JP2003217455A - Plasma display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a plasma display device having improved emission efficiency and higher picture quality, capable of being precisely manufactured in higher yields. <P>SOLUTION: The plasma display device comprises a pair of boards on front and back sides opposed to each other so that a discharge space partitioned with barrier ribs is formed between the boards, a plurality of display electrodes consisting of scanning electrodes 4 and maintaining electrodes 5 arrayed on the board 3 on the side of a front panel 1 so that discharge cells are formed between the barrier ribs, a dielectric layer 17 formed on the board 3 on the front side so that the display electrodes 6 are covered, and a fluorescent layer for emitting a light with electric discharge between the display electrodes. A cylindrical, conical, elliptically columnar or elliptically pyramidal recess 18 existing in each of the discharge cells is formed in the surface of the dielectric layer 17 on the side of the discharge space. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display device known as a display device.

[0002]

2. Description of the Related Art In recent years, expectations for large screens and wall-mounted televisions as interactive information terminals are increasing. As display devices therefor, there are many liquid crystal display panels, field emission displays, electroluminescence displays, and the like, some of which are commercially available and some of which are under development. Among these display devices, plasma display panel (hereinafter referred to as PDP)
Is a self-luminous type that can display beautiful images, and it is easy to increase the screen size.
It has attracted attention as a thin display device with excellent visibility, and high definition and large screen are being promoted.

This PDP is roughly classified into A drive type.
There are C type and DC type, and there are two types of discharge type, a surface discharge type and a counter discharge type, but at present, due to high definition, large screen and ease of manufacturing, AC type and surface discharge type PDPs are currently available. Are becoming mainstream.

FIG. 6 shows an example of a panel structure of the PDP. As shown in FIG. 6, the PDP is composed of a front panel 1 and a rear panel 2.

The front panel 1 is a striped display electrode in which a scan electrode 4 and a sustain electrode 5 are paired on a transparent front substrate 3 such as a glass substrate made of sodium borosilicate glass by the float method. 6 are arranged in a plurality of pairs, a dielectric layer 7 is formed so as to cover the display electrode 6 group, and a protective film 8 made of MgO is formed on the dielectric layer 7. . The scanning electrode 4
And sustain electrode 5 are transparent electrodes 4a, 5a and Cr / electrically connected to transparent electrodes 4a, 5a, respectively.
The bus electrodes 4b and 5b are made of Cu / Cr or Ag. Although not shown, a plurality of black stripes serving as a light shielding film are formed between the display electrodes 6 in parallel with the display electrodes 6.

In the rear panel 2, the address electrodes 10 are formed in a direction orthogonal to the display electrodes 6 on the rear substrate 9 arranged so as to face the front substrate 3.
A dielectric layer 11 is formed so as to cover the address electrodes 10, and a plurality of stripe-shaped partition walls 12 are formed on the dielectric layer 11 between the address electrodes 10 in parallel with the address electrodes 10 and between the partition walls 12. It is configured by forming a phosphor layer 13 on the side surface of and the surface of the dielectric layer 11. The phosphor layer 1 is used for color display.
In general, three colors of red, green, and blue are normally arranged in order.

The front panel 1 and the rear panel 2 are arranged such that the substrates 3 and 9 face each other with a minute discharge space sandwiched therebetween so that the display electrodes 6 and the address electrodes 10 are orthogonal to each other, and A panel is constructed by sealing with a sealing member, and then filling a discharge gas, which is a mixture of neon and xenon, in the discharge space at a pressure of about 66500 Pa (500 Torr).

The discharge space of this panel is partitioned into a plurality of partitions by partition walls 12, and the display electrodes 6 are provided so that a plurality of discharge cells to be light emitting pixel regions are formed between the partition walls 12. The display electrodes 6 and the address electrodes 10 are arranged orthogonal to each other.

That is, as shown in FIG.
The display electrodes 6 are formed by arranging the sustain electrodes 5 and the sustain electrodes 5 with the discharge gap 14 in between, and the region surrounded by the display electrodes 6 and the barrier ribs 12 becomes the light emitting pixel region 15, and the display electrodes of the adjacent discharge cells. A non-light emitting area 16 is provided between the areas 6.

In this PDP, a discharge is generated by a periodic voltage applied to the address electrodes and the display electrodes, and ultraviolet rays generated by the discharge are irradiated to the phosphor layer to convert it into visible light, thereby displaying an image. Be seen.

[0011]

In order to develop the PDP, it is indispensable to further increase the brightness, increase the efficiency, reduce the power consumption, and reduce the cost. In order to achieve high efficiency, it is necessary to control the discharge and suppress the discharge in the shielded area as much as possible. As one of the methods for improving the efficiency, there is known a method of increasing the film thickness of the dielectric layer on the bus electrode of the display electrode so as to suppress the light emission of the portion shielded by the bus electrode.

However, in the above-mentioned conventional structure, since the thickened portion of the dielectric layer is only on the bus electrode, the discharge spreads in the direction parallel to the bus electrode, and even near the partition wall where the electron temperature decreases. Discharge reaches and efficiency decreases. Further, since the partition wall of the rear substrate and the thickened portion of the dielectric layer of the front panel are in contact with each other to form a gap, erroneous discharge may occur in the direction parallel to the electrodes, and the image quality may be deteriorated.

Further, in the prior art, since the discharge is concentrated in the discharge gap, luminance saturation of the phosphors in the vicinity thereof is likely to occur and the efficiency is lowered.

In order to improve the efficiency of such a PDP,
As shown in FIG. 7, the non-emission region 16 between adjacent discharge cells
Is narrowed and the display electrode 6 on the side of the discharge gap 14 is widened to widen the spread of discharge. In this case, however, erroneous discharge with adjacent cells is increased. It has been difficult to achieve both the narrowing of 16 and the widening of the display electrode 6 to widen the spread of discharge.

Further, in the case of forming a recess in the dielectric to solve the above problems, if the shape of the recess is a cube or a rectangular parallelepiped, stress concentrates on the square during firing of the dielectric, and the shape is deformed. However, there is a problem that the accuracy cannot be maintained.

The present invention has been made to solve the above problems, and an object of the present invention is to improve the luminous efficiency and the image quality, and to enable the manufacturing with high yield and high accuracy.

[0017]

In order to achieve this object, the present invention is to provide a columnar shape, a conical shape, an elliptic column shape or an elliptic cone on the surface of the dielectric layer on the side of the discharge space for each discharge cell. It is formed with a concave portion.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS That is, the invention according to claim 1 of the present invention comprises a pair of front side and rear side substrates which are arranged so as to face each other so that a discharge space partitioned by a partition wall is formed between the substrates. A plurality of display electrodes arranged on the front substrate so that discharge cells are formed between the barrier ribs, a dielectric layer formed on the front substrate so as to cover the display electrodes, A phosphor layer that emits light by discharge between the display electrodes, and on the surface of the dielectric layer on the side of the discharge space, a columnar shape, a conical shape, an elliptic column shape, or an elliptical cone shape for each of the discharge cells. It is characterized in that a concave portion is formed.

Further, according to a second aspect of the present invention, a pair of front side and back side substrates are disposed so as to face each other so that a discharge space partitioned by the barrier ribs is formed between the substrates, and a discharge cell is provided between the barrier ribs. A plurality of display electrodes formed on the front side substrate so as to form a dielectric layer formed on the front side substrate so as to cover the display electrodes, and a discharge between the display electrodes. It has a phosphor layer which emits light, and a polygonal columnar or polygonal pyramid-shaped recess is formed in each discharge cell on the surface of the dielectric layer on the side of the discharge space.

Further, according to a third aspect of the present invention, a pair of front side and rear side substrates are disposed so as to face each other so that a discharge space partitioned by the barrier ribs is formed between the substrates, and a discharge cell is provided between the barrier ribs. A plurality of display electrodes formed on the front side substrate so as to form a dielectric layer formed on the front side substrate so as to cover the display electrodes, and a discharge between the display electrodes. A fluorescent layer that emits light, and a quadrangular prism-shaped or quadrangular pyramid-shaped recess is formed for each discharge cell on the surface of the dielectric layer on the side of the discharge space, and the square of the recess has a curved surface. It is characterized in that it is formed.

A plasma display device according to an embodiment of the present invention will be described below with reference to the drawings of FIGS. 1 to 5, the same parts as those shown in FIG. 6 are designated by the same reference numerals and the description thereof will be omitted.

1 to 3 show the structure of the discharge cell portion in the panel of the plasma display device according to one embodiment of the present invention. In the figure, reference numeral 17 is a dielectric layer formed on the front substrate 3 so as to cover the display electrodes 6. The surface of the dielectric layer 17 on the discharge space side has recesses 18 to 20 for each discharge cell. Are formed.

That is, in the embodiment shown in FIG. 1, a cylindrical recess 18 is formed, and in the embodiment shown in FIG. 2, an octagonal polygonal recess 19 is formed. Further, in the embodiment shown in FIG. 3, the shape is a square pole, and R is formed so that the square of the recess 20 has the curved surface 20a.

As described above, in the case of forming a recess in the dielectric layer, if the shape of the recess is a cube or a rectangular parallelepiped, stress is concentrated on the square during firing of the dielectric, resulting in deformation of the shape or accuracy. Although a problem that cannot be maintained occurs, in the present invention, a cylindrical concave portion 18, a polygonal concave portion 19 such as an octagon, or a quadrangular prism-shaped curved surface 20a.
Since the concave portion 20 having the shape is formed, stress is not concentrated on the square when the dielectric is fired, and the shape is not deformed.

As the shape of the concave portion applicable to the present invention, in addition to the above, the conical shape, the elliptic cylindrical shape, the elliptic cone shape, the polygonal pyramid shape, or the quadrangular pyramid shape forms a square curved surface. It is possible to use the one having the above shape.

By the way, in order to achieve high efficiency of the PDP, it is essential to control the discharge in each light emitting pixel region. In particular, when the discharge spreads in the direction perpendicular to the display electrodes, the bus electrode blocks the emitted light from the phosphor layer, so it is necessary to suppress the spread of the discharge to the shielded portion. Further, since the partition wall does not exist in this direction, all the ultraviolet rays leaking from the partition wall and the light emission from the phosphor layer are shielded by the black stripe.
Further, it is known that the spread of the discharge in the direction parallel to the display electrodes causes a decrease in efficiency due to a decrease in electron temperature near the partition.

Further, it is considered that the discharge spreads in a circular shape from the center of the discharge gap, and most ideally, the shape of the bottom surface of the recess for generating the discharge is a circle or an ellipse. Furthermore, when forming a recess in the dielectric, the wall surface can be made smooth to form a protective layer on the surface. Therefore, a decrease in electron temperature as in the partition wall and recombination of ions and electrons do not essentially occur, so that loss of efficiency can be prevented.

In the present invention, the concave portion 18 is formed on the surface of the dielectric layer 17 on the discharge space side for each discharge cell forming the light emitting pixel region. As shown in FIG.
Since the capacitance of the bottom surface of the concave portion 18 having the thinner dielectric layer 17 is increased, the electric charges for discharge are concentrated on the bottom surface of the concave portion 18, and the discharge is performed as shown in A of FIG. You can limit the area. On the other hand, in FIG. 5 having a structure without a recess, since the film thickness of the dielectric layer 17 is constant, the capacitance is constant on the surface of the dielectric layer, and as shown in FIG. It spreads out in the vicinity and causes the phosphor in the shielded part to emit light, resulting in reduced efficiency. Further, since electric charges are formed up to a portion close to the adjacent cell, erroneous discharge with the adjacent cell is likely to occur.

As another method of improving efficiency, there is a method of increasing the extraction efficiency of light emitted from the phosphor, that is, increasing the aperture ratio. In this case, it is necessary to separate the bus electrode from the light emitting region as much as possible. However, since the distance between the electrodes of the adjacent cells running in parallel becomes narrower, the electric charge easily moves, and an erroneous discharge occurs in which cells that do not want to emit light emit light, resulting in a problem that display quality is significantly deteriorated. In the present invention, it can be prevented by controlling the position where the wall charge is generated by adjusting the shape of the recess.

[0030]

As described above, according to the plasma display device of the present invention, the dielectric is cylindrical or conical,
Alternatively, the discharge is controlled by forming an elliptic column or an elliptical cone, a polygonal column or a polygonal pyramid-shaped recess, or a square column or a square pyramid-shaped recess, and forming the square with R. It is possible to improve the efficiency and the image quality, and it is possible to stably manufacture the above-described shape with high yield and high accuracy.

[Brief description of drawings]

FIG. 1 is a perspective view showing a structure of a discharge cell portion in a panel of a plasma display device according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a structure of a discharge cell portion of a panel of a plasma display device according to another embodiment of the present invention.

FIG. 3 is a perspective view showing a structure of a discharge cell portion of a panel of a plasma display device according to another embodiment of the present invention.

FIG. 4 is a schematic configuration diagram for explaining effects of the plasma display device.

FIG. 5 is a schematic configuration diagram for explaining a discharge situation of the plasma display device.

FIG. 6 is a perspective view showing a panel structure of a general plasma display device.

FIG. 7 is a plan view showing a configuration of a discharge cell portion of the plasma display device.

[Explanation of symbols]

1 Front panel 2 Rear panel 3, 9 substrate 4 scanning electrodes 5 sustaining electrodes 6 display electrodes 10 address electrodes 12 partitions 13 Phosphor layer 17 Dielectric layer 18, 19, 20 recess 20a curved surface

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Junichi Hibino             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd. F term (reference) 5C040 FA01 FA04 GB03 GB14 GD01                       MA12

Claims (3)

[Claims] 1. A pair of front-side and back-side substrates that are arranged to face each other so as to form a discharge space partitioned by barrier ribs between the substrates, and the front side so that discharge cells are formed between the barrier ribs. A plurality of display electrodes arranged on the substrate, a dielectric layer formed on the front substrate so as to cover the display electrodes, and a phosphor layer that emits light by a discharge between the display electrodes. A plasma display device, characterized in that a columnar shape, a conical shape, an elliptic column shape, or an elliptical cone shape concave portion is formed for each discharge cell on the surface of the dielectric layer on the side of the discharge space. 2. A pair of front-side and rear-side substrates that are arranged so as to face each other so that a discharge space partitioned by the barrier ribs is formed between the substrates, and the front side so that discharge cells are formed between the barrier ribs. A plurality of display electrodes arranged on the substrate, a dielectric layer formed on the front substrate so as to cover the display electrodes, and a phosphor layer that emits light by a discharge between the display electrodes. A plasma display device, characterized in that a polygonal prism-shaped or a polygonal pyramid-shaped recess is formed for each discharge cell on the surface of the dielectric layer on the discharge space side. 3. A pair of front side and back side substrates which are arranged to face each other so as to form a discharge space partitioned by the barrier ribs between the substrates, and the front side so that discharge cells are formed between the barrier ribs. A plurality of display electrodes arranged on the substrate, a dielectric layer formed on the front substrate so as to cover the display electrodes, and a phosphor layer that emits light by a discharge between the display electrodes. A plasma characterized in that a quadrangular prism-shaped or quadrangular pyramid-shaped recess is formed for each discharge cell on the surface of the dielectric layer on the side of the discharge space, and the quadrangle of the recess has a curved surface. Display device.