KR100590085B1 - Plasma display panel - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display panel having an electrode structure that is advantageous for realizing a higher density, high luminance display.

According to the present invention, a plasma display panel includes: a first substrate and a second substrate disposed to face each other; Address electrodes formed on the first substrate in parallel with one direction; A plurality of discharges including first partition members disposed in parallel with the address electrodes in a space between the first substrate and the second substrate, and second partition members disposed in a direction crossing the address electrodes; Partition walls defining cells; Phosphor layers formed in the discharge cells; Between the first substrate and the second substrate, the first electrodes and the second electrodes are formed to extend in parallel with the second partition wall member constituting each discharge cell in parallel with the second partition member ; And third electrodes disposed between the pair of first and second electrodes adjacent to each other and formed to pass through the discharge cell inner space across the first partition members.

Plasma, Display, Counter Discharge, Front Panel Bulkhead

Description

Plasma Display Panel {PLASMA DISPLAY PANEL}

1 is a graph schematically showing a voltage distribution between a cathode and an anode in a typical glow discharge.

2 is a partially exploded perspective view illustrating a plasma display panel according to an embodiment of the present invention.

3 is a partial plan view schematically illustrating a structure of an electrode and a discharge cell in a plasma display panel according to an exemplary embodiment of the present invention.

4 is a partial cross-sectional view taken along line A-A combining the plasma display panel shown in FIG. 1.

5 and 6 are partial cross-sectional views of a plasma display panel according to another embodiment of the present invention.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display panel, and more particularly, to a plasma display panel having an electrode structure advantageous for realizing a high density and high luminance display.

In general, a plasma display panel (hereinafter referred to as a 'PDP') is used to implement an image using visible light generated by a vacuum ultraviolet ray (VUV) emitted from a plasma obtained through gas discharge. Display element. Such a PDP can realize an ultra-large screen of 60 inches or more with a thickness of only 10 cm or less, and is a self-luminous display device such as a CRT. In addition, the manufacturing method is simpler than LCD, and thus has advantages in terms of productivity and cost.

The structure of the PDP has been developed for a long time since the 1970s, and the structure generally known is a three-electrode surface discharge type structure. The three-electrode surface discharge type structure consists of one substrate including two electrodes located on the same surface and another substrate including address electrodes vertically spaced apart from each other at a predetermined distance therebetween, with a discharge gas enclosed therebetween. Structure. In general, the presence or absence of the discharge is determined by the discharge of the address electrode facing the scan electrode independently connected to each line, and the sustain discharge indicating the luminance is performed by two electrode groups located on the same plane. .

PDP uses a glow discharge to make visible light visible to humans, which takes several steps to reach the human eye after the glow discharge occurs. That is, when a glow discharge occurs, an excited gas is generated by collision between electrons and gases, and ultraviolet rays are generated from the excited gas. Ultraviolet rays collide with the phosphor in the discharge cell to generate visible light, and the visible light passes through the transparent substrate on the front surface and reaches the human eye. This step results in a significant loss of input power.

Glow discharges are usually obtained by applying a voltage above the discharge start voltage between two electrodes under a low atmospheric pressure (<1 atm). The discharge start voltage is a function of the type of gas, the atmospheric pressure, and the distance between electrodes. In the case of AC discharge, in addition to these three, the discharge start voltage is also affected by the dielectric capacitance (dielectric constant, electrode area, dielectric thickness) and the frequency of the applied voltage.

Although a very high voltage is required to initiate the discharge, the voltage distribution between the cathode and the anode is distorted as shown in FIG. 1 due to the difference in the space charge generated around the cathode and the anode once the discharge occurs. FIG. 1 shows that most of the voltage is being consumed around two electrodes, that is, in areas called cathode sheath and anode sheath, and in the relatively positive column region. It can be seen that the amount of voltage is small. In particular, the glow discharge generated in the PDP is known that the voltage consumed in the cathode sheath is much higher than the voltage of the anode sheath.

The emission of visible light in the phosphor is caused by the collision of the ultraviolet light with the phosphor, and the ultraviolet light is generated when the energy level is changed from the excited state of Xen to the ground state of Xen. . On the other hand, xenon Xe in an excited state is made by collision between Xen in stable state and electrons. Therefore, in order to increase the ratio of generating visible light among input energy, that is, luminous efficiency, the electron heating efficiency must be increased.

In general, since the electron heating efficiency in the positive column region is higher than the electron heating efficiency in the cathode sheath region, the improvement of the PDP luminous efficiency is possible by increasing the positive column region. Since the sheath region has almost the same thickness under the same pressure, it is necessary to increase the length of the discharge in order to increase the luminous efficiency.

In the case of a PDP having a three-electrode structure, discharge is initiated in the region between the two electrodes closest to the center of the discharge cell, after which the discharge moves to the edge region of the electrode. The discharge occurs in the center region because the discharge start voltage in this region is low. In general, the discharge start voltage is a function of the product of the pressure and the distance between the electrodes, and the PDP operating region is located to the right of the minimum value of the Paschen curve. Once the discharge is initiated, the discharge is maintained under a voltage much lower than the discharge start voltage due to the formation of space charge, and the voltage between the two electrodes gradually decreases with time. After the start of the discharge, the intensity of the electric field is weakened as ions and electrons accumulate in the central region, and the discharge disappears in this region.

Cathode spots and anode spots move over time in areas free of surface charge, ie around the electrode edges. At this time, since the voltage applied between the two electrodes decreases with time, strong discharge occurs in the center region of the discharge cell (low light emitting efficiency), and weak discharge occurs near the edge of the discharge cell (high light emitting efficiency). . Based on the same principle, the conventional three-electrode surface discharge structure has a low ratio used for heating electrons among the input energy, resulting in low luminous efficiency.

In order to overcome the weakness of the three-electrode structure, a method of increasing the distance between the display electrodes may be considered, but this causes an increase in the discharge start voltage.

The present invention has been made to solve the above problems, the object of which is to provide a discharge discharge to the opposite discharge, while having a different electrode between the electrodes involved in the sustain discharge to lower the discharge start voltage while increasing the luminous efficiency plasma It is to provide a display panel.

Plasma display panel according to the present invention,

A first substrate and a second substrate disposed to face each other;

Address electrodes formed on the first substrate in parallel with one direction;

A plurality of discharges including first partition members disposed in parallel with the address electrodes in a space between the first substrate and the second substrate, and second partition members disposed in a direction crossing the address electrodes; Partition walls defining cells;

Phosphor layers formed in the discharge cells;

Between the first substrate and the second substrate, the first electrodes and the second electrodes are formed to extend along the direction parallel to the second partition wall members constituting the discharge cells and alternately disposed field; And

And third electrodes disposed between the pair of first and second electrodes adjacent to each other and formed to pass through the discharge cell inner space across the first partition members.

Each of the first electrodes and the second electrodes has an outer surface surrounded by a dielectric layer, and the first electrodes and the second electrodes and the second partition wall members corresponding to the first electrodes and the second electrodes are disposed in a plane perpendicular to the longitudinal direction. Each cross section cut may have a substantially identical symmetric centerline.

The first electrodes and the second electrodes may be formed to have a longer length in a direction perpendicular to the substrate than a length in a direction parallel to the substrate in a quadrangular cross section cut in a plane perpendicular to the length direction. Do.

MgO passivation layers are formed on side surfaces of the first and second electrodes that face at least internal spaces of the discharge cells. This MgO protective film may have visible light impermeability.

Each of the third electrodes has an outer surface surrounded by a dielectric layer, a thickness of a dielectric layer formed on a surface of the third electrode facing the first electrode and the second electrode, and a surface of the third electrode facing the first substrate. The thickness of the dielectric layer formed on the same may be formed.

The third electrodes may be formed in a square shape in a cross section cut in a plane perpendicular to the longitudinal direction.

The third electrodes may be disposed to correspond to the middle or lower ends of the first electrode and the second electrode with respect to the height direction of the first electrode and the second electrode between the first substrate and the second substrate.

The third electrodes are formed such that at least an outer surface exposed to the inner space of the discharge cell is surrounded by an MgO protective film. The MgO protective film may have visible light impermeability.

The third electrodes may be formed to penetrate the first partition member.

The first partition member and the second partition member are formed to protrude toward the second substrate surface adjacent to the first substrate.

The second substrate is formed with a third partition member protruding toward the first substrate surface adjacent to the second substrate in a shape corresponding to the first partition member, and corresponding to the second partition member. The fourth partition member is formed so as to protrude toward the first substrate surface adjacent to the second substrate.

Each of the first electrode and the second electrode is positioned between the second partition member and the fourth partition member, and the third electrode is positioned between the first partition member and the third partition member.

A phosphor layer may be formed in an area of the second substrate partitioned by the third and fourth partition members.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and like reference numerals designate like elements throughout the specification.

2 is a partially exploded perspective view illustrating a plasma display panel according to an embodiment of the present invention, and FIG. 3 is a partial plan view schematically showing the structure of an electrode and a discharge cell in the plasma display panel according to an embodiment of the present invention. 4 is a partial cross-sectional view taken along line AA of the plasma display panel shown in FIG. 1.

Referring to the drawings, the PDP according to the present embodiment is basically described as a first substrate 10 (hereinafter referred to as a 'back substrate') and a second substrate 20 (hereinafter referred to as a 'front substrate'). ) Are formed to face each other at predetermined intervals, and a plurality of discharge cells 18 are partitioned into partitions 16 and 26 in the spaces between the substrates 10 and 20. In the discharge cell 18, phosphor layers 19 and 29, which absorb ultraviolet rays and emit visible light, are formed along the partition walls and the bottom surface, and discharge gases (for example, xenon and neon) to cause plasma discharge. (Mixed gas containing Ne) and the like.

Address electrodes 12 are formed on one surface of the rear substrate 10 opposite to the front substrate 20 in one direction (y-axis direction of the drawing), and cover the address electrodes 12 to cover the rear substrate 10. The dielectric layer 14 is formed all over the inner surface. The address electrodes 12 are formed in parallel with each other while maintaining a distance (x-axis direction) corresponding to the other address electrodes 12 and the discharge cells 18.

The partition walls 16 and 26 protrude toward the rear substrate 10 adjacent to the rear substrate 10 and protrude toward the rear substrate 10 adjacent to the rear substrate 10. It consists of a front plate partition wall 26.

The back plate partition wall 16 is formed on the dielectric layer 14 formed on the back substrate 10. In the present embodiment, the back plate partition wall 16 is arranged in a direction parallel to the address electrode 12. And a second partition member 16b formed to intersect the first partition member 16a and partitioning each discharge cell 18 into an independent discharge space. The front plate partition wall 26 may include a third partition member 26a having a shape corresponding to the first partition member 16a and a fourth partition member having a shape corresponding to the second partition member 16b. 26b). Accordingly, the third partition wall member 26a and the fourth partition wall member 26b are formed in the direction crossing each other to form a region 28 corresponding to each discharge cell 18 on the front substrate 20.

On the other hand, between the rear substrate 10 and the front substrate 20, corresponding to the second partition member (16b) constituting one side of each discharge cell 18 in parallel with this direction (x-axis direction in the drawing) Along the first electrode 31 and the second electrode 32 is formed long. In the present exemplary embodiment, the first electrodes 31 and the second electrodes 32 are alternately corresponding to each of the second partition members 16b and disposed to pass over the second partition members 16b. As a reference, the discharge cells 18 adjacent to each other in the longitudinal direction (the y-axis direction of the drawing) of the address electrode 12 may be used as a reference.

In addition, a third electrode 33 is disposed between each of the pair of first electrodes 31 and the second electrodes 32 adjacent to each other. The third electrodes 33 are formed to pass through the inside of the discharge cell 18 across the first partition member 16a.

At this time, the third electrode 33 serves to select the discharge cells 18 to be turned on by participating in the discharge of the address section together with the address electrode 12, and the first electrode 31 and the second electrode 32. ) Is involved in the discharge of the maintenance section and serves to display the screen. However, since the electrodes may have different roles depending on the signal voltage applied thereto, the present invention does not need to be limited to the above.

Referring to FIG. 3, each discharge cell 18 is divided into two regions 18a and 18b by the third electrode 33, and the first electrode of each of the regions 18a and 18b in the discharge sustaining period. A sustain discharge occurs between the 31 and the second electrode 32. That is, the third electrode 33 crossing the discharge cell 18 forms wall charges after the address discharge, and is held between the pair of first electrodes 31 and the second electrode 32 disposed on both sides thereof. The discharge start voltage is lowered because it helps the discharge occur.

Referring to FIG. 4, in the present embodiment, the first electrode 31 and the second electrode 32 and the second partition wall members 16b corresponding to them are perpendicular to the longitudinal direction (the x-axis direction in the drawing). Each cross section cut into a plane (eg, a quadrilateral cross section) has substantially the same axis of symmetry L. In this way, the first electrode 31 and the second electrode 32 can participate in the pair of discharge cells 18 adjacent to each other in the direction parallel to the address electrode 12.

In addition, in the present embodiment, the first electrode 31 and the second electrode 32 have a cross section cut in a plane perpendicular to the longitudinal direction than the length w1 in a direction parallel to the surfaces of the substrates 10 and 20. The length h1 in the direction perpendicular to the plane may be longer, and the third electrodes 33 may have a shape corresponding to the first and second electrodes 31 and 32, but the length may be longer. A cross section (for example, a square cross section) cut in a plane perpendicular to the direction has a length w2 in the direction parallel to the substrate 10 and 20 planes and a length in the direction perpendicular to the substrate 10 and 20 planes ( h2) may be formed identically (see FIG. 5). The lengths w2 and h2 of the third electrode 33 are preferably shorter than the lengths h1 of the first and second electrodes 31 and 32. The third electrode 33 may be disposed corresponding to various heights of the first and second electrodes 31 and 32 with respect to the height direction (z-axis direction) between the substrates 10 and 20. Therefore, the opposite discharge can be induced more easily between the first and second electrodes 31 and 32, thereby obtaining a high luminous efficiency. At this time, the third electrode 33 is formed in a square cross section, and minimizes the interference of the opposite discharge occurring between the first and second electrodes 31 and 32 to prevent the address discharge on the surface opposite to the address electrode 12. It is preferable to prevent and induce an address discharge on the first and second electrodes 31 and 32 side.

The outer surfaces of the first and second electrodes 31 and 32 and the third electrodes 33 are surrounded by the dielectric layers 34 and 35. These first, second, and third electrodes 31, 32, and 33 may be manufactured by a thick film ceramic sheet (TFCS) method. That is, the electrode unit including the first and second electrodes 31 and 32 and the third electrode 33 may be separately manufactured and then coupled to the back substrate 10 having the partition wall 16 formed thereon. At this time, the electrode is coated with a ceramic (ceramic).

The MgO passivation layer 36 may be formed on the surfaces of the dielectric layers 34 and 35 covering the first and second electrodes 31 and 32 and the third electrode 32. In particular, the MgO passivation layer 36 may be formed in a portion exposed to the plasma discharge occurring in the discharge space inside the discharge cell 18. In the present embodiment, since the first and second electrodes 31 and 32 and the third electrode 33 are not formed on the front substrate 20, the MgO passivation layer is applied to the dielectric layers 34 and 35 covering the electrodes. Reference numeral 36 may use MgO having characteristics of visible light impermeability. Visible light-transmissive MgO has a much higher secondary electron emission coefficient value than visible light-transmissive MgO, thus further lowering the discharge start voltage.

In the present embodiment, the thickness δl of the dielectric layer formed on the surface of the third electrode 33 facing the first and second electrodes 31 and 32 and the third electrode 33 facing the back substrate 10. It is preferable that the thickness δh of the dielectric layer formed on the surface is the same. In this way, address discharge is prevented from occurring on the undersides of the address electrode 12 and the third electrode 32 together with the third electrode 33 having a square cross-section, so that the address electrode 12 and the third electrode 32 are separated. It happens on the side.

As such, the first electrode 31 and the second electrode 32 having the dielectric layer 34 and the MgO protective layer 36 may be formed between the second partition member 16b and the fourth partition member 26b. It is located alongside (16b, 26b). However, the third electrode 33 having the dielectric layer 35 and the MgO passivation layer 36 is positioned to intersect these partition members 16a and 26a between the first partition member 16a and the third partition member 26a. do.

In particular, a groove is formed in a part of the first partition member 16a to form the third electrode 33, and the third electrode 33 having the dielectric layer 35 and the MgO passivation layer 36 coated thereon is formed in the groove. Can be made to fit. In this case, the third electrode 33 and the first and second electrodes 31 and 32 may have the same distance measured from the back substrate 10 and surround the third electrode 33. The top surface of the dielectric layer 35 may be formed to substantially coincide with the top surface of the first partition member 16a. The third electrode 33 may be formed to penetrate the first partition member 16a.

The first and second electrodes 31 and 32 and the third electrode 33 are preferably made of a metal electrode having excellent electrical conductivity.

On the other hand, the phosphor layer 29 is formed in the region 28 of the front substrate 20 partitioned by the third partition member 26a and the fourth partition member 26b formed adjacent to the front substrate 20. Can be. The phosphor layer 29 may apply a dielectric layer on the front substrate 20, form a front plate partition 26, and then apply a phosphor layer on the dielectric layer, and selectively apply the dielectric layer to the front substrate 20. Instead, the front plate partition wall 26 may be formed on the front substrate 20 to apply a phosphor layer. Furthermore, the front substrate 20 may be etched to match the shape of the discharge cell 18 and then a phosphor layer may be coated thereon. At this time, the front plate partition 26 is made of the same material as the front substrate 20.

In the above case, the phosphor layer 29 formed on the front substrate is used to generate visible light by absorbing vacuum ultraviolet rays (VUV) directed toward the front substrate 20 after discharge is generated in the discharge cell 18. The phosphor layer 29 needs to be able to transmit visible light. For this purpose, the phosphor layer 29 may be formed on the front substrate 20 to have a thickness thinner than that of the phosphor layer 19 formed on the rear substrate 10. have.

In this way, the luminous efficiency can be improved by minimizing the loss of vacuum ultraviolet rays.

In the above embodiment, the third electrode 33 is formed so as to correspond to the first and second electrodes 31 and 32 with respect to the height direction (z-axis direction) between the substrates 10 and 20. To illustrate.

5 and 6 are partial cross-sectional views of a plasma display panel according to another embodiment of the present invention.

In comparison with the above-described embodiment, the embodiment of FIG. 5 has a lower end of the first and second electrodes 31 and 32 with respect to the height direction (z-axis direction) between the substrates 10 and 20. (I.e., the rear substrate side), the embodiment of FIG. 6 shows that the third electrode 33 is the first and second electrodes with respect to the height direction (z-axis direction) between the substrates 10 and 20. It illustrates that disposed in the middle of (31, 32).

In this case, the embodiment of FIG. 5 reduces the address discharge voltage by shortening the distance between the third electrode 33 and the address electrode 12, compared to the embodiment of FIG. 6, and the embodiment of FIG. As a result, more wall charges are accumulated between the first and second electrodes 31 and 32 to lower the discharge start voltage.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications or changes can be made within the scope of the claims and the detailed description of the invention and the accompanying drawings. In addition, it is natural that it belongs to the scope of the present invention.

As described above, according to the plasma display panel according to the present invention, by providing the electrodes involved in the sustain discharge in opposite postures on both sides of the discharge cell, and disposing the electrodes involved in the address discharge therebetween, the sustain discharge becomes the opposite discharge. While forming a short interval between the electrodes for the start of the discharge to reduce the discharge start voltage, it is also effective to increase the luminous efficiency by forming a long gap between the electrodes involved in the sustain discharge after the start of the discharge.

Claims (16)

Front substrate; A rear substrate disposed to face the front substrate; Address electrodes formed on the rear substrate in parallel in one direction; A plurality of discharge cells are included in a space between the rear substrate and the front substrate, the first partition members disposed in parallel with the address electrodes and the second partition members disposed in a direction crossing the address electrodes. Partition wall; Phosphor layers formed in the discharge cells; First and second electrodes formed alternately between the rear substrate and the front substrate so as to be elongated in parallel with the second partition members constituting the discharge cells and arranged in parallel with each other; And And third electrodes disposed between the pair of first and second electrodes adjacent to each other, the third electrodes being formed to pass through the discharge cell inner space across the first partition members. The method of claim 1, Each of the first electrodes and the second electrodes has an outer surface surrounded by a dielectric layer. The method of claim 1, And cross-sections of the first electrodes and the second electrodes and the second partition wall members corresponding to the first electrodes and the second electrodes, respectively, having substantially the same symmetric center line. The method of claim 1, The first electrodes and the second electrodes are plasma displays having a longer length in a direction perpendicular to the substrate than a length in a direction parallel to the substrate, in a quadrangular cross section cut in a plane perpendicular to the length direction. panel. The method of claim 1, And the MgO passivation layer on at least one side of the first electrode and the second electrode facing the inner space of each of the discharge cells. The method of claim 1, Each of the third electrodes has an outer surface surrounded by a dielectric layer. The method of claim 6, And the dielectric layer has a thickness formed on a surface facing the first electrode and a second electrode and a thickness formed on a surface facing the rear substrate. The method of claim 1, And the third electrodes are formed in a square shape in a cross section cut in a plane perpendicular to the longitudinal direction. The method of claim 8, And the third electrodes are disposed corresponding to the middle of the first electrode and the second electrode with respect to the height direction of the first electrode and the second electrode between the rear substrate and the front substrate. The method of claim 8, And the third electrodes are disposed corresponding to lower ends of the first electrode and the second electrode with respect to the height direction of the first electrode and the second electrode between the rear substrate and the front substrate. The method of claim 1, And the third electrodes have an MgO passivation layer surrounding at least an outer surface exposed to an inner space of the discharge cell. The method of claim 5 or 11, The MgO passivation layer has a visible light impermeability. The method of claim 1, And the first and second barrier members are formed to protrude toward the front substrate surface adjacent to the rear substrate. The method of claim 1, The front substrate is formed with a third partition member protruding toward the rear substrate surface adjacent to the front substrate in a shape corresponding to the first partition member, And a fourth partition wall member protruding toward the rear substrate surface adjacent to the front substrate in a shape corresponding to the second partition wall member. The method of claim 14, Each of the first electrode and the second electrode is positioned between the second partition member and the fourth partition member, and the third electrode is positioned between the first partition member and the third partition member. panel. The method of claim 14, And a phosphor layer formed in a region of the front substrate partitioned by the third and fourth partition members.

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