KR930005828Y1 - Electron gun structure for color cathode-ray tube - Google Patents

Abstract

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Description

Electron Muzzle of the Color Chamber

1A and 1B show an electrode structure of a conventional electron gun, in which a is a plan view of the main lens electrode, and b is a front sectional view of the main lens electrode.

2A and 2B show a group of equipotential lines formed by FIG. 1, a is a cross sectional view of a main lens electrode showing a group of equipotential lines on a horizontal plane, and b is a cross sectional view of a main lens electrode showing a coin phase group on a vertical plane.

3 is a perspective view of a conventional main lens electrode in which the main lens electrode of FIG. 1 is improved.

4 is a perspective view of the main lens electrode of the present invention.

5 is an exploded perspective view of FIG.

6 is a cross-sectional view showing an equipotential line on a horizontal plane formed by FIG.

* Explanation of symbols for main parts of the drawings

3: plate type electrode element 4: cap type electrode element

5: electrode body 31R, 31G, 31B: opening

33: gap 41: opening

50R, 50G, 50B: axis of electron gun

The present invention relates to the electron barrel of the color receiver, and more particularly, to the electron barrel of the color receiver, which has improved astigmatism by improving the main lens electrode structure.

In general, the resolution of the electron gun of the color receiver is limited by the spherical aberration. In order to obtain high resolution, the diameter of the main lens electrode is made as large as possible to reduce the spherical aberration of the main lens. In the case of in-line color water pipes, 30% of the internal diameter of the neck tube is the maximum of the main lens electrode diameter.

1A and 1B show a conventional main lens electrode sphere formed by the above method, wherein the electrode sphere 1 is formed at the center 10R of both side openings 11R and 11B at the center 10G of the center opening 11G. 10B) is separated by a distance S, and each opening 11R, 11G, 11B is reinforced with a cylindrical bar ring 14 having a height h on the upper surface portion 12 of the electrode sphere 1, and each opening. The diameter D of 11R, 11G, 11B is large-diameterized so that the space | interval part between each opening 11R, 11G, 11B may become twice the thickness of the electrode sphere 1.

2A and 2B show the other electrode sphere 1 'having the same structure as the electrode sphere 1 on the same side 10R, 10G, 10B of each opening 11R, 11G, 11B. In Fig. 1, the high voltage and the low electrode voltage are applied to the electrode sphere 1 ', and the coincidence lines of the main lens formed in the cross section of the electrode sphere 1 are shown, where 16, 16', 17, and 17 'are respectively. Equipotential group.

As shown in FIG. 2A, on the opposite side of the electrode sphere 1 (1 '), an independent electrostatic lens is formed for each of the openings 11R, 11C, and 11B through which the respective electron beams pass, and the inside of the electrode sphere 1, 1' is formed. In the case of the electrostatic lens group 16 and 16 'constituting the electrostatic lens, the common equipotential lines are not used for each opening, and the curvature of the electrostatic lens of the center openings 11G and 11G' is double outer opening 11R. , 11B) is less hostile than (11R ', 11B).

Therefore, the electrostatic lens formed in the center openings 11G and 11G 'is weaker than the electrostatic lenses formed in the openings 11R and 11B (11R' and 11B ') on both sides, and the electron beam in this cross section (horizontal line) is the central electron beam. The diameter becomes larger than the two outer electron beam diameters.

Also, FIG. 2b shows a group of medium potential lines 17, 17 'formed in the vertical section of the central opening 11G, 11G' of FIG. A, and each opening 11R, 11R ', 11G, and 11G'. (11B) and (11B ') are symmetrical and independent electrostatic lenses of substantially the same intensity, respectively, and the curvature of the equipotential line groups 17, 17' is greater than the curvature of the equipotential line groups 16, 16 '. The electron beam in the vertical plane is smaller than the electron beam in the horizontal plane.

Therefore, the above-mentioned electrostatic lens has a drawback that the astigmatism increases due to the difference in curvature of the equipotential line group in the horizontal vertical plane.

Conventionally, the above-mentioned problem has been solved, such as Japanese Patent Laid-Open No. 58-206030. The above-described design of the electrode sphere 2 is similar to that of the above-described electrode sphere 1 as shown in FIG. Openings 21R, 21G, 21B, which are three electron beam passing through, are formed in the upper surface portion 22 on the axes 20R, 20G, and 20B of the three electron guns whose spacing S is maintained in the open space. ), The gap 23 formed between the opening 21G and the opening 21G and the opening 21B is narrowed to about twice the thickness of the electrode sphere 2 forming member so that the aperture of each opening 21R, 21G, 21B is narrowed. As much as possible, the baring portion 24 is protruded into the electrode sphere 2.

Therefore, the gap 23 formed in the open space protrudes into the electrode and is retracted by the distance d from the upper surface portion 22 to form a concave depression.

In this structure, since the spaced portion 23 forms a recessed portion with respect to the upper surface portion 22, the equipotential line group of the main lens does not pass through the openings 21R, 21G, 21B in the cross section including three electron gun axes. Since the occurrence of equipotential lines is suppressed to the minimum, the same electrostatic lens is formed, so that the intensity of each electrostatic lens in the horizontal plane is almost the same, and the difference in curvature of the electrostatic lens is also minimized, thereby obtaining a beam spot with minimized astigmatism. Will be.

However, in order to maximize the diameter of the opening through which the electron beam passes during the electrode manufacturing, the space 23 of the adjacent opening space is supported by about two sheets of the plate thickness constituting the electrode, and the non-ring portion around the opening ( 24) is formed by concave depressions in the gap 23 after the protrusion is formed inwardly so that mechanical deformation easily occurs, and deformation may easily occur due to the pressure applied to the electrode when assembling the electron gun. As a result, the operation of the electron gun is the main cause of the change in focus characteristics.

The present invention has been made to solve the above problems, and as described in detail with reference to FIGS. 5 and 6 to increase the mechanical strength by separating and molding the electrode sphere, the main lens electrode 5 of the present invention is a plate-shaped electrode element (3) and the cap-shaped electrode element (4), which is formed by separating between the opening 31R and the opening 31G of the upper surface portion 32 of the plate-shaped electrode element 3, and between the opening 31G and the opening 31B. The spacing portion 33 was formed by extruding a plate member having a predetermined thickness (for example, 2-4 mm) so as to form a recessed portion retreating by a predetermined distance d from the upper surface portion.

In addition, the cap-shaped electrode element 4 is provided with a race track opening 41 in the upper surface portion 42. The length in the lateral direction of the opening 41 is L and the width in the longitudinal direction is T, The length in each of the openings 31R, 31G, and 31B of the electrode element 3 in the inline direction is referred to as L, and when the width in the vertical direction is referred to as t, each of L <L, t <T.

The electrode sphere 5 of the main lens electrode separately formed into the plate-shaped electrode element 3 and the cap-shaped electrode element 4 as described above is formed on the upper surface portion 42 of the cap-shaped electrode element 4. The effect is as shown in Figure 6.

That is, the electrode sphere 5 'having the same structure as that of the electrode sphere 5 is disposed opposite to the electrode sphere 5 so that a high voltage is applied to the electrode sphere 5 and a low voltage to the electrode sphere 5' as usual. Is applied, the equipotential line group 54, 54 of the main electrostatic lens in the cross section including the three electron guns 50R, 50G, 50B by the concave depressions of the gaps 33, 33 'as shown in FIG. ') Suppresses the generation of equipotential lines not passing through the respective openings 31R, 31G, 31B, and 31R', 31G ', 31B', thereby forming almost the same electrostatic lens.

Therefore, each of the electrostatic lens intensities in the horizontal plane is almost the same, and the curvature difference between the electrostatic lenses in the horizontal plane and the vertical plane in which the respective openings are arranged is minimized, thereby obtaining a beam spot without astigmatism.

As described above, the present invention is made by separating the main lens electrode from the plate-shaped electrode element and the cup-type electronic element, and then attaching the main lens electrode to each other, so that the mechanical strength is increased so that there is no fear of deformation even in the pressure applied during the assembly of the electron gun. There is no focus fluctuation, and its manufacture is also very easy, which is a very useful design suitable for high quality mass production.

Claims (4)

In the electron gun electrode sphere in which three holes through which three electron beams pass are formed in an inline shape, and recesses are formed in the inner surface of the electrode, the main lens electrode is separated into a plate electrode element 3 and a cap electrode element 4. An electron muzzle of a color receiver. 2. The plate-shaped electrode element 3 has a thickness of 2-4 [mm], the recessed portion formed by the inner surface of the electrode of the gaps 33R, 31G, and 31B adjacent to each other. The electron muzzle of the color receiver. The electron muzzle of the color receiver as claimed in claim 1, characterized in that the cap-shaped electrode element (4) is provided with a race track opening (41) in the upper surface portion (42). 4. The length in the transverse direction of the openings 41 is L and the width in the longitudinal direction is T, and the lengths of the openings 31R, 31G, 31B in the in-line direction are defined in Claims 2 and 3. [1] Each of the apertures 31r, 31g, and 31b is formed such that L &lt; L and t &lt; T when the width in the vertical direction is t.