JPH041986B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION TECHNICAL FIELD OF THE INVENTION The present invention relates to a deflection device for a color picture tube having an in-line array electron gun in which three electron beams are arranged in a row in the horizontal direction.

Technical Background and Problems of the Invention In a color picture tube deflection device having an in-line electron gun in which three electron beams are arranged horizontally in a row, the horizontal deflection coil is saddle-shaped;
By making the vertical deflection coils toroidal type and adjusting the winding distribution of those coils so that the horizontal deflection magnetic field from the horizontal deflection coil has a pink tension type, and the vertical deflection magnetic field from the vertical deflection coil has a barrel type. Self-convergence can be achieved. In such a self-convergence type deflection device, the horizontal deflection magnetic field is of the pink tension type, so when the in-line arrangement direction of the electron gun is the reference line and this reference line is in the horizontal direction, the pincushion distortion in the upper and lower parts is particularly effective. It is corrected to
However, with respect to left and right pincushion distortion, the vertical deflection magnetic field has a barrel shape due to its convergence characteristic, which in turn promotes the distortion, and a raster with left and right pincushion distortion is projected as shown in FIG. In order to correct such raster distortion using a deflection device, it is necessary to form the screen-side magnetic field of the vertical deflection magnetic field into a pink tension type. The device has been put into practical use. However, in color picture tubes with flattened screens or wider deflection angles, vertical pincushion distortion and left/right crisscross distortion become larger, and the horizontal and vertical deflection magnetic field shapes on the screen side become stronger pink tension types. However, it was difficult to do so using conventional methods.

OBJECTS OF THE INVENTION The present invention has been made in view of the above points, and an object of the present invention is to obtain a deflection device that easily corrects the raster distortion described above.

Summary of the Invention The present invention uses the arrangement direction of in-line electron guns as a reference line, and arranges magnetic field generators each consisting of two types of magnets with different lengths between magnetic poles on the screen side on both sides of this reference line in a deflection device. This deflection device effectively corrects the left-right pincushion distortion of the self-convergence system when the reference line is in the horizontal direction, and obtains a distortion-free raster.

Examples of the invention The present invention will be explained in detail below.

FIGS. 2a and 2b are front and side views showing an embodiment of the deflection device of the present invention, and the reference line H-H in the arrangement direction of the in-line array electron gun corresponds to the horizontal direction on the paper in FIG. 2a. . In FIG. 2, a first magnet 2a and a second magnet with different magnetic pole lengths are placed on the same side as the horizontal deflection coil 3 disposed above and below the reference line H-H of the deflection device 1, that is, on both sides of the reference line. A magnetic field adjustment device consisting of a magnet 2b is attached to each. This magnetic field adjusting device provides the following effects.

That is, first, the first magnet 2 having a long length between magnetic poles
The pink tension type magnetic field formed by a acts to correct left and right pincushion distortion. This correction amount can be appropriately selected depending on the effective length of the first magnet 2a, the mounting position, and the magnetic field strength. This first
The horizontal pincushion distortion is corrected by the first magnet 2a in the direction shown by the solid line in FIG. Changes to However, in a color picture tube with a flattened screen or a wide deflection angle, the amount of correction is insufficient, resulting in a raster with residual pincushion distortion.

Therefore, since the effective length of the second magnet 2b, which has a shorter magnetic pole length than the first magnet 2a, works to pull the vertical axis of the vertical axis raster vertically, mainly correcting the vertical pincushion distortion. conduct.
Therefore, by using a magnetic field generating device consisting of two types of magnets having different equal lengths between magnetic poles, a raster whose distortion is corrected as shown in FIG. 4 can be obtained.

In this case, if the vertical distortion after correcting left-right pincushion distortion is barrel-shaped, it is preferable to arrange two types of magnets with different magnetic pole lengths so that their magnetic pole directions are opposite to each other.

FIG. 5 shows another embodiment of the present invention, in which a first magnet 2a and a second magnet 2b whose length between magnetic poles is shorter than that of the first magnet 2a are integrally molded into a convex shape. It is. When the magnetic poles are in the same direction, a simpler magnetic field adjustment device can be obtained. 6 to 8 show still other embodiments of the present invention, in which FIG. 6 shows a magnetic field generating device consisting of the first and second magnets 2a and 2b, which is connected to the horizontal deflection coil of the deflection device 1. It is placed on the rear surface of the flare part of No. 3. FIG. 7 shows a magnetic field generator placed at the outer end of the flared portion of the horizontal deflection coil 3, and FIG. 8 shows a magnetic field generator consisting of two types of magnets with different lengths between magnetic poles, in contrast to FIG. 2a. That is, the shorter length between the magnetic poles is placed on the tube axis side. It goes without saying that the same effects as shown in FIG. 2 can be achieved in any of the cases shown in FIGS. 6 to 8.

Effects of the Invention As described above, according to the present invention, when the reference line in the arrangement direction of the in-line electron gun is in the horizontal direction, the left and right pincushion distortion is corrected by the first magnet, and the residual vertical distortion is corrected by the magnetic pole. The effective length, mounting position, and magnetic field strength of a magnetic field generator consisting of two types of magnets that can be corrected by a second magnet whose length is shorter than the first magnet and whose lengths between magnetic poles are different are appropriately selected. As a result, it is possible to easily correspond to deflection devices having different correction amounts and correction directions for horizontal and vertical distortions, and to obtain a raster without distortion.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing a typical raster shape of the self-convergence system, FIGS. 3 and 4 are schematic diagrams for explaining the raster shape by the deflection device of FIG. 2, FIG. 5 is a schematic front view of main parts showing another embodiment of the present invention, and FIGS. 6 to 8 The figures are a schematic side view and a front view of main parts showing still another embodiment of the present invention. 1... Deflection device, 2a... First magnet,
2b...Second magnet, 3...Horizontal deflection coil.

Claims (1)

[Claims] 1. A horizontal deflection magnetic field by a horizontal deflection coil is applied to a color image receiving space having an in-line array electron gun in which three electron beams are arranged in a row in the horizontal direction, and a vertical deflection magnetic field is applied by a vertical deflection coil. In a self-convergence type deflection device in which the deflection magnetic field is barrel-shaped, at the screen side end of the color picture tube in the deflection device, with the inline arrangement direction as a reference line, on both sides of this reference line, there are mainly raster left and right pincushions. A first magnet that generates a pink tension magnetic field that corrects distortion, and a magnetic pole length that generates a pink tension magnetic field near the vertical axis that corrects vertical distortion of the raster that remains after correcting the left and right pincushion distortion. A deflection device comprising a magnetic field adjusting device each comprising a second magnet having a length shorter than the length between the magnetic poles of the magnet. 2. The deflection device according to claim 1, wherein the first and second magnets are integrally formed so that the magnetic field adjusting device has a convex shape. 3. The deflection device according to claim 1, wherein the magnetic poles of the first and second magnets are arranged on the same side. 4. The deflection device according to claim 1, wherein the magnetic poles of the first and second magnets are arranged oppositely.