KR19980040958A - Screen distortion and convergence automatic correction deflection device - Google Patents

Abstract

The present invention provides a screen distortion and convergence automatic correction deflection device.

The deflection apparatus forms a horizontal deflection coil and a barrel deflection magnetic field that form a pincushion type deflection magnetic field so as to deflect three electron beams focused and accelerated by the inline type electron guns arranged in a horizontal direction across the entire screen. A deflection device of a self-convergence type cathode ray tube having a vertical deflection coil, wherein the screen side is wide open on the upper and lower sides of the deflection device over its length, and a coil is wound around the electron gun side to generate a magnetic field by applying current. It is characterized by automatically correcting the up and down, left and right screen distortion by having a self-shaped permalloy core.

Accordingly, there is an effect that the distortion of the left and right and the top and bottom of the screen can be corrected by the enhanced pincushion magnetic field on the screen side and the barrel magnetic field on the electron gun side with a simple structure.

Description

Screen Distortion Convergence

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deflection device mounted on a collar receiving tube incorporating an inlay electron gun, and more particularly, to a deflection device which automatically corrects convergence and screen distortion by a deflection magnetic field.

In FIG. 1, a panel 12 (see FIG. 2) having a fluorescent screen 20 formed on a rear surface of a face plate 18 and an electron gun 11 for forming electron beams 19a and 19b and emitting them toward the screen 20. Collar cathode including a neck 14 for supporting the neck, a funnel 13 connecting the neck 14 and the panel 12, and a deflection yoke assembly 17 mounted to the neck-funnel connection portion. The tube 10 is shown.

The funnel 13 is formed with an inner conductive layer (not shown) in contact with the anode terminal 15. The shadow mask 16 having a plurality of apertures or slits 16a formed in a predetermined arrangement is detachably mounted to the panel 12 at a predetermined distance from the screen 20.

The deflection yoke assembly 17 has a pair of film-like horizontal deflection members and a vertical deflection member, respectively. The horizontal deflection member forms a horizontal deflection magnetic field so as to horizontally deflect the motion paths of the electron beams 19a and 19b when a horizontal deflection current is applied, while the vertical deflection member is applied when the vertical deflection current is applied. A vertical deflection magnetic field is formed to vertically deflect the motion of the electron beams 19a and 19b.

By changing the deflection magnetic field in a suitable manner, it is preferable that electron beams 19a and 19b be scanned over the entire surface of the screen 22 to form a two-dimensional image in the cathode ray tube panel 12 with an optimum deflection sensitivity. In addition, the deflection caused by the magnetic field forms a pincushion magnetic field by the horizontal deflection member and a barrel magnetic field by the vertical deflection member, thereby easily converging three kinds of electron beams of the inline electron gun.

Since the magnetic field distribution causes screen pincushion type left and right screen distortions, a parabolic phase current synchronized with a vertical magnetic field is supplied to the horizontal deflection coil by an external circuit to compensate for the left and right screen distortions. Distortion phenomenon appears.

According to Japanese Patent Application Publication No. 4-1986 for solving this problem, as shown in Fig. 3, the horizontal deflection coils 3 arranged above and below the arrangement direction HH of the inline-type electron gun are located on the upper and lower sides of the reference line on the same side. Magnets 2a and 2b of different lengths are respectively installed to perform magnetic field adjustment. Left and right failure type distortion is corrected by a pincushion magnetic field formed by the long magnet 2a. At this time, the upper and lower horizontal lines of the screen are also corrected by the pincushion magnetic field, and the upper and lower failure type distortions are corrected, but the upper and lower distortions are corrected by the magnet 2b having a short length due to the flattening and optical deflection angle of the screen.

However, the above-described magnets have a problem in that their lengths or poles must be changed in order to effectively and properly adjust the screen distortion.

Although the vertical failure type distortion is effectively corrected by the above-described horizontal pincushion magnetic field, the left and right failure type distortion becomes a barrel shape from the convergence characteristic of the vertical deflection magnetic field, thereby forming a raster that makes the distortion even more severe. In order to correct the left and right distortion with convergence, only the screen side magnetic field of the vertical deflection magnetic field needs to be pincushioned.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and an object thereof is to provide a screen distortion and convergence automatic correction deflection device capable of automatically correcting convergence and left and right screen distortion even in a flattened and wide deflection angled cathode ray tube.

1 is a partial cross-sectional plan view schematically showing the configuration of a color cathode ray tube;

2 is a partial cross-sectional view of the screen of FIG. 1;

3 is a front view of a deflection device for adjusting screen distortion by a magnet;

4 is a top plan view of a deflector according to the present invention;

5 is a front view seen from the front of the deflector.

* Description of the symbols for the main parts of the drawings *

10: cathode ray tube 11: electron gun

12: Panel 13: Funnel

14: neck 15: positive terminal

16: shadow mask 18: faceplate

19a, 19b: electron beam 20: screen

P: U-shaped permalloy core

In order to achieve this object, the screen distortion and convergence automatic correction deflection apparatus according to the present invention is a pincushion type deflection magnetic field that deflects three electron beams connected and accelerated by an inline type electron gun in a horizontal line across the entire screen. A self-converging cathode ray tube deflection apparatus having a horizontal deflection coil forming a vertical deflection coil and a vertical deflection coil forming a barrel-type deflection magnetic field, wherein the screen side is wide open on the upper and lower sides of the deflection apparatus, and a current is supplied to the electron gun side. It is characterized in that the coil for generating a magnetic field by applying a U-shaped permloy core is respectively provided to automatically correct the upper and lower, left and right screen distortion.

The coil may be connected in series with a vertical deflection coil to apply a vertical deflection current, and the core may be a magnetic metal or an alloy other than Permalloy.

Hereinafter, with reference to the accompanying drawings will be described in detail the configuration and operation of the embodiments of the present invention.

4 shows a top plan view of the deflector according to the invention, and FIG. 5 shows a front view of the deflector in front.

4 and 5, U-shaped permalloy cores P are installed on the upper and lower sides of the deflector over the length in the axial direction thereof. The U-shaped permalloy core (P) is composed of an open portion (40, 40 ') with a wide open screen side as shown, and a connecting portion (30) narrowly connected to the electron gun side, the current is applied to the connecting portion (30) The coil for generating the magnetic field is wound.

The pincushion type magnetic field is strongly formed according to the opening degree formed by the openings 40 and 40 '. Therefore, the left and right distortions of the screen are corrected by the pincushion magnetic field formed by the openings 40 and 40 '.

In addition, the coil is connected in series with the vertical deflection coil, the upper and lower screen distortion occurs according to the correction of the left and right distortion of the screen. To correct this vertical distortion, the barrel-shaped magnetic field must be strengthened at the electron gun side. Therefore, by applying the vertical deflection current in series via a suitable step down means, it is possible to correct the vertical distortion along with the left and right screen distortions.

Therefore, as described above, the horizontal deflection field of the deflection device is pincushioned and the vertical deflection field is barreled to achieve self-convergence, and further, the structure of the screen is enhanced by the enhanced pincushion field on the screen side and the barrel field on the electron gun side with a simple structure. And up and down distortion can be corrected.

Claims (2)

Horizontal deflection coils forming a pincushion-type deflection magnetic field and vertical deflection coils to deflect three electron beams focused and accelerated by an inline-type electron gun arranged in a horizontal direction across the screen. In the deflection device of the self-convergence cathode ray tube, On the upper and lower sides of the deflection apparatus, the screen side is wide open over its length, and the current is applied to the electron gun side, and U-shaped permalloy cores with coils for generating magnetic fields are respectively provided to automatically correct top, bottom, left and right screen distortions. Screen distortion and convergence automatic correction device, characterized in that. The apparatus of claim 1, wherein the coil is connected in series with a vertical deflection coil.