KR20080018399A - Plasma display panel - Google Patents

Abstract

A plasma display panel is provided to reduce a halation effect by using a protective layer colored with a dark color. A front substrate(15) is arranged in a constant interval from a rear substrate(10). An address electrode(11) is extended in a first direction on the rear substrate. A barrier rib(13) is formed in a space between the front and rear substrates in order to define discharge cells. The barrier rib is colored with a first color. A display electrode(16) is extended in a second direction crossing the first direction. A front dielectric layer(17) is formed to cover the display electrode. The front dielectric layer is colored with a second color. A protective layer(18) is formed to cover a front dielectric layer and is colored with a third color. A filter(111) is formed on an outer surface of the front substrate. The filter includes a light guide(111a) having a light receiving surface and a light transmitting surface, and an external light reflection prevention member(111b) adjacent to the light guide. The external light reflection prevention member is colored with a fourth color. The subtraction mixture relationship is formed between three or more colors selected from the first to fourth colors.

Description

Plasma Display Panel {PLASMA DISPLAY PANEL}

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

FIG. 2 is a cross-sectional view taken along 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: sustain electrode

16b: scanning electrode 16c: bus electrode

17: front dielectric layer 18: protective layer

19: discharge cell 20: incident surface

21: Output screen 30: Image display area

30a: first region 30b: second region

30c: third region 111: filter

111a: light guide 111b: external light reflection preventing member

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 adopting subtractive mixing, which has high luminous efficiency and improved black ratio and clear room contrast.

The plasma display panel forms a plasma through a discharge phenomenon. Ultraviolet (UV) light emitted from the plasma excites the phosphor layer, and an image is realized by using visible light of red (R), green (G), and blue (B) colors generated in the phosphor layer.

The plasma display panel can easily realize a large screen, and because it is a self-luminous device such as a cathode ray tube (CRT), not only has good color reproducibility but also has a large viewing angle, so that the image display ability is excellent. In addition, the plasma display panel has a strength in terms of productivity and cost since the manufacturing method is simpler than liquid crystal display (LCD).

The plasma display panel may be classified into a direct current type (DC) and an alternating current type (AC) according to its discharge type. The DC plasma display panel has a structure in which electrodes are exposed to a discharge space, and charges are directly transferred between corresponding electrodes.

In the AC plasma display panel, an electrode is covered with a dielectric layer, and discharge is performed by wall charge. In recent years, durable AC plasma display panels have become mainstream.

In addition, the plasma display panel may be classified into a facing discharge type and a surface discharge type according to the arrangement of the electrodes. On the other hand, the opposite discharge type plasma display panel has a structure in which display electrodes are provided on the front substrate and the rear substrate, respectively, and discharge is formed in the direction of the rear substrate from the front substrate. On the other hand, the surface discharge plasma display panel has a structure in which display electrodes are arranged on the same substrate, and discharge occurs on one plane of the substrate.

The characteristics of the aforementioned counter-discharge plasma display panel are that the luminous efficiency is high and that the phosphor layer is easily degraded by the plasma. For this reason, surface-discharge type plasma display panels have become mainstream in recent years.

In a plasma display panel having an AC type surface discharge structure which is most commonly used, an address electrode is formed 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 to partition a discharge cell, and a phosphor layer is formed on the discharge cell. The phosphor layer is excited by ultraviolet rays and emits red (R), green (G), and blue (B) visible light.

Display electrodes are formed on the side of the front substrate facing the rear substrate, and a dielectric layer and a protective layer are sequentially formed. The display electrode is made of indium tin oxide (ITO) and the protective layer is made of MgO and a material, and each of them easily transmits visible light.

The display electrode is formed to cross the address electrode of the rear substrate. In addition, the display electrode includes a transparent electrode and a bus electrode, and the transparent electrode has high electrical resistance. Meanwhile, the metal bus electrode formed along the display electrode has low electrical resistance. The width of the bus electrode is formed as narrow as possible so as not to block much visible light generated in the discharge cell.

The discharge cells are formed in a matrix or stripe form in the plasma display panel. These discharge cells are partitioned by partition walls, and discharge cells are formed at the intersections of the display electrodes of the front substrate and the address electrodes of the rear substrate.

Such a plasma display panel selects a discharge cell using the storage characteristics of wall charges, generates a discharge in the selected discharge cell, and combines them appropriately to implement an image.

In particular, in an external bright condition, that is, a bright room condition, external light is incident to the inside of the panel, and the light generated from the discharge cell overlaps the external light. As a result, Bright Room Contrast is lowered and the image display capability of the plasma display panel is lowered.

Meanwhile, various attempts have been made to improve the image display capability of the aforementioned plasma display panel. There is a method of increasing the black ratio to reduce reflection brightness and improving bright room contrast and a method of increasing the luminous efficiency to improve the brightness of the panel.

Referring to the application number 10-2004-0029176 of the Korean Patent Application Publication, a light guide and an external light reflection preventing member are formed on the front substrate. The light guide serves to focus and emit light generated by the discharge. The light guide has an incident surface to which light is incident and an exit surface to which light is emitted, and the area of the exit surface is larger than that of the entrance surface.

On the other hand, the external light reflection preventing member easily absorbs light emitted from the outside to reduce the reflected brightness of the plasma display panel. However, there is a limit in reducing the reflection brightness of the panel and increasing the bright room contrast only by the external light reflection preventing member.

A black layer is formed in a non-discharge region such as an upper surface of the partition wall, and the black layer easily absorbs light emitted from the outside, thereby reducing reflection brightness and increasing black ratio of the plasma display panel, thereby improving clear room contrast. However, in order to form the black layer, a separate process must be added, and thus there is a problem in that production cost increases and production efficiency decreases.

On the other hand, when the partition wall is colored, the light emitted from the outside of the plasma display panel is absorbed by the partition wall, thereby reducing the reflection brightness and simultaneously improving the black ratio and the bright room contrast.

However, the main component of the bulkhead is low-melting powder glass, and a small amount of organic solvent, resin, and various additives are added to the bulkhead. If a colored pigment or a coloring material is added to the bulkhead to color the bulkhead, the bulkhead is not colored and the bulkhead is not. The component ratio of is different.

For example, the colored bulkheads are reduced in strength due to the pigmented pigment. Therefore, there is a problem that the partition wall is easily broken. In addition, even if the partition wall is easily colored, there is a limit in reducing the reflection brightness and increasing the black ratio of the plasma display panel.

The present invention was devised to solve the above problems, and an object of the present invention is to color the partition wall with the first color, the front dielectric layer with the second color, the protective layer with the third color, The external light antireflection member is colored with a fourth color to provide a plasma display panel with high luminous efficiency and improved black ratio and bright room contrast.

A plasma display panel according to an exemplary embodiment of the present invention may include a front substrate disposed opposite to a rear substrate at an interval, an address electrode formed to extend in a first direction on the rear substrate, and formed in a space between the front substrate and the rear substrate. Partitioning the plurality of discharge cells, the partition wall colored in a first color, the display electrode extending in a second direction crossing the first direction, the front dielectric layer covering the display electrode and colored in a second color And a filter formed on an outer surface of the front substrate and a protective layer covering the front dielectric layer and colored in a third color, wherein the filter includes an incidence surface and an emission surface through which light formed in the discharge cell passes; And the light guide and the light guide having an area of the incident surface wider than that of the exit surface, and are colored in a fourth color. Comprises a light anti-reflection member and said first color, second color, third color and the fourth is in at least three colors are each of different colors and the subtractive color mixing between selected ones of the colors.

In addition, in the plasma display panel according to an embodiment of the present invention, a color in which any two colors of at least three colors selected from the first color, the second color, the third color, and the fourth color are mixed is displayed as the other color and the complementary color. In a relationship. In addition, the fourth color colored on the protective layer is preferably lower in brightness than the other colors. In addition, it is preferable that the second color colored on the barrier is higher in brightness than the other colors.

In addition, the plasma display panel according to the embodiment of the present invention, each of the at least three colors selected from the first color, the second color, the third color and the fourth color magenta (Magenta) and the three primary colors of the colorant and It is preferable that the color is one selected from among the colors of cyan and yellow series.

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.

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.

1 is a partial perspective view of a plasma display panel according to an embodiment of the present invention. FIG. 2 is a cross-sectional view taken along line II-II of FIG. 1.

As shown, the plasma display panel includes a rear substrate 10, an address electrode 11, a rear dielectric layer 12, a partition 13, and a phosphor layer 14. The front substrate 15, the filter 111, the display electrode 16, the front dielectric layer 17, and the protective layer 18 are included.

The back substrate 10 and the front substrate 15 face each other at predetermined intervals. The address electrode 11 extends in the first direction (y-axis direction in the drawing) on the upper surface of the rear substrate 10 and is parallel to each other at a predetermined distance from the neighboring ones. In addition, a back dielectric layer 12 is formed on an upper surface of the back substrate 10, and the back dielectric layer 12 covers the address electrode 11.

The display electrode 16 extends in the second direction (x-axis direction in the drawing) on the lower surface of the front substrate 15 and is parallel to each other at a predetermined distance from the neighboring ones. In addition, the display electrode 16 includes a scan electrode 16b, a sustain electrode 16a, and a bus electrode 16c. The bus electrode 16c is formed on the lower surfaces of the scan electrode 16b and sustain electrode 16a. In addition, the scan electrode 16b and the sustain electrode 16a are spaced apart by a predetermined distance to form a discharge gap.

A front dielectric layer 17 is formed on the bottom surface of the front substrate 15, and the front dielectric layer 17 covers the display electrode 16. The front dielectric layer 17 protects the display electrode 16 from the discharge shape. In addition, wall charges are accumulated to facilitate discharge in the discharge cells 19.

The front dielectric layer 17 is covered with a protective layer 18. The protective layer 18 is a transparent material that not only easily transmits visible light emitted from the phosphor layer 14 but also protects the front dielectric layer 17 from discharge. In addition, the secondary electron emission coefficient is increased to lower the discharge start voltage so that the discharge occurs easily.

A partition 13 is formed between the protective layer 18 and the back dielectric layer 12. The partition 13 includes a horizontal partition member 13a and a vertical partition member 13b.

The horizontal partition member 13a is formed extending in the first direction (y-axis direction in the drawing), and the vertical partition wall member 13b is formed extending in the second direction (x-axis direction in the drawing). In addition, the vertical partition member 13b and the horizontal partition member 13a cross each other. In the present embodiment, the vertical partition wall member 13b and the horizontal partition wall member 13a partition discharge cells 19 in a matrix form.

The discharge cells 19 according to the embodiment of the present invention may be formed in various forms such as a stripe or delta form in addition to the matrix form. The partition wall of this type prevents cross talk between the discharge cells 19 and provides a surface on which the phosphor layer 14 is applied.

The discharge cell 19 is filled with a discharge gas which is an inert gas (for example, a mixed gas of Ne and Xe). Such a discharge gas facilitates the discharge between the sustain electrode 16a and the scan electrode 16b. The discharge generates visible light in the phosphor layer 14, and the visible light is combined to realize an image.

When an image is realized through the front substrate 15, the sustain electrode 16a and the scan electrode 16b are formed of a material such as indium tin oxide (ITO), and the visible light is easily transmitted because the characteristics thereof are transparent. Makes the image easy to implement.

In addition, a filter 111 is formed on the upper surface of the front substrate 15. The filter 111 includes a light guide 111a and an external light reflection preventing member 111b. The light guides 111a extend in the second direction (x-axis direction in the drawing) and are parallel to each other with a predetermined distance from the neighboring ones. In addition, the external light reflection preventing member 111b is formed between the light guides 111a.

In the filter 111, the light guide 111a is provided with the entrance face 20 and the exit face 21. As shown in FIG. The incident surface 20 is a surface on which light formed in the discharge cell 19 is incident, and the emission surface 21 is a surface on which light incident through the incident surface 20 is emitted to the outside.

On the other hand, the area of the exit surface 21 is smaller than the area of the incident surface 20. Due to this structure, the light entering through the entrance surface 20 is focused at the exit surface 21. The focused light has a higher intensity of brightness and a smaller size. Thus, the image becomes more delicate and brighter.

The plasma display panel according to the embodiment of the present invention uses a color subtraction mixing method. Subtractive blending is a method of mixing or superimposing primary colors to create secondary colors.

In particular, in the color redemption table, when the complementary colors are mixed or overlapped, the relation that becomes achromatic (black, gray, etc.) is said to be complementary. Among these achromatic colors, especially black has a property of easily absorbing light.

By subtracting the colors having the above complementary color relationship, the reflective brightness of the panel can be further reduced, and the black ratio and the bright room contrast can be increased.

In the embodiment of the present invention, the partition wall 13 is colored in the first color, the front dielectric layer 17 is colored in the second color, the protective layer 18 is colored in the third color, and the external light reflection preventing member 111b. ) Is colored in the fourth color. In addition, in order to color these, a pigment or a metal element (Cr, Ni, etc.) etc. can be added, and the detailed description about a coloring method is abbreviate | omitted.

In particular, in the embodiment of the present invention, the first color, the second color, the third color, and the fourth color may include cyan, magenta, and yellow, which are three primary colors of the colorant. In this case, the colors of the two components may be colored with the same series of colors. In addition, it is natural that the three primary colors of the colorant may be applied to the four layers in combination in various ways.

In particular, when the colors of the external light reflection preventing member 111b, the front dielectric layer 17, the protective layer 18, and the partition wall 13 overlap, the color is dark. Types of colors and their relationships will be described in detail with reference to FIG. 4.

The plasma display panel including the filter 111 realizes high pixels of an ultra high definition (SHD) level, and contrast can be easily maintained even in bright room conditions. .

In the filter 111, since light is not absorbed at the interface between the light guide 111a and the external light reflection preventing member 111b, the light entering through the incident surface 20 is not easily lost. In addition, the emission surface 21 of the light guide 111a is subjected to a non-glare treatment, thereby reducing the reflected luminance of the plasma display panel.

In the embodiment of the present invention, the light guide 111a and the external light reflection preventing member 111b are formed in the second direction (x-axis direction in the drawing), but in another embodiment, in the first direction (y-axis direction in the drawing). Can also be formed. In addition, in the embodiment of the present invention, the external light reflection preventing member 111b has a stripe shape, but in another embodiment, the external light reflection preventing member 111b may be formed in various shapes such as a lattice shape.

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

Referring to FIG. 3 according to an embodiment of the present invention, 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 discharge cell 19 is partitioned by the partition wall 13. The display electrode 16 extends in the first direction (y-axis direction in the drawing) along the discharge cell 19.

The plasma display panel has an image display area 30 in which an image is displayed. The image display area 30 includes a first area 30a, a second area 30b, and a third area 30c. The first region 30a is a region where the front dielectric layer 17 and the protective layer 18 are visible through the light guide 111a, and the second region 30b is the front dielectric layer 17 through the external light reflection preventing member 111b. ) And the protective layer 18 are visible, and the third region 30c is a region where the front dielectric layer 17, the protective layer 18, and the partition wall 13 are visible through the external light reflection preventing member 111b.

When the external light reflection preventing member 111b is colored cyan, the front dielectric layer 17 is colored magenta, and the partition 13 and the protective layer 18 are colored yellow, they are colored. The overlapping part has a color close to black. Thus, the black ratio and the clear room contrast of the plasma display panel are improved.

On the other hand, conventionally, the external light reflection preventing member 111b is colored in a color close to black that easily absorbs light, and thus has a disadvantage of absorbing visible light formed in the discharge cell 19. However, since the external light reflection preventing member 111 b according to the embodiment of the present invention is colored in a relatively dark color such as cyan, it does not easily absorb visible light formed in the discharge cell 19. For this reason, the luminous efficiency is increased.

In addition, since the partition 13 is also colored with a color that easily reflects visible light like Yellow, there is an effect of increasing the luminous efficiency. Conventionally, in order to increase the black portion and the bright room contrast, the partition wall 13 is colored in a dark color, which causes a problem of lowering the luminous efficiency. In addition, when the partition wall is not colored, a separate black layer is provided on the upper surface of the partition wall 13 to increase the black portion ratio and the bright room contrast. However, in this case there was a problem that a separate process is added.

On the other hand, in order to reduce the halation phenomenon, it is also preferable to color the protective layer 18 as dark (low brightness) color as possible. In addition, in order to further reduce the reflection brightness of the panel, the front substrate 15 may be colored in a dark (low brightness) color as much as possible.

The halation phenomenon is a phenomenon in which visible light formed in the discharge cell 19 is reflected by the protective layer 18, the bus electrode 16c, or the like, so that the visible light reaches another adjacent discharge cell 19, thereby spreading the image. In order to reduce such a halation phenomenon, the protective layer 18 is colored as dark as possible to prevent visible light from being reflected by the adjacent discharge cells 19. Alternatively, a separate black layer may be formed on the lower surface of the bus electrode 16c.

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 properly mixed or overlapped.

Magenta is slightly blueish red (orange), cyan is slightly greenish blue (cyan), and yellow is yellow. Properly mixing or overlaying these three primary inks can produce multiple colors.

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. On the other hand, a color obtained by subtracting and mixing any two colors among the primary colors is called a secondary color.

When any two colors of magenta, yellow and cyan are mixed, the color becomes red, green, and blue. Such red, green, and blue are called secondary colors. In general, these red, green, and blue are called three primary colors of light.

The relationship that overlaps or becomes colored (black, white, gray and so on) is said to be complementary. 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. Magenta, Cyan and Yellow are complementary to each other.

In addition, even if the color is not complementary, the subtractive color of the complementary color has a dark color close to black. This dark color easily absorbs light to increase the black ratio of the plasma display panel, reduce the reflection brightness, and increase the clear room contrast.

In more detail, the color of the external light reflection preventing member 111b is cyan, the color of the front dielectric layer 17 is magenta, and the protective layer 18 and the partition 13 are yellow. ), They are complementary to each other, so they have a dark color close to black or black.

Therefore, it is not necessary to form a separate black layer on the upper surface of the partition 13, thereby simplifying the process. In addition, the partition wall 13 does not have to be colored in a dark color, thereby increasing luminous efficiency. In addition, since the black layer is not required to be formed on the bus electrode 16c, the process is simplified and the luminous efficiency is increased. In addition, since the external light reflection preventing member 111b does not have to be colored in a dark color, the luminous efficiency is increased.

In the embodiment of the present invention, the external light reflection preventing member 111b, the front dielectric layer 17, the protective layer 18, and the partition wall 13 are respectively colored in a specific color, and the specific color is magenta and cyan. ) And Yellow.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications and changes can be made within the scope of the claims and the detailed description of the invention and the accompanying drawings. Naturally, it belongs to the scope of the invention.

As described above, according to the plasma display panel according to the present invention, the external light reflection preventing member, the front dielectric layer, the protective layer, and the partition wall are colored, so that the light emission luminance is high and the black portion and the bright room contrast are improved.

In addition, the partition wall colored with a high brightness like the primary color has the effect of increasing the luminous efficiency.

In addition, the protective layer colored in a dark color among the primary colors has an effect of reducing the halation phenomenon.

Claims (5)

A front substrate disposed to face the rear substrate at intervals; An address electrode formed to extend in a first direction on the rear substrate; Barrier ribs formed in a space between the front substrate and the rear substrate to partition a plurality of discharge cells and colored in a first color; A display electrode formed to extend in a second direction crossing the first direction; A front dielectric layer covering the display electrode and colored in a second color; A protective layer covering the front dielectric layer and colored in a third color; And It includes a filter formed on the outer surface of the front substrate, The filter, A light guide having an entrance surface and an exit surface through which light formed in the discharge cell passes, and an area of the entrance surface larger than that of the exit surface; And An external light reflection preventing member formed adjacent to the light guide and colored in a fourth color; And at least three colors selected from among the first color, the second color, the third color, and the fourth color are subtracted from each other. According to claim 1, And a color in which any two of at least three colors selected from the first color, the second color, the third color, and the fourth color are mixed is complementary to the other color. According to claim 1, The fourth color colored on the protective layer is lower in brightness than the other colors. According to claim 1, And the second color colored on the partition wall is higher in brightness than the other colors. According to claim 1, Each of the at least three colors selected from the first color, the second color, the third color, and the fourth color is magenta, cyan, and yellow-based colors, which are three primary colors of the colorant. Plasma display panel that is one of the different colors selected.

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