JP2003303553A - Plasma display panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a PDP simultaneously establishing both an optical characteristic and an aging characteristic. <P>SOLUTION: In the plasma display panel, one pixel has at least sub pixels of three colors, namely green, red, and blue. At least a sub pixel of one color, of the sub pixels of three colors, has a phosphor film made of different type of phosphor and is formed of two or more discharge cells simultaneously lighting. At least one of two phosphors has at least one property, of the initial luminance larger, the initial color purity higher, and the aging smaller than that of the other phosphor. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a plasma display panel (PDP).

[0002]

2. Description of the Related Art In a PDP, one pixel is usually composed of three color subpixels of green (G), red (R) and blue (B). Therefore, each subpixel of the GBR is composed of one discharge cell provided with a phosphor film made of one kind of phosphor.

[0003]

There are two performances required for a phosphor: optical characteristics such as brightness and chromaticity, and its time-dependent change characteristics. However, at present, there is no phosphor that satisfies these characteristics at the same time. Therefore, the phosphor is selected according to the characteristics of the PDP to be emphasized. This means that one property is excellent, but the other property is sacrificed.

Further, Japanese Patent Laid-Open No. 2000-100332 describes a method of suppressing the deterioration of the blue phosphor with time by making the blue subpixel two discharge cells and alternately lighting them. . Furthermore, JP-A-2000-164
According to Japanese Patent No. 138, two or more grooves are formed by partitioning a subpixel of a certain color with partition walls, and a phosphor film is formed in the grooves to increase the surface area of the phosphor film. A method of increasing brightness is described. Furthermore,
Japanese Patent Laid-Open No. 11-54047 discloses a method of changing the area according to the color. However, none of the methods was able to simultaneously satisfy both the optical characteristics and the time-dependent change characteristics thereof.

[0005]

Thus, according to the present invention, one pixel includes at least three color sub-pixels of green, red and blue, and at least one sub-pixel of the three color sub-pixels is An initial stage of brightness is larger than one of at least two types of phosphors, each of which has two or more discharge cells that are provided with phosphor films made of different types of phosphors and are turned on at the same time. At least one of the properties of high color purity and low deterioration over time.
Provided is a plasma display panel having two characteristics.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The inventors of the present invention first considered mixing a plurality of phosphors in order to achieve both the optical characteristics and the characteristics with time change thereof. However, it is necessary to mix them uniformly. However, it is difficult to emit light uniformly. Therefore, at least one of the sub-pixels of at least one color is configured with two or more discharge cells that respectively include phosphor films made of different types of phosphors and that are simultaneously lit,
The inventors of the present invention have found that the above-mentioned problems can be solved by using phosphors of different types that have different characteristics. Hereinafter, the present invention will be described in detail.

First, according to the present invention, one pixel has three colors of green, red and blue.
It has at least color sub-pixels. Therefore, subpixels of colors other than these three colors may be provided as desired. The sub-pixel may have a striped shape partitioned by stripe-shaped partition walls or a dot-shaped shape partitioned by cross-shaped partition walls. In particular, it is preferable to make the area of the blue sub-pixel larger than that of green and red (for example, double the area).

Further, among the above-mentioned sub-pixels, at least one sub-pixel of one color is composed of two or more discharge cells provided with a phosphor film and being turned on at the same time. Here, the sub-pixel preferably includes two discharge cells in order to further increase the definition. Further, since it is difficult to obtain a blue phosphor having both optical characteristics and aging characteristics thereof, it is preferable that the subpixel to which the present invention is applied includes a blue subpixel. The area of the discharge cell can be appropriately set according to the characteristics of the phosphor used.

Next, two or more discharge cells forming one color sub-pixel are each provided with a phosphor film made of one kind of phosphor, and at least the characteristics different in each color sub-pixel. Two types of phosphors are used. When the number of discharge cells is three or more, each discharge cell may be provided with a phosphor film composed of a number of types of phosphors corresponding to each cell. However, in order to make the manufacturing easier, the discharge cell is
It is preferable to use two or more types of phosphors.

Further, according to the present invention, one of the above-mentioned at least two kinds of phosphors has at least one of the properties that the initial value of luminance is higher, the initial color purity is higher and the deterioration with time is smaller than the other. One of the characteristics is that it has one property. By combining the phosphors in this way, mutual defects can be complemented. For example,
When two kinds of phosphors are used, it is preferable to use phosphors having different characteristics such that the difference in y value of luminance / chromaticity is 20% or less and the difference in change over time is 50% half-time and double or more. As a more specific combination of phosphors, in the case of green, Zn ₂ SiO ₄ : Mn and LaPO ₄ : Ce, Tb, Zn ₂ SiO ₄ : Mn and CeMgAl ₁₁ O ₁₉ : Tb, Zn ₂ SiO ₄ : Mn and BaMg ₂ Al ₁₆ O ₂₇ : Eu, M
n, Zn ₂ SiO ₄ : Mn and BaMgAl ₁₂ O ₁₉ : Mn, Zn ₂ SiO ₄ : Mn and BaMgAl ₁₀ O ₁₇ : Eu, Mn
In the case of red, (Y, Gd) BO ₃ : Eu and Y (P, V) O ₄ : Eu, (Y, Gd) BO ₃ : Eu and (Y, Gd) (P, V)
O ₄ : Eu, (Y, Gd) BO ₃ : Eu and Y ₂ O ₃ : Eu, Y ₂ O ₃ : Eu and Y (P, V) O ₄ : Eu, Y ₂ O ₃ : Eu and (Y, Gd) (P, V) O ₄ : Eu combination, in the case of blue, BaMgAl ₁₀ O ₁₇ : Eu and Y (P, V) O ₄ , BaMgAl ₁₀ O ₁₇ : Eu and (Y, Gd) (P, V) ) O
₄ , BaMgAl ₁₀ O ₁₇ : Eu and BaMg ₂ Al ₁₆ O ₂₇ : E
u, BaMg ₂ Al ₁₆ O ₂₇ : Eu and Y (P, V) O ₄ , BaMg ₂ Al ₁₆ O ₂₇ : Eu and (Y, Gd) (P, V)
An example is a combination of O ₄ . Below, an example of the PDP to which the present invention is applied will be described.

The PDP of FIG. 1 is a three-electrode AC type surface discharge PD.
P. This PDP exemplifies a case where the sub-pixels are formed by stripe-shaped partition walls. In addition,
The present invention is not limited to this type of PDP and can be applied to any configuration. For example, not only AC type D
It may be of C type and may be used for both reflective type and transmissive type PDPs. The PDP 20 shown in FIG. 1 includes a front substrate and a rear substrate.

First, the front substrate is generally a plurality of striped display electrodes formed on a substrate 27, a dielectric layer 24 formed so as to cover the display electrodes, and a dielectric layer 24.
And a protective layer 29 formed thereon and exposed in the discharge space. The substrate 27 is not particularly limited, and examples thereof include a glass substrate, a quartz glass substrate, and a silicon substrate. The display electrode is
It is composed of a transparent electrode 25 such as ITO. Further, a bus electrode (for example, a three-layer structure of Cr / Cu / Cr) 26 may be formed on the transparent electrode 25 in order to reduce the resistance of the display electrode. The dielectric layer 24 is formed of a material normally used for PDPs. Specifically, it can be formed by applying a paste composed of a low melting point glass and a binder on a substrate and firing it. The protective layer 29 is provided to protect the dielectric layer 24 from damage due to collision of ions caused by discharge during display. The protective layer 29 is made of, for example, MgO, CaO, SrO, BaO or the like.

Next, the back substrate is generally a plurality of stripe-shaped address electrodes A formed on the substrate 23,
A dielectric layer 28 covering the address electrodes A, a plurality of stripe-shaped partition walls 21 formed on the dielectric layer 28 between adjacent address electrodes A, and a phosphor film 22 formed including wall surfaces between the partition walls 21. Consists of. In FIG. 1, the phosphor film 22 is composed of red (R), green (G), and blue (B) phosphors, and among these, the blue phosphor is composed of two kinds of B1 and B2. It constitutes a phosphor film. The substrate 23 and the dielectric layer 28 include the substrate 27 and the dielectric layer 24, which form the front substrate.
The same type can be used. The address electrode A is, for example, a metal layer of Al, Cr, Cu, or
It has a three-layer structure of Cu / Cr. The partition wall 21 can be formed by applying a paste made of a low melting point glass and a binder on the dielectric layer 28, firing the paste, and then cutting the paste by a sandblast method. When a photosensitive resin is used as the binder, it can be formed by exposing and developing using a mask having a predetermined shape, and then baking. The phosphor film 22 is a paste in which a particulate phosphor is dispersed in a solution in which a binder is dissolved in a solvent,
It can be formed by applying between the partition walls 21 and baking in an inert atmosphere.

[0014]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto.

Example 1 In this example, a blue phosphor was particularly examined. The blue phosphors are BaMgAl ₁₀ O ₁₇ : Eu (PDB-B manufactured by Nemoto Special Chemical Co., Ltd.) and Y (P, V) O ₄ (P manufactured by Nemoto Special Chemical Co., Ltd.).
DB-A) was used. Note that BaMgAl ₁₀ O ₁₇ : E
The general characteristics of u and Y (P, V) O ₄ are shown in Table 1.

[0016]

[Table 1]

The brightness, chromaticity and aging of the above phosphor were measured. For the measurement, a PDP having the following specifications provided with stripe-shaped sub-pixels was used. In addition, in the measurement, three RGB sub-pixels were defined as one pixel, (Y, Gd) BO ₃ : Eu was used as the red phosphor, and Zn ₂ SiO ₄ : Mn was used as the green phosphor. Screen size: 42 inches Pixel number: 852 x 480 (VGA) Sub pixel number: 2556 x 480 Sub pixel size: 1080 μm x 390 μm Front substrate material: Soda lime glass Front substrate thickness: 3 mm Partition width: 70 μm Partition height: 140 μm Partition pitch: 360 μm Transparent electrode width: 275 μm Bus electrode width: 100 μm Surface discharge gap: 100 μm Shield layer width between transparent electrodes: 350 μm Dielectric layer thickness: 30 μm Protective layer thickness The driving condition was 180 V and 25 kHz.

The results obtained are shown in Table 2 and FIGS.
In addition, FIG. 2 shows the change with time of the brightness of each phosphor.
FIG. 3 shows the change over time of the luminance (Br) / y value of each phosphor, and FIG. 4 shows the change over time of the chromaticity of each phosphor. Since the luminance meter corrects the visibility, when the chromaticity y value increases in the blue region, it shifts to green and shows high luminance. Therefore, the comparison was performed using a value obtained by dividing the luminance (Br) by the chromaticity y value.

[0019]

[Table 2]

As can be seen from Table 2 and FIGS. 2 to 4, BaMgAl ₁₀ O ₁₇ : E which is usually used for the blue phosphor of PDP.
u has a good initial chromaticity, but its luminance, (Br) / y value, and chromaticity change over time are inferior to Y (P, V) O ₄ .

Next, the characteristics of the total blue phosphor film in the case where one pixel is made into four subpixels of RGBB and two kinds of phosphor films made of the above blue phosphor are formed in the subpixels are shown in Table 3 and FIG. ~ 7. 5 shows the time-dependent change in the luminance of the total phosphor, FIG. 6 shows the time-dependent change in the total Br / y value, and FIG. 7 shows the time-dependent change in the chromaticity of the total body.

[0022]

[Table 3]

Compare Tables 2 and 3 and FIGS. 2-4 and 5-7.
Then, the change over time shows that BaMgAl_TenO ₁₇: Better than Eu
That the initial chromaticity is Y (P, V) O_FourBetter
You can see that it is. Therefore, the overall blue phosphor film
Performance can be improved. Also, the blue shown in one pixel
Since the area ratio of is twice as much as green and red,
In contrast, the brightness of blue can be approximately doubled. Furthermore, the color
Degree is BaMgAl_TenO₁₇: Greater than Eu alone, but blue
Since the area ratio is twice that of other colors, the RGB area ratio
It is possible to improve the chromaticity more than when the same.

Example 2 In the same manner as described above, evaluations were made on combinations of green, red and blue phosphors. The results are shown in Table 4. In Table 4, B-1 is a combination of the first embodiment.

[0025]

[Table 4]

In Table 4, ⊚ means that the effect is large, ∘ means that the effect is relatively large, and Δ means that the effect is small. It was confirmed that the same effects as in Example 1 were obtained also with the combinations of the phosphors shown in Table 4.

[0027]

EFFECT OF THE INVENTION At least one sub-pixel among pixels consisting of RGB sub-pixels is composed of two or more discharge cells, and has the same color but different characteristics (luminance, chromaticity or changes thereof with time). By disposing the phosphor film made of a phosphor in the discharge cell, it is possible to improve the drawbacks when one kind of phosphor is used and improve the overall characteristics. For example, in the case of a red phosphor, color purity can be improved, and in the case of a blue phosphor, luminance can be improved and chromaticity change over time can be improved.

[Brief description of drawings]

FIG. 1 is a schematic view of a PDP of the present invention.

FIG. 2 is a diagram showing changes over time in luminance of two types of blue phosphors.

FIG. 3 is a diagram showing changes over time in Br / y values of two types of blue phosphors.

FIG. 4 is a diagram showing chromaticity changes with time of two types of blue phosphors.

FIG. 5 is a diagram showing a change over time in the total luminance of blue phosphors.

FIG. 6 is a view showing a change with time of a total Br / y value of blue phosphors.

FIG. 7 is a diagram showing a change in chromaticity of a blue phosphor as a whole over time.

[Explanation of symbols]

1, 2, 23, 27 substrate 3 electrodes 4,22 Phosphor film 20 PDP 21 partition 24, 28 Dielectric layer 25 Transparent electrode 26 bus electrodes 29 Protective layer A address electrode

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C09K 11/78 CPK C09K 11/78 CPK 11/80 CPM 11/80 CPM 11/81 CPB 11/81 CPB 11 / 83 CQF 11/83 CQF (72) Inventor Teruo Kurai 3-2-1 Sakado, Takatsu-ku, Kawasaki City, Kanagawa Prefecture Fujitsu Hitachi Plasma Display Stock Association (72) Inventor Kiyoshi Suzuki 1-1-15 Kamiogi, Suginami-ku, Tokyo No. 1 Marusan Building Nemoto Special Chemical Co., Ltd. F term (reference) 4H001 CA04 CA05 XA05 XA08 XA12 XA13 XA14 XA15 XA23 XA30 XA39 XA56 XA57 XA58 XA64 YA25 YA58 YA63 YA65 5C040 GG02 GG08 LA02 LA12 MA03 MA10

Claims (3)

[Claims] 1. A pixel has at least three sub-pixels of three colors of green, red, and blue, and among the sub-pixels of three colors, at least one sub-pixel has a phosphor film made of different kinds of phosphors. It is composed of two or more discharge cells that are respectively provided and lighted at the same time, and one of at least two kinds of phosphors has a larger initial value of brightness, a higher initial color purity, and less deterioration over time than the other. Among them, a plasma display panel having at least one property. 2. When the different kinds of phosphors are green, Zn ₂ SiO ₄ : Mn and LaPO ₄ : Ce, Tb, Zn ₂ SiO ₄ : Mn and CeMgAl ₁₁ O ₁₉ : Tb, Zn ₂ SiO ₄ : Mn. And BaMg ₂ Al ₁₆ O ₂₇ : Eu, M
n, Zn ₂ SiO ₄ : Mn and BaMgAl ₁₂ O ₁₉ : Mn, Zn ₂ SiO ₄ : Mn and BaMgAl ₁₀ O ₁₇ : Eu, Mn
In the case of red, (Y, Gd) BO ₃ : Eu and Y (P, V) O ₄ : Eu, (Y, Gd) BO ₃ : Eu and (Y, Gd) (P, V)
O ₄ : Eu, (Y, Gd) BO ₃ : Eu and Y ₂ O ₃ : Eu, Y ₂ O ₃ : Eu and Y (P, V) O ₄ : Eu, Y ₂ O ₃ : Eu and (Y, Gd) (P, V) O ₄ : Eu combination, in the case of blue, BaMgAl ₁₀ O ₁₇ : Eu and Y (P, V) O ₄ , BaMgAl ₁₀ O ₁₇ : Eu and (Y, Gd) (P, V) ) O
₄ , BaMgAl ₁₀ O ₁₇ : Eu and BaMg ₂ Al ₁₆ O ₂₇ : E
u, BaMg ₂ Al ₁₆ O ₂₇ : Eu and Y (P, V) O ₄ , BaMg ₂ Al ₁₆ O ₂₇ : Eu and (Y, Gd) (P, V)
The plasma display panel according to claim 1, wherein the plasma display panel is selected from a combination of O ₄ . 3. The plasma display panel according to claim 1, wherein the blue sub-pixel comprises two discharge cells and has a larger area than the red and green sub-pixels.