JPH10149774A - Plasma display panel and driving method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a plasma display panel which has a retaining electrode of a front substrate with low resistance and high transmittance and which has a structure for giving high contrast without using a transparent conductive film. SOLUTION: In this plasma display panel of which an electric discharge container is constituted of a light transmissive front substrate and back side substrate and which comprises two or more electrodes in the electric discharge container, retaining electrodes 7, 8 on the front substrate are constituted of a group of thin electrodes 13 comprising two or more thin electrodes 13 which have a width one third, fourth, or so of the retaining electrodes 7, 8 on the front substrate and which are parallel in the longitudinal direction of the retaining electrodes and arranged at prescribed pitches.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a plasma display panel and a driving method thereof.

[0002]

2. Description of the Related Art Plasma display panels (hereinafter referred to as P
The structure of an AC-driven PDP (hereinafter referred to as ac)
-PDP), various proposals have been made in the past. FIG. 7 shows, for example, Japanese Patent Application Laid-Open No. 5-307935.
FIG. 1 is a perspective view showing a conventional plasma display disclosed in Japanese Unexamined Patent Application Publication No. HEI 9-209, having an ac-PDP structure called a surface discharge type. In FIG. 1, reference numeral 1 denotes a front substrate, and 2 denotes a rear substrate. The two substrates are arranged to face each other, and a discharge space 3 is formed therebetween. Several hundred Torr of a mixed gas of a rare gas such as Xe and another rare gas is sealed in the discharge space as a gas generating ultraviolet rays by the discharge.

On the rear substrate, barriers called ribs 4 are formed in parallel at a pixel pitch. Parallel electrode groups 5 called write electrodes are provided between the ribs perpendicularly to the sustain electrodes.
The phosphor 6 is applied thereon.

A pair of two electrodes are formed on the front substrate. The pair of electrodes is called an X electrode 7 and a Y electrode 8, and are arranged in parallel with each other at a pixel pitch and in a direction perpendicular to the writing electrode 5 and the rib 4. Since the X electrode 7 and the Y electrode 8 are mainly used as electrodes for maintaining display, they are referred to herein as sustain electrodes, and the X electrode and the Y electrode are collectively referred to as a sustain electrode pair. A dielectric layer 11 is formed on these electrodes, and MgO is used as a dielectric protection layer.
A film 12 is formed.

Next, the principle of light emission will be described. When a potential difference is generated between the sustain electrodes of the front substrate and a discharge occurs, the phosphor 6 is excited by ultraviolet rays generated by the discharge to generate visible light. The generated visible light is extracted to the outside through the front substrate 1. Since the reflected light of the phosphor is viewed from the display surface, it is generally called a reflection type. Further, the discharge occurs on the sustain electrode close to the sustain electrode pair, and moves toward the outside of the electrode with time. For this reason, a certain amount of electrode area is required in order to generate ultraviolet rays sufficiently by discharge.

As described above, in the reflection type PDP, the sustain electrode supplies a current to generate a discharge, and has a role of spreading the discharge and a role of extracting visible light generated by the phosphor to the outside. However, a material that sufficiently satisfies both low resistance and high transmittance has not been found as a sustain electrode material. In the conventional PDP, as shown in FIG. 7, the sustain electrodes 7 and 8 are composed of two layers of a transparent electrode 9 and a mother electrode 10. Here, the transparent electrode 9 causes a discharge, spreads the discharge, and plays a role of extracting visible light to the outside, and the mother electrode plays a role of supplying a current. The mother electrode 10 is usually made of Cr-Cu-Cr, Cr-Al-
A low-resistance metal material represented by a three-layer structure such as Cr is used, and is formed by a thin film process. In addition, it may be formed by a thick film printing process using a printing paste such as gold or silver. In general, the mother electrode 10 is disposed on the transparent electrode 9 as far as possible from the center of the sustain electrode pair in order to increase the light extraction efficiency.

FIGS. 8 and 9 show another conventional example of the shape of the sustain electrode on the front substrate disclosed in Japanese Utility Model Application Laid-Open No. 63-56548. In this conventional example, a transparent metal electrode is not used as the electrode of the front substrate, but is formed of a mesh-like metal thin film.

[0008]

In the above-mentioned conventional structure, the transparent electrodes 9 are formed on the sustain electrodes 7 and 8, and an oxide film such as ITO and SnO2 is generally used as the material. ITO is mainly formed by a physical vapor deposition method such as a vacuum vapor deposition method, a sputtering method, or an ion plating method, and is superior in conductivity, transparency, and ease of patterning processing to a SnO2 film, but is chemically resistant. It has poor stability and heat resistance, and it is difficult to cope with large area and mass production due to the physical vapor deposition method. On the other hand, since the SnO2 film is mainly formed by a chemical vapor deposition method (CVD method), it is easy to cope with a large area and mass production, and is excellent in chemical stability and heat resistance. Is inferior to an ITO film and has a drawback that it is difficult to perform high-precision patterning because of its excellent chemical stability. Either way, there are advantages and disadvantages, and using a transparent conductive film of an oxide such as ITO or SnO2 as an electrode is not the best choice in terms of PDP performance in terms of process.

Also, since the transparent electrode 9 and the mother electrode 10 have a two-layer structure, the pattern of the transparent electrode 9 and the mother electrode 1
It is necessary to accurately align the pattern of 0, which hinders the improvement of the process yield.

Further, when a mesh-like pattern as shown in FIGS. 7 and 8 is used, it is impossible to achieve both a high aperture ratio and a low resistance. The mesh-like pattern is formed by a component in the long side direction and a component in the short side direction, but the component in the short side direction is not effective for lowering the resistance and lowers the aperture ratio.

In the drive sequence currently used, a full discharge is performed once every certain period in order to stably generate a discharge. This is called a priming discharge, and light emission due to the priming discharge needs to be suppressed as much as possible for a contrast ratio. However, since the sustaining discharge for display and the priming discharge are performed between the same sustaining electrodes, only the light emission of the priming discharge cannot be structurally reduced.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and has a front electrode sustaining electrode having a low resistance and a high transmittance without using a transparent conductive film, thereby enabling high contrast. It is an object to provide a plasma display panel having a simple structure and a driving method thereof.

[0013]

In the plasma display panel according to the present invention, the electrodes arranged on the front substrate are parallel to the long side direction and have a width which is a fraction of the number of the electrodes on the two or more front substrates. Of the thin electrode group.

Further, the aperture ratio determined by the electrode width and the pitch of the thin electrodes having a width several times smaller than that of the electrodes of the front substrate constituting the electrodes of the front substrate is high in a region near the center of the electrode pair, and is large. The pattern of the thin electrodes is weighted so as to be low in the region where the color is reduced.

In addition, a short-circuit portion is provided at a part of a narrow electrode group having a width which is a fraction of the number of the electrodes of the front substrate constituting the electrodes of the front substrate at the same interval as the pitch of the ribs of the rear substrate. is there.

Further, fine electrodes having a width which is several times smaller than the electrodes of the front substrate constituting the electrodes of the front substrate are formed at equal pitches on the entire surface of the panel.

Further, as a driving method of the plasma display, a priming discharge is generated by using a thin electrode having a width which is a fraction of the width of the electrode of the front substrate constituting the electrode of the front substrate, and a part of the thin electrode. Things.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In a plasma display panel according to an embodiment of the present invention, discharge is performed by a thin electrode group formed by a plurality of low resistance metal electrodes constituting a sustain electrode, and the generated light is taken out. Is performed by a gap between the thin electrode groups.

In a sustain electrode whose pattern is weighted so as to make the width of the narrow electrode near the center of the sustain electrode pair narrow or to increase the width of the pitch, the narrow gap of the thin electrode near the center of the sustain electrode pair is larger. More light can be extracted than the outer slit.

Further, if a short-circuit portion is provided at a part between the fine electrode groups at the same interval as the pitch of the ribs on the rear substrate, even if the fine electrode is partially broken, the short-circuit portion compensates.

Further, when the fine electrodes are formed at the same pitch on the entire panel, the electrodes can be freely selected after the panel is completed.

Further, when performing the sustain discharge, discharge and light emission are caused by using all of the fine electrodes constituting the electrodes of the front substrate. Causes small discharge and luminescence.

Hereinafter, the present invention will be described in detail with reference to the drawings showing the embodiments. Embodiment 1 FIG. FIG. 1 is a diagram showing electrodes on a front substrate of a plasma display panel according to Embodiment 1 of the present invention. The present invention relates to the sustain electrodes on the front substrate, and the rear substrate may be considered to have a conventional structure as shown in FIG. As shown in the drawing, the sustain electrodes 7 and 8 on the front substrate each have at least two thin electrodes 13 parallel to the long side direction of the sustain electrodes and having a width that is a fraction of the width of the sustain electrodes on the front substrate. And a group of fine electrodes 13 arranged at a pitch of The thin electrode groups 13 forming one sustain electrode are usually selected to have the same potential, but are not necessarily bundled by a pattern. As a material, priority should be given to low resistance and compatibility between the lower layer film and the upper layer film that are in contact with the sustain electrode, and it is not necessary to use a transparent conductive film that is difficult to handle in a process. Regarding the relationship between the resistance and the aperture ratio, since there is no short-side component pattern that hardly contributes to the reduction in resistance on the display surface, both low resistance and high aperture ratio can be achieved.

When a potential equal to or higher than the discharge start voltage is applied between the X electrode 7 and the Y electrode 8, the discharge starts in a region near the center of the sustain electrode pair, and the discharge spreads outward. At this time, it appears that no potential is applied to a portion of the sustain electrode where no electrode is provided, but the sustain electrode is covered with a dielectric, and the potential spreads over the narrow electrode width 13 on the dielectric. Therefore, the discharge started near the gap does not end at the portion where the electrode is interrupted, but spreads to the outside. The form of the discharge is no different from the conventional discharge constituted by the transparent electrode, and the effective electrode area of the dielectric surface is determined by the thin electrode 13 closest to the center of the sustain electrode pair and the outermost thin electrode. This value is almost equal to the area of the electrode to be used.

Embodiment 2.2 Two electrodes are arranged in parallel, and in a surface discharge caused by a discharge between the electrodes, a luminance distribution is formed on the sustain electrodes. It is due to the electric field distribution on the electrode surface, and the area near the center of the sustain electrode pair is bright,
Darkens outwards. FIG. 2 is a diagram showing electrodes on the front substrate of the plasma display panel according to the second embodiment of the present invention. As shown in FIG. Light extraction efficiency can be improved by weighting the pattern of the width and pitch of the fine electrodes 13 so as to be higher than the aperture ratio of the region outside the low electrode.

Embodiment 3 FIG. The fine electrode widths in the first and second embodiments need to be determined with sufficient consideration so as not to cause disconnection in the middle, but it cannot be denied that there is a possibility of disconnection in the process. FIG. 3 is a diagram showing the positional relationship between the electrodes of the front substrate and the ribs of the electrodes of the rear substrate of the plasma display panel according to Embodiment 3 of the present invention. As shown in FIG. The short-circuit part 14 is provided in the side direction. Thereby, even if a part of the fine electrode 13 is disconnected, it can be compensated at the short-circuit portion. In addition, the pitch of the short-circuit portion in the long side direction is matched with the pitch of the rear substrate so that the short-circuit portion, which is a component in the short side direction, does not appear in the display cell. Therefore, the aperture ratio does not decrease due to the short-circuit portion. In the figure, the short-circuit portion is provided between all the fine electrodes, but it is not always necessary to do so, and a short-circuit portion may be provided at a portion between the fine electrodes.

Embodiment 4 In the first and second embodiments, the widths of the sustain electrodes 7 and 8, the gap between the sustain electrodes, and the pitch of the pair of sustain electrodes are determined at the design stage, and cannot be changed after the panel is completed. . In FIG. 3, fine electrodes 13 having a width that is several times smaller than the electrodes of the front substrate are formed at equal pitches over the entire panel. Thus, even after the panel is completed, the width of the sustain electrodes 7 and 8, the gap between the sustain electrodes, and the pitch of the pair of sustain electrodes can be freely changed by changing the way of selecting the electrodes. That is, it is possible to change the specifications of the panel according to the user's request while using the same panel.

Embodiment 5 In the first embodiment,
When the sustain electrode has a structure composed of several separated fine electrodes as shown in 2, 3, and 4, a driving method for reducing contrast can be adopted. FIG. 4 is a schematic diagram showing a method of selecting an electrode and a spread of a discharge during a sustain discharge, and FIG. 5 is a schematic diagram showing a method of selecting an electrode and a spread of a discharge during a priming discharge. At the time of the sustain discharge, all the fine electrodes 13 corresponding to the sustain electrodes 7 and 8 are selected so as to select the normal electrode. At this time, the discharge spreads over the entire sustain electrode, and light emission sufficient for display is obtained. On the other hand, during the priming discharge, the sustain electrodes 7, 8
Are selected, and for example, in the figure, the thin electrode 13 closest to the center of the sustain electrode pair is selected. At this time, the discharge does not spread over the entire sustain electrode, but ends only at the width of the selected thin electrode 13, and the light emission due to the discharge is considerably lower than the light emission due to the sustain discharge. Therefore, the contrast ratio is improved.

[0029]

Since the present invention is configured as described above, it has the following effects.

Since the electrodes arranged on the front substrate are composed of a group of two or more narrow electrodes parallel to the long side direction and having a width that is a fraction of the number of the electrodes of the front substrate, transparent electrodes are used. As a result, the process can be shortened and simplified.

Further, since there is no component in the short side direction of the sustain electrode which is not effective in reducing the resistance, an electrode having a low resistance and a high aperture ratio can be realized.

The pattern is weighted such that the electrode width and the pitch of the fine electrodes constituting the electrodes of the front substrate are high in the area near the center of the electrode pair and low in the area far from the center. By doing so, the light extraction efficiency can be increased.

Further, if a short-circuit portion is provided in a part between the thin electrode groups at the same interval as the pitch of the ribs on the rear substrate, even if the thin electrode is partially disconnected, the short-circuit portion compensates for the short-circuit portion, and the yield is increased. Is improved.

In addition, by forming the front narrow electrodes constituting the electrodes of the front substrate at the same pitch on the entire surface of the panel, the specifications such as the width of the sustain electrodes, the gap between the sustain electrodes, and the pitch of the sustain electrodes can be maintained even after the panel is completed. It can be easily changed, and the degree of freedom in design can be increased.

Further, by generating a priming discharge by using a part of the fine electrodes constituting the electrodes of the front substrate, the light emission by the priming discharge can be made smaller than the light emission by the sustain discharge used for display, and the contrast ratio can be reduced. Can be improved.

[Brief description of the drawings]

FIG. 1 is a diagram showing electrodes on a front substrate of a plasma display panel according to a first embodiment of the present invention.

FIG. 2 is a diagram showing electrodes on a front substrate of a plasma display panel according to Embodiment 2 of the present invention;

FIG. 3 is a diagram showing a positional relationship between electrodes on a front substrate and ribs on a rear substrate of a plasma display panel according to Embodiment 3 of the present invention.

FIG. 4 is a schematic diagram showing a method of selecting an electrode and a spread of a discharge during a sustain discharge.

FIG. 5 is a schematic diagram showing a method of selecting electrodes during priming discharge and the spread of discharge.

FIG. 6 is a schematic diagram showing a method of selecting a sustain electrode and a spread of discharge during priming discharge of a plasma display panel according to Embodiment 4 of the present invention.

FIG. 7 is a perspective view showing a conventional plasma display.

FIG. 8 is a view showing electrodes on a front substrate of a conventional plasma display.

FIG. 9 is a view showing electrodes on a front substrate of a conventional plasma display.

FIG. 10 is a diagram showing electrodes on a front substrate of a conventional plasma display.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 front substrate, 2 back substrate, 3 discharge space, 4 ribs, 5 writing electrode, 6 phosphor, 7 sustain electrode (X electrode), 8 sustain electrode (Y electrode), 9 transparent electrode, 10
Mother electrode, 11 dielectric layer, 12 MgO film, 13 fine electrode, 14 short circuit part.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Tatsuya Yamamoto 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsubishi Electric Corporation

Claims (5)

[Claims] 1. A discharge container is constituted by a light-transmitting front substrate and a rear substrate, and at least two or more electrodes are provided in the discharge container, and among these electrodes, an electrode arranged on the front substrate has a long side. A plasma display panel comprising a thin electrode group having a width that is a fraction of the number of electrodes of the two or more front substrates parallel to a direction. 2. An aperture ratio determined by an electrode width and a pitch of a thin electrode having a width of a fraction of the number of electrodes of the front substrate constituting the electrodes of the front substrate is high in a region near the center of the electrode pair and is large. 2. The plasma display panel according to claim 1, wherein the pattern of the fine electrodes is weighted so as to be lower in a region where the plasma is generated. 3. A short-circuit portion is provided at a part of a narrow electrode group having a width which is a fraction of the number of the electrodes of the front substrate constituting the electrodes of the front substrate at the same interval as the pitch of the ribs of the rear substrate. 3. The plasma display panel according to claim 1, wherein: 4. The plasma display according to claim 1, wherein fine electrodes having a width of a fraction of the width of the electrodes of the front substrate constituting the electrodes of the front substrate are formed at an equal pitch over the entire surface of the panel. panel. 5. A priming discharge is generated by using a part of a thin electrode having a width which is a fraction of the number of electrodes of the front substrate constituting the electrode of the front substrate. The method for driving a plasma display panel according to any one of the above.