JP2003317629A - Plasma display panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a plasma display panel with a smaller characteristics difference of initialization discharge in each discharge cell for red color, green color and blue color. <P>SOLUTION: Two substrates of a front face substrate 1 and a back face substrate 6 are placed in opposition, between which, discharge cells 11r, 11g, and 11b having each a phosphor layer 10r, 10g, and 10b emitting light of red, green and blue color are formed, with a thickness 12g of the green-color phosphor layer 10g made smaller than that 12r of the red-color phosphor layer 10r and that 12b of the blue-color phosphor layer 10b. <P>COPYRIGHT: (C)2004,JPO

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a large screen,
The present invention relates to a plasma display panel known as a lightweight display device. 2. Description of the Related Art In recent years, a plasma display panel has attracted attention as a thin display device having excellent visibility, and higher definition and a larger screen are being promoted. [0003] The plasma display panel is roughly classified into an AC type and a DC type in terms of driving, and there are two types of discharge types, a surface discharge type and a counter discharge type. Due to the simplicity of the above, an AC type surface discharge type plasma display panel has become the mainstream at present. FIG. 2 is a perspective view showing a main part of a typical plasma display panel. The structure and operation will be described below. A plurality of scan electrodes 2 and sustain electrodes 3 are formed in pairs on a front substrate 1, and a transparent dielectric layer 4 is formed on these electrodes. Further, a protective layer 5 made of magnesium oxide is formed on the dielectric layer 4, and its thickness is considerably smaller than the thickness of the dielectric layer 4. The dielectric layer 4 has a current limiting function peculiar to the AC type plasma display panel, and is a factor that can make the life longer than that of the DC type. A plurality of address electrodes 7 are formed on a rear substrate 6 disposed opposite to the front substrate 1 so as to be orthogonal to the scanning electrodes 2 and the sustain electrodes 3. An underlying layer covers the address electrodes 7. 8 are formed. A partition 9 is provided on the base layer 8 between the address electrodes 7, and a phosphor layer 10 emitting red, green or blue light is provided on the base layer 8 between the partition 9.
Are sequentially formed. A plurality of discharge cells 11 are formed between the front substrate 1 and the rear substrate 6 that are opposed to each other, a red phosphor layer 10r is provided on the red discharge cell 11r, and a green phosphor cell 11g is provided on the green discharge cell 11g. Is provided in the blue discharge cell 11b.
0b is provided. The discharge cell 11 is filled with a mixed gas of neon (Ne) and xenon (Xe) as a discharge gas at a pressure of about 66.5 kPa (500 Torr). FIG. 3 shows an example of a standard driving waveform of a plasma display panel. As shown in FIG. 3, the drive waveform includes four operation periods: an initialization period, a write period, a sustain period, and an erase period. In the initializing period, an initializing discharge for forming initializing charges (a predetermined amount of wall charges required during a writing operation) and generating priming particles is performed between the scan electrode 2 and the address electrode 7. In the discharge cell where sustain discharge is to be performed in the sustain period, write discharge is selectively performed between scan electrode 2 and address electrode 7 and between scan electrode 2 and sustain electrode 3.
In the sustain period, a sustain discharge is performed between the scan electrode 2 and the sustain electrode 3 in a discharge cell to which a write discharge has been selectively performed in the write period. In the erasing period, erasing discharge of wall charges generated by the sustain discharge is performed between the scan electrode 2 and the sustain electrode 3. Therefore, in order to reliably perform the writing discharge, the sustaining discharge, and the erasing discharge after the initializing period, an appropriate amount of the initializing charge required for these series of discharges is formed between the scan electrode 2 and the address electrode 7. It is important to perform an initializing discharge. By the way, the initializing discharge during the initializing period is generated between the scanning electrode 2 and the address electrode 7, that is, the underlayer 8 and the phosphor layer 10 on the back substrate 6 side.
This is performed in the discharge space via the dielectric layer 4 and the protective layer 5 on the front substrate 1 side, and the red, green and blue phosphor layers 10
Due to the difference in the phosphor material used for each of r, 10g, and 10b, a difference in voltage and current characteristics occurs in the setup discharge in the discharge space where the phosphor layers of each color are formed. For example, (Y ₂ Gd) BO ₃ as a red phosphor material:
Using Eu, Zn ₂ SiO ₄ as a green phosphor material:
Mn was used, and BaMgAl ₁₀ was used as a blue phosphor material.
When O ₁₇ : Eu is used, especially green discharge cells 11 g
The discharge starting voltage of the initializing discharge tends to be higher than the discharge starting voltages of the red discharge cell 11r and the blue discharge cell 11b. Also, regarding the discharge current in the initializing discharge, the discharge cells 11r and 1r in the green discharge cell 11g.
1b, the green discharge cell 11g is less likely to perform a sufficient initializing discharge than the discharge cells 11r and 11b, and tends to adversely affect the writing characteristics after the initializing period. The present invention has been made to solve such a problem, and an object of the present invention is to provide a plasma display panel in which a difference in characteristics of an initializing discharge in each of red, green, and blue discharge cells is smaller. And In order to achieve the above object, a plasma display panel according to the present invention comprises two substrates arranged opposite to each other, and red, green and blue phosphor layers between the substrates. Each is formed by forming a discharge cell,
The thickness of the green phosphor layer is smaller than the thickness of the red phosphor layer and the thickness of the blue phosphor layer. With this configuration, it is possible to reduce the difference in discharge characteristics between the discharge cells having the red, green, and blue phosphor layers, respectively. An embodiment of the present invention will be described below with reference to the drawings. The same parts as those shown in FIG. 2 are given the same numbers. FIG. 1 is a sectional view showing a main part of a plasma display panel according to an embodiment of the present invention. This plasma display panel is configured by disposing two substrates facing each other and forming a discharge cell having phosphor layers that emit red, green, and blue light between the substrates. That is, a plurality of scan electrodes 2 and sustain electrodes 3 are arranged in pairs on the front substrate 1 as in the plasma display panel shown in FIG. A dielectric layer 4 is formed so as to cover, and a protective layer 5 is formed on the dielectric layer 4. Also,
A plurality of address electrodes 7 are arranged on the back substrate 6, and a base layer 8 is formed so as to cover the address electrodes 7. A partition 9 is formed between the address electrodes 7 on the base layer 8 in parallel to the address electrodes 7, and a phosphor layer 10 r emitting red, green or blue light is provided in a space partitioned by the partition 9. 10g and 10b are provided. The front substrate 1 and the back substrate 6 are connected to the scanning electrodes 2
The sustain electrode 3 and the address electrode 7 are arranged so as to be orthogonal to each other, and the periphery thereof is hermetically sealed. In the discharge space between the front substrate 1 and the rear substrate 6, a discharge gas containing a mixture of Ne and Xe is used. Is filled at a predetermined pressure and a predetermined mixing ratio. Discharge cells 11 having phosphor layers of respective colors are formed at intersections between the scan electrodes 2 and the sustain electrodes 3 and the address electrodes 7.
That is, the red discharge cells 11r are connected to the red phosphor layers 10r.
r, and the green discharge cell 11g has the green phosphor layer 10
g, and the blue discharge cell 11b is
b. Then, a sustain discharge is generated in each discharge cell 11 by using the above-described conventional driving method, and the phosphor layer 10 is formed.
The image is displayed by emitting light. In the plasma display panel of the present embodiment, the thickness of the green phosphor layer 10g is smaller than the thickness of the red phosphor layer 10r and the thickness of the blue phosphor layer 10b. Here, the thickness of the phosphor layer 10 of each color is determined by measuring the thickness of the phosphor layer 10 when measured from the bottom surface of the phosphor layer 10, that is, the surface of the underlayer 8 with which the phosphor layer 10 is in contact.
Is the thickness. As shown in FIG. 1, the phosphor layer 10 is formed so as to be thinner at the center of the discharge cell 11 and thicker at the partition 9 side. In this case, the thicknesses 12r and 12g of the red, green and blue phosphor layers are provided. , 12b are values at the portion where the thickness from the bottom surface of the phosphor layer 10 of each color is the thinnest. In addition,
The thickness 12 of the phosphor layer can be adjusted by the viscosity of the phosphor material applied when forming the phosphor layer 10, the amount of application, the content of the resin, and the like. Next, the thickness 12r of the red phosphor layer 10r
And the thickness 12b of the blue phosphor layer 10b is 30 μm,
Table 1 shows the results of examining the discharge starting voltage of the setup discharge for the plasma display panel in which the thickness of the green phosphor layer 10g was changed from 12 g to 5 μm to 30 μm. Note that (Y ₂ Gd) BO ₃ : Eu is used as a red phosphor material, Zn ₂ SiO ₄ : Mn is used as a green phosphor material, and BaMgAl ₁₀ O ₁₇ : E is used as a blue phosphor material.
u was used. [Table 1] As shown in Table 1, 10 g of the green phosphor layer
In the conventional panel having a thickness of 12 g of 30 μm, the discharge starting voltage in the red, green and blue discharge cells is 218.
V, 233 V, and 216 V, and the discharge start voltage of the green discharge cell is higher than the discharge start voltages of the other discharge cells, and a maximum difference of 17 V occurs. On the other hand, by reducing the thickness 12g of the green phosphor layer 10g, the discharge starting voltage in the green discharge cell 11g is reduced, and by reducing the thickness 12g of the green phosphor layer 10g to 15 to 20 μm. The discharge start voltage is 214 to 220 V, and the difference between the discharge start voltage of the red and blue discharge cells can be kept within 4 V, and the difference of the discharge start voltage between the discharge cells is smaller than that of the conventional panel. can do. The green phosphor layer 10g has a thickness of 12g.
It can be confirmed from the waveform of the discharge current that the discharge current of the initialization discharge in each of the red, green, and blue discharge cells when is set to 15 to 20 μm is more uniform than in the conventional panel. As described above, the thickness 12g of the green phosphor layer 10g is appropriately set to a value smaller than the thickness 12r of the red phosphor layer 10r and the thickness 12b of the blue phosphor layer 10b. This can reduce the difference in voltage and current characteristics of the setup discharge between the discharge cells of each color. It is considered that this is because the effective cell voltage applied to the discharge space becomes more uniform in the discharge cells of each color. Thereby, the characteristic difference between the write discharge and the sustain discharge can be reduced, and a plasma display panel having a larger drive margin can be realized. As is clear from the above description, according to the plasma display panel of the present invention, it is possible to reduce the difference in the characteristics of the voltage and current of the initializing discharge in the discharge cells of each color, A plasma display panel with a larger margin can be realized.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view showing a main part of a plasma display panel according to an embodiment of the present invention. FIG. 2 is a perspective view showing a main part of a conventional plasma display panel. Waveform diagram showing the method of driving the plasma display panel of the present invention.

Claims (1)

Claims: 1. A discharge cell having two substrates disposed opposite to each other and having red, green, and blue phosphor layers between the substrates, respectively, wherein a green phosphor layer is formed. A plasma display panel having a thickness smaller than a thickness of a red phosphor layer and a thickness of a blue phosphor layer.