KR100747341B1 - Plasma Display Panel - Google Patents

Abstract

The present invention relates to a plasma display panel capable of driving at low voltage while improving efficiency by lowering discharge voltage.

In the plasma display panel according to the present invention, a plasma display panel having a plurality of address electrodes to which data for selecting a cell is supplied, wherein the address electrode protrudes toward a discharge cell, has a protrusion for inducing electric field concentration. do.

Accordingly, the address electrode having the protruding portion lowers the discharge voltage, thereby improving efficiency and driving at a low voltage.

Description

Plasma Display Panel             

1 is a perspective view showing a conventional three-electrode AC surface discharge PDP.

FIG. 2 is a sectional view of the PDP shown in FIG. 1. FIG.

3 is a cross-sectional view showing a PDP proposed to improve the problem of the PDP shown in FIG.

4 is a perspective view showing a PDP according to a first embodiment of the present invention.

FIG. 5 is a sectional view of the PDP shown in FIG. 4; FIG.

FIG. 6 is a plan view of the PDP shown in FIG. 4; FIG.

7 to 12 are perspective views illustrating protrusions according to various embodiments of the present disclosure shown in FIG. 4.

13 is a cross-sectional view illustrating a PDP according to a second embodiment of the present invention.

<Description of Symbols for Main Parts of Drawings>

10, 40: upper substrate 12, 42: lower substrate

14, 44 scanning / holding electrode 16, 46: sustaining electrode

18, 48: upper dielectric layer 20, 50: protective film

22, 52: address electrode 24, 56: lower dielectric layer                 

26, 58: partition 28, 60: phosphor layer

54, 65; projection part

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display, and more particularly, to a plasma display panel capable of driving at low voltage while improving efficiency by lowering discharge voltage.

Recently, a plasma display panel (hereinafter referred to as "PDP"), which is easy to manufacture a large panel, has attracted attention as a flat panel display device. The PDP normally displays an image by adjusting the discharge period of each pixel according to the digital video data. As such a PDP, an AC type PDP having three electrodes and driven by an AC voltage is typical.

1 is a perspective view illustrating a discharge cell of an AC PDP, and FIG. 2 is a cross-sectional view of the discharge cell shown in FIG. 1.

1 and 2, a PDP discharge cell includes an upper plate having sustain electrode pairs 14 and 16, an upper dielectric layer 18, and a passivation layer 20 sequentially formed on an upper substrate 10, and a lower substrate ( 12, a lower plate having an address electrode 22, a lower dielectric layer 24, a partition wall 26, and a phosphor layer 28 sequentially formed thereon is provided.                         

The upper substrate 10 and the lower substrate 12 are spaced in parallel by the partition wall. Each of the sustain electrode pairs 14 and 16 has a relatively wide width and transparent electrodes 14A and 16A made of transparent electrode material (ITO) for transmitting visible light, and a relatively narrow width and transparent electrodes 14A and 16A. In order to compensate for the resistive components of the metal electrodes 14B and 16B. The sustain electrode pairs 14 and 16 are composed of scan / sustain electrodes and sustain electrodes. The scan signal for panel scanning and the sustain signal for discharging sustain are mainly supplied to the scan / hold electrode 14, and the sustain signal is mainly supplied to the sustain electrode 16. Charges accumulate in the upper dielectric layer 18 and the lower dielectric layer 24. The protective film 20 prevents damage to the upper dielectric layer 18 by sputtering, thereby increasing the lifetime of the PDP and increasing the emission efficiency of secondary electrons. As the protective film 20, magnesium oxide (MgO) is usually used. The address electrode 22 is formed to cross the sustain electrode pairs 14 and 16. The address electrode 22 is supplied with a data signal for selecting cells to be displayed. The partition wall 26 is formed in parallel with the address electrode 22 to prevent ultraviolet rays generated by the discharge from leaking to adjacent cells. The phosphor layer 28 is applied to the surfaces of the lower dielectric layer 24 and the partition wall 26 to generate visible light of any one of red, green, and blue. Then, an inert gas for gas discharge is injected into the discharge space therein.

The PDP cell of this structure is selected by the counter discharge between the address electrode 22 and the scan / hold electrode 14, and then maintains the discharge by the surface discharge between the sustain electrode pairs 14 and 16. In the PDP cell, the fluorescent substance 28 emits light by ultraviolet rays generated during sustain discharge, so that visible light is emitted outside the cell. As a result, the PDP having cells displays an image. In this case, the PDP implements a gray scale required for displaying an image by adjusting the discharge sustain period of the cell, that is, the number of sustain discharges, according to the video data.

The AC surface discharge type PDP is driven by being divided into a plurality of subfields to express the gray level of the image. In each subfield period, gray scale display is performed by performing light emission in a number of times proportional to the weight of video data. do. For example, when an image is displayed in 256 gray scales using 8-bit video data, one frame display period (for example, 1/60 second = about 16.7 msec) in each discharge cell is divided into eight subfields SF1 to SF1. SF8). Each subfield SF1 to SF8 is further divided into a reset period, an address period and a sustain period, and 1: 2: 4: 8:... The weight is given at the ratio of 128. Here, the reset period is a period for initializing the discharge cells, the address period is a period during which selective address discharge occurs according to the logic value of the video data, and the sustain period is such that discharge is maintained in the discharge cells in which the address discharge has occurred. It is a period. The reset period and the address period are equally assigned to each subfield period.

This PDP should supply a high voltage to the sustain electrode pairs 14 and 16 during sustain discharge. A tip-shaped protrusion 15 is formed on the sustain electrode pairs 14 and 16 to lower the discharge voltage of the high voltage supplied to the sustain electrode pairs 14 and 16.

Referring to FIG. 3, each of the sustain electrode pairs 14 and 16 of the PDP has a wide width and is made of transparent electrode material (ITO) to transmit visible light. The sustain electrode pairs 14 and 16 are composed of scan / sustain electrodes and sustain electrodes. Projections 15 are formed on the scan / sustain electrodes and sustain electrodes 14, 16, respectively.

The protrusion 15 has a tip shape having a size of 10 to 100 μm and a height of 10 to 30 μm. As the protrusions 15 are formed on the scan / hold electrode and sustain electrodes 14 and 16 of the conventional three-electrode PDP, the discharge area between the electrodes is increased. Accordingly, the discharge voltage required for the sustain discharge becomes low and the discharge becomes easy.

However, since the tip-shaped protrusions 15 are formed only on the scan / sustain electrodes and sustain electrodes 14, 16, the problem of high discharge voltage during address discharge remains.

Accordingly, an object of the present invention is to provide a plasma display panel capable of driving at low voltage while improving efficiency by lowering discharge voltage by an address electrode having a protrusion.

In order to achieve the above object, a plasma display panel according to the present invention has a plurality of address electrodes to which data for selecting a cell is supplied, wherein the address electrodes protrude toward discharge cells to induce electric field concentration. It is characterized by having a protrusion for.

Other objects and advantages of the present invention in addition to the above object will be apparent from the description of the preferred embodiment of the present invention with reference to the accompanying drawings.                     

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to FIGS. 4 to 7.

4 and 5, in the PDP according to the first embodiment of the present invention, the protrusion 54 is formed on the address electrode 52.

The lower substrate 42, the sustain electrode pairs 44 and 46, and the upper dielectric layer, in which the address electrode 52, the lower dielectric layer 56, the partition 58, and the phosphor layer 60 in which the protrusion 54 is formed, are sequentially formed. 48 and a protective film 50 are provided with the upper substrate 40 formed sequentially.

The upper substrate 40 and the lower substrate 42 are spaced apart in parallel by the partition 58. Each of the sustain electrode pairs 44 and 46 has a relatively wide width and has a relatively narrow width with the transparent electrodes 44A and 46A made of transparent electrode material (ITO) to transmit visible light. In order to compensate for the resistive components, the metal electrodes 44B and 46B are formed. The sustain electrode pairs 44 and 46 are composed of scan / sustain electrodes and sustain electrodes. The scan signal for panel scanning and the sustain signal for discharge sustaining are mainly supplied to the scan / hold electrode 44, and the sustain signal is mainly supplied to the sustain electrode 46. Charges are accumulated in the upper dielectric layer 48 and the lower dielectric layer 56. The passivation layer 50 prevents damage to the upper dielectric layer 48 by sputtering, thereby increasing the lifetime of the PDP and increasing the emission efficiency of secondary electrons. As the protective film 50, magnesium oxide (MgO) is usually used.

The address electrode 52 is formed to cross the sustain electrode pairs 44 and 46. The address electrode 52 is supplied with a data signal for selecting cells to be displayed.                     

One protrusion 54 of the address electrode 52 is formed in a cone shape for each discharge cell. The conical protrusion 54 has a shape of any one of a triangular prism, a cylindrical shape, and a square prism as shown in FIGS. 7 to 9. In addition, as shown in FIGS. 10 to 12, the protrusion 54 of the address electrode 52 is formed in a stripe shape and has a cross-sectional structure of a rhombus, a triangle, and a quadrangle in order to concentrate an electric field. Meanwhile, the address electrode 52 may be formed at an intersection with the scan / sustain electrode 44 to lower the discharge voltage required for the address discharge.

Since the height of the partition wall 58 is 150 to 200 μm and the height of the address electrode 52 is 5 to 10 μm, it is necessary to secure a discharge space for discharging, between the sustain electrode pairs 44 and 46 and the address electrode 52. Since the spacing affects the discharge voltage, an appropriate height of the protrusion 54 should be selected in consideration of this. That is, the height of the protrusion 54 is about 20 ~ 80㎛.

The protrusion 54 is formed of silver (Ag) paste or silver (Ag) metal, which is the same material as that of the address electrode 52. The protrusion 54 is formed by an etching method or by direct printing.

In general, when looking at the electric field formed around the electrode, it can be seen that the electric field is concentrated at the point such as the sharp edge. This principle causes the electric field to be concentrated around the protrusion 54. Therefore, the voltage required for discharge during address discharge can be lowered and discharge efficiency is improved. In addition, since the electrode area is enlarged by the protrusion 54, the discharge area is increased. As a result, the address discharge becomes easy and the voltage required for the discharge during the address discharge decreases.

The partition 58 is formed in parallel with the address electrode 52 to prevent the ultraviolet rays generated by the discharge from leaking to the adjacent cells. The phosphor layer 60 is applied to the surfaces of the lower dielectric layer 56 and the partition wall 58 to generate visible light of any one of red, green, and blue. Then, an inert gas for gas discharge is injected into the discharge space therein.

The PDP cell of this structure is selected by the counter discharge between the address electrode 52 and the scan / sustain electrode 44 and then sustains the discharge by the surface discharge between the sustain electrode pairs 44 and 46. In the PDP cell, the fluorescent substance 60 emits light by ultraviolet rays generated during sustain discharge, so that visible light is emitted to the outside of the cell. As a result, the PDP having cells displays an image. In this case, the PDP implements a gray scale required for displaying an image by adjusting the discharge sustain period of the cell, that is, the number of sustain discharges, according to the video data.

The PDP according to the present invention is driven by being divided into a plurality of subfields to express a gray level of an image, and in each subfield period, grayscale display is performed by performing light emission in a number of times proportional to the weight of video data. It becomes. For example, when an image is displayed in 256 gray scales using 8-bit video data, one frame display period (for example, 1/60 second = about 16.7 msec) in each discharge cell is divided into eight subfields SF1 to SF1. SF8). Each subfield SF1 to SF8 is further divided into a reset period, an address period and a sustain period, and 1: 2: 4: 8:... The weight is given at the ratio of 128. Here, the reset period is a period for initializing the discharge cells, and the address period is a period for causing selective address discharge according to the logic value of the video data. During this address discharge, an electric field is concentrated around the protrusion 54 of the address electrode 52. As a result, the voltage required for discharge during address discharge can be lowered and discharge efficiency is improved.

Referring to FIG. 13, in the PDP according to the second embodiment of the present invention, a first protrusion 54 is formed on the address electrode 52 and a second protrusion 65 is formed on the sustain electrode pairs 64 and 66. do.

The lower substrate 42 on which the address electrode 52, the lower dielectric layer 56, the partition 58, and the phosphor layer 60 in which the first protrusion 54 is formed is sequentially formed, and the second protrusion 65 are formed therein. The upper substrate 40 includes the electrode pairs 64 and 66, the upper dielectric layer 48, and the passivation layer 50 sequentially formed.

The upper substrate 40 and the lower substrate 42 are spaced apart in parallel by the partition 58. Each of the sustain electrode pairs 64 and 66 has a wide width and is made of transparent electrode material (ITO) to transmit visible light. The sustain electrode pairs 64 and 66 are composed of scan / sustain electrodes and sustain electrodes. The scan signal for panel scanning and the sustain signal for discharge holding are mainly supplied to the scan / hold electrode 64, and the sustain signal is mainly supplied to the sustain electrode 66. The second protrusions 65 formed on the scan / sustain electrodes and the sustain electrodes 64 and 66, respectively, have a cone shape with a size of 10 to 100 μm and a height of 10 to 30 μm. The discharge area between the scan / sustain electrode and sustain electrodes 64 and 66 is increased by the second protrusion 65. Accordingly, the discharge voltage required for the sustain discharge is lowered, which facilitates the discharge.

Charges are accumulated in the upper dielectric layer 48 and the lower dielectric layer 56. The passivation layer 50 prevents damage to the upper dielectric layer 48 by sputtering, thereby increasing the lifetime of the PDP and increasing the emission efficiency of secondary electrons. As the protective film 50, magnesium oxide (MgO) is usually used.

The address electrode 52 is formed to cross the sustain electrode pairs 64 and 66. The address electrode 52 is supplied with a data signal for selecting cells to be displayed.

One first protrusion 54 of the address electrode 52 is formed in a cone shape for each discharge cell. The first protrusion 54 may have any one of a triangular prism, a cylindrical shape, and a square pillar. In addition, the first protrusion 54 is formed in a stripe shape and has a cross-sectional structure of a rhombus, a triangle, and a quadrangle in order to concentrate an electric field. Here, the address electrode 52 may be formed at an intersection with the scan / sustain electrode 64 to lower the discharge voltage required for the address discharge.

Since the height of the partition wall 58 is 150 to 200 μm and the height of the address electrode 52 is 5 to 10 μm, it is necessary to secure a discharge space for discharging, and between the sustain electrode pairs 64 and 66 and the address electrode 52. Since the spacing affects the discharge voltage, an appropriate height of the first protrusion 54 should be selected in consideration of this. That is, the height of the first protrusion 54 is about 20 ~ 80㎛.

The first protrusion 54 is formed of silver (Ag) paste or silver (Ag) metal, which is the same material as that of the address electrode 52. The first protrusion 54 is formed by an etching method or by direct printing.

In general, when looking at the electric field formed around the electrode, it can be seen that the electric field is concentrated at the point such as the sharp edge. This principle causes the electric field to be concentrated around the first and second protrusions 54, 65. Therefore, the voltage required for discharge during sustain discharge and address discharge can be lowered, and discharge efficiency is improved. In addition, since the electrode area is enlarged by the first and second protrusions 54 and 65, the discharge area is increased. As a result, the sustain discharge and the address discharge become easy, and the voltage required for the discharge during the sustain discharge and the address discharge decreases.

As described above, in the plasma display panel according to the present invention, since the protrusion area is formed in the address electrode, the size of the discharge area increases, so that the discharge area is widened. Accordingly, the plasma display panel according to the present invention can be driven at a low voltage by lowering the discharge voltage required for address discharge. Therefore, the plasma display panel according to the present invention can improve the efficiency.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the technical spirit of the present invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification but should be defined by the claims.

Claims (7)

A plasma display panel having a plurality of address electrodes supplied with data for selecting a cell, And the address electrode protrudes toward the discharge cell and has a protrusion for inducing electric field concentration. The method of claim 1, And the protrusion of the address electrode is any one of a conical shape, a cylindrical shape, a square pillar, and a triangular shape. The method of claim 1, And a protrusion portion of the address electrode is formed along the address electrode in a stripe shape. The method of claim 3, wherein And a cross section of a protrusion of the address electrode cut in a direction crossing the address electrode is one of a rhombus, a triangle, and a quadrangle. The method of claim 1, And a height of the protruding portion of the address electrode is substantially 20 µm or more and 80 µm or less. The method of claim 1, An upper substrate opposing the lower substrate on which the address electrode is formed and a discharge space therebetween; And a sustain electrode pair formed on the upper substrate and having a protrusion for concentrating an electric field. The method of claim 6, And a protrusion of the address electrode is formed at an intersection of the scan electrodes of the sustain electrode pair.

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