JP2004193141A - Plasma display panel and driving method of the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a plasma display panel comprising a sustaining electrode for the front substrate with low resistance and high transmissivity without using a transparent conductive membrane, having a structure capable of realizing high contrast. <P>SOLUTION: The plasma display panel has a discharge container constructed of a light transmitting front substrate and a rear substrate, and sustaining electrodes 7, 8 arranged on the front substrate. The sustaining electrodes 7, 8 arranged on the front substrate, formed by an opaque conductive membrane, are made of a pair of electrodes respectively constructed of a group of thin electrodes 13 divided in the direction parallel to the long side direction of the sustaining electrodes, and a short circuit part 14 is provided between the thin electrode 13 groups and the short circuit part 14 is constructed so as not to appear in the display cell. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

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

Even if the structure of a plasma display panel (hereinafter, referred to as PDP) is limited to an AC-driven PDP (hereinafter, referred to as ac-PDP), various structures have been conventionally proposed (for example, see Patent Document 1). .).
FIG. 7 is a perspective view showing a conventional plasma display, which has 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 back substrate, barriers called ribs 4 are formed in parallel at a pixel pitch. Between the ribs, a parallel electrode group 5 called a write electrode is provided perpendicular to the sustain electrode, and a phosphor 6 is applied thereon.

  Two pairs of 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 a 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 an MgO film 12 is formed as a dielectric protection layer.

  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. Also, 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. 8, 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 generates a discharge, spreads the discharge, and plays a role of extracting visible light to the outside. The mother electrode plays a role of supplying a current. The mother electrode 10 is usually formed of a low-resistance metal material represented by a three-layer structure such as Cr-Cu-Cr and Cr-Al-Cr, 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.

  9 and 10 show another conventional example regarding the shape of the sustain electrode on the front substrate (see, for example, Patent Document 2). 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.

JP-A-5-307935 (page 4-6, FIG. 2) JP-A-63-56548 (FIGS. 1 and 2)

  In the above-described conventional configuration, 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 a material thereof. 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. Stability and heat resistance are inferior, and there is a drawback that 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 formed mainly 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, but has high conductivity and transparency. Is inferior to the 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.

  Further, since the transparent electrode 9 and the mother electrode 10 have a two-layer structure, it is necessary to accurately align the pattern of the transparent electrode 9 and the pattern of the mother electrode 10, which hinders an improvement in process yield.

  Further, when a mesh pattern as shown in FIGS. 9 and 10 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 currently used driving sequence, the entire surface is discharged once every certain period in order to stably generate the 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.

  The present invention has been made in order to solve the above-described problems, and has a structure in which a front electrode sustain electrode having low resistance and high transmittance is used without using a transparent conductive film, and a high contrast can be obtained. An object of the present invention is to provide a certain plasma display panel and a driving method thereof.

  In the plasma display panel according to the present invention, in a plasma display panel in which a light-transmitting front substrate and a rear substrate form a discharge vessel and sustain electrodes are arranged on the front substrate, the sustain electrodes arranged on the front substrate are opaque. It consists of an electrode pair formed of a conductive film, each of which is composed of a thin electrode group divided in a direction parallel to the long side direction of the sustain electrode, and a short-circuit portion is provided between the thin electrode groups, and in a display cell. The short-circuit portion does not appear.

  Further, in this method of driving a plasma display, priming discharge is caused by using a part of the fine electrode.

  The present invention is configured such that a short-circuit portion does not appear in a display cell, so that a decrease in aperture ratio due to the short-circuit portion does not occur.

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

Embodiment 1 FIG.
In the plasma display panel according to the embodiment of the present invention, the discharge is performed by a fine electrode group formed by a plurality of low-resistance metal electrodes constituting a sustain electrode, and the generated light is extracted by the fine electrode group. It is performed by the gap between them.

  Further, in a sustain electrode whose pattern is weighted so that the width of the narrow electrode near the center of the sustain electrode pair is reduced or the width of the pitch is increased, the narrow gap of the narrow electrode near the center of the sustain electrode pair is more outward. Can extract more light than the slits.

  In addition, 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 back substrate, even if the thin electrode is partially disconnected, 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 occurs using all of the fine electrodes constituting the electrodes of the front substrate, causing light emission, during priming discharge, using a part of the fine electrodes, a discharge smaller than during the sustain discharge, Causes luminescence.

Hereinafter, the present invention will be specifically described 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 a sustain electrode on the front substrate, and the rear substrate may be considered to have a conventional structure as shown in FIG. As shown in the figure, the sustain electrodes 7 and 8 on the front substrate are each provided with 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 number of the sustain electrodes on the front substrate. And a thin electrode group 13 arranged at a pitch of The thin electrode groups 13 constituting one sustain electrode are usually selected so as to have the same potential, but are not necessarily bundled by a pattern. As a material, it is only necessary to give priority to low resistance and compatibility between the lower layer film and the upper layer film in contact with the sustain electrode, and it is not necessary to use a transparent conductive film which 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 there is no electrode, 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 discharge is no different from the conventional discharge constituted by transparent electrodes, 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. The value is almost equal to the area of the electrode to be used.

Embodiment 2 FIG.
Two electrodes are arranged in parallel, and a surface discharge caused by a discharge between the electrodes produces a luminance distribution on the sustain electrodes. This is due to the electric field distribution on the electrode surface, and the region near the center of the sustain electrode pair is bright and darkens outward. 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 thin electrode 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 on the front substrate and the electrodes on the rear substrate of the plasma display panel according to the third embodiment 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. However, this is not always necessary, and a short-circuit portion may be provided at a portion between the fine electrodes.

Embodiment 4 FIG.
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. 4, 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 FIG.
Further, when the sustain electrode has a structure composed of several separated fine electrodes as described in the first, second, third, and fourth embodiments, a driving method for reducing contrast may be employed. it can. FIG. 5 is a schematic diagram showing a method of selecting an electrode and a spread of a discharge during a sustain discharge, and FIG. 6 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, at the time of priming discharge, a part of the fine electrodes 13 of the sustain electrodes 7 and 8 is selected. For example, in the figure, the fine electrode 13 closest to the center of the pair of the sustain electrodes is selected. At this time, the discharge does not spread over the entire sustain electrode, but ends only at the width of the selected narrow 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.

FIG. 2 is a diagram showing electrodes on the front substrate of the plasma display panel according to the first embodiment of the present invention. FIG. 9 is a diagram showing electrodes on a front substrate of a plasma display panel according to Embodiment 2 of the present invention. FIG. 10 is a diagram showing a positional relationship between electrodes on a front substrate and ribs on a rear substrate of the plasma display panel according to Embodiment 3 of the present invention. FIG. 14 is a diagram showing electrodes on a front substrate of a plasma display panel according to Embodiment 4 of the present invention. FIG. 3 is a schematic diagram showing a method of selecting an electrode and a spread of a discharge during a sustain discharge. It is a schematic diagram which shows the selection method of the electrode at the time of priming discharge, and the spread of discharge. It is a perspective view which shows the conventional plasma display. FIG. 9 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. 9 is a view showing electrodes on a front substrate of a conventional plasma display.

Explanation of reference numerals

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

Claims (3)

In a plasma display panel in which a discharge vessel is constituted by a light-transmitting front substrate and a rear substrate, and a sustain electrode is disposed on the front substrate, the sustain electrodes disposed on the front substrate are formed of an opaque conductive film. It consists of an electrode pair composed of a group of fine electrodes divided in a direction parallel to the long side direction of the electrodes, and a short-circuit portion is provided between the fine electrode groups, and the short-circuit portion does not appear in a display cell. A plasma display panel characterized by: In a plasma display panel in which a discharge vessel is formed by a light-transmitting front substrate and a rear substrate, and a sustain electrode is disposed on the front substrate, the sustain electrodes disposed on the front substrate are formed of an opaque conductive film. An electrode pair composed of a group of fine electrodes divided in a direction parallel to the long side direction of the electrodes is provided.A short-circuit portion is provided between the fine electrode groups, and the width of the short-circuit portion is provided on the rear substrate. A plasma display panel having a width smaller than a width of a rib. 3. The method of driving a plasma display panel according to claim 1, wherein a priming discharge is caused by using a part of the fine electrode.

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