JP2004273442A - Plasma display panel and its aging method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a plasma display panel with a long life that can efficiently stabilize a discharge by an aging in a short time. <P>SOLUTION: An aging discharge, generating a discharge trace (a sputter trace) on a protective layer is carried out by impressing a voltage including an alternate voltage component between at least a scanning electrode 5 and a sustaining electrode 6, and the discharge trace on the sustaining electrode 6 side is formed shallower than that on the scanning electrode side, or, out of the discharge traces on the sustaining electrode 6 side, the discharge trace at an area farther away from the scanning electrode 5 pairing as a display electrode is formed shallower than that at an area nearer to the scanning electrode pairing as a display electrode. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

  The present invention relates to an AC type plasma display panel and an aging method thereof.

  2. Description of the Related Art A plasma display panel (hereinafter, abbreviated as PDP or panel) is a display device having excellent visibility, which is characterized by having a large screen, thin shape, and light weight. There are two types of PDP discharge methods: AC type and DC type. Electrode structures include three-electrode surface discharge type and opposed discharge type. However, at present, an AC type and surface discharge type AC type three-electrode PDP is mainly used because it is suitable for high definition and is easy to manufacture.

  In general, an AC type three-electrode PDP is formed by forming a large number of discharge cells between a front substrate and a rear substrate which are arranged to face each other. In the front substrate, a plurality of scan electrodes and sustain electrodes as display electrodes are formed in parallel on a front glass plate, and a dielectric layer and a protective layer are formed so as to cover the display electrodes. The back substrate has a plurality of data electrodes formed on a back glass plate in parallel with each other, and a dielectric layer is formed so as to cover them. A plurality of partitions are formed on the dielectric layer in parallel with the data electrodes, and phosphor layers are formed on the surface of the dielectric layer and on the side surfaces of the partitions. Then, the front substrate and the rear substrate are sealed so as to face each other so that the display electrodes and the data electrodes cross three-dimensionally, and a discharge gas is sealed in a discharge space inside the front substrate and the rear substrate. Thus, the assembly of the panel is completed.

  However, since a newly assembled panel generally has a high discharge starting voltage and an unstable discharge itself, aging is performed in the panel manufacturing process to make the discharge characteristics uniform and stable.

As such an aging method, a method of applying a rectangular wave having an opposite phase as a voltage including an alternating voltage component between display electrodes, that is, between a scanning electrode and a sustaining electrode, for a long time has been adopted. Specifically, a method of applying a rectangular wave to a panel electrode via an inductor to reduce the aging time (see Patent Document 1), or applying a pulse-like voltage having different polarities between a scanning electrode and a sustain electrode. After the surface discharge aging, a method has been proposed in which pulsed voltages having different polarities are continuously applied between the scan electrode, the sustain electrode, and the data electrode to perform a counter discharge (see Patent Document 2).
JP-A-7-226162 JP-A-2002-231141

  It is known that the surface of the protective layer is sputtered by such aging and the film thickness is reduced. However, if spattering is performed more than necessary due to aging more than necessary, there is a problem that the life of the panel is shortened. Was.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a panel having a long life by minimizing aging and a method of aging the panel.

  The plasma display panel according to claim 1, wherein a dielectric layer is formed so as to cover a pair of a scanning electrode and a sustain electrode as a display electrode, and a protective layer is formed on the dielectric layer. Applying a voltage including an alternating voltage component at least between the scan electrode and the sustain electrode to the panel to perform an aging discharge that generates a discharge mark on the protective layer, and discharge the sustain electrode-side discharge mark to the scan electrode side. It is characterized by being formed narrower than the mark. With this configuration, aging can be minimized and a plasma display panel having a long life can be provided.

  The plasma display panel according to claim 2, wherein a dielectric layer is formed so as to cover a pair of a scan electrode and a sustain electrode as a display electrode, and a protective layer is formed on the dielectric layer. With respect to the sustain electrodes, an aging discharge that causes discharge marks on the protective layer is performed by applying a voltage including an alternating voltage component between at least the scan electrodes and the sustain electrodes. The discharge traces in the region far from the scan electrode forming the display electrode are formed shallower than the discharge traces in the region near the scan electrode forming the pair as the display electrode. With this configuration, too, aging of unnecessary regions or spattering of the protective layer due to excessive aging can be minimized, so that a long-life plasma display panel can be provided.

  According to a third aspect of the present invention, in the plasma display panel aging method, a voltage including an alternating voltage component is applied at least between the scan electrode and the sustain electrode to the plasma display panel having the scan electrode, the sustain electrode, and the data electrode. In the aging step of performing aging discharge, at least the rising of the voltage waveform applied to the scan electrode has a gentle slope, or the falling of the voltage waveform applied to the sustain electrode has a gentle slope. . By this aging method, discharge can be efficiently stabilized in a short time, and a plasma display panel having a long life can be obtained.

  ADVANTAGE OF THE INVENTION Since the plasma display panel of this invention and the aging method thereof form small discharge traces during aging, a plasma display panel with a long life can be provided.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment)
FIG. 1 is an exploded perspective view showing the structure of the panel according to the embodiment of the present invention. The panel 1 has a front substrate 2 and a rear substrate 3 which are arranged to face each other. The front substrate 2 has a plurality of pairs of scanning electrodes 5 and sustaining electrodes 6 formed as pairs of display electrodes on the front glass plate 4 in parallel with each other. A dielectric layer 7 is formed so as to cover scan electrode 5 and sustain electrode 6, and a protective layer 8 is formed on dielectric layer 7 so as to cover the surface. Discharge traces described later are formed on the surface of the protective layer 8 by aging. The back substrate 3 has a plurality of data electrodes 10 formed on a back glass plate 9 in parallel with each other, and a dielectric layer 11 formed so as to cover the data electrodes 10. A plurality of partitions 12 are formed on the dielectric layer 11 in parallel with the data electrodes 10, and the phosphor layers 13 are formed on the surface of the dielectric layer 11 and the side surfaces of the partitions 12. Further, a discharge gas is sealed in a discharge space 14 sandwiched between the front substrate 2 and the rear substrate 3.

FIG. 2 is an electrode array diagram of panel 1 according to the embodiment of the present invention. Data electrodes ₁₀ 1 to 10 _m of the m columns (data electrodes 10 in FIG. 1) are arranged in a column direction, (the scanning electrode 5 in FIG. 1) scanning electrodes ₅ 1 to 5 _n n rows in the row direction and n lines and sustain electrodes ₆ 1 to 6 _n (sustain electrodes 6 in Fig. 1) are alternately arranged. Then, m × n discharge cells 18 including a pair of scan electrodes 5 _i , sustain electrodes 6 _i (i = 1 to n) and one data electrode 10 _j (j = 1 to m) are provided in the discharge space. Is formed. Here, the gap to make the scanning electrodes 5 and sustain electrode 6 is referred to as a discharge gap 20 for each discharge cell 18, the gap between the discharge cells, i.e. sustain electrodes belonging to the scan electrode 5 _i and the one made of the discharge cells The gap created by 6i _-1 is called an adjacent gap 21.

  FIG. 3A is a diagram schematically showing discharge traces (sputter traces during aging) observed on the surface of the protective layer after the panel was split after the aging treatment of the panel according to the embodiment of the present invention. Indicates sputter marks. As described above, the discharge trace on the scan electrode 5 side is spread over almost the entire width of the electrode, whereas the discharge trace on the sustain electrode 6 side is a region near the scan electrode 5 forming a pair as a display electrode, that is, the discharge gap 20. It is characterized by being localized in the side region. That is, the discharge trace on the sustain electrode 6 side is formed narrower than the discharge trace on the scan electrode 5 side.

  As described above, the surface of the protective layer 8 is sputtered by aging, but the amount thereof is very small. Therefore, it is generally difficult to observe discharge traces generated by aging with a normal optical microscope. A scanning electron microscope (SEM) that responds sensitively to the surface shape of a substance is suitable for observing these discharge marks. The SEM scans an electron beam on a sample surface to be observed, and observes a secondary electron image emitted from the sample surface. Immediately after film formation, the surface of the MgO film constituting the protective layer has irregularities of about several tens nm to 100 nm. When the surface of the protective layer is sputtered by aging, these minute irregularities become smoother. That is, in the SEM, the amount of secondary electrons coming out of the sample surface is larger on the inclined surface or the projection portion than on the flat portion. Areas not sputtered or weakly sputtered appear bright. Therefore, the discharge trace shown in FIG. 3 can be observed by using SEM. However, since the protective layer 8 is an insulator, it is needless to say that when the SEM observation is performed, the surface needs to be coated with a thin film of platinum or gold to prevent charge-up.

  As shown in FIG. 3, the reason why the discharge traces are formed asymmetrically on the scan electrode 5 side and the sustain electrode 6 side is as follows. In a series of actual discharges of the initialization discharge, the write discharge, the sustain discharge and the three-electrode PDP, the write discharge and the sustain discharge are related to the operating voltage. First, FIG. 3B is a diagram schematically showing discharge traces necessary for reducing and stabilizing a discharge starting voltage in a sustain discharge. In the sustain discharge, a rectangular voltage pulse is applied between the scan electrode 5 and the sustain electrode 6 to generate a discharge. Therefore, a discharge occurs between the two electrodes near the discharge gap 20. Therefore, it is necessary that this part is sufficiently aged, that is, the surface of the protective layer in this part is sufficiently sputtered. Otherwise, due to the sustain discharge when the panel is operated, the surface of the protective layer is sputtered in the same manner as during aging, and the shape change of the surface of the protective layer due to the spatter appears as a change in the sustain discharge voltage, and the display characteristics are reduced. This is because it has an adverse effect. In order to prevent such a state, aging of the scan electrode 5 and the sustain electrode 6 on the side of the discharge gap 20 is mainly promoted, and the discharge gap 20 is formed so that the shape of the surface of the protective layer during the sustain discharge during panel operation hardly changes. It is necessary to make the discharge trace on the side closer to the gap 21 to some extent deeper than the discharge trace on the adjacent gap 21 side. Conversely, it can be said that a stable sustain discharge can be obtained without performing strong aging such that a deep discharge mark is formed in the region on the adjacent gap 21 side.

  On the other hand, FIG. 3C is a diagram schematically showing discharge traces necessary for reducing and stabilizing a discharge starting voltage in a write discharge. Write discharge occurs between the scan electrode 5 and the data electrode 10. Therefore, in order to stabilize the drive voltage at the time of writing without fluctuation during the panel operation, the entire surface of the region on the side of the scanning electrode 5 facing the data electrode 10 is aged, and the entire surface of the scanning electrode 5 is uniformly sputtered. It is desirable to make a mark. In other words, aging (in other words, formation of discharge marks) on the sustain electrode 6 side is not so important as far as writing discharge is concerned.

  Therefore, in order to stabilize both the sustaining and writing discharges, a region satisfying both FIGS. 3B and 3C, that is, a discharge mark shown in FIG. 3A is desirable. Here, the region on the discharge gap 20 side of the scan electrode 5 is involved in both the sustain discharge and the write discharge. However, it is not necessary to form the discharge trace in this region deeper than the discharge trace on the adjacent gap 21 side. May be performed uniformly on the entire surface on the scanning electrode 5 side. Rather, aging the area on the side of the discharge gap 20 more than necessary not only shortens the life of the panel but also increases unnecessary power, which is not desirable.

  FIG. 3D is a diagram schematically illustrating an example of the distribution of the depth of the discharge trace of the panel according to the embodiment of the present invention. The depth of the discharge trace due to the aging discharge does not have a binary distribution as shown in FIG. 3A, but is continuously distributed as shown in FIG. 3D. As described above, of the discharge traces on the sustain electrode 6 side, the discharge traces in the region far from the paired scan electrodes 5 as the display electrodes are formed to be shallower than the discharge traces in the region near the paired scan electrodes 5 as the display electrodes. Have been.

  As described above, by performing the minimum aging in the necessary area, the spatter of the protective layer 8 can be minimized, so that the life of the panel can be extended. In addition, the time required for the aging can be shortened, It can also increase efficiency.

  FIGS. 4A and 4B are diagrams showing an example of an aging waveform for forming an asymmetric discharge trace according to the embodiment of the present invention, in which an alternating voltage component is applied between scan electrode 5 and sustain electrode 6. Is applied. As shown in FIG. 4A, the voltage waveform applied to the scanning electrode 5 has a sharp fall and a gentle slope. Further, the voltage waveform applied to the sustain electrode 6 has a sharp rise and a gentle slope as shown in FIG. 4B. Note that both the rising edge of the voltage waveform applied to the scanning electrode 5 and the falling edge of the voltage waveform applied to the sustain electrode 6 have a gentle slope, but even if either one has a gentle slope. Good. Although the voltage waveform applied to the data electrode 10 is not shown, it may be left open, or may be a ground potential.

  FIG. 4C is a diagram schematically showing a waveform of light emitted from the panel detected by the photosensor in the embodiment of the present invention. As described above, it can be seen that a strong discharge occurs at a steep timing of a voltage change, and a weak discharge occurs at a timing of a gentle voltage change. In this aging waveform, at the timing of strong discharge, the scanning electrode 5 side becomes a cathode, so that positive ions fly and spatter the surface of the protective layer 8 strongly. On the other hand, electrons fly on the sustaining electrode 6 side, but the electrons are light. There is no strong sputtering of the protective layer 8 on the electrode 6 side. The subsequent weak discharge is a discharge localized around the discharge gap 20, and positive ions fly toward the discharge gap 20 side of the sustain electrode 6 to sputter the surface of the protective layer 8. It is considered that this is repeated to form the discharge trace shown in FIG.

  In this manner, a relatively strong discharge is generated at the timing when the scanning electrode 5 falls (becomes a cathode), and a relatively weak discharge is generated at the timing when the sustain electrode 6 falls (becomes a cathode). The discharge marks schematically shown in FIG. 3 can be formed. However, if an excessively strong aging discharge is generated by increasing the voltage applied to the electrodes, the discharge marks on the adjacent gap 21 side are undesirably deeper than the discharge marks on the discharge gap 20 side. In the present embodiment, V = 210 V was obtained experimentally as the optimum voltage. Since this value greatly depends on the electrode structure and material of the panel, it needs to be experimentally optimized each time.

  As described above, in the AC type three-electrode PDP, it is necessary to perform aging for the sustain discharge and the write discharge, which are two main discharge modes. However, by performing the minimum aging, it is shown in FIG. Such ideal discharge marks are formed on the protective layer 8. Conversely, by designing an aging waveform and an aging device so as to form discharge marks as shown in FIG. 3A, a panel with a long life can be provided.

  INDUSTRIAL APPLICABILITY The panel and its aging method of the present invention have a small discharge mark during aging, so that a long-life panel can be provided, and are useful as an AC plasma display panel and its aging method.

Exploded perspective view showing a structure of a panel according to an embodiment of the present invention. Electrode array diagram of panel in embodiment of the present invention (A) is a diagram schematically showing a discharge trace after aging treatment of the panel in the embodiment of the present invention, and (b) is a schematic view showing a discharge trace necessary for reducing and stabilizing a discharge starting voltage in a sustain discharge. FIG. 4C schematically shows discharge traces required to reduce and stabilize the discharge starting voltage in the writing discharge, and FIG. 4D schematically shows an example of the depth distribution of the discharge traces of the panel. Schematic diagram (A) is a diagram showing an example of an aging waveform for forming an asymmetric discharge trace in the embodiment of the present invention; (b) is a diagram showing an example of an aging waveform for forming an asymmetric discharge trace (c). Is a diagram schematically showing the waveform of light emitted from the panel detected by the photo sensor.

Explanation of reference numerals

REFERENCE SIGNS LIST 1 panel 2 front substrate 3 rear substrate 4 front glass plate 5, 5 _{1 to} 5 _n scan electrode 6, 6 _{1 to} 6 _n sustain electrode 7 dielectric layer 8 protective layer 9 back glass plate 10, 10 ₁ to 10 _m data electrode DESCRIPTION OF SYMBOLS 11 Dielectric layer 12 Partition wall 13 Phosphor layer 14 Discharge space 18 Discharge cell 20 Discharge gap 21 Adjacent gap

Claims (3)

A dielectric layer is formed so as to cover a pair of a scan electrode and a sustain electrode as a display electrode, and at least the scan electrode and the sustain electrode are formed on a plasma display panel having a protective layer formed on the dielectric layer. Applying a voltage including an alternating voltage component during the aging discharge to generate a discharge mark on the protective layer,
The discharge trace on the sustain electrode side is formed narrower than the discharge trace on the scan electrode side. A dielectric layer is formed so as to cover a pair of a scan electrode and a sustain electrode as a display electrode, and at least the scan electrode and the sustain electrode are formed on a plasma display panel having a protective layer formed on the dielectric layer. Applying a voltage including an alternating voltage component during the aging discharge to generate a discharge mark on the protective layer,
Of the discharge traces on the sustain electrode side, discharge traces in a region far from the scan electrode forming a pair as the display electrode are formed shallower than discharge traces in a region near the scan electrode forming a pair as the display electrode. A plasma display panel characterized by the following. In the aging step of performing aging discharge by applying a voltage including an alternating voltage component between at least the scan electrode and the sustain electrode to the plasma display panel having the scan electrode, the sustain electrode, and the data electrode,
An aging method for a plasma display panel, wherein at least a rising edge of a voltage waveform applied to the scan electrode has a gentle slope, or a falling edge of a voltage waveform applied to the sustain electrode has a gentle slope.

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