JP3614247B2 - Plasma display panel - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a plasma display panel (PDP), and is particularly suitable for a high-definition PDP.
[0002]
The surface discharge AC type PDP is attracting attention as a display device for high-vision because it can display colors at high speed and has a long life. In order to expand the use of PDP, it is important to develop a structure suitable for high definition.
[0003]
[Prior art]
A PDP is a self-luminous display panel in which a pair of substrates (usually a glass plate) are arranged to face each other with a minute gap and a discharge space is formed inside by sealing the periphery.
[0004]
The matrix display type PDP has a partition wall with a height of about 100 to 200 μm in the display region. For example, in a surface discharge type PDP for color display, partition walls that are linear in a plan view are provided at equal intervals along the display line direction. The arrangement interval is, for example, about 200 μm in the case of a 21 inch size.
[0005]
The discharge space is partitioned by the barrier ribs, and discharge coupling between cells is prevented. The barrier ribs are also spacers that define the gap size of the discharge space. When the partition is provided only on one substrate, the partition and the component (for example, dielectric layer) on the other substrate are in contact with each other. When the partition is provided on both substrates, the partition on one side and the other side is provided. The two come into contact.
[0006]
Such a partition consists of low melting glass, and is formed in the following procedure.
{Circle around (1)} A glass paste is printed in a predetermined pattern on a substrate. Alternatively, it is printed in a solid film shape and patterned by sandblasting.
[0007]
(2): The glass paste layer having a predetermined thickness (height) obtained in (1) is fired.
[0008]
[Problems to be solved by the invention]
It is desirable that the height of the partition wall be uniform. However, in reality, the upper surface of the partition wall becomes an undulating surface due to non-uniform shrinkage in the firing stage. In particular, the end portion of the partition wall swells larger than other portions. This is because the lower part of the partition wall is in close contact with the support surface and the upper part is drawn toward the center side in plan view. Such a bulge at the end is conspicuous in a partition wall having a linear shape in plan view. When patterning is performed by sandblasting, undercut proceeds at the edge, and the lower part is removed. For this reason, the edge part of a partition warps at the time of baking. Specifically, a portion in the range of several tens of μm near the edge is warped, and the partition wall is locally increased by about 10%. As the cell structure becomes finer, the undercut becomes deeper, the range of warping increases, and the height difference of the partition increases.
[0009]
Conventionally, when the substrates are overlapped with each other, a gap is generated between the upper surface of the barrier rib and the facing surface thereof, so that the partition of the discharge space is insufficient in the portion near the end of the barrier rib in the display area, For this reason, there has been a problem in that the discharge may unnecessarily spread and display may be disturbed. As a technique for solving this problem, a technique of polishing and flattening the upper surface of the partition wall is known. In the case where the width of the partition wall is relatively large, a gap penetrating in the width direction is rarely generated even if it is somewhat missing during polishing. However, if the width of the partition is reduced for high definition, damage to the partition due to polishing cannot be ignored.
[0010]
An object of the present invention is to realize a high-definition display free from disturbance due to discharge coupling between cells.
[0011]
[Means for Solving the Problems]
Of insulator layers such as a dielectric layer that contacts the partition wall and other partition walls, the thickness of the portion facing the end of the partition wall is made smaller than that of the other portion. As a result, the partition walls and the insulating layer are in close contact with each other, and discharge coupling is prevented.
[0012]
In the structure in which the insulator layer covers the electrode, discharge is easily generated by thinning the insulator layer. In the case of the surface discharge type, unnecessary discharge can be prevented by widening the interval between adjacent electrodes. The region where the insulator layer is thin may not be covered with magnesium oxide, which is a high γ material. The latter method is also effective in the case of the counter discharge type.
[0013]
The PDP according to the first aspect of the present invention includes: a first substrate having a partition that extends in and out of a display region; and a second substrate having an insulating layer that extends in a region wider than a region where the partition is formed. And the insulator layer so as to be in contact with each other, and a thickness of a portion of the insulator layer facing an end of the partition wall is set on the inner side of the display region. It is characterized by being smaller than the thickness of the part.
[0014]
In the PDP according to the second aspect of the present invention, the insulator layer is a multilayer structure including a first layer having a uniform thickness and a second layer in which the edge portion has a smaller thickness than the other portions. is there.
In the PDP according to the third aspect of the present invention, the second layer includes a lower layer portion and an upper layer portion having substantially the same shape in plan view and different formation positions.
[0015]
In the PDP according to a fourth aspect of the present invention, an electrode pair extending across the inside and outside of the display area and the insulator layer are sequentially formed on the second substrate. The electrode gap in the portion within the range where the thickness of the insulator layer is small is larger than the electrode gap in the inner portion of the display area.
[0016]
In the PDP of the invention of claim 5, an electrode extending in and out of the display area and the insulator layer are formed in order on the second substrate, and the insulator layer is formed of the insulator layer. The surface layer in a portion excluding the small thickness range is made of magnesium oxide.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a perspective view showing an internal structure of a PDP 1 according to the present invention, and FIG. 2 is a plan view showing an arrangement pattern of partition walls of the PDP 1.
[0018]
The PDP 1 is an AC drive type surface discharge type PDP. A pair of sustain electrodes X and Y are arranged for each line L of the matrix display on the inner surface of the glass substrate 11 on the front side. Each of the sustain electrodes X and Y is composed of a transparent conductive film 41 and a metal film 42 and is covered with an insulator layer 16. The insulator layer 16 includes a dielectric layer 17 for AC driving and magnesium oxide (MgO) 18 deposited on the surface thereof.
[0019]
On the other hand, a base layer 22, an address electrode A, an insulating layer 24, a partition wall 29, and three-color (R, G, B) phosphor layers 28R, 28G, and 28B are provided on the inner surface of the glass substrate 21 on the back side. ing. The planar view shape of each partition wall 29 is macroscopically linear. These partition walls 29 divide the discharge space 30 into sub-pixels in the matrix display line direction, and the gap size of the discharge space 30 is defined to a constant value. One pixel (pixel) of display consists of three subpixels arranged in the line direction. In the PDP 1, since the arrangement pattern of the partition walls 29 is a so-called stripe pattern, the portion corresponding to each column in the discharge space 30 is continuous in the column direction across all the lines L. The emission colors of the subpixels in each column are the same.
[0020]
As shown in FIG. 2, the display area E <b> 1 is an area in a range where the sustain electrodes X and Y and the address electrode A intersect among the inner areas of the frame-shaped sealing material 31 that joins the glass substrates 11 and 21. . A non-light emitting area E2 having a width of several mm is provided between the sealing material 31 and the display area E1. The partition walls 29 are arranged in parallel with the address electrodes A and extend slightly outside the display area E1. That is, in the column direction (extending direction of the partition walls 29), the partition wall formation region E29 in which the partition walls 29 are arranged is wider than the display region E1.
[0021]
FIG. 3 is a cross-sectional view of the main part showing the layer structure of the dielectric layer 17, and FIG.
The dielectric layer 17 includes a first layer 171 made of low-melting glass having a composition in which reaction with the metal film 42 is suppressed, and a second layer 172 made of low-melting glass having a low softening point suitable for surface planarization. It consists of and. In the PDP 1, the second layer 172 includes a lower layer 172A and an upper layer 172B having the same shape (formation area) in plan view. That is, the dielectric layer 17 is composed of a total of three layers. The thicknesses of the respective layers are almost equal to each other and are about 10 μm. Each of these layers can be formed by providing a glass paste on the glass substrate 11 and baking it by a screen printing method or a laminating method.
[0022]
In the column direction, the first layer 171 extends uniformly from the display area E1 to the vicinity of the edge of the glass substrate 11. The second layer 172 also extends to the outside of the partition wall formation region E29. However, the formation positions of the lower layer 172A and the upper layer 172B are shifted from each other in the column direction. For this reason, the thickness of the edge portion in the column direction in the second layer 172 is smaller than the other portions. In the display area E1, the lower layer 172A and the upper layer 172B overlap each other, and the thickness of the second layer 172 is about 20 μm. On the other hand, the thickness of the second layer 172 is about 10 μm at the edge portion. A hatched line in FIG. 4 indicates a thin portion of the second layer 172. This thin portion faces the end 291 of the partition wall 29.
[0023]
Thus, by making the portion of the dielectric layer 17 facing the end portion 291 of the partition wall 29 thinner than the portion in the display region E1, it is possible to prevent discharge coupling. That is, as well shown in FIG. 3, the end portion 291 of the partition wall 29 is locally high (the example shown in the drawing shows an end portion during firing due to undercut when sandblasting is used to form the partition wall. It ’s warped.) If the thickness of the dielectric layer 17 is uniform, a gap is generated between the dielectric layer 17 and the barrier rib 29 in the display region E1, and the partition of the discharge space 30 becomes insufficient. Therefore, by providing a so-called relief corresponding to the local protrusion of the partition wall 29 in the dielectric layer 17, the contact between the dielectric layer 17 and the partition wall 29 can be optimized. Here, the end portion 291 of the partition wall 29 is a portion in the vicinity of the end edge where a remarkable bulge is seen, and its length d is about several tens of μm. Therefore, a length of relief of about 100 μm is sufficient. The surface of the dielectric layer 17 is covered with the MgO film 18, but the MgO 18 is a thin film and is partially broken by contact with the partition wall 29, so that the partition wall 29 and the dielectric layer 17 are substantially directly connected. Abut.
[0024]
As a modified example of the above-described relief formation, there is a form in which the second layer 172 has a single-layer structure and is formed only inside the end portion 291 of the partition wall 29. However, since the composition of the second layer 172 is different from the composition of the first layer 171, the vicinity of the edge of the second layer 172 may rise during firing. If the relief is formed by shifting the lower layer 172A and the upper layer 172B of the same material as in the example of FIGS. 3 and 4, the edge of the portion of the upper layer 172B that overlaps the lower layer 172B is gently formed during firing. As it expands, there is no excitement.
[0025]
The same screen mask can be used to form the lower layer 172A and the upper layer 172B. Further, by providing the second layer 172 in the same or wide range as the partition wall formation region E29, when the second layer 172 has a two-layer structure, the length of the partition wall 29 is minimized and the discharge space during manufacture is reduced. 30 exhausts can be facilitated. If the second layer 172 is narrower than the partition formation region E29, it is necessary to make the partition 29 longer by an amount corresponding to the deviation between the lower layer 172A and the upper layer 172B, and the air permeability of the non-display region E2 is impaired.
[0026]
FIG. 5 is a schematic diagram of the configuration of the PDP 2 according to the second embodiment. 5A is a plan view, FIG. 5B is an enlarged view of a portion b surrounded by a broken line in FIG. 5A, and FIG. 5C is a view taken along the line cc in FIG. 5B. It is sectional drawing. 5, components having the same functions as those of the PDP 1 in FIGS. 1 to 4 are given the same reference numerals regardless of differences in shape and arrangement.
[0027]
PDP 2 is also a surface discharge type. On the inner surface of the glass substrate 11 on the front side, the sustain electrodes X and Y constituting the electrode pair 12, the first layer 171, the lower layer 172A and the upper layer 172B constituting the second layer 172, and the MgO film 18 are sequentially formed. . On the inner surface of the glass substrate 21 on the back side, an address electrode A, a partition wall 29B, and a phosphor layer 28 are sequentially formed.
[0028]
The partition walls 29B are formed in a lattice shape that partitions the display area E1 for each cell. Since the barrier rib pattern is a mesh pattern, the lower layer 172A and the upper layer 172B are shifted from each other in the column direction and the line direction in order to thin the portion of the second layer 172 facing the end 291s of the barrier rib 29s. Each is formed. The diagonal line in FIG. 5A indicates a thin portion of the second layer 172.
[0029]
If the dielectric layer 17 covering the sustain electrodes X and Y is partially thinned, surface discharge is likely to occur in the thin part. Therefore, in the PDP 2, as shown in FIG. 5B, the sustain electrode gap g ′ in the thin region of the dielectric layer 17 inside the sealing material 31 is larger than the size of the surface discharge gap g in the display region E1. It is said that. That is, the wide transparent conductive film 41 is not led out of the range where the lower layer 172A and the upper layer 172B overlap, and the narrow metal film 42 disposed on the side far from the surface discharge gap g of the transparent conductive film 41. Only the leading edge of the glass substrate 11 is led out. In addition, in the PDP 2, the MgO film 18 is provided to avoid the thin region of the dielectric layer 17. The shape of the MgO film 18 can be arbitrarily selected by performing masking during vapor deposition. In the region where the MgO film 18 is not present, the secondary electron emission rate is low and discharge is difficult to occur. It is not necessary to carry out both the setting of the sustain electrode gap g ′ and the setting range of the MgO film 18, and unnecessary discharge can be prevented by only one of them.
[0030]
In the above-described embodiment, the surface discharge type is exemplified, but the present invention can also be applied to a counter discharge type. The dielectric layer 17 is not necessarily composed of a plurality of layers made of different materials. As long as the electrode does not corrode and a predetermined transparency is obtained, it can be composed of a plurality of layers of the same quality, or can be a single layer structure. The component contacting the partition walls 29 and 29s is not limited to the dielectric layer 17, and may be other partition walls, for example. The dimensions, shape, material, formation method, etc. of each component can be selected as appropriate.
[0031]
【The invention's effect】
According to the first to fifth aspects of the invention, it is possible to realize a high-definition display free from disturbance due to discharge coupling between cells.
[0032]
According to the invention of claim 2, the insulator layer facing the end of the partition wall can be easily made thin.
According to the invention of claim 3, it is possible to prevent the generation of voids due to the bulge of the edge portion of the insulator layer.
[0033]
According to invention of Claim 4 and Claim 5, the unnecessary discharge which arises by thinning an insulator layer partially can be prevented.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an internal structure of a PDP according to the present invention.
FIG. 2 is a plan view showing an arrangement pattern of partition walls of a PDP.
FIG. 3 is a cross-sectional view of a principal part showing a layer structure of a dielectric layer.
FIG. 4 is a schematic diagram of a planar view structure of a dielectric layer.
FIG. 5 is a schematic diagram of a configuration of a PDP according to a second embodiment.
[Explanation of symbols]
1, 2 PDP (Plasma Display Panel)
11 Glass substrate (second substrate)
12 Electrode pair 16 Insulator layer 18 Magnesium oxide film (surface layer of a part of the insulator layer)
21 Glass substrate (first substrate)
29, 29s Partition 171 First layer 172 Second layer 172A Lower layer (lower layer part)
172B Upper layer (upper layer part)
291, 291 s Partition end E 1 Display region E 29 Partition formation region (partition formation region)
g Surface discharge gap (electrode gap in the inner part of the display area)
g ′ Sustain electrode gap (electrode gap in the portion where the thickness of the insulator layer is small)
X, Y Sustain electrode (electrode)

Claims (5)

The partition and the insulator layer are in contact with a first substrate having a partition that extends in and out of the display region and a second substrate having an insulator layer that extends over a region wider than the partition formation region. A plasma display panel with a superposed structure,
The plasma display panel, wherein a thickness of a portion of the insulator layer facing an end of the partition wall is smaller than a thickness of a portion inside the display region. The insulator layer is
2. The plasma display panel according to claim 1, wherein the plasma display panel is a multilayer structure including a first layer having a uniform thickness and a second layer having a thickness of an edge portion smaller than that of the other portion. The second layer is
3. The plasma display panel according to claim 2, comprising a lower layer portion and an upper layer portion having substantially the same shape in plan view and different formation positions. On the second substrate, an electrode pair extending over the inside and outside of the display area, and the insulator layer are formed in order,
4. The electrode gap according to claim 1, wherein an electrode gap in a portion of the electrode pair within a range where the thickness of the insulator layer is small is larger than an electrode gap in an inner portion of the display region. Plasma display panel. On the second substrate, an electrode extending in and out of the display area and the insulator layer are formed in order,
The plasma display panel according to any one of claims 1 to 4, wherein a surface layer in a portion of the insulator layer excluding a range having a small thickness is made of magnesium oxide.

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