KR20050113533A - Plasma display panel - Google Patents

Abstract

SUMMARY OF THE INVENTION An object of the present invention is to provide a plasma display panel having a structure in which the aperture ratio of an upper substrate is remarkably improved, permanent afterimages do not occur, and edge curls do not occur in an upper partition wall in which electrodes are embedded. To this end, the present invention is a transparent upper substrate, a lower substrate disposed in parallel with the upper substrate, disposed between the upper substrate and the lower substrate to define the light emitting cell together with the upper substrate and the lower substrate, and each of the discharge cells in the horizontal portion, vertical And an upper portion formed of a dielectric, upper discharge walls formed in a dielectric, upper discharge electrodes disposed in the upper partitions to surround the discharge cells, and disposed in the upper partitions to surround the discharge cells. Lower discharge electrodes spaced from the upper discharge electrode, the phosphor layer disposed in the discharge cell, and the discharge gas in the discharge cell; It provides a plasma display panel provided.

Description

Plasma display panel {Plasma display panel}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display panel that uses a gas discharge to express characters or images, and more particularly, to a plasma display panel having an enlarged surface on which a discharge occurs.

Recently, a device employing a plasma display panel as a flat panel display device has a large screen, and has excellent characteristics of high definition, ultra-thin, light weight, and wide viewing angle. It is attracting attention as a large flat panel display device.

The plasma display panel is classified into a direct current (DC) type, an alternating current (AC) type, and a hybrid type according to an applied discharge voltage, and classified into a counter discharge type and a surface discharge type according to a discharge structure.

In the DC plasma display panel, all electrodes are exposed to a discharge space. Thus, the transfer of charge is made directly between the corresponding electrodes. In contrast, in the AC plasma display panel, at least one electrode is surrounded by a dielectric layer, and discharge is performed by an electric field of wall charge, instead of direct charge transfer between the corresponding electrodes.

In the DC plasma display panel, since there is a problem in that the electrode is severely damaged due to the direct movement of charges between the corresponding electrodes, in recent years, an AC type plasma display having a three-electrode surface discharge structure has been developed. Panels have been generally employed.

The conventional surface discharge plasma display panel 10 including the AC three-electrode surface discharge plasma display panel includes an upper substrate 20 and a lower substrate 30 as shown in FIG. 1.

The lower substrate 30 includes an address electrode 33 for generating an address discharge, a lower dielectric layer 35 embedding the address electrode, a partition wall 37 partitioning discharge cells, and both sides of the partition wall and the partition wall. The phosphor layer 39 applied to the lower substrate not formed is formed.

The upper substrate 20 disposed to be spaced apart from and opposed to the lower substrate 20 includes X and Y electrodes 22 and 23 for generating a sustain discharge, and an upper dielectric layer 25 having the X and Y electrodes 22 and 23 embedded therein. ) And a protective film 29. The X electrode 22 is usually provided with a transparent X electrode 22a and a bus X electrode 22b disposed on one side of the transparent X electrode, and the Y electrode 23 is usually provided with a transparent Y electrode 23a. And a bus Y electrode 23b disposed on one side of the transparent Y electrode.

Visible light emitted from the phosphor layer 39 in the discharge space is emitted to the outside through the upper substrate 20.

However, in the conventional plasma display panel as described above, the X electrode 22, the Y electrode 23, and the upper dielectric layer 25 sequentially formed on the X and Y electrodes are disposed below the upper substrate 20. The protective film 29 exists. These factors have a serious problem that the visible light transmittance of about 60%.

Further, in the conventional surface discharge plasma display panel 10, an electrode which causes discharge is formed on the upper surface of the discharge space, that is, the inner surface of the upper substrate 20 through which visible light passes, so that discharge is generated on the inner surface and diffused. Therefore, there is an inherent problem of low luminous efficiency.

Furthermore, in the conventional surface discharge plasma display panel 10, when used for a long time, the charged particles of the discharge gas cause ion sputtering on the phosphor by an electric field, causing a permanent afterimage.

SUMMARY OF THE INVENTION The present invention is to solve the above problems, to provide a plasma display panel that can significantly expand the opening area and transmittance as compared to the conventional plasma display panel, and can significantly expand the discharge area by greatly expanding the discharge surface. .

Another object of the present invention is to provide a plasma display panel capable of low voltage driving, significantly improving luminous efficiency, and drastically reducing permanent afterimage phenomenon.

Another object of the present invention is to concentrate the plasma by the discharge to a predetermined portion of the discharge space, for example, the center portion to efficiently utilize the space charge of the plasma, and has a structure that does not occur edge curl phenomenon in the dielectric coating the electrode It is to provide a plasma display panel.

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

Transparent upper substrate;

A lower substrate disposed in parallel with the upper substrate;

A corner disposed between the upper substrate and the lower substrate to define a light emitting cell together with the upper substrate and the lower substrate, and connecting the horizontal portion, the vertical portion, and the horizontal portion and the vertical portion to each discharge cell, and having rounded inner edges. An upper partition wall having a portion and formed of a dielectric;

 Upper discharge electrodes disposed in an upper partition wall to surround the discharge cell;

Lower discharge electrodes disposed in an upper partition wall to surround the discharge cell and spaced apart from the upper discharge electrode;

A phosphor layer disposed in the discharge cell; And

It provides a plasma display panel having a discharge gas in the discharge cell.

In this case, it is preferable that the inner surface of the corner portion is rounded with a radius of curvature of 7% to 50% of the distance between the horizontally neighboring upper partition centers.

The upper discharge electrodes may extend in one direction, and the lower discharge electrodes may extend to cross the upper discharge electrodes.

Alternatively, the plasma display panel may further include an address electrode. In this case, the upper discharge electrode and the lower discharge electrode may have a ladder shape extending in one direction, and may extend to intersect the upper discharge electrode and the lower discharge electrode. Address electrodes may be further provided. In this case, the address electrodes are preferably formed on the lower substrate and covered by a dielectric layer, and a phosphor layer is formed on the dielectric layer.

Alternatively, the address electrode may be disposed in the upper partition wall. In this case, it is preferable that a phosphor layer is formed on the lower substrate.

The upper discharge electrode may have a ladder shape extending in one direction, and the lower discharge electrode may have a ladder shape extending to cross the upper discharge electrode, and a phosphor layer may be formed on the lower substrate.

In addition, at least the side surface of the upper partition wall is preferably covered with a protective film.

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

2 and 3 illustrate a plasma display panel according to a preferred embodiment of the present invention. Referring to the drawings, the plasma display panel 100 according to the present invention includes an upper substrate 120, a lower substrate 130, an upper partition 170, an upper discharge electrode 122, a lower discharge electrode 123, and a phosphor. Layer 139 and a discharge gas (not shown).

The transparent upper substrate 120 is disposed in parallel with the lower substrate 130 so that visible light passes and the image is projected. An upper partition wall 170 is formed between the upper substrate and the lower substrate. The upper partition wall 170 is disposed in the non-discharge portion to define the discharge cell (C). In the upper partition wall 170, the upper discharge electrode 122 and the lower discharge electrode 123 are formed to surround the discharge cell C by being spaced apart from each other.

The phosphor layer 139 is disposed in a space defined by the upper partition wall 170, the upper substrate 120, and the lower substrate 130.

The discharge gas 140 is present in the discharge cell (C).

The upper substrate 120 is made of a material having good light transmittance such as glass, through which visible light is emitted to the outside.

The lower substrate 130 supports the address electrodes 133 and is usually made of a material mainly containing glass.

The upper discharge electrode 122 and the lower discharge electrode 123 are made of a conductor such as copper, aluminum, and silver. In the present embodiment, the lower discharge electrode 123 and the upper discharge electrode 122 are preferably disposed to surround the upper side of the discharge cell C. Here, the upper side of the discharge cell is a phosphor layer on the lower partition 137. It means a portion that is higher than the formed portion.

In FIG. 2, the lower discharge electrode 123 and the upper discharge electrode 122 are each formed as one electrode. However, in the present invention, the lower discharge electrode 123 and the upper discharge electrode 122 each have two or more secondary electrodes. It may be provided.

The upper discharge electrode 122 and the lower discharge electrode 123 may be disposed to cross each other. The upper discharge electrode 122 may extend along the light emitting cells C in one row, and the lower discharge electrode 123 may extend along the light emitting cells in another row crossing the rows of the light emitting cells. In this case, one of the upper discharge electrode 122 and the lower discharge electrode 123 may serve as an address electrode causing an address discharge and a sustain electrode causing a sustain discharge.

In contrast, the upper discharge electrode 122 and the lower discharge electrode 123 extend in one direction in parallel with each other, and the address electrodes 133 may extend so as to intersect the upper discharge electrode 122 and the lower discharge electrode 123. Can be.

In this case, the address electrode 133 may be disposed in the upper partition wall 170. In this case, it is preferable that the phosphor layer 139 is formed on the lower substrate.

In addition, the address electrode 133 may be formed on the upper surface of the lower substrate 130. In this case, the address electrodes 133 are disposed between the lower substrate 130 and the phosphor layer 139. It is preferable that a dielectric layer 135 is formed between the 133 and the phosphor layer 139.

In the case where the address electrode is further provided in the plasma display panel according to an exemplary embodiment of the present invention, as shown in FIG. 4, the upper discharge electrode 122 and the lower discharge electrode 123 may each have a ladder shape and may be parallel to each other. It is preferably formed to extend in one direction, the address electrodes 133 are preferably extended to cross the upper discharge electrode 122 and the lower discharge electrode 123.

Here, the lower discharge electrode 123 extends to intersect with the address electrode 133, that is, the column of discharge cells through which the address electrode 133 passes and the discharge cell through which the lower discharge electrode 123 passes. It means that the columns intersect. In addition, the upper discharge electrode 122 extends in parallel with the lower discharge electrode 123, which means that the upper discharge electrode 122 is disposed together with the lower discharge electrode 123 at regular intervals.

In this case, the address electrodes 133 are used to generate an address discharge for facilitating sustain discharge between the lower discharge electrode 123 and the upper discharge electrode 122. More specifically, the address electrodes 133 may be configured to generate a voltage at which the sustain discharge starts. It acts to lower.

The address discharge is a discharge occurring between the electrode serving as the Y electrode and the address electrode 133 among the upper discharge electrode 122 and the lower discharge electrode 123. When the address discharge is completed, the upper discharge electrode 122 and the lower discharge electrode are discharged. In the discharge electrode 123, cations are accumulated on the electrode side serving as the Y electrode, and electrons are accumulated on the electrode serving as the X electrode, thereby facilitating sustain discharge.

When the address electrodes 133 are formed on the lower substrate 130, the address electrode 133 is covered by the dielectric layer 135, and the phosphor layer 139 is preferably formed on the dielectric layer 135.

The dielectric layer 135 is formed as a dielectric that can induce charge while preventing cations or electrons from colliding with the address electrode 133 during discharge, and inducing charge. Such dielectrics include PbO, B ₂ O ₃ , and the like. SiO ₂ and the like.

In FIG. 2, the upper partition wall 170 divides the discharge cells C into a matrix, but is not limited thereto. The upper partition wall 170 may be partitioned into another shape such as a honeycomb.

The upper partition wall 170 defining the discharge cell is formed of a dielectric. The upper partition wall 170 prevents the upper discharge electrode 122 and the lower discharge electrode 123 from being directly energized during sustain discharge, and prevents charged particles from directly colliding with the electrodes 122 and 123 to damage them. And induces charged particles to accumulate wall charges.

The side surface of the upper partition wall 170 is preferably covered by a protective film 129. The passivation layer 129 is not an essential component, but it is preferably formed because charged particles collide with the upper partition wall 170 to prevent damage to the upper partition wall and emit a lot of secondary electrons during discharge. .

A lower partition 137 may be formed below the upper partition 170 to define a discharge cell C together with the upper partition. The lower partition wall 137 defines a discharge cell and between red, green, and blue discharge cells corresponding to one subpixel of a red light emitting subpixel, a green light emitting subpixel, and a blue light emitting subpixel constituting a unit pixel. Prevents false discharges. In this case, the lower partition wall 137 may be formed separately from the upper partition wall 170 as shown in FIG. 2, but may be formed integrally with the same material as the upper partition wall 170. In addition, the upper partition 170 and the lower partition 137 may be formed in the same closed pattern.

The phosphor layer 139 includes a component that emits visible light by receiving ultraviolet rays emitted by the sustain discharge. The red phosphor layer formed on the red light emitting subpixel includes phosphors such as Y (V, P) O ₄ : Eu. And the green phosphor layer formed on the green light emitting subpixel includes phosphors such as Zn ₂ SiO ₄ : Mn, YBO ₃ : Tb, and the like, and the blue phosphor layer formed on the blue light emitting subpixel includes phosphors such as BAM: Eu and the like. .

As the discharge gas charged in the discharge cell, a penning mixture such as Xe-Ne, Xe-He, Xe-Ne-He, etc. is used.

The reason why Xe is used as the main discharge gas is that because Xe is a chemically stable inert gas, it is not dissociated due to discharge, but because the atomic number is large, the excitation voltage is lowered and the wavelength of light emitted is increased. to be. The reason for using He or Ne as a buffer gas is because the voltage reduction effect due to the panning effect due to Xe and the sputtering effect due to the high pressure are reduced.

The upper substrate 120 adopted in the present invention includes a transparent Y electrode 23a, a transparent X electrode 22a, a bus X electrode 22b, and a bus as in the conventional plasma display panel 10 shown in FIG. The Y electrode 23b, the upper dielectric layer 27, and the protective film 29 do not exist. This significantly improves the forward transmittance of visible light from about 60% to about 90% of the related art. Therefore, if the image is implemented at the luminance of the conventional level, the upper and lower discharge electrodes 122 and 123 can be driven at a relatively low voltage, resulting in improved luminous efficiency.

In this case, since the upper discharge electrode 122 and the lower discharge electrode 123 are not disposed on the upper substrate 120 through which visible light is transmitted, but are disposed on the side of the discharge space, a transparent electrode having a large resistance is used as the discharge electrode. Since it is possible to use a low-resistance electrode, such as a metal electrode, as a discharge electrode without the need for use, the discharge response speed is high, and low voltage driving is possible without distortion of the waveform.

As shown in FIG. 5, the upper partition wall 170 adopted in the present invention has a horizontal portion 173, a vertical portion 177, and an edge portion connecting the horizontal portion and the vertical portion for each discharge cell C. FIG. 175. 2 and 5, the horizontal portion 173 indicates an upper partition wall 170 formed in a direction crossing the address electrode 133, and the vertical portion 177 is connected to the address electrode 133. Pointing to the upper partition wall 170 formed in a parallel direction.

In this case, the corner portion 175 is rounded at a constant curvature of the inner surface 175 '. This is to prevent edge curls from occurring in the upper partition wall 170 during the manufacturing process of the upper partition wall, thereby preventing the edge part from bursting and reducing the concentration of the electric field at the corner part. .

That is, in the present invention, the upper partition wall 170 is formed of a dielectric layer, and upper and lower discharge electrodes 122 and 123 are buried therein. The upper partition wall having such a structure is formed by stacking a plurality of layers.

For example, as shown in FIG. 3, the one-layer bulkhead portion 170a, the two-layer bulkhead portion 170b, and the three-layer bulkhead portion 170c are stacked downward in order from the upper substrate 120, so that the upper bulkhead 170 may be formed.

This is to form the upper and lower discharge electrodes 122 and 123 in the upper partition wall 170. When the manufacturing process is briefly described, the first partition wall part 170a is formed, and then the upper discharge is formed. An electrode 122 is formed on the lower surface 170a_g of the one-layer partition wall. Thereafter, the two-layer partition wall portion 170b is formed to fill the upper discharge electrode 122. Next, a lower discharge electrode 123 is formed on the lower surface 170b_g of the two-layer partition wall part, and then a three-layer partition wall part 170c is formed to fill the upper and lower discharge electrodes 122 and 123. Is manufactured.

In order to form the one-layer bulkhead portion 170a, the two-layer bulkhead portion 170b, and the three-layer bulkhead portion 170c of the upper bulkhead 170, the dielectric paste is patterned into a predetermined shape, and the patterning is performed. In the step, the firing process must be performed to lose the resin component in the paste, and edge curl is generated in this process.

That is, the binder, which combines the solvent and the dielectric paste during the firing process, is discharged to the outside by high heat, and the portion except the edge is contracted and the edge is curled up due to the tensile force (surface tension) during heating. Edge curl Ec occurs.

In particular, the corner portion 175 is a point where the horizontal portion 173 and the vertical portion 177 meet, as shown in FIG. 6, the one-layer partition wall portion 170a, the two-layer partition wall portion 170b, and the three-layer partition wall portion. An acute edge is generated on the lower surfaces 170a_g, 170b_g, and 170c_g of 170c, so that the edge curl Ec phenomenon is remarkably displayed at the corners.

When the edge curl (Ec) is generated in the corner portion 175, the arc (arc) is generated in the portion where the edge curl (Ec) is generated during discharge. In addition, as the dielectric layer is formed at an acute angle, the dielectric is destroyed at the point where the edge curl Ec occurs and the dielectric thickness is not constant. As a result, the wall charge behavior at the corner portion 175 is different from the wall charge behavior at the horizontal portions 173 and the vertical portion 177, thereby causing an abnormal discharge.

When such an abnormal discharge occurs, the electric field is not concentrated to the center of the light emitting cell, and as a result, the discharge volume is reduced, resulting in a decrease in light efficiency.

Therefore, in order to prevent the edge curl from occurring in the corner portion 175, the inner surface 175 of the corner portion is preferably rounded to have a constant radius of curvature α.

In this case, as shown in FIG. The inner side surface 175 ′ of the corner portion is preferably rounded to a radius of curvature α of 7% to 50% of the distance P between the horizontally neighboring upper bulkhead centers, which is the radius of curvature α. When the inner surface is formed with a radius of curvature of less than 7%, the rounding degree of the corner portion is too small to prevent the occurrence of edge curl, and the electric field is not concentrated at the center of the light emitting cell. This is because the portion where the round meets becomes another corner when the percentage is exceeded.

According to the plasma display panel having the structure as described above, first, since there is no other element other than the substrate in the portion of the upper substrate through which visible light passes, the aperture ratio can be significantly improved, and the transmittance at 60% or less of the conventional Up to about 90%.

Second, since edge curl does not occur during the manufacture of the upper partition, electric field concentration is possible at the center of the discharge cell, and abnormal discharge does not occur, thereby increasing luminous efficiency.

Third, the light emitting area for generating the discharge becomes large, and the discharge path is shortened, so that low voltage driving is possible.

Fourth, a stable discharge is possible by securing a wide voltage margin, sufficient panel withstand voltage can be secured so that proper charge can be accumulated, and as a result, low discharge failure does not occur and the discharge stability of the panel is secured.

Fifth, the discharge response speed is fast and low voltage driving is possible. In the plasma display panel and the flat panel display device having the same according to the present invention, since the discharge electrode is not disposed on the upper substrate through which visible light is transmitted, it is disposed on the side of the discharge space. Therefore, it is necessary to use a transparent electrode having a high resistance as the discharge electrode. Since a low-resistance electrode such as a metal electrode can be used as the discharge electrode, the discharge response speed is high, and low-voltage driving is possible without distortion of the waveform.

In addition, as the structure of the plasma display panel is drastically changed as compared with the related art, the discharge area is greatly enlarged, the amount of plasma is greatly increased, and thus, a lot of ultraviolet rays can be emitted. The luminous efficiency can be improved.

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.

1 is an exploded perspective view showing a conventional plasma display panel;

2 is an exploded perspective view illustrating a plasma display panel according to an embodiment of the present invention;

3 is a cross-sectional view taken along line III-III of FIG. 2,

4 is a layout view of electrodes provided in the plasma display panel of FIG. 2;

5 is a cross-sectional view taken along the line VV of FIG. 3,

FIG. 6 is a cross-sectional view taken along line VI-VI of FIG. 5.

Explanation of symbols on main parts of drawing

100: plasma display panel 120: upper substrate

122: upper discharge electrode 123: lower discharge electrode

129: protective film 130: lower substrate

133: address electrode 135: dielectric layer

137: lower partition 139: phosphor layer

170: upper partition 170a: one-layer partition

170b: two-layer bulkhead 170c: three-layer bulkhead

173: upper partition horizontal portion 175: upper partition corner

177: upper partition longitudinal portion C; Light emitting cell

Ec: edge curl α: corner radius of curvature

P: Distance between horizontally neighboring upper bulkhead centers

Claims (8)

Transparent upper substrate; A lower substrate disposed in parallel with the upper substrate; A corner disposed between the upper substrate and the lower substrate to define a light emitting cell together with the upper substrate and the lower substrate, and connecting the horizontal portion, the vertical portion, and the horizontal portion and the vertical portion to each discharge cell, and having rounded inner edges. An upper partition wall having a portion and formed of a dielectric;  Upper discharge electrodes disposed in an upper partition wall to surround the discharge cell; Lower discharge electrodes disposed in an upper partition wall to surround the discharge cell and spaced apart from the upper discharge electrode; A phosphor layer disposed in the discharge cell; And And a discharge gas in the discharge cell. The method of claim 1, And the inner surface of the corner portion is rounded with a radius of curvature of 7% to 50% of the distance between the horizontally neighboring upper partition centers. The method of claim 1, And the upper discharge electrodes extend in one direction, and the lower discharge electrodes extend to intersect the upper discharge electrode. The method of claim 1, The upper discharge electrode and the lower discharge electrode has a ladder shape extending in one direction, And an address electrode extending to intersect the upper discharge electrode and the lower discharge electrode. The method of claim 4, wherein And the address electrode is formed on a lower substrate and covered by a dielectric layer, and a phosphor layer is formed on the dielectric layer. The method of claim 4, wherein And the address electrode is disposed in an upper partition, and a phosphor layer is formed on the lower substrate. The method of claim 1, And the upper discharge electrode has a ladder shape extending in one direction, the lower discharge electrode has a ladder shape extending to intersect the upper discharge electrode, and a phosphor layer is formed on the lower substrate. The method of claim 1, And at least a side surface of the upper partition wall is covered by a protective film.