KR20070104725A - Plasma display panel - Google Patents

Abstract

In the plasma display panel of the present invention, the luminance is improved by the visible light reflected from the bus electrode while applying a complementary color relationship to improve brightness, and between the first substrate, the second substrate, and both substrates disposed to face each other. A partition wall disposed to partition discharge cells, a phosphor layer formed in the discharge cells, an address electrode extending in a first direction corresponding to the discharge cells, and extending in a second direction crossing the first direction, respectively, A first electrode and a second electrode formed on one of the substrates corresponding to the discharge cells, and a dielectric layer covering the first electrode and the second electrode, wherein the dielectric layer is colored in a first color, The barrier rib is colored with a second color having a complementary color relationship with the first color, and each of the first electrode and the second electrode is formed of the discharge cell. Group claim, wherein the bus electrode comprises a bus electrode that are disposed on either side of the first direction includes an inclined surface that is inclined at least with respect to the vertical direction is formed in the vertical end surface of the first substrate and the second substrate.

Description

Plasma Display Panel {PLASMA DISPLAY PANEL}

1 is a perspective view schematically illustrating an exploded view of a plasma display panel according to an exemplary 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 a disposition relationship between discharge cells and electrodes in an embodiment of the present invention.

4 is a detailed cross-sectional view of a state in which visible light is reflected from a bus electrode.

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 in which brightness is reflected by visible light reflected from a bus electrode while improving contrast with a complementary color relationship.

In general, a plasma display panel is a visible light of red (R), green (G) and blue (B) generated by exciting the phosphor using a vacuum ultra-violet (VUV) emitted from the plasma obtained through gas discharge It is a display device for implementing an image.

As an example, an AC plasma display panel forms address electrodes on a back substrate and covers the address electrodes with a dielectric layer. The partition walls are disposed between the address electrodes on the dielectric layer to form a stripe shape, and phosphor layers of red (R), green (G), and blue (B) layers are formed on the partition walls. On the front substrate facing the rear substrate, display electrodes composed of a pair of sustain electrodes and scan electrodes are formed along the direction crossing the address electrodes, and a dielectric layer and an MgO protective film cover the display electrodes. The discharge cell is formed at the point where the pair of address electrodes on the rear substrate and the pair of display electrodes on the front substrate cross each other. In the plasma display panel, millions of unit discharge cells are arranged in a matrix form.

The memory characteristic is used to drive the discharge cells of the plasma display panel. In more detail, in order to generate a discharge between the sustain electrode and the scan electrode constituting the pair of display electrodes, a potential difference of more than a specific voltage is required, and the voltage at this boundary is called a firing voltage (Vf). When the scan voltage and the address voltage are respectively applied to the scan electrode and the address electrode, the discharge is started to form a plasma in the discharge cell, and the electrons and ions of the plasma move toward the electrodes having opposite polarities.

On the other hand, a dielectric layer is applied to each electrode of the plasma display panel, so that most of the moved space charges are stacked on the dielectric layer having opposite polarity, so that the net space potential between the scan electrode and the address electrode is originally applied to the address. The voltage becomes lower than the voltage Va, the discharge is weakened, and the address discharge is extinguished. At this time, a relatively small amount of electrons are accumulated in the sustain electrode, and a relatively large amount of ions are accumulated in the scan electrode, and charges accumulated on the dielectric layer covering the sustain electrode and the scan electrode are wall charges (Qw: Wall). The space voltage formed between the sustain electrode and the scan electrode by these wall charges is called a wall voltage (Vw).

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 higher, sustain discharge occurs in the discharge cell. The vacuum ultraviolet (VUV) generated at this time excites the phosphor and emits visible light through the transparent front substrate.

However, 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, the gas space between the sustain electrode and the scan electrode cannot be discharged.

Various attempts have been made to improve the clear room contrast by increasing the ratio of black, that is, the black portion in the plasma display panel. As an example, a method using a complementary color relationship has been developed.

As described above, the plasma display panel using the complementary color relationship is formed by coloring the dielectric layer of the front substrate by the blue system and by forming the partition wall of the back substrate by the red system, thereby improving the contrast of the bright room.

In addition, the plasma display panel using the complementary color relationship further improves the bright room contrast by coloring the phosphor layer of the back substrate with a red system such as a partition wall.

However, this plasma display panel improves bright room contrast by coloring the phosphor layer in a red system, but has a problem of absorbing a lot of visible light generated in a discharge cell in the phosphor layer of a red system and lowering luminance.

SUMMARY OF THE INVENTION An object of the present invention is to provide a plasma display panel in which luminance is enhanced by visible light reflected from a bus electrode while improving the contrast of a bright room by applying a complementary color relationship.

According to an embodiment of the present invention, a plasma display panel includes a first substrate and a second substrate facing each other, a partition wall disposed between the two substrates to partition discharge cells, a phosphor layer formed in the discharge cells, An address electrode extending in a first direction corresponding to the discharge cells, a first electrode extending in a second direction crossing the first direction and formed on one of the substrates in correspondence with the discharge cells And a second electrode, and a dielectric layer covering the first electrode and the second electrode, wherein the dielectric layer is colored with a first color, and the partition wall is colored with a second color having a mutual complementary relationship with the first color. Each of the first electrode and the second electrode may include a bus electrode disposed in both sides of the first direction of the discharge cell, and the bus electrode may be disposed on the first substrate and the second substrate. It may include an inclined surface formed to be inclined with respect to at least the vertical direction in the vertical direction cross section.

The inclined surface may include a first inclined surface and a second inclined surface formed on both sides of a cross section of the bus electrode.

The first inclined surface and the second inclined surface may have the same length along the inclined direction.

The phosphor layer may include the barrier rib and a first phosphor layer formed on the first substrate partitioned by the barrier rib, and a second phosphor layer formed on the first phosphor layer in the second color.

The first color may be brown and the second color may be blue.

The partition wall extends in the second direction between the first partition members and the first partition members that extend in the first direction and are formed at intervals corresponding to the discharge cells along the second direction. Second barrier rib members may be formed at intervals corresponding to the discharge cells along the first direction.

The first color and the second color overlap at least two layers along a vertical direction of the second substrate.

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 for simplicity of explanation, and like reference numerals designate like elements throughout the specification.

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

Referring to these drawings, the plasma display panel according to the exemplary embodiment is disposed on the first substrate (hereinafter referred to as a "back substrate") 10 and the second substrate which are disposed to face each other at predetermined intervals. (Hereinafter referred to as "front substrate") 20 and partition walls 16 provided between the substrates 10 and 20. The partition wall 16 is formed at a predetermined height between the rear substrate 10 and the front substrate 20 to partition the plurality of discharge cells 17. The discharge cells 17 are filled with a discharge gas (for example, a mixed gas including neon (Ne), xenon (Xe), etc.) so as to generate a vacuum ultraviolet ray by gas discharge, and absorbs the vacuum ultraviolet ray A phosphor layer 19 for emitting visible light is provided.

The plasma display panel includes an address electrode 11 and a first electrode (hereinafter referred to as a “holding electrode”) corresponding to each discharge cell 17 between the rear substrate 10 and the front substrate 20 in order to realize an image by gas discharge. 31 and a second electrode (hereinafter referred to as "scan electrode") 32 are provided.

As an example, the address electrode 11 is formed along the first direction (y-axis direction in the drawing) on the inner surface of the back substrate 10 to form discharge cells 17 adjacent to the y-axis direction. Corresponds continuously. In addition, the plurality of address electrodes 11 are arranged side by side to correspond to adjacent discharge cells 17 in a second direction (the x-axis direction of the drawing) that crosses the y-axis direction.

The address electrodes 11 are covered with a dielectric layer 13 covering the inner surface of the back substrate 10 as described above. The dielectric layer 13 prevents cations or electrons from directly colliding with the address electrode 11 during discharge, thereby preventing damage to the address electrode 11, and also forms and accumulates wall charges. Since the address electrode 11 is disposed on the rear substrate 10 and does not prevent the visible light from being irradiated forward, the address electrode 11 may be formed as an opaque electrode. That is, the address electrode 11 may be formed of a metal electrode having excellent conductance.

The partition 16 is actually provided on the dielectric layer 13 to partition the discharge cells 17. The partition 16 includes first partition members 16a extending in the y-axis direction and second partition members 16b extending in the x-axis direction between the first partition members 16a. In addition, the discharge cells 17 are formed in a matrix structure.

In addition, the partition wall may be formed of first partition wall members extending in the y-axis direction to form discharge cells in a stripe structure (not shown). That is, the discharge cells form a structure that is open along the y-axis direction.

In this embodiment, the partition wall 16 forming the discharge cells 17 in a matrix structure is illustrated. In this state, when the second partition wall members 16b are removed, the partition wall structure is formed by the first partition wall members 16a. Discharge cells are formed. Therefore, a separate illustration of the discharge cells of the stripe structure is omitted here.

The phosphor layer 19 formed in each of the discharge cells 17 is coated with a phosphor face on the side of the partition wall 16 and the surface of the dielectric layer 13 positioned between the partition walls 16 and dried, It is formed by exposure, development, and baking.

The phosphor layer 19 is formed of phosphors of the same color in the discharge cells 17 formed along the y-axis direction. In addition, the phosphor layer 19 is repeatedly formed by the phosphors of red (R), green (G), and blue (B) in the discharge cells 17 repeatedly arranged along the x-axis direction.

Referring to FIG. 3, the sustain electrode 31 and the scan electrode 32 are provided on the inner surface of the front substrate 20 to correspond to each discharge cell 17 to cause gas discharge in the discharge cells 17. To form a surface discharge structure. The sustain electrode 31 and the scan electrode 32 extend in the x-axis direction crossing the address electrode 11.

In addition, the sustain electrode and the scan electrode may be provided between the front substrate and the rear substrate to form an opposite discharge structure corresponding to the discharge cells (not shown).

Each of the sustain electrode 31 and the scan electrode 32 includes transparent electrodes 31a and 32a for generating a discharge and bus electrodes 31b and 32b for applying a voltage signal to the transparent electrodes 31a and 32a, respectively. Is formed. The transparent electrodes 31 a and 32 a are portions which cause surface discharge inside the discharge cell 17 and are formed of a transparent material (for example, indium tin oxide (ITO)) to secure the aperture ratio of the discharge cell 17. The bus electrodes 31b and 32b are formed of a metal material having excellent electrical conductivity to compensate for the high electrical resistance of the transparent electrodes 31a and 32a.

The transparent electrodes 31a and 32a form surface discharge structures with each of the widths W31 and W32 about the center of the discharge cell 17 along the y-axis direction, and form a center portion of each discharge cell 17. Discharge gap G is formed in minutes. The bus electrodes 31b and 32b are disposed on the transparent electrodes 31a and 32a, respectively, and extend in the x-axis direction at the outside of the discharge cell 17. Therefore, when the voltage signal is applied to the bus electrodes 31b and 32b, the voltage signal is applied to each of the transparent electrodes 31a and 32a connected to the bus electrodes 31b and 32b.

Referring back to FIGS. 1 and 2, the sustain electrode 31 and the scan electrode 32 cross the address electrodes 11 and are covered with the dielectric layer 21 facing each other in correspondence with the discharge cells 17. The dielectric layer 21 forms and accumulates wall charges during discharge while protecting the sustain electrode 31 and the scan electrode 32 from gas discharge.

This dielectric layer 21 is covered with a protective film 23. For example, the protective film 23 is formed of transparent MgO to protect the dielectric layer 21, thereby increasing the secondary electron emission coefficient during discharge.

During the plasma display panel driving, a reset discharge is generated by a reset pulse applied to the scan electrode 31 in the reset period, and the scan pulse and the address electrode 11 applied to the scan electrode 32 in the addressing period following the reset period. The address discharge is generated by the address pulse applied to the C1, and then the sustain discharge is generated by the sustain pulse applied to the sustain electrode 31 and the scan electrode 32 in the sustain period.

The sustain electrode 31 and the scan electrode 32 serve as electrodes for applying sustain pulses required for sustain discharge, and the scan electrodes 32 serve as electrodes for applying reset pulses and scan pulses, and the address electrodes. Reference numeral 11 serves as an electrode for applying an address pulse. Since the sustain electrode 32, the scan electrode 32, and the address electrode 11 may have different roles depending on voltage waveforms applied to the sustain electrodes 32, the scan electrodes 32, and the address electrodes 11 are not necessarily limited to these roles.

The plasma display panel selects a discharge cell 17 to be turned on by the address discharge due to the interaction between the address electrode 11 and the scan electrode 32, and the interaction between the sustain electrode 31 and the scan electrode 32. The selected discharge cell 17 is driven by sustain discharge, thereby realizing an image.

On the other hand, the plasma display panel of the present embodiment is formed by coloring the dielectric layer 21 in the first color and the partition wall 16 in the second color in order to improve the bright room contrast by increasing the black ratio using the complementary color relationship.

The first color and the second color overlap black in the vertical direction (z-axis direction) of the front substrate 20.

This first color and the second color have a complementary color relationship that can be represented by black by subtraction mixing. As an example, the first color may be blue and the second color may be brown. That is, the partition 16 is colored brown and the dielectric layer 21 of the front substrate 20 is colored blue.

The plasma display panel to which the complementary color relationship is applied improves bright room contrast while slightly reducing luminance by increasing black ratio. At this time, the blue dielectric layer 21 of the front substrate 20 improves the color temperature.

The blue coloration of the dielectric layer 21 and the brown coloration of the partition wall 16 overlap each other to increase the black portion of the non-discharged area in the plasma display panel.

In addition, in order to increase the black ratio of the discharge region together with the non-discharge region, the phosphor layer 19 is formed of a plurality of layers and includes a colored phosphor layer colored in a second color having a complementary color relationship with the first color.

Referring to FIG. 2, the phosphor layer 19 includes a first phosphor layer 19a formed on the inner surface of the partition wall 16 and the dielectric layer 13 of the back substrate 10 surrounded by the partition wall 16; And a second phosphor layer 19b applied on the first phosphor layer 19a.

The first phosphor layer 19a is formed of a white phosphor to reflect visible light, and the second phosphor layer 19b is colored brown to increase the black portion of the entire plasma display panel together with the partition wall 16. Although the second phosphor layer 19b increases the black portion, it needs to minimize the visible light emitted from the discharge cell 17 to the front substrate 20.

The first phosphor layer 19a has a first thickness T1, and the second phosphor layer 19b has a second thickness T2. This second thickness T2 is smaller than the first thickness T1. That is, the thin second thickness T2 of the second phosphor layer 19b increases the black portion of the portion corresponding to the discharge cell 17 to improve the clear room contrast, and minimizes the absorption of visible light, which is necessarily accompanied by luminance. To maintain.

On the other hand, when the dielectric layer 21 of the front substrate 20 is colored blue, and the partition 16 and the second phosphor layer 19b are colored brown, the bright room contrast is improved by increasing the black fraction. However, the transmittance of visible light irradiated to the front substrate 20 is somewhat reduced. In addition, since absorption of visible light in the partition 16 and the second phosphor layer 19b is increased, the luminance is slightly lowered.

Complementary color relationship using this coloring improves the contrast of a bright room rather than a decrease in luminance due to an increase in the black portion, thereby improving the performance and quality of the plasma display panel as a whole.

Referring to FIG. 4, a structure of a plasma display panel is disclosed in which the external light absorption is further increased in the situation where the luminance is reduced than in the case where the color is not colored due to such coloring to improve the clear room contrast.

In order to compensate for the luminance reduced due to coloration, the bus electrodes 31b and 32b are formed in the vertical direction (z-axis direction) cross section (yz plane) of the back substrate 10 and the front substrate 20 with respect to this vertical direction. It is formed with an inclined surface (131, 132) formed to be inclined.

The inclined surfaces 131 and 132 include first inclined surfaces 131a and 132a and second inclined surfaces 131b and 132b formed at both sides of the end surfaces of the bus electrodes 31b and 32b. In addition, the inclined surfaces 131 and 132 may be formed only on one side of the cross section of the bus electrodes 31b and 32b (not shown).

Since the bus electrodes 31b and 32b are made of an opaque metal material, the bus electrodes 31b and 32b block visible light generated from the discharge cells 17 by the range of the width WB of the bus electrodes 31b and 32b, and the inclined surfaces of the bus electrodes 31b and 32b. 131 and 132 are configured to reflect visible light to be blocked in this width WB range.

The inclined surfaces 131 and 132 are formed on both sides of the bus electrodes 31b and 32b so as to reflect more visible light.

That is, visible light reflected from the inclined surfaces 131 and 132 of the bus electrodes 31b and 32b is irradiated forward through the front substrate 20 to implement an image. There is a need to increase the reflectance of visible light to be blocked in this way.

Therefore, the lengths of the first inclined surfaces 131a and 132a and the second inclined surfaces 131b and 132b which are formed along the inclined direction of the first inclined surfaces 131a and 132a and the second inclined surfaces 131b and 132b are the same. In other words, the bus electrodes 31b and 32b have a cross-sectional structure of an isosceles triangle.

In more detail, the visible light VRs are generated in the discharge cell 17 due to the sustain discharge. For convenience of description, the visible lights VR are defined as first visible light VR1, second visible light VR2, and third visible light VR3 corresponding to each part.

Most of the first visible lights VR1 corresponding to the front substrate 20 of the fraudulent lights VR are irradiated to the front through the front substrate 20 and correspond to the transparent electrodes 31a and 32a. The second visible lights VR2 are irradiated forward through the transparent electrodes 31a and 32a.

The third visible lights VR3 corresponding to the bus electrodes 31b and 32b are reflected on the inclined surfaces 131 and 132 and irradiated forward through the front substrate 20.

At this time, the bus electrodes 31b and 32b including the inclined surfaces 131 and 132 form an isosceles triangular structure so that the first inclined surfaces 131a and 132a and the second inclined surfaces 131b and 132b are formed to have the same length. The light amount of the third visible light VR3 reflected by the first inclined surfaces 131a and 132a and the light amount of the third visible light VR3 reflected through the second inclined surfaces 131b and 132b are the same.

Further, the third visible light VR3 reflected through the first inclined surfaces 131a and 132a formed toward the second partition 16b may have a front substrate (part) corresponding to the second partition 16b forming the non-discharge area. Through 20).

Therefore, the first inclined surfaces 131a and 132a and the second inclined surfaces 131b and 132b reflect the visible light to be blocked by the bus electrodes 31b and 32b to the front substrate 20. As a result, the third visible light VR3 reflected by the first inclined surfaces 131a and 132a and the second inclined surfaces 131b and 132b of the bus electrodes 31b and 32b may improve luminance.

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 dielectric layer of the front substrate is colored in the first color, and the partition wall is colored in the second color, thereby increasing the black ratio of the non-discharged area, thereby improving the bright room contrast. An inclined surface is provided on the bus electrode, which has the effect of improving luminance by reflecting visible light by the inclined surface. In addition, the phosphor layer is formed in two layers, one layer is formed in a small thickness, and the second color is colored to increase the black ratio in the discharge area, thereby improving the clear room contrast while minimizing the absorption of visible light emitted from the front to maintain luminance. It works.

Claims (8)

A first substrate and a second substrate spaced apart from each other; Barrier ribs disposed between the substrates to partition discharge cells; A phosphor layer formed in the discharge cell; An address electrode extending in a first direction corresponding to the discharge cells; First and second electrodes each extending in a second direction crossing the first direction and formed on one of the substrates in correspondence with the discharge cells; And A dielectric layer covering the first electrode and the second electrode, The dielectric layer is colored in a first color, The partition wall is colored with a second color having a complementary color relationship with the first color. Each of the first electrode and the second electrode includes a bus electrode disposed at both sides of the first direction of the discharge cell, And the bus electrode includes an inclined surface that is formed to be inclined with respect to the vertical direction at least in a vertical cross section of the first substrate and the second substrate. According to claim 1, The inclined surface includes a first inclined surface and a second inclined surface formed on both sides of a cross section of the bus electrode. The method of claim 2, And the first inclined surface and the second inclined surface have the same length along the inclined direction. According to claim 1, The phosphor layer, A first phosphor layer formed on the barrier rib and the first substrate partitioned by the barrier rib; And And a second phosphor layer formed on the first phosphor layer in the second color. According to claim 1, And the first color is brown. The method of claim 5, And the second color is blue. The method of claim 6, The partition wall, First partition members extending in the first direction and formed at intervals corresponding to the discharge cells along the second direction; And And second partition members extending in the second direction between the first partition members and formed at intervals corresponding to the discharge cells along the first direction. According to claim 1, And the first color and the second color overlap at least two layers along a vertical direction of the second substrate.

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