JPH08203451A - Deflecting apparatus for color picture tube - Google Patents

Abstract

PURPOSE: To provide a deflecting apparatus with which a deflecting magnetic field with desiring distribution can easily be obtained by setting a coil which deflects electron beam in the direction of a manor axis of a screen in the way the coil overlaps the inside of a coil which deflects electron beam in the direction of the major axis. CONSTITUTION: Regarding a deflecting apparatus for a color picture tube, a first deflecting coil 21H to deflect electron beam emitted out of an electron gun in the direction of a major axis of a screen and a second deflecting coil 21V to deflect electron beam in the direction of a minor axis of the screen are so bent toward outside in bridging line parts in rear end parts as to form bent parts 22H, 23H, 22V, 23V and form a saddle-like shape. In this case, the coil 21V is positioned in the inside of the coil 21H and these coils are so set as to be partly overlapped each other. Consequently, the deflecting magnetic field generated by the coil 21V can optionally be extended toward the rear part where an electron gun exists and magnetic fields with different distribution depending on color picture tubes can easily be formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deflector for a color picture tube, and more particularly to a deflector for a color picture tube which is effective for an in-line type color picture tube which emits three electron beams arranged in a row passing through the same plane.

[0002]

2. Description of the Related Art Generally, a color picture tube has an envelope composed of a panel 1 and a funnel-shaped funnel 2 joined to the panel 1, as shown in FIG. A phosphor screen 3 including a three-color phosphor layer that emits green, red, and red is provided, and a shadow mask 4 is disposed inside the phosphor screen 3 so as to face the phosphor screen 3. On the other hand, in the neck 5 of the funnel 2, 3 electron beams 6B
, 6G, 6R emitting electron gun 7 is provided.
And the three electron beam 6B emitted from this electron gun 7
, 6G, 6R are deflected by the magnetic field generated by the deflecting device 9 mounted outside the boundary between the large-diameter portion 8 and the neck 5 of the funnel 2 to scan the phosphor screen 3 horizontally and vertically. , A structure for displaying a color image.

The deflecting device 9 generally comprises a three-electron beam 6
A horizontal deflection coil 11 that generates a horizontal deflection magnetic field that horizontally deflects B, 6G, and 6R, and three electron beams 6B and 6G
, 6R in the vertical direction, and a vertical deflection coil 12 for generating a vertical deflection magnetic field.

In such a color picture tube, the electron guns 7 are arranged in a row so as to pass the electron guns 7 in a row.
An in-line type electron gun which emits B, 6G and 6R, and three electron beams 6B, 6G and 6R emitted from this electron gun
Is deflected by a horizontal deflection magnetic field having a pincushion type magnetic flux density distribution generated by the horizontal deflection coil 11 of the deflecting device 9 and a vertical deflection magnetic field having a barrel type magnetic flux density distribution generated by the vertical deflection coil 12, thereby generating a three electron beam 6B. , 6G, 6R
A self-convergence in-line type color picture tube that concentrates the light on the phosphor screen 3 is widely used.

Generally, in a color picture tube, in order to display a good quality image on the phosphor screen 3, the three electron beams 6B, 6G and 6R emitted from the electron gun 7 are concentrated over the entire screen (dynamic convergence). However, in the self-convergence in-line type color picture tube, it is possible to display an image without convergence deviation due to the magnetic field generated by the deflecting device 9 without providing a dynamic convergence correction circuit in the receiver. Is. At the same time, the horizontal deflection magnetic field of the pincushion type magnetic flux density distribution can prevent geometrical distortion from occurring in the upper and lower parts of the raster, so that there is an advantage that the correction circuit can be eliminated.

However, as shown in FIG. 4, the horizontal deflection magnetic field 1
If 4H is a magnetic field having a pincushion type magnetic flux density distribution over its entire area and a vertical deflection magnetic field of 14V is a magnetic field having a barrel type magnetic flux density distribution over its entire area, then (a) vertical deflection causes geometric distortion to the left and right of the raster. (B) Among the three electron beams arranged in a line, there is a problem that a coma error occurs between the center beam and the pair of side beams.

Therefore, regarding the horizontal and vertical deflection magnetic fields,
As shown in FIG. 5, as a distribution of the deflection magnetic field which can secure the geometric distortion and dynamic convergence of the raster and solve the above-mentioned problem, as shown in FIG. 5, the horizontal deflection magnetic field 14H is at the rear side (neck side) of the deflection device. Barrel-shaped, the front side (larger side of the funnel) has a pin-cushion type, and the vertical deflection magnetic field of 14 V should be a pin-cushion type magnetic field at the rear side and a barrel-shaped magnetic field at the front side. Are known. The pincushion-shaped and barrel-shaped magnetic field distributions and occupying ratios differ depending on the picture tube system.

Such a deflection magnetic field can be formed by a saddle type deflection coil for both horizontal and vertical deflection magnetic fields.
In the conventional deflection device, a horizontal deflection coil is formed outside the separator and a vertical deflection coil is arranged inside the separator with the separator interposed therebetween. This saddle type deflection coil
Bend portions bent outward are formed on the connecting line portions at the front end portion and the rear end portion, respectively. This bend portion shortens the entire length of the deflecting device, and contributes to downsizing of the deflecting device.

[0009]

As described above, conventionally, the electron gun is an electron gun that emits three electron beams arranged in a row passing through the same horizontal plane, and the three electron beams emitted from this electron gun are deflected. The electron beam is concentrated on the phosphor screen by deflecting with the horizontal deflection magnetic field of the pincushion type magnetic flux density distribution generated by the horizontal deflection coil of the device and the vertical deflection magnetic field of the barrel type magnetic flux density distribution generated by the vertical deflection coil. Self-convergence in-line type color picture tubes are widely used.

As the magnetic field generated by the deflecting device, a horizontal deflecting magnetic field is barrel-shaped on the rear side of the deflecting device.
It is known that the pincushion shape is formed on the front side, and the vertical deflection magnetic field may be formed to have a pincushion shape on the rear side and a barrel shape on the front side. Such a deflection magnetic field can be formed by a saddle type deflection coil for both the horizontal and vertical deflection magnetic fields. In the conventional deflection device, a horizontal deflection coil is provided outside with a separator interposed therebetween.
It is formed in a structure in which a vertical deflection coil is arranged inside thereof.

However, such a saddle / saddle type deflection device comprising both horizontal and vertical deflection coils and a saddle type deflection coil causes the screen to become larger as the color picture tube becomes larger, flatter, thinner and the deflection angle becomes wider. The difference between the distance to the center of the and the distance to the periphery becomes large, making it difficult for the self-convergence to concentrate the three electron beams arranged in a row over the entire screen, and at the same time, the focusing characteristics deteriorate,
This causes deterioration of image quality.

The present invention has been made in view of the above problems, and a deflection magnetic field having a desired distribution can be easily obtained regardless of the enlargement, flattening, thinning of a color picture tube, and enlargement of the deflection angle. It is intended to configure the deflection device so that

[0013]

A first deflection coil for deflecting an electron beam emitted from an electron gun of a color picture tube in the major axis direction of the screen and a second deflection coil for deflecting the electron beam in the minor axis direction of the screen. Is a saddle type in which a bend part is formed by bending the outside to a crossover part of the rear end part, and the first and second deflection coils are arranged so that at least a part of them overlap each other. In the deflection device, the second deflection coil is located inside the first deflection coil.

Further, the rear portion of the second deflection coil has a structure protruding rearward of the rear end portion of the first deflection coil.

[0015]

As described above, both the first deflection coil for deflecting the electron beam in the major axis direction of the screen and the second deflection coil for deflecting the electron beam in the minor axis direction are formed in the saddle type, and the second deflection coil is When it is located inside one deflection coil, the deflection magnetic field generated by the second deflection coil that deflects the electron beam in the short axis direction of the screen can be arbitrarily extended in the rear direction where the electron gun is located. Magnetic fields having different distributions can be easily formed.

[0016]

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

FIG. 1 shows an in-line type color picture tube deflecting device, which is an embodiment thereof. This deflecting device is composed of a substantially trapezoidal separator 20 made of synthetic resin, and a pair of saddle-type horizontal deflection coils 21H (first deflection) which are vertically symmetrically arranged on the outer side of the separator 20 with a horizontal axis (X axis) interposed therebetween. Coil) and the vertical axis (Y
Axis) and a pair of saddle-type vertical deflection coils 21v (second deflection coils) symmetrically arranged, and a hollow trapezoidal core 24 made of a magnetic substance and arranged outside the horizontal deflection coil 21H. Has been done. The horizontal and vertical deflection coils 21H and 21v have bend portions 22H and 2B that are bent outward, respectively, at the crossover portions at the front and rear ends.
3H, 22V and 23V are formed, and the core 24 is arranged so as to surround the bend portions 22H and 23H formed on the connecting line portions of the front end portion and the rear end portion of the horizontal deflection coil 21H. The rear part (neck side of the color picture tube) of the pair of saddle type vertical deflection coils 21v projects rearward of the rear part of the horizontal deflection coil 21H.

When the deflecting device is constructed as described above, FIG.
The deflection magnetic field shown in is formed. That is, as shown in FIG. 2A, a pair of saddle type horizontal deflection coils are barrel-shaped on the rear side of the deflecting device, like the magnetic field generated by a conventional horizontal deflection coil (see FIG. 5A). When a pincushion-shaped magnetic field 26H is generated on the front side (on the large-diameter side of the funnel of the color picture tube), as shown in FIG. The rear side has a pincushion type, the front side has a barrel type, and the rear side pincushion type magnetic field is located further rearward than the pincushion type magnetic field generated by the conventional vertical vertical deflection coil shown in FIG. 5 (b). Generates an extended magnetic field 26V.

Therefore, if the deflecting device is configured as described above, the three electron beams emitted from the electron gun can be deflected (pre-deflected) on the electron gun side of the conventional deflecting device. As a result, it is possible to effectively correct the coma error generated between the center beam and the pair of side beams even for large, flat, thin, and wide deflection angle color picture tubes, and improve the convergence quality. You can Further, the pincushion type magnetic field of the vertical deflection coil 21v generated on the electron gun side can improve the focus characteristic and improve the image quality. Moreover, in this deflecting device, the horizontal deflection coil 21H comes closer to the neck side, and the deflection center of the horizontal deflection magnetic field also moves backward. Therefore, especially for a horizontally long color picture tube having an aspect ratio of 16: 9. Can be effective.

[0020]

The rear end of the first deflection coil for deflecting the electron beam emitted from the electron gun of the color picture tube in the major axis direction of the screen and the second deflection coil for deflecting the electron beam in the minor axis direction of the screen. In a deflection device for a color picture tube, which comprises a saddle shape in which a bend portion bent outward is formed on a crossover portion of the portion, and at least a part of these first and second deflection coils are arranged to overlap each other, When the second deflection coil is positioned inside the first deflection coil, the deflection magnetic field generated by the second deflection coil that deflects the electron beam in the short axis direction of the screen is arbitrarily extended in the rear direction where the electron gun is located. Therefore, it is possible to easily form a magnetic field having a different desired distribution by the color picture tube. As a result, good convergence can be obtained and focus characteristics can be obtained even for large-sized, flat type, thin type, and wide deflection angle color picture tubes in which self-convergence that concentrates three electron beams arranged in a row on the entire screen is difficult. Can be improved.

[Brief description of drawings]

FIG. 1 (a) is a diagram showing a configuration of an in-line type color picture tube deflecting device according to an embodiment of the present invention, FIG.
(B) is a diagram showing the arrangement of the horizontal and vertical deflection coils.

FIG. 2 (a) is a diagram showing a distribution of a magnetic field generated by a horizontal deflection coil of the deflection device, and FIG. 2 (b) is a diagram showing a distribution of a magnetic field generated by a vertical deflection coil.

FIG. 3 is a diagram showing a configuration of a color picture tube.

FIG. 4A is a diagram showing a magnetic field of a pincushion type magnetic flux density distribution generated by a horizontal deflection coil of a self-convergence in-line type color picture tube deflecting device;
(B) is a figure which shows the magnetic field of the barrel type magnetic flux density distribution which the vertical deflection coil generate | occur | produces.

5A is a diagram showing a distribution of a magnetic field generated by a horizontal deflection coil of a deflection apparatus for a self-convergence in-line type color picture tube, and FIG. 5B is a view showing a magnetic field generated by the vertical deflection coil. It is a figure which shows distribution.

[Explanation of symbols]

 20 ... Separator 21H ... Horizontal deflection coil 21V ... Vertical deflection coil 22H, 22V ... Bend part 23H, 23V ... Bend part 24 ... Core

Claims (2)

[Claims] 1. A first deflection coil for deflecting an electron beam emitted from an electron gun of a color picture tube in a major axis direction of a screen and a second deflection coil for deflecting the electron beam in a minor axis direction of a screen. In a deflection device for a color picture tube, which comprises a saddle type in which a bend portion is formed by bending an outward bend at a crossover portion of an end, and at least a part of these first and second deflection coils are arranged to overlap each other. A deflection device for a color picture tube, wherein the second deflection coil is located inside the first deflection coil. 2. The deflection device for a color picture tube according to claim 1, wherein the rear portion of the second deflection coil projects rearward of the rear end portion of the first deflection coil.