JP3909502B2 - Gas discharge display panel - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a gas discharge display panel that performs matrix display by gas discharge such as PDP (plasma display panel), PALC (plasma addressed liquid crystal), and the like, and is arranged along a screen between a pair of electrodes coated with a dielectric in each cell. It is applied to a surface discharge structure that causes discharge.
[0002]
A PDP is a thin device having a pair of substrates as a support, and is excellent in visibility and suitable for large screen display. Therefore, the PDP is used for public displays such as information boards at stations and airports. Also, with the practical use of color screens, it has been widely used in consumer applications such as television images and computer monitors.
[0003]
[Prior art]
As a color display device, a surface discharge AC type PDP has been commercialized. The surface discharge format is a format in which first and second main electrodes that alternately serve as an anode or a cathode are arranged in parallel with one of a pair of substrates in AC driving that maintains a lighting state using wall charges. In the surface discharge type PDP, the phosphor layer for color display is provided on the other substrate facing the substrate on which the main electrode pair is disposed, thereby reducing deterioration of the phosphor layer due to ion bombardment during discharge, Long life can be achieved. Those in which the phosphor layer is disposed on the back side substrate are referred to as “reflection type”, and conversely, those in which the phosphor layer is disposed on the front side substrate are referred to as “transmission type”. What is excellent in luminous efficiency is a reflective type in which the front surface of the phosphor layer emits light.
[0004]
In general, the dielectric layer for AC driving is formed by printing and baking a low-melting glass paste sufficiently thicker (about 20 to 30 times) than the main electrode. The dielectric layer of the conventional PDP is a flat layer having a surface that uniformly covers the inner surface of the substrate including the main electrode pair over the entire screen.
[0005]
[Problems to be solved by the invention]
The above-described cell structure of the surface discharge type is suitable for extending the life, but is an expensive circuit component having a high driving voltage and a large withstand voltage compared to the counter discharge type that generates discharge in the substrate thickness direction perpendicular to the screen. Need. In order to lower the drive voltage, the electric field intensity on the surface of the dielectric layer may be increased, and two methods are conceivable as means for that. One is a method of reducing the arrangement interval (size of the surface discharge gap) of the main electrode pairs, and the other is a method of reducing the thickness of the dielectric layer. However, in the former case, the electric field applied between the main electrodes becomes excessive, and there is a risk of electrode destruction due to electromigration. In the latter case, as the dielectric layer becomes thinner, dielectric breakdown is more likely to occur due to dust contamination or bubble generation during formation. Although this dielectric breakdown problem can be improved to some extent by clean measures and review of manufacturing conditions, it causes a significant increase in cost.
[0006]
On the other hand, in the surface discharge type, it is necessary to provide a partition wall that partitions the discharge space at least in the extension direction of the main electrode to prevent discharge coupling between cells. However, partitioning the discharge space impairs the priming effect between cells, narrows the drive voltage margin, and makes it difficult to exhaust the interior and fill the discharge gas during manufacturing. In particular, when a grid-like (orthogonal type, honeycomb type, etc.) partition wall that partitions the discharge space vertically and horizontally to increase the luminous efficiency by increasing the phosphor coating area, the priming effect between the cells is lost. End up.
[0007]
An object of the present invention is to reduce the driving voltage. Another object is to prevent discharge coupling and secure a moving path of charged particles between cells to facilitate stable driving.
[0008]
[Means for Solving the Problems]
In the present invention, by locally thinning the dielectric layer, the strength of the electric field related to the surface discharge is increased, and a moving path of charged particles is secured as necessary. That is, a dielectric layer having a depression in place is provided. In order to form such a layer, pattern printing of a thick film material or patterning of a solid layer by photolithography may be performed. With either method, a plurality of depressions can be provided simultaneously.
[0009]
In considering the electric field on the surface of the dielectric layer, it is not possible to focus only on the relationship between a pair of electrodes ignoring the influence of adjacent cells. This is because all adjacent electrodes are capacitively coupled, and electric lines of force from one electrode are directed to a pair of electrodes and to another adjacent electrode. Therefore, if the thickness of the dielectric layer between the electrode pairs is made smaller than the thickness between the adjacent electrodes, the electric lines of force in the electrode pairs increase and the electric lines of force to the adjacent electrodes decrease, resulting in surface discharge. The electric field strength of the gap is increased. That is, an electric field strength equivalent to the conventional one can be obtained with a driving voltage lower than that in the case where the conventional thickness is constant. When the portion corresponding to the surface discharge gap in the dielectric layer is depressed and the portion corresponding to between adjacent cells is thickened, the electric field strength is increased.
[0010]
In order to promote the movement of charged particles that contribute to the priming effect, a structure without partition walls that partitions the discharge space is desirable. However, if the partition walls are completely eliminated, the lighting control of the cell having the common electrode cannot be performed. This is because charged particles generated in the lighted cell are attracted to the non-lighted cell and become wall charges, causing erroneous discharge. However, the electric field strength on the surface of the dielectric layer varies depending on the position, and the electric field at the intermediate position between adjacent cells is weaker than the electric field in the surface discharge gap in the cell. Therefore, in the present invention, through-holes between cells are provided by recessing a portion of the dielectric layer that overlaps the partition wall at an intermediate position between adjacent cells, thereby providing a moving path for charged particles. Since the electric field strength is small in this moving path, the discharge coupling is unlikely to occur.
[0011]
In the panel according to the first aspect of the present invention, a plurality of electrodes extending in the row direction of the electrode group corresponding to the matrix screen are arranged on one inner surface of the pair of substrates facing each other with the discharge space interposed therebetween, and the dielectric layer A gas discharge display panel having a surface discharge structure in which a main discharge is generated between the electrodes, and a partition wall for partitioning the discharge space is provided on the other inner surface of the pair of substrates, body layer, wherein are locally thinner than the part the portion covering the electrodes in the electrode gap range of occurrence of the main discharge in each cell constituting the matrix screen, before Symbol partition wall facing life and death to further A plurality of island-shaped depressions for communicating the discharge space between adjacent cells, which are separated from a locally thinned part in the electrode gap range and are recessed with respect to a part covering the electrode Is.
[0015]
3. The gas discharge display panel according to claim 2 , wherein the barrier ribs are formed in an orthogonal grid shape, and the recesses communicate the discharge space between the four cells surrounding the intersection of the barrier rib grids. Is provided.
[0016]
4. The gas discharge display panel according to claim 3 , wherein the electrodes are arranged at equal intervals, the partition walls are formed in a honeycomb lattice shape, and the recesses communicate the discharge space between the cells arranged in a column direction. It is provided to let you. Honeycomb lattices include those having a grid shape other than a hexagon (such as a square).
[0017]
DETAILED DESCRIPTION OF THE INVENTION
1 is a diagram showing an electrode matrix of the PDP 1 of the first embodiment, and FIG. 2 is a perspective view showing a basic structure of the PDP 1 of FIG.
[0018]
In the PDP 1, sustain electrodes X and Y as a pair of first and second main electrodes are arranged in parallel, and in each cell C, the sustain electrodes X and Y intersect with an address electrode A as a third electrode 3. This is a PDP having an electrode surface discharge structure. The sustain electrodes X and Y extend in the row direction (horizontal direction) of the matrix display, and one of the sustain electrodes Y is used as a scan electrode for selecting cells C in units of rows at the time of addressing. The address electrode A extends in the column direction (vertical direction), and is used as a data electrode for selecting the cell C for each column. A region where the sustain electrode group and the address electrode group intersect is a display region in which a plurality of pixels are arranged in a matrix, that is, a matrix screen (screen) SC.
[0019]
As shown in FIG. 2, in the PDP 1, a pair of sustain electrodes X and Y are arranged on the inner surface of the front substrate 11 which is a glass plate for each row L which is a horizontal cell column. Each of the sustain electrodes X and Y is composed of a transparent conductive film 41 and a metal film (bus conductor) 42, and is covered with a dielectric layer 17 made of low-melting glass and having a maximum thickness of about 30 μm. The dielectric layer 17 extends over the entire area of the screen SC, and a protective film 18 made of magnesia (MgO) and having a thickness of several thousand angstroms is provided on the surface thereof. The address electrodes A are arranged on a base layer 22 that covers the inner surface of the back substrate 21 and are covered with a dielectric layer 24 having a thickness of about 10 μm. On the dielectric layer 24, one partition wall 29 having a height of 150 μm in a straight line in plan view is provided between the address electrodes A. These partition walls 29 divide the discharge space 30 into sub-pixels (unit light-emitting regions) in the row direction, and the gap size of the discharge space 30 is defined. Then, phosphor layers 28R, 28G, and 28B of three colors R, G, and B for color display are provided so as to cover the rear side wall surface including the upper side of the address electrode A and the side surface of the partition wall 29. ing.
[0020]
The discharge space 30 is filled with a discharge gas in which xenon is mixed with neon as a main component (filling pressure is 500 Torr), and the phosphor layers 28R, 28G, and 28B are locally excited by ultraviolet rays emitted by xenon during discharge. Emits light. One pixel (pixel) of display is composed of three sub-pixels arranged in the row direction, and the emission colors of the sub-pixels in each column are the same. A structure in each sub-pixel is a cell (display element) C. Since the arrangement pattern of the barrier ribs 29 is a stripe pattern, the portion corresponding to each column in the discharge space 30 extends across all rows L in the column direction. Therefore, the dimension of the electrode gap between adjacent rows L (referred to as reverse slits) is sufficiently larger than the surface discharge gap of each row L (for example, a value in the range of 80 to 140 μm), and the discharge coupling in the column direction is reduced. A value that can be prevented (for example, a value in the range of 400 to 500 μm) is selected.
[0021]
FIG. 3 is a schematic diagram of a main part of the PDP 1 according to the first embodiment.
The dielectric layer 17 is formed with a depression 71 so that a portion in the electrode gap range where surface discharge occurs in each cell C is thinner than a portion covering the sustain electrodes X and Y (portion on the electrode). Yes. The portion facing the partition wall 29 is flat, and the recess 71 is divided for each cell C. Accordingly, no discharge coupling occurs between adjacent cells in the row direction. As described above, the dielectric layer 17 having the same number of depressions 71 as the number of cells is formed by, for example, printing a low melting glass paste in a solid film shape and then overprinting the low melting glass paste on portions other than the depressions. be able to. Alternatively, the dielectric layer formed flat in advance can be formed by a method in which a mask is formed by photolithography and chemically etched.
[0022]
FIG. 4 is a schematic diagram of a main part of the PDP 2 according to the second embodiment. In the figure, components corresponding to the PDP 1 in FIGS. 1 to 3 are denoted by the same reference numerals as in FIGS. 1 to 3 regardless of differences in shape and arrangement. The same applies to the following drawings.
[0023]
In the PDP 2, the planar view shape of the partition walls 29 that divide the discharge space for each column is a belt-shaped meander, and the sustain electrodes X and Y are alternately spaced at regular intervals (surface discharge gaps). It is arranged.
[0024]
That is, each partition wall 29 is undulated at a constant period and amplitude in plan view, and is arranged such that the distance from the adjacent partition wall 29 is periodically smaller than a constant value along the column direction. The constant value is a dimension capable of suppressing discharge, and is determined by discharge conditions such as gas pressure. Since the partition walls 29 are arranged apart from each other in the row direction, the space (column space) between the partition walls 29 is continuous across all the lines 1 on the display screen. Thus, the phosphors can be evenly arranged in the row space using the screen printing method. Here, in the column space, the surface discharge does not occur in the portion with the small width in the line direction, and the wide portion substantially contributes to the light emission. Therefore, cells C are arranged every other column in each row. When attention is paid to two adjacent rows, the columns in which the cells C are arranged are alternately switched for each column. That is, the cells C are arranged in a staggered pattern in both the row direction and the column direction. In PDP2, a total of three cells C of adjacent RGB correspond to one pixel. That is, the arrangement format of the three colors for color display is a triangular (delta) arrangement format. The sustain electrodes X and Y are arranged so that the surface discharge gap corresponds to a wide part in each column space. However, since the sustain electrodes X and Y extend in the row direction across all the column spaces, the surface discharge gap corresponds to a narrow portion in the column space in adjacent columns. Actually, the total number of sustain electrodes X and Y is several hundred (number of lines + 1). Of these sustain electrodes X and Y, those excluding both ends in the arrangement direction correspond to two adjacent rows l. The sustain electrodes X (or Y) at both ends correspond to one row. In one column, surface discharge occurs on one side of the sustain electrodes X and Y, and in the adjacent column, surface discharge occurs on the other side. Since both sides in the column direction of the sustain electrodes X and Y are related to the surface discharge, the metal film (bus conductor) 42 is overlapped on the central portion of the transparent conductive film 41 in the column direction.
[0025]
Also in such a PDP 2, the dielectric layer 17 covering the sustain electrodes X and Y has a portion (surface on the electrode) where the portion within the electrode gap range where the surface discharge occurs in each cell C covers the sustain electrodes X and Y. The depression 71 is formed so as to be thinner than the portion.
[0026]
FIG. 5 is a schematic diagram of a main part of the PDP 3 according to the third embodiment.
In the PDP 3, the arrangement pattern of the barrier ribs 29 is a stripe pattern that partitions the discharge space for each column similar to the PDP 1 in FIG. 3. The sustain electrodes X and Y are alternately extended to one end side and the other end side in the column direction alternately for each column along the row direction, and the surface is formed between the extended portion and the adjacent extended portion of the sustain electrode. Patterning is performed so that electric discharge occurs. As in the PDP 2 described above, among the hundreds of sustain electrodes X and Y, those excluding both ends in the arrangement direction correspond to two adjacent rows l, and one sustain electrode X (or Y) at both ends is one. Corresponds to a line. Since the overhang direction is changed for each column, the cells C are arranged in a staggered pattern in both the row direction and the column direction.
[0027]
In the dielectric layer 17 covering the sustain electrodes X and Y, the partition walls 29 are arranged so that the portion in the electrode gap range where the surface discharge occurs in each cell C is thinner than the portion covering the sustain electrodes X and Y. A recess 71 longer than the interval is formed. These depressions 71 have a role of increasing the electric field of the surface discharge gap and a role of a moving path of charged particles contributing to the priming effect in the cell C adjacent in the row direction. Since the cells C are shifted in the column direction between adjacent columns, no discharge coupling occurs between the cells C.
[0028]
FIG. 6 is a schematic diagram of a main part of the PDP 4 according to the fourth embodiment.
The electrode structure and partition structure of the PDP 4 are the same as those of the PDP 1 in FIG. In the PDP 4, the dielectric layer 17 has a bulge 75 so that a portion within the range of the sustain electrode arrangement gap between the cells C adjacent in the column direction is locally thicker than a portion covering the sustain electrodes X and Y locally. Is provided. These ridges 75 increase the electric field contributing to the surface discharge together with the depressions 71 of the surface discharge gap.
[0029]
FIG. 7 is a schematic diagram of a main part of a PDP 5 according to the fifth embodiment.
Also in the PDP 5, a pair of sustain electrodes X and Y are arranged for each row as in the PDP 1 in FIG. 3, and the partition walls 29 are arranged in stripes. The dielectric layer 17 that covers the sustain electrodes X and Y is provided with a recess 71 that serves as a moving path of the charged particles, together with a recess 71 for facilitating the surface discharge D1. One recess 78 is provided at a portion of the reverse slit that faces the partition wall 29 and is divided from each other in the row direction.
[0030]
FIG. 8 is a schematic diagram of a main part of the PDP 6 according to the sixth embodiment.
In the PDP 6, the discharge space 30 is partitioned for each cell C by orthogonal lattice-shaped partition walls 29. The dielectric layer 17 is provided with depressions 71 for facilitating the occurrence of the surface discharge D1 in the portions corresponding to the surface discharge gaps in the individual cells C, and surrounding the lattice points in the portions corresponding to the lattice points of the partition walls 29. A recess 78 is provided to allow the discharge spaces of the cells C to communicate with each other.
[0031]
FIG. 9 is a perspective view showing the partition structure of the PDP 7 according to the seventh embodiment, and FIG. 10 is a schematic view of the main part of the PDP 7 according to the seventh embodiment. In FIG. 10A, the metal film 42 is omitted.
[0032]
In the PDP 7, the discharge space is partitioned for each cell C by the honeycomb lattice-shaped partition walls 29. The dielectric layer 17 is provided with depressions 71 for facilitating surface discharge at portions corresponding to the surface discharge gaps in the individual cells C, and 2 adjacent to the portion corresponding to the lattice points of the partition walls 29 in the column direction. A recess 78 is provided to allow the discharge spaces of the cells C to communicate with each other.
[0033]
【The invention's effect】
According to the first to third aspects of the invention, since the electric field related to the surface discharge is increased, the driving voltage can be reduced. In addition, it is possible to facilitate the movement of charged particles that contribute to the priming effect between cells and to stabilize the display while preventing the coupling of discharge.
[0035]
According to the invention of claim 2 or claim 3 , even when the partition wall surrounding the cell is formed for high brightness and high luminous efficiency, it is possible to secure an internal air passage necessary for manufacturing, The priming effect between cells can be used for driving.
[Brief description of the drawings]
FIG. 1 is a diagram showing an electrode matrix of a PDP 1 according to a first embodiment.
2 is a perspective view showing a basic structure of the PDP in FIG. 1. FIG.
FIG. 3 is a schematic diagram of a main part of the PDP according to the first embodiment.
FIG. 4 is a schematic diagram of a main part of a PDP according to a second embodiment.
FIG. 5 is a schematic diagram of a main part of a PDP according to a third embodiment.
FIG. 6 is a schematic diagram of a main part of a PDP according to a fourth embodiment.
FIG. 7 is a schematic diagram of a main part of a PDP according to a fifth embodiment.
FIG. 8 is a schematic diagram of a main part of a PDP according to a sixth embodiment.
FIG. 9 is a perspective view showing a partition structure of a PDP 7 according to a seventh embodiment.
FIG. 10 is a schematic diagram of a main part of a PDP 7 according to a seventh embodiment.
[Explanation of symbols]
1-7 PDP (Gas Discharge Display Panel)
11 Front side substrate 17 Dielectric layer 29 Bulkhead 30 Discharge space 71 Depression (thin portion of dielectric layer)
75 Raised 78 SC screen with depressions (matrix screen)
X, Y sustain electrodes (electrodes extending in the row direction)

Claims (3)

A plurality of electrodes extending in the row direction of the electrode group corresponding to the matrix screen are arranged on one inner surface of the pair of substrates facing each other with the discharge space interposed therebetween, and are covered with a dielectric layer, so that the main discharge is performed. A gas discharge display panel having a surface discharge structure generated between the electrodes,
A partition wall for partitioning the discharge space is provided on the other inner surface of the pair of substrates,
Said dielectric layer, said portion of the electrode gap range of occurrence of the main discharge in each cell constituting the matrix screen than the portion covering the electrode are locally thinner, before Symbol partition wall and facing the further And a plurality of island-like depressions for communicating the discharge space between adjacent cells, which are recessed with respect to a portion covering the electrode and separated from a locally thinned portion in the electrode gap range. Gas discharge display panel characterized by having The partition walls are formed in an orthogonal lattice shape,
The gas discharge display panel according to claim 1, wherein each of the depressions is provided so as to communicate the discharge space between the four cells surrounding the intersection of the barrier rib lattice. The electrodes are arranged at equal intervals,
The partition walls are formed in a honeycomb lattice shape,
The gas discharge display panel according to claim 1, wherein each of the recesses is provided so as to communicate the discharge space between the cells arranged in a column direction.

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