JP2000113837A - Deflection yoke - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a deflection yoke for an in-line type color picture tube capable of correcting the distortion of horizontal deflection magnetic field distribution with a simple means and capable of obtaining a good convergence characteristic. SOLUTION: This deflection yoke is fitted to an in-line type color cathode-ray tube provided with a pair of saddle type horizontal deflection coils 1 and a pair of vertical deflection coils. Horizontal auxiliary coils 3 are arranged on the neck side B than the middle section in the CRT tube axis direction of the window sections 2 of the horizontal deflection coils 1 respectively, and a pair of auxiliary magnets 4 (5) are arranged above and below respectively on the opening section side A than the middle section.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deflection yoke for an in-line type color picture tube, and more particularly to a deflection yoke for a horizontal deflection magnetic field distribution which can be corrected by simple means to obtain a good convergence characteristic. The present invention relates to a deflection yoke for a pipe.

[0002]

2. Description of the Related Art In general, in a deflection yoke for a color picture tube having an in-line array of electron guns, the deflection yoke has a non-uniform magnetic field distribution so that the deflection yoke can be connected to the color picture tube without using a correction means such as an external circuit. It has a self-convergence function in which the three electron beams are made to substantially coincide over the entire screen only by the combination of the yokes.

That is, by forming a horizontal deflection magnetic field into a pincushion magnetic field and a vertical deflection magnetic field into a barrel magnetic field,
The convergence between the two side beams can be corrected on the deflection yoke side (for example, only by adjusting the winding distribution).

Recently, the definition of the screen has become remarkably high, and it has become necessary to remove misconvergence caused by slight distortion of the horizontal deflection magnetic field distribution, which has not conventionally been a problem. However, since there is a limit in the winding accuracy of the horizontal deflection coil and the like, it is very difficult to remove a slight distortion of the horizontal deflection magnetic field distribution required only by adjustment by the winding distribution.

In order to solve the above-mentioned problem, for example, Japanese Patent Laid-Open Publication No. HEI 8-18988 discloses a window portion of a horizontal deflection coil 1 corresponding to a color picture tube neck side B as shown in FIG. 2, a horizontal auxiliary coil 3 for generating a magnetic field for enhancing the magnetic field on the center side of the horizontal deflection magnetic field is arranged, and the horizontal correction coil 3 generates a green G electron beam at both ends of the color picture tube screen. A deflection yoke configured to improve convergence characteristics in accordance with the electron beams of blue B and red R is disclosed. Similarly, as shown in FIG. 8, a deflection yoke for improving the convergence characteristic by disposing a plurality of the horizontal auxiliary coils 3 between the opening side A and the neck side B of the horizontal deflection coil 1 has also been disclosed.

Further, Japanese Utility Model Publication No. 7-22032 discloses that
As shown in FIG. 9, in the deflection yoke in which the slit 9 is provided in the mold bobbin 8 and the horizontal deflection coil 1 is wound in a saddle shape, a part of the inner surface of the mold bobbin 8 in the window 2 of the horizontal deflection coil 1 is formed. A one-turn auxiliary slit 9A is provided,
A deflection yoke configured to remove a slight distortion of the horizontal deflection magnetic field distribution by winding the horizontal auxiliary coil 3 along this is disclosed. In this deflection yoke, the horizontal correction magnetic field can be generated in the same direction as the horizontal deflection magnetic field or in the opposite direction. By locally generating the magnetic field, as shown in FIGS. 11 (a) and 11 (b). Na S-in
In addition to misconvergence called g and G-drop, other image distortion and the like were corrected.

Further, Japanese Patent Publication No. 58-9541 discloses that
As shown in FIG.
And a horizontal auxiliary coil passing along the tube axis direction from the rear end side C to the front end side D corresponding to the window 2 of the horizontal deflection coil 1 in the deflection yoke in which the horizontal deflection coil 1 is wound in a saddle shape. 3, a deflection yoke having a configuration for correcting the distortion of the distribution of the horizontal deflection magnetic field generated from the horizontal deflection coil 1 is disclosed.

[0008]

In the deflection yoke shown in FIGS. 7 and 8, when the horizontal auxiliary coil is arranged on the neck side or the opening side, the magnetic field on the center side of the horizontal deflection coil is strengthened. As a result, the horizontal deflection magnetic field becomes a barrel magnetic field and the S-ing misconvergence increases, so that it is necessary to correct this misconvergence by using a vertical deflection magnetic field and other circuits. In addition, in the case of the deflection yoke shown in FIG. 10, by disposing the horizontal auxiliary coil, similarly to the deflection yoke shown in FIGS. There is a drawback in that local distortion of the deflection magnetic field distribution cannot be corrected. On the other hand, in the deflection yoke shown in FIG. 9, when the horizontal auxiliary coil is wound in the same direction as the horizontal deflection coil, the S-ing misconvergence increases as in the deflection yoke shown in FIGS. There was a difficulty to do it. Further, when the coil is wound in the direction opposite to the horizontal deflection coil and the horizontal auxiliary coil is arranged on the neck side, a pattern opposite to the S-ing misconvergence occurs in the middle portion of the screen. There was a drawback that caused deterioration.
Further, when the horizontal auxiliary coil is arranged on the opening side, there is a problem that the G-drop misconvergence and the lateral deviation of the red R and blue B electron beams in the peripheral portion of the screen are increased.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a deflection yoke for an in-line type color picture tube in which distortion of the horizontal deflection magnetic field distribution can be corrected by simple means and good convergence characteristics can be obtained.

[0010]

A deflection yoke mounted on an in-line type color cathode ray tube comprising a pair of saddle type horizontal deflection coils and a pair of vertical deflection coils, wherein each of the horizontal deflection coils 1 and 1 is provided with a deflection yoke. The horizontal auxiliary coils 3 and 3 are arranged on the neck side B of the window parts 2 and 2 at the middle part in the cathode ray tube axial direction, and are positioned above and below the opening part A from the middle part, respectively. Magnets 4, 4
The deflection yoke is formed by disposing (5, 5).

In the deflection yoke configured as described above, the horizontal correction magnetic field generated from the horizontal auxiliary coil on the neck side of the horizontal deflection coil is converted into a barrel magnetic field by a horizontal correction magnetic field, as shown in FIG. Misconvergence is corrected. However, at the same time, as shown in FIG. 5, the S-ing misconvergence increases at the upper and lower ends of the screen, and a lateral shift of the red R and blue B electron beams occurs at the corner of the screen. Therefore, in the present invention, the S-ing misconvergence at the upper and lower ends of the screen and the lateral shift of the red R and blue B electron beams at the corners of the screen are arranged vertically above and below the opening in the middle of the tube axis. Is corrected by the correction magnet.

That is, for example, in the case of an electron beam deflected to the upper right of the screen, the electron beam reaching the upper right intermediate point passes near the magnet 4 attached to the upper right, and the pin magnetic field generated from the magnet 4 , The electron beams R, G, and B receive a force. However, considering the horizontal and vertical components of the force applied to the electron beams R, G, and B, the horizontal component is in the same direction. The vertical component is B
It acts more strongly on the upper side for the beam and lower on the R beam. As a result, Si as shown in FIG.
ng misconvergence is corrected. On the other hand, the electron beam that reaches the upper right corner of the screen passes through a place relatively far from the magnet 4, so that the effect of the pin magnetic field generated from the magnet 4 is reduced. However, between the R beam and the B beam, the B beam that interlinks more with the magnetic field of the magnet 4 receives a greater force than the R beam, and the B beam moves to the left from the R beam.
As a result, the lateral deviation between the red R and blue B electron beams at the corners of the screen as shown in FIG. 5 is corrected. An optimum horizontal correction magnetic field can be generated by appropriately setting the size and the number of turns of the horizontal auxiliary coil, the strength of the magnet, and the arrangement position.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described with reference to FIGS.
This will be described more specifically. FIG. 1 is a schematic diagram illustrating a deflection yoke according to the present invention, FIG. 2 is a schematic diagram illustrating a simple configuration of a horizontal deflection coil, and FIG. 3 is a sectional view of a main part of the deflection yoke.

In the figure, reference numerals 6 and 6 denote coil separators formed of a flame-retardant resin or the like, and a pair of horizontal deflection coils 1 and 1 are housed on the inner peripheral surface thereof and a pair of horizontal deflection coils 1 and 1 are accommodated on the outer peripheral surface thereof. Vertical deflection coils 7, 7 and magnetic core (not shown)
Is installed. Reference numerals 3 and 3 denote horizontal auxiliary coils, which are arranged on the neck side B with respect to the intermediate portions of the window portions 2 and 2 of the horizontal deflection coils 1 and 1 in the axial direction of the cathode ray tube. The size and the number of turns of the horizontal auxiliary coils 3 and 3 can be appropriately set so as to generate an optimum correction magnetic field.

A pair of magnets 4, 4 (5, 5) each having a length of about 10 mm are disposed above and below the opening side A of the coil separators 6, 6, respectively. The pair of magnets 4, 4 (5, 5) are viewed from the screen side, and the upper magnets 4, 4 are S poles on the left side and N poles on the right side, and lower magnets 5, 5 are the left poles on the left side. N pole and S on the right
It is fixed to the coil separators 6, 6 by an adhesive or an adhesive tape or the like so as to be a pole. The magnets 4, 4
(5, 5) Each strength and installation position are set appropriately,
An optimal correction magnetic field can be generated.

In the deflection yoke having such a configuration, a horizontal correction magnetic field for converting the horizontal deflection magnetic field into a barrel magnetic field is generated from the horizontal auxiliary coils 3, 3 on the neck side B of the windows 2, 2 of the horizontal deflection coils 1, 1. As a result, misconvergence in the middle portion of the screen is corrected. However, due to the horizontal correction magnetic fields generated by the horizontal auxiliary coils 3 and 3, S-ing misconvergence increases at the upper and lower ends of the screen as shown in FIG. 5, and red R and blue B electron beams at the corners of the screen. In the present invention, a pair of correction magnets are further disposed above and below the opening side A of the window portions 2 and 2 of the horizontal deflection coils 1 and 1 in the axial direction of the cathode ray tube since lateral displacement occurs. According to 4,4 (5,5), this S
Since the misconvergence of -ing and the lateral deviation of the red R and blue B electron beams are corrected, the green G electron beam and the red R and blue B electron beams substantially coincide with each other, and a highly accurate image without distortion. Can be obtained.

[0017]

According to the present invention, a pair of horizontal auxiliary coils located on the neck side of the horizontal deflection coil window and a pair of correction magnets located above and below the opening side of the horizontal deflection coil window are combined. With this simple means, it has become possible to correct a local misconvergence deviation that could not be corrected by the conventional horizontal auxiliary coil alone. In particular, the reversal phenomenon of misconvergence between the middle portion and the peripheral portion of the screen is improved, and the image quality can be improved relatively inexpensively as compared with a case where another correction circuit or the like is used as in the related art. The practical effect is significant.

[Brief description of the drawings]

FIG. 1 is a simple explanatory view showing a configuration of a deflection yoke according to the present invention.

FIG. 2 is an explanatory diagram showing a simple configuration of a horizontal deflection coil used in the present invention.

FIG. 3 is a sectional view of a main part showing a configuration of a deflection yoke of the present invention.

FIG. 4 is an explanatory diagram of misconvergence in an intermediate portion of a screen.

FIG. 5 is an explanatory diagram of S-ing misconvergence at the lower end of the screen.

FIG. 6 is an explanatory diagram of a lateral shift between red R and blue B electron beams at a screen corner.

FIG. 7 is an explanatory view showing an example of a conventional horizontal deflection coil.

FIG. 8 is an explanatory view showing an example of another horizontal deflection coil of the conventional example.

FIG. 9 is an explanatory view showing an example of another conventional horizontal deflection coil.

FIG. 10 is an explanatory diagram showing an example of another conventional horizontal deflection coil.

FIG. 11 is an explanatory diagram of misconvergence, and FIG.
(A) is an explanatory diagram showing S-ing misconvergence, and (b) is an explanatory diagram showing G-drop misconvergence.

[Explanation of symbols]

 1,1 Horizontal deflection coil 2,2 Window 3,3 Horizontal auxiliary coil 4,4,5,5 Correction magnet 6 Coil separator 7,7 Vertical deflection coil 8 Mold bobbin 9 Slit

Claims (1)

[Claims] 1. A deflection yoke mounted on an in-line type color cathode ray tube comprising a pair of saddle type horizontal deflection coils and a pair of vertical deflection coils, wherein each of the horizontal deflection coils 1 and 1 has a window 2. , 2 are located on the neck side B from the middle part in the axial direction of the cathode ray tube, and the horizontal auxiliary coils 3, 3 are arranged at positions above and below the opening side A from the middle part. A deflection yoke, wherein 4 (5, 5) are arranged.