JPS6112331B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electron gun assembly used in a color picture tube. In general, the electron gun structures used in color picture tubes are arranged in delta type, in-line type, etc., and the main lens system is unipotential type,
Depending on the characteristics of each high-potential type,
The reality is that they are used differently. FIG. 1 is a partially cutaway elevational view showing a conventional in-line high-potential electron gun assembly for a color picture tube, and the electrode configuration (excluding the cathode) is a first control electrode 11, a second accelerating electrode 12, Third focusing electrode 1
3, 14, and a fourth focusing electrode 15. The electron beams emitted from the cathodes impinge on a fluorescent screen (not shown) through electron beam passage holes formed in each electrode. From the first control electrode 11 to the third focusing electrode 14, three electron beam passing holes are coaxially aligned along the tube axis, and at the fourth focusing electrode 15. In this case, the axes of the electron gun passage holes on both sides are slightly eccentrically located to the outside, and each of the electrodes is connected to an insulating glass rod 16.
It is welded and supported by. Due to the eccentricity, the third focusing electrodes 13 and 14 and the fourth focusing electrode 15 form a main electron lens, and the electron beams on both sides are focused on one hole point of a shadow mask (not shown). It is well known that this is being done. However, the third focusing electrode 1 as shown in FIG.
3 and 14 and the fourth focusing electrode 15 are integrated electrodes, the arrangement of the three electron beam passing holes by the integrated electrode causes electric field interference between the electron beams, reducing the spot shape of the electron beams and causing aberrations. Recently, as shown in Fig. 1, the outer protrusions of the third focusing electrode 14 and the fourth focusing electrode 15, which have respective electron beam passing holes (for red, green, and blue phosphor stimulation), have been developed. Cylinder 14a, 1 fitted and welded to the diameter
5a to prevent mutual electric field interference,
Structures have been developed that use means to minimize the occurrence of aberrations and improve image quality. The example of the conventional electron gun structure shown in Fig. 2 is
As shown in Japanese Patent No. 51-49875, the structure of the focusing electrode 24 includes metal flat plates 24a, 24b, 24c, 24d, 24e, and 24b, each having an electron beam passing hole.
4f and the second accelerating electrode 23 are similarly formed of metal flat plates, and an electron gun assembly including a cap-shaped first control electrode 22 and a cathode 21 is housed in the vacuum container 25, and is emitted from the cathode 21. The electron beam 29
It is configured to strike a fluorescent screen 26. The metal flat plates 24a, 24b, 24c, 24
A focusing electrode 24 consisting of metal plates 24a, 24c, 24f is used to form a periodic electric field.
and 24b, 24d, 24f are connected to the respective busbars 27, 28, and the metal flat plates 24a, 24
c, 24e connects the metal flat plate 24 to the _E1 power source.
b, 24d, and 24f are connected to the _E2 power source, respectively. If the E ₁ voltage and the E ₂ voltage are set to different constant voltages, a main electron lens with less aberration can be formed by obtaining a waveform periodic electric field within a range paraxial to the electron beam passage hole. However, the in-line color picture tube electron gun assembly 10 shown in FIG. 1 has the following drawbacks. That is, the third focusing electrodes 13 and 14 and the fourth focusing electrode 15
In both cases, due to deep drawing plastic working, the molecular structure of the internal crystal grain size of the plate-shaped material is not aligned, but after plastic working, the crystal grain size molecules change and become non-uniform, resulting in residual processing strain, Due to the structure change, the heat treatment temperature (800℃) due to the gas release treatment of the electrode structure
-1200°C), and during exhaust during the picture tube manufacturing process (temperature 435°C to 440°C), the shape changes significantly due to temperature, which is a factor that reduces the accuracy of the electrode structure. In addition, in order to prevent mutual interference due to electric fields near the electron beam passage holes of the opposing electrodes of the main lens forming part, that is, the third focusing electrode 14 and the fourth focusing electrode 15, and to reduce aberrations, the cylinders 14a and 15a are fitted and welded. Generation of deformation and residual strain when the third focusing electrode 1
3, 14, provided on the side wall of the fourth focusing electrode 15,
By welding the supporter 18 and welding the flange portions of the third focusing electrodes 13 and 14 to fix the supporter 18 by welding to the insulating glass rod 16 while leaving the deformation and residual strain of the supporter 18 intact during welding, Color picture tubes using such electron gun structures have the disadvantages of deterioration of the quality of each electrode, deterioration of related positional dimensions, that is, eccentricity between electrodes, parallelism errors, concentricity, bends, twists, and inclinations. The video quality was degraded. The present invention eliminates these drawbacks and achieves high precision and
The present invention provides a high-performance electron gun device for color picture tubes. Next, an embodiment of an electron gun assembly for a color picture tube according to the present invention will be described with reference to FIGS. 3 and 4. FIG. That is, the fourth focusing electrode that constitutes the electron gun structure 30
G ₄ ie 35 is 35a, 35b, 35c, third focusing electrode G ₃ is 34 is 34a, 34b, 34
c, second accelerating electrode G ₂ 33, first control electrode G ₁ 32
A first control electrode 31 is formed, and each of the electrodes is formed into a plate shape or a shallow cap shape. The feature of both is that electrodes with the same potential are formed for each set group. In the figure, 36 is an insulating glass rod. As mentioned above, each electrode part structure is a group of flat plate and shallow cap-shaped electrodes, and by configuring the same electrode by one or more electrodes, it is possible to improve the alignment of crystals of the material during plastic processing. Electrode parts are formed in a molecular structure state with particles, and do not leave any processing strain and prevent deformation at high temperatures such as heat treatment processes. In the experiment, the height of the shallow cap with 16% Cr-14% Ni and 0.40 tmm of stainless steel as the main component was 1.20.
In the range of ~2.0 mm, no machining strain was left and the crystal grain size and molecular structure did not change. Therefore, the reference planes of the electrode outer edge portions 41 and 42 shown in FIG. 4 are ensured, and mechanical and heat treatment precision is improved. As a reference between each electrode, see Figure 4 A and B.
A perspective view of a typical example is shown in Figure 2. To explain this in detail, the standard is a flat plate and a shallow cap 4 .
For both 0 and 50 , two outer edge portions 41 are formed on one side, which are parallel to the aa' line and the bb' line, which are distributed from the center points of the center holes 43a and 53a. In addition, the center hole 4 is arranged perpendicular to the a-a' line and the b-b' line.
c- distributed equally from the center point of 3a and 53a
Outer edge 4 of the midpoint where c' line and d-d' line are also parallel
2 is the reference point. The electrode arrangement of the electron gun structure (Fig. 3) 30 consists of two points on the outer edge 41 based on the a-a' line and one on the c-
One point on the outer edge 42 of line c' or line d-d', or b-
Two points on the outer edge 41 based on line b' and line c-c' or d
- It is composed of a total of three points arranged at right angles to one point on the outer edge 42 of the line d'. The main lens forming electrodes are a shallow cap type third focusing electrode 34c and a fourth focusing electrode 35 shown in the perspective view of FIG. 4B.
c to face each other. In this case, it is desirable that all the bent parts created by pressing etc. be curved so as not to cause mechanical strain, and since the supporter 44 part is welded to the insulating glass rod 36 at a distance from the opposing part, The distance between the two electrodes 34c and 35c due to foreign matter adhering to the surface of the insulating glass rod 36 is taken into consideration. The flat plate electrodes 34b, 35b are aligned with the electron beam passage holes of the electrodes 34c, 35c which form the crossover part of the main lens and the triode part, respectively.
A shallow cap electrode 3 is arranged regularly between a.
The electron gun assembly 30 is formed together with the electrodes 2 and 33, and it has been confirmed through experiments that in this case, it is desirable that the spacing between the interposed electrodes 35b and 34b be approximately 0.5 mm or less. That is, by setting the spacing to this level, it is possible to prevent stray electric fields from outside. By doing this, each electron beam passage hole becomes in a state where a stray electric field is virtually prevented through the cylinder, eliminating mutual interference of the electric fields of each electron beam (red, green, blue) and causing aberrations. I stopped waking up. As a feature of the configuration of the flat plate electrode and the shallow cap-shaped electrodes having the same potential as described above, the shallow cap-shaped electrodes at both ends, that is, the fourth focusing electrode 3 shown in FIG.
5, the flat plate electrodes 35 are interposed as shown in 35c and 35a, and the third focusing electrode 34 is shown as 34a and 34c.
b, 34b are arranged in a narrow shape, and the distance in the insulating glass rod 36 between each electrode (referring to the outside of the same potential electrode) is increased to prevent leakage between the electrodes and improve the withstand voltage characteristics. I can do it. The features and effects of the electron gun structure with the plate-shaped electrode and shallow cap configuration have been described above, but in FIG. Since it takes up more space than a diaphragm-processed part, it has become possible to form a large-diameter main electron lens with even fewer aberrations and better performance, thereby improving the image quality of a color picture tube. In the embodiment described above, the electrodes 34b, 3 interposed between the third focusing electrode 34 and the fourth focusing electrode 35
5b is a flat plate, but the present invention is not limited to this. For example, a shallow cap-shaped electrode or the edge of an electron beam passage hole as shown in FIG. It is also possible to make an electrode with a convex part only in the part (in the present invention, these are collectively referred to as an interpolated electrode),
Furthermore, lines (a-a') to (d-d') for reference
Of course, there are no particular limitations on the way the wires are taken, the shape of the supporter 44, etc.; Needless to say, it is also possible to arrange the electrodes so that they are in contact with each other at a desired position, for example, without providing a space between the electrodes.

[Brief explanation of the drawing]

Figure 1 is a partially cutaway elevational view of a conventional in-line electron gun assembly for color picture tubes, and Figure 2 shows the principle of aberration reduction when a conventional periodic electric field is formed and the focusing lens system is used as a plurality of electron lenses. Partially cut away elevation showing;
FIG. 3 is a longitudinal sectional view showing one embodiment of the electron gun assembly of the color picture tube of the present invention, and FIGS. 4a and 4b are perspective views showing the flat plate or shallow cap-shaped electrodes of FIG. 3. 10 , 30 ... Electron gun structure, 15, 35... Fourth focusing electrode, 14, 13, 34... Third focusing electrode, 1
2, 33... Second accelerating electrode, 11, 32... First limiting electrode, 34b, 35b... Interpolated electrode.

Claims (1)

[Claims] 1. At least two electrodes arranged opposite each other, each having a plurality of electron beam passage holes and forming an electron lens by supplying different potentials. An electron gun assembly characterized in that at least one of the plurality of electrodes is composed of a shallow cap-shaped electrode and an interposed electrode, and these electrodes are at the same potential. 2. The electron gun assembly according to claim 1, wherein the interposed electrode is a flat electrode. 3. The electron gun assembly according to claim 1, wherein the interposed electrode is made of a shallow cap shape processed to an extent that does not change the crystal grain size distribution and molecular arrangement structure of a plate-shaped material. 4. The electron gun assembly according to claims 1 to 3, wherein the interposed electrodes are arranged with a desired spacing from each other. 5. The electron gun assembly according to claims 1 to 3, wherein the interposed electrodes are arranged so as to be in contact with each other at desired positions.