JP3130554B2 - Color picture tube - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[Object of the Invention]

[0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color picture tube, and more particularly to a magnetic picture tube having a magnetic material attached to an electron gun and magnetized from outside the neck to obtain static convergence and color purity on a phosphor screen. The present invention relates to a color picture tube for adjusting the image quality.

[0003]

2. Description of the Related Art Generally, a color picture tube has an envelope comprising a panel 1 and a funnel 2 integrally joined to the panel 1, as shown in FIG. Emitted from the electron gun 4 disposed in the
The electron beams 5B, 5G, and 5R are deflected by a magnetic field generated by a deflection yoke 6 mounted outside the funnel 2, and formed on the inner surface of the panel 1 via a shadow mask 7 disposed inside the panel 1. By horizontally and vertically scanning the phosphor screen 8 thus set, the phosphor screen 8 is scanned.
It has a structure for displaying a color image thereon.

In order to improve the quality of a color image drawn on the phosphor screen 8, the three electron beams 5B, 5G, 5R emitted from the electron gun 4 are concentrated on one point on the phosphor screen 8 ( (Static convergence), and the three electron beams 5B, 5G, and 5R must properly land the three-color phosphor layers constituting the phosphor screen 8 to obtain a predetermined color purity. However, the actually manufactured color picture tube has three electron beams 5B and 3B due to an assembly error of the electron gun 4 and an assembly error of the color picture tube itself.
5G, 5R concentration and 3 electron beam 5B for 3 color phosphor layer
The landing of 5G and 5R shifts, and the screen quality deteriorates.

[0005] Therefore, a magnet is attached to an ordinary color picture tube in order to correct static convergence and landing deviation. In the color picture tube shown in FIG. 6A, the magnet 9 is mounted outside the neck 3.
Usually, this magnet 9 has two poles, four poles along the periphery of the annular magnetic body.
It consists of three sets of permanent magnets, one set of two magnets forming poles and six poles. Each set of magnets is rotated to appropriately shift the set of two magnetic poles in the circumferential direction, thereby achieving static. It adjusts convergence and color purity.

However, the adjustment of static convergence and color purity using three sets of permanent magnets, one set of which is two magnets, requires not only skill but a considerable amount of time for adjustment, and adjustment work is difficult. It is difficult to make accurate and sufficient adjustments.

To compensate for the problem caused by the external magnet, Japanese Patent Application Laid-Open Nos. Sho 52-117512 and
No. 8235, U.S. Pat. No. 4,162,470 and U.S. Pat. No. 4,138,628, include:
As shown in FIG. 6B, the outer peripheral surface of the electrode of the electron gun 4 is
At least one magnetizable ring-shaped magnetic body 11 is attached, and the ring-shaped magnetic body 11 is polarized from outside the neck 3 to two poles, four poles, six poles, twelve poles, and the like. Are shown for adjusting the color picture tube.

[0008] In the mounting method <br/> of the magnetic body 11 of the color picture tube, as shown in FIG. 7 (a), a method of attaching by welding a metal strip 13 on the outer peripheral surface of the electrode 12, the ( As shown by point 14 in b), there is a method in which the magnetic body 11 is directly welded to the outer peripheral surface of the electrode 12.

By the way, in order to adjust the static convergence and the color purity with higher accuracy, the magnetic body 11 must be perpendicular to the tube axis (Z axis) (the traveling direction of the electron beam). (B) When the magnetic material attached to the electrodes approaches the inner surface of the neck, a spark discharge occurs between the magnetic material and the inner surface of the neck during operation of the color picture tube, driving the color picture tube. Due to the destruction of the circuit or the spark discharge, the magnetization characteristics of the magnetized magnet change to optimally correct static convergence and color purity, and the adjustment of static convergence and color purity becomes insufficient For this reason, it is necessary to mount as far as possible from the inner surface of the neck.

[0010]

As described above, in order to adjust the static convergence and color purity of a color picture tube,
At least one magnetizable annular magnetic body is attached to the outer peripheral surface of the electrode of the electron gun, and this annular magnetic body is attached to two poles,
There is a color picture tube which is polarized and magnetized to a pole, 6 pole, 12 pole, or the like. As a method of attaching the magnetic body, a method of welding a metal piece to the outer peripheral surface of the electrode and attaching it,
There is a method such as welding the magnetic material directly to the outer peripheral surface of the electrode.However, regardless of the method used, the magnetic material should be placed on a plane perpendicular to the tube axis, and the neck should be as small as possible to prevent spark discharge. It is necessary to mount it away from the inner surface.

However, in the method of attaching the above metal pieces by welding, it is difficult to accurately arrange the magnetic material on a plane perpendicular to the tube axis.
Since the metal piece approaches the inner surface of the neck, spark discharge easily occurs. Further, there is a problem that a metal piece for attaching a magnetic body is required. On the other hand, the method of directly welding the magnetic material to the outer peripheral surface of the electrode is also difficult to accurately arrange on a plane perpendicular to the tube axis, and depending on the shape of the magnetic material, many spot welding is required, There is a problem that it affects the magnetization characteristics of the magnetic field. Further, regardless of the method of attachment, the magnetic body is located on the outer peripheral surface of the electrode, so that it can easily approach the inner surface of the neck. In particular, when the outer diameter of the electrode is larger than the inner diameter of the neck, it becomes impossible to arrange the magnetic material.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems. When a magnetic material is attached to an electrode of an electron gun, the magnetic material is easily placed on a tube axis, that is, a plane perpendicular to the traveling direction of an electron beam. It is an object of the invention to configure a color picture tube so that it can be arranged and can be positioned away from the inner surface of the neck.

[Structure of the Invention]

[0014]

An electron gun comprising a cathode and a plurality of electrodes arranged sequentially adjacent to the cathode is disposed in a neck, and at least one magnetizable electrode is provided on a predetermined electrode of the electron gun. Is mounted,
In a color picture tube for magnetizing this magnetic material and correcting the trajectory of an electron beam emitted from the electron gun, the predetermined electrode is constituted by a plurality of divided electrodes located adjacent to each other in the tube axis direction, A magnetic material was inserted in the gap between the separated electrodes arranged apart .

[0015]

As described above, the electrode for mounting the magnetic body is constituted by a plurality of divided electrodes located adjacent to each other in the tube axis direction.
When a magnetic material is inserted in the gap between the split electrodes that are spaced apart , the magnetic material can be easily placed on a plane perpendicular to the tube axis, and divided by the minimum number of welding points so as not to affect the magnetization characteristics Can be fixed between electrodes. In addition, it is possible to arrange the magnetic body away from the inner surface of the neck . On the other hand, by approaching the trajectory of the electron beam, the trajectory of the electron beam can be corrected with high accuracy with a smaller magnetic field. In addition, magnetic material
There is nothing between the magnetic body and the magnetizing device when magnetizing
Therefore, the magnetic material can be efficiently magnetized,
Since there is nothing between the magnetic material and the electron beam,
The trajectory of the electron beam can be corrected efficiently.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings based on embodiments.

FIG. 1 shows a color picture tube according to an embodiment of the present invention. This color picture tube has a panel 1 and an envelope composed of a funnel 2 integrally joined to the panel 1, and a shadow mask 7 provided inside the panel 1 and having a large number of electron beam passage holes formed therein. A phosphor screen 8 formed of a three-color phosphor layer that emits blue, green, and red light is formed on the inner surface of the panel 1 so as to face the panel. An electron gun 20 is provided in the neck 3 of the funnel 2. Note that 6
Is a deflection yoke mounted outside the funnel 2.

The electron gun 20 is an in-line type electron gun which emits three electron beams 22G, 22B and 22R arranged in a line composed of a center beam 22G and a pair of side beams 22B and 22R passing on the same horizontal plane. , Three cathodes K arranged in a line (only one cathode K is shown in the drawing),
Three heaters H for individually heating the cathodes K, and first to sixth heaters H arranged on the cathodes K at predetermined intervals in the direction of the phosphor screen along the tube axis (Z axis).
It comprises grids G1-G6 and a convergence cup C mounted on its sixth grid G6. The first to third grids G1 to G3 are each formed of a horizontally long elliptical plate-like electrode, and the fourth to sixth grids G4 to G6 are each formed of a horizontally long elliptical cylindrical electrode. Electrodes, each of which has the three cathodes K
, Three electron beam passage holes are formed in a row in the horizontal direction.

In particular, the fifth grid G5 of the electron gun 20 has four cup-shaped divided electrodes G51 to G54 adjacent in the tube axis direction.
The divided electrodes G52 and G53 are spaced apart from each other as shown in FIG.
Annular magnetic body 24 shown in FIG. 4 the catcher-up 25 is inserted. That is, the elliptical divided electrode G5, which is long in the horizontal direction,
2 and G53, the magnetic body 24 has its divided electrodes G52 and G53.
Is formed in an annular shape having an outer diameter substantially equal to the horizontal major diameter of the two electrodes G52, G53. The two divided electrodes G52, G53 are sandwiched by both ends in the horizontal direction. It is welded to the split electrodes G52 and G53. The inner diameter of the magnetic body 24 is equal to the diameter of the divided electrode G52 as described above.
, When placed between G53, the divided electrodes G52, G53
It does not block the electron beam passing through the inside.

The magnetic body 24 is attached in advance when assembling the electron gun, and the electron gun is sealed in a neck and evacuated to produce a color picture tube. A magnetic pole necessary for correcting convergence deviation and color purity is formed.

By the way, the predetermined electrode on which the magnetic body 24 is to be arranged as described above is constituted by a plurality of divided electrodes adjacent in the tube axis direction, and the magnetic body 24 is placed in the gap between the spaced apart divided electrodes. With the interposition, the magnetic body 24 can be accurately and easily arranged in a plane orthogonal to the traveling direction of the electron beams 22G, 22B, and 22R . Moreover, since the magnetic body 24 can be securely fixed with the minimum number of welding points, the static convergence and color purity of the three electron beams 22G, 22B and 22R can be accurately corrected without changing the magnetization characteristics of the magnetic body 24. it can. Also, compared to the conventional arrangement of magnetic materials, the electron beam
G, 22B, and 22R can be positioned close to each other, so that static convergence and color purity can be adjusted with a smaller magnetic field. Is less likely to occur. In addition, when magnetizing a magnetic material,
Because there is nothing between the body and the magnetizing device,
Can be performed efficiently. In addition, magnetic materials and electronic
Since there is nothing between the
Trajectory can be corrected.

In the above-described embodiment, the magnetic body is formed in an annular shape. However, as shown in FIG. 5, the magnetic body 24 forms an electron beam such as an elliptical shape approximate to a divided electrode sandwiching the magnetic body. It may be formed in other shapes that do not block. The magnetic body does not necessarily have to have a circular cross section, but may have another shape such as a plate shape.

In the above-described embodiment, a case has been described in which one magnetic body is interposed between the divided electrodes. However, a plurality of magnetic bodies may be interposed between the divided electrodes. In addition, it can be fixed not only between the divided electrodes but also on one of the adjacent electrodes having a potential difference and arranged between the adjacent electrodes.

Further, in the above embodiment, the case where the static convergence and the color purity are adjusted has been described. However, the present invention is not limited to the adjustment of the static convergence and the color purity, but also the correction of the aberration caused by the axial deviation of the electron beam. In short, it can be used for correcting the trajectory of an electron beam.

[0025]

A color picture tube for attaching at least one magnetizable annular magnetic body to a predetermined electrode of an electron gun and magnetizing the magnetic body to correct the trajectory of an electron beam emitted from the electron gun. in, composed of a plurality of divided electrodes located adjacent the predetermined electrodes in the tube axis direction, the spaced arrangement
When a magnetic material is inserted in the gap between the placed split electrodes,
The magnetic material can be accurately and easily placed on a plane perpendicular to the direction of electron beam travel, and can be fixed between the split electrodes with a minimum number of welding points so as not to affect the magnetization characteristics, such as static convergence and color purity. Can be accurately corrected. In addition, by bringing the magnetic material close to the trajectory of the electron beam, the trajectory of the electron beam can be corrected with a smaller magnetic field .
In addition, by disposing the magnetic body away from the inner surface of the neck, it is possible to make it difficult to generate a spark during the operation of the color picture tube. In addition, when magnetizing a magnetic material,
Since there is nothing between the magnetizers, the magnetization of the magnetic material is efficient
Can do well. In addition, magnetic material and electron beam
Since there is nothing in between, the trajectory of the electron beam is efficiently
Can be corrected. Less than
Up

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a color picture tube according to an embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of an electron gun to which the magnetic body is attached.

FIG. 3 is a perspective view for explaining a divided electrode to which a magnetic body of the electron gun is attached.

FIG. 4 is a perspective view of a magnetic body attached to the split electrode.

FIG. 5 is a perspective view of magnetic bodies having different shapes.

FIG. 6 is a diagram showing a configuration of a conventional color picture tube,
FIG. 6A is a configuration diagram of a color picture tube in which a magnet for adjusting static convergence and color purity is mounted outside the neck, FIG.
(B) is a configuration diagram of a color picture tube in which a magnetic material is arranged in a neck.

FIGS. 7A and 7B are diagrams showing a method of attaching the magnetic body.

[Explanation of symbols]

 2 Funnel 3 Neck 8 Phosphor screen 20 Electron gun 24 Magnetic substance H Heater G1 First grid G2 Second grid G3 Third grid G4 Fourth grid G5 Fifth grid G6 6 grids G51 to G54: split electrode K: cathode

Claims (1)

(57) [Claims] 1. An electron gun comprising a cathode and a plurality of electrodes arranged adjacently to the cathode in a neck, and at least one magnetizable annular magnetic body is provided on a predetermined electrode of the electron gun. A color picture tube for magnetizing the magnetic material and correcting the trajectory of the electron beam emitted from the electron gun, wherein the predetermined electrode is a plurality of divided electrodes located adjacent to each other in the tube axis direction. Between the divided electrodes that are spaced apart from each other.
A color picture tube, wherein the magnetic material is inserted in a cap .