KR100578973B1 - Plasma display panel - Google Patents

Abstract

The present invention relates to a plasma display panel which induces sustain discharge into a counter discharge and increases luminous efficiency while facilitating address discharge while lowering a discharge start voltage.

A plasma display panel according to the present invention comprises: 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 discharge cells are partitioned in a space between the first substrate and the second substrate, the first partition member disposed in a direction parallel to the address electrode and the second partition member disposed in a direction crossing the address electrode; Partition wall to make; A phosphor layer formed in each of the discharge cells; First electrodes between the first substrate and the second substrate, the first electrodes being formed to extend in parallel with the second partition members constituting the discharge cells; Disposed between the pair of first electrodes adjacent to each other, and including second electrodes formed to pass through the discharge cell inner space across the first partition member, wherein each of the address electrodes includes: Address discharge induction parts formed correspondingly between the first electrode and the second electrode, and connection parts electrically connected to each other between the address discharge induction parts.

Plasma, Display, Counter discharge, Front panel bulkhead, Address electrode, Address discharge induction part, Connection part

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 with the plasma display panel shown in FIG.

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 capacitance of the dielectric (dielectric constant, electrode area, dielectric thickness) and the frequency of the applied voltage affect the discharge start voltage.

In order to start the discharge, a very high voltage is required, but once the discharge occurs, 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. 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 the input energy, that is, the 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 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.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and provides a plasma display panel which induces sustain discharge into a counter discharge to increase luminous efficiency while reducing discharge start voltage and to facilitate address discharge.

Plasma display panel according to the present invention,

A first substrate and a second substrate facing each other;

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

A plurality of discharge cells are partitioned in a space between the first substrate and the second substrate, the first partition member disposed in a direction parallel to the address electrode and the second partition member disposed in a direction crossing the address electrode; Partition wall to make;

A phosphor layer formed in each of the discharge cells;

First electrodes between the first substrate and the second substrate, the first electrodes being formed to extend in parallel with the second partition members constituting the discharge cells;

A second electrode disposed between the pair of first electrodes adjacent to each other and formed to pass through the discharge cell internal space across the first partition member;

Each of the address electrodes,

Address discharge induction parts formed correspondingly between the first electrode and the second electrode, and connection parts electrically connected to each other between the address discharge induction parts.

The width WA1 of the connection portion formed in the direction perpendicular to the longitudinal direction of the address electrode is formed to be narrower than the width WA2 of the address discharge induction portion formed in this direction.

Two address discharge induction units are disposed in each discharge cell. The address discharge induction part is formed in a quadrangle corresponding between the first electrode and the second electrode arranged in parallel with each other.

The address discharge induction part forms a first gap δ1 with a first electrode and a second gap δ2 in the extending direction of the address electrode. The first gap δ1 is preferably larger than the second gap δ2 in order to prevent miss addressing.

Each of the first electrodes has an outer surface surrounded by a dielectric layer, and cross-sections perpendicular to the longitudinal direction of the first electrodes and the second partition members corresponding to the first electrodes have substantially the same symmetric center line.

Preferably, the first electrodes have a length in a direction perpendicular to the substrate longer than a length in a direction parallel to the substrate in a vertical cross section with respect to the length direction thereof.

MgO passivation layers are formed on at least side surfaces of the first electrodes facing the inner spaces of the respective discharge cells.

Each of the second electrodes has an outer surface surrounded by a dielectric layer, and the dielectric layer has a thickness formed on the surface of the second electrode facing the first substrate more than the thickness formed on the side of the second electrode facing the first electrode. It is preferable to form thickly.

It is preferable that the second electrodes have a length in a direction perpendicular to the substrate longer than a length in a direction parallel to the substrate in a cross section perpendicular to the longitudinal direction thereof.

The second electrodes have an MgO passivation layer formed around at least an outer surface exposed to an inner space of the discharge cell, and the MgO passivation layer has visible light impermeability.

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

The second substrate is formed with a third partition member projecting toward the first substrate in a shape corresponding to the first partition member, and protruding toward the first substrate in a shape corresponding to the second partition member. A fourth partition member is formed.

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

The phosphor layer is formed in an area of the second substrate partitioned by the third partition member and the fourth partition member.

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.

Referring to the drawings, the PDP according to the present embodiment basically includes a first substrate 10 (hereinafter referred to as a 'back substrate') and a second substrate 20 (hereinafter referred to as a 'front substrate'). The cells are disposed to face each other at predetermined intervals, and a plurality of discharge cells 18 are partitioned by partition walls 16 and 26 in the space between the rear substrate 10 and the front substrate 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 including Ne) and the like.

Address electrodes 12 are formed along one direction (y-axis direction of the drawing) on the opposite surface of the front substrate 20 of the rear substrate 10, and cover the entire address surfaces of the rear substrate 10 while covering the address electrodes 12. A dielectric layer 14 is formed in the. The address electrodes 12 are arranged 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 each discharge cell 18 in parallel with the direction (x-axis direction in the drawing) The first electrode 31 is formed to be long. In the present exemplary embodiment, since the first electrodes 31 correspond to each of the second partition members 16b one by one, the first electrodes 31 are disposed to pass over the second partition members 16b, so that the first electrodes 31 are parallel to the address electrodes 12. It can be a reference to distinguish the adjacent discharge cells 18 in the y-axis direction.

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

In this case, the second electrode 32 plays a role of selecting 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 electrodes 31 and 31 are connected to the second electrode. Together with the electrode 32 serves to display the screen by participating in the discharge of the holding section. 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 of the discharge cells 18 is divided into two regions 18a and 18b by the second electrode 32, and the pair is formed in each of the regions 18a and 18b in the discharge maintenance section. The sustain discharge is generated between the first electrodes 31 and 31 and the second electrode 32. That is, since the sustain discharge is caused between the second electrode 32 crossing the discharge cell 18 and the pair of first electrodes 31 and 31 arranged at both sides, the electrodes involved in the discharge holding are discharge cells. (18) The discharge gap between the two electrodes causing the discharge is reduced by almost half than that adjacent to the edges, respectively, and therefore driving can be performed even at a low discharge start voltage.

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

Further, in the present embodiment, the first electrodes 31 have a cross section cut in a plane perpendicular to the longitudinal direction and are perpendicular to the substrate 10 and 20 planes rather than the length w1 in a direction parallel to the substrate 10 and 20 planes. The length h1 in one direction may be longer, and the second electrode 32 may have a cross section cut in a plane perpendicular to the length direction than the length w2 in a direction parallel to the substrate surface. The length h2 in the vertical direction may be longer. Therefore, the opposite discharge can be induced more easily between the first and second electrodes 31 and 32, thereby obtaining a high luminous efficiency.

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

An MgO passivation layer 36 may be formed on the surfaces of the dielectric layers 34 and 35 respectively covering the first electrode 31 and the second 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 electrode 31 and the second electrode 32 are not formed on the front substrate 20, the dielectric layers 34 and 35 covering the first and second electrodes 31 and 32 may be used. The MgO protective film 36 applied to the film may be made of MgO having visible light impermeability. This visible light-transmissive MgO has a much higher secondary electron emission coefficient value than the visible light-transmissive MgO, and thus the discharge start voltage can be further lowered.

In the second electrode 32 of the present embodiment, the second electrode 32 facing the rear substrate 10 rather than the thickness δl of the dielectric layer formed on the surface of the second electrode 32 facing the first electrode 31. The thickness δh of the dielectric layer formed on the surface of the film is formed thicker. In this way, address discharge is prevented from occurring at the bottom of the address electrode 12 and the second electrode 32 and is generated between the side of the second electrode 32 and the address electrode 12.

Thus, the first electrode 31 having the dielectric layer 34 and the MgO protective film 36 is formed between the second and fourth partition members 16b and 16b between the second and fourth partition members 16b and 26b. 26b). However, the second electrode 32 having the dielectric layer 35 and the MgO protective film 36 is formed between the first and third partition members 16a and 26a between the first partition member 16a and the third partition member 26a. Positioned to intersect.

In particular, in order to form the second electrode 32, a groove is formed in a part of the first partition member 16a, and the second electrode 32 having the dielectric layer 35 and the MgO passivation layer 36 coated thereon is formed in the groove. It can be made by inserting. In this case, the second electrode 32 and the first electrode 31 may be formed to have the same distance measured from the back substrate 10, and the dielectric layer 35 surrounding the second electrode 32. An upper end surface of the first barrier rib member 16a may be formed to substantially coincide with an upper end surface of the first partition member 16a. The second electrode 32 may be formed to penetrate the first partition member 16a.

It is preferable that the first electrode 31 and the second electrode 32 are 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 conform to the shape of the discharge cell 18 and then a phosphor layer may be applied 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 20 is used to generate visible light by absorbing vacuum ultraviolet rays (VUV) directed toward the front substrate 20 after the 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.

Referring again to the address electrode 13 with reference to FIG. 2, the address electrodes 12 of the present embodiment are each address discharge induction part 12a corresponding to the two regions 18a and 18b of the discharge cell 18. And a connecting portion 12b for electrically connecting the address discharge inducing portions 12a to each other, and is formed long in one direction (y-axis direction).

The address discharge induction part 12a is formed in the regions 18a and 18b corresponding to the first electrode 31 and the second electrode 32, and the connection part 12b is the second electrode 32 and the partition wall 16b. And corresponding discharge between the first electrode 31 and the second electrode 32 while preventing address discharge from occurring below the second electrode 32 (as shown in FIG. 4). Address discharge is induced to occur in the two regions 18a and 18b of the cell 18. As a result, a large amount of wall charges are formed in the side dielectric layers of the first electrode 31 and the second electrode 32, thereby causing a sustain discharge.

To this end, the connection part 12b has an address discharge induction part 12a having a width WA1 formed in a direction perpendicular to the length direction (y axis direction) of the address electrode 12 (x axis direction). It is formed narrower than the width WA2. Relatively, the address discharge induction part 12a is formed in a wide width WA1 and the connection part 12b is formed in a narrow width WA2. Two address discharge induction portions 12a formed with a wide width WA2 are disposed in each of the discharge cells 18 to facilitate address discharge compared to the connection portion 12b.

The address discharge induction part 12a may be formed in various ways. In this embodiment, the address discharge induction part 12a is formed in a quadrangle corresponding to the first electrode 31 and the second electrode 32 arranged in parallel with each other. This rectangle enables the address discharge induction part 12a having the largest area in the corresponding areas 18a and 18b between the first and second electrodes 31 and 32 in the rectangular discharge cell 18. Accordingly, the address discharge induction part 12a may be formed in a shape corresponding to the shape of the discharge cell 18 as appropriate.

The address discharge induction part 12a forms a first gap δ1 between the first electrode 31 and the second electrode 32 in the extending direction (y axis direction) of the address electrode 12. The second gap δ2 is formed in between. In addition, the first interval δ1 prevents miss addressing of other adjacent discharge cells 18, and the second interval δ2 prevents address discharge from occurring immediately below the second electrode 32, and thus, the first gap. It is preferable that (δ1) is formed larger than the second gap (δ2).

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. It goes without saying that it belongs to the scope of the present invention.

As described above, according to the plasma display panel according to the present invention, the sustain discharge is induced to the opposite discharge, thereby lowering the discharge start voltage and causing two sustain discharges in one discharge cell, thereby increasing the luminous efficiency. The electrode is formed of a large area address discharge induction part and a connection part connecting the same, and the address discharge induction part is corresponded between the first electrode and the second electrode to accumulate a large amount of wall charges on the first electrode and the second electrode side. There is an effect of making the discharge easier.

Claims (14)

A first substrate and a second substrate facing each other; Address electrodes formed on the first substrate in parallel with one direction; A plurality of discharge cells are partitioned in a space between the first substrate and the second substrate, the first partition member disposed in a direction parallel to the address electrode and the second partition member disposed in a direction crossing the address electrode; Partition wall to make; A phosphor layer formed in each of the discharge cells; First electrodes between the first substrate and the second substrate, the first electrodes being formed to extend in parallel with the second partition members constituting the discharge cells; A scan electrode disposed between the pair of first electrodes adjacent to each other and formed to pass through an inner space of the discharge cell across the first partition member to form an opposite discharge structure with the sustain electrode; , Each of the address electrodes, And an address discharge induction part formed correspondingly between the first electrode and the second electrode, and connecting parts electrically connected to each other between the address discharge induction parts. The method of claim 1, And a width WA1 of the connection portion formed in a direction perpendicular to the length direction of the address electrode is smaller than a width WA2 of the address discharge induction portion formed in such a direction. The method of claim 1, And two address discharge induction parts in each discharge cell. The method of claim 1, And the address discharge inducing part is formed in a quadrangle corresponding to the first electrode and the second electrode disposed in parallel to each other. The method of claim 1, And the address discharge inducing part forms a first gap δ1 with a first electrode in a direction in which the address electrode extends. The method of claim 1, And the address discharge inducing part forms a second gap (δ2) with a second electrode in a direction in which the address electrode extends. The method of claim 1, The address discharge induction part forms a first gap δ1 with a first electrode in the extending direction of the address electrode, forms a second gap δ2 with a second electrode, and forms the first gap δ1 with a second gap. A plasma display panel formed larger than the gap δ2. The method of claim 1, Each of the first electrodes has an outer surface surrounded by a dielectric layer. The method of claim 1, And the first electrodes have a length in a direction perpendicular to the substrate longer than a length in a direction parallel to the substrate in a vertical cross section with respect to the length direction thereof. The method of claim 1, Each of the second electrodes has an outer surface surrounded by a dielectric layer. The method of claim 1, And the second electrodes have a length in a direction perpendicular to the substrate longer than a length in a direction parallel to the substrate in a cross section perpendicular to the length direction thereof. The method of claim 1, The second substrate is formed with a third partition member projecting toward the first substrate in a shape corresponding to the first partition member, and protruding toward the first substrate in a shape corresponding to the second partition member. And a fourth partition member which is formed. The method of claim 1, The first electrode is positioned between the second partition member and the fourth partition member, the second electrode is positioned between the first partition member and the third partition member. The method of claim 1, And a phosphor layer formed in an area of the second substrate partitioned by the third and fourth partition members.

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