JP2712811B2 - Image display device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an image display device in a video device.

2. Description of the Related Art Conventionally, a cathode ray tube is mainly used as a display device for displaying color television images, but a conventional cathode ray tube has a very long depth compared to a screen, and a thin television receiver is manufactured. It was impossible to do. Recently, EL display devices, plasma display devices, liquid crystal display devices, etc. have been developed as flat display devices.
All of them are insufficient in performance such as luminance, contrast, and color reproducibility of color display, and require time for practical use. In view of the above, an object of the present invention is to achieve a device capable of displaying a color television image on a flat display device using an electron beam. Each time, the electron beam is deflected in the vertical direction to display a plurality of lines, and further divided into a plurality of sections in the horizontal direction, and the phosphors such as R, G, B are sequentially emitted for each section, so that the The irradiation amount of the electron beam to the phosphor such as R, G, and B is controlled by a color video signal, so that a television image display element is formed as a whole.

Hereinafter, an example of the above-described conventional image display device will be described with reference to the drawings. FIG. 3 and FIG. 4 show a conventional image display device. In FIG. 3, 1 is a line cathode as an electron beam source, 2a and 2b are supports for supporting and fixing both ends thereof, 3 is a mesh-shaped control electrode, 4 is a phosphor, 5 is a back electrode, 6a, Reference numeral 6b denotes a container, and 7 denotes a spring which is provided to apply a load to the linear cathode 1.

The operation of the thus configured image display device will be described below. The linear cathode 1 as an electron beam source is horizontally erected by a leaf spring 7 attached to the supports 2a and 2b so as to generate an electron beam distributed linearly in the horizontal direction. Are provided at appropriate intervals. (Here, only seven wires are shown.) This is shown enlarged in FIG. The linear cathode 1 is supported by an insulating support 2 b fixed to the back electrode 5 and fixed by a leaf spring 7. The distance between the linear cathode 1, the control electrode 3 and the back electrode 5 is important in order to eliminate the variation in the luminance. For this reason, the pitch and depth are measured using an optical measuring device or the like. The V-groove 8 is processed at one location and within an error of several μm or less. These line cathodes 1 are formed by coating an oxide cathode material on the surface of a tungsten wire of, for example, φ10 to 20 μm. Then, control is performed by a control pulse so as to sequentially emit an electron beam at a constant time, and a heat current is supplied to raise the temperature to generate an electron beam at a time other than the predetermined time. At the start, the linear cathode 1
, The control pulse for the electron beam emission and the heat current are loaded at the same timing. The back electrode 5 suppresses the generation of electron beams from the other linear cathodes 1 other than the linear cathode 1 that is controlled to emit the electron beams at regular intervals, and pushes out the generated electron beams only in the forward direction. Works. The mesh-like control electrode 3 is passed through each opposed horizontally long slit of the linear cathode 1, and is simultaneously deflected in the vertical or horizontal direction. A round hole may be used instead of the slit. The phosphor 4 applies R, G, B to each one of the electron beams divided in the horizontal direction.
Are provided one by one, and are applied in stripes in the vertical direction. After these components are inserted into the divided containers 6a and 6b, they are sealed via a frit or the like to maintain the internal vacuum.

However, in the above configuration, as described above,
A spring 7 for stretching the linear cathode 1 is disposed outside the insulating supports 2a and 2b, and is a container that does not contact the spring 7.
6a and 6b are required. Therefore, there is a problem that the outer dimensions of the containers 6a and 6b are increased.

The present invention solves the above-mentioned problem, and supports a spring without increasing the outer dimensions of a container.

Means for Solving the Problems To solve the above problems, the image display device of the present invention,
Insulating supports having grooves for guiding the line cathodes are arranged at both ends of the back electrode, and the ends are fixed to the surfaces of the insulating supports at both ends facing each other, and the other ends are insulated from the back electrode. A spring located outside the body is provided, and a linear cathode is fixed to the other end of the spring.

According to the present invention, the line cathode is fixed to the other end of the spring whose end is fixed to the surface on the side where the insulating support faces each other and which is located outside the insulating support when viewed from the back electrode. This makes it possible to shorten the span dimension of the linear cathode and to reduce the outer dimensions of the container and make it compact.

Embodiment Hereinafter, an image display device according to an embodiment of the present invention will be described with reference to a screen. In FIG. 1, 11 is a conductive line cathode coated with a material having a thermionic emission function such as barium oxide, 12a and 12b are insulating supports for supporting both ends of the line cathode 11, and 13 is the line cathode. An electrode for controlling the electron beam emitted from the cathode 11 so as to form a predetermined image, 14 is a phosphor that emits light when the electron beam passing through the control electrode 13 collides and displays an image, and 15 is a line cathode 11 Back electrodes installed so that thermoelectrons are easily generated from them, 16a and 16b are containers, 17a and 17b are insulators for positioning the line cathode 11 in the height direction, and 18 is a It is a tension spring. In FIG. 1, insulators 17a, 17
The line cathode 11 is provided with b, and the distance between the back electrode 15 and the control electrode 13 is maintained by contact with the outer diameter. Further, as shown in FIG. 2, the line cathode 11 is fixed behind the insulating support 12b, passes through the lower part, and is fixed at the tip of a spring 18 located outside the insulating support 12b. For that reason,
The effective stroke of the spring 18 is as large as the thickness of the insulating support 12b.
It is possible to reduce the length of the linear cathode 11 to be shortened. Further, the spring 18 cannot be bent inwardly than the thickness of the insulating support 12b, and can control that the tension of the linear cathode 11 is unnecessarily applied.

The image display device is completed by assembling the control electrode 13 and the like on the assembled rear electrode 15 and sealing them with the containers 16a and 16b.

Effect of the Invention As described above, the present invention arranges an insulating support having a groove for guiding a line cathode at both ends of a back electrode, and the ends of the insulating supports at both ends are fixed to surfaces facing each other; A spring whose other end is located outside of the insulating support when viewed from the back electrode is provided, and the linear cathode is fixed to the other end of the spring to shorten the span of the linear cathode, and It is possible to provide a compact image display device having a small external dimension.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an image display device according to an embodiment of the present invention, FIG. 2 is an enlarged sectional view of a main part of a back electrode block,
FIG. 3 is a partially cutaway perspective view showing a conventional image display device,
FIG. 4 is an enlarged sectional view of the main part. 11 ... Line cathode, 12a, 12b ... Insulating support, 13 ... Control electrode, 14 ... Phosphor, 15 ... Back electrode, 18 ... Spring.

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-121239 (JP, A) JP-A-60-193246 (JP, A) JP-A 52-74752 (JP, U)

Claims (1)

(57) [Claims] 1. A line cathode for emitting electrons, a control electrode for controlling the flow of electrons, a phosphor capable of receiving and emitting the electrons, and a back electrode provided to emit the electrons from the line cathode. In the image display device having, the insulating support having a groove for guiding the linear cathode is disposed at both ends of the back electrode, the end is fixed to the surface of the insulating support at both ends facing each other, and the other A spring whose end is located outside the insulating support when viewed from the back electrode is provided,
An image display device, wherein the line cathode is fixed to another end of the spring.