KR20030073365A - The Flat display device - Google Patents

Abstract

PURPOSE: A color flat panel display device is provided to reduce manufacturing costs, the weight, and the volume by using a printing structure of a CNT instead of a wire cathode. CONSTITUTION: A color flat panel display device includes a back cover(30), a lower electrode, an electron emission source, a hopping portion(31), a plurality of modulation/focusing/deflection electrodes(32), and a phosphor layer(34). The lower electrode is formed on an upper face of the back cover(30). The electron emission source is formed on an upper face of the lower electrode. The electron emission source emits electron beams by a lead-in electrode. The electron beams are outputted to the phosphor layer(34) through the hopping portion(31) and the modulation/focusing/deflection electrodes(32). The electron emission source is formed with a CNT(Carbon Nano Tube).

Description

Color flat display device

The present invention relates to a color flat panel display device, which manufactures cathode electrodes by printing carbon nanotubes (CNTs), and provides modulation, focusing, and deflection electrodes as print electrodes to maintain high quality, low manufacturing cost, and low weight and volume. A color flat display element that can be minimized.

In general, a cathode ray tube is a vacuum tube configured to produce an image therein by hitting a fluorescent surface with an electron beam. Most monitors and TVs use a CRT as a display device.

As a conventional color television image display device, a cathode ray tube is mainly used, but the inner depth of the cathode ray tube is considerably longer than that of the screen, and it is impossible to produce a thin television receiver. Therefore, EL display elements, plasma display elements, liquid crystal display elements and the like have been developed as flat panel display elements, all of which are insufficient in terms of performance such as brightness, contrast, color reproducibility, and the like.

In the prior art, a high quality image comparable to a CRT is displayed on a flat-panel apparatus using an electron beam, and the screen on the screen is divided into divisions on a matrix, and the fluorescent beam is emitted by deflecting the electron beams for each division to generate a color as a whole. The image display apparatus which comprises a television image is proposed.

1 is a block diagram of a conventional color flat display apparatus.

Rear wall 10, back electrode 11, cathode filament 12 as electron beam source, electron beam control electrode 13, signal modulation electrode (14), focusing electrode (15), H-deflection electrode (16), V-deflection electrode (17), face plate (18), It consists of a unit cell 19.

The front cathodes 12 are provided in the horizontal direction so as to generate electron beams uniformly distributed in the horizontal direction, and the plurality of the front cathodes 12 are provided in the horizontal direction while maintaining appropriate intervals. These cathode electrodes 12 are formed by coating an oxide material on the surface of a tungsten wire. The back electrode 11 is made of a flat conductive material and is provided in parallel with the linear cathode 12. The lead electrode 13 is positioned in the screen direction above the front cathode 12 and is provided to face the rear electrode 11 and is conductive.

The signal electrodes 14 are arranged at predetermined intervals at positions where the through-holes in the lead-out electrode 13 are opposed to each other, and are arranged in rows of thin and long conductive plates in a plurality of vertical directions. Each conductive plate has through holes at positions facing each other of the through holes of the lead-out electrode 13. The focusing electrode 15 is a conductive plate having through-holes at positions opposite to the through-holes of the signal electrode 14, respectively. The focusing electrode 15 has a through hole at a position opposite to the through hole of the signal electrode 14. The horizontal deflection electrodes 16 are formed of a conductive plate at appropriate intervals on the same plane.

The vertical deflection electrodes 17 are formed so as to engage the conductive plates with each other at appropriate intervals on the same plane.

Referring to the operation of FIG. 1, first, the heater cathode is heated by flowing a heater current to facilitate electron emission. In a heated state, an appropriate voltage is applied to the back electrode 11, the front cathode 12, and the lead-out electrode 13 to emit an electron beam from the surface of the front cathode 12. The electron beam is divided into a plurality of through-holes of the lead-out electrode 13 to form a plurality of electron beams. This electron beam flows out according to the image signal applied to the signal electrode 14, and the electron beam passing through the signal electrode 14 is focused and shaped by the electrostatic lens effect of the through hole of the focusing electrode 15, and then the horizontal deflection electrode. (17) are horizontally and vertically deflected by a potential difference applied to the conductive plates adjacent to each other and the conductive plates adjacent to the vertical deflection electrodes 16. In addition, a high voltage (for example, 10 Kv) is applied to the metal back layer of the screen, and the electron beam is accelerated to high energy to collide with the metal back layer to emit the phosphor. When the television screen is divided into a matrix and a collection of subdivisions is made, the full screen can be projected on the screen by deflecting and scanning each subdivision. In addition, a television video is reproduced by controlling the RGB video signal corresponding to each image with a signal electrode.

All the above-mentioned electrodes are made of Invar (Fe-Ni Alloy). The screen is constructed by applying a phosphor, which is emitted by irradiation of an electron beam, to an inner surface of a glass container, on which a metal back layer (not shown) is added.

The lead electrode 13, the signal electrode 14, the focusing electrode 15, the horizontal deflection electrode 16 and the vertical deflection electrode 17 are each bonded by an insulating adhesive.

On the other hand, Figure 2 shows a conventional electrode assembly process.

In the process of assembling the electrode, the thermal process is performed by inserting a high melting point amorphous glass spacer and a low melting point crystalline glass rod between the electrodes. ) Melts to cover the amorphous glass spacer and serves as an inter-electrode adhesive. At this time, the diameter of the amorphous glass spacer maintains the inter-electrode gap. In addition, these electrode assemblies are equipped with eight stud pins (for 14 ") on the back plate 10 and sealed by frit glass, and an Invar frame is installed on the stud pins. It is installed above.

Conventionally, in order to drive first, electrons are emitted only when the front cathode 12 is heated to 750 ° C. or higher, and, due to this driving mechanism, 70% or more of the electron beam generated at the cathode during the driving impinges on the electron beam extraction electrode 13 to lead the extraction electrode. The temperature of (13) is heated to 80-150 ° C., causing deformation by heat and affecting the subsequent path of the electron beam.

This will eventually affect the color purity of the screen. In order to prevent this, an expensive metal material having low thermal expansion, that is, Invar (Fe-Ni Alloy) is used, which has a problem of high material cost and eventually high production cost.

Second, the prior art is bonded using an expensive glass rod between the electrodes in order to assemble the electrode, so the manufacturing cost is high because it goes through three or four electrode assembly heat process.

On the other hand, in the conventional electrode assembly procedure, first, the lead-out electrode and the signal electrode focusing electrode are plastically bonded (1 group), and the horizontal / vertical deflection electrode is plastically bonded (2 group) firstly, Plastic combination of two groups (three times) has a high manufacturing cost problem.

In addition, there is a conventional technique of employing a ceramic in the color brown tube, but due to the high sintering temperature of the ceramic, the manufacturing process is complicated and the material cost is high.

Third, since the support structure for supporting the electrode assembly in the glass is only the frame, when the size is enlarged, the center of the electrode sag occurs, which affects the electrostatic lens, resulting in deterioration of image quality and quality.

Fourth, wire cathode is used and pulse signal is electrically input, which causes quality deterioration due to wire vibration problem, and it is very difficult to implement over 21 "in size, and the structure is complicated because damping structure needs to be attached. Will result.

The present invention is to solve the above problems, the cathode electrode is produced by printing the CNT, and provided with a color flat panel display element such as a modulation electrode, focusing electrode, horizontal deflection electrode, vertical deflection electrode, as a print electrode, Solving thermal problems eliminates the need for expensive Invar electrodes, lowers manufacturing costs, and uses printed electrodes instead of conventional Invar electrodes and glass rods to simplify manufacturing and minimize weight and volume. It is an object of the present invention to provide a color flat display device that can be enlarged in a simple structure as the vibration problem associated with the cathode is eliminated by using CNTs by printing, and the vibration problem is solved.

1 is a schematic diagram of a conventional color plane display device.

Figure 2 is a conventional electrode assembly process diagram.

3 is an electronic hopping conceptual diagram.

4 is a structural diagram of a display device of the present invention;

Figure 5 is a detailed view of the hopping portion of the present invention.

6 shows a printed electrode.

7 is a detailed view of a print electrode of the present invention.

Description of the main parts of the drawing

31 hopping part 32, 45 modulation / focusing / deflection electrode

42: cathode electrode 50, 55: printed electrode

The present invention for achieving the above object is a back cover and a lower electrode provided on the back cover, the electron emission source formed on the upper surface of the lower electrode is an electron beam is emitted by the extraction electrode provided on the upper surface and the electron beam is a hopping part And a plurality of electrodes for modulating, focusing, and deflecting the light emitting phosphors on the front glass to form a screen.

In addition, the electrode of the present invention uses a print electrode, the print electrode is characterized in that the dielectric having a thickness of 30-200um, and a metal thin film of 2-20um on the dielectric, an insulator spacer between the electrode and the electrode It is provided by a printing method and the thickness is 200um or less, the dielectric is PbO, B ₂ O ₃ which is a glass raw material, the metal thin film is characterized in that at least one containing Au, Pt, Ag, Cu, Ni.

In addition, the present invention is characterized in that the cathode electrode is provided by printing the CNT.

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

3 is a conceptual diagram in which electrons move while hopping when power is applied to a lower electrode of a color flat panel display.

Secondary electrons are generated by injecting electrons from the emitter into the funnel. Applying an electromagnetic field to these secondary electrons causes electrons to move by hopping.

4 is a structural diagram of a color flat panel display.

The back cover 30 and the hopping part 31, the modulation / focusing / deflection electrode 32, the inner support 33, the screen phosphor 34, which is applied to the inside of the screen to emit light when the electron beam strikes, the front cover It is made of 35.

A hopping part 31 which serves to move and focus secondary electrons generated from the lower electrode positioned on the back cover 30, and a modulation electrode 32 which modulates electrons passing through the hopping part 31 according to an external signal. ), An internal support having a focusing electrode 32 for focusing the electron beam, a deflection electrode 32 having a function of deflecting the focused electron beam horizontally and vertically, and capable of resisting atmospheric pressure between the deflection electrode 32 and the screen ( 33), and the inner support 33 can be removed through glass optimization design by adopting thick glass in small and medium sized display devices, but the weight becomes heavy when using thick glass in a large device structure. Since there is a disadvantage, an inner support 33 is required. The front cover (screen) 35 is structurally provided on the inner support 33.

Referring to FIG. 4, first, a lower electrode and a cathode are positioned on the back cover 31, and an extraction electrode for drawing an electron beam is disposed on the cathode, and a potential difference is formed by applying an appropriate voltage to the lower electrode. Electrons are taken out of the electrode. The cathode of the present invention is to produce a carbon nanotube (CNT) by the printing method.

On the other hand, the electrons drawn from the extraction electrode exit the funnel-shaped hopping portion 31 narrowing in the screen direction while hopping. The plurality of electron beams exiting the hopping part 31 are controlled by the modulation electrode / focusing electrode / horizontal and vertical deflection electrode 32 to correspond to an image signal applied to a signal electrode made of a dielectric and a metal component. The passage amount passing through the signal electrode is adjusted individually for each electron beam flow. Next, the electron beam passing through the signal electrode is focused and shaped by the electrostatic lens effect of the through hole of the focusing electrode, and then deflected horizontally and vertically by a potential difference applied to adjacent conductive plates of the horizontal and vertical deflection electrodes.

The high voltage is applied to the metal back layer of the front cover (screen) 35, the electron beam is accelerated to high energy to impinge on the metal back, and when the phosphor 34 emits light, the screen is displayed on the front cover 35. .

FIG. 5 is a detailed structural diagram of the hopping part 31 of FIG. 4.

A lower electrode 40 is disposed below the hopping part 31, and a cathode electrode 42 is disposed on the lower electrode 40, and an extraction electrode 41 is provided on the cathode electrode 42 to extract an electron beam. On the inner surface of the hopping portion 31 is a MgO-coated MgO layer 43 to facilitate the generation of secondary electrons, and the modulation / focus / deflection electrode 45 on the top of the hopping portion 44 Will be located. On top of the modulation / focusing / deflection electrode 45, an inner support 33 for supporting atmospheric pressure made of glass or ceramic is positioned as shown in FIG. 4, and a front cover (glass) 35 having a screen is positioned thereon. Done.

The cathode 42 is formed by coating a metal as a lower electrode on the glass used as the back cover 30 and forming CNTs by printing on the upper surface to dry the cathode 42.

The day extraction electrode 41, in which the extraction electrode 41 for extracting the electron beam is positioned on the cathode 42, may be formed on the cathode 42 by printing or may be mounted by a separate mounting structure.

On the other hand, the present invention relates to the cathode electrode 42 is made of CNT material, and to manufacturing the modulation electrode, focusing electrode, vertical, horizontal deflection electrode as a printed electrode (printed electrode).

6 and 7 illustrate that the modulation electrodes, the focusing electrodes, the vertical and horizontal deflection electrodes, etc. of the present invention are generated as the printed electrodes 50 and 55.

The print electrode 55 is preferably used as an electrode by forming a metal thin film of 2-20um on the 30-200um dielectric.

The modulation electrode, focusing electrode, vertical and horizontal deflection electrodes 32 are fabricated by coating a thin metal film on the dielectric.

As the material of the metal thin film constituting the plurality of electrodes, at least one of Au, Pt, Ag, Cu, and Ni is preferably included as a material whose main component is a metal having excellent conductivity.

At this time, since the thickness of the dielectric and the electrode only needs to serve as a basic electrode, if the thickness is too thick, the manufacturing cost is high, and if the thickness is too thin, it is likely to be broken.

The printing method is patterning and drying the conductive silver paste by printing. Next, the dielectric material is again patterned on the silver paste and dried. Again, there is a method of baking the silver paste by patterning it on top, or a method of making a dielectric first and printing the silver paste on the surface thereof.

The silver paste, which is a conductive thin film (metal thin film), may be formed on the entire surface of the dielectric surface, but is preferably formed only around the through hole through which the electron beam passes in consideration of the efficient use of the material.

At this time, the frit glass used as a dielectric material (glass frit) are mainly composed of PbO or B ₂ O _3.

In manufacturing the printed electrode by the printing method, it is important to control the thermal expansion coefficient and the temperature profile of the temperature rising and falling of the material forming the dielectric and the conductive thin film in order to prevent the splitting of the conductive thin film during the firing which applies the thermal properties of the conductive thin film and the dielectric layer. Design is important.

When printing the electrode, the thickness of the conductive thin film is appropriately 20um or less, and the thickness of the electrode is appropriately 200um or less in view of maintaining its own strength and cost.

The electrodes, such as the modulation electrode, the focusing electrode, the vertical and horizontal deflection electrodes 32, manufactured by the above-described method, are formed of three layers of a silver paste, a dielectric, and a silver paste, which are conductive thin films, to complete the electrodes. Moreover, it is also preferable that the said many electrode mixes the said printed electrode and the electrode of a metal plate structure.

When installing the modulation electrode, focusing electrode, vertical and horizontal deflection electrodes 32, spacers of an insulator are used to maintain a constant gap between the electrodes.

The insulator spacer may also be manufactured by the above-described printing method to maintain a predetermined interval between the electrodes such as the modulation electrode, the focusing electrode, the vertical and horizontal deflection electrodes 32, and may be fabricated by printing the patterned insulator. It is made and arranged at regular intervals on the electrodes such as the modulation electrode, focusing electrode, vertical, horizontal deflection electrode 32, and then the upper electrode is aligned with the lower electrode and fired to maintain the gap between the electrodes and act as a binder between the electrodes. . In addition, when all of the electrodes are manufactured by printing, there is a risk of brittleness because of weak brittleness. Therefore, the extraction electrode and the focusing electrode of the plurality of electrodes may be taken as a structure to be reinforced with a metal.

As described above, the present invention eliminates the use of expensive Invar electrodes by solving the thermal problem by manufacturing and forming CNTs by printing instead of the wire cathodes used as hot cathodes, and thus, inexpensive manufacturing cost and By using printing structure instead of glass rod, manufacturing is simple and weight and volume can be minimized.The vibration problem associated with wire cathode is eliminated by using CNT, and the size can be enlarged with simple structure as vibration problem is solved. By providing an internal structure corresponding to the atmospheric pressure, it is a large-size structure for vacuum pressure.

Claims (12)

The back cover, the lower electrode provided on the upper surface of the back cover, and the electron emission source formed on the upper surface of the lower electrode emit an electron beam by the extraction electrode provided on the upper surface, and the electron beam passes through a hopping part to modulate, focus, and deflect a plurality of electrodes. Flat panel display device characterized in that to form a screen by emitting a phosphor applied to the front glass. The method of claim 1, The electron emission source is a flat panel display device, characterized in that the carbon nanotube (CNT) The method of claim 2, And the electron emission source is formed by printing. The method of claim 1, And the hopping portion has a funnel shape that narrows in the screen direction. The method of claim 2, The hopping part is a flat panel display device, characterized in that MgO is coated on the inner surface of the glass material. The method of claim 2, The thickness of the hopping portion is a flat panel display device, characterized in that 300 ~ 600um The method of claim 1, At least one of the plurality of electrodes is a flat panel display device characterized in that the structure of the metal thin film coated on the dielectric The method of claim 7, wherein The plurality of electrodes are a flat panel display device characterized in that the structure of the metal thin film coated on the dielectric and the metal plate structure is mixed The method of claim 7, wherein The metal thin film is a flat panel display device comprising at least one of Au, Pt, Ag, Cu, Ni The method of claim 7, wherein The dielectric is a flat panel display device, characterized in that at least one of PbO or B ₂ O ₃ is the main component The method of claim 7, wherein The plurality of electrodes is a flat panel display device, characterized in that produced by the printing method The method of claim 1, Insulator spacers are formed between the electrodes and the electrodes.