KR100573157B1 - Plasma display panel - Google Patents

Abstract

According to the present invention, a plasma display panel is disclosed. The plasma display panel includes an upper substrate and a lower substrate disposed to face each other, a partition wall disposed between the upper substrate and the lower substrate to define a plurality of discharge cells together with the upper substrate and the lower substrate, and discharges continuously arranged in one direction, respectively. A plurality of discharge sustaining electrodes disposed opposite to each other, having a terminal electrode extending over the cells, and a plurality of protruding electrodes connected to the terminal electrode and extending inwardly of each discharge cell, and arranged in pairs with each other, continuous in different directions Address electrodes arranged to intersect with the discharge sustaining electrodes over the discharge cells arranged, upper dielectric layers and lower dielectric layers covering the discharge sustaining electrodes and the address electrodes, respectively, phosphor layers disposed in the discharge cells, and discharge cells. And a discharge gas enclosed therein, wherein the protruding electrode includes at least one electrode portion extending in one direction and an electrode portion. Comprises a connecting portion interconnecting the electrodes, the connection portion is spaced a predetermined distance from the line of symmetry passing through the center of the discharge cell parallel to the connection. According to the disclosed plasma display panel, the manufacturing process is simplified and a high level of luminance of light can be obtained.

Description

Plasma Display Panel {Plasma display panel}

1 is an exploded perspective view showing a conventional plasma display panel;

2 is an exploded perspective view showing a plasma display panel according to a first embodiment of the present invention;

3 is a plan view showing an electrode structure of the plasma display panel shown in FIG.

4 is a profile of light emission luminance according to the ratio of the separation distance to the discharge cell width,

5 is a cross-sectional view taken along the line VV of FIG. 2;

6 is a plan view showing an electrode structure of a plasma display panel according to a second embodiment of the present invention;

<Description of Symbols for Major Parts of Drawings>

111: upper substrate 114: upper dielectric layer

115: protective layer 121: lower substrate

122: address electrode 123: lower dielectric layer

124,224 bulkhead 125 phosphor layer

130: common electrode 140: scanning electrode

131, 141, 231, 241: first electrode 132, 142, 232, 242: second electrode

133,143,233,243: third electrode portion 134,144: terminal electrode

234,244: fourth electrode portion 138,148,238,248: connection portion

160,260: discharge cell

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display panel for realizing an image using gas discharge. More particularly, the present invention relates to a plasma display panel having an improved structure capable of simplifying a manufacturing process and obtaining a high level of luminance.

Recently, a device employing a plasma display panel as a flat panel display device has a large screen and has excellent characteristics of high definition, ultra-thin, light weight, and wide viewing angle, and is easier to manufacture than other flat panel display devices. It is attracting attention as a large flat panel display device.

1 shows a conventional plasma display panel. In general, the plasma display panel includes an upper panel 10 and a lower panel 20 bonded to the upper panel 10. Discharge sustaining electrode pairs 50 are disposed on the lower surface of the upper substrate 11, and the upper dielectric layer 14 filling them and the protective layer 15 covering the upper dielectric layer 14 are sequentially formed. Here, one electrode of the discharge sustaining electrode pair 50 becomes the common electrode 30, and the other electrode becomes the scan electrode 40.

On the other hand, an upper surface of the lower substrate 21 is formed with an address electrode 22 extending to intersect with the discharge sustaining electrode pair 50 and a lower dielectric layer 23 embedded therein. A partition wall 24 is formed on the lower dielectric layer 23 to partition the plurality of discharge cells 60. The phosphor layer 25 is formed on the lower dielectric layer 23 surrounded by the partition wall 24 over the side surface of the partition wall 24.

Each of the common electrode 30 and the scan electrode 40 includes transparent electrodes 30a and 40a and bus electrodes 30b and 40b. The transparent electrodes 30a and 40a are formed of a transparent material that is a conductor capable of causing a discharge and does not prevent light emitted from the phosphor layer 25 from advancing to the upper substrate 11. tin oxide) film. However, the ITO film is difficult to be formed by a simple process such as screen printing due to the material property, and there is a problem in that a special patterning technique such as sputtering, which requires expensive equipment and processes, is required.

In addition, in order to improve the electrical conductivity of the transparent electrodes 30a and 40a, bus electrodes 30b and 40b made of a conductive metal material should be formed at the outer end thereof, so that a separate alignment process is required, as well as on the ITO film. When the bus electrodes 30b and 40b are formed on the substrate, there are problems such as compatibility and adhesion depending on the electrode material, and since the ITO film is transparent, it is difficult to align with the bus electrodes 30b and 40b. In addition to the problems in the manufacturing process, the light transmittance of the transparent electrode is about 80% to about 20% light loss occurs, the light efficiency of the plasma display panel is also reduced. In order to solve the above-mentioned problems, a plasma display panel in which discharge sustaining electrode pairs are composed of only bus electrodes has been developed. However, opaque bus electrodes have a problem in that light transmittance of visible light is lowered, thereby degrading luminance and luminous efficiency.

An object of the present invention is to provide a plasma display panel having an improved structure in which the manufacturing process is simplified and the manufacturing cost is reduced in order to solve the above and other problems.

Another object of the present invention is to provide a plasma display panel which achieves the above-described object and improves luminous luminance and luminous efficiency.

In order to achieve the above objects and other objects, the plasma display panel of the present invention,

An upper substrate and a lower substrate disposed to face each other;

A partition wall disposed between the upper substrate and the lower substrate to define a plurality of discharge cells together with the upper substrate and the lower substrate;

A plurality of terminal electrodes extending across the discharge cells continuously arranged in one direction, and a plurality of protruding electrodes connected to the terminal electrodes extending inwardly of each discharge cell, and arranged to be paired with each other; Discharge sustaining electrodes;

Address electrodes arranged to intersect the discharge sustain electrodes over discharge cells continuously arranged in different directions;

An upper dielectric layer and a lower dielectric layer covering the discharge sustain electrodes and the address electrodes, respectively;

A phosphor layer disposed in the discharge cells; And

And a discharge gas encapsulated in the discharge cells.

The protruding electrode,

At least one electrode unit extending in one direction; And

It includes a plurality of connecting portions for connecting the electrode portion and the terminal electrode,

The connecting portions are spaced a predetermined distance from the symmetry line passing through the center of each discharge cell parallel to the connecting portions.

Plasma display panel according to another aspect of the present invention,

An upper substrate and a lower substrate disposed to face each other;

A partition wall disposed between the upper substrate and the lower substrate to define a plurality of discharge cells together with the upper substrate and the lower substrate;

At least two electrode portions each extending over the discharge cells continuously arranged in one direction and spaced apart from each other, and a plurality of connecting portions interconnecting the electrode portions, and a plurality of oppositely arranged pairs; Discharge sustaining electrodes;

Address electrodes arranged to intersect the discharge sustain electrodes over discharge cells continuously arranged in different directions;

An upper dielectric layer and a lower dielectric layer covering the discharge sustain electrodes and the address electrodes, respectively;

A phosphor layer disposed in the discharge cells; And

And a discharge gas encapsulated in the discharge cells.

The connecting portions are spaced a predetermined distance from the symmetry line passing through the center of each discharge cell parallel to the connecting portions.

In the present invention, when the distance from the center line of the connection portion to the symmetry line is called the separation distance of the connection portion, the ratio of the separation distance to the discharge cell width is preferably 0.017 to 0.31.

Next, a plasma display panel according to an exemplary embodiment of the present invention will be described in detail with reference to the accompanying drawings.

2 shows a plasma display panel according to a first embodiment of the present invention. The plasma display panel includes an upper panel 110 and a lower panel 120 that is bonded to the upper panel 110. The upper panel 110 includes an upper substrate 111, a plurality of discharge sustaining electrode pairs 150 formed in a predetermined pattern under the upper substrate 111, and an upper dielectric layer filling the discharge sustaining electrode pairs 150. And a protective layer 115 covering the upper dielectric layer 114.

The upper substrate 111 is generally formed of a transparent material based on glass. The discharge sustain electrode pair 150 extends in one direction (x direction), and includes a common electrode 130 and a scan electrode 140 that face each other and form a pair. Each of the common electrode 130 and the scan electrode 140 has terminal electrodes 134 and 144 extending in one direction (x direction), and have a predetermined length in the terminal electrodes 134 and 144 and the inside of each discharge cell 160. The grid-shaped protruding electrodes 135 and 145 extend.

The terminal electrodes 134 and 144 are connected to circuit portions (not shown) to receive driving power. The applied driving power is distributed to the protruding electrodes 135 and 145 formed along the longitudinal direction (x direction). The terminal electrodes 134 and 144 are preferably formed of a metal material having high electrical conductivity. For example, the terminal electrodes 134 and 144 may be formed of Ag, Au, Al, Cu, Cr, or a laminate thereof. Meanwhile, the protruding electrodes 135 and 145 may also be integrally formed with the same metal material as the terminal electrodes 134 and 144. The terminal electrode is preferably formed to have a sufficient width (t4, see FIG. 3) to prevent smooth communication of the driving power and resistance loss in the longitudinal direction. For example, the terminal electrode may be formed to about 80 μm.

Referring to FIG. 3, each of the protruding electrodes 135 and 145 connected to the terminal electrodes 134 and 144 may be spaced apart from each other in parallel with the first electrode parts 131 and 141, the second electrode parts 132 and 142, and the third electrode parts 133 and 143. And a plurality of connection parts 138 and 148 interconnecting the electrode parts and the terminal electrodes 134 and 144. The separation distances d1 and d2 between the electrode parts arranged in parallel to each other may be set by specific design conditions. For example, in order to increase the opening ratio at the center portion of the discharge cell 160 where the discharge and the light emission are concentrated, the separation distance d1 between the first electrode portions 131 and 141 and the second electrode portions 132 and 142 may be set wide. In order to promote the diffusion of discharge between the second electrodes 132 and 142 and the third electrodes 133 and 143, the separation distance d2 between them may be set relatively narrow.

An approximately rectangular gap region S is formed in the protruding electrodes 135 and 145. The gap region S increases the light transmittance to increase the light emission luminance, and decreases the electrode formation area to reduce the discharge current. Meanwhile, the electrode structure of the protruding electrode is not limited to that shown in FIG. 3, and may be variously modified. When a predetermined AC voltage sufficient to generate a discharge is applied between the discharge sustaining electrode pairs 150, an initial discharge (discharge gap, g) is formed between the first electrode portions 131 and 141 facing each other at the innermost side of the discharge cell 160. ) Is discharged to the adjacent second electrode portions 132 and 132 and the third electrode portions 133 and 143.

When the line widths t1 of the first electrode parts 131 and 141 are increased, discharge stability is improved, but light transmittance is decreased and discharge current is increased. When the line width t1 decreases, it has the opposite advantages and disadvantages. Therefore, in order to ensure stable discharge and opening ratio, the line width t1 is preferably about 60 µm to 80 µm. For the same reason, it is preferable that the line widths t2 and t3 of the second electrode portions 132 and 142 and the third electrode portions 133 and 143 are also set to about 60 μm to 80 μm so as to enable stable discharge diffusion while ensuring a sufficient aperture ratio.

On the other hand, the connection parts 138 and 148 interconnect the electrodes, thereby inducing the initial discharge started from the first electrode parts 131 and 141 to the second electrode parts 132 and 142 and the third electrode parts 133 and 143. That is, when a predetermined AC voltage sufficient to cause a discharge is applied between the discharge sustaining electrode pairs 150, the discharge starts in the form of a short gap (discharge gap g) between the first electrode portions 131 and 141, and the discharge is performed. The diffusion is diffused into the second electrode portions 132 and 142 and the third electrode portions 133 and 143 along the connecting portions 138 and 148, and transitions to long gap discharges as the discharge distance increases. In the long gap discharge, as many discharge gases are excited as the discharge distance increases, more phosphor layers are emitted, thereby obtaining a high level of luminance.

The second connection parts 138b and 148b of the connection parts 138 and 148 are disposed on both left and right sides of the discharge cell 160, and the first connection parts 138a and 148a are disposed between the second connection parts 138b and 148b. When the connecting portions 138 and 148 are disposed across the center portion of the discharge cell 160, the light transmittance at the center portion of the discharge cell 160 where the discharge and the light emission are concentrated is lowered. Therefore, the connection parts 138 and 148 are preferably spaced apart from the center of the discharge cell 160 by a predetermined interval. The first connection part (mainly, rather than the second connection parts 138b and 148b which are disposed on both left and right sides of the discharge cell 160). The placement of 138a, 148a is problematic.

The first connecting portions 138a and 148a of the present invention shown in FIG. 3 are spaced apart from the symmetry line L-L passing through the center of the discharge cell 160 in parallel with the connecting portion by a predetermined distance e. This separation distance e may be set based on the experimental data shown in FIG. 4.

In this experiment, the emission luminance was measured while changing the ratio (e / w) of the separation distance e to the width w of the discharge cell. Here, the width (w) of the discharge cell, as shown in Figure 3, means the distance between the partition wall 124 defining one discharge cell 160, the separation distance of the connecting portion (e) the width of the discharge cell Since it is reasonable to change according to (w), it is preferable that the design criterion for the separation distance e is set to a relative ratio with respect to the discharge cell width w. The emission luminance was measured while changing the ratio (e / w) of the separation distance from 0 to 0.31. For reference, the width (w) of the discharge cell was fixed at 290 μm, and the separation distance (e) was changed from 0 μm to 90 μm. I was.

As can be seen in Figure 4, even if the ratio (e / w) of the separation distance increases from 0 to 0.017 there is no change in the light emission luminance. This is the result that the separation distance e is not sufficiently increased to affect the luminance of light emitted. However, when the ratio (e / w) of the separation distance increases from 0.017 to 0.31, the light emission luminance continuously rises from 800 cd / m ² to reach 870 cd / m ² . This is because, as the separation distance e increases, the light transmittance at the center portion of the discharge cell 160 where a relatively large amount of visible light is emitted is improved. Based on the experimental results shown in FIG. 4, the separation distance ratio (e / w) of the connection unit is preferably set to 0.017 to 0.31. Here, when the ratio e / w of the separation distance exceeds the upper limit value (e / w = 0.31, e = 90), the first connection parts 138a and 148a are excessively disposed at the edge of the discharge cell 160, Discharge diffusion along the first connectors 138a and 148a may become unstable. That is, when the first connecting portions 138a and 148a are disposed at the edges of the discharge cells 160 having relatively weak discharge strength, the discharge diffusion function may be weakened. The ratio of the separation distance (e / w) is within 0.31 It is desirable to be limited.

Referring to FIG. 3, the line width t5 of the connecting portions 138 and 148 is preferably limited to a predetermined range for light transmittance. For example, the line width t5 of the connecting portions 138 and 148 may be 40 μm to 60 μm. It can be set to. In addition to the discharge diffusion function, the connection parts 138 and 148 receive a driving power from the terminal electrodes 134 and 144 and distribute the same to the electrodes constituting the protruding electrodes 135 and 145. On the other hand, although not shown in the drawings, the light absorbing layer may be formed on the upper side of the discharge sustaining electrode pair 150, the light absorbing layer is formed so as to have a dark (light) of 50% or more light absorption. In this case, the emotional quality may be improved without forming a separate black stripe for absorbing external light.

Referring back to FIG. 2, an upper dielectric layer 114 is formed below the upper substrate 111 to cover the discharge sustaining electrode pair 150. The upper dielectric layer 114 prevents cations or electrons from colliding with the discharge sustaining electrode pair 150 and damages the discharge sustaining electrode pair 150, and induces charge to help accumulate wall charges. The protective layer 115 is not an essential component, but is preferably formed. The protective layer 115 prevents cations and electrons from colliding with the upper dielectric layer 114 during the discharge to damage the upper dielectric layer 114. In other words, it emits a lot of secondary electrons.

The lower panel 120 includes a lower substrate 121, a plurality of address electrodes 122 formed in a predetermined pattern on the lower substrate 121, and a lower dielectric layer 123 filling the address electrodes 122. And a partition wall 124 formed on the lower dielectric layer 123 and partitioning the plurality of discharge cells 160, and a phosphor layer 125 disposed inside the discharge cells 160.

The lower substrate 121 serves to support the address electrodes 122, the lower dielectric layer 123, and the like, and is typically formed of glass as a main material. The address electrodes 122 are used to cause an address discharge, and more specifically, serve to lower a voltage for sustain discharge. The address electrode 122 is formed to cross the discharge sustaining electrode pair 150, and may be formed in a stripe pattern along one direction (y direction). The lower dielectric layer 123 serves to prevent the positive electrode or the electrons from colliding with the address electrode 122 when the discharge is damaged.

As shown in FIG. 2, the partition wall 124 may be formed in a matrix pattern extending in the x and y directions. The partition wall 124 divides the discharge space between the upper substrate 111 and the lower substrate 121 into a plurality of discharge cells 160, thereby providing optical and electrical crosstalk between the discharge cells 160. -talk). The phosphor layer 125 is formed on the lower dielectric layer 123 surrounded by the partition wall 124 over the side surface of the partition wall 124. Herein, the discharge cells 160 refer to subpixels constituting one pixel, and each of the discharge cells 160 corresponds to a red light emitting subpixel, a green light emitting subpixel, and a blue light emitting light according to the type of the phosphor layer 125 disposed. Subpixels are distinguished. The phosphor layer 125 receives vacuum ultraviolet rays emitted from the plasma generated by the discharge and converts the ultraviolet rays into visible rays. Although not shown in the drawing, discharge cells such as Ne, Xe, and the like and a mixed gas thereof are filled in the discharge cells 160.

FIG. 5 is a cross-sectional view of the plasma display panel taken along the line VV of FIG. 2. For convenience of description, the lower panel 120 is shown rotated 90 degrees with the A-A line as a boundary. In the plasma display panel of the present invention configured as described above, by applying an address voltage between the address electrode 122 and the scan electrode 140, an address discharge occurs and a discharge cell in which sustain discharge occurs as a result of the address discharge ( 160) is selected. Thereafter, when a predetermined AC voltage is applied between the common electrode 130 and the scan electrode 140 of the selected discharge cell 160, the sustain discharge occurs between the common electrode 130 and the scan electrode 140. Here, the discharge is started between the first electrode portions 131 and 141 (P1), and the second electrode portions 132 and 142, the third electrode portions 133 and 143, and the terminal electrodes 134 and 144 are adjacent to the connection portions 138 and 148, respectively. The discharge paths are diffused (P2, P3, P4). Ultraviolet rays are emitted while the energy level of the discharge gas excited by the sustain discharges P1 to P4 is lowered. The ultraviolet rays excite the phosphor layer 125 applied in the discharge cell 160. As the energy level of the excited phosphor layer 125 is lowered, visible light is emitted, and the emitted visible light constitutes an image.

6 shows an electrode structure of a plasma display panel according to a second embodiment of the present invention. The plasma display panel of this embodiment has substantially the same components having the same functions and effects except for the matters described below with the plasma display panels shown in FIGS. 2 and 3. Also in this embodiment, the discharge sustaining electrode pair 250 includes a common electrode 230 and a scan electrode 240, and each of the common electrode 230 and the scan electrode 240 has a predetermined interval d1 and d2. The electrode parts are arranged in parallel with each other. In more detail, the first electrode parts 231 and 241 are disposed with the discharge gap g interposed therebetween, and the second electrode parts 232 and 242 are sequentially disposed from the first electrode parts 231 and 241 toward the edge of the discharge cell 260. , Third electrode portions 233 and 243, and fourth electrode portions 234 and 244 are disposed. Here, the electrode parts are formed in a stripe shape along one direction (x direction). In addition, the electrode parts are connected to each other by the connecting parts 238 and 248, and the second connecting parts 238b and 248b are formed at both left and right sides of the discharge cell 260, and the first connecting parts 238a and 248a are connected to the second connecting parts. It is formed between 238b and 248b.

In the present embodiment, the electrodes constituting the discharge sustaining electrode pair 250 are not divided in units of discharge cells, but are formed over the discharge cells 260 in a row. Accordingly, a voltage drop that may occur in the longitudinal direction (x direction) of the discharge sustaining electrode pair 250 may be prevented, and a uniform electric field may be formed in all the discharge cells 260. Meanwhile, the matters related to the partition wall 224 are substantially the same as those described in the first embodiment, and reference may be made to them.

According to the plasma display panel of the present invention, the following effects can be achieved.

First, the discharge sustaining electrode of the present invention does not include a transparent electrode and is formed of a single layer structure made of a metal material, and therefore, expensive manufacturing equipment is not required, and workability of patterning is improved. In particular, since the discharge sustaining electrode of the present invention is formed in a single layer structure, it can be formed by one patterning, and no separate alignment is required.

Secondly, the connecting portion of the discharge sustaining electrode is spaced apart from the center of the discharge cell in which a relatively large amount of visible light is emitted. The aperture ratio on the center of the discharge cell is improved, thereby improving luminous luminance and luminous efficiency. In particular, according to the present invention, by providing a design specification for the separation distance of the connecting portion, it is possible to maintain the discharge stability while improving the brightness.

Although the present invention has been described with reference to the embodiments illustrated in the accompanying drawings, it is merely exemplary, and various modifications and equivalent other embodiments are possible from those skilled in the art to which the present invention pertains. You will understand the point. Therefore, the true scope of protection of the present invention should be defined by the appended claims.

Claims (5)

An upper substrate and a lower substrate disposed to face each other; A partition wall disposed between the upper substrate and the lower substrate to define a plurality of discharge cells together with the upper substrate and the lower substrate; A plurality of terminal electrodes extending across the discharge cells continuously arranged in one direction, and a plurality of protruding electrodes connected to the terminal electrodes extending inwardly of each discharge cell, and arranged to be paired with each other; Discharge sustaining electrodes; Address electrodes arranged to intersect the discharge sustain electrodes over discharge cells continuously arranged in different directions; An upper dielectric layer and a lower dielectric layer covering the discharge sustain electrodes and the address electrodes, respectively; A phosphor layer disposed in the discharge cells; And And a discharge gas encapsulated in the discharge cells. The protruding electrode, At least one electrode unit extending in one direction; And It includes a plurality of connecting portions for connecting the electrode portion and the terminal electrode, And the connection parts are spaced apart from the symmetry line passing through the center of each discharge cell in parallel with the connection parts. The method of claim 1, When the distance from the center line of the connection portion to the symmetry line is called the separation distance of the connection portion, the ratio of the separation distance to the discharge cell width is a plasma display panel, characterized in that 0.017 to 0.31. An upper substrate and a lower substrate disposed to face each other; A partition wall disposed between the upper substrate and the lower substrate to define a plurality of discharge cells together with the upper substrate and the lower substrate; At least two electrode portions each extending over the discharge cells continuously arranged in one direction and spaced apart from each other, and a plurality of connecting portions interconnecting the electrode portions, and a plurality of oppositely arranged pairs; Discharge sustaining electrodes; Address electrodes arranged to intersect the discharge sustain electrodes over discharge cells continuously arranged in different directions; An upper dielectric layer and a lower dielectric layer covering the discharge sustain electrodes and the address electrodes, respectively; A phosphor layer disposed in the discharge cells; And And a discharge gas encapsulated in the discharge cells. And the connection parts are spaced apart from the symmetry line passing through the center of each discharge cell in parallel with the connection parts. The method of claim 1, When the distance from the center line of the connection portion to the symmetry line is called the separation distance of the connection portion, the ratio of the separation distance to the discharge cell width is a plasma display panel, characterized in that 0.017 to 0.31. The method according to claim 1 or 3, And the discharge sustain electrodes are formed of a metal material.

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