KR19980075089A - Front electrode of flat panel display device - Google Patents

Abstract

The present invention discloses an improved front electrode of a flat panel display device.

In order to solve the problem that the conventional transparent electrode is difficult to form and has low characteristics and functions, in the present invention, a metal electrode is formed by repetition of a node portion and a branch portion where a plurality of branch electrodes are branched therefrom, and the branch electrodes are formed. A transparent electrode was formed in the window.

Accordingly, the front electrode can be easily formed, there is no deterioration in characteristics, and the transparent electrode can function entirely.

Description

Front electrode of flat panel display device

The present invention relates to a flat panel display device, and more particularly to a front electrode.

Except for some elements of a segment method for displaying a preset image, most flat panel display elements are configured in a dot matrix manner to display a raster image.

In the dot matrix device, as shown in FIG. 1, the electrodes G1 and G2 are arranged opposite to each other on the two substrates P1 and P2 to drive the pixels at the intersection points by selecting the two electrodes G1 and G2. Done. The remaining code B is a partition wall for partitioning between pixels.

The device is divided into front and rear surfaces according to a user's viewing direction. The electrode G1 formed on the front substrate P1, that is, the front electrode is positioned on a light transmission path to the user, thereby inhibiting overtransmission. There is a problem of lowering.

Accordingly, it is common to form the front electrode G1 as the transparent electrode T by using a transparent conductive material such as indium tin oxide (ITO).

However, there is no problem in the device having low driving voltage and power such as LCD, but in the high voltage high power device such as PDP, the voltage drop is severe with the transparent electrode T of low conductivity, which makes it difficult to drive the device uniformly.

Accordingly, the stacked front electrode G1 having a structure in which the metal electrode M of the smaller transparent electrode is stacked as a bus electrode on the transparent electrode T is widely used.

However, since the metal electrode M is opaque, light transmission is inhibited. In the related art, the projection area of the metal electrode M is reduced as much as possible, or as shown in FIG. 2, the metal electrode M is moved toward one side of the pixel. Adopted the arrangement to arrange.

However, this configuration prevents the two electrodes G1 and G2 from intersecting at the center of the pixel so that the pixel cannot be used for image display on the entire surface. In particular, in the case of the PDP, the luminous intensity decreases.

Another problem with the use of the transparent electrode T is that ITO is difficult to print on the glass substrate P1. In other words, ITO has low adhesion to the substrate P1, so that the straightness of printing is poor and the edges thereof are not uniform, so that pattern printing is impossible.

Accordingly, although the metal electrode M on the transparent electrode T or the electrode G2 of the opposite substrate P2 can be formed by a simple and inexpensive thick film method such as printing, the transparent electrode T is an expensive and complicated thin film. It could be manufactured by a process, mainly photo lithography.

The transparent electrode T is also vulnerable to heat, so that the conductive property of the metal electrode M is further reduced.

However, a larger problem of the conventional stacking front electrode G1 illustrated in FIGS. 1 and 2 is that the large-area transparent electrode T hardly plays a role.

In other words, the current flows through the path of the least resistance, and the current applied to the metal electrode M, which is the bus electrode, flows mainly along the metal electrode M, but hardly diffuses to the transparent electrode T stacked thereon. In the image display, the metal electrode M mainly functions, and the role of the transparent electrode T is very small. In particular, in the case of PDP, it has a great influence on the luminous intensity.

Accordingly, an object of the present invention is to provide a front electrode capable of forming a transparent electrode by printing, as well as being able to efficiently use the transparent electrode for image display.

1 is a cross-sectional view showing a general configuration of a flat panel display device;

2 is a plan view thereof;

3 is a plan view showing a configuration of a front electrode according to the present invention;

4 is a plan view showing another embodiment of the present invention.

* Description of the symbols for the main parts of the drawings *

P1, P2: Substrate B: Bulkhead

1: front electrode 2: metal electrode

2a: section 2b: branch section

2c: branch electrode 3: transparent electrode

In order to achieve the above object, the front electrode according to the present invention is a front electrode of a flat panel display device composed of a stack of transparent electrodes and a metal electrode, wherein the metal electrode is divided into a node and a branched portion therefrom. The repetitive arrangement is characterized in that the center of the node is located at the boundary line between the pixels and the center of the branch is located at the center of the pixel.

According to one feature of the invention, a transparent electrode is formed on this metal electrode, in particular by a printing method.

According to another feature of the invention, the transparent electrode is formed in a window surrounded by the elongated electrodes of the branch portions of the metal electrodes.

According to such a configuration, since the metal electrode anchors the transparent electrode, the transparent electrode can be formed by a printing method, thereby greatly reducing the process cost.

In addition, since the transparent electrode is formed on the metal electrode, the transparent electrode is not degraded by the firing of the metal electrode.

In addition, since the cross-sectional area of the metal electrode is narrowed between the node and the branch part, the movement path of the lowering of the electron lamp is narrowed, and the charges traveling through the metal electrode are diffused to the transparent electrode so that the entire area of the transparent electrode can be effectively used for image display. Will be.

In addition, since the front electrode can be positioned at the center of the pixel without lowering the light transmittance, efficient driving is possible.

EXAMPLE

Example 1

Such specific features and advantages of the present invention will become more apparent from the following description of the preferred embodiments with reference to the accompanying drawings.

In FIG. 3, the front electrode 1 is composed of a stack of a metal electrode 2 and a transparent electrode 3 as in the prior art, wherein the metal electrode 2 is a node portion 2a and the node portion according to the characteristics of the present invention. It consists of an alternating repeating arrangement of branching portions 2b branched from (2a) to a plurality of branch electrodes 2c. Here, the node portion 2a is positioned on the boundary line between each pixel, for example, in the case of PDP, on the partition wall B, and each branch electrode 2c extends to the pixel between the partition walls B so that the branch portion 2b is formed. The center of is approximately located at the center of the pixel.

Accordingly, the metal electrode 2 of the present invention repeats branching and convergence when viewed in the longitudinal direction.

According to this configuration, the cross-sectional area of the metal electrode 2 used as the bus electrode, that is, the cross-sectional area of the conductive path of charge, is repeated to expand and contract along the longitudinal direction. Therefore, the electric charge of electrons moved to the metal electrode 2 is suddenly reduced at the boundary between the node portion 2a and the branch portion 2b, so that it can diffuse to the transparent electrode 3 along the path of least resistance. There will be only one.

As a result, the electric charge is supplied to the transparent electrode 3 at a higher charge density than the conventional transparent electrode T shown in FIGS. 1 and 2, so that the entire area of the transparent electrode 3 is effectively used for image display. It can be used.

Here, the transparent electrode 3 is preferably formed on the metal electrode 2 unlike the prior art. Then, since the transparent electrode 3 is anchored by the metal electrode 2, it is possible to maintain the straightness even when formed by the printing method. do.

In particular, in the present invention, a window surrounded by the branch electrodes 2c of the branching and converging branch 2b is formed, and the transparent electrode 3 is formed in the window formed by the branch electrodes 2c.

Then, the four sides of the transparent electrode 3 are completely surrounded by the branch electrode 2c of the branching part 2b, so that the transparent electrode 3 is completely anchored by the branch electrode 2c even if the transparent electrode 3 has poor adhesion to the substrate P1. As a result, a clean pattern can be obtained by printing.

This makes it possible to achieve the pattern formation of the transparent electrode 3, which can not but rely on the conventional thin film method, by the inexpensive printing method, resulting in a significant reduction in the process cost, as well as transparent by the firing of the metal electrode 2. It is possible to fundamentally prevent deterioration of the electrode 3 to maintain the conductive characteristics of the transparent electrode 3.

On the other hand, the configuration of the present invention allows the projection area of the metal electrode 2 on the pixel to be greatly reduced as compared with the prior art (see FIG. 2). To be placed in the center of the. This enables full emission of pixels in light emitting devices such as PDPs, resulting in improved light intensity, and guarantees fastness and high contrast ratio even in non-light emitting devices such as LCDs. Done.

In the embodiment of FIG. 3, the branch electrodes 2c of the branching portion 2a are formed in two and extend in a straight bending path to form a rectangular window. In addition, the two electrodes 2c take a curved path. It is possible to form an elliptical or fusiform window.

Example 2

On the other hand, in the embodiment shown in Figure 4 by configuring the branch electrode (2c) of the branching portion (2b) 3 or more to configure a plurality of windows between them.

This configuration can not only obtain a better print quality when printing the transparent electrode 3, but also can further improve the driving characteristics of the PDP or LCD by distributing the charge distribution in a large area.

As described above, according to the present invention, a transparent electrode can be efficiently used, high brightness and high characteristics can be realized, and a front electrode can be provided which can greatly reduce the manufacturing cost of the device by forming by printing.

Claims (5)

In the front electrode of a flat panel display device comprising a transparent electrode and a metal electrode laminated, The metal electrode is composed of a repetitive arrangement of the branch portion and the branch portion branched therefrom into a plurality of branch electrodes, And a center of the node portion is at a boundary line between pixels, and a center of the branch portion is located at the center of the pixel. The method of claim 1, And the transparent electrode is formed in a window formed by a plurality of branch electrodes of a branch portion of the metal electrode. The method according to any one of claims 1 to 2, The front electrode of the flat panel display device, characterized in that the transparent electrode is formed by a printing method. The method of claim 2, And two branch electrodes to form a rectangular, oval or fusiform window between them. The method of claim 2, And three or more branch electrodes forming two or more windows therebetween.