KR20080016042A - Plasma display panel - Google Patents

Abstract

A plasma display panel is provided to enhance light emitting efficiency, to reduce reflective luminance, and to improve a bright room contrast by forming complementary relationship among a glass filter, a front dielectric layer, and a rear substrate. A rear substrate(10) is disposed to be opposite to a front substrate(15) and is colored with a first color. An address electrode(11) is extended in a first direction on the rear substrate. A rear dielectric layer(12) is formed on the rear substrate in order to cover the address electrode. A barrier rib(13) is arranged between the front substrate and the rear substrate in order to define discharge cells. A phosphor layer(14) is formed on an inner surface of the discharge cells. A display electrode(16) is formed in a second direction crossing a first direction on the front substrate. A front dielectric layer(17) is formed on the front substrate in order to cover the display electrode. The front dielectric layer is colored with a second color. A glass filter(19) is arranged at the outside of the front substrate and is colored with a third color. The subtractive mixture relationship is formed in the first, second, and third colors.

Description

Plasma Display Panel {PLASMA DISPLAY PANEL}

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

FIG. 2 is a cross-sectional view taken along the line II-II of FIG. 1.

3 is a plan view illustrating an image display area of a plasma display panel according to an exemplary embodiment of the present invention.

4 is a view schematically showing the relationship between colors that appear when three primary colors of a color material overlap.

<Description of the symbols for the main parts of the drawings>

10: back substrate 11: address electrode

12: back dielectric layer 13: bulkhead

13a: horizontal partition member 13b: vertical partition member

14 phosphor layer 15 front substrate

16: display electrode 16a: scanning electrode

16b: sustain electrode 17 front dielectric layer

18: protective layer 19: glass filter

20: bus electrode 30: image display area

30a: first region 30b: second region

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display panel. More particularly, the present invention relates to a plasma display panel having low reflection brightness, high black ratio, and high luminous efficiency by adopting subtractive mixing.

In general, a plasma display panel uses ultraviolet (UV) rays emitted from a plasma obtained through gas discharge. This ultraviolet light excites the phosphor layer, and the excited phosphor layer generates visible light. The visible light has red (R), green (G), and blue (B) depending on the type of the phosphor layer, and the combination of them is realized.

As an example, an AC plasma display panel includes an address electrode on a rear substrate, and a dielectric layer covers the address electrode. In addition, a partition wall is formed in a stripe shape on the dielectric layer, and a phosphor layer is formed inside the partition wall.

The front substrate is provided spaced apart from the rear substrate by a predetermined distance, and the display electrodes, the dielectric layer, and the protective layer are sequentially formed on the front substrate. The display electrode is formed in a direction crossing the address electrode.

Discharge cells are formed at the intersections of the address electrodes on the rear substrate and the display electrodes on the front substrate, which are divided by partition walls. More than millions of unit discharge cells are arranged in a matrix or stripe form inside the plasma display panel.

In the plasma display panel, the principle of causing discharge in the discharge cells will be described in more detail. In order to cause the discharge between the sustain electrode and the scan electrode, a potential difference of a specific voltage or more is required therebetween, and the discharge voltage is started. It is called a firing voltage (Vf).

Once the scan voltage and the address voltage are applied to the scan electrode and the address electrode, the discharge is initiated between them to form a plasma in the discharge cell, and the electrons and ions constituting the plasma move toward the electrodes having opposite polarities. .

On the other hand, the plasma display panel is coated with a dielectric layer, so that most of the space charges transferred are accumulated in the dielectric layer having the opposite polarity, so that the net potential between the scan electrode and the address electrode is originally applied to the address voltage Va. It becomes lower, the discharge is weakened and the address discharge is extinguished.

A relatively small amount of electrons is accumulated on the sustain electrode, and a relatively large amount of ions are accumulated on the scan electrode. The charges accumulated in the dielectric layers covering the sustain electrodes and the scan electrodes form wall charges (Qw), and wall voltages (Vw) are formed between the sustain electrodes and the scan electrodes by these wall charges.

Subsequently, when the discharge sustain voltage Vs is applied to the sustain electrode and the scan electrode, the sum of the magnitudes of the discharge sustain voltage Vs and the wall voltage Vw (Vs + Vw) is the discharge start voltage Vf. If it is higher, sustain discharge occurs in the discharge cell. Ultraviolet (UV) generated at this time excites the phosphor layer, and the phosphor layer emits visible light. Visible light is transmitted to the outside of the plasma display panel through the front substrate.

On the other hand, when there is no address discharge between the scan electrode and the address electrode (that is, when the address voltage Va is not applied), wall charges do not accumulate between the sustain electrode and the scan electrode, and consequently, the sustain electrode and the scan electrode. There is no wall voltage in between.

At this time, only the discharge sustain voltage Vs applied to the sustain electrode and the scan electrode is formed in the discharge cell. Since the discharge sustain voltage is lower than the discharge start voltage Vf, no discharge occurs between the sustain electrode and the scan electrode.

Various attempts have been made to improve image quality in such plasma display panels. There are a method of improving the black-room ratio to improve the bright room contrast, a method of reducing the reflected luminance to easily implement an image, and a method of improving the luminance by increasing the luminous efficiency.

In particular, a separate black layer may be formed between the front substrate and the rear substrate in order to improve the black portion, but since the configuration of the high-definition panel that can be contained therein should be limited, the above-described separate configuration is excluded. There is a need for a technique that can improve black fraction and clear contrast with minimal or minimal growth.

The present invention has been made to solve the above problems, and an object thereof is to provide a plasma display panel having high luminous efficiency, low reflectance brightness, and improved black ratio and clear room contrast.

In order to achieve the above object, a plasma display panel according to the present invention includes a rear substrate facing a front substrate and colored in a first color, an address electrode formed to extend in the first direction on the rear substrate, and covering the address electrode; A back dielectric layer formed on the back substrate, a partition wall partitioning respective discharge cells between the front substrate and the back substrate, a phosphor layer formed inside the discharge cell, and a second direction crossing the first direction on the front substrate; A display electrode formed on the front substrate and covering the display electrode, the front dielectric layer colored in a second color, and a glass filter disposed outside of the front substrate and colored in a third color; The one color, the second color, and the third color are each subtracted from each other.

In addition, in the plasma display panel according to the present invention, a color in which any two selected colors of the first color, the second color, and the third color are mixed is preferably in a complementary color relationship with the other color. In addition, the first color, the second color and the third color is preferably any one of the colors selected from among the three primary colors of the magenta (Cagenta), cyan (Yellow) and the yellow (Yellow) series of colors, respectively. .

In the plasma display panel according to the present invention, the front substrate is preferably a colorless transparent substrate. In addition, the partition wall is preferably made of a colorless transparent partition wall material. In addition, the back dielectric layer is preferably made of a colorless transparent dielectric material.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and like reference numerals designate like elements throughout the specification.

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

Referring to FIG. 1, the plasma display panel according to the present embodiment includes a rear substrate 10 and a front substrate 15 that are disposed to face each other. A partition 13 is formed between the rear substrate 10 and the front substrate 15, and these partitions a plurality of discharge cells.

The partition wall 13 includes a vertical partition wall member 13b formed long in a first direction (y-axis direction in the drawing), and a horizontal partition wall member 13a formed long in a second direction (x-axis direction in the drawing). . As shown, the horizontal partition member 13a and the vertical partition member 13b are perpendicular to each other. In an embodiment of the present invention, the horizontal partition wall member 13a and the vertical partition wall member 13b partition discharge cells in a lattice form.

There are various forms and structures of the discharge cells, and the discharge cells partitioned by the partition wall 13 may be formed in various forms such as a stripe or a delta pattern in addition to the grid pattern described above.

Each of the discharge cells forms a minimum unit for displaying an image, and a plurality of discharge cells are formed to form one pixel. In addition, a phosphor layer 14 is formed in the discharge cells to absorb ultraviolet rays obtained through plasma gas discharge and emit visible light for each color.

The red (R), green (G), and blue (B) discharge cells are respectively formed according to the type of the phosphor layer 14, and the red discharge cell, the green discharge cell, and the blue discharge cell form one pixel. Achieve. In this case, the phosphor layer 14 may include a white powder having a high reflectance in order to improve luminance.

Each discharge cell in which the phosphor layer 14 is formed is filled with a discharge gas (eg, a mixed gas including xenon (Xe), neon (Ne), etc.) to cause plasma discharge.

The address electrode 11 and the display electrode 16 are provided on the back substrate 10 and the front substrate 15 facing each other. The display electrode 16 includes a scan electrode 16a and a sustain electrode 16b, and the scan electrode 16a and the sustain electrode 16b are formed on the front substrate 15 in a second direction (x-axis direction in the drawing). Extends alongside.

The address electrode 11 and the display electrode 16 are arranged to cross each other. The address electrode 11 and the scan electrode 16a generate an address discharge to select a discharge cell, and after the address discharge, generate a sustain discharge to the sustain electrode 16b and the scan electrode 16a, respectively, to the selected discharge cell. Implement

First, the address electrode 11 extends in the first direction (y-axis direction in the figure) on the rear substrate 10 and is arranged side by side in a stripe shape along the vertical partition member 13b.

In addition, the address electrode 11 is embedded in the back dielectric layer 12. The back dielectric layer 12 protects the address electrode 11 from discharge and easily accumulates electric charges around the address electrode 11. Be sure to In addition, a partition 13 is formed on the rear dielectric layer 12, and the partition 13 partitions respective discharge cells.

The front dielectric layer 17 covers the scan electrode 16a and the sustain electrode 16b, and during plasma discharge, the front dielectric layer 17 protects the display electrode 16 from discharge and allows charge to accumulate around the electrode. A protective layer 18 is further formed on the front dielectric layer 17, and the protective layer 18 protects the front dielectric layer 17 from discharge generated in the discharge cell.

The protective layer 18 not only protects the front dielectric layer 17, but also lowers the discharge start voltage by increasing the secondary electron emission coefficient. In addition, the protective layer 18 may be formed of an MgO film that easily transmits visible light.

FIG. 2 is a cross-sectional view taken along the line II-II of FIG. 1.

The display electrode 16 includes a scan electrode 16a and a sustain electrode 16b, and the bus electrode 20 is formed long on the lower surface of the display electrode 16.

In general, the bus electrode 20 is made of a conductive metal material so as to smoothly supply voltage. At this time, the bus electrode 20 made of metal has a narrow width so as to increase the transmittance of visible light generated in the discharge cell. In addition, it may be installed adjacent to the horizontal partition member (13a) for partitioning the discharge cell or along the upper surface of the horizontal partition member (13a).

The scan electrode 16a includes a transparent material such as indium tin oxide (ITO) so as to increase the transmittance of visible light. In addition, in the exemplary embodiment of the present invention, the display electrodes 16 are continuously formed, but in other embodiments, the display electrodes 16 may be formed separately in the respective discharge cells.

The glass filter 19 is formed on the outer surface of the front substrate 15. The glass filter 19 absorbs a small amount of infrared rays emitted from the discharge cell. In addition, by absorbing the external light emitted to the front substrate 15 to reduce the reflected brightness of the plasma display panel.

In the plasma display panel, near-infrared rays and electromagnetic waves of 800-900 nanometers are emitted. Such near-infrared rays are similar to infrared rays used in a remote controller, which may cause a malfunction of the device.

In order to solve this problem, a glass filter 19 is provided. In addition, the glass filter 19 absorbs external light to reduce the reflected luminance. Formation methods include a method of forming a transparent conductive film on the front substrate 15, a method of applying a resin, and the like, and a method of attaching a film. Characteristics required for the glass filter 19 include near infrared absorptivity, reflectance, electromagnetic wave blocking rate, abrasion resistance, heat resistance, and the like.

According to an embodiment of the present invention, the glass filter 19 is colored with cyan, the front dielectric layer 17 is colored with magenta, and the back substrate 10 is colored with yellow. . In addition, the back dielectric layer 12, the partition 13, and the front substrate 15 are preferably not colored.

When the first color of the glass filter 19, the second color of the front dielectric layer 17, and the third color of the back dielectric layer 12 are subtracted or superimposed, they have a dark color such as black. In particular, the colors of cyan, magenta, and yellow overlap or become black. In particular, dark colors such as black have a strong absorbing property. Therefore, light emitted from the outside of the plasma display panel is easily absorbed.

In summary, the reflection brightness of the plasma display panel is reduced, the black portion is increased, and the bright room contrast is increased.

In the embodiment of the present invention, it is preferable that the partition wall 13 and the back dielectric layer 12 are not colored. In addition, they may be formed of the same material. Therefore, it can form in the same process and there exists an effect which a manufacturing process becomes simple.

In addition, since the coloring pigment does not enter the partition 13, the ratio of TiO 2, which is a strength enhancer, is relatively high, and thus the strength of the partition 13 is increased to damage the phosphor layer 14 or cause defects in the discharge cells. It solves the problems and at the same time extends the life of the plasma display panel.

In addition, the partition wall 13 and the rear dielectric layer 12 that are not colored absorb less visible light formed in the discharge cells, thereby increasing the luminous efficiency of the plasma display panel.

3 is a plan view illustrating an image display area of a plasma display panel according to an exemplary embodiment of the present invention.

Hereinafter, a plasma display panel according to an exemplary embodiment of the present invention will be described with reference to the accompanying drawings, and the same reference numerals are used for the same or similar parts as those of FIGS. 1 and 2, and repeated descriptions thereof will be omitted.

As shown in FIG. 3, the plasma display panel has an image display area 30. For convenience of description, the image display area 30 shows only a part of the entire area.

The image display area 30 includes a first area 30a and a second area 30b. The first region 30a is a region where the glass filter 19 and the front dielectric layer 17 mainly overlap, and the second region 30b is a glass filter 19, the front dielectric layer 17 and the back substrate 10. It is mainly an overlapping area.

Accordingly, the first region 30a is a region in which cyan and magenta are subtracted and mixed, and the second region 30b is a mixture in which cyan, magenta and yellow are subtracted and mixed. Area.

In particular, since the second region 30b has a black color, the second region 30b easily absorbs light emitted from the outside. Therefore, the reflected luminance of the plasma display panel is reduced, and the black fraction is increased.

On the other hand, since the visible light generated in the discharge cell is easily reflected by the back substrate 10 colored in yellow, the luminous efficiency is increased. This is because yellow has a strong property of reflecting visible light.

In the embodiment of the present invention, the glass filter 19 is colored magenta, the front dielectric layer 17 is colored cyan, and the back dielectric layer 12 is colored yellow. However, there is no particular limitation on the kind of colored colors.

In order to increase the black ratio and to reduce the reflection luminance, it may be preferable that the colors are complementary colors. In addition, the back substrate is preferably colored with a color that easily reflects visible light.

4 is a view schematically showing the relationship between colors that appear when three primary colors of a color material overlap.

The three primary colors of the colors are magenta, yellow and cyan, which are red, green, blue and black when these colors are mixed or overlapped. .

Magenta is slightly blueish red (purple), cyan is slightly greenish blue (blue-green), and yellow is yellow. By mixing the three primary colors of these colors or by overlapping filters, you can create different colors. In addition, Blue is indigo blue with a blue series.

As shown in FIG. 4, when Yellow and Magenta overlap, Red becomes red, and when Yellow and Cyan overlap, Green becomes green, and Cyan and Magenta overlap. Overlapping magenta is blue. In addition, if Green and Magenta overlap, it becomes Black, and if Blue and Yellow overlap, it becomes Black. If Red and Cyan overlap, it becomes black. It becomes (Black).

Colors such as magenta, yellow and cyan are called primary colors. In addition, the color which subtracts and mixes arbitrary two colors among primary colors is called secondary color. That is, Red, Green, and Blue are called secondary colors, and these colors are called three primary colors of color.

It is said that the relationship between the colors being mixed or overlapping becomes the achromatic color (White, Gray, Black). Green has a complementary color relationship with Magenta, Yellow has a complementary color relationship with Blue, and Red has a complementary color relationship with Cyan. In addition, magenta, yellow, and cyan are black when overlapped or mixed together, and thus they may be said to be complementary to each other.

Even if the color is not complementary, the subtractive color of the complementary color gives a dark color close to black.

As described above, when the first color of the glass filter 19, the second color of the front dielectric layer 17, and the third color of the back dielectric layer 12 are subtracted or overlapped, they have a dark color such as black. In addition, the first color, the second color, and the third color may be formed of three primary colors (Magenta, Cyan, Yellow) of different colorants, and all three primary colors of the colorant are primary colors.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications or changes can be made within the scope of the claims and the detailed description of the invention and the accompanying drawings. It goes without saying that it belongs to the scope of the present invention.

As described above, according to the plasma display panel according to the present invention, the glass filter, the front dielectric layer, and the back substrate are colored to have a complementary color relationship with each other, whereby the reflection luminance is lowered, the black ratio is increased, and the contrast contrast is increased. have.

In addition, the rear substrate has an effect of increasing luminous efficiency by coloring a color that easily reflects visible light such as yellow.

In addition, the non-colored partition wall has a stronger strength than the colored partition wall, thereby preventing damage to the discharge cell and the phosphor layer in advance, thereby preventing abnormal discharge, and extending the life of the plasma display panel.

Claims (6)

A back substrate facing the front substrate and colored in a first color; An address electrode formed on the rear substrate to extend in a first direction; A back dielectric layer covering the address electrode and formed on the back substrate; Barrier ribs that partition respective discharge cells between the front substrate and the rear substrate; A phosphor layer formed inside the discharge cell; A display electrode formed on the front substrate to extend in a second direction crossing the first direction; A front dielectric layer covering the display electrode and formed on the front substrate and colored in a second color; And A glass filter disposed outside the front substrate and colored in a third color, And the first, second and third colors are subtracted and mixed with each other. According to claim 1, And a color in which any two selected ones of the first color, the second color, and the third color are mixed is complementary to the other color. According to claim 1, The first color, the second color, and the third color may be any one of different colors selected from magenta, cyan, and yellow series colors, which are three primary colors of the colorant. According to claim 1, And the front substrate is a colorless transparent substrate. According to claim 1, And the partition wall is made of a colorless transparent partition material. According to claim 1, And the back dielectric layer is made of a colorless transparent dielectric material.

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