JPS63298946A - Deflecting device - Google Patents

Abstract

PURPOSE:To prevent the misconvergence of electron beams from an electron gun of an in-line disposition with no field controller by furnishing a pair of auxiliary magnetic field generating devices which consist of two coils respectively. CONSTITUTION:Auxiliary magnetic field generating devices 15 and 16 which consist of a coil 20 made by winding two coils 20a and 20b respectively are arranged in the vertical direction in the disposition line of electron guns R, G, and B. The coil 20 is connected to a vertical deflecting coil 12 through resistances 22 and 25, and diodes 23 and 24. The current flowing through the coil 20 is varied by the resistance 25, and the current through the coil 20b is regulated minutely by the resistance 22. By the auxiliary magnetic field generated responding to the value of the current through the coil 20, the sensitivity of the electron beams from the electron gun G at the center is brought up a little at the center of the image screen and in a large amount at the upper and the lower parts of the screen. As a result, the misconvergence can be prevented.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention is applicable to color television receivers, color cathode ray tube display devices, etc. in which six electron guns are arranged in-line and no field controller is provided inside. The present invention relates to a deflection device mounted on a color picture tube.

<Prior Art> As is well known, in a deflection device which is mounted on a color picture tube having three electron guns arranged in-line and deflects the beam generated by each electron gun, the horizontal deflection coil is used as a whole. By configuring the vertical deflection coil to have a pincushion-shaped deflection field, and by configuring the vertical deflection coil to have a barrel-shaped deflection field, and in addition, in the neck of the picture tube, a central beam and both A magnetic field control element (field controller) consisting of a combination of multiple magnetic materials that matches the deflection sensitivity of the side beam on the picture tube screen (
By incorporating a FC (hereinafter referred to as FC), the sensitivities of the three beams can be adjusted, and theoretically, misconvergence can be reduced to zero.

On the other hand, in recent years, for example, in order to obtain high-definition and high-resolution screens, the horizontal scanning frequency has been increased to the usual 15.75K.
The frequency is set high between Hz and 64KHz, but when the horizontal scanning frequency is increased in this way, eddy currents are generated in the FC, and the horizontal shift of the central beam becomes large. This also has various effects on other convergence characteristics (causing misconvergence), and as a result, it becomes extremely difficult to obtain good screen characteristics without misconvergence over the entire screen. On the other hand, in picture tubes with small neck diameters, it is structurally difficult to incorporate the FC into the neck, and the deflection device is attached to color picture tubes that do not have an FC from the beginning. Beam sensitivity cannot be adjusted, resulting in misconvergence.

Conventionally, in order to eliminate such misconvergence and obtain good screen characteristics, a color picture tube without FC in the neck is used, and the screen as shown in Fig. 6, which is caused by the absence of FC, is used. vertical axis (Y
This eliminates misconvergence, where the center beam G is insufficiently sensitive to the beams B and R located on the left and right sides of the screen (axis), and the lack of sensitivity is large at the top and bottom of the screen and small at the middle. For this purpose, as shown in FIG. 7, an auxiliary filter 32 that generates an auxiliary magnetic field for increasing (correcting) the sensitivity of the central beam G is connected in series to the vertical deflection coil 31 of the deflection yoke. Correction amount i! is applied in parallel to the coil 32! It was constructed by connecting a variable resistor 36 for lN adjustment.

<Problems to be solved by the invention> However, in such a conventional configuration, the amount (proportion) of the auxiliary magnetic field applied to the central beam G is the same at the top, bottom, and middle of the screen, and as a result, , as shown in Figure 8, even if the misconvergence of the central beam G in the upper and lower parts of the screen is eliminated, the misconvergence ratio of the central beam G in the middle part of the screen is smaller than that in the upper and lower parts.
is over-corrected for the beam $ on both sides, and there is still a problem that misconvergence cannot be resolved.

<Means for Solving the Problems> The present invention has been made to solve the above problems.
Three electron guns are arranged horizontally in a row, and the beam generated by the central electron gun is located at the rear side of the deflection yoke mounted on the color picture tube without a field controller inside. A pair of auxiliary magnetic field generating means are provided perpendicularly to the arrangement direction of the electron guns, and the auxiliary coils constituting the auxiliary magnetic field generating means are wound in the same direction. It consists of a second positive winding part, a resistor is connected in series to the first positive winding part, and a parallel circuit of the second masterpiece part is connected in series, and two diodes are connected in series to the second positive winding part for polarity. are connected in opposite directions.

Function> The auxiliary coils constituting a pair of auxiliary magnetic field generating means that add an auxiliary magnetic field to the beam generated by the central electron gun are connected to the first coil with the same winding direction. A resistor and a parallel circuit of the second positive winding part are connected in series to the first positive winding part, and two diodes are connected in series to the second positive winding part. The amount of auxiliary magnetic field generated by the auxiliary coil is controlled by the first winding portion, the value of the resistance, or the conduction or non-conduction of the diode. The misconvergence is caused by changing the amount of current flowing through the second positive winding portion, which changes between the center and the upper and lower parts of the screen, resulting in a different rate of misconvergence between the center and the upper and lower parts of the screen. This is achieved by canceling this over the entire area of the screen.

<Embodiment> Hereinafter, one embodiment of the deflection device of the present invention will be described in detail with reference to the drawings. In FIG. 1, the deflection device 10 includes a core 11
, a vertical deflection coil 12 wound toroidally around the outer periphery of the core 11 , a cross-shaped horizontal deflection filter 14 arranged on the inner surface of the core 11 via a coil bobbin 13 , and arranged on the back side of the enlarged rear part 13 a of the coil bobbin 13 A device consisting of a pair of fixed auxiliary magnetic field generating means 15 and 16, and three green and red electron guns (B, G).

R) are arranged horizontally in a line (in-line) and are mounted and fixed on the color picture tube neck portion 17 in which no FC (74-field controller) is present. Among these, the vertical deflection coil 12 generates a barrel-shaped vertical deflection magnetic field,
The horizontal deflection filter 14 generates a pincushion-shaped horizontal deflection magnetic field, as in the prior art. coil bobbin 13
The auxiliary magnetic field generating means 15.16 arranged on the rear side of the enlarged rear part 13a are each composed of a substantially U-shaped core 18.19 and an auxiliary coil 20 wound around the core 18.19, and Electron guns (B, G,
R) are arranged facing each other perpendicularly to the arrangement direction of R). As shown in FIG.
It consists of a masterpiece part 20a and a second regular part 20b, and is wound in a laminated manner around the core 18°19. The auxiliary coils 20 (20a, 20b) are connected in series with the vertical deflection coil 12 connected to the vertical deflection circuit 21, as shown in FIG. , 20b), like the vertical deflection coil 12, a sawtooth vertical deflection current flows through them. A resistor 22 is connected in parallel to the second positive winding portion 20b constituting the auxiliary coil 20 through which the vertical deflection current flows, and a resistor 22 is connected in series to the second positive winding portion 20b from a Zener diode, a shutter key diode, etc. Two diodes 23 and 24 are connected with their polarities opposite to each other, and the first positive winding part 20H is connected to the second positive winding part 20b5 from the diode 2!1.24 and the resistor 22. Parallel circuits are connected in series. Furthermore, the first auxiliary coil 20 is connected in parallel to the entire auxiliary coil 20. Second main volume part 20
A polyurethane 25 is connected to adjust the amount of current flowing to a and 20b. In FIG. 3, 26 is a volume for adjusting the amount of current flowing through the vertical deflection coil 12, and is connected in parallel to the vertical deflection coil 12 as required.

Next, the operating state of the deflection device of the present invention will be explained. The first part of the auxiliary filter 20 constituting the auxiliary magnetic field generating means 15.16. The second regular winding portions 20a, 20b are connected in series to the vertical deflection filter 12, respectively, and the second regular winding portions 20a, 20 of the auxiliary coil 20 are connected in series.
Similarly to the vertical deflection coil 12, a sawtooth wave vertical deflection current flows through b.

Along with this, the core 18. of the auxiliary magnetic field generating means 15.16.
19, an auxiliary magnetic field 1" A + as shown in FIG.
ΩB is generated, and these auxiliary magnetic fields 121A and ρB are concentrated on the green beam G generated by the electron gun (G) located centrally within the neck portion 17, and as a result, the sensitivity of the green beam G is increased. It is something. Here, the auxiliary magnetic field FiA, 93B applied to the green beam G
The amount changes depending on the value of the vertical deflection current (sawtooth current) flowing through the auxiliary coil 20. That is, above the center of the screen and at the top, the value of the vertical deflection current is close to the peak value, the diode 23 becomes conductive, and the current flows through the positive winding of the rear cylinder 2 through the first overwhelming part 20a. Part 2Oa
, the auxiliary magnetic field (?λ) according to the number of turns of 20b.

eB ) is generated and added to the green beam G. on the other hand,
In the middle of the screen, the value of the vertical deflection current is close to the minimum value (0), the diode 25 is in a non-conducting state, and the current is at the first
After passing through the positive winding part 20a, it passes through the resistor 22 side,
The auxiliary magnetic field (ρ
A, 125B) occurs.

In other words, at the top of the screen, the first. Second regular volume part 20a
, 20b, the amount of auxiliary magnetic field generated is large, and in the middle part of the screen, the amount of auxiliary magnetic field generated is small, corresponding to the number of turns only in the first positive winding part 20a, and in the upper part of the screen. In this case, the sensitivity of the green beam G in the center is greatly increased, and the sensitivity of the green beam G in the middle part of the screen is slightly increased compared to the upper part. Then, do the same thing below the center of the screen (in this case, the vertical deflection current becomes a negative component, so the diode 24 becomes non-conducting at the middle of the screen, and the diode 24 becomes conductive at the bottom of the screen). ), the amount of generated auxiliary magnetic field increases in the middle part (according to the number of auxiliary magnetic fields), and the amount of auxiliary magnetic field generated increases in the lower part (the amount of generated auxiliary magnetic field corresponds to the number of turns of the first and second regular winding parts 20a, 20b), The sensitivity of Green Beam G is slightly increased in the middle of the screen, and the sensitivity of Green Beam G is significantly increased in the lower part of the screen.

As a result, as shown in Figure 5, the green beam G is significantly corrected in the direction of the arrow at the top and bottom of the screen, and the green beam G is slightly corrected in the direction of the arrow in the middle of the screen to correct misconvergence. Finally, each beam B,
It is possible to obtain a good one-screen characteristic in which G and R match over the entire screen.

Here, by adjusting (changing) the value of the resistor 22 when the diodes 23 and 24 are conductive, the amount of current flowing through the second positive winding portion 20b can be finely adjusted. , the amount of increase in the sensitivity of the green beam G at the top and bottom of the screen can be finely adjusted.

In one embodiment of the deflection device of the present invention, two Zener diodes or Schittky diodes with opposite polarities are connected in series to the second regular winding portion of the auxiliary coil constituting the auxiliary magnetic field generating means. In the above description, the auxiliary coil is connected in series with the vertical deflection coil, but silicon diodes may also be used.In one embodiment of the deflection device of the present invention, the auxiliary coil is connected in series with the vertical deflection coil. In this example, the auxiliary coil is not connected to the vertical deflection coil, and a correction current synchronized with the vertical deflection current is separately passed through the auxiliary coil. It may be configured in this manner. Furthermore, although the deflection device of the present invention has been described in which the vertical deflection coil is wound around the core in a toroidal manner, the vertical deflection coil may be wound in a saddle shape.

<Effects of the Invention> The deflection device of the present invention is as described in detail above, and the auxiliary magnetic field generating means generates a unique auxiliary magnetic field that is unrelated to the deflection magnetic field generated by the deflection coil, and the deflection device is located at the center. The lack of sensitivity of the beam caused by the electron gun can be reduced by the necessary amount at the top, bottom, and middle of the screen, eliminating the unbalanced lack of sensitivity of the center beam at the top, bottom, and middle of the screen. With an extremely simple configuration, it is possible to obtain good image quality characteristics without misconvergence over the entire screen while maintaining the best deflection characteristics. Further, the auxiliary coil constituting the auxiliary magnetic field generating means is connected to the first coil. It is composed of the second regular winding part, and the parts where the central beam has a large amount of insufficient sensitivity (the upper and lower parts of the screen) are the first winding part. By using the second overwhelming part, only the first positive winding part is used to generate an auxiliary magnetic field for the part where the amount of insufficient sensitivity is small (middle part of the screen), reducing the total number of turns of the auxiliary coil. As a result, without adversely affecting other screen characteristics, and at low cost,
Misconvergence can be corrected. Furthermore, according to the deflection device of the present invention, a resistor is connected in parallel to the second positive winding part, and the amount of current flowing through the second positive winding part can be finely adjusted by changing the value of the resistor. With this, it is possible to make subtle adjustments to misconvergence at the top and bottom of the screen. As described above, the deflection device of the present invention produces various effects.In order to obtain a high-definition, high-resolution screen, the horizontal scanning frequency is set high, and the FC is installed inside. This device will be effective in the future as a deflection device for picture tubes that do not have the same technology.

[Brief explanation of drawings]

FIG. 1 is a schematic rear view of an embodiment of the deflection device of the present invention, and FIG. 2 is a sectional view of the auxiliary magnetic field generating means.
Fig. 3 is a wiring diagram of an auxiliary coil that also forms a part of the auxiliary magnetic field generating means, Fig. 4 is an explanatory diagram of the operation of the auxiliary magnetic field generating means, and Fig. 5 shows how the 3'lt daughter beam is converted by the deflection device of the present invention. Figure 6 is an explanatory diagram of a state in which the beam is blurred due to no FC in the neck of the picture tube. Figure 7 is a wiring diagram of an auxiliary coil that forms part of the conventional auxiliary magnetic field generation means, and Figure 8 shows the over-correction in the middle part of the screen of the central beam caused by the deflection device equipped with the conventional auxiliary magnetic field generation means. It is an explanatory diagram of a state. DESCRIPTION OF SYMBOLS 10... Deflection device, 15. 16... Auxiliary magnetic field generation means, 20... Auxiliary coil, 20a... 1st normal winding part, 20b... 2nd normal winding part, 22...・Resistance, 2
3.24...diode,

Claims (1)

[Claims] Three electron guns, blue, green, and red, are arranged horizontally in a line and are located at the rear side of the deflection yoke mounted on the color picture tube without a field controller inside. A pair of auxiliary magnetic field generating means for applying an auxiliary magnetic field to the beam generated by the electron gun are provided perpendicularly to the arrangement direction of the electron guns, and the auxiliary coil constituting the auxiliary magnetic field generating means is arranged so that the winding direction thereof is It is composed of the same first and second positive winding parts, a resistor and a parallel circuit of the second positive winding part are connected in series to the first positive winding part, and the second positive winding part is connected to the parallel circuit of the second positive winding part. A deflection device characterized in that two diodes are connected in series with their polarities in opposite directions.