JP2000138034A - Color television display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a color television display device capable of correcting a mis-convergence particularly at the central part of the image plane of a picture tube according to the state of displacement of the convergence. SOLUTION: A deflection yoke 15 is mounted on the outside periphery of a neck part of a picture tube 11, and at least one permanent magnet 20 magnetized in an NS form is mounted at an intermediate part in the tube axis direction on the deflection yoke 15. A mis-convergence, in particular, a mis-convergence at the central part of the image plane can be corrected by finely varying the magnetic field distribution generated by the deflection type 15 by the use of the permanent magnet 20. The most suitable convergence correction can be carried out by selecting the number, the mounting position, the mounting direction, the magnetic force and/or the size of the permanent magnet(s) 20 according to the state of the mis-convergence.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color television display device having a deflection yoke, and more particularly to a device capable of correcting misconvergence occurring on a picture tube screen.

[0002]

2. Description of the Related Art Conventionally, as a picture tube (cathode ray tube) used for a display device such as a color television receiver and a color display device, a tube provided with an in-line arranged electron gun is widely used. (Red), G (green), B
The (blue) electron guns are arranged on the X axis. A deflection yoke device is mounted on the neck of the picture tube to deflect and scan an electron beam from an electron gun.

As is well known, a deflection yoke device is configured by mounting a ferrite core, a horizontal deflection coil, and a vertical deflection coil on a bobbin. By driving the deflection yoke device, a raster image is displayed on a picture tube screen. Is formed.

The above deflection yoke device generally reduces the misconvergence by making the horizontal deflection magnetic field a pincushion type distribution and the vertical deflection magnetic field distribution a barrel type distribution. Convergence cannot be eliminated, and misconvergence often occurs around the screen as shown in FIG.

In FIG. 5, the solid line is R (red) and the dotted line is B
(Blue) shows the state of deviation of the convergence, and the deviation at the corner portion (peripheral portion) on the screen is remarkable. The state of the convergence shift is reversed between the upper part and the lower part of the screen.

As one means for correcting such misconvergence, there is a conventional method using a ferrite sheet as shown in FIG. In FIG. 6, reference numeral 21 denotes a deflection yoke device, in which a horizontal deflection coil (not shown) is mounted inside a bobbin 22, and a vertical deflection coil 23 is mounted outside. The ferrite sheet 24 is provided with an NS-magnetized magnet 25 at one end. The ferrite sheet 24 is inserted into a gap between the deflection yoke device 21 and the picture tube, and misconvergence is observed while observing the state of deviation of convergence. Attach it to the minimum position.

Generally, since misconvergence tends to occur at the corners of the picture tube screen, the ferrite sheet 24 is placed at a position corresponding to each corner, that is, at a position shown by dotted lines A to D in FIG. I am trying to install it.

As another means for correcting misconvergence, there is a method of appropriately adjusting the winding distribution of the deflection coil. For example, the horizontal deflection coil has a bosh shape that expands from the neck portion of the picture tube to the funnel portion, and is divided into several sections. The number of turns in each section, coil density, etc. Is adjusted, misconvergence can be corrected.

[0009]

In the conventional deflection yoke device, misconvergence in the peripheral portion of the screen can be corrected by using the ferrite sheet 24, but it is newly added in the vicinity of the central portion of the screen. Misconvergence may occur.

FIG. 7 shows this misconvergence state. In FIG. 7, the misconvergence at the periphery of the screen is corrected by the ferrite sheet 24, but the misconvergence opposite to that in FIG. 5 occurs at the center of the screen. Such misconvergence tends to be more noticeable as the tube surface of the picture tube becomes flatter.

Although the misconvergence can be corrected by adjusting the winding distribution of the deflecting coil, the winding operation is extremely troublesome, and the deviation of the convergence differs in each of the receivers. Adjustment of the distribution is a precise operation, and there is a disadvantage that the state of convergence changes even if the distribution changes slightly.
Further, when the winding distribution is changed, the deflection amplitude may also be changed, and a new problem that the display raster is distorted occurs.

In view of the above problems, it is an object of the present invention to provide a color television display device which can correct misconvergence with a simple configuration and whose amplitude does not change with the correction. It is.

[0013]

According to a first aspect of the present invention, there is provided a color television display device comprising: a picture tube having an electron gun for generating an in-line type electron beam in a neck portion;
A deflection yoke attached to an outer periphery of the neck portion and deflecting the electron beam in a horizontal and vertical direction to form a raster in a picture tube; the deflection yoke generates a magnetic core and horizontal and vertical deflection magnetic fields; And having a horizontal and vertical deflection coil to the, in the tube axial direction intermediate portion of the deflection yoke at a position facing the outer peripheral portion of the picture tube,
Attaching at least one NS-magnetized permanent magnet piece;
A color television display device characterized in that misconvergence generated in the center of the picture tube of the picture tube by the magnet is corrected.

According to the first aspect of the present invention, the distribution of the magnetic field generated in the deflection yoke is minutely changed by the permanent magnet to improve convergence.

The permanent magnets are mounted on the inner peripheral surface of the horizontal deflection coil of the deflection yoke, and the number and mounting position of the permanent magnets are determined according to the state of the misconvergence.
The mounting direction is set.

The permanent magnet sets the magnetic force or magnitude according to the state of the misconvergence, and further sets the magnetic force or magnitude according to the deflection frequency of the deflection yoke.

[0017]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view showing an embodiment of the color television display device of the present invention.

In FIG. 1, reference numeral 11 denotes a picture tube, and a neck portion 13 provided with an electron gun 12 arranged in line.
And a widening portion 14 (screen) on the front surface.

Reference numeral 15 denotes a deflection yoke device, and the picture tube 1
It is attached to the outer periphery of the portion that transitions from the first neck portion 13 to the widening portion 14. The deflection yoke device 15 has a saddle-type horizontal deflection coil 16 for deflecting the electron beam in the horizontal direction, a saddle-type vertical deflection coil 17 for deflecting the electron beam in the vertical direction, and is mounted so as to surround the deflection coils 16, 17. And an annular ferromagnetic core 18. A bobbin 19 is arranged between the deflection coils 16 and 17. The deflection coils 16 and 17 are not limited to the saddle type, but may be a toroidal type.

As shown in FIG. 2, the horizontal deflection coil 16 has a front end 162 which is formed to extend conically from a rear end 161 corresponding to the periphery of the neck portion 13 toward the widening portion 14. are doing. The horizontal deflection coil 16 is so-called section-wound, and has a plurality of winding portions 163.

Further, in the present invention, the horizontal deflection coil 1
An NS-magnetized permanent magnet 20 is attached to an inner peripheral portion of a substantially central portion in the tube axis direction (the direction of arrow XX in FIG. 1). This magnet 20 is for correcting misconvergence at the center of the screen shown in FIG. 7, and one or a plurality of magnets 20 are attached according to the state of deviation of convergence.

In the embodiment of the present invention, the magnet 20 is NS-magnetized as shown in FIG. 3 and is a small piece having a width of about 2 mm to 10 mm. The magnetic force, size, mounting position, and mounting direction are as follows. It is set arbitrarily according to the deviation of convergence, and the distribution of the magnetic field generated in the deflection yoke can be minutely changed by the magnet 20 to improve the convergence.

In FIG. 2, the magnet 20 is connected to the horizontal deflection coil 1.
Attach two to the upper left and lower right of the figure 6, 16
An example is shown in which it is attached to an intermediate portion between the front end 1 and the front end 162. FIG. 4 shows an example of misconvergence correction in this case. As can be seen from FIG. 4, the misconvergence at the center of the screen, which has conventionally occurred (FIG. 7), has been almost completely eliminated.

The magnets 20 are mounted to correct the misconvergence according to the state of the misconvergence. Therefore, only one magnet or four magnets may be used. By moving the mounting position in the up, down, left, and right directions from the mounting position in FIG. 2, an optimum position can be selected, and the position may be set by checking the actual degree of convergence correction. Further, the direction in which the magnet 20 is mounted is arbitrarily selected in accordance with the upper portion, the lower portion, and the like of the screen.

Further, the results of the experiment confirmed that changing the magnet 20 in accordance with the deflection frequency is more effective. In other words, when the horizontal deflection frequency is 31.5 KHz, which is higher than 15.75 KHz, the effect of correcting the misconvergence is higher when the size of the magnet 20 is increased. Alternatively, the magnetic force may be increased as the frequency increases.

In the embodiment of the present invention, the magnet 20
Even when was attached, no change in the amplitude of the screen was observed, and it was also confirmed that the scanning state was good.

If the mounting position of the magnet 20 is too close to the front end 162 of the horizontal deflection coil 16, the screen raster will be distorted into a pincushion shape or the like.
An intermediate portion of the horizontal deflection coil 16 in the tube axis direction is desirable.

As described above, according to the color television display device of the present invention, misconvergence on the picture tube screen, particularly misconvergence occurring at the center of the screen, can be favorably corrected. The mounting of the magnet 20 is as follows.
It can be mounted at any position according to the deviation of convergence in the actual receiver, and the mounting method can be performed using adhesive or tape.Since the configuration is simple and the mounting work is simple, it is practical Rich in nature.

[0030]

As described above, according to the present invention, the use of the magnet 20 makes it possible to easily correct misconvergence on the picture tube screen, in particular, misconvergence occurring at the center of the picture. Also, the magnet 20 may be attached by using an adhesive or a tape.
Since the installation work is simple, it is practical.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a color television display device according to an embodiment of the present invention.

FIG. 2 shows a deflection yoke device viewed from the direction of arrow a in FIG.
FIG. 2 is a front view mainly showing a horizontal deflection coil.

FIG. 3 is a front view showing a misconvergence correction magnet.

FIG. 4 is an explanatory diagram illustrating the operation of misconvergence correction according to the present invention.

FIG. 5 is an explanatory diagram showing a first example of conventional misconvergence.

FIG. 6 is a perspective view showing a deflection yoke device provided with a conventional misconvergence correction device.

FIG. 7 is an explanatory diagram showing a second example of conventional misconvergence.

[Explanation of symbols]

 11 picture tube 15 deflection yoke device 16 horizontal deflection coil 17 vertical deflection coil 20 permanent magnet

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[Procedure amendment]

[Submission date] November 9, 1998 (1998.11.
9)

[Procedure amendment 1]

[Document name to be amended] Drawing

[Correction target item name] All figures

[Correction method] Change

[Correction contents]

FIG.

FIG. 2

FIG. 3

FIG. 4

FIG. 5

FIG. 7

FIG. 6

Claims (5)

[Claims] 1. A picture tube having an electron gun for generating an in-line type electron beam in a neck portion, and a raster attached to an outer periphery of the neck portion to deflect the electron beam horizontally and vertically to form a raster in the picture tube. A deflection yoke, wherein the deflection yoke has a magnetic core, horizontal and vertical deflection coils for generating a horizontal deflection magnetic field and a vertical deflection magnetic field, and is a tube axial direction intermediate portion of the deflection yoke, At least one N
A color television display device comprising: an S-magnetized permanent magnet; and a magnet that corrects misconvergence generated in a central portion of a picture tube of the picture tube. 2. The color television display device according to claim 1, wherein said permanent magnet is attached to an inner peripheral surface of said horizontal deflection coil of said deflection yoke. 3. The color television display device according to claim 1, wherein the number, the mounting position, and the mounting direction of the permanent magnets are set according to the state of the misconvergence. 4. The color television display device according to claim 1, wherein the permanent magnet sets a magnetic force or a magnitude according to the state of the misconvergence. 5. The color television display device according to claim 1, wherein said permanent magnet sets a magnetic force or a magnitude according to a deflection frequency of said deflection yoke.