KR100570684B1 - Plasma display panel - Google Patents

Abstract

The present invention relates to a plasma display panel, comprising a phosphor layer comprising a red phosphor layer, a green phosphor layer and a blue phosphor layer, wherein the red phosphor layer comprises LiGdF ₄ : Eu.

As described above, the plasma display panel of the present invention uses a red phosphor having excellent luminous efficiency to exhibit excellent luminous efficiency and high luminance.

Red phosphor, lithium gadolium fluoride, PDP

Description

Plasma Display Panel {PLASMA DISPLAY PANEL}

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

2 is a plan view of the plasma display panel shown in FIG. 1;

3 is a perspective view showing the structure of a conventional plasma display panel.

[Industrial use]

The present invention relates to a plasma display panel, and more particularly, to a plasma display panel having excellent red light emission efficiency.

[Prior art]

A plasma display panel is a display device using a plasma phenomenon. When a potential difference is applied between two contacts separated spatially in a gas atmosphere in a non-vacuum state, a discharge is generated, which is called a gas discharge phenomenon. A plasma display panel is a flat panel display element which applied such gas discharge phenomenon to image display.

3 is a perspective view of the plasma display panel 100. As shown in FIG. 3, a plurality of barrier ribs 107 forming discharge cells are disposed between the two substrates constituting the front substrate 103 and the rear substrate 105 at regular intervals. Green and blue phosphor layers 109 are formed. Address electrodes 111 to which address signals are applied are formed on the rear substrate 105, respectively. The front substrate 103 has a plurality of X electrodes 113 and Y electrodes 115 forming a pair of sustain electrodes for one discharge cell at a predetermined interval in a direction crossing the address electrode 111. Is formed. The discharge space is filled with a discharge gas such as Ne-Xe or He-Xe. That is, three electrodes are provided in the discharge space of the plasma display panel, and red, green, and blue phosphors are arranged in a regular pattern in the phosphor layer 109. When a predetermined voltage is applied between the electrodes, plasma discharge occurs. The phosphor layer is excited by ultraviolet rays generated during plasma discharge, and the excited phosphor emits light.

Among the phosphors used in the phosphor layer, red phosphors include (Y, Gd) BO ₃ : Eu, Y (V, P) O ₄ : Eu, (Y, Gd) ₂ O ₃ : Eu or Y ₂ O ₃ : Eu As the luminance of the red phosphor is excellent, no attempt has been made to improve the luminance of the red phosphor until now. However, since the phosphor is excited by one vacuum ultraviolet light and emits one red visible light, the energy of the emitted visible light is lower than that of the incident vacuum ultraviolet light, so that the luminous efficiency is rather low, which leads to the efficiency of the plasma display panel. This may be lowered.

An object of the present invention is to provide a plasma display panel using a red phosphor having excellent luminous efficiency.

In order to achieve the above object, the present invention provides a plasma display panel including a phosphor layer including a red phosphor layer, a green phosphor layer and a blue phosphor layer, wherein the red phosphor layer comprises LiGdF ₄ : Eu. To provide.

Hereinafter, the present invention will be described in more detail.

The present invention relates to a plasma display panel having a red phosphor layer exhibiting excellent luminous efficiency by using crystalline lithium gadolinium fluoride (LiGdF ₄ : Eu) doped with europium ions as a red phosphor for a plasma display panel.

In the red phosphor, when a vacuum ultraviolet photon is irradiated to the phosphor, Gd ³⁺ ions absorb the photon and transfer the energy to Eu ³⁺ in two steps. In each energy transfer step, visible light is emitted by Eu ³⁺ ions, creating two visible photons with a single vacuum ultraviolet photon. This phenomenon is called quantum cutting and the theoretical quantum efficiency is 200%. This is due to the characteristic properties of the excited Gd ³⁺ and Eu ³⁺ ions and the efficient energy transfer between each ion.

Due to this mechanism, lithium gadolinium fluoride phosphors have been previously used to produce (Y, Gd) BO ₃ : Eu, Y (V, P) O ₄ : Eu, where one vacuum ultraviolet photon produces one visible photon. , (Y, Gd) ₂ O ₃ : Eu or Y ₂ O ₃ : Eu Luminous efficiency is very excellent compared to the phosphor. Therefore, when the lithium gadolinium fluoride phosphor is used in the plasma display panel, the luminous efficiency of the red phosphor may be improved by 60% or more and the efficiency of the entire plasma display panel by 15% or more. In addition, lithium gadolinium fluoride phosphors are conventionally used (Y, Gd) BO ₃ : Eu, Y (V, P) O ₄ : Eu, (Y, Gd) ₂ O ₃ : Eu or Y ₂ O ₃ : Eu phosphor Compared with the phosphor, the phosphor is very excellent. Therefore, when the red phosphor of the present invention is applied to the plasma display panel, the red discharge cells can be formed to have a smaller width along the address electrode direction than the green and blue discharge cells, thereby making the discharge characteristics uniform. That is, even when the red discharge cells are formed to be about 10 to 30% smaller than the width lengths of the green and blue discharge cells, appropriate luminance can be matched, and the discharge characteristics can be made uniform.

The plasma display panel including the red phosphor is disposed in a space between the first and second substrates facing each other, the address electrodes formed on the second substrate, and the first substrate and the second substrate to partition the discharge cells. A partition wall, a red fluorescent layer, a green fluorescent layer and a blue fluorescent layer formed in each discharge cell, and discharge holding electrodes formed on the first substrate, wherein the discharge cells are disposed adjacent to discharge cells of different colors; They are separated from the discharge cells of the same color at arbitrary intervals to form a common non-discharge region between the discharge cells, and the red discharge cells are formed smaller in width along the address electrode direction than the green and blue discharge cells.

Each of the discharge cells has a rectangular island shape surrounded by first partition members along the address electrode direction and second partition members intersecting the first partition members, and satisfies the following conditions.

D ₄ (R) <D ₄ (G, (B)

Here, D ₄ (R) represents the width of the red discharge cells along the address electrode direction, and D ₄ (G, B) represents the widths of the green and blue discharge cells along the address electrode direction.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a partially exploded perspective view of a plasma display panel according to an embodiment of the present invention, Figure 2 is a plan view of the plasma display panel shown in FIG.

Referring to the drawings, in the plasma display panel according to the present embodiment, the first substrate 2 and the second substrate 4 are disposed to face each other at arbitrary intervals, and are partitioned by partitions 6 in the space between the two substrates. Discharge cells 8R, 8G and 8B are provided to implement an arbitrary color image with visible light emission by an independent discharge mechanism of each discharge cell 8.

Looking at the configuration thereof, first, the address electrodes 10 are formed on the inner surface of the second substrate 4 in one direction (Y direction in the drawing), and the second substrate 4 is covered with the address electrodes 10. The dielectric layer 12 is formed over the entire inner surface of the substrate. For example, the address electrode 10 is formed in a stripe pattern and formed in parallel with a neighboring address electrode 10 at a predetermined interval.

On the dielectric layer 12 is formed a partition 6, in particular a matrix 6 in the form of a matrix, and red, green, and blue fluorescent layers 14R, 14G across four sides of the partition 6 and the top surface of the dielectric layer 12. 14B). The partition wall 6 consists of the 1st partition wall member 6a according to the address electrode direction, and the 2nd partition wall member 6b along the direction orthogonal to an address electrode (X direction of a figure), and the 1st, 2nd partition member The interior of the discharge cell 8 surrounded by 6a and 6b is filled with discharge gas (Ne-Xe mixed gas).

On the inner surface of the first substrate 2 facing the second substrate 4, a discharge holding electrode 20 made up of the scan electrode 16 and the display electrode 18 is arranged along a direction orthogonal to the address electrode 10. The transparent dielectric layer and the MgO protective film (not shown) are disposed on the entire inner surface of the first substrate 2 while covering the discharge sustaining electrodes 20.

In this embodiment, the discharge sustaining electrode 20 is formed in a stripe pattern, for example, and has a pair of bus electrodes 16a and 18a corresponding to each of the discharge cells 8 and each discharge cell 8 from the bus electrodes 16a and 18a. ) And protruding electrodes 16b and 18b extending inwardly to face each other. The protruding electrodes 16b and 18b may be transparent electrodes such as indium tin oxide (ITO), and it is preferable to use a conventional metal electrode as the bus electrodes 16a and 18a.

As a result, an address voltage Va is applied between the address electrode 10 and the scan electrode 16 to select a discharge cell for emitting light, and a sustain voltage Vs is applied between the scan electrode 16 and the display electrode 18. When applied, the vacuum gas is emitted while the discharge gas in the discharge cell 8 causes plasma discharge, and the vacuum ultraviolet light excites the fluorescent layer 14 and converts it into visible light, thereby enabling color display.

Here, the plasma display panel according to the present embodiment changes the structure of the partition wall 6 partitioning the discharge cells 8 according to the red, green, and blue phosphor characteristics, thereby discharging the red, green, and blue discharge cells 8R and 8G. , 8B) is used to form one pixel, and a structure in which the phosphor efficiency and discharge characteristics of the respective discharge cells 8 are equalized is applied. In this embodiment, the structure consists of applying the volume of the discharge cells 8 differentially by color while minimizing the change of components other than the partition wall 6.

More specifically, as shown in FIG. 2, the first partition member 6a of the first and second partition members 6a and 6b constituting the partition wall 6 covers the entire second substrate 4. It is formed with the same width and partitions the red, green, and blue discharge cells 8R, 8G, and 8B along a direction orthogonal to the address electrode 10. On the other hand, the second partition member 6b is positioned between the discharge cells 8 of the same color arranged along the direction of the address electrode 10 to partition the discharge cells 8, which is the second partition member 6b. The red discharge cell 8R is formed so that its width is smaller than that of the green discharge cell 8G and the blue discharge cell 8B.

That is, the second partition member 6b is formed to satisfy the following condition.

D ₁ (R)> D ₁ (G, B)

Here, D ₁ (R) represents the width of the second partition member positioned between the red discharge cells, and D ₁ (G, B) represents the width of the second partition member located between the green and blue discharge cells. Indicates.

In particular, in the present exemplary embodiment, the plurality of second partition members 6b positioned along the direction orthogonal to the address electrode 10 are formed to have the same horizontal reference line H.

As described above, the plasma display panel according to the present embodiment changes only the width of the second partition member 6b to minimize the volume of the red discharge cells 8R. Therefore, the plasma display panel according to the present exemplary embodiment has the advantage of improving the color temperature characteristics by ensuring the phosphor efficiency and the discharge characteristics of the respective discharge cells 8R, 8G, and 8B, and ensuring the uniformity of discharge.

Hereinafter, preferred examples and comparative examples of the present invention are described. However, the following examples are only preferred embodiments of the present invention and the present invention is not limited to the following examples.

(Example 1)

After mixing the ethyl cellulose binder with the butyl carbitol acetate and terpineol mixed solvent using LiGdF ₄ : Eu as a red phosphor, three roll milling was performed two or more times to prepare a slurry, which is shown in FIG. As described above, when the red discharge cell makes the width ratio of the green and blue discharge cells 100% in the direction of the address electrode, the fluorescent layer is formed by a conventional method in the discharge cell in which the width of the red fluorescent layer is reduced by 20%. A plasma display apparatus was manufactured by drying at a temperature of about 150 degrees for 20 minutes.

(Example 2)

A red phosphor slurry was prepared in the same manner as in Example 1, and when the red discharge cell made the width ratio of the green and blue discharge cells 100% in the address electrode direction as shown in FIG. A fluorescent layer was formed in a discharge cell having a width reduced by 10% by a conventional method, and then dried at a temperature of about 150 degrees for 20 minutes to manufacture a plasma display device.

 (Example 3)

A red phosphor slurry was prepared in the same manner as in Example 1, and when the red discharge cell made the width ratio of the green and blue discharge cells 100% in the address electrode direction as shown in FIG. A fluorescent layer was formed in a discharge cell having a width reduced by 10% by a conventional method, and then dried at a temperature of about 150 degrees for 15 minutes to manufacture a plasma display device.

 (Comparative Example 1)

Using a (Y, Gd) BO ₃ : Eu as a red phosphor, as shown in FIG. 1 in a conventional manner, a red plasma cell was manufactured in which the small discharge cells were smaller than the green and blue discharge cells in the address electrode direction.

The red luminance measured by lighting only the red phosphor layer of the plasma display panel manufactured according to Examples 1 to 3 and Comparative Example 1 and the white luminance measured by lighting all the red, green, and blue phosphors were measured, and the luminous efficiency was measured. The results are shown in Table 1 below. At this time, the power consumption was all equal to 280W.

Red phosphor Red luminance Red relative brightness White brightness White relative brightness Luminous efficiency Comparative Example 1 (Y, Gd) BO ₃ : Eu 398cd / m ² 100% 1312cd / m ² 100% 100% Example 1 LiGdF ₄ : Eu 629 cd / m ² 158% 1521 cd / m ² 116% 116% Example 2 LiGdF ₄ : Eu 673 cd / m ² 169% 1561cd / m ² 119% 119% Example 3 LiGdF ₄ : Eu 645 cd / m ² 162% 1535cd / m ² 117% 117%

As shown in Table 1, it can be seen that the plasma display panels of Examples 1 to 3 are excellent in all of red luminance, white luminance, and luminous efficiency.

As described above, the plasma display panel of the present invention uses a red phosphor having excellent luminous efficiency to exhibit excellent light efficiency and high luminance.

Claims (11)

First and second substrates disposed to face each other; Address electrodes formed on the second substrate; Barrier ribs disposed in a space between the first substrate and the second substrate to partition discharge cells; A red phosphor layer, a green phosphor layer, and a blue phosphor layer including LiGdF ₄ : Eu formed in each discharge cell; And Including discharge sustaining electrodes formed on the first substrate, The partition wall includes first partition wall members positioned along the address electrode direction and second partition wall members intersecting the first partition wall members, And the second partition member is formed such that the red discharge cells are smaller than the green and blue discharge cells. delete The method of claim 1, And the second partition member is disposed between discharge cells of the same color located along the address electrode direction to define the discharge cells. The plasma display panel of claim 1, wherein the partition satisfies the following conditions. D ₁ (R) <D ₁ (G, B) Here, D ₁ (R) represents the width of the second partition member positioned between the red discharge cells, and D ₁ (G, B) represents the width of the second partition member located between the green and blue discharge cells. Indicates. 4. The plasma display panel of claim 3, wherein the second partition members positioned in a direction orthogonal to the address electrode are formed to have the same horizontal reference line. delete delete delete delete delete  The plasma display panel of claim 1, wherein the red discharge cells are formed to be 10 to 30% smaller than the widths of the green and blue discharge cells.

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