JPS6280947A - Deflection yoke - Google Patents

Abstract

PURPOSE:To obtain a deflection yoke which can vary the coma aberration by providing an auxiliary coil for vertical deflection coil on the central portion of a magnetic substance shaped like the letter E and connecting a variable resistance parallel to the auxiliary coil so as to flow the vertical deflection current through the auxiliary coil. CONSTITUTION:The magnetic substances 21 shaped like the letter E are arranged in the horizontal direction 16 opposingly to each other, and the auxiliary coil 15 is wound on the central portion of the said magnetic substance 21. The auxiliary coil 15 is connected to the vertical coil 3 in series, and the variable resistance 13 is connected parallel to the auxiliary coil 15 to vary the current in the auxiliary coil 15. If the corrected amount is not optimal, by optimizing the number of turns of the auxiliary coil 15 and the shape of the said magnetic substance 21 of the optimum misconvergence pattern can be obtained. Thereby, the coma aberration caused by the combination of the CPT and the deflection yoke can be controlled variably to obtain pictures of high quality convergence.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a deflection yoke for color televisions or color display cathode ray tubes, and particularly for coma aberration (raster deviation between the center beam and side beams in an in-line electron gun).
The present invention relates to a deflection yoke having means suitable for correcting misconvergence.

[Background of the invention]

As described in Utility Model Application No. 58-132203, the conventional device has a pair of E which are horizontally opposed to each other at the rear of the electron gun side.
When power is distributed to the E-shaped magnetic material, and auxiliary coils for the vertical deflection coil are provided in the center and side portions of the E-shaped magnetic material, when a vertical deflection current is passed through the auxiliary coil, a six-pole magnetic field is formed. This is a method of correcting misconvergence of coma aberration at the top/bottom of the screen, and the one-piece method requires three sets of correction coils, and does not take into account variations due to the combination of the color display cathode ray tube and the deflection yoke.

Hereinafter, the conventional technology described in the above specification will be explained with reference to the drawings.

FIG. 10 is a perspective view showing a general deflection yoke. Same figure? (where 1 is a deflection yoke, 2 is a horizontal deflection coil,
3 is a vertical deflection coil, 4 is a main core, 5 is a separator, 6
is a clip.

FIG. 11 is a sectional view of the vertical deflection coil 3.

In the figure, 7 is a line of magnetic force, 8.8R, 8G, and 8B are electron beams, 9 is a vertical center line, and 10 is a vertical deflection force.

Among the above magnetic fields, the barrel-shaped magnetic field of the vertical deflection coil 3 is such that the windings near the vertical center line 9 of the deflection yoke are sparser than those at both ends, as shown in FIG. Therefore, the green electron beam 8R located in the center (electron beam 8G for G is 1, red ■, blue located at both ends)
, 8B, the deflection amount lO is substantially reduced.

As shown in the raster pattern in Figure 11E12, KG's lath J
12G results in a misconvergence 17 called so-called coma aberration, which is located inside compared to the R and B rasters 12R and 12B.

FIG. 13 is a perspective view of a conventional deflection yoke having a coma aberration adjustment function. It will be appreciated that the auxiliary core 21 is provided on the electron gun side of the vertical deflection coil 3, and the auxiliary coil 15 is wound therein.

FIG. 14 is a front view showing the sub-core 21 and the auxiliary coil 15 wound therein in the 13th rgJ.

As can be seen from these figures, protrusions 22 are formed in the vicinity of the horizontal central axis 16 and in the vicinity where the angle α with respect to the vertical central axis is approximately 30°, so as to guide and strengthen the magnetic flux 7. Further, the sub-core is formed in an E-shape.

kl, the auxiliary coil 15171m Vertical deflection'The 6-pole magnetic field is completed by passing the current, and the coma aberration at the top/bottom of the screen is corrected, but according to the 0-wire method, the correction coil is 3
A set of color display cathode ray tubes (C
Variations due to the combination of the deflection yoke (DY) and the deflection yoke (PT) were not considered.

[Purpose of the invention]

An object of the present invention is to provide a deflection yoke that can easily correct coma aberration on the upper and lower sides of the screen (1-1) and that can vary the coma aberration.

[Summary of the invention]

I-.1 The deflection yoke according to the present invention has the following features:
This is a deflection yoke for color cathode ray tubes having multiple electron guns in an in-line arrangement, in which an E-shaped magnetic material consisting of a pair of horizontally opposing magnetic materials is arranged on the electron gun side (backward) of the horizontal deflection coil. An auxiliary coil for the vertical deflection coil is provided in the center of the E-shaped magnetic body, a variable resistor is connected in parallel with the auxiliary coil, and a six-pole magnetic field is formed by flowing a vertical deflection current through the auxiliary coil. It is characterized by being able to correct and vary coma aberration.

[Embodiments of the invention]

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

The first part is a side view of a deflection yoke provided with six coma aberration correction auxiliary coils 15 of the present invention. Auxiliary coil 1 for main correction
5 is placed behind the horizontal deflection coil on the electron gun side.
A cross-sectional view of the auxiliary coil 15 is shown in FIG.

E-shaped magnetic members 21 are arranged to face each other in the horizontal direction 16, and an auxiliary coil 15 is wound around the center of the E-shaped magnetic members 21. The auxiliary coil 15 is connected in series with the vertical coil 3 as shown in FIG.
A variable resistor 13 is connected in parallel with the auxiliary coil 15 to vary the current flowing through the auxiliary coil 15.

FIGS. 4 to 6 show the magnetic field distribution due to the coil. FIG. 5 shows that in the initial stage of vertical deflection, the side electron beams 8B, 8R receive a deflection force lO in the opposite direction to the deflection direction, for example, when the side electron beams 8B, 8R are deflected upward.
R is apparently positioned above and below the center beam 8G. Then, the electron beam 8B is gradually deflected to a position as shown in FIG.

When 8G and 8R arrive, the center beam 8G receives a larger deflection force 10 than the side beams 8B and 8R due to the pincushion magnetic field. For that purpose, a center beam raster 12G and a side beam raster 12B as shown in Fig. 12 are used.

The amount of deviation from the center of 12R (hereinafter referred to as coma aberration) is corrected, resulting in a misconvergence pattern tonal as shown in FIGS. 7 to 9.

In the case shown in FIG. 7, the amount of correction is insufficient, and by increasing the variable resistor 13 shown in FIG. 3, the misconvergence pattern shown in FIG. 9 is obtained.

In the case shown in Figure 8, the amount of correction is over.

Similarly, by reducing the variable resistor 13 shown in FIG. 3, the misconvergence pattern shown in FIG. 9 is obtained.

If the amount of correction is not optimal as shown in FIGS. 7 and 8, the best misconvergence can be achieved by optimizing the number of turns of the auxiliary coil 15 and the shape of the E-shaped magnetic material 21 (thickness or inner diameter of the magnetic material). You can get patterns.

〔Effect of the invention〕

According to the present invention, it is possible to eliminate the need for a magnetic field control element for coma aberration correction provided inside the CPT, and
Combination of the T and the deflection yoke makes it possible to variably adjust the coma aberration caused by the difference, and to provide a practically effective deflection yoke for obtaining an image with good convergence quality.

[Brief explanation of drawings]

Figure 1 is a perspective view of a deflection yoke with a coma aberration adjustment function according to the present invention, Figure 2 is a front view showing the E-shaped core shown in Figure 1 and the auxiliary coil wound around it, and Figure 3 is an auxiliary coil. The connection diagram of the coil, vertical deflection coil, and variable resistor, Figure 4 is @
Figure 2 is a magnetic field line distribution diagram, and Figures 5 and 6 are diagrams explaining the principle of the invention. 7, 8, and 9 are pattern diagrams after misconvergence correction according to the method of the present invention, FIG. 10 is a perspective view showing a conventional deflection yoke, and FIG. 11 is a vertical deflection coil in FIG. 10. Fig. 12 is a raster pattern diagram representing coma aberration, Fig. 13 is a perspective view of a conventional deflection yoke with a coma aberration adjustment function, and Fig. 14 shows an E-shaped core and an auxiliary coil wound around it. FIG. l...Deflection yoke, 2...Horizontal deflection coil. 3... Vertical deflection coil, 4... Core. 5...Separator, 7...Vertical deflection magnetic field. 8, 8R, 8G, 8B...electron beam. 13...Variable resistance, 15...Auxiliary coil. 21...E-shaped magnetic material. Part 2

Claims (1)

[Claims] 1. In a deflection yoke for a color cathode ray tube having multiple electron guns in an in-line arrangement, a pair of E-shaped magnetic bodies facing each other in the horizontal direction is arranged behind the electron gun side of the horizontal deflection coil, and the E-shaped magnetic bodies are An auxiliary coil for the vertical deflection coil is provided in the center, a variable resistor is connected approximately in parallel with the auxiliary coil, and the six-pole magnetic field formed by flowing a vertical deflection current through the auxiliary coil is variably adjusted by the resistor. A deflection yoke characterized by being adjustable.