JPH03122951A - Image display device - Google Patents

Abstract

PURPOSE:To eliminate defects on an image such as uneven brightness by constructing a back face electrode in the form of a flat plate furnished with protrusions, providing an insulative support having a notch to admit insertion of this protrusion and fixed to the back face electrode, mounting a metal piece on this insulative support, and fixing the support to the back face electrode through this metal piece. CONSTITUTION:A back face electrode 15 is formed in a flat plate and provided with protrusions 20a-20d at the four corners, wherein the electrode was accomplished with no folding/bending process nor provision of tapped holes. Insulative supports 12a, 12b are provided with a notch 21 to mate with said protrusions 20a-20d on the electrode 15, and No.1 L-shaped metal pieces 22a, 22b are fastened by means of caulking, etc., so as to lie under this notch 21. A wire cathode 11 therefore contacts the peripheries of insulating members 17a, 17b and are held in precise spacing to the back face electrode 15 or a control electrode 13. Further, No.1 and No.2 L-shaped metal piece 23a, 23b prevent inclination of insulative supports 12a, 12b resulting from the tension of the wire cathode 11. Generation of uneven brightness can thus be precluded.

Description

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

Conventional technology Conventionally, cathode ray tubes have been mainly used as display elements for displaying color television images, but conventional cathode ray tubes have a much longer depth than the screen, making it difficult to manufacture thin television receivers. It was impossible to do so.

In addition, although EL display elements, plasma display elements, liquid crystal display elements, etc. have recently been developed as flat display elements, all of them are insufficient in terms of performance such as brightness, contrast, and color reproducibility. , it will take time to put it into practical use.

Therefore, we aimed to achieve a device that can display color television images on a flat display device using electron beams, and we divided the screen on the screen vertically into multiple sections. Each time, the electron beam is deflected vertically to display multiple lines, and
Divide into multiple sections horizontally and set R, G, B for each section.
The R, C, B phosphors are made to emit light sequentially, and
Hereinafter, with reference to the drawings, the above-mentioned conventional image An example of a display device will be described. 3 and 4 show conventional image display devices. In FIG. 3, 1 is a line cathode as an electron beam source, 2a and 2b are insulating supports that position both ends of the line cathode, 3 is a mesh-like control electrode, 4 is a phosphor, 5 is a back electrode, 6a and 6b are The container 7 is a spring that applies a load to the wire cathode and stretches it. 8 is a fixing seat for fixing the wire cathode 1.

The operation of the image display device configured as described above will be described below. Line cathode l as an electron beam source
The insulating supports 2a and 2b are attached to the back electrode 5 having the bent portions 9a and 9b with screws, etc., and then attached to the insulating supports 2b so as to generate an electron beam distributed linearly in the horizontal direction. One end of the wire cathode 1 is fixed to the flat spring 7, and the other end is fixed to the fixed seat 8, and the wire cathode 1 is stretched in the horizontal direction.

A plurality of wire cathodes 1 are provided at appropriate intervals (not shown), and the wire cathodes 1 are brought into contact with insulators 10a and 10b for positioning in the height direction.

This is shown enlarged in FIG. Line cathode 1 is φ10
It is constructed by coating an oxide cathode material on the surface of a ~20 μm tungsten wire. Then, it is controlled by a control pulse so as to sequentially emit an electron beam for a fixed period of time, and a heat current is applied at times other than the fixed period of time to raise the temperature to generate an electron beam. Further, at the start, the line cathode 1 is loaded with the above-mentioned electron beam emission control pulse and heat current at the same timing.

The back electrode 5 suppresses generation of electron beams from line cathodes 1 other than the line cathode 1 which is controlled to emit electron beams at fixed time intervals, and pushes out the generated electron beams only in the forward direction. act.

The mesh-like control II electrode 3 allows the electron beam to pass through horizontally long slits facing each of the line cathodes 1, and at the same time deflects it vertically or horizontally.

Also, a round hole may be used instead of the slit. The phosphors 4 are provided with one pair of phosphors of three colors, R, G, and B, for each electron beam divided horizontally, and are coated in stripes in the vertical direction. There is. After inserting these components into the divided containers 6a and 6b,
The internal vacuum is maintained by sealing with a frit or the like.

Problems to be Solved by the Invention However, in the above configuration, since the back electrode 5 is provided with the bent portions 9a, 9b, the bent portions 9a,
Distortion occurs during the bending process of the back electrode 9b, making it difficult to ensure the flatness of the back electrode 5, the line cathode 1,
Furthermore, the relative positional relationship with the control electrode 3 could not be ensured, resulting in uneven brightness as an image, which was a defect in the image.

In view of the above-mentioned drawbacks, the present invention does not provide a bent portion on the back electrode, and ensures the flatness of the back electrode by making it planar.
An object of the present invention is to provide an image display device that can eliminate brightness unevenness by also securing relative positions.

Means for Solving the Problems In order to solve the above problems, the image display device of the present invention has a back electrode in the form of a flat plate with no bent portion, a protrusion, and an insulator with a metal fitting. The insulating support is inserted into the notch of the support, and the insulating support is bonded and fixed to the back electrode via a metal fitting.

Function The present invention has the above-mentioned configuration, and since the back electrode is in the form of a flat plate, the flatness does not deteriorate due to distortions such as bending.Furthermore, since the present invention is in the form of a flat plate, even if the flatness is poor, thermal straightening is not possible. It has the effect that it can be carried out on a plurality of sheets at a time, that flatness can be easily ensured, and that the relative positional relationship with other electrodes can also be easily ensured.

Embodiment Hereinafter, an image display device according to an embodiment of the present invention will be described with reference to the drawings. In FIG. 1, 11 is a conductive wire cathode coated with a substance having thermionic emission function such as barium oxide, 12a and 12b are insulating supports that position and support both ends of this wire cathode 11, and 13 is the wire cathode. An electrode controls the beam emitted from the cathode 11 so that it becomes a predetermined image; 14 is a phosphor with which the beam passing through the control electrode 13 collides and emits light to display an image; 16a and 16b are containers, and 17a and 17b are line cathodes 11.
18 is a wire cathode 1 for positioning in the height direction.
1 is a spring that applies a load to stretch the wire cathode 11, and 19 is a fixing seat that fixes one end of the wire cathode 11. Both the spring 18 and the fixing seat 19 are fixed to insulating supports 12a and 12b.

In FIGS. 1 and 2, the back electrode 15 has a flat plate shape.
The protrusions 20 of this flat back electrode 15 have a structure in which protrusions 20a, 20b, 20c, and 20d are provided at the four corners, and the protrusions 20 are not bent or have screw holes.
Insulating support 1 corresponding to a, 20b, 20c, 20d
2a and 12b are provided with a notch 21, and a first 5-shaped metal fitting 22 is provided below the notch 21.
a and 22b are fixed by caulking or the like. In this state, the notches 21a, 21b of the insulating support 12aS12b,
Projections 20a, 20b, 2 of the back electrode are provided on 21c, 21d.
0c and 20d are inserted and positioned, and the first 5-shaped metal fitting 2 is inserted.
2a, 22b and the second L brackets 23a, 23b located above the notch 21 are fixed to the back electrode 15 by welding, so that the insulating supports 12a, 12b are positioned and fixed to the back electrode 15. become. In this state, one end of the wire cathode 11 is fixed to the spring 18, stretched by applying tension, and the other end is fixed to the fixing seat 19, thereby fixing the wire cathode 11. The image display device is completed by assembling the control electrode 13 and the like onto the assembled back electrode 15 and sealing it with the containers 16a and 16b. Here, insulators 17a and 17b are provided in contact with the back electrode 15, and the distance between the wire cathode 11 and the back electrode I5 or the control 4B electrode 13 is adjusted precisely by contacting the outer diameter of the insulators 17a and 17b. It will be well maintained. Furthermore, the first and second L-shaped fittings 23a and 23b can prevent the insulating supports 12a and 12b from tilting due to the tension of the wire cathode 11. The second L brackets 23a, 23b may or may not be fixed to the insulating supports 12a, 12b, and can be fixed with the first 5-shaped brackets 22a, 22b to reliably prevent tilting. If so, the second fixture 23a,
23b is not necessarily required.

Effects of the Invention As described above, in the present invention, the back electrode provided to emit electrons from the wire cathode is formed into a flat plate with a protrusion, and a metal fitting is cut into an insulating support to which a metal fitting is fixed in correspondence with the protrusion. A notch is provided, a protrusion is inserted into this notch, and the insulating support is connected to the back electrode through the metal fittings mentioned above.Since the back electrode is in the form of a flat plate, it can be bent without any bending part. It is easy to ensure flatness without worrying about distortion caused by the process, and the number of processing steps can be reduced. Furthermore, since it is a flat plate, it is possible to straighten multiple sheets at once during thermal straightening to improve flatness, and straightening to ensure accuracy is also easy. It becomes easy to secure the relative positions of the electrodes, and an image display device free from image defects such as uneven brightness can be provided.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an image display device according to an embodiment of the present invention, FIG. 2 is a perspective view of the same device, FIG. 3 is a sectional view showing a conventional image display device, and FIG. 4 is a main part thereof. It is an enlarged sectional view. 11... Line cathode, 12a, 12b...
Insulating support, 13... Control electrode, 14...
...phosphor, 15... back electrode, 20a, 20
b, 20c, 20 d--Protrusion, 22a, 22
b...L-shaped fitting.

Claims (1)

[Claims] An image display comprising a line cathode that emits electrons, a control electrode that controls the flow of the electrons, a phosphor that can receive the electrons and emit light, and a back electrode that is provided to cause the electrons to be emitted from the line cathode. In the device, the back electrode has a flat plate-like structure with a protrusion, has a notch into which the protrusion is inserted, an insulating support fixed to the back electrode, and an insulating support attached to the insulating support. An image display device characterized in that a metal fitting is fixed, and the insulating support body is bonded and fixed to a back electrode via the metal fitting.