KR20050122516A - Plasma display panel - Google Patents

Abstract

A plasma display panel is disclosed. The present invention includes a front substrate; a rear substrate disposed to face the substrate; a dielectric wall defining a discharge space together with the front and rear substrates; and a discharge space disposed between the dielectric wall and the rear substrate. A discharge electrode having a first and a second discharge electrode embedded in the dielectric wall and disposed up and down along the circumference of the discharge space; and red, green, and blue phosphor layers applied in the partition wall; And a portion of the dielectric wall contacting the partition wall to minimize contact area by forming a curvature to reduce the contact area, thereby preventing a shape in which the partition wall is damaged by applying a force to a local area of the upper end of the partition wall.

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, and more particularly, to a plasma display panel in which a predetermined curvature is formed in a dielectric wall in which a discharge electrode is embedded, thereby facilitating a manufacturing process.

In general, a plasma display panel injects a discharge gas between two substrates on which a plurality of discharge electrodes are formed, and discharges the discharge, and excites the fluorescent material of the phosphor layer by the ultraviolet rays generated thereby to implement desired numbers, letters, or graphics. A flat display device is referred to.

The plasma display panel can be classified into a direct current type and an alternating current type according to a type of driving voltage applied to a discharge cell, for example, a discharge type, and can be classified into a counter discharge type and a surface discharge type according to the configuration of the electrodes.

The DC plasma display panel has a structure in which all electrodes are exposed to a discharge space, and charges are directly transferred between corresponding electrodes. On the other hand, in the AC plasma display panel, at least one electrode is embedded in the dielectric layer, and instead of direct charge transfer between the corresponding electrodes, ions and electrons generated by the discharge adhere to the surface of the dielectric layer so that the wall voltage is reduced. (wall voltage) is formed, and the discharge can be maintained by the sustaining voltage.

On the other hand, in the opposite discharge type plasma display panel, a plurality of discharge electrodes are provided to face each unit pixel, and addressing discharge and sustain discharge are generated between the two electrodes. On the other hand, in the surface discharge plasma display panel, an address electrode and corresponding X and Y electrodes are provided for each unit pixel to generate addressing discharge and sustain discharge.

In the conventional three-electrode surface discharge plasma display panel which is widely used, a dielectric layer for embedding the X and Y electrodes formed on the front substrate and a partition wall disposed between the front and rear substrates to define a discharge space are in contact with each other. As a result, a phenomenon in which part of the partition wall is broken during assembly occurs. These debris enters the red, green, and blue phosphor layers applied in the partition walls, causing defects of pixels.

Korean Patent Laid-Open Publication No. 03-22701 disclosed in FIGS. 1A to 1C discloses a plasma display panel which prevents such a phenomenon.

Referring to the drawings, in the conventional plasma display panel, the partition wall 110 is formed to have protrusions extending outward of the discharge cell on at least one side of the discharge cell 120, and further, the length of the protrusions and the material forming the partition wall By adjusting the composition ratio, the projections are formed to be higher than the surroundings of the discharge cells by shrinkage in the firing step, and the pixel defects are generated even when damage occurs in the partition wall 110 by contacting the partition wall 111 and the front substrate outside the pixel. Is preventing.

On the other hand, the plasma display panel of the conventional three-electrode surface discharge structure is the visible light generated from the phosphor layer is transmitted through the front substrate to express the brightness, X and Y electrodes along the inner surface of the front substrate, and a dielectric layer to embed it; Since the protective film layer is formed, the light transmittance of the visible light is less than 60%, and there is a problem as a high efficiency flat panel display.

In addition, the X and Y electrodes are formed on the inner surface of the front substrate through which visible light passes, so that the discharge is diffused, and the discharge diffuses from the gap of the X and Y electrodes to the surroundings, but mainly along the plane Therefore, the utilization of the whole discharge space is low.

Recently, in order to solve the problem of the conventional plasma display panel having a three-electrode surface discharge structure, research is being conducted to improve the discharge efficiency by changing the structure in which the discharge electrodes are arranged.

In the case of the newly developed plasma display panel, a means for preventing a part of the partition wall from being damaged by entering the phosphor layer due to contact between the dielectric layer embedding the X and Y electrodes and the partition wall is required.

SUMMARY OF THE INVENTION 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 in which a discharge electrode is provided along a side surface of a discharge space, thereby improving discharge efficiency.

Another object of the present invention is to provide a plasma display panel having a curvature at a contact portion between a dielectric wall filling a sustain electrode and a partition wall on which a phosphor layer is applied, thereby preventing pixel defects due to breakage of the partition wall.

In order to achieve the above object, the plasma display panel according to an aspect of the present invention,

A front substrate;

A rear substrate disposed to face the front substrate;

A dielectric wall disposed between the front and rear substrates and defining a discharge space together with the front and rear substrates;

A partition wall disposed between the dielectric wall and the rear substrate and defining a discharge space together with the dielectric wall;

A discharge electrode embedded in the dielectric wall and having first and second discharge electrodes disposed up and down along the circumference of the discharge space;

It includes; red, green, blue phosphor layer applied in the partition wall,

A portion of the dielectric wall in contact with the partition wall is characterized in that the curvature is formed to reduce the contact area.

In addition, the dielectric wall is formed to face from the front substrate to the back substrate, the end of the dielectric wall is characterized in that it is in contact with the end of the partition wall with a predetermined curvature.

In addition, the end portion of the dielectric wall is characterized in that the portion in contact with the end portion of the partition wall is the apex of the curved portion.

Further, the portion where the dielectric wall and the partition wall contact each other is characterized by the following equation (1).

<Equation 1>

Here, C is the width of the portion where the dielectric wall and the partition contact, and A and B are the widths of the non-contact portion formed on both sides of the portion where the dielectric wall and the partition contact.

Furthermore, the first discharge electrode extends in one direction of the discharge space, and the second discharge electrode extends in a direction crossing the first discharge electrode.

In addition, the first and second discharge electrodes are X and Y electrodes extending along one direction of the discharge space, and further comprising an address electrode extending in a direction crossing the first and second discharge electrodes. .

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

3 illustrates a state in which a plurality of discharge electrodes is disposed according to an embodiment of the present invention.

Referring to the drawings, a substrate 210 made of a transparent material and glass is provided. A partition wall 220 is formed on the surface of the substrate 210 to define a discharge space. The partition wall 220 includes a first partition wall 221 disposed in the X direction and a second partition wall 222 formed integrally with the first partition wall 221 and disposed in the Y direction. The first and second partitions 221 and 222 are coupled to each other to form a grid. Alternatively, the partition wall 220 is not limited to any structure that defines a discharge space such as a meander type or a delta type.

The first discharge electrode 230 is disposed on the partition wall 220. The first discharge electrodes 230 are disposed in a substantially rectangular shape along the circumference of each discharge cell, and have a ladder structure connected between adjacent electrodes along the X direction. Accordingly, the same voltage is applied between the electrodes arranged in the X direction. On the other hand, the first discharge electrodes 230 are separated by a predetermined interval along the Y direction. Therefore, different voltages are applied between the electrodes arranged in the Y direction.

In addition, the second discharge electrode 240 is disposed in the discharge space in a direction crossing the first discharge electrode 230. The second discharge electrode 240 may have any shape as long as it is disposed in a direction crossing the first discharge electrode 230. The second discharge electrode 240 is disposed separately in the X direction.

The first and second discharge electrodes 230 and 240 may be configured as two electrodes or three electrodes depending on whether the panel is a counter discharge type or a discharge type. In addition, each of the first and second discharge electrodes 230 and 240 may be configured in plural or at least one electrode may be arranged in plural. In addition, the first and second discharge electrodes 230 and 240 may not be limited to any one structure such that the first and second discharge electrodes 230 and 240 may be disposed together around the discharge space corresponding to the partition wall 220.

Hereinafter, in the embodiment described below, the first discharge electrode is composed of sustain electrodes having X and Y electrodes arranged up and down, and the second discharge electrode is a three-electrode surface discharge plasma display panel composed of address electrodes. Let's explain.

3 is a diagram illustrating a partial cut-away view of the plasma display panel 300 according to an exemplary embodiment of the present invention.

Referring to the drawings, the plasma display panel 300 includes a front substrate 310 and a rear substrate 320 disposed in parallel with the front substrate 310. The front and back substrates 310 and 320 are joined by frit glass along edges of the opposite inner surfaces to form a closed space.

The front substrate 310 is made of a transparent substrate, for example, soda lime glass.

The back substrate 320 is made of substantially the same material as the front substrate 310. An address electrode 330 is disposed on an inner surface of the rear substrate 320. The address electrode 330 is composed of a plurality of strips and is disposed in a direction parallel to the Y direction of the substrate 320. The address electrode 330 is formed across each unit discharge cell, and is made of a metal material having excellent conductivity, such as silver paste.

The address electrode 330 is buried by the dielectric layer 340. The dielectric layer 340 is formed of a transparent dielectric, for example, a highly dielectric material such as PbO-B ₂ O ₃ -SiO _2, and is formed on the top surface of the rear substrate 320 to fill the address electrode 330. It is applied to the whole. Alternatively, the dielectric layer 340 may be selectively buried only in the portion where the address electrode 330 is formed.

A dielectric wall 350 is disposed between the front and rear substrates 310 and 320 to define a discharge space therebetween. The dielectric wall 350 is formed by adding various fillers to glass paste. The dielectric wall 350 may include a first dielectric wall 351 disposed in a direction (X direction) orthogonal to the address electrode 330, and a first dielectric wall 351 arranged in a direction (Y direction) parallel to the address electrode 330. Two dielectric walls 352 are included. The first dielectric wall 351 extends integrally in a direction opposite from the inner side walls of the pair of adjacent second dielectric walls 352 to define a grid-shaped discharge space.

Alternatively, the dielectric wall 350 may be embodied in various forms, such as meander, delta, hexagon, or stripe. In addition, the discharge space defined by the dielectric wall 350 may be replaced with a polygonal shape, a circular shape, or another shape as long as the discharge space may be defined in addition to the quadrangle.

The storage electrode 360 is disposed in the dielectric wall 350. The sustain electrode 360 includes an X electrode 361 disposed relatively to the front substrate 310, and a Y electrode 362 disposed relatively to the rear substrate 320. The Y electrode 362 is separately disposed under the X electrode 361. Since the X and Y electrodes 361 and 362 are electrically insulated, different voltages may be applied. These X and Y electrodes 361 and 362 are disposed along the circumference of the discharge space. The X and Y electrodes 361 and 363 form a closed loop for each discharge space.

The inner surface of the dielectric wall 350 is formed of a material such as magnesium oxide (MgO) such that ions generated in the panel 300 along the four sides of the discharge space emit secondary electrons by interaction with the surface. The protective film layer 370 is formed. The protective layer 370 is applied to each discharge space.

A partition wall 380 is further formed between the dielectric wall 350 and the rear substrate 320. The partition wall 380 is made of a low dielectric material, unlike the dielectric wall 350. The partition wall 380 is formed in a substantially same shape at a portion corresponding to the dielectric wall 350.

The partition 380 may include a first partition 381 disposed in a direction (X direction) orthogonal to the address electrode 330, and a second partition wall disposed in a direction (Y direction) parallel to the address electrode 330. 382 is provided. The first and second partitions 381 and 382 are integrally coupled to each other to form a lattice shape.

When only the dielectric wall 350 is formed between the front and back substrates 310 and 320, a single wall defines a discharge space, and the dielectric wall 350 and the partition wall 380 are both front and back substrates. If formed between (310) and (320), it becomes a structure that defines a discharge space that is a double wall of a material having a different dielectric constant.

Meanwhile, in the discharge space partitioned by the front and rear substrates 31 and 320, the dielectric wall 350, and the partition wall 380, neon (Ne) -xenon (Xe) or helium (He) -xenon A mixed gas such as (Xe) is injected.

In addition, red, green, and blue phosphor layers 390 that are excited by ultraviolet rays generated from the discharge gas and emit visible light are formed. In this case, the phosphor layer 390 may be coated on any surface of the discharge space, but is preferably applied to the inner surface of the partition 380 and the upper surface of the dielectric layer 340 to a predetermined thickness.

At this time, the end portion of the dielectric wall 350 in contact with the partition wall 380 has a predetermined curvature by physically and chemically etching, so that the narrow portion, preferably a line contact when sealing the partition wall 380. .

4 is a view illustrating the discharge electrode of FIG. 3 separately.

Referring to the drawing, the address electrode 330 is strip-shaped and extends across each discharge space S indicated by a dotted line.

The X electrode 361 is disposed in a direction crossing the address electrode 330. The X electrode 361 is arranged in a rectangular structure for each discharge cell along the circumference of the discharge space. The X electrodes 361 are connected to each other between adjacent electrodes arranged in the X direction, and the same voltage is applied thereto. In addition, the X electrodes 361 are separated from each other between the electrodes arranged in the Y direction, and different voltages are applied. Accordingly, the X electrode 361 has a ladder structure connected to each other between adjacent electrodes in the X direction, and has a structure spaced apart by a predetermined interval along the Y direction.

The Y electrode 362 is separated from the lower portion of the X electrode 361 and has a strip structure arranged in parallel with the X electrode 361. Like the X electrode 361, the Y electrode 362 has a ladder shape connected to each other between adjacent electrodes arranged in the X direction and is spaced apart from each other by a predetermined interval along the Y direction.

The X and Y electrodes 361 and 362 are embedded in the dielectric wall 350 (refer to FIG. 3) while being spaced vertically apart from each other. The X and Y electrodes 361 and 362 are preferably made of a metal material having excellent conductivity, such as silver paste or chromium-copper-chromium (Cr-Cu-Cr).

Meanwhile, the X and Y electrodes 361 and 362 may include a plurality of electrodes for each electrode or may form a plurality of at least one discharge electrode depending on whether the panel is a counter discharge type or a surface discharge type. Etc. It is not limited to this embodiment.

In addition, the X and Y electrodes 361 and 362 disposed along the circumference of adjacent discharge cells in the direction (X direction) crossing the address electrode 330 have not only a ladder structure but also electrodes along the circumference of each discharge cell. These are disposed, and adjacent electrodes may be connected to each other by conductive connecting members.

FIG. 5 illustrates a discharge cell in a state in which the panel 300 of FIG. 3 is coupled.

Referring to the drawings, a dielectric wall 350 formed of a double wall for defining a discharge space and a partition wall 380 disposed below are disposed between the front and rear substrates 310 and 320.

In the dielectric wall 350, the X electrode 361 and the Y electrode 362 are disposed to be separated up and down. The passivation layer 370 is coated on the surface of the dielectric wall 350. Red, green, and blue phosphor layers 390 are formed on the inner surface of the partition wall 380 for each discharge cell. The red, green, and blue phosphor layers 390 are formed of respective phosphors, and the red phosphor layer is composed of (Y, Gd) BO ₃ ; Eu ⁺³ , and the green phosphor layer is Zn ₂ SiO _4. It is preferable that it is made of: Mn ²⁺ and the blue phosphor layer is made of BaMgAl ₁₀ O ₁₇ : Eu ²⁺ .

Here, the upper end 353 of the dielectric wall 350 is in contact with the inner surface of the front substrate 310, and the lower end 354 is in contact with the upper end 383 of the partition 380.

The lower end 354 of the dielectric wall 350 has a predetermined curvature and forms a vertex of the curved portion at a portion in contact with the upper end 383 of the partition 380. Accordingly, the area of contact between the lower end portion 354 of the dielectric wall 350 and the upper end portion 383 of the partition wall 380 is reduced. Preferably, the portion where the dielectric wall 350 and the partition wall 380 contact each other is formed in line contact.

In this case, the width of the contact portion between the lower end portion 354 of the dielectric wall 350 and the upper end portion 383 of the partition wall 380 is referred to as C, and the widths of the non-contact portions on both sides are A and B, respectively. The following equation must be satisfied.

[Equation 1]

When the number of defects of the pixel at the time of forming the curvature of the dielectric wall 350 according to the applicant's experiment is measured as follows.

A + B 0 50 100 150 C 60 (A + B) / C 0 0.83 1.66 2.55 Defects 18 10 0 0

Here, A and B are the widths of the non-contact portions between the lower end portion 354 of the dielectric wall 350 and the upper end portion 383 of the partition wall 380, and C is the lower end portion 354 and the partition wall of the dielectric wall 350 ( 380 is the width of the contacted portion between the upper ends 383. In addition, the number of defects refers to the number of pixels generated when the dielectric wall 350 and the partition wall 380 are coupled to each other when a force is applied only to a local portion of the partition wall 380.

Referring to Table 1, as the width of the non-contacted portions of the lower end 354 of the dielectric wall 350 and the upper end 383 of the partition wall 380 increases in the order of 0, 50, 100, 150, the defects of pixels are increased. It can be seen that the number is significantly reduced to 18, 10, 0, 0.

The operation of the plasma display panel 300 having the above structure will be described with reference to FIG. 5.

First, when a predetermined address voltage is applied between the address electrode 330 and the Y electrode 362 from an external power source, the discharge cells to be emitted are selected. Wall charges are accumulated on the Y electrode 362 of the selected discharge cell.

Subsequently, when a voltage of “+” is applied to the X electrode 361 and a voltage higher than this is applied to the Y electrode 362, the wall is caused by the voltage difference applied between the X and Y electrodes 361 and 362. The charge will move.

The movement of the wall charges creates a plasma by colliding with the discharge gas atoms in the discharge space, and this discharge is likely to occur from the gap between the X electrode 361 and the Y electrode 362 where a relatively strong electric field is formed. Becomes high.

As a result, since the X electrode 361 and the Y electrode 362 are formed along the four sides of the discharge space, the possibility of discharge is greatly increased.

Subsequently, if the voltage difference between the X electrode 361 and the Y electrode 362 is still sufficiently large as time passes, the electric field formed between the two electrodes 361 and 362 is gradually concentrated so that the discharge is discharged. It spreads throughout the space.

Since the discharge in this embodiment is generated at four sides of the discharge space and diffuses to the center of the discharge space, the diffusion range is greatly increased. In addition, since the plasma generated by the discharge is formed in a ring type along the side of the discharge space and diffuses to the center portion, the volume is greatly increased so that the amount of visible light is greatly increased, and the plasma is concentrated in the center portion of the discharge space. The electric charge can be utilized to enable low voltage driving, and the light emitting efficiency can be improved.

If the voltage difference between the X and Y electrodes 361 and 362 is lower than the discharge voltage after the discharge is formed in this manner, the discharge no longer occurs, and the space charge and the wall charge are formed in the discharge space. At this time, if the polarities of the voltages applied to the X and Y electrodes 361 and 362 are reversed, the discharge is generated again with the help of the wall charge. If the polarities of the X and Y electrodes 361 and 362 are changed immediately, the first discharge process is repeated. The discharge is stably generated while repeating this process.

At this time, the ultraviolet rays generated by the discharge excite the fluorescent material of the phosphor layer 390 applied to each discharge space. Through this process, visible light is obtained. The generated visible light is emitted into the discharge space to realize a still image or a moving picture.

As described above, the plasma display panel of the present invention can obtain the following effects.

First, by minimizing a contact area by forming a curvature in a portion where the dielectric filling the sustain electrode contacts the partition wall, a force is applied to a local region of the upper end of the partition wall to prevent the partition wall from being damaged.

Second, by minimizing the breakage of the partition wall, it is possible to reduce the defects of the pixel.

Third, it is possible to secure a wide voltage margin to enable a stable discharge of the panel.

Fourth, the discharge surface is greatly expanded by implementing the discharge along the side of the discharge space.

Fifth, as the discharge electrode, the dielectric layer and the protective film layer filling the inner surface of the substrate facing the discharge space are not formed, the aperture ratio is greatly improved.

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

1A to 1C schematically illustrate a structure of a partition of a conventional plasma display panel.

1A is a top view,

1B is an enlarged perspective view of a portion of FIG. 1A;

FIG. 1C is another perspective view of an enlarged portion of FIG. 1A;

2 is a schematic diagram showing a state in which the discharge electrode is disposed according to an embodiment of the present invention,

3 is an exploded perspective view of a plasma display panel partially cut out according to an embodiment of the present invention;

4 is an exploded perspective view illustrating the discharge electrode of FIG. 3;

FIG. 5 is an enlarged cross-sectional view of a unit discharge cell in a state in which the panel of FIG. 3 is coupled; FIG.

<Brief description of symbols for the main parts of the drawings>

300 ... plasma display panel 310 ... front substrate

320 ... back substrate 330 ... address electrode

340 Dielectric Layer 350 Dielectric Wall

360 ... hold electrode 361 ... X electrode

362 ... Y electrode 370 ... protective layer

380 ... Bulk 390 ... Phosphor Layer

Claims (9)

A front substrate; A rear substrate disposed to face the front substrate; A dielectric wall disposed between the front and rear substrates and defining a discharge space together with the front and rear substrates; A partition wall disposed between the dielectric wall and the rear substrate and defining a discharge space together with the dielectric wall; A discharge electrode embedded in the dielectric wall and having first and second discharge electrodes disposed up and down along the circumference of the discharge space; It includes; red, green, blue phosphor layer applied in the partition wall, And a curvature portion is formed in a portion where the dielectric wall contacts the partition wall to reduce a contact area. The method of claim 1, And the dielectric wall is formed to face from the front substrate to the back substrate, and the ends of the dielectric walls have a predetermined curvature and are in contact with the ends of the partition walls. The method of claim 2, And an end portion of the dielectric wall contacting an end portion of the dielectric wall is a vertex of a curved portion. The method of claim 1, The portion where the dielectric wall and the partition contact each other satisfies Equation 1 below. <Equation 1> Here, C is the width of the portion where the dielectric wall and the partition contact, and A and B are the widths of the non-contact portion formed on both sides of the portion where the dielectric wall and the partition contact. The method of claim 1, And the first discharge electrode extends in one direction of the discharge space, and the second discharge electrode extends in a direction crossing the first discharge electrode. The method of claim 1, The first and second discharge electrodes are X and Y electrodes extending along one direction of the discharge space, and further comprising an address electrode extending in a direction crossing the first and second discharge electrodes. panel. The method of claim 6, The X and Y electrodes have a ladder structure electrically connected between adjacent electrodes in one direction, and the address electrode has a strip shape. The method of claim 6, And the address electrode is disposed between the rear substrate and the phosphor layer, and a dielectric layer is formed between the phosphor layer and the address electrode. The method of claim 1, And a passivation layer is further coated on an inner surface of the dielectric wall to increase secondary electron emission.