JPS6070643A - Electron gun for picture tube - Google Patents

Abstract

PURPOSE:To reduce spherical aberration in a main lens system as well as to make the promotion of large caliber attainable, by housing a focusing electrode inside an accelerating electrode being set up inside a neck tube, while forming at least two sets of electron guns inside one accelerating electrode. CONSTITUTION:A electron gun 2 is housed inside a neck tube 1 and provided with a heater 5, a cathode 6, a first control grid 7, a first accelerating electrode 8, a second accelerating electrode 9 and a focusing electrode 10, while all electrodes but the electrode 10 are locked by bead glass 11. This electrode 10 is fixedly set up on an inner wall of the electrode 9 in a way of interposing, for example, an insulator 12 in between by means of shrinkage fit. Thus, electron lenses 13 and 14 are formed at both ends of the electrode 10. Therefore, a characteristic in a large-caliber electron gun is securable and simultaneously such a convergence characteristic as being excellent in stability is as well securable. In addition, a diameter in the neck tube 1 can be yet more thinned and, what is more, a power-saving aim and its miniaturization are well promotable.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an electron gun for cathode ray tubes, particularly for viewfinder tubes and cathode ray tubes for gloziection TVs.

This article relates to a single electron gun structure that can be applied to monochrome cathode ray tubes and other devices to obtain high resolution.

[Background of the invention]

Generally, in order to achieve high resolution in a cathode ray tube, it is effective to reduce the spherical aberration of the main lens system of the electron gun, and this can be achieved by increasing the aperture of the main lens system. Such 411 series 1, for example, JP-A-56-14
No. 46 and Japanese Utility Model Application No. 57-192049 disclose this method as a means for obtaining high snoring frequency.

However, there is always a need for high resolution, and in particular, ultra-high resolution cathode ray tubes, which have further improved resolution, are in demand due to recent trends in high-definition TVs.

[Purpose of the invention]

Therefore, the present invention has been made in view of the above-mentioned problems, and its purpose is to solve the following problems.

An object of the present invention is to provide an electron gun for a cathode ray tube in which the resolution of a 2-gun tube is further improved significantly.

[Summary of the invention]

In order to achieve such a purpose, unexploded EIIJ has a limit to the diameter of the main lens system that can be realized within the same neck diameter with a single electron gun, but by increasing the diameter by υ1 with a conventional electron gun. , Multi-stage focusing type■, Focusing on the fact that the secondary gun improves resolution by reducing the spherical aberration of the main lens system, skillfully combines the aforementioned large-diameter main lens system and multi-stage focusing type. This makes it possible to realize an electron gun with even higher tVt image resolution.

[Embodiments of the invention]

Next, embodiments of the present invention will be described in detail using the drawings.

FIG. 1 is a sectional view of essential parts showing an example of the configuration of an electron gun for a cathode ray tube according to the present invention. In the figure, an electron gun 2 is housed inside a neck tube 1 of a cathode ray tube, and this electron gun 2 is fixed concentrically on the tube axis of the neck tube 1 by a stem 3 and a pulp spacer contact 4. There is.

This electron gun 2 also has a heater 5. Cathode 6, 1st system ☆
ill grid T, 1st acceleration % pole 8. It has a second accelerating pole 9 and a focus electrode 10, and the electrodes other than the focus electrode 10 are fixed by bead glass 11.

In this case, the focus electrode 10 is fixedly disposed on the inner wall surface of the QP; There is.

In the electron gun constructed in this way, the operation of one rod at each station is almost the same as the conventional operation, but since the focus electrode 10 is housed inside the second accelerating electrode 9, Electron lenses 13, 14 are formed at both ends of the electrode 10. By appropriately setting the length of the focus electrode 1α in the tube axis direction, the electron lenses 13 and 14 can be made into a composite lens or a single lens.

Moreover, if the lens 13 and the lens 14 are used alone, a unipotential type multistage focusing lens system is formed.

This coupling, the second acceleration m pole9. The outer diameter of bead glass 1
Approximately 0.0 mm from the inner diameter of the L-neck tube 1 except for the part fixed with 1-.
5-1. In other words, a large diameter cylinder is used, and the outer diameter of the focus electrode 10 housed inside the cylinder is approximately 0.5 to 0.5 mm apart from the inner diameter of the second accelerating electrode 9. The dimensions shall be such that the distance is approximately 1.0. This dimension needs to be a dimension that takes into consideration the withstand voltage related to the potential of the focus electrode 10 and the potential of the second acceleration ↑L pole 9.

In such a configuration, in the past, only one set of electron lenses could be formed for those with small dimensions between the neck tube 1 and the second accelerating electrode 9;
By housing the focus electrode 10 inside, the diameter of the t02 acceleration corner l can be avoided by simply connecting a single lead wire that passes through a part of the second acceleration electrode. In addition, two sets of electron lenses 13 and 14 are installed at both ends of the focus electrode 100 without increasing the diameter of the neck tube 1.
It can be formed by a simple 4i&.

Therefore, with the above-mentioned modification, the characteristics of a large-diameter electron gun can be obtained, and the 7d lens 13, 1-
No effect on 4, 9, Color Gloziection T
In the case of 314 used as an electron gun for V, a highly stable convergence Iff property can be obtained. However, by using a five-piece gun that can be used in this manner, it is possible to reduce the diameter of the tube 1, and for example, the deflection force can be reduced.

118. How can high voltage be lowered? It has a power output of 51,9 and if applied to a viewfinder tube, it can be miniaturized.

FIG. 2 is a cross-sectional view of main parts showing another embodiment of the cathode ray tube electron gun according to the present invention. , is different from the first country in that a broken body 15 made of, for example, multiform glass (trade name manufactured by Asahi Glass Co., Ltd.) is interposed on the inner wall surface of the second accelerating electrode 9 by shrink fitting or the like.
Acceleration kg16 is arranged with its small diameter end fixed,
Furthermore, an insulator 1 is provided on the inner wall surface of this 81!3 accelerating electrode 16.
A focus electrode [10 is fixedly disposed via 2.

According to such a configuration, focus T+i, pole 1 (
1 is housed inside the third accelerating electrode 16, electron lenses 13 and 14 are formed at both ends of the focus electrode 10, and the small diameter of the third accelerating electrode 16 is housed inside the second accelerating electrode 9. Since the end "Ij" is housed, an electronic lens 1T is formed between the two ends. A total of three electronic lenses 13.14°17 are formed. By appropriately setting the length of the focus electrode 10 in the tube axis direction, the electron lenses 13, 14, and 17 can be made into two sets.

Even with such a structure of 41, the same effect as described above can be obtained.

〔Effect of the invention〕

As explained above, according to the present invention, by providing a focus electrode within the electron beam accelerating electrode, at least two sets of electron lens systems can be formed, whereas conventionally only one set of lenses could be formed with a large diameter. As a result, the main lens system's sphere n(1) aberration is reduced, making it possible to increase the aperture, and a so-called ultra-high fff N+ degree cathode ray tube with even higher resolution than conventional ones can be obtained with a simple configuration. It has an extremely excellent effect of being

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of the main part showing one embodiment of the 1111 electron gun for cathode ray tube according to the present invention, and FIG.
i is the upper tooth map. 1 @... Lee Tsuk tube, 2... Electron gun, 311...
・Stem, 4・・Valp spacer contact, 5+
1 @ analog heater, 6... Φ cathode, 7 fist... 1st
Control grid, 8...first linkage electrode, 9...second acceleration 11. Pole, 10...Focus 1o-Pole, 1
1... 9-pin glass, 12... Insulator, 13.
14...16, child lens, 15...φ insulator, 1
G...3rd acceleration 11 is the pole, 17, Φ conflict, electronic lens.

Claims (1)

[Claims] An electron gun for a cathode ray tube, in which a focus electrode is housed in an acceleration πi, 4i%i, arranged in a tube, and at least two sets of electron lenses are formed in - acceleration electrodes, which is 1jHf7%. .