KR100659063B1 - Plasma display panel - Google Patents

Abstract

An object of the present invention is to provide a plasma display panel having improved contrast in a clear room by a visible light absorbing layer disposed between a wall and a front substrate. To achieve the above object, the present invention provides a rear substrate and spaced apart from the rear substrate. A front substrate disposed between the front substrate and the rear substrate, a partition wall partitioning discharge cells, sustain electrode pairs extending across the discharge cells, and intersecting the sustain electrode pair in the discharge cell; Address electrodes extending across the discharge cells, a first dielectric layer covering the sustain electrode pairs, a second dielectric layer covering the address electrodes, a phosphor layer disposed in the discharge cells, the barrier ribs and the front surface A plasma display comprising a visible light absorbing layer disposed between the substrates and a discharge gas in the discharge cells. It provides you.

Description

Plasma display panel {Plasma display panel}

1 is a partially cutaway perspective view of a conventional plasma display panel according to the related art;

2 is a partially cutaway perspective view of the plasma display panel according to the first embodiment of the present invention;

3 is a vertical cross-sectional view showing the internal structure of the plasma display panel shown in FIG.

4 is a partially cutaway perspective view of a plasma display panel according to a second embodiment of the present invention;

FIG. 5 is a layout view of discharge cells, address electrodes, bus electrodes, and connectors illustrated in FIG. 4;

6 is a layout view corresponding to FIG. 5 as a first modified example of the plasma display panel according to the second embodiment;

FIG. 7 is a layout view corresponding to FIG. 5 as a second modified example of the plasma display panel according to the second embodiment.

Explanation of symbols on the main parts of the drawings

100, 200: plasma display panel

110: back substrate 112: sustain electrode pair

113: X electrode 114: Y electrode

116: first dielectric layer 119: protective layer

120: front substrate 122, 222, 322, 422: address electrode

124: visible light absorbing layer 125, 225, 325, 425: connection

126, 226: second dielectric layer 128: partition wall

129 phosphor layer 130 discharge cell

224, 324, 424 bus electrodes

The present invention relates to a plasma display panel, and more particularly, to a plasma display panel having improved clear room contrast by a visible light absorbing layer disposed between a partition and a front substrate.

Recently, a plasma display panel, which is drawing attention as a replacement of a conventional cathode ray tube display device, is discharged after a discharge gas is filled between two substrates on which a plurality of electrodes are formed. The phosphor formed in a predetermined pattern by the ultraviolet rays is excited to obtain a desired image.

FIG. 1 is an exploded perspective view partially showing a conventional alternating current three-electrode surface discharge plasma display panel 5. As used herein, "front" means the direction in which the image is displayed. Referring to FIG. 1, the plasma display panel 5 includes a rear substrate 10 and a front substrate 20 that face each other. A plurality of address electrodes 11 are arranged on the top surface of the back substrate 10, and the address electrodes 11 are embedded by the first dielectric layer 12. The partition wall 13 partitions the discharge cells 14 on the upper surface of the first dielectric layer 12. The phosphor layer 15 is applied to the inner surface of the discharge cell 14 partitioned by the partition 13 with a predetermined thickness. The front substrate 20 is a transparent substrate through which visible light can be transmitted. The front substrate 20 is mainly made of glass and is coupled to the rear substrate 10 provided with the partition wall 13. On the bottom of the front substrate 20, sustain electrode pairs 30 are formed to intersect the address electrodes 11. One sustaining electrode of the pair of sustaining electrodes 30 is the X electrode 21, and the other sustaining electrode is the Y electrode 22. Each of the sustain electrodes 21 and 22 includes transparent electrodes 21a and 22a and bus electrodes 21b and 22b. The sustain electrode pairs 30 are buried by the transparent second dielectric layer 23, and a protective layer 24 is formed on the bottom of the second dielectric layer 23. The protective layer 24 lowers the discharge voltage applied between the electrodes by emitting secondary electrons in the discharge cell to increase efficiency, and serves to protect the electrodes.

However, in the case of the plasma display panel 5, since the visible light absorption of the partition 13 is low, the amount of visible light incident from the outside is reflected by the partition 13 and is emitted to the outside again. The visible light emitted to the outside causes a glare phenomenon and reduces the bright room contrast of the plasma display panel 5.

In addition, since the sustain electrode pair 30 is disposed on the bottom surface of the front substrate 20 on which visible light is projected, there is a limit in the structure change to improve the luminous efficiency. In addition, since the protective layer 24 is formed on the bottom of the second dielectric layer 23, there is a problem in that transmittance of visible light generated in the discharge cells 14 is lowered.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a plasma display panel having improved clear room contrast by disposing a visible light absorbing layer between a partition and a front substrate.

Another object of the present invention is to provide a plasma display panel in which a transmittance of a front substrate is improved by disposing a pair of sustain electrodes on a rear substrate.

In order to achieve the above and other objects, the present invention provides a rear substrate, a front substrate spaced apart from the rear substrate, a partition wall disposed between the front substrate and the rear substrate, and partitioning the discharge cells; Sustain electrode pairs extending across the discharge cells, address electrodes extending across the discharge cells to intersect the sustain electrode pairs in the discharge cell, a first dielectric layer covering the sustain electrode pairs; A plasma display panel including a second dielectric layer covering the address electrodes, a phosphor layer disposed in the discharge cells, a visible light absorbing layer disposed between the barrier ribs and the front substrate, and a discharge gas in the discharge cell. To provide.

In the present invention, the visible light absorbing layer preferably has a higher visible light absorption than the partition wall. In addition, the visible light absorbing layer is preferably formed of a conductive material containing Ag, Cu or Al.

In the present invention, it is preferable that the address electrode is transparent and disposed at the center of the discharge cell.

The plasma display panel may further include a connection portion electrically connecting the address electrode and the visible light absorbing layer.

In the present invention, the sustain electrode pairs are disposed on the back substrate, and the address electrodes are disposed on the front substrate. In addition, the phosphor layer is preferably disposed between the sustain electrode pair and the front substrate.

(First embodiment)

FIG. 2 is an exploded perspective view showing a partial cutaway view of the plasma display panel 100 according to an exemplary embodiment of the present invention, and FIG. 3 is a vertical cross-sectional view showing the internal structure of the plasma display panel 100 shown in FIG. . In FIG. 3, the lower plate 160 is rotated 90 degrees to clearly show the internal structure of the plasma display panel 100.

2 and 3, the plasma display panel 100 according to an embodiment of the present invention includes an upper plate 150 and a lower plate 160. The upper plate 150 includes a front substrate 120, and the lower plate 160 includes a rear substrate 110 disposed to face the front substrate 120. The back substrate 110 and the front substrate 120 are spaced at predetermined intervals to define a plurality of discharge cells 130 partitioned by the partition wall 128 therebetween.

On the back substrate 110, the sustain electrode pairs 112 are arranged in parallel at predetermined intervals. One sustaining electrode of the pair of sustaining electrodes 112 functions as a common electrode as the X electrode 113, and the other sustaining electrode functions as a scanning electrode as the Y electrode 114. The X electrodes 113 and the Y electrodes 114 are formed in a stripe shape.

The sustain electrode pairs 112 are buried by the first dielectric layer 116 formed on the top surface of the back substrate 110. The first dielectric layer 116 is directly energized between the adjacent X electrode 113 and the Y electrode 114, and positive or negative electrons collide directly with the sustain electrodes 113 and 114 so that the X electrode 113 and the Y electrode 114 ) To induce charges and to accumulate wall charges.

Meanwhile, a protective layer 119 is formed on the upper surface of the first dielectric layer 116. The protective layer 119 prevents the first dielectric layer 116 and the sustain electrode pair 112 from being damaged by the sputtering of plasma particles and lowers the discharge voltage by emitting secondary electrons. The protective layer 119 may be formed by applying magnesium oxide (MgO) to the upper surface of the first dielectric layer 116 to a predetermined thickness. The MgO layer 119 is mainly formed as a thin film by sputtering or E-beam epaporation.

The front substrate 120 is a transparent substrate through which visible light can be transmitted, and is mainly made of glass, and a plurality of address electrodes are formed on the bottom surface of each discharge cell 130 in a stripe shape intersecting the sustain electrode pairs 112. 122) are formed. The address electrodes 122 are used to generate an address discharge for facilitating sustain discharge between the X electrode 113 and the Y electrode 114. More specifically, the address electrodes 122 lower the voltage for sustain discharge. The address discharge is a discharge that occurs between the Y electrode 114 and the address electrode 122.

The address electrodes 122 are buried by the second dielectric layer 126 formed on the bottom surface of the front substrate 120. The second dielectric layer 126 may be formed by applying a transparent dielectric material on a bottom surface of the front substrate 120 to a predetermined thickness. The second dielectric layer 126 is formed as a dielectric that can induce charge while preventing cations or electrons from colliding with the address electrode 122 during discharge and damaging the address electrode 122. Such dielectrics include PbO, B ₂ O ₃ , SiO ₂ and the like.

The partition wall 128 partitioning the plurality of discharge cells 130 is formed on the bottom surface of the second dielectric layer 126. However, the arrangement position of the partition wall 128 is not limited thereto, and the partition wall 128 may be formed on the passivation layer 119. In addition, although the partition wall 128 is illustrated as partitioning the discharge cells 130 in the form of a rectangular matrix in FIG. 2, the present invention is not limited thereto, and as long as a plurality of discharge spaces can be formed, partition walls of various patterns, for example, Open bulkheads, such as stripes, may of course be closed bulkheads, such as waffles, matrices, deltas, and the like. In addition, the closed partition wall may be formed such that the cross section of the discharge space is a polygon, such as a triangle, a pentagon, or a circle, an ellipse, or the like, in addition to the quadrangle.

The visible light absorbing layer 124 is disposed between the partition 128 and the front substrate 120. The visible light absorbing layer 124 is formed on the bottom surface of the front substrate 120, and is buried by the second dielectric layer 126 like the address electrode 122. The visible light absorbing layer 124 is spaced apart from the address electrode 122 at a predetermined interval and is formed to extend in one direction. The visible light absorbing layer 124 functions to absorb visible light incident from the outside, and preferably has a dark color. In particular, it is preferable that the visible light absorbing layer 124 has a higher visible light absorbance than the partition 128 for the improvement of bright room contrast.

As described above, when the dark visible light absorbing layer 124 is disposed in front of the discharge cells 130, the transmittance of the plasma display panel is decreased because the visible light absorbing layer 124 interferes with the transmission of the visible light generated in the discharge cells 130. Therefore, the visible light absorbing layer 124 is preferably disposed in the projection area of the partition 128 to the front substrate 120. The visible light absorbing layer 124 may be formed of various materials. The visible light absorbing layer 124 may be formed by mixing a dark pigment with a transparent dielectric material, and may be formed using a material including Ru, Co, Cr, and the like.

In the discharge cells 130, Ne, Xe, or a mixed discharge gas thereof is injected. In addition, red, green, and blue light emitting phosphor layers 129 are applied to the bottom surface of the second dielectric layer 126 between the side surfaces of the partition wall 128 and the partition wall 128, respectively. This is to form a transmissive structure as a whole by placing the phosphor layer 129 in front of the sustain electrode pairs 112 generated during sustain discharge. However, the arrangement position of the phosphor layer 129 is not limited thereto. On the other hand, the phosphor layer 129 has a component that generates ultraviolet light by receiving ultraviolet light, the red light emitting phosphor layer formed in the red discharge cell includes a phosphor such as Y (V, P) O ₄ : Eu, and green discharge The green light emitting phosphor layer formed in the cell includes a phosphor such as Zn ₂ SiO ₄ : Mn, and the blue light emitting phosphor layer formed in the blue discharge cell includes a phosphor such as BaMgAl ₁₀ O ₁₇ : Eu.

In the plasma display panel 100 according to the present invention having the structure as described above, visible light emitted from the phosphor layer 129 passes through the front substrate 120 and is emitted to the outside. Therefore, the plurality of address electrodes 122 disposed on the bottom surface of the front substrate 120 are made of indium tin oxide (ITO), which is a transparent conductive material to allow visible light to pass therethrough, whereas the plurality of address electrodes 122 are disposed on the top surface of the back substrate 110. Since the sustain electrode pairs 112 do not require transparency, they may be made of a general conductive metal material. As described above, since the sustain electrode pairs 112 can be formed of a metal material having excellent conductivity such as Ag, Al, or Cu and low resistance, the response speed due to the discharge is high, the signal is not distorted, and it is necessary for the sustain discharge. It is possible to reduce the power consumption has a number of advantages.

Referring to the operation of the plasma panel 100 according to the preferred embodiment of the present invention configured as described above are as follows.

An address discharge is generated by applying an address voltage between the address electrode 122 and the Y electrode 114. As a result of the address discharge, wall charges are accumulated on the electrodes, so that the discharge cells 130 for sustain discharge are selected. Then, when a discharge holding voltage is applied between the X electrode 113 and the Y electrode 114 of the selected discharge cell 130, the wall charges accumulated on the X electrode 113 and the Y electrode 114 are moved. The sustain discharge is generated, and the ultraviolet rays are emitted while the energy level of the discharged gas excited during the sustain discharge is lowered. The ultraviolet rays excite the phosphor 129 coated in the discharge cell 130. As the energy level of the excited phosphor 129 decreases, visible light is emitted, and the visible light is emitted from the second dielectric layer 126 and the front substrate. It is emitted through the 120 to form an image that can be recognized by the user.

Second Embodiment

FIG. 4 is a partially cutaway perspective view of the plasma display panel 200 according to the second embodiment of the present invention, and FIG. 5 shows the discharge cells 130, the address electrodes 222, and the bus electrode shown in FIG. 4. 224 and layouts of connections 225. Here, the description will be focused on the differences from the above-described embodiments. Like reference numerals refer to like elements.

Referring to FIG. 4, the plasma display panel 200 includes a top plate 250 and a bottom plate 160. Since the structure of the lower plate 150 is the same as the first embodiment, it will be omitted here.

A plurality of address electrodes 222 extending across the discharge cells 130 are disposed on the bottom of the transparent front substrate 120. The address electrodes 222 extend with a predetermined width. In addition, bus electrodes 224 are disposed in parallel with the address electrodes 222. Here, one bus electrode 224 corresponds to one address electrode 222, and a plurality of connection parts 225 electrically connect between the bus electrode 224 and the address electrode 222. The address electrodes 222 are formed to extend across the center of the discharge cells 130 on the bottom surface of the front substrate 220, and are formed using ITO, which is generally a transparent material. However, since ITO has poor electrical conductivity, there is a risk that the electric signal transmitted through the address electrode 222 is distorted. Therefore, the bus electrode 224 for applying an electrical signal to the transparent address electrode 222 is disposed separately. The bus electrode 224 is formed using a material having excellent conductivity. In general, the bus electrode 224 has a two-layer or three-layer structure. In the case of the three-layer structure, the first electrode, the conductive layer, and the second Cr layer are stacked from the front, respectively. The first and second Cr layers are formed of a material containing Cr, and serve to protect the conductive layer. In particular, when the Cr ₂ O ₃ layer is formed by oxidizing the first Cr layer disposed at the foremost front, the Cr ₂ O ₃ layer is dark, so that the bus electrode 222 moves to the front substrate 120 of the partition 128. It is preferable to arrange in the projection area of. In this case, since the absorption rate of visible light incident from the outside by the dark Cr ₂ O ₃ layer increases, the clear room contrast of the plasma display panel is improved. In addition, the foremost portion of the bus electrode 224, such as the first Cr layer, may be formed using another material having a dark color, and is preferably formed using Ru or Co. The conductive layer of the bus electrode 224 is preferably formed using Ag, Cu, Al, or the like having excellent electrical conductivity. As described above, when the visible light absorption of the foremost portion of the bus electrode 224 is high, the bus electrode 224 itself performs the function of the visible light absorbing layer.

As described above, the connection portions 225 electrically connecting the bus electrode 224 and the address electrode 222 may be formed in various forms, and may be formed discontinuously at predetermined intervals, and each discharge cell ( At least one connection part may be formed at 130. These connecting portions 225 may be formed using a transparent material or a dark material. Preferably, in order to reduce the resistance from the bus electrode 224 to the address electrode 222, it may be integrally formed using the same material as the bus electrode 224 having excellent conductivity.

The bus electrode 224, the connection part 225, and the address electrode 222 are buried by the second dielectric layer 226. The second dielectric layer 226 may be formed by applying a transparent dielectric material to a bottom of the front substrate 120 to a predetermined thickness.

Operation of the plasma display panel 200 according to the second embodiment having the above structure is similar to that of the first embodiment, and thus a detailed description thereof will be omitted.

6 shows a first modification of the plasma display panel according to the second embodiment. FIG. 6 is a layout view of address electrodes 322, connection parts 325, and bus electrodes 324 disposed in front of the partition wall 128. Here, the description will be focused on the differences from the first and second embodiments. Like reference numerals refer to like elements.

Referring to FIG. 6, address electrodes 322 are disposed across the discharge cells 130, and bus electrodes 324 are spaced apart from the address electrodes 322 at predetermined intervals. The bus electrodes 324 are disposed in front of the partition wall 128, and the bus electrodes 324 and the address electrodes 322 are electrically connected to each other by the connecting portions 325 disposed at each of the discharge cells 130. do. Although the address electrodes 322 are formed using a transparent material, this also lowers the transmittance of visible light generated in the discharge cell 130, and therefore, it is preferable to narrow the width of the address electrode 322 in terms of improving the transmittance. Do. However, in consideration of the address discharge between the Y electrode 114 and the address electrode 322, when the address electrode 322 is formed in a narrow width, the discharge voltage increases. Therefore, an address electrode having a shape that not only lowers the discharge voltage but also improves the transmittance is required. In this variation, it is formed wider than the width (W ₁₎ of the portion at which the address electrode width (W2) of the portion to be connected to the connecting portion 325 adjacent to each other. That is, the address electrode 322 extends to have the first width W ₁ , and then the width of the address electrode 322 is increased to the second width W ₂ at the portion connected to the connecting portion 325, and then again the first width W 1. It extends while repeating narrowing to (W ₁ ). Therefore, not only the visible light transmittance is improved by the portion having the first width W ₁ , but the discharge area is increased by the portion having the second width W ₂ , thereby reducing the address discharge voltage. In addition, since the portion having the second width W _{2 is} connected to the dark connecting portion 325, the length of the connecting portion 325 disposed in front of the discharge cell 130 is reduced to further improve the visible light transmittance.

FIG. 7 is a diagram illustrating a second modified example of the second embodiment, in which the address electrodes 422, the connection parts 425, and the bus electrodes 424 are disposed in front of the partition wall 128. The second modification is different from the first modification in that one connection part 425 is disposed in each discharge cell 130. The number of connection parts 425 disposed in each discharge cell 130 is selected in consideration of the visible light transmittance and the address discharge voltage. Similarly to the first modification, the width W ₄ of the address electrode connected to the connecting portion 425 is formed to be wider than the width W ₃ of the adjacent portion. Thus, not only the visible light transmittance is improved, but also the address discharge voltage is reduced.

The plasma display panel according to the present invention has the following effects.

First, since the visible light absorbing layer is disposed between the front substrate and the partition wall, excellent transmittance is maintained and clear room contrast is improved.

Second, since the sustain electrode pair and the protective layer are disposed on the rear substrate, the transmittance of the front substrate is improved and the luminance is increased.

Although the present invention has been described with reference to the embodiments shown in the drawings, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

Claims (12)

Back substrate; A front substrate spaced apart from the rear substrate; A partition wall disposed between the front substrate and the rear substrate and partitioning discharge cells; Sustain electrode pairs disposed on the rear substrate and extending across the discharge cells; Address electrodes extending across the discharge cells to intersect the sustain electrode pair in the discharge cell; A first dielectric layer covering the sustain electrode pairs; A second dielectric layer covering the address electrodes; A phosphor layer disposed in the discharge cells; A visible light absorbing layer disposed between the partition wall and the front substrate; And And a discharge gas in the discharge cell. The method of claim 1, And the visible light absorbing layer is disposed in a projection area of the partition wall toward the front substrate. The method of claim 1, And the visible light absorbing layer has a higher visible light absorbance than the partition wall. The method of claim 1, And the visible light absorbing layer is formed of a conductive material. The method of claim 4, wherein And the visible light absorbing layer is formed of Ag, Cu, or Al. The method of claim 1, And the address electrode is transparent. The method of claim 1, And the address electrode is disposed at the center of the discharge cell. The method of claim 1, And the address electrode and the visible light absorbing layer extend in parallel to each other. The method of claim 1, And a connection part electrically connecting the address electrode and the visible light absorbing layer. The method of claim 9, And a width of a portion of the address electrode connected to the connection portion is wider than a width of an adjacent portion. The method of claim 1, And the address electrodes are disposed on the front substrate. The method of claim 1, And the phosphor layer is disposed between the sustain electrode pair and the front substrate.

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