JPS6158939B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a so-called in-line electron gun assembly in which electron gun elements are arranged side by side in a straight line, and particularly relates to an improvement in an in-line electron gun assembly having a partially integrated grid electrode. .

As shown in FIG. 1, an in-line electron gun assembly that uses both integrated and separate grid electrodes has third grid electrodes 4 and 5 and fourth grid electrode 6 integrated, and first grid electrode 2 and second grid electrode 6. Generally, the two grid electrodes 3 are of a separated type.

Next, the structure of the in-line electron gun assembly and the trajectory of the electron beam will be explained with reference to the drawings. That is, it consists of three cathodes 1, three first grid electrodes 2, three second grid electrodes 3, an integrated third grid electrode 4, 5, a fourth grid electrode 6, and a convergence electrode 7. The electron beam 9b emitted from the first grid electrode 2b, the second grid electrode 3b, the through holes 4b, 5b of the third grid electrodes 4, 5, and the through hole 6 of the fourth grid electrode 6
b and hits the face of the color cathode ray tube. Further, the electron beams 9a, 9c emitted from the cathodes 1a, 1c on both sides are the first grid electrodes 2a, 1c, respectively.
2c, the second grid electrodes 3a, 3c, the through holes 4a, 5a, 4c, 5c of the third grid electrodes 4, 5, and the fourth
It passes through the through holes 6a, 6c of the grid electrode 6, but in this case, the third grid electrodes 5a, 5c and the fourth grid electrode 6
It is deflected by the eccentricity between the axes provided between a and 6c, and converges with the central electron beam on the face or shadow mask of a color cathode ray tube.

The main electron lenses for electron beams on both sides formed between the third grating electrodes 5a, 5c and the fourth grating electrodes 6a, 6c decentered in this way, and between the third grating electrode 5b and the fourth grating electrode 6b which are not decentered. The central main electron lens for the electron beam is formed separately by the potential difference applied between the corresponding electrodes. Ideally, the electron beam that has passed through each main electron lens is directed to the face surface through a shadow mask, etc. When the electron beams collide with the electron beams, the beam spot should be circular, but in reality, the main electron lenses corresponding to each of the electron beams described above become non-circular due to interference between adjacent beam focusing electric fields. In order to reduce this non-circularity of the beam spot, the pairing of the third grid electrode 5 and the fourth grid electrode 6 is described in Japanese Patent Publication No. 4905 of 1972, which was published on February 8, 1978. At least one portion of the latter fourth grid electrode 6 is curved into a substantially cylindrical shape in a direction crossing the common plane of the electron beams, and has a concave surface with respect to the third grid electrode. is being considered.

However, even if we prevent interference between adjacent focused magnetic fields and form a nearly ideal electron lens, it is impossible to make the beam spot circular, so magnetic rings are used, but this is not possible. However, it has been extremely difficult to make the beam spot circular.

The present invention eliminates the above-mentioned drawbacks of the conventional electron gun assembly, obtains an ideal beam spot shape in an in-line electron gun assembly, and also provides a beam spot in the center and both sides at the corner of the face of a wide-angle color cathode ray tube. The purpose of the present invention is to provide a unitized in-line electron gun structure capable of concentrating an electron beam.

Next, one embodiment of the present invention will be described with reference to FIGS. 2 and 3.

That is, an in-line electron gun structure having an integrated grid electrode has a third grid electrode 15 as shown in FIG.
The fourth grid electrode 16 is integral, the first grid electrode 12 and the second grid electrode 13 are separate, and in this embodiment, the third grid electrode 15 and the fourth grid electrode 16 are integral. The four grid electrodes 16 are each formed of a perforated plate-like electrode structure having a plurality of electron beam passing holes, and further, for example, the third grid electrode 15
The size of the electron beam passage holes of the perforated plate-like electrode structures 15 ₁ , 15 ₂ , 15 ₃ is set to a desired value, and the plurality of perforated plate-like electrode structures 15 1 , 15 2 , 15 3 forming the fourth grid electrode 16 The structures 16 ₁ and 16 ₂ located near the extreme ends forming the main electron lens of the electrode structure are inclined at different angles near the apertures through which the electron beam passes on both sides.

Next, the locus of the electron beam in the in-line electron gun assembly having the above-described structure will be explained. That is, the three cathodes 11 are coated with red,
Three cathodes 11a, 11b, 1 that emit electron beams that impinge on fluorescent surfaces made of green, blue, and blue phosphors.
1c, and the electron beam emitted from, for example, 11b in each cathode is transmitted via the first grid electrode 12 and the second grid electrode 13 to the initial electrons of the third grid electrode 15, which is composed of a plurality of perforated plate electrode structures. A third electron beam passes through the beam passage hole 14b and further forms a main electron lens.
Electron beam passing hole 15b near the end of the grid electrode; electron beam passing hole 1 near the end of the fourth grid electrode 16;
6b and is projected onto the fluorescent surface 20 coated on the inner surface of the face via a convergence electrode (not shown). In this case, the trajectory of the electron beam 19b becomes a straight line passing through the axis of the electron gun when it is not deflected.

Next, the trajectories of the electron beams 19a and 19c on both sides will be described.To simplify the explanation, the cathode 11
The electron beam 19a emitted from a will be described in detail. That is, the electron beam emitted from the cathode 11a passes through the first grid electrode 12 and the second grid electrode 13 to the third grid electrode 15, which is made up of a plurality of perforated plate-shaped electrode structures.
The electron beam passing hole 15a near the end of the third grid electrode 15 that forms the main electron lens passes through the first electron beam passing hole 14a, and the fourth grid electrode 16
The electron beam passes through the electron beam passage hole 16a near the end of the
The electron beam passage holes of the perforated plate electrode structures 15 ₁ , 15 ₂ , 15 ₃ . . . forming the third grid electrode 16 are non-uniform as shown in FIG. Perforated plate electrode structures 16 ₁ , 16 ₂ forming the fourth pole electrode 16 opposite to the structure 15 ₁
are tilted at different angles, thereby forming a main electron lens with very good focus without interference from adjacent beam focusing electric fields, and furthermore at a desired angle with respect to the axis 19 parallel to the gun axis of the electron gun assembly. (about 1
20, such as a fluorescent surface or a shadow mask 20 shown in FIG. 2, so as to intersect with the electron beam 19b described above.

In the embodiment, the third grid electrode 15, the fourth
The grid electrode 16 also uses a perforated plate-like electrode structure, and the third
Although the perforated portion near the end of the grid electrode 15 is made non-uniform, and the inclined perforated plate electrode structure at the end edge of the fourth grid electrode 16 is made of two plates, the present invention is not limited to this. , at least one of the third grid electrode 15 and the fourth grid electrode 16 may be the conventional unitized electrode shown in FIG. It may also be a shaped electrode structure, or a combination thereof.
Various modifications are possible within the scope of the claims,
Furthermore, the electron beam passage hole is not limited to a circular shape, and depending on the shape, size, deflection angle, etc. of the color cathode ray tube, a part of it may be oval or oval, or a magnet or magnetic material may be attached. It is also possible to form the inline electron gun structure by using a spherical surface centered on the gun axis, and an in-line electron gun structure with a simple structure and very good characteristics can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view for explaining the structure of an example of a conventional in-line electron gun structure and the locus of an electron beam, and FIG. FIG. 3 is an enlarged cross-sectional view showing the trajectory of the electron beams on both sides in the vicinity of the main electron lens in FIG. 2 and the shape of the main electron lens. 1, 11... cathode, 2, 12... first grid electrode,
3, 13...Second grid electrode, 4,5,15...Third grid electrode, 6,16...Fourth grid electrode, 9b, 19b
...Trajectory of central electron beam, 9a, 9c, 19a,
19c...Trajectories of electron beams on both sides, 15 ₁ , 15
₂ , 15 ₃ , 16 ₁ , 16 ₂ , 16 ₃ ... perforated plate-like electrode structure.

Claims (1)

[Scope of Claims] 1. At least one pair of perforated electrode structures forming a main electron lens of an in-line electron gun structure for emitting electron beams at the center and both sides are arranged in-line.
At least one electrode located near the main electron lens of at least one of the perforated electrode structures is composed of a plurality of plate-shaped and/or shallow cap-shaped electrodes each having a plurality of electron beam passage holes, and at least one electrode is located near the main electron lens of at least one of the perforated electrode structures. 1. An in-line electron gun assembly, which is inclined in the vicinity of the beam passage hole, and a part of the electron beam passage hole of the electrode of at least one of the perforated electrode structures has a non-uniform circular shape. 2. Claim 1, characterized in that the slanted perforated electrode structure is made up of a plurality of plates, and the inclination is made to vary sequentially starting from the one located at the extreme end forming the main electron lens. The inline type electron gun structure described.