JP2000353473A - Member for plasma display and plasma display using same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce deterioration in luminous efficiency by suppressing a voltage drop of a discharge voltage to reduce a load on a driver circuit, by causing the line resistance of a scanning electrode to differ from that of a maintenance electrode and the width of a bus electrode layer of the scanning electrode to differ from that of a bus electrode layer of the maintenance electrode. SOLUTION: A transparent electrode layer and a bus electrode layer are formed on a glass substrate, thus making up a scanning electrode and a maintenance electrode. To suppress a voltage drop of a discharge voltage, it is important that line resistance of the scanning electrode is different from that of the maintenance electrode. There are methods for causing the line resistance of the scanning electrode to differ from that of the maintenance electrode, such as to change the electrode material, or the thickness or the width of the transparent electrode layer or of the bus electrode layer. However, from the viewpoint of effectiveness, front plate flatness, cost, etc., it is effective to cause the width of the bus electrode layer of the scanning electrode to differ from that of the bus electrode layer of the maintenance electrode. It is desirable to make the line resistance of the scanning electrode lower than the line resistance of the maintenance electrode, and therefore, the width of the bus electrode layer of the scanning electrode is made larger than the width of the bus electrode layer of the maintenance electrode.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display used for a large television or a computer monitor.

[0002]

2. Description of the Related Art In recent years, plasma displays have attracted attention as large displays. FIG. 4 is an exploded perspective view of a structural example of the plasma display, FIG. 5 is a cross-sectional view thereof, and FIG. 6 is a plan view of an electrode structure of the front plate. The plasma display is configured by bonding a front plate and a back plate. In the front plate, transparent electrode layers 101T and 102T made of ITO or tin oxide are formed on the back surface of the glass substrate 100. The transparent electrode layers 101T and 102T form a plurality of scan electrodes 101 and sustain electrodes 102 in a strip shape. A pulsed AC voltage of usually 10 kHz to several tens of kHz is applied between the adjacent scan electrode 101 and sustain electrode 102 to obtain a discharge for display, but the transparent electrode layers 101T, 102T
Is as high as several tens of ohms / cm @ 2 in sheet resistance and several tens of kilohms in line resistance, so that it is difficult to drive the printing voltage pulse sufficiently because it does not sufficiently rise. Therefore,
On the transparent electrode layer, a bus electrode layer (generally called a metal electrode layer because it is usually formed of a metal component) 101B, 102.
B is formed to lower the resistance value. A transparent dielectric layer 103 is coated on these electrodes. On the transparent dielectric layer 103, a protection layer 104 of MgO is further formed.

On the other hand, the back plate is formed with an address electrode 201 for writing display data on a glass substrate 200 and covered with a dielectric layer 202. On top of that, the partition 203
Are formed, and red 204R, green 204G, and blue 20R are formed between partition walls.
After applying the phosphor emitting each color of 4B, drying and baking are performed to form a phosphor layer.

[0004] The front plate and the rear plate are fitted and sealed so as to enable matrix display driving, and a rare gas composed of Ne, Xe, or the like is sealed in a gap between the members, as shown in FIG. As described above, the driving circuits such as the scanning driver IC and the data driver IC are mounted to configure the plasma display.

When a pulsed AC voltage is applied between the scan electrode 101 and the sustain electrode 102 adjacent to each other on the front panel, a surface discharge H1 occurs and plasma is formed. The ultraviolet light generated here excites the phosphor to emit visible light and obtain display light emission through the front plate. In actual panel driving, sustain discharge pulses are applied to the scan electrodes and sustain electrodes, which are discharge electrodes. When a discharge is to be generated, a voltage is applied between the address electrodes 201 on the rear panel to write data. A discharge (counter discharge) H2 is generated, and this discharge is maintained between the scan electrode and the sustain electrode on the front panel by the sustain pulse.

Here, since the bus electrode layer of the front panel is opaque, the portion where the bus electrode layer is formed does not transmit light, that is, it becomes a dead area for display light emission like the partition.

[0007] In particular, when the definition of a plasma display is increased, this problem becomes apparent. That is, in order to increase the number of pixels with a fixed screen size, it is necessary to reduce the size of one pixel. For example, in order to realize a 42-inch high-definition television (1920 × 1035 pixels) or a 23-inch OA monitor (XGA: 1024 × 768 pixels), it is necessary to reduce the pixel size to 450 μm square.

However, in the bus electrode layer, if the width of the electrode layer is reduced in accordance with the size of the pixel, the line resistance increases, the peak value of the discharge current at the time of discharge increases, and the peak value increases. Since a voltage drop occurs, the discharge voltage must be set higher to secure a margin, and the scan driver IC and data driver I
The load on C increases and the power consumption increases. Furthermore, when the size of the pixel is reduced, the discharge space becomes smaller, and the movement of the charged particles is suppressed, so that the discharge start voltage increases and the power consumption increases.

As means for solving this problem, Japanese Patent Application Laid-Open No. 7-29498 discloses a method in which the width of the electrode gap G1 of the front plate is gradually changed in the extension direction to determine when the surface discharge occurs. A proposal has been made to reduce the peak value of the discharge current by dispersing the time at which discharge occurs by delaying in order from the small side of G1. However, according to this method, the electrode gap G1
The width of the electrode gap G2, which should not be involved in the discharge, is narrowed by increasing the width of the electrode gap.
There is a problem that the margin of the discharge voltage becomes narrow.

[0010]

SUMMARY OF THE INVENTION The present invention reduces the load on a driver circuit such as a scan driver IC or a data driver IC by suppressing a voltage drop of a discharge voltage.
It is an object of the present invention to provide a member for a plasma display in which the luminous efficiency is less reduced even when the definition is increased with low power consumption and low cost, and a plasma display using the same.

[0011]

That is, the present invention relates to a plasma display member in which a scanning electrode and a sustaining electrode are arranged in parallel with each other, wherein the scanning electrode and the sustaining electrode have different line resistances. This is a display member.

According to the present invention, there is provided a member for a plasma display in which a scan electrode and a sustain electrode are arranged in parallel with each other, wherein the width of the bus electrode layer of the scan electrode and the width of the bus electrode layer of the sustain electrode are different. It is a member for a plasma display.

Further, the present invention is a plasma display using these plasma display members as a front plate.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in accordance with the procedure for manufacturing a plasma display.

(Front Plate) The glass substrate of the front plate, which is a member for a plasma display of the present invention, is a general soda-lime glass, a glass obtained by annealing a soda-lime glass, or a glass having a high strain point (for example, Asahi Glass Co., Ltd.). "PD-200"). As the size of the glass substrate, glass having a thickness of 1 to 5 mm can be preferably used.

A transparent electrode layer and a bus electrode layer are formed on a glass substrate to form a scan electrode and a sustain electrode. For suppressing the voltage drop of the discharge voltage, which is the object of the present invention, it is important that the scan electrodes and the sustain electrodes have different line resistances. In other words, the drive circuit to be connected is different between the scan electrode and the sustain electrode, and the allowable voltage load is also different. Therefore, it is important to set the line resistance according to this. Usually, a scan driver IC is connected to the scan electrode. However, since the scan driver IC is apt to receive the load of voltage application and is expensive, it is preferable that the line resistance of the scan electrode be lower than the line resistance of the sustain electrode.

Means for differentiating the line resistance between the scanning electrode and the sustaining electrode include changing the electrode material, thickness, and width of the transparent electrode layer or the bus electrode layer. It is most effective to make the widths of the bus electrode layer of the scanning electrode and the bus electrode layer of the sustain electrode different from the viewpoint of manufacturing cost and the like. Considering that it is preferable that the line resistance of the scan electrode is lower than the line resistance of the sustain electrode, the width of the bus electrode layer of the scan electrode is preferably larger than the width of the bus electrode layer of the sustain electrode. .

The transparent electrode layer can be obtained by forming a film of tin oxide or ITO and forming a pattern.
For film formation, tin oxide can be prepared by solution spraying or chemical vapor deposition.
TO can be performed by an evaporation method, a sputtering method, an ion plating method, or the like. Pattern formation can be performed by a lift-off method, a photo-etching method, or the like. As shown in FIGS. 1 and 2, the shape of the transparent electrode is wider than the metal electrode layer and parallel and linear.
In order to make the scanning electrode and the sustain electrode close to each other in the vicinity of the discharge region, there are some which protrude in a rectangular, trapezoidal, T-shaped or the like in the width direction of the electrode.

The bus electrode layer can be obtained by forming a film of silver, aluminum, copper, gold, nickel, platinum, or a material obtained by adding palladium to these on the transparent electrode layer, and forming a pattern. The pattern can be formed by a photoetching method, a screen printing method, a photolithography method using a photosensitive conductive paste, or the like. This metal electrode layer generally has a high reflectance, and the contrast of the screen is reduced due to the reflection of external light incident on the display screen.Therefore, in order to reduce the reflectance of the metal electrode surface on the display side and improve the contrast, Preferably, as shown in the sectional view of FIG. 3, the bus electrode layer is formed of two or more layers, and the display surface side is a black electrode layer. The material of the metal electrode layer of the black electrode layer is not particularly limited. However, since the line resistance is low and the reflectance is low, it is preferable that chromium is used in the deposition method and the sputtering method, and a photosensitive conductive paste is used. In the formation by photolithography, the black electrode layer is composed of ruthenium, chromium, cobalt, manganese,
It is preferable that the metal or the oxide selected from copper, silver, and nickel is a fired product of a photosensitive conductive paste containing at least one kind.

The distribution of visible light emitted when ultraviolet light generated by the discharge between the scanning electrode and the transparent electrode layer of the sustaining electrode excites the phosphor is highest at the center between the transparent electrodes and decreases as the distance from the center increases. Therefore, it is preferable that the bus electrode layer of the scan electrode and the bus electrode layer of the sustain electrode are disposed on the outermost sides of the respective electrodes. Further, since the bus electrode layer becomes dead area to shield the visible light to excite the phosphor, for each of the scan electrodes and the sustain electrodes, the width W _T of the width W _B and the transparent electrode layer of the bus electrode layer following conditions It is preferable to satisfy the following. W _B ≦ W _T × 2/3 Further, if the emission intensity distribution in the aperture region of one pixel is not symmetric, the luminance changes depending on the viewing direction of the display,
Since the luminous efficiency also tends to decrease, the center of the gap G1 between the scan electrode and the transparent electrode between the sustain electrodes is the center of the gap G3 between the scan electrode and the bus electrode between the sustain electrodes, as shown in the plan view of the electrode structure in FIG. Preferably, it is near the center.
In terms of aperture symmetry to be described later, it is preferably 0.6 to 1.7, and more preferably 0.8 to 1.3.

Next, a transparent dielectric layer is formed so as to cover the transparent electrode layer and the bus electrode layer. The transparent dielectric layer can be formed by a screen printing method, a coater method, or the like. As the material of the transparent dielectric, a material containing lead oxide, boron oxide, silicon oxide, or the like can be used.

Next, a protective layer is formed for the purpose of protecting the transparent dielectric layer and lowering the discharge voltage. The protective layer can be formed by an electron beam evaporation method, a reactive sputtering method, an ion plating method, or the like. Generally, an oxide of an alkaline earth metal can be used as a material for the protective layer. Especially Mg
O is suitable as a protective layer because it has excellent sputter resistance and a high secondary electron emission coefficient.

(Back Plate) As the substrate of the back plate, the same substrate as described above for the front plate can be used.

Next, an address electrode is formed. Address electrodes are silver, aluminum, copper, gold, nickel, tin oxide, IT
O or the like can be formed by screen printing or a photolithography method using a photosensitive conductive paste.

Further, a dielectric layer may be provided on the address electrode for stabilizing the discharge.

Next, a partition is formed. The partition can be formed in parallel with the address electrode by a sandblast method, a mold transfer method, a photolithography method, or the like. As a material for the partition, for example, a known glass material containing an oxide of silicon and boron can be used.

Next, a phosphor layer is formed. The phosphor layer can be formed between adjacent partitions by a photolithography method using a photosensitive phosphor paste, a dispenser method, a screen printing method, or the like. The phosphor material used in the present invention is, for example, red, Y ₂ O ₃ : Eu,
YVO ₄ : Eu, (Y, Gd) BO ₃ : Eu, Y ₂ O ₃ S:
Eu, γ-Zn ₃ (PO ₄ ) ₂ : Mn, green, Zn ₂ G
eO ₂ : Mn, BaAl ₁₂ O ₁₉ : Mn, Zn ₂ SiO ₄ :
Mn, LaPO ₄ : Tb, ZnS: Cu, Al, Zn ₂ S
iO ₄ : Mn, As, (ZnCd) S: Cu, Al, Zn
O: Zn, blue, Sr ₅ (PO ₄ ) ₃ Cl: Eu, B
aMgAl ₁₄ O ₂₃ : Eu, BaMg ₂ Al10O17:
Eu, BaMg ₂ Al ₁₄ O ₂₄ : Eu, ZnS: Ag + red pigment, Y ₂ SiO ₃ : Ce, etc. can be used.

(Plasma Display) The front plate and the back plate thus obtained are arranged so that the scanning electrodes on the front plate, the sustain electrodes and the address electrodes on the back plate are arranged orthogonally to enable matrix display driving, and PbO, B ₂ Composite frit composed of O ₃ and ceramic filler, PbO, Zn
After sealing with a glass frit material such as a crystalline frit composed of O and B ₂ O ₃ , the gas is evacuated, a mixed gas of Ne and Xe is sealed, and the scan electrodes scan the drive circuit board via a scan driver IC. The plasma display of the present invention is obtained by connecting to the electrode-side pulse generator, connecting the sustain electrode to the sustain electrode-side pulse generator, and connecting the address electrode to the image processing unit via the data driver IC.

[0029]

The present invention will be specifically described below with reference to examples. However, the present invention is not limited to this.

(Measurement Method, Definition) (1) Symbols Symbols such as electrode widths were defined as follows. The width of the transparent electrode layer of the scanning electrodes: W _T · _SCAN transparent electrode layer of the sustain electrode width: W _T · _SUS scan electrode bus electrode layer of width: W _B · _SCAN sustain electrode bus electrode layer of width: W _B・ Width of the transparent electrode layer of the scanning electrode in the _SUS opening area: W _KT・
The width of the transparent electrode layer of the sustain electrode in the _SCAN opening area: W _KT · _SUS discharge gap: G1 The reverse slit gap: G2 The gap between the scan electrode and the bus electrode layer of the sustain electrode: G3 Here, the reverse slit gap is adjacent It refers to the gap between the transparent electrode layers of the scan electrodes and the sustain electrodes that are not involved in the panel drive discharge.

(2) Line resistance Digital multimeter TR684 manufactured by Advantest Corporation
7 was measured. The scanning electrode was measured between its terminals, and the sustaining electrode was measured for a section having the same length as that between the terminals of the scanning electrode.

(3) Peak value of discharge current Using a current monitor 2877 manufactured by Pearson, voltage level was measured by TDS-744 manufactured by Sony Tektronix, and converted by a converted value V / A = 1.

(4) Luminance The luminance was measured using a color difference meter CS-100 manufactured by Minolta.

(5) Aperture ratio The aperture ratio was determined by the following equation as the ratio of the aperture area per pixel in the width direction of the scanning electrodes and sustain electrodes on the front panel. Opening ratio (%) = G3 × 100 / (G2 + G3 + W B · SCAN
+ W _B · _SUS).

(6) Aperture symmetry As an index for evaluating the symmetry of the emission intensity distribution in the aperture region of one pixel, the aperture symmetry is determined by the following equation. The closer this is to 1, the higher the symmetry. Aperture symmetry = (W _KT · _SCAN + 0.5G1) / (W _KT · _SUS
+ 0.5G1).

(7) Luminous Efficiency Luminous efficiency is a ratio of luminance to power consumed by discharging, and is expressed by the following equation. η = πBS / P Here, η is luminous efficiency, π is pi, B is luminance, S luminous area, and P is discharge power.

Example 1 First, a front plate was manufactured. A transparent electrode layer of ITO having a thickness of 0.4 mm was formed on a 42-inch glass substrate "PD-200" manufactured by Asahi Glass Co., Ltd. by a photo-etching method.
A pattern was formed at 1 μm as follows. _{W T · SCAN = 400μm W T} · SUS = 400μm G1 = 80μm G2 = 200μm.

Next, a bus electrode layer having a thickness of 3 μm was formed in the following pattern by photolithography using a photosensitive silver paste. _{W B · SCAN = 200μm W B} · SUS = 80μm. In each of the scanning electrode and the sustain electrode, the ends of the transparent electrode layer and the bus electrode layer on the opposite side to the opening area in the width direction were aligned. Therefore, the width of the transparent electrode in the opening region was as follows. _{W KT · SCAN = 200μm W KT} · SUS = 320μm.

Next, a transparent dielectric layer was formed to a thickness of 30 μm by screen printing. Further, an MgO protective film is formed to a thickness of 500 nm by an electron beam evaporation method,
A front plate was produced.

Next, a back plate was manufactured. "PD-200" 4
An address electrode pattern was formed on a 2-inch glass substrate by a photolithography method using a photosensitive silver paste. Then, the dielectric layer was screen-printed by 20 μm.
m was formed. Next, a partition was formed by a photolithography method using a photosensitive partition paste. Next, a phosphor layer was formed using a dispenser method. The phosphor powder is
Red: (Y, Gd, Eu) BO3, Green: (Zn, Mn) 2S
iO4, blue: a composition of (Ba, Eu) MgAl10O7 was used. Thus, a back plate was produced.

The front plate and the back plate are aligned so that matrix display driving can be performed, sealed with a glass frit for sealing, evacuated while heating to 350 ° C., and then Xe 5% −
67 kPa of Ne gas was sealed. The scan electrodes are connected to the scan electrode side pulse generator of the drive circuit board via the scan driver IC, the sustain electrodes are connected to the sustain electrode side pulse generator, and the address electrodes are connected to the video processing unit via the data driver IC. Then, a plasma display was produced.

(Example 2) A panel was produced in the same manner as in Example 1 except that the electrodes on the front plate were formed as follows. _{W T · SCAN = 460μm W T} · SUS = 340μm G1 = 80μm G2 = 200μm W B · SCAN = 200μm W B · SUS = 80μm W KT · SCAN = 260μm W KT · SUS = 260μm.

Example 3 The bus electrode layer of the front plate was formed to a thickness of 3 μm using a photosensitive silver paste and a 1 μm film thickness of a photosensitive silver paste containing 5% by weight of ruthenium oxide with respect to silver. A panel was produced in the same manner as in Example 1 except that the panel was composed of two layers.

Comparative Example 1 A panel was manufactured in the same manner as in Example 1 except that the electrodes on the front plate were formed as follows. _{W T · SCAN = 400μm W T} · SUS = 400μm G1 = 80μm G2 = 200μm W B · SCAN = 80μm W B · SUS = 80μm W KT · SCAN = 200μm W KT · SUS = 320μm.

Comparative Example 2 A panel was produced in the same manner as in Example 1 except that the electrodes on the front panel were formed as follows. _{W T · SCAN = 400μm W T} · SUS = 400μm G1 = 80μm G2 = 200μm W B · SCAN = 140μm W B · SUS = 140μm W KT · SCAN = 260μm W KT · SUS = 260μm.

When Examples 1 and 2 are compared with Comparative Examples 1 and 2,
Although the aperture ratio was the same or small, the line resistance of the scanning electrode was low, so that high discharge power was not required and high luminous efficiency could be obtained. In Example 2, higher luminous efficiency could be obtained because of high symmetry of the luminous intensity distribution in the opening region. In Example 3, a product having good contrast was obtained.

[0047]

[Table 1]

[0048]

According to the present invention, by suppressing the voltage drop of the discharge voltage, the load on the driver circuits such as the scan driver IC and the data driver IC can be reduced, and the power consumption, the cost, and the definition can be increased. Also, it is possible to obtain a plasma display with little decrease in luminous efficiency.

[Brief description of the drawings]

FIG. 1 is a plan view of an electrode configuration of a front plate of a plasma display for explaining a first embodiment of the present invention.

FIG. 2 is a plan view of an electrode configuration of a front panel of a plasma display for explaining Embodiment 2 of the present invention.

FIG. 3 is a cross-sectional view of an electrode configuration of a front plate of a plasma display for explaining a third embodiment of the present invention.

FIG. 4 is an exploded perspective view of a conventional plasma display.

FIG. 5 is a sectional view of a conventional plasma display.

FIG. 6 is a plan view of a front plate configuration of a conventional plasma display.

FIG. 7 is a system diagram of a driving circuit of a conventional plasma display.

[Explanation of symbols]

 100: Glass substrate 101: Scan electrode 101B: Bus electrode layer of scan electrode 101T: Transparent electrode layer of scan electrode 102: Sustain electrode 102B: Bus electrode layer of sustain electrode 102T: Transparent electrode layer of sustain electrode 103: Transparent dielectric layer 104: MgO layer 105: front plate 200: glass substrate 201: address electrode 202: dielectric layer 204: phosphor layer 204R: red phosphor layer 204G: green phosphor layer 204B: blue phosphor layer 205: back plate

Claims (6)

[Claims] 1. A plasma display member having a scan electrode and a sustain electrode arranged in parallel with each other, wherein the scan electrode and the sustain electrode have different line resistances. 2. The member for a plasma display according to claim 1, wherein the line resistance of the scan electrode is lower than the line resistance of the sustain electrode. 3. A plasma display member having a scanning electrode and a sustain electrode arranged in parallel with each other, wherein the width of the bus electrode layer of the scanning electrode and the width of the bus electrode layer of the sustain electrode are different. Element. 4. The member for a plasma display according to claim 3, wherein the width of the bus electrode layer of the scan electrode is larger than the width of the bus electrode layer of the sustain electrode. 5. The plasma display according to claim 1, wherein the center of the gap between the scan electrode and the transparent electrode between the sustain electrodes is near the center between the scan electrode and the bus electrode between the sustain electrodes. Parts. 6. A plasma display using the member for a plasma display according to claim 1 as a front plate.