incident on the PDP from the outside is absorbed to improve the contrast of the screen.

Claims (17)

First and second substrates opposed to each other at arbitrary intervals; Address electrodes positioned on an opposite surface of the first substrate to a second substrate; A partition wall disposed in a space between the first substrate and the second substrate to partition discharge cells; A red, green, or blue fluorescent layer located within each discharge cell; Sustain electrodes formed on a surface opposite to the first substrate of the second substrates in a direction orthogonal to the address electrode, and configured as a pair of scan electrodes and common electrodes formed of a transparent electrode and a bus electrode; And An upper dielectric layer covering the sustain electrodes on the second substrate; A plasma display provided on one end of the transparent electrode corresponding to the center of the discharge cell and including a transfer preventing layer for preventing coloring of the transparent electrode by transfer of ionized metal ions between the second substrate and the upper dielectric layer; panel. The method of claim 1, And the transfer preventing layer is disposed outside the front end of the transparent electrode while in contact with the front end side of the transparent electrode. The method of claim 1, And the transfer preventing layer is formed in a stripe pattern along a leading end of the transparent electrode. The method of claim 1, And the transfer preventing layer is black or a dark color close to black. The method according to claim 1 or 4, And the transfer preventing layer comprises at least one material selected from the group consisting of Fe, Mn, Ru, TiO ₂ and Co ₃ O ₄ . The method of claim 1, And the transfer preventing layer satisfies the following conditions. 1.85 ≤ a ≤ 27.73 Here, a represents [width (micrometer) of a transfer prevention layer / vertical pitch (micrometer) of a discharge cell] x100. The method of claim 1, And the transfer preventing layer has a laminated structure of a black metal layer and a white metal layer. The method of claim 7, wherein And the black metal layer comprises at least one metal selected from the group consisting of Ru, Co, and Cr. The method of claim 7, wherein And the white metal layer comprises at least one metal selected from the group consisting of Ag, Au, Al, and Cu. The method according to claim 1 or 7, And the bus electrode has a stacked structure of a black metal layer and a white metal layer. The method of claim 1, And the plasma display panel further comprises a black stripe positioned in a non-discharge area between the sustain electrodes. The method of claim 11, And the plasma display panel further comprising an extension part connecting the transfer preventing layer and the black stripe. The method of claim 12, And the extension part is formed along the partition wall direction at a position corresponding to the partition wall. The method of claim 13, And the extension portion has a dark color close to black or black. The method of claim 12, The plasma display panel further comprises a first extension connecting the transfer prevention layer and the black stripe, and a second extension positioned on the bus electrode along a bus electrode direction. The method of claim 15, And the first extension part is formed along the partition wall direction at a position corresponding to the partition wall. The method of claim 15, And the first and second extension portions have a dark color of black or near black.

Images