JP2004152734A - Plasma display panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize a PDP to suppress noises considered to originate by a gap generated because contact pressure between the front face substrate and the rear face substrate becomes weak in the case an image display is carried out in a low atmospheric-pressure environment such as a place of a high altitude. <P>SOLUTION: By pasting together the front face substrate 2 and the rear face substrate 3 with a sealing member 16 composed of a first sealing member 16a formed in a peripheral part, and a second sealing member 16b which is outside of the first sealing member 16a and thicker than the first sealing member 16a, the parts outside an image display region 15 of the front substrate 2 and/or the rear face substrate 3 are constituted to be deformed elastically. By this, while nearly flatness of the image display region 15 is secured, the contact pressure at a barrier rib 4 by the front face substrate 2 and the rear face substrate 3 exists in the inside of at least either the front face substrate 2 or the rear face substrate 3, and the gap is hardly formed between the front face substrate 2 and the barrier rib 4. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a plasma display panel (hereinafter, referred to as a PDP) known as a large-screen, thin, and lightweight display device.
[0002]
[Prior art]
In recent years, PDPs have attracted attention as display panels (thin display devices) having excellent visibility. This PDP 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. However, from the viewpoint of high definition, a large screen, and easy manufacturing, At present, AC type surface discharge type PDPs have become the mainstream.
[0003]
The structure is such that a front substrate having a plurality of display electrodes including scanning electrodes and sustain electrodes and a back substrate having a plurality of data electrodes orthogonal to the display electrodes are opposed to each other with a partition formed on the back substrate interposed therebetween. Thus, a discharge cell is formed at the intersection of the display electrode and the data electrode, and a phosphor layer is provided in the discharge cell.
[0004]
In addition, a discharge gas is sealed in the discharge cell, and a discharge is generated by a periodic voltage applied between the display electrode and the data electrode, and visible light is emitted by irradiating the phosphor layer with ultraviolet light generated by the discharge. Light is emitted and an image is displayed (for example, see Non-Patent Document 1).
[0005]
[Non-patent document 1]
Hiraki Uchiike and Shigeo Mikoshiba, "All about Plasma Displays", Industrial Research Institute, Inc., May 1, 1997, for example, p79-p80.
[0006]
[Problems to be solved by the invention]
However, in the PDP having the above-described configuration, noise may occur during driving. In addition, there are some PDPs in which noise is not confirmed in a normal environment, but generate noise when used in an environment where the altitude is several thousand meters and the atmospheric pressure is low. Such noise becomes quite annoying when the sound pressure exceeds 30 dB, and significantly lowers the quality as a product.
[0007]
The cause of such noise is considered as follows. The PDP has a structure in which the front substrate and the rear substrate are bonded to each other only with a sealing member formed in a peripheral portion while sandwiching the partition formed on the rear substrate. The contact state between them may be insufficient and a gap may occur. Here, since a periodic voltage is applied to the display electrode and the data electrode of the PDP when the PDP is driven, a periodic attractive and / or repulsive force acts between the front substrate and the rear substrate. It becomes. As a result, when the above gap exists, the front substrate and / or the rear substrate vibrate, which causes noise.
[0008]
Here, as a cause of the above-described gap, the front substrate and the back substrate have a structure in which the front substrate and the rear substrate are bonded only by a sealing member in the peripheral portion. Depending on the flatness of the substrate and / or the rear substrate, the state of contact with the partition walls may be insufficient, or in a region where the outside air pressure is low, for example, at a high altitude, the discharge gas sealed in the PDP may be used. And an attempt to deform the PDP in a direction in which the PDP expands due to pressure.
[0009]
When an amorphous glass material is used for the sealing member, the front substrate and the rear substrate are bonded together and sealed, for example, by heating in a later step such as an exhaust baking step. Gap may occur. This is because the sealing member is re-softened by heating in a later step, and is deformed in a direction in which the distance between the sealing portions between the front substrate and the rear substrate becomes “narrower”. As a result, the front substrate and the rear substrate are deformed. A gap is created when the central part of the substrate and the substrate is deformed in the `` floating '' direction, and when the heating temperature in the subsequent process is near the softening point temperature of the sealing member or higher, there is a problem particularly. Become.
[0010]
The present invention has been made in view of the above problems, and an object of the present invention is to realize a PDP that suppresses noise generated at the time of driving by sufficiently securing a force of pressing a front substrate and a rear substrate with a partition wall. I do.
[0011]
[Means for Solving the Problems]
In order to achieve the above object, a plasma display panel according to the present invention includes a first sealing member formed outside an image display area and a second sealing member formed outside the first sealing member and having a thickness greater than that of the first sealing member. A pair of substrates are bonded together by sandwiching a mounting member therebetween so that at least one of the substrates is elastically deformed at a portion outside the image display area.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
That is, according to the first aspect of the present invention, the first sealing member formed outside the image display area and the second sealing member formed outside the first sealing member and thicker than the first sealing member. A plasma display panel in which a pair of substrates are bonded to each other in a state where at least a portion of one of the substrates outside an image display area is elastically deformed by sealing with members therebetween.
[0013]
According to a second aspect of the present invention, in the first aspect, the first sealing member is made of an amorphous glass material, and the second sealing member is made of a crystalline glass material. Is what you do.
[0014]
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
[0015]
FIG. 1 is a plan view showing a schematic structure of a PDP according to an embodiment of the present invention. FIG. 2 is a sectional perspective view showing a schematic configuration of a part of an image display area of a PDP according to an embodiment of the present invention. FIG. 3 is a cross-sectional view in the X direction in FIG. 2 showing a schematic configuration of the PDP according to one embodiment of the present invention. FIG. 4 is a plan view showing a schematic configuration of a sealing member of the PDP according to one embodiment of the present invention.
[0016]
The PDP 1 has a structure in which a pair of a front substrate 2 and a rear substrate 3 face each other with a partition wall 4 interposed therebetween.
[0017]
The front substrate 2 includes a display electrode 8 composed of N scanning electrodes 6 and N sustaining electrodes 7 formed on one main surface of the front glass substrate 5 (the number is given when the Nth electrode is indicated), The structure has a dielectric layer 9 formed so as to cover the display electrode 8 and a protective layer 10 made of, for example, MgO so as to cover the dielectric layer 9. The scan electrode 6 and the sustain electrode 7 have a structure in which bus electrodes 6b and 7b are stacked on transparent electrodes 6a and 7a.
[0018]
The rear substrate 3 includes M data electrodes 12 formed on one main surface of the rear glass substrate 11 (the number is given when the M-th data electrode is indicated), and a dielectric layer formed so as to cover the data electrodes 12. 13, a partition wall 4 formed at a position corresponding to between the data electrodes 12 on the dielectric layer 13, and phosphor layers 14 R, 14 G, 14 B formed between the partition walls 4.
[0019]
Then, the front substrate 2 and the rear substrate 3 configured as described above are opposed to each other across the partition wall 4 so that the display electrodes 8 and the data electrodes 12 are orthogonal to each other, and the periphery of the front substrate 2 and / or the rear substrate 3 The PDP 1 is formed by bonding together and sealing with a sealing member 16 formed at a predetermined portion of a portion, that is, a portion outside the image display area 15.
[0020]
Here, the sealing member 16 includes a first sealing member 16a and a second sealing member 16b located outside the first sealing member 16a, which is thicker than the partition wall 4 and the first sealing member 16a, that is, higher in height. is there. When the front substrate 2 and the rear substrate 3 are opposed to each other with the first sealing member 16a and the second sealing member 16b having such different thicknesses therebetween, when sealing, initially, FIG. As shown in the figure, the front substrate 2 and the rear substrate 3 are in contact with only the second sealing member 16b. From that state, the front substrate 2 and the rear substrate 3 In order to apply a load F sandwiched between the front substrate 2 and the back substrate 3 so as to improve the adhesion to both the first sealing member 16a and the second sealing member 16b different from each other, FIG. As shown in b), a state in which a portion outside the image display area 15 of the front substrate 2 is bent so as to contact both the first sealing member 16a and the second sealing member 16b, that is, the inside of the PDP 1 is dented. It is in a state of being elastically deformed into an elliptical shape. Then, as shown in FIG. 5 (c), in this state, the first sealing member 16a and the second sealing member 16b are heated to be softened and sealed together, as shown in FIG. 5 (d). Then, a portion outside the image display area 15 of the front substrate 2 is bonded in a state of being elastically deformed into a shape that is concave inside the PDP 1, that is, a shape that is dented inside the PDP 1.
[0021]
In the discharge space 17 formed by the front substrate 2, the rear substrate 3, and the partition 4, for example, a discharge gas of Ne-Xe 5% is sealed at a pressure of 66.5 kPa (500 Torr). The discharge space 17 intersecting with the electrode 12 functions as a discharge cell 18 (unit light emitting region). That is, in the discharge cells 18 to be turned on, discharge is performed by applying a periodic voltage between the display electrode 8 and the data electrode 12 and between the scan electrode 6 and the sustain electrode 7 of the display electrode 8. The fluorescent layers 14R, 14G, and 14B are excited by the ultraviolet rays generated by the discharge to generate visible light. Then, image display is performed by a combination of lighting and non-lighting of the discharge cells 18 of each color.
[0022]
As described above, in the PDP according to one embodiment of the present invention, the sealing member 16 includes the first sealing member 16a and the second sealing member 16b, and is formed of the front substrate 2 and / or the rear substrate 3. The second sealing member 16b is formed in a peripheral portion, that is, at a predetermined position outside the image display area 15, and the thickness, that is, the height of the second sealing member 16b is thicker than the partition wall 4 and the first sealing member 16a. As a result, the portion outside the image display area 15 of at least one of the front substrate 2 and the rear substrate 3 is bonded in a state of being elastically deformed into a shape that is concave inside the PDP 1, that is, a shape that is concave inside the PDP 1. That is.
[0023]
With this configuration, at least one of the front substrate 2 and the rear substrate 3 has a force that causes the front substrate 2 and the rear substrate 3 to be pressed against each other by the partition walls 4. In addition, since the above-described intrinsic force is generated only by the elastic deformation outside the image display region 15, the substantially flatness of the image display region 15 of the PDP 1 can be maintained. . In other words, the front substrate 2 and the rear substrate 3 are maintained while maintaining the features of the PDP 1, such as the fact that the image display area 15 is substantially flat, the transfer of external light and the like is small, and the image distortion is small. Can be strengthened by the partition wall 4.
[0024]
Here, the first sealing member 16a is made of an amorphous glass material, that is, the first sealing member 16a is mainly composed of an amorphous component in the low melting point glass material. It is preferable that the low melting point glass material is made of a crystalline glass material, that is, a low melting point glass material mainly composed of a crystalline material. This is because the crystalline low-melting glass material has the characteristic that crystallization progresses by heating above the softening point, and once it is crystallized, it does not re-soften at the softening point temperature even if it is heated again. After bonding the second sealing member 16b to the rear substrate 3 by, for example, heating in an exhaust baking step or the like, the second sealing member 16b does not soften again. It is possible to suppress the occurrence of the problem that the pressure contact state between the substrate 2 and the back substrate 3 at the partition wall 4 becomes insufficient, and the second sealing member 16b made of a crystalline low melting point glass material In some cases, the interface between crystals may cause a minute leak, but the presence of the first sealing member 16a made of an amorphous low-melting glass material suppresses the occurrence of such a minute leak. To do This is because possible. Here, as the amorphous glass material, for example, PbO.B ₂ O ₃ is used, and as the crystalline glass material, for example, PbO.B ₂ O ₃ .ZnO is used. In each case, a refractory filler such as Al ₂ O ₃ is mixed for adjusting the coefficient of thermal expansion.
[0025]
As described above, in the PDP 1 according to the embodiment of the present invention, at least one of the front substrate 2 and the rear substrate 3 is elastically deformed so that a portion outside the image display area 15 is concave inside the PDP 1. In this manner, the force of pressing the front substrate 2 and the rear substrate 3 at the partition wall 4 independently of the pressure difference between the inside and the outside of the PDP 1 increases the pressure of the front substrate 2 and the rear substrate 3. At least one of them will be inherent. Therefore, even if the pressure difference between the inside and outside of the PDP becomes small, a gap is hardly formed between the front substrate 2 and the partition wall 4, and as a result, it is possible to suppress the generation of noise which is considered to be caused by the gap.
[0026]
In the above description, as shown in FIG. 3, at least one of the front substrate 2 and the rear substrate 3 has a structure in which a force such that the front substrate 2 and the rear substrate 3 are pressed against each other by the partition wall 4 is included. In the above, an example is shown in which a portion outside the image display area 15 of the front substrate 2 is sealed in a state of being elastically deformed into a shape recessed inside the PDP 1, but is not particularly limited to such a configuration. Instead, the thickness of the second sealing member 16b is higher than the height of the partition wall 4 and the thickness of the sealing member 16 configured to be thicker than the thickness of the first sealing member 16a is set to a predetermined value at a peripheral portion, that is, a portion outside the image display area 15. For example, as shown in FIG. 6, a portion outside the image display area 15 of the rear substrate 3 is sealed in a state where it is elastically deformed into a shape that is concave inside the PDP 1, Front substrate as shown in FIG. A similar effect can be obtained even if the portions outside the image display area 15 of both the substrate and the rear substrate 3 are sealed in a state of being elastically deformed into a shape concave inside the PDP 1. Can be. Here, the portion outside the image display area 15 on the rear substrate 3 refers to an area outside the area 15a on the rear substrate 3 corresponding to the image display area 15 on the front substrate 2 as shown in FIGS. Shall point to.
[0027]
In the above description, the shape of the elastic deformation of at least one of the front substrate 2 and the rear substrate 3 outside the image display area 15 is such that the front substrate 2 and the rear substrate 3 are pressed against each other by the partition wall 4. It is not necessary to be limited to the above-described concave shape inside the PDP 1 as long as such force is generated in at least one of the front substrate 2 and the rear substrate 3.
[0028]
FIG. 8 is a perspective view showing a schematic configuration of a plasma display device 50 manufactured using the PDP 1 according to one embodiment of the present invention, in which components are shown in an exploded state. The housing accommodating the PDP 1 includes a front frame 51 and a metal back cover 52, and an opening of the front frame 51 is provided with an optical filter and a front cover 53 made of glass or the like that also protects the PDP 1. ing. The front cover 53 is coated with, for example, silver to suppress unnecessary radiation of electromagnetic waves. Further, the back cover 52 is provided with a plurality of ventilation holes 52a for releasing heat generated in the PDP 1 or the like to the outside.
[0029]
The PDP 1 is held by adhering to the front surface of a chassis member 54 made of aluminum or the like via a heat conductive sheet 55, and a plurality of circuit blocks 56 for driving the PDP 1 for display are provided on the rear surface side of the chassis member 54. Installed. The heat conductive sheet 55 is for efficiently transmitting the heat generated in the PDP 1 to the chassis member 54 to radiate heat. Further, the circuit block 56 includes an electric circuit for performing display driving and control of the PDP 1, and a plurality of electrodes extending beyond the four side edges of the chassis member 54 are provided on the electrode lead portions led to the edges of the PDP 1. Are electrically connected by a flexible wiring board (not shown).
[0030]
A boss portion 54a for attaching a circuit block 56 and fixing the back cover 52 is formed on the rear surface of the chassis member 54 by integral molding using die casting or the like. Note that the chassis member 54 may be configured by fixing a fixing pin to an aluminum flat plate.
[0031]
Since the plasma display device 50 configured as described above uses the PDP 1 according to one embodiment of the present invention, noise is generated even when used in an environment at a high altitude and a low atmospheric pressure. Nothing.
[0032]
Next, in order to verify the effect of the present invention, a PDP is manufactured based on the above-described embodiment, and a result compared with a conventional PDP will be described. The size is 42 "(inch).
[0033]
As the PDP of one embodiment of the present invention, an amorphous low melting point glass material having a softening point of 390 ° C. is used as the first sealing member 16a, and a crystalline low melting point having a softening point of 390 ° C. is used as the second sealing member 16b. A panel using a glass material having a melting point was produced (hereinafter, this PDP is referred to as panel A). As a comparative object, a sealing member made of a conventional amorphous low-melting glass material having a softening point of 390 ° C. was manufactured (hereinafter, this PDP is referred to as a panel B).
[0034]
Sealing was performed by setting the peak temperature at 450 ° C. and holding for 30 minutes. In the subsequent evacuation step, after the inside of the panel was evacuated to about 10 ⁻⁵ Pa, the peak temperature was raised to 370 ° C., and this state was maintained for 6 hours. The discharge gas was filled with Ne (95%)-Xe (5%) at 66.5 kPa (500 Torr).
[0035]
It was confirmed that the panel B produced as described above had a large noise at a high altitude of 2000 m or higher and the PDP was swollen.
[0036]
On the other hand, panel A confirmed that the noise did not increase even at a high altitude of 2000 m or higher, and that the PDP did not expand. From this, it is considered that the pressure contact state between the front substrate and the partition wall is good.
[0037]
The above result indicates that, in panel A, at least one of the front substrate and the rear substrate has a force that causes the front substrate and the rear substrate to be pressed against each other by the partition walls. It is considered that this is because even if the size becomes smaller, a gap is hardly generated between the front substrate and the partition.
[0038]
As described above, in the PDP of the present invention, since at least one of the front substrate 2 and the back substrate 3 is sealed with a portion outside the image display region 15 elastically deformed, the image display region The structure is such that at least one of the front substrate 2 and the rear substrate 3 has a force for pressing the front substrate 2 and the rear substrate 3 against each other with the partition wall 4 while the substantially flatness of 15 is maintained. Therefore, for example, even when the pressure difference between the inside and outside of the PDP becomes small, a gap is hardly generated between the front substrate 2 and the partition wall 4, and as a result, it is possible to suppress the generation of noise considered to be caused by the gap. Becomes possible.
[0039]
Note that the portion outside the image display area 15 in the above description does not strictly refer to all the parts outside the image display area 15, and even if it is only a part of the part outside the image display area 15, This is expressed as a portion outside the image display area 15. For example, the expression “the part outside the image display area 15 is elastically deformed” does not refer only to the case where all the part outside the image display area 15 is elastically deformed. This includes the case where only a part is elastically deformed.
[0040]
【The invention's effect】
As described above, according to the present invention, it is possible to realize a PDP capable of suppressing noise generated at the time of driving while maintaining substantially flatness of an image display area.
[Brief description of the drawings]
FIG. 1 is a plan view showing a schematic structure of a plasma display panel according to one embodiment of the present invention; FIG. 2 is a cross-sectional view showing a schematic configuration of a part of an image display area of the plasma display panel according to one embodiment of the present invention; FIG. 3 is a sectional view showing a schematic configuration of a plasma display panel according to an embodiment of the present invention. FIG. 4 is a plan view showing a configuration of a sealing member in the plasma display panel according to an embodiment of the present invention. FIG. 5 is a diagram schematically illustrating a sealing process in a plasma display panel according to one embodiment of the present invention. FIG. 6 is a cross-sectional view illustrating a schematic configuration of a plasma display panel according to another embodiment of the present invention. 7 is a sectional view showing a schematic configuration of a plasma display panel according to another embodiment of the present invention. FIG. Perspective view showing a schematic configuration of a plasma display device using a that PDP EXPLANATION OF REFERENCE NUMERALS
DESCRIPTION OF SYMBOLS 1 Plasma display panel 2 Front substrate 3 Back substrate 4 Partition wall 5 Front glass substrate 9 Dielectric layer 11 Back glass substrate 13 Dielectric layer 15 Image display area 16 Sealing member 16a First sealing member 16b Second sealing member

Claims (2)

A first sealing member formed outside the image display area, formed outside the first sealing member, and sealed by sandwiching a second sealing member thicker than the first sealing member, thereby forming a pair of substrates. A plasma display panel in which at least a portion of one of the substrates outside the image display area is elastically deformed. The plasma display panel according to claim 1, wherein the first sealing member is made of an amorphous glass material, and the second sealing member is made of a crystalline glass material.

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