JPH02117054A - Image display device - Google Patents

Abstract

PURPOSE:To enable an image of high quality to be obtained by having wire cathodes come in contact with one or more insulating wires, and furthermore having these wires come in contact with plural metallic plates so that the oscillation of the wire cathodes is suspended. CONSTITUTION:Each wire cathode 30A through 30D is made to be in tension by means of a wire cathode spring 35 in order to be strength tight. And each wire cathode 30A through 30D is brought in contact with an insulating wire 31 in such a way that the wire is knitted together. In addition, the insulating wire 31 is brought in contact with an insulating wire restraining metallic plate 32 while being formed in a wave shape. In this case, when external force is applied, each wire cathode 30A through 30D starts oscillating at its characteristic frequency so that friction is caused between each wires cathode 30A through 30D and the insulating wire 31. And the insulating wire 31 also concurrently starts oscillating so that friction is caused halfway the distance to the insulating wire restraining metallic plate 32. As a result, the oscillating energy of each wire cathode 30A through 30D is converted into friction energy so that the oscillation of each wire cathode 30A through 30D is damped instantly so as to be suspended. By this constitution, an image of high quality can thereby be obtained stably.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an image display device for video equipment.

Conventional technology Conventionally, cathode ray tubes have been mainly used as color television image display elements, but cathode ray tubes have a much longer depth than the screen, making it impossible to manufacture flat-screen television receivers. Ta. Therefore, EL display elements, plasma display elements, liquid crystal display elements, and the like have been developed as display elements on a flat panel, but all of them are insufficient in terms of performance such as brightness, contrast, and color reproducibility. Therefore, with the aim of displaying high-quality images comparable to those on a cathode ray tube using a flat-panel device that uses electron beams, the screen is divided into matrix-like sections without gaps, and the electron beam is applied to each section. This is an image display device that performs deflection scanning to cause phosphors to emit light, thereby forming a color television image as a whole. An example of the conventional image display device mentioned above will be described below with reference to the drawings.

FIG. 2 shows the configuration of a conventional image display device. In Figure 2, 1 is a back electrode, 2 is a line cathode as an electron beam source, 3 is an electron beam extraction electrode, 4 is a signal electrode, 5 and 6 are focusing electrodes, 7 is a horizontal deflection electrode, and 8 is a vertical deflection electrode. Yes, these components are placed in glass containers 9, 10.
It is stored in a container and the inside of the container is evacuated. line cathode 2
is stretched in the horizontal direction so as to generate an electron flow uniformly distributed in the horizontal direction, and a plurality of wire cathodes 2 (herein, 2-2 to 2-4) are arranged vertically at appropriate intervals. (Only books shown) provided. These wire cathodes are constructed, for example, by coating the surface of a tungsten wire with an oxide cathode material. The back electrode 1 is made of a flat conductive material,
It is provided in parallel to the line cathodes 2a-22. The extraction electrode 3 is made of a conductive plate that faces the back electrode 1 via the line cathodes 2a-22 and has a row of through holes 11 provided at appropriate intervals in the horizontal direction on a horizontal line facing each line cathode. Although the through hole 11 is circular in the embodiment, it may be oval or rectangular, or may be slit-shaped. Signal electrode 4
consists of a row of vertically elongated conductive plates 12 arranged at predetermined intervals in positions facing each of the through holes 11 in the extraction electrode 3, and each conductive plate has a through hole of the extraction electrode 8i3. A similar through hole 13 is provided at a position opposite to 11. The shape of the through hole 13 may be an ellipse or a rectangle, or may be a vertically elongated slit. The focusing electrode 5 is connected to the through hole 13 of the signal electrode 4.
and a conductive plate having through holes 14 at positions facing each other. The shape of the through hole 14 may be a circle, an ellipse, or a slit. The focusing electrode 6 has a vertically connected slit hole 15 at a position facing the through hole 14 of the focusing electrode 5 . The shape of the slit hole 15 may be round, oval, or rectangular. The horizontal deflection electrode 7 is composed of two conductive plates 16 and 17 connected by comb-shaped ends that are interlocked with each other at an appropriate interval on the same plane, and is made between the conductive plates 16 and 17. The space 18 faces the through slit hole 15 of the five focusing electrodes 6. Vertical deflection electrode 8
are electrically conductive plates 19. connected at their ends as shown in FIG.
20, that is, two comb-shaped conductive plates 19 and 20 are arranged on the same plane and are interlocked with each other at an appropriate interval. The screen 21 is constructed by coating the inner surface of the glass container 9 with a phosphor 22 that emits light when irradiated with an electron beam, and adding a metal back layer (not shown) thereon. In addition, the above-mentioned extraction electrode 3. Signal 1 4. Focusing electrodes 5 and 6. The horizontal deflection electrode 7 and the vertical deflection electrode 8 are each bonded with an insulating adhesive (not shown here).
An integrated electrode block 24 is formed.

The operation of the image display device configured as described above will be briefly described.

First, a heater current is applied to the wire cathode 2 to heat it to facilitate electron emission. In the heated state, the back electrode 1, the wire cathode 2.
A suitable voltage is applied to the extraction electrode 3 to emit a sheet-like electron beam from the surface of the linear cathode 2. The sheet-like electron beam is divided into a plurality of parts by the through hole 11 of the extraction electrode 3, and becomes a large number of electron beam streams 23. This electron beam flow 2
3, the amount of passage of each electron beam stream is individually adjusted by the signal electrode 4 in accordance with the video signal applied to the signal electrode 4.

Next, the electron beam that has passed through the signal electrode 4 is directed to the focusing electrode 5,
After the focusing 2 is formed by the electrostatic lens effect of the through holes 14.1.5 of the horizontal deflection electrodes 7, the adjacent conductive plates 16.
It is deflected horizontally and vertically by the potential difference applied to the adjacent conductive plates 19 and 20 of the vertical deflection electrode 17 and the vertical deflection electrode 8. Further, a high voltage (for example, 10 KV) is applied to the metal back layer of the screen 21, and the electron beam is accelerated to high energy and collides with the metal back, causing the phosphor 22 to emit light.

When a television screen is divided vertically and horizontally into a matrix to form a collection of subsections 75, one electron beam separated as described above is associated with each subsection, and the electron beam is divided into each subsection. Deflection only within.

By scanning, the entire image can be displayed on the screen. Furthermore, by controlling the RGB video signals corresponding to each pixel using signals 1 to 4, television moving images can be reproduced.

Problems to be Solved by the Invention In the configuration as described above, the following problems have been encountered in order to constantly obtain high-quality images.

As shown in Figure 3, 1. The wire cathode 2 is a thin wire with a diameter of several tens of μm, and both ends (only one side is shown) have height regulating bars 2.
6 regulates the height, and a Y-direction positioning frame 27 performs positioning in the Y-direction. Further, a spring 28 attached to the Y-direction positioning frame 27 applies tension to both sides or one side.

When external vibrations are applied to the image display device equipped with the line cathode 2 positioned and stretched in this way, the line cathode 2 moves to the fourth position.
As shown in the figure, it starts vibrating mainly in simple harmonic motion and continues to vibrate until it stops damping. When the line cathode 2 vibrates, the amount of the electron beam flow (23 in Figure 2) passing through the through hole (11 in Figure 2) of the aforementioned extraction electrode (3 in Figure 2) changes periodically. (b) As a result, the brightness on the screen 21 changes periodically, making it impossible to stably obtain a high-quality image.

In view of the above problems, the present invention provides an image display device that can always stably obtain high-quality images.

Means for Solving the Problems In order to solve the above problems, the present invention provides the following features: This is designed to prevent vibration of the line cathode.

Function The function of the present invention is, as described above, when vibration of the wire cathode occurs due to an external force applied to the image display device due to the contact of the insulated wire to the wire cathode and the contact of the metal plate to the insulated wire. However, the insulated wire and metal plate absorb the vibration energy and act as a damper, stopping the vibration of the wire cathode and providing a stable, high-quality image.

Embodiment Hereinafter, an image display device according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows the structure of a line cathode extending portion of an image display device in an embodiment of the present invention. 30 i, 30 mouths,
30ha, 302 is a wire cathode, 31 is an insulated wire, 32
is an insulated wire regulating metal plate, 33 is a height regulating bar, 34
3 is a Y-direction positioning frame, and 35 is a wire cathode tension spring.

Although FIG. 1 only shows the structure of one end of the line cathode 300, the other end also has the same shape. line cathode 3
0 has its height regulated by a height regulating bar 33, and is further positioned in the Y direction by a Y direction positioning frame 34.

Each of the wire cathodes 30a, 30c, 30c, and 302 is stretched by being given tension by a wire cathode spring 35. In addition, the wire cathodes 30A, 30N, 30C, and 302 are woven with insulated wire 31 (in the example, one ceramic wire with a diameter of 15 μm was used, but of course there is no limit to the diameter and the number of wires). They are in contact with each other in shape. Furthermore, the insulated wire 31 is brought into contact with the insulated wire/regulating metal plate 32 in a wavy manner.

A case will be considered in which an external force such as vibration or shock is applied to an image display device having a line cathode stretching section configured as described above. When an external force is applied, the line cathode 30a.

30 mouth, 30 ha, and 302 start vibrating at their respective natural frequencies. At the same time as the vibration starts, the wire cathode 30, 30, 3
Friction occurs between the insulated wire 31 and the insulated wire 31, and the insulated wire 31 itself also vibrates, causing friction with the insulated wire regulating metal plate 32. As a result, the vibration energy of the wire cathode 30 is converted into frictional energy with the insulated wire 31, vibration energy of the insulated wire 2, and frictional energy between the insulated wire 2 and the insulated wire regulating metal plate 32, and the vibration of the wire cathode 30 is immediately reduced. Attenuates and stops.

Effects of the Invention As described above, according to the present invention, even when vibration of the wire cathode occurs due to an external force applied to the image display device, the insulated wire and the metal plate immediately absorb the vibration energy, act as a damper, and suppress the vibration of the wire cathode. It is possible to obtain stable, high-quality images by stopping the image.

[Brief explanation of drawings]

FIG. 1 is a partially exploded perspective view of a line cathode strut part of an image display device according to an embodiment of the present invention, FIG. 2 is a partially exploded perspective view showing the configuration of a conventional image display device, and FIG. FIG. 4, which is a partially exploded perspective view of a line cathode extending portion of an image display device, is a vibration mode diagram of a line cathode in a conventional image display device. 30i to 302... line cathode, 31...
Insulated wire, 32...Insulated wire regulation metal plate, 33...Height regulation knob

Claims (1)

[Claims] A front glass container whose inner surface is coated with phosphor, a back container facing the front glass container, and a plurality of back electrodes made of a single conductive plate in the space sandwiched between the back container and the front glass container. In an image display device equipped with a book line cathode, an extraction electrode made of one or more conductive plates, a signal electrode, a focusing electrode, a horizontal deflection electrode, and a vertical deflection electrode, the plurality of conductive plates An image display device characterized in that one or more insulated wires are brought into contact with both ends of all of the wire cathodes, and the insulated wires are brought into contact with a plurality of metal plates.