JP2004152735A - Plasma display panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize a PDP to suppress noises considered to be caused 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: Because the front face substrate 2 and the rear face substrate 3 of the plasma display panel 1 are made to counter and to be sealed by pinching a first sealing member 16a and a second sealing member 16b formed outside of the first sealing member 16a by a material having a higher softening point temperature than the first sealing member 16a, at least the part outside the image display region 15 of one of the substrate is pasted in elastically deformed state. 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 is made to exist at least on one side of the front face substrate 2 and the rear face substrate 3, and a 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]
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.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, the plasma display panel of the present invention has a first sealing member formed outside the image display area and formed outside the first sealing member, and has a softening point temperature lower than that of the first sealing member. By sealing with a second sealing member made of a high material, a pair of substrates are bonded together in such a manner that at least a portion of one of the substrates outside the image display area is elastically deformed.
[0011]
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 first sealing member are formed outside the first sealing member, and have a higher softening point temperature than the first sealing member. A plasma display panel comprising a pair of substrates bonded to each other by elastically deforming a portion of at least one of the substrates outside the image display region by sealing with a second sealing member made of a material therebetween. .
[0012]
According to a second aspect of the present invention, in the first aspect, the second sealing member is formed to be thicker than the first sealing member.
[0013]
According to a third aspect of the present invention, in the first or second aspect, one of the first sealing member and the second sealing member is made of an amorphous low-melting glass material. That is.
[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 the PDP according to the 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]
The front substrate 2 and the rear substrate 3 configured as described above are opposed to each other with the partition wall 4 interposed therebetween so that the display electrodes 8 and the data electrodes 12 are orthogonal to each other. The PDP 1 is formed by bonding and sealing with a sealing member 16 formed at a predetermined location.
[0020]
Here, the sealing member 16 is composed of a first sealing member 16a and a second sealing member 16b located outside thereof and formed of a material having a higher softening point than the first sealing member 16a. . 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 different softening point temperatures therebetween, when sealing, FIG. As shown in FIG. 3, the front substrate 2 and the rear substrate 3 are so arranged that the adhesion between the front substrate 2 and the rear substrate 3 is improved with respect to the first sealing member 16a and the second sealing member 16b sandwiched therebetween. 3, a heating is performed to melt the sealing member in that state. In the case of an embodiment of the present invention, this heating causes the first sealing member 16a and When both the second sealing members 16b are softened, as shown in FIG. 5 (b), the degree of softening is lower for the second sealing member 16b having a higher softening point temperature than for the first sealing member 16a. If a load that sandwiches the front substrate 2 and the rear substrate 3 is applied in this state, In the part, the difference in the distance between the front substrate 2 and the rear substrate 3 according to the degree of softening of the sealing member, that is, the distance at the first sealing member 16a is located outside the first sealing member 16a. The sealing is performed in a state narrower than the interval at the second sealing member 16b, for example, as shown in FIG. As a result, for example, as shown in FIG. 3, a state in which the portion of the front substrate 2 outside the image display area 15 is elastically deformed and bonded to a shape that is concave inside the PDP 1, that is, a shape that is dented inside the PDP 1. Is obtained.
[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 1 according to the embodiment of the present invention, the sealing member 16 includes the first sealing member 16a and the second sealing member made of a material having a higher softening point temperature than the first sealing member 16a. 16b, and is formed in a peripheral portion of the front substrate 2 and / or the rear substrate 3, that is, at a predetermined position outside the image display area 15, and includes a first sealing member 16a and a second sealing member 16b. The difference in the distance between the front substrate 2 and the rear substrate 3 in the sealing portion due to the difference in the degree of softening due to the difference in the softening point temperature between the first sealing member 16a and the first sealing member 16a. The portion outside the image display area 15 of at least one of the front substrate 2 and the back substrate 3 is sealed by being sealed in a state narrower than the interval at the second sealing member 16b located outside the attaching member 16a. Elastic deformation to form concave inside PDP1 Is that bonded to state that.
[0023]
In the PDP 1 having such a configuration, at least one of the front substrate 2 and the rear substrate 3 has an internal force such that the front substrate 2 and the rear substrate 3 are pressed against each other by the partition walls 4. Further, since the above-described intrinsic force is generated by elastic deformation outside the image display area 15, the substantially flatness of the image display area 15 of the PDP 1 is maintained. In other words, the front substrate 2 and the rear substrate 3 are maintained while maintaining the features inherent in the PDP 1, such that the image display region 15 is substantially flat, the transfer of external light and the like is small, and the image distortion is small. Are strengthened in the pressure contact with the partition wall 4.
[0024]
Here, the difference between the distance between the front substrate 2 and the rear substrate 3 at the first sealing member 16a and the distance at the second sealing member 16b between the front substrate 2 and the rear substrate 3 after the above-described sealing is surely and remarkably. In view of the above, the thickness of the second sealing member 16b is preferably formed in advance to be thicker, that is, higher than the first sealing member 16a.
[0025]
One of the first sealing member 16a and the second sealing member 16b is made of an amorphous low-melting glass material, that is, a material mainly composed of an amorphous low-melting glass material. Is preferred. This is because when a crystalline low-melting glass material is used as a sealing member, the crystalline low-melting glass material is crystallized by heating above the softening point, and once crystallized, it is softened again by heating again. It has the feature that it does not re-soften at the point temperature, but on the other hand, it may have a problem that the interface between the crystals causes micro leak, so such a problem of micro leak does not have a crystal grain boundary. This is intended to be suppressed by a sealing layer made of an amorphous low melting point glass material. 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.
[0026]
As described above, the PDP 1 according to an embodiment of the present invention is formed of the first sealing member 16a and a material having a softening point higher than the first sealing member 16a outside the first sealing member 16a. By sealing the second sealing member 16b with the second sealing member 16b therebetween, a difference in the distance between the front substrate 2 and the rear substrate 3 at the sealing portion due to a difference in the degree of softening, that is, the first sealing At least one of the front substrate 2 and the rear substrate 3 is sealed by the gap between the attachment members 16a being smaller than the gap between the second sealing members 16b located outside the first sealing member 16a. , The portion outside the image display area 15 is elastically deformed into a shape that is concave inside the PDP 1. Therefore, apart from the pressure difference inside and outside the PDP 1, the front substrate 2 and the back substrate 3 Is pressed against the partition wall 4 by the front substrate. , So that the inherent to at least one of the rear substrate 3. 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.
[0027]
In the above description, the first sealing member 16a and the second sealing member 16b formed of a material having a higher softening point than the first sealing member 16a outside the first sealing member 16a are sandwiched. The configuration shown in FIG. 3 shows a state in which a portion outside the image display area 15 of the front substrate 2 is elastically deformed into a shape concave to the inside of the PDP 1 by sealing and facing each other. The present invention is not particularly limited to such a configuration. 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 concave inside the PDP 1. 7, and sealing is performed in a state where the portions outside the image display area 15 of both the front substrate 2 and the rear substrate 3 are elastically deformed into a concave shape inside the PDP 1 as shown in FIG. The same effect can be obtained even if the configuration is made. 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.
[0028]
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.
[0029]
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.
[0030]
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).
[0031]
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.
[0032]
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.
[0033]
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).
[0034]
The PDP according to one embodiment of the present invention includes an amorphous low melting point glass material having a softening point of 390 ° C. as the first sealing member 16a, and an amorphous material having a softening point of 410 ° C. as the second sealing member 16b. A low-melting glass material of high quality was used (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 panel B).
[0035]
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).
[0036]
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.
[0037]
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.
[0038]
According to the above result, in panel A, at least one of the front substrate and the rear substrate has a force in which the front substrate and the rear substrate are pressed against each other by the partition wall, and thus, for example, the pressure difference between the inside and outside of the PDP is reduced. It is considered that even in such a case, a gap is hardly generated between the front substrate and the partition.
[0039]
As described above, the PDP of the present invention includes a first sealing member 16a and a second sealing member formed of a material having a higher softening point than the first sealing member 16a outside the first sealing member 16a. 16b, the front substrate 2 and the back substrate 3 are in a state where a portion outside the image display area 15 is elastically deformed by sealing. The structure is such that at least one of the front substrate and the rear substrate has an internal force for pressing the front substrate 2 and the rear substrate 3 at the partition wall 4 while maintaining substantially flatness. 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.
[0040]
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.
[0041]
【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 (3)

The first sealing member formed outside the image display area and the second sealing member formed outside the first sealing member and made of a material having a higher softening point temperature than the first sealing member are sealed. By doing so, a plasma display panel in which a pair of substrates are bonded together in a state where at least one of the substrates outside the image display area is elastically deformed. The plasma display panel according to claim 1, wherein the second sealing member is formed thicker than the first sealing member. 3. The plasma display panel according to claim 1, wherein one of the first sealing member and the second sealing member is made of an amorphous low-melting glass material.

Images