JPH05190116A - Deflecting device for color picture tube - Google Patents

Abstract

PURPOSE:To correct the deflection in the turn of the luster of a center beam for the luster of a side beam. CONSTITUTION:A deflecting yoke 20 consists of a horizontal deflecting coil. and a vertical deflecting coil. Further, a pair of auxiliary magnetic field generators 21 are arranged in vertically symmetrical form with respect to a horizontal axis (X axis) at the rear edge part of the deflecting yoke 20. In this auxiliary magnetic field generators 21 in pair, a coil 23 which is connected in series with the vertical deflecting coil is wound on a core 22 having a nearly U shape, and magnetic pole forming leg parts 22a and 22b are provided, and the magnetic field genenrated on the coil 23 by the magnetic pole forming leg parts 22a and 22b is formed to a pin cushion type magnetic field. Further, a magnetic piece 26 as magnetic field adjusting means is inserted into the part between the core 22 and a flange part 25 between the magnetic pole forming leg parts 22a and 22b of the auxiliary magnetic field generator 21.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deflection device for a color picture tube, and more particularly to an improvement of an auxiliary magnetic field generating device provided at the rear end portion of the deflection device for an in-line color picture tube.

[0002]

2. Description of the Related Art In general, as shown in FIG. 7, a color picture tube device 1 has an envelope composed of a panel 2 and a funnel 3 integrally joined to the panel 2, and an inner surface of the panel 2 has an envelope. A phosphor screen 4 composed of a stripe-shaped three-color phosphor layer that emits blue, green, and red is formed, and a shadow in which a number of electron beam passage holes are formed inside the phosphor screen 4 facing the phosphor screen 4. A mask 5 is arranged. An electron gun 8 that emits three electron beams 7B, 7G, and 7R is provided in the neck 6 of the funnel 3, and the above-mentioned 3 is provided outside the funnel 3 closer to the phosphor screen 4 than the electron gun 8. A deflection yoke 9 for deflecting the electron beams 7B, 7G, 7R to scan the phosphor screen 4 horizontally and vertically is mounted.

In such a color picture tube device, the electron gun is an in-line type electron gun which emits a three electron beam consisting of a center beam and a pair of side beams arranged in a line in the first direction. From a first deflection coil that generates a pinction type deflection magnetic field that deflects the electron beam in the first direction and a second deflection coil that generates a barrel type deflection magnetic field that deflects the three electron beams in a direction orthogonal to the first direction. A self-convergence in-line type color picture tube device, which self-focuses the three electron beams arranged in a row by combining the deflection yokes described above, is widely used.
And, usually, the arrangement direction of the electron beam is the horizontal direction,
The first deflection coil is a horizontal deflection coil and the second deflection coil is a vertical deflection coil.

However, in this self-convergence type in-line color picture tube device, various screen distortions occur due to tube characteristics, tube assembly errors, and the like.

One of them is coma which occurs because the deflection sensitivity for the center beam is relatively stronger than the deflection sensitivity for the pair of side beams. That is,
In the self-convergence in-line color picture tube device, as shown in FIG. 8, the rasters 11B and 11R of the pair of side beams 7B and 7R are made to coincide with each other over the entire screen 10 as shown in FIG. The center beam 7G and the pair of side beams 7
It is difficult to match the raster 11G of the center beam 7G and the rasters 11B and 11R of the pair of side beams 7B and 7R due to the difference in deflection sensitivity between B and 7R, and the horizontal axis (X axis) end of the screen 10 and HCR, VC at the vertical axis (Y axis) end
Coma aberration indicated by R occurs.

In the usual in-line type color picture tube device, the coma aberration is corrected by magnetically coupling the beam emission end side electrode of the electron gun to the rear magnetic field of the deflection yoke and relatively deflecting the pair of side beams. It is corrected by arranging a magnetic element called a field controller, which has a function of weakening the sensitivity lower than the deflection sensitivity of the center beam. However, when the horizontal deflection frequency becomes high, convergence deviation occurs due to the AC loss of the magnetic element, so that the magnetic field of the deflection yoke itself is often used for correction without using the magnetic element. In this case, H
Since CR has a small deviation amount from the beginning, it can be corrected by the horizontal deflection coil, but VCR has a large correction amount and is difficult to correct by the vertical deflection coil.
The coma aberration as shown in was left.

Therefore, as shown in FIG. 10, the auxiliary coil 13 is wound around a pair of U-shaped cores 12, and the auxiliary coil 13 is connected in series to the vertical deflection coil. Horizontal axis (X axis) on the gun side end (rear end)
There is a means for correcting by a deflecting device which is arranged symmetrically with respect to the vertical axis and which generates a pincushion type magnetic field corresponding to a vertical deflection barrel type vertical deflection magnetic field.

[0008]

As described above, in order to correct the coma between the center beam and the pair of side beams, the auxiliary coil that generates the pincushion type magnetic field in synchronization with the vertical deflection is used. There is. However, the deviation of the center beam pattern from the pair of side beam patterns as shown in FIG. This deviation amount is, for example, 0.4 mm in a 17-inch color picture tube device, which is a size that cannot be ignored. It is difficult for the conventional auxiliary magnetic field generating device to correct the deviation of the pattern of the center beam with respect to the pattern of the pair of side beams.

The present invention has been made in order to solve such a problem, and provides a deflecting device for a color picture tube capable of correcting a deviation of a pattern of a center beam with respect to a pattern of a pair of side beams. The purpose is to do.

[0010]

In order to solve the above problems, the present invention provides a first magnetic field for deflecting three electron beams arranged in a line in a first direction in the first direction.
A deflection yoke having a deflection coil and a second deflection coil that generates a deflection magnetic field that deflects in a direction orthogonal to the first direction, and a current flowing in synchronization with the deflection by the second deflection coil flow to arrange the three electron beams. In a deflection device for a color picture tube comprising a pair of auxiliary magnetic field generators arranged substantially symmetrically with respect to an axis, the auxiliary magnetic field generator is an auxiliary coil through which a current synchronized with the deflection by the second deflection coil flows, A pair of magnetic pole forming legs for guiding the magnetic field generated by the auxiliary coil to the vicinity of the passage region of the three electron beams and shaping it into a pincushion type magnetic field in the same direction as the deflection magnetic field by the second deflection coil, and the pair of magnetic pole formation. A magnetic field adjusting means provided between the legs for adjusting the shape of the pincushion type magnetic field so as to be asymmetric with respect to the arrangement axis of the three electron beams. And correcting the deviation by adjusting the shape of the pincushion magnetic field in accordance with the deviation of the raster.

Further, the magnetic field adjusting means is composed of a movable magnetic piece so that the magnetic field shape is adjusted by changing the distance between the end of the magnetic pole forming leg and the pair of magnetic pole forming legs. And

Further, the magnetic field adjusting means comprises a coil wound around a core, and the magnetic field shape is adjusted by changing the polarity of the coil.

[0013]

When a deflection of the center beam raster occurs with respect to the pair of side beam rasters on the screen, when the deflection on the upper side of the screen is considered, it is provided between the magnetic pole forming legs of the auxiliary magnetic field generator. By magnetizing the end of the magnetic field adjusting means on the beam passage region side to a predetermined polarity, a magnetic field can be generated between the magnetic pole forming leg of the auxiliary coil and the magnetic field adjusting means. By making the direction of the force that the beam receives by this magnetic field perpendicular to the beam arrangement direction for side beams and oblique to the beam arrangement direction for center beams, the side beams are arranged in the arrangement direction. The center beam is deflected in a direction perpendicular to the beam arrangement axis in an oblique direction. As a result, the raster of the side beam only shifts in the direction perpendicular to the arrangement direction, and the phenomenon that the raster of the center beam falls can be corrected.

[0014]

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

(Example 1)

In the deflection apparatus for a color picture tube according to this embodiment, as shown in FIG. 1, a pair of auxiliary magnetic field generators 21 are arranged at the rear end of the deflection yoke 20 vertically symmetrically with respect to the horizontal axis (X axis). ing. This pair of auxiliary magnetic field generators
Each of the cores 21 has a substantially U-shaped core 22 and an auxiliary coil 23 wound around each core. The auxiliary coil 23 is connected in series to the vertical deflection coil 24 of the deflection yoke so that the vertical deflection current flows. This pair of auxiliary magnetic field generators 21
Has a pair of magnetic pole forming legs 22a and 22b extending from both ends of the core 22 in the beam arrangement axis direction.
With a and 22b, the magnetic field generated by the coil 23 is shaped into a pincushion type magnetic field in the same direction as the vertical deflection magnetic field generated by the vertical deflection coil 24 in the passage region of the three electron beams. Further, the magnetic pole forming leg 22 of the auxiliary magnetic field generator 21 is
A magnetic piece 26 is inserted as a magnetic field adjusting means between a and 22b and between the core 22 and the flange portion 25.

By the way, as described above, in order to correct the coma between the center beam and the pair of side beams, the auxiliary coil for generating the pincushion type magnetic field in synchronization with the vertical deflection is used. As shown in 11,
It is difficult for the conventional auxiliary coil to correct the misalignment of the center beam raster 11G with respect to the pair of side beam rasters 11R and 11B. Therefore, the inventor studied the cause of the deviation of the center beam raster, and the cause is considered to be as follows. That is, the convergence correction of the center beam and the side beam is usually performed by making the horizontal deflection magnetic field into a pincushion shape as a whole and the magnetic field on the electron gun side into a barrel shape. This barrel-shaped magnetic field contributes more to the deflection of the center beam than the side beams. However, when the main axis of the deflection magnetic field and the axis of the auxiliary coil are misaligned, the amount of deflection of the center beam to the left and right is different due to the difference in how the pincushion magnetic field of the auxiliary coil is applied above and below the deflection yoke. It is considered that the center beam raster falls over the beam raster.

Therefore, the correction action in the case where the center beam raster tilts with respect to the pair of side beam rasters on the screen as shown in FIG. 11 will be described below. When considering the deflection at the upper side of the screen (Y> 0), as shown in FIG. 2, the magnetic piece 26 inserted between the auxiliary magnetic field generator and the rear flange portion is moved to the left on the upper auxiliary magnetic field generator side. knock down. Then, the end of the magnetic piece 26 approaches the magnetic pole forming leg 22b that is the N pole of the core, and the end of the magnetic piece 26 on the approaching side is magnetized to the S pole. When the end of the magnetic piece 26 is magnetized to the S pole, a new magnetic field 31 is generated between the magnetic pole forming leg 22b and the end of the magnetic piece 26, and the side beam 7R is directed upward and the center beam 7G is directed upper right. Is applied, the side beam 7R is deflected upward and the center beam 7G is deflected obliquely to the upper right with respect to the beam arrangement axis (X axis). Similarly, if the magnetic piece is also tilted to the left on the side of the lower auxiliary coil, the end of the magnetic piece that has approached the magnetic pole forming leg 22c that is the S pole of the core is N
A force is applied to the side beam 7B upward and to the center beam 7G to the upper right, so that the side beam 7B is deflected upward and the center beam 7G is deflected obliquely upper right.
Therefore, the center beam raster 11G shown in FIG.
As shown in FIG. 3, only the center beam raster 11G tilts to the right and the side beam raster 11 tilts to the left.
Both R and 11B only cause a vertical shift, and as a result, the above phenomenon is corrected. At this time, the VCR changes a little, but it can be adjusted by inserting a variable resistor in parallel with the auxiliary magnetic field generator. Further, the phenomenon in which the raster of the center beam tilts to the right can be corrected by the above-described principle by adjusting the moving direction of the magnetic piece.

Considering the distance between the center beam and the side beam, it is desirable that the moving distance of the magnetic piece is such that the moving amount of the end portion is 6.6 mm or less with respect to when the magnetic piece is located at the center. According to this embodiment, the deviation amount of 0.15 mm can be made almost zero.

In the above embodiment, the magnetic piece is moved around the wound portion of the coil of the core. However, if the distance between the leg of the core of the auxiliary coil and the end of the magnetic piece is made different, the left and right sides are different. Of course, the way of moving is not limited to the above embodiment.

Regarding the pair of upper and lower auxiliary coils, the method of moving the magnetic piece is substantially symmetrical with respect to the tube axis, but when the tilting of the center beam raster is different from that of the side beam raster at the top and bottom of the screen. , The auxiliary coil on the upper side and the auxiliary coil on the lower side may adjust the moving method of the magnetic piece.

Further, although the magnetic piece is inserted between the auxiliary coil and the rear flange in this embodiment, it is possible to provide the magnetic piece on the surface of the auxiliary coil on the electron gun side.

(Example 2)

Although the movable magnetic pieces are used as the adjusting means in the above-described first and second embodiments, the present invention is not limited to this, and other adjusting means are also possible. Therefore, another embodiment will be described below.

In this embodiment, the entire structure of the deflection device for a color picture tube is the same as that of the above embodiment, and the structure of the auxiliary magnetic field generating device is different in this embodiment. That is, as shown in FIG.
1, 42 and the leg portions 41a, 41b, 41c, 42 of the cores 41, 42
It is composed of coils wound around a, 42b and 42c. Legs 41a, 41b, 42a, 42 on both sides of the E-shaped cores 41, 42
A coil 43a, 43b, 44a, 44b for generating a pincushion type magnetic field is wound around b, and two coils are wound in opposite directions on the central legs 41c, 42c. Has been done. The connection state of these coils is shown in FIG. In FIG. 5, the coils Lu1 and Ld1 are wound so that the facing portions of the leg portions 41c and 42c at the center of the upper and lower auxiliary coils have opposite polarities.
Ld2 is wound so as to be the opposite. That is, the coils Lu1 and Lu2 are wound around the leg portion 41c, and the coils Ld1 and Ld2 are wound around the leg portion 42c. The current flowing through the coils Lu1 and Ld1 and the coil Lu
It is possible to correct the phenomenon in which the raster of the center beam falls by adjusting the currents flowing in 2 and Ld2 with the variable resistor R or the differential coil.

Next, as shown in FIG. 11, the principle of operation will be described for the case where the center beam raster 11G is tilted with respect to the pair of side beam rasters 11R and 11B on the screen. When considering the deflection on the upper side of the screen, as shown in FIG. 6, by adjusting the variable resistor R shown in FIG. 5 so that the central leg portion 41c of the upper auxiliary magnetic field generator becomes the S pole at the time of upward deflection. , A magnetic field 51 from the leg portion 41b toward the leg portion 41a can be generated, and a force is applied to the side beam 7R upward and to the center beam 7G rightward,
The side beam 7R is deflected upward, and the center beam 7G is deflected upper right with respect to the oblique beam arrangement direction. Similarly, if the central leg portion 42c is the N pole on the side of the lower auxiliary magnetic field generator, a force is applied upward to the side beam 7B and an upper right direction to the center beam 7G, and the side beam 7B.
Is deflected upward and the center beam 7G is deflected obliquely to the upper right. Therefore, the left tilt phenomenon of the center beam raster shown in FIG. 11 only tilts the center beam raster to the right as shown in FIG. 3, and the rasters of the pair of side beams 7B and 7R only cause vertical displacement. As a result, the raster tilt of the center beam is corrected. At this time V
Although CR slightly changes, a variable resistor can be placed in parallel with the auxiliary coil for adjustment. Regarding the phenomenon of the center beam raster tilting to the right, the variable resistance may be adjusted so that the polarity of the center leg is opposite to the above. Further, when the variable resistance is in the center, the magnetic field generated by the coil wound around the central leg portion is canceled and no magnetic force is generated. Therefore, the auxiliary magnetic field can be adjusted by adjusting the variable resistance.

In this embodiment, the resistance value and the like can be adjusted as compared with the case where the magnetic piece is manually moved in the first embodiment.

Although the embodiment of the present invention has been described above, the structure of the present invention is not limited to the above-mentioned embodiment, and the structure of the pair of upper and lower auxiliary magnetic field generating devices is such that a pincushion magnetic field is generated near the beam passage region. It goes without saying that it may be generated.

[0029]

As described above, according to the present invention,
By providing the magnetic field adjusting means between the magnetic pole forming legs of the coil for correcting the VCR, a magnetic field is generated between the magnetic pole forming legs and the magnetic field adjusting means, and the beam deflection direction by the magnetic field is the side beam. Is orthogonal to the beam array axis, and the center beam is diagonal to the beam array axis, correcting the misalignment of the center beam raster with respect to the side beam raster. can do.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention.

FIG. 2 is a schematic diagram for explaining the operation of the embodiment shown in FIG.

FIG. 3 is a schematic diagram of a raster for explaining the effect of the embodiment shown in FIG.

FIG. 4 is a schematic view of a main part showing another embodiment of the present invention.

5 is a diagram showing a wire connection state of the coil shown in FIG.

FIG. 6 is a schematic diagram for explaining the operation of the embodiment shown in FIG.

FIG. 7 is a cross-sectional view showing a configuration of a conventional color picture tube device.

FIG. 8 is a schematic diagram showing a raster on a screen of a conventional color picture tube device.

FIG. 9 is a schematic diagram showing coma aberrations of a center beam and side beams on a screen of a conventional color picture tube device.

FIG. 10 is a perspective view showing one means for correcting coma aberration in a conventional color picture tube device.

FIG. 11 is a schematic view showing a deviation of a center beam raster in a conventional color picture tube device.

[Explanation of symbols]

7G ... Center beam 7R, 7B ... Side beam 11G ... Center beam raster 11R, 11B ... Side beam raster 20 ... Deflection yoke 20 21, 40 ... Auxiliary magnetic field generator 22, 41, 42 ... Core 22a, 22b, 41a, 41b, 41c, 42a, 42b, 42c ... Magnetic pole forming leg 23, 43a, 43b, 44a, 44b ... Coil vertical deflection coil 24 Magnetic piece 26 Lu1, Ld1, Lu2, Ld2 ... Coil

Claims (3)

[Claims] 1. A first magnetic field generating deflection magnetic field for deflecting three electron beams arranged in a line in a first direction in the first direction.
A deflection yoke having a deflection coil and a second deflection coil that generates a deflection magnetic field that deflects in a direction orthogonal to the first direction, and a current flowing in synchronization with the deflection by the second deflection coil flow to arrange the three electron beams. In a deflection device for a color picture tube, comprising a pair of auxiliary magnetic field generators arranged substantially symmetrically with respect to an axis, the auxiliary magnetic field generator is an auxiliary coil through which a current synchronized with deflection by the second deflection coil flows, A pair of magnetic pole forming legs for guiding the magnetic field generated by the auxiliary coil to the vicinity of the passage region of the three electron beams and shaping it into a pincushion type magnetic field in the same direction as the deflection magnetic field by the second deflection coil, and the pair of magnetic pole formation. A magnetic field adjusting means provided between the legs for adjusting the shape of the pincushion type magnetic field so as to be asymmetric with respect to the arrangement axis of the three electron beams. A deflection device for a color picture tube, characterized in that 2. The deflection device for a color picture tube according to claim 1, wherein the magnetic field adjusting means is composed of a movable magnetic piece. 3. The deflection device for a color picture tube according to claim 1, wherein the magnetic field adjusting means comprises a coil wound around a core.