KR20020057327A - The FED's spacer grounded with focusing electrode - Google Patents

Abstract

PURPOSE: A field emission display grounding a spacer with a focus electrode is provided to readily mount the spacer and strongly support the longer spacer. CONSTITUTION: A field emission display comprises a gate electrode(420) for controlling electron emission amount of a cold cathode and a focus electrode(430) for focusing the emitted electron, and a spacer(410) for supporting between an upper plate and a lower plate. The gate electrode(420) and the focus electrode(430) are arranged at a same plane on the lower plate. The spacer(410) is a cross type spacer. The spacer(410) is arranged on the focus electrode(430). The spacer(410) is made of metal processed ceramic or glass. The top of the spacer(410) is attached to a black matrix of the upper plate. The height of the metal processing is adjusted depending on scattering amount of a beam in characteristic of an emitter(440).

Description

Field emission-type display device with a spacer grounded using a focusing electrode {The FED's spacer grounded with focusing electrode}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the field of spacer grounding of field emission display devices. In particular, in order to prevent charging by the spacer, the focusing electrode is installed on the same plane as the gate electrode to focus the electron beam coming from the emitter tip. The present invention relates to a field emission display device in which a spacer is grounded using a focusing electrode for easily mounting the spacer using a planar electron focusing electrode and a protruding black matrix.

The prior art uses a new pattern of technology outside the active area of the panel to erect spacers and then ground the spacers on top of them.

However, this technique is limited to very limited spacers and does not apply to spacers of cross or short rib type. It also has the negative side that the contact surface between the spacer and the metal coating becomes uneven.

When using a long rib spacer, a new jig should be mounted on the side to fix it. In the conventional method, a metal was coated on this part to make contact with the spacer. However, the short lip type or cross type has a difficulty in forming an electrode that can be an electrode inside the panel.

This spacer mounting is used very carefully because of the fact that the spacer can be seen during operation or arcing may occur in the portion thereof.

In addition, when using a long rib type spacer therein, a driving complexity may be generated by forming an electrode different from the focusing electrode and applying an electrode separately.

1 is a view showing an embodiment of a conventional method for forming a lip type spacer.

Referring to FIG. 1, the method of forming the lip type spacer 110 may be applied to driving a small display, but may not be applied to a large panel of 10 inches or more. And as the spacer 110 becomes longer, the breakage phenomenon of the corner portion of the spacer may occur, and it may be difficult to form it at a right angle, and it may fall down to one side. The jig is placed outside the active area of the field emission display device and grounded by fixing the metal coating 130 between the jig and the spacer.

Thus, most large panels must be equipped with the shape of a cross or a small lip, which faces the difficulty of pulling the ground electrode out.

2 is a view showing a coating of a metal on a common spacer.

Referring to FIG. 2, a shape of a general spacer 210 is shown. Usually, a thin metal strip 220 is placed on a wall surface of a spacer 210 to draw and charge electrons that are manufactured by mounting a thin sheet of ceramic or glass.

As described above, a metal band is placed on the ground plane of the bottom or a band is placed on the middle portion of the spacer. However, both of these methods have disadvantages that cannot be mounted unless the spacer has a long rib type.

3 is a view showing a conventional spacer grounded.

Referring to FIGS. 3A and 3B, a frit glass 330 is provided between a focusing electrode 310 and a spacer 320 to fix the spacer 320 and an electric field through a metal coating of the spacer. There is a drawback that depends on grounding outside the active area of the emissive display element.

The present invention has been made to solve the above problems, and the focusing electrode is installed on the same plane as the gate electrode, the spacer is easily installed through the use of the protruding black matrix, and the electron beam is focused while having the same electrode. In addition, an object of the present invention is to provide a field emission type display device in which a spacer is grounded by using a focusing electrode which is arranged to have a gate electrode higher than that of a long spacer, and which can be strongly supported when a long spacer is installed.

1 shows one embodiment of a conventional method of forming a lip type spacer.

2 is a view showing a coating of a metal on a common spacer.

3 is a view showing a conventional spacer grounded.

4 is a diagram illustrating a cross-type and lip-type spacer mounted in a field emission display device in which a spacer is grounded using a focusing electrode according to the present invention.

FIG. 5 is a diagram illustrating an embodiment in which a cross spacer is disposed on a focusing electrode in a field emission display device in which a spacer is grounded using the focusing electrode according to the present invention.

FIG. 6 is a diagram illustrating an embodiment in which a short lip spacer is disposed on a focusing electrode in a field emission display device in which a spacer is grounded using the focusing electrode according to the present invention.

FIG. 7 is a view illustrating an embodiment in which a spacer is grounded using a raised focusing electrode in a field emission display device in which a spacer is grounded using the focusing electrode according to the present invention.

Explanation of symbols on the main parts of the drawings

410: cross spacer 420: gate electrode

430: focusing electrode 440: emitter

In order to achieve the above object, a field emission display device having a spacer grounded using a focusing electrode according to the present invention includes a cold cathode serving as an electron emitting unit, a gate electrode controlling an electron emission amount of the cold cathode, and the emitted electrons. A lower substrate on which a focusing electrode for focusing is formed; An upper substrate having an anode, a red, blue, and yellow phosphor formed on the anode, and a black matrix formed on a boundary of the phosphor; In the field emission display device having a spacer for supporting between the upper substrate and the lower substrate,

The gate electrode and the focusing electrode are positioned on the same plane, and the spacers are formed on the focusing electrode and grounded.

Here, the spacer is formed of a ceramic or glass, characterized in that the one side contact with the focusing electrode is coated with a metal and the focusing electrode has a feature that has a structure that protrudes more than the gate electrode.

In addition, the other side of the spacer is configured to be connected to the black matrix layer, the height of the metal coating surface is characterized in that the height is adjusted according to the scattering degree of the beam due to the characteristics of the emitter.

In addition, the spacer is characterized in that it has a structure that is cross-shaped so as to be self-supporting and embedded in the protrusion structure of the black matrix layer.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

4 is a diagram illustrating a cross-shaped and lip-shaped spacer mounted in a field emission display device in which a spacer is grounded using the focusing electrode according to the present invention.

Referring to FIG. 4, first, a plan view in which a cross-shaped spacer 410 is mounted is shown in FIG. 4A, and the spacer 410 is a focusing electrode that is coplanar with the gate electrode 420. 430) the structure is on top.

The emitter 440 of the field emission device is made into a tip shape, and then the gate electrode 420 and the focusing electrode 430 are raised. Since a single mask is used, when connecting to a printed circuit board (PCB) later, It is only necessary to isolate the gate electrode and the focusing electrode.

Normally, a gate metal film applied to the field emission display device is made of an insulating layer such as chromium and niobium (Nb), and a metal having good adhesion. In the same plane as shown in FIG. 4, the same metal is the same as that of the gate electrode 420. Used as the focusing electrode 430.

However, this is not a problem in process or operation.

If only dry etching is not completely performed with respect to the isolation between the gate electrode 420 and the focusing electrode 430, the entire panel may be energized due to the occurrence of leakage currents.

The distance between the gate electrode 420 and the focusing electrode 430 is important. This is because the voltage applied to the gate electrode 420 should be grounded to the focusing electrode without affecting the focusing electrode. According to the simulation result, the distance between the gate electrode 420 and the focusing electrode 430 is constant at 5 µm to 10 µm and a reverse bias of -20 to -40 V is applied to the focusing electrode 430. Judging results showed that the electron beam safely entered the phosphor region of the anode plate.

Usually the size of the phosphor is 215 μm (length) x 60 μm (width) when the resolution is 5 inch QQVGA: Quarter Video Graphics Array (QQVGA). Even if the width should not exceed 100㎛ ~ 120㎛ on both sides.

As shown in (a) and (b) of FIG. 4, since the spacer is sufficiently raised on the focusing electrode, it is not a problem to extract the charge through the bias. And the spacers would stand without tilting to one side by using the protruding black matrix on the anode.

FIG. 5 is a diagram illustrating an embodiment in which a cross spacer is disposed on the focusing electrode in the field emission display device in which the spacer is grounded using the focusing electrode according to the present invention.

Referring to FIG. 5, the upper end of the metal-treated ceramic or glass spacer 510 is disposed on the black matrix 551 of the upper plate 550, and the focusing electrode 520 is brought into contact with the lower part 511.

The metal treatment of the spacer 510 may be adjusted according to the scattering degree of the beam due to the characteristics of the emitter 530. In general, co-planer focusing electrodes are less likely to focus electron beams than raised types, so metal treatment to some extent would be desirable.

FIG. 6 is a diagram illustrating an embodiment in which a short lip spacer is disposed on the focusing electrode in the field emission display device in which the spacer is grounded using the focusing electrode according to the present invention.

Referring to FIG. 6, short lip spacers are replaced with cross spacers in FIG.

7 is a diagram illustrating an example in which a spacer is grounded using a raised focusing electrode in a field emission display device in which a spacer is grounded using the focusing electrode according to the present invention.

Referring to FIG. 7, the spacer may be fixed to the raised focusing electrode 710 by the thickness of the spacer 720 and may be grounded at the same time. The raised focusing electrode 710 has many materials and methods that can be used, such as polyimide, screen printing, plating, or the like. However, in order to make the height constant at 20 ~ 30㎛ and to make the width of the spacer uniform, it is good to set the interval using the exposure method. Currently, polyimide or plating method is used. However, the plating method is easy in that the polyimide is difficult to process and has to be focused again by metal deposition. As known in the art, plating is performed by depositing a double layer of titanium / calcium (Ti / Ca), patterning using a thick resist, and then growing in a plating solution. Since this method can easily form electrodes, many applications are easy, and since the spacing between electrodes is used by a general exposure method, there is an advantage that it can be kept constant.

Tolerance can be adjusted between 5 ~ 10㎛ according to the size of patterning according to the fabrication of the mask and narrowing the tolerance of the black matrix area of the focusing electrode and the anode plate also makes it easy to display the arrangement of the upper and lower plates. Can be.

As described above, in the field emission display device in which a spacer is grounded using the focusing electrode according to the present invention, the focusing electrode is installed on the same plane as the gate electrode to focus the electron beam emitted from the emitter and at the same time the focusing electrode By protruding or modifying the structure of the black matrix, it is easy to mount the spacers that support the upper and lower plates of the field emission display device. Can be removed.

Claims (7)

A lower substrate having a cold cathode serving as an electron emitting unit, a gate electrode controlling an electron emission amount of the cold cathode, and a focusing electrode for focusing the emitted electrons; An upper substrate having an anode, a red, blue, and yellow phosphor formed on the anode, and a black matrix formed on the boundary of the phosphor; In the field emission display device having a spacer for supporting between the upper substrate and the lower substrate, And the gate electrode and the focusing electrode are located on the same plane, and the spacers are formed on the focusing electrode and grounded, wherein the spacers are grounded using the focusing electrode. The field emission type display device of claim 1, wherein the spacer is formed of ceramic or glass, and one side of the spacer contacting the focusing electrode is coated with a metal. The field emission display device of claim 1, wherein the focusing electrode has a structure protruding from the gate electrode. The field emission display device of claim 2, wherein the other side of the spacer is connected to the black matrix layer. The field emission display device of claim 2, wherein the height of the metal coating surface is adjusted according to the scattering degree of the beam due to emitter characteristics. The field emission display device of claim 4, wherein the spacers are cross-shaped so as to be self-supporting. 5. The field emission display device of claim 4, wherein the spacers have a structure inserted into the protruding structure of the black matrix layer. 6.