JP2002208363A - Dynamic convergence correction device and image display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dynamic convergence correction device enabled to shorten the length of a coil, while securing sufficient convergence correction volume and driving speed, and to provide an image display device. SOLUTION: The dynamic convergence correction device 1, mounted around the neck part of a cathode ray tube, comprises a cylinder-shaped holder 2, a horizontal direction correcting coil 7, and a vertical direction correcting coil 8. Out of the sides of the horizontal direction correcting coil 7, the sides curving along a holder 2, are formed into a shape of an arc of which, the central angle of the sector, having its center on the axial line of the cylinder-shaped holder 2, is made to range between 75 deg. and 85 deg., and out of the sides of the vertical direction correcting coil 8, the sides curving along a holder 2, are formed into a shape of an arc of which, the central angle of the sector, having its center on the axial line of the cylinder-shaped holder 2, is made to range between 65 deg. and 75 deg..

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dynamic convergence correction device for convergence correction by deflecting an electron beam passing through a cathode ray tube by a magnetic field, a display device such as a computer equipped with a dynamic convergence correction device, and a television. The present invention relates to an image display device such as a John receiver.

[0002]

2. Description of the Related Art In recent years, a display device such as a computer using a cathode ray tube and an image display device such as a television receiver have been equipped with an in-line type electron gun, a barrel type vertical deflection magnetic field and a pin cushion type horizontal deflection magnetic field. The mainstream is a configuration combining a deflection yoke for generating the above. With this configuration, it is theoretically possible to substantially eliminate misconvergence. However, in reality, there are various unavoidable variations in manufacturing, such as slight differences in the shape of the windings of the deflection yoke coil and the shape of the cathode ray tube, and misconvergence occurs particularly at the periphery of the screen. Would. Therefore, convergence correction of the whole screen is performed by giving a static magnetic field distribution with a ring-shaped magnet attached to the neck of the cathode ray tube, or a plurality of U-shaped or yo-shaped magnetic cores are arranged around the neck, Static convergence correction and the like are performed in which a deflecting current is passed through a coil wound around a magnetic core to deflect an electron beam to correct convergence at the periphery of a screen. However, in recent years,
As the resolution and size of screens increase, the convergence correction accuracy must be further improved, and dynamic convergence correction, which performs convergence correction at a specified location on the screen, by adopting digital technology that has evolved rapidly. It is being done.

The prior art is disclosed in Japanese Patent Application Laid-Open No. 57-180.
No. 286 discloses an in-line color picture tube device that performs dynamic convergence correction by generating a convergence correction magnetic field using a coil wound around a magnetic core.
Further, Japanese Patent Application Laid-Open No. 5-76020 discloses a dynamic convergence correction device using an air-core coil having no magnetic core.

Hereinafter, a conventional general dynamic convergence correction device will be described with reference to the drawings.

FIG. 8A is a perspective view of a main part of a conventional dynamic convergence correction apparatus, and FIG. 8B is a side view of a main part of the conventional dynamic convergence correction apparatus. 8, reference numeral 101 denotes a conventional dynamic convergence correction device;
Reference numeral 2 denotes a cylindrical holder, and reference numeral 103 denotes a holder 102 for fixing a coil described below to the outer peripheral surface of the holder 102.
A plurality of guide pins fixed at predetermined positions substantially perpendicular to the outer peripheral surface of the holder, 104 is a holding plate provided at one end of the holder 102, 105 is a lead terminal provided at a lower end of the holding plate 104, Reference numeral 106 denotes a coil formed by an air-core coil formed by winding a conductive wire in a substantially rectangular shape, and eight coils are provided around the outer peripheral surface of the holder 2 at substantially equal intervals, and L3 denotes a long length of the holder 102 of the coil 106. The coil length, which is the length in the direction, and W2 is the coil width, which is the circumferential length of the holder 102 of the coil 106.

The dynamic convergence correction device 101 includes a coil 1 formed by a substantially rectangular air-core coil having the same shape.
06 are arranged at positions where the outer peripheral side surface of the holder 102 is divided into eight every 45 °. The coil width W2 of the coil 106 is substantially equal to a length obtained by dividing the circumferential length of the outer peripheral side surface of the holder 102 into eight, and the coil 106 is disposed so as not to overlap with an adjacent coil. Coil 10
Numeral 6 designates two sets of coil groups in which every other four coils are connected in series, and these two sets of coil groups generate quadrupole magnetic fields for horizontal direction correction and vertical direction correction, respectively.
Then, the convergence correction is performed by changing the drive current of the coil 106 in accordance with the screen scanning and generating an appropriate correction magnetic field distribution in each part of the screen.

FIG. 9 is a side view of a main part of a cathode ray tube provided with a conventional dynamic convergence correction device. In FIG.
Reference numeral 101 denotes a dynamic convergence correction device, which is the same as that described with reference to FIG. Reference numeral 107 denotes a cathode ray tube, 108 denotes a screen unit having a phosphor screen formed of a phosphor, 109 denotes an electron gun disposed at the neck side end of the cathode ray tube 107, 11
Reference numeral 0 denotes a deflection yoke mounted on a cone-side tapered portion of the cathode ray tube 107, 111 denotes a purity magnet mounted on a neck of the cathode ray tube 107, and 112 denotes a 4-pole mounted on the dynamic convergence correction device 101. magnet,
Reference numeral 113 denotes a six-pole magnet mounted around the dynamic convergence correction device 101, and reference numeral 114 denotes a static convergence correction device mounted around the neck of the cathode ray tube 107 and disposed on the cone side of the dynamic convergence correction device 101.

The dynamic convergence correction device 101 is mounted around the neck of the cathode ray tube 107, and furthermore, a quadrupole magnet 112 and a hexapole magnet 113 are mounted around the neck. The purity magnet 111 includes two ring-shaped magnets.
It generates a bipolar magnetic field and adjusts the purity so that the green display electron beam passing through the center of the neck of the cathode ray tube 107 passes through a predetermined position. The four-pole magnet 112 and the six-pole magnet 113 are a combination of two ring-shaped magnets each having a magnet disposed at a predetermined position. The four-pole magnet 112 and the six-pole magnet 113 generate a four-pole magnetic field and a six-pole magnetic field, respectively, to correct convergence of the entire image. I do. The static convergence correction device 114 is configured so that four magnets wound on a U-shaped magnetic core are disposed around the neck of the cathode ray tube 107, so that the entire image is distorted and errors at the periphery of the screen are caused. Correct convergence. Since the convergence correction performed by the 4-pole magnet 112, the 6-pole magnet 113, and the static convergence correction device 114 is uniformly performed in the screen, misconvergence remains locally, and this is corrected by the dynamic convergence correction device 101. .

The operation of the conventional dynamic convergence correction device configured as described above will be described below with reference to the drawings. The cathode ray tube 107 irradiates the phosphor screen formed on the screen unit 108 with an electron beam emitted from an electron gun 109, deflects the electron beam by a magnetic field generated by a deflection yoke 110, and performs screen scanning by sequentially scanning the screen. indicate. The deviation of the convergence of the electron beam generated at this time is corrected by the dynamic convergence correction device 101, the purity magnet 111, the quadrupole magnet 112, the hexapole magnet 113, and the static convergence correction device 114.
To correct.

In the conventional dynamic convergence correction device, an air-core coil having no magnetic core is used as a coil for generating a convergence correction magnetic field. An air-core coil has a smaller inductance than a coil using a magnetic core, and can drive the coil at a higher frequency, which is advantageous in an image display device that has been increasing the screen scanning frequency with a high definition in recent years. Has become. On the other hand, since the intensity of the generated magnetic field is smaller than that of a coil using a magnetic core, the integration time of the correction magnetic field acting on the electron beam is increased by placing the coil as close to the neck as possible and increasing the length of the coil. This compensates for the lack of magnetic field strength.

[0011]

However, the above-mentioned prior art has the following problems. (1) In order to realize a thinner image display device in the depth direction, which has been strongly desired in recent years, it is necessary to reduce the length of the neck of the cathode ray tube. If the dynamic convergence correction device is manufactured with a short length in order to reduce the length, the coil length of the coil provided in the device must be shortened, and therefore, the intensity of the convergence correction magnetic field decreases, and a sufficient correction amount cannot be obtained. Had issues. (2) Further, when the number of windings of the coil is increased to compensate for the amount of correction that has been reduced due to the shortening of the coil length of the coil provided in the dynamic convergence correction device, the inductance of the coil increases, and There is a problem that the advantage of the air-core coil that can be driven at high speed is lost.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems, and achieves a dynamic convergence correction in which a sufficient amount of convergence correction and a sufficient driving speed can be ensured, and the coil length can be reduced without lowering the convergence correction ability. It is an object of the present invention to provide a device and an image display device that can be reduced in the depth direction without lowering the convergence correction ability by using the device.

[0013]

In order to solve the above-mentioned conventional problems, a dynamic convergence correction apparatus according to the present invention uses an electron beam emitted from an electron gun provided at an end on the neck side of a cathode ray tube. Dynamic convergence correction, which circulates around the neck of the cathode ray tube and deflects the electron beam by a magnetic field to convergence correction when irradiating the phosphor disposed at the cone side end of the cathode ray tube to display an image etc. An apparatus, comprising: a cylindrical holder mounted around a neck; and an air-core coil formed by winding a conductive wire in a substantially rectangular shape curved along the side surface shape of the holder, and an outer peripheral surface of the holder. Are formed by four horizontal correction coils circumferentially provided at substantially equal intervals along with an air-core coil formed by winding a conductive wire in a substantially rectangular shape curved along the side surface shape of the holder, Outer peripheral surface of holder And four vertical correction coils circumferentially provided at substantially equal intervals along the horizontal direction correction coil, wherein the side curved along the holder among the sides of the horizontal direction correction coil is an arc, The angle of the center angle of the sector centering on the center line of the cylindrical holder of the cylindrical holder is formed to be 75 ° to 85 °, and the vertical correction coil extends along the inner holder on the side of the vertical correction coil. The curved side is an arc,
It has a configuration in which the angle of the central angle of the fan shape centering on the center line of the cylindrical holder is 65 ° to 75 °.

With this configuration, it is possible to apply a strong correction magnetic field to the electron beam for displaying blue and red while suppressing an increase in inductance, and to ensure a sufficient amount of convergence correction and a sufficient driving speed, thereby achieving convergence. Provided is a dynamic convergence correction device capable of shortening the length of a side provided in a longitudinal direction of a holder, that is, a coil length, of a side of a vertical direction correction coil without reducing a correction ability. be able to.

In order to solve the above-mentioned conventional problems,
The dynamic convergence correction device of the present invention irradiates an electron beam emitted from an electron gun provided at an end on a neck side of a cathode ray tube to a phosphor provided at an end on a cone side of the cathode ray tube. When displaying an image or the like, a dynamic convergence correction device that is mounted around the neck of the cathode ray tube and deflects the electron beam by a magnetic field to perform convergence correction,
It is formed by a cylindrical holder mounted around the neck and an air-core coil formed by winding a conducting wire in a substantially rectangular shape curved along the side surface shape of the holder, and substantially along the outer peripheral surface of the holder. Four horizontal correction coils arranged at intervals,
Four vertical corrections formed by air-core coils formed by winding conductors in a substantially rectangular shape curved along the side surface shape of the holder, and provided at substantially equal intervals along the outer peripheral surface of the holder And at least a part of the sides of the sides of the horizontal direction correction coil and the vertical direction correction coil that are curved along the holder are further outwardly curved and formed from the outer peripheral surface of the holder. It has a configuration.

With this configuration, the magnetic field components formed in the horizontal and vertical directions by the curved and protruding portions of the sides formed along the holders of the horizontal correction coil and the vertical correction coil are curved. The dynamic convergence correction device can be provided which can increase the magnetic field strength of the convergence correction and improve the convergence correction capability without reducing the convergence correction capability.

Further, in order to solve the above conventional problems,
An image display device provided with the dynamic convergence correction device of the present invention is configured such that an electron beam emitted from an electron gun disposed at a neck side end of a cathode ray tube is disposed at a cone side end of a cathode ray tube. When irradiating the phosphor to display images etc.,
A dynamic convergence correction device mounted on the neck of a cathode ray tube and deflecting an electron beam by a magnetic field to perform convergence correction, comprising a cylindrical holder mounted on the neck, and a substantially curved shape along the side surface shape of the holder. Four horizontal correction coils formed by air-core coils formed by winding a conducting wire in a rectangular shape and provided at substantially equal intervals along the outer peripheral surface of the holder, and along the side surface shape of the holder And four vertical direction correction coils formed by air-core coils formed by winding conductive wires in a substantially rectangular shape that is curved, and provided at substantially equal intervals along the outer peripheral surface of the holder. The horizontal correction coil has an arc of a side curved along the holder among the sides of the horizontal correction coil, and the angle of the central angle of the sector centering on the center line of the cylindrical holder is 75 ° or more. 85 °
The vertical correction coil is formed so that the curved side along the holder among the sides of the vertical correction coil is an arc, and the central angle of the sector centered on the center line of the cylindrical holder. The dynamic convergence correction device is characterized in that the angle is set to 65 ° to 75 °.

With this configuration, it is possible to apply a strong correction magnetic field to the electron beam for displaying blue and red while suppressing an increase in inductance, and to shorten the coil length without lowering the convergence correction ability. Since the dynamic convergence correction device is provided, the length of the holder in the longitudinal direction can be shortened, and the neck of the cathode ray tube in which the holder is mounted can be shortened. An image display device that can be reduced in thickness can be provided.

In order to solve the above-mentioned conventional problems,
An image display device provided with the dynamic convergence correction device of the present invention is configured such that an electron beam emitted from an electron gun disposed at a neck side end of a cathode ray tube is disposed at a cone side end of a cathode ray tube. When irradiating the phosphor to display images etc.,
A dynamic convergence correction device mounted on the neck of a cathode ray tube and deflecting an electron beam by a magnetic field to perform convergence correction, comprising a cylindrical holder mounted on the neck, and a substantially curved shape along the side surface shape of the holder. Four horizontal correction coils formed by air-core coils formed by winding a conducting wire in a rectangular shape and provided at substantially equal intervals along the outer peripheral surface of the holder, and along the side surface shape of the holder And four vertical direction correction coils formed by air-core coils formed by winding conductive wires in a substantially rectangular shape that is curved, and provided at substantially equal intervals along the outer peripheral surface of the holder. Wherein at least a part of the side curved along the holder among the sides of the horizontal direction correction coil and the vertical direction correction coil is further curved outward and formed so as to protrude from the outer peripheral surface of the holder. Comba And it has a configuration with a Jens correction device.

With this configuration, the magnetic field component generated in the horizontal or vertical direction by the circumferential winding of the coil holder increases,
The magnetic field strength of the convergence correction is improved, the magnetic field strength of the convergence correction ability is improved, and a dynamic convergence correction device that can be shortened without lowering the convergence correction ability is provided. Since the length in the longitudinal direction can be reduced, and the neck of the cathode ray tube in which the holder is mounted can be reduced, an image display device that can be reduced in thickness can be provided.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A dynamic convergence correction apparatus according to a first aspect of the present invention is configured to convert an electron beam emitted from an electron gun disposed at a neck end of a cathode ray tube into a cone side of the cathode ray tube. A dynamic convergence correction device that circulates around a neck of a cathode ray tube and deflects an electron beam by a magnetic field to perform convergence correction when irradiating a phosphor disposed at an end to display an image or the like, Formed by a cylindrical holder that is mounted around the holder, and an air-core coil formed by winding a conductive wire in a substantially rectangular shape curved along the side shape of the holder, and at substantially equal intervals along the outer peripheral surface of the holder. Are formed by four horizontal correction coils provided around the holder, and an air-core coil formed by winding a conductive wire in a substantially rectangular shape curved along the side surface shape of the holder, along the outer peripheral surface of the holder. At approximately equal intervals And four vertical correction coils,
The horizontal direction correction coil has an arc of a side curved along the holder among the sides of the horizontal direction correction coil, and an angle of a central angle of a sector around a cylinder center line of the cylindrical holder is 75. ° to 85 °, the vertical direction correction coil is an arc of a side curved along the holder among the sides of the vertical direction correction coil, and centered on the cylinder center line of the cylindrical holder. It has a configuration in which the angle of the central angle of the sector is 65 ° to 75 °.

With this configuration, even when the lengths of the long horizontal correction coil and the vertical correction coil in the long direction of the holder are reduced, the coil area of the horizontal correction coil and the vertical correction coil is reduced. Can be prevented from being reduced, and it is not necessary to increase the number of windings of the conductors forming the horizontal correction coil and the vertical correction coil, so that an increase in inductance is suppressed and convergence inside the holder is suppressed. The distribution of the correction magnetic field can be optimized, and a strong convergence correction magnetic field is generated at the passing position where the electron beam for displaying blue and red passes, and the electron beam for displaying blue and red is deflected and sufficient convergence is achieved. This has the effect that correction can be performed.

According to the second aspect of the present invention, an electron beam emitted from an electron gun disposed at the neck side end of the cathode ray tube is disposed at the cone side end of the cathode ray tube. A dynamic convergence correction device that is wrapped around the neck of a cathode ray tube and deflects an electron beam by a magnetic field to perform convergence correction when irradiating a phosphor to display an image or the like. And an air-core coil formed by winding a conductive wire in a substantially rectangular shape curved along the side surface shape of the holder, and four coils provided at substantially equal intervals along the outer peripheral surface of the holder And a hollow core coil formed by winding a conducting wire in a substantially rectangular shape curved along the side surface shape of the holder, and is provided at substantially equal intervals along the outer peripheral surface of the holder. Four vertical correction coils And a configuration in which at least a part of the side curved along the holder among the sides of the horizontal correction coil and the vertical correction coil is further curved outward and protrudes from the outer peripheral surface of the holder. are doing.

With this configuration, the direction of the deflection current passing through a portion of the sides of the horizontal correction coil and the vertical correction coil that protrudes outside the side formed by bending along the holder is changed, and the convergence correction magnetic field is changed. Is changed, the components of the convergence correction magnetic field in the horizontal direction and the vertical direction at the passing position where the electron beams for displaying blue and red pass are increased, and even when the coil length is shortened, the blue And an electron beam for displaying red is deflected to perform sufficient convergence correction.

According to a third aspect of the present invention, there is provided the dynamic convergence correcting apparatus according to the first aspect, wherein the dynamic convergence correcting device is curved along the inner holder on the sides of the horizontal direction correcting coil and the vertical direction correcting coil. At least a part of the side is further curved outward and formed so as to protrude from the outer peripheral surface of the holder.

With this configuration, in addition to the function of the first aspect,
The direction of the deflection current passing through the part of the sides of the horizontal correction coil and the vertical correction coil that protrudes outside the side formed by bending along the holder changes, and the distribution of the convergence correction magnetic field changes. Electrons that display blue and red even when the length of the coil is shortened by increasing the components of the convergence correction magnetic field in the horizontal and vertical directions at the passage position where the electron beams for displaying blue and red pass. This has the effect that the beam is deflected and sufficient convergence correction can be performed.

According to a fourth aspect of the present invention, there is provided the dynamic convergence correction apparatus according to any one of the first to third aspects, wherein the length of the holder is set within the side of the vertical correction coil. The length of the side provided in the length direction is longer than the length of the side provided in the length direction of the holder among the sides of the horizontal correction coil.

With this configuration, in addition to the function of any one of claims 1 to 3, the following function is provided. (1) Due to the difference in the magnetic field distribution between the horizontal correction magnetic field and the vertical correction magnetic field, the vertical convergence correction amount acting on the same electron beam under the same coil shape is smaller than the horizontal convergence correction amount. By making the coil length of the direction correction coil longer than the coil length of the horizontal direction correction coil, even if the number of windings of the conductors forming the horizontal direction correction coil and the vertical direction correction coil is the same, The horizontal convergence correction amount by the direction correction coil can be made the same as the vertical convergence correction amount by the vertical correction coil. (2) Each coil can be arranged so that each side of the horizontal direction correction coil and the vertical direction correction coil formed in the circumferential direction of the holder does not overlap, thereby preventing the coil shape from being disturbed due to thickening of the coil. Can be.

According to a fifth aspect of the present invention, there is provided the dynamic convergence correction apparatus according to any one of the first to fourth aspects, wherein at least a part of one end of the holder is directed outward. It has a configuration in which a chamfered portion chamfered in an inclined shape is formed.

According to this configuration, in addition to the function of any one of the first to fourth aspects, when the horizontal direction correction coil and the vertical direction correction coil are wound around the outer peripheral surface of the holder and arranged, The conductors forming the direction correction coil and the vertical direction correction coil can be prevented from being caught on the end of the holder, and the accuracy of the winding can be improved.

The image display device provided with the dynamic convergence correction device according to claim 6 of the present invention is characterized by claim 1 to claim 5.
The dynamic convergence correction device according to any one of the above items is provided.

With this configuration, the length of the holder for the horizontal direction correction coil and the vertical direction correction coil in the long direction can be reduced, and accordingly, the length of the holder in the long direction can be reduced. Therefore, the neck of the cathode ray tube on which the holder is mounted can be shortened, so that the image display device can be made thinner.

An embodiment of the present invention will be described below.

(Embodiment 1) FIG. 1A is a perspective view of a main part of a dynamic convergence correction apparatus according to the first embodiment, and FIG. 1B is a main part of the dynamic convergence correction apparatus according to the first embodiment. It is a side view. In the figure, reference numeral 1 denotes a dynamic convergence correction device according to the first embodiment, 2 denotes a holder which is formed in a cylindrical shape and is fitted around a neck of a cathode ray tube,
Reference numeral 3 denotes a chamfered portion formed by chamfering one end of the holder 2 toward the outside in a slant shape. Reference numeral 4 denotes a predetermined coil for horizontal direction correction and a coil for vertical direction correction along the outer peripheral surface of the holder 2. And a guide pin 5 fixed substantially perpendicularly to the outer peripheral surface of the holder 2 to be disposed at the position of the holder 2, and a holder 2 at the other end opposite to the one end where the chamfered portion 3 of the holder 2 is formed.
Holding plate 6 arranged substantially perpendicular to the longitudinal direction of
Is a lead terminal disposed at the lower end of the holding plate 5; 7 is a horizontal correction coil formed of an air-core coil, four of which are provided at substantially equal intervals along the outer peripheral surface of the holder 2; A vertical direction correction coil L formed of air-core coils and provided at substantially equal intervals along the outer peripheral surface of the holder 2, L
1 is the length of the holder 2 in the longitudinal direction.

The holder 2 and the holding plate 5 are formed of a non-conductive and non-magnetic material such as a synthetic resin, and have an opening of the cylindrical holder 2 and a holding plate 4 which are formed in a cylindrical shape so as to be installed around the neck of the cathode ray tube. Are fitted and formed so that the through-holes through which the necks are provided coincide with each other. A plurality of guide pins 4 are provided at predetermined positions on the outer peripheral surface of the holder 2, and the guide wires 4 are hooked with the wires of the horizontal correction coil 7 and the vertical correction coil 8, so that four guide pins 4 are provided.
Are wound in a rectangular shape having the vertex as a vertex to form the horizontal correction coil 7 and the vertical correction coil 8.

The chamfered portion 3 is formed by chamfering one end of the holder 2 outward. Thereby, the conductors of the horizontal direction correction coil 7 and the vertical direction correction coil 8 are hung on the guide pins 4 and wound, and the holder is used when the horizontal direction correction coil 7 and the vertical direction correction coil 8 are formed. 2 can be prevented from being caught by the conducting wire at the end of the holder 2, resulting in defective winding or disturbed coil shape, and the distribution of the convergence correction magnetic field generated inside the holder 2 can be prevented from being disturbed. The accuracy of the correction and the productivity in manufacturing the dynamic convergence correction device can be improved.

The horizontal correction coil 7 and the vertical correction coil 8 are each formed by electrically connecting four coils of the same shape in series, and the horizontal correction coil 7
The two terminals of each of the two coil groups of the vertical direction correction coil 8 are electrically connected to a lead terminal 6 provided at the lower end of the holding plate 5 by soldering or the like, and an image is displayed via the lead terminal 6. It is connected to an external coil drive circuit provided in the device or the like. The four coils of the horizontal direction correction coil 7 and the vertical direction correction coil 8 are provided around the holder 2 at substantially 90 ° intervals in the circumferential direction. They are arranged at equal intervals.

The horizontal correction coil 7 and the vertical correction coil 8 are both attached to the holder 2 along the outer peripheral surface.
The holder is arranged such that the winding direction of the coil is substantially parallel to the outer peripheral surface of the holder 2. Further, the coil length of the vertical direction correction coil 8 is formed to be slightly longer than the coil length of the horizontal direction correction coil 7.

Thus, the horizontal correction coil 7 and the vertical correction coil 8 formed in the circumferential direction of the holder 2 are formed.
Each coil can be arranged so that each side of the coil does not overlap, and by preventing the coil shape from being disturbed due to the winding of the coil, the accuracy of the coil shape can be improved and the variation in the correction magnetic field distribution can be reduced.

In the first embodiment, the magnetic field lines are generated by the vertical correction coil 8 in the overlapping portion of the horizontal correction coil 7 and the vertical correction coil 8, that is, inside the horizontal correction coil 7. The portion or the portion in which the magnetic field lines are generated by the horizontal correction coil 7 inside the vertical correction coil 8 is formed to have the same area. As a result, the magnetic field lines of the convergence correction magnetic field generated by the overlapped coils pass through any one of the horizontal correction coil 7 and the vertical correction coil 8 to generate a mutual induced electromotive force. Is canceled when the inside of the coil is summed up, it is possible to suppress the generation of the mutual induced electromotive force generated by one of the horizontal correction coil 7 or the vertical correction coil 8 and the other, and the horizontal correction coil 7 The vertical correction coil 8 can be driven independently.

The operation of the dynamic convergence correction device according to the first embodiment configured as described above will be described below with reference to the drawings. First, the convergence correction operation of the electron beam by the horizontal correction coil 7 and the vertical correction coil 8 will be described.

FIG. 2A shows the dynamic convergence correction device according to the first embodiment viewed from the cross section of the holder.
FIG. 2B is an explanatory diagram showing magnetic lines of force generated by a horizontal correction coil and deflection of an electron beam. FIG. 2B is a vertical view of the dynamic convergence correction device according to the first embodiment viewed from a cross-sectional direction of a holder. FIG. 3 is an explanatory diagram illustrating magnetic lines of force generated by a direction correcting coil and deflection of an electron beam. In FIG. 2A, the guide pin 4, the holding plate 5,
The lead terminal 6 and the vertical direction correction coil 8 are not shown, and in FIG. 2B, the guide pin 4, the holding plate 5,
The lead terminal 6 and the horizontal direction correction coil 7 are not shown.

In FIGS. 2A and 2B, reference numeral 2 denotes a holder, 7 denotes a horizontal correction coil, and 8 denotes a vertical correction coil, which are the same as those shown in FIG. And the description is omitted. B, G, and R are electron beams for displaying blue, green, and red, respectively, M1, M2
Are the directions of the lines of magnetic force of the correction magnetic field generated inside the holder 2 by the horizontal correction coil 7 and the vertical correction coil 8, respectively, and F1, F2, F3 and F4 are the electron beams B and R for displaying blue and red. Shows the deflection direction.

FIG. 3 is a block diagram of a circuit for driving the dynamic convergence correction device. In FIG.
9 is a timing circuit, 10 is a microcomputer,
Reference numeral 11 denotes a memory, 12 denotes a digital / analog converter (hereinafter referred to as a D / A converter), and 13 denotes an amplifier circuit. In the first embodiment, a digital circuit is used for driving the coil.

As shown in FIG. 3, the operation of the circuit for driving the dynamic convergence correction device 1 is as follows. First, a horizontal synchronizing signal and a vertical synchronizing signal produced at the time of screen scanning are fetched into a timing circuit 9 and these are inputted to a microcomputer 1
At 0, an address signal corresponding to the position on the screen is created and transmitted to the memory 11. The convergence correction data at each position on the screen is stored in the memory 11 in advance, and the correction data is extracted according to the received address signal and transmitted to the D / A converter 12. The D / A converter 12 converts the correction data into an actual coil drive signal, amplifies the signal by an amplifier circuit 13, and supplies a coil drive current to the horizontal correction coil 7 and the vertical correction coil 8.

The coil driving current is changed to the horizontal correction coil 7.
2A, a convergence correction magnetic field is generated in the direction of M1 or in the direction opposite to M1, as shown in FIG. 2A, whereby the blue and red electron beams are horizontally oriented in directions of F1 and F2, respectively. , Or F1 and F2, and convergence correction in the horizontal direction is performed. Further, when the coil drive current flows through the vertical correction coil 8, a convergence correction magnetic field is generated in the direction of M2 or in the opposite direction as shown in FIG. In this case, the light is deflected in the directions of F3 and F4 or in the opposite directions, and convergence correction in the vertical direction is performed.

As described above, the convergence correction is performed for each scan of the image display based on the misconvergence amount previously measured locally on the screen. In the present embodiment, the widths of the horizontal correction coil 7 and the vertical correction coil 8, that is, the sides of the horizontal correction coil 7 and the vertical correction coil 8 formed in the circumferential direction of the holder are referred to. The angles of the central angles of the fan-shape centered on the cylinder center line of the holder are 75 ° to 85 ° and 65 ° to 75 °, respectively.
°.

Here, the sides of the horizontal correction coil 7 and the vertical correction coil 8 formed in the circumferential direction of the holder are defined as arcs, and the angle of the central angle of the sector centered on the center line of the cylinder of the holder is as follows. This will be described below with reference to the drawings. FIG. 4 is an explanatory diagram showing the relationship between the holder and the horizontal direction correction coil and the vertical direction correction coil when the dynamic convergence correction device according to the first embodiment is viewed from the cross-sectional direction of the holder. In FIG. 4, the guide pins 4, the holding plate 5, and the lead terminals 6 are not shown.

In FIG. 4, reference numeral 2 denotes a holder, reference numeral 7 denotes a horizontal correction coil, and reference numeral 8 denotes a vertical correction coil, which are the same as those shown in FIG. Is omitted. A1 is the angle of the central angle of a sector with the side of the horizontal correction coil 7 formed in the circumferential direction of the holder 2 as an arc and the center of the cylindrical center line of the cylindrical holder 2 as the center.
Numeral 2 is the angle of the central angle of a sector centered on the center line of the cylindrical holder 2 with the arc of the side of the vertical correction coil 8 formed in the circumferential direction of the holder 2.

In FIG. 4, the thicknesses of the holder 2, the horizontal correction coil 7, and the vertical correction coil 8 are not described, and the holder 2, the horizontal correction coil 7, and the vertical correction coil 8 are not shown. The horizontal direction correction coil 7 and the vertical direction correction coil 8 are actually provided along the outer peripheral surface of the holder 2.

FIG. 5A is a relationship diagram showing how the correction magnetic field intensity changes when the magnitude of A1 is changed in the horizontal direction correction coil 7, and FIG. FIG. 9 is a relationship diagram showing a state of change in the correction magnetic field intensity when the magnitude of A2 is changed in the correction coil 8. In FIG. 5A, W1 is the distance between the magnetic field strength measurement position inside the holder 2 and the center of the holder 2, and the vertical axis is B or R of the convergence correction magnetic field generated inside the holder 2. The maximum value of the magnetic field intensity at the electron beam passage position is represented by a relative value based on the case where A1 is 45 °, and the horizontal axis is the magnitude of the angle A1 shown in FIG. In FIG. 5B, W1 is the distance between the magnetic field strength measurement position inside the holder 2 and the center of the holder 2, and the vertical axis is B or B of the convergence correction magnetic field generated inside the holder 2. The maximum value of the magnetic field intensity at the electron beam passing position of R is represented by a relative value based on the case where A2 is 45 °, and the horizontal axis represents the angle A shown in FIG.
2 size. 5A and 5B, FIG.
The measurement results obtained by measuring the change in the magnetic field intensity when the angles A1 and A2 are arbitrarily changed are shown.

The measurement conditions were as follows: the outer diameter of the holder 2 was 31
mm, the length L1 of the holder 2 is 18 mm, the number of coil turns of the horizontal correction coil 7 and the vertical correction coil 8 is 10 turns, and the length of the holder 2 of the horizontal correction coil 7 in the long direction is: The length of the holder 2 of the vertical correction coil 8 in the longitudinal direction is 16 mm, and the drive current of the horizontal correction coil 7 and the vertical correction coil 8 is 100 mA.

Although the electron beam passing positions of the electron beams B and R are slightly different depending on the manufacturer and the model, when the diameter of the neck of the cathode ray tube is φ, the distance from the center of the neck is almost φ. / 4 to 2φ / 3.

In this embodiment, the diameter is 3
Assuming a neck of 0 mm, the electron beam passing positions of the electron beams B and R are within a range of 4 mm to 10 mm from the center of the neck, that is, the center of the holder. Therefore, the measurement of the magnetic field strength is performed at three points of the distance W1 from the center of the holder, that is, 4 mm, 7 mm, and 10 mm.

According to the measurement results shown in FIG. 5, the convergence correction magnetic field strength generated by the horizontal correction coil 7 and the vertical correction coil 8 indicates that the angle A1 of the horizontal correction coil 7 is 75 ° to 85 °. In the vertical direction correction coil 8, the angle A2 is 6
In the range of 5 ° to 75 °, each becomes the maximum. In addition,
If the widths of the horizontal direction correction coil 7 and the vertical direction correction coil 8 are defined by the angles A1 and A2, even if the diameter of the neck increases or decreases, the width of the coil relatively changes with the increase or decrease. 7 and the distribution shape of the convergence correction magnetic field generated by the vertical correction coil 8 do not change. Therefore, the result of FIG. 5 holds regardless of the diameter of the neck, and under this condition, the strength of the convergence correction magnetic field is maximized.

(Comparative Example 1) The side of the horizontal correction coil formed in the circumferential direction of the holder 2 is set as an arc, and the angle of the central angle of the sector centered on the center line of the cylindrical holder is set to 80 °. The side of the vertical direction correction coil 8 formed in the circumferential direction of the holder 2 is set as an arc, and the angle of the central angle of the sector centered on the cylinder center line of the cylindrical holder 2 is set to 70 °, and other conditions are shown in FIG. The dynamic convergence correction device according to the first embodiment manufactured under the same measurement conditions as the measurement shown in FIG. 1 and the center of the cylindrical holder with the side of the horizontal correction coil formed in the circumferential direction of the holder 2 as an arc The angle of the central angle of the sector centered on the line is 45 °, the arc of the side of the vertical direction correction coil 8 formed in the circumferential direction of the holder 2 is the sector centered on the cylinder center line of the cylindrical holder 2. 45 ° central angle
A conventional dynamic convergence correction device as shown in FIG. 8 manufactured under the same conditions as those of the measurement shown in FIG. 5 was mounted around the neck of a 19-inch cathode ray tube. The magnetic field strength was measured by the above-mentioned measuring method.

As a result of the measurement, the dynamic convergence correction device according to the first embodiment increases the horizontal convergence correction amount by about 60% and the vertical convergence correction amount by about 60% as compared with the conventional dynamic convergence correction device. It increased by 50%.

(Comparative Example 2) The length of the side of the coil for correcting the horizontal direction in the long direction of the holder was about 14 mm, and the length of the side of the coil for the vertical direction in the long direction of the holder was about 18 mm.
The dynamic convergence correction device according to the first embodiment manufactured under the same conditions as those of the measurement shown in FIG. 5 and the length of the side of the horizontal correction coil in the long direction of the holder was set to about The conventional vertical correction coil shown in FIG. 8 was manufactured by setting the length of the side of the coil for vertical direction correction in the long direction of the holder to about 25 mm and setting other conditions to be the same as the measurement conditions of the measurement shown in FIG. Each of the dynamic convergence correction devices was mounted around the neck of a 19-inch type cathode ray tube, and the magnetic field intensity was measured by the above-described measurement method.

As a result of the measurement, the dynamic convergence correction apparatus according to the first embodiment has a convergence correction amount equivalent to that of the conventional dynamic convergence correction apparatus. At this time, the difference between the inductance of the horizontal direction correction coil and the inductance of the vertical direction correction coil of the dynamic convergence correction device in the first embodiment and the conventional dynamic convergence correction device is within 3%, and both of them have high frequency characteristics. No difference could be confirmed. This allows
The dynamic convergence correction device according to the first embodiment reduces the coil length to at least two-thirds of the conventional dynamic convergence correction device without reducing the convergence correction capability equivalent to that of the conventional dynamic convergence correction device. be able to.

As described above, the dynamic convergence correction device according to the first embodiment uses the convergence correction magnetic field distribution generated by the horizontal correction coil 7 and the vertical correction coil 8 at the positions where the B and R electron beams pass. Since the magnetic field strength can be optimized to be maximum and the length of the coil can be reduced without reducing the amount of convergence correction, the length of the dynamic convergence correction device can be reduced, and The convergence correction has the effect of preventing variations in the magnetic field distribution.

(Embodiment 2) FIG. 6A is a perspective view of a main part of a dynamic convergence correction apparatus according to a second embodiment, and FIG. 6B is a main part of the dynamic convergence correction apparatus according to the second embodiment. It is a side view.

In FIG. 6, 3 is a chamfered portion, 4 is a guide pin, 5 is a holding plate, and 6 is a lead terminal. Is omitted. 1a is a dynamic convergence correction device according to the second embodiment, 14 is a holder, 15 is a horizontal correction coil, 16 is a vertical correction coil, and 17 is an end of the holder 14 on the side where the holding plate 5 is provided. A plurality of protrusions are provided around the periphery, and 18 is a horizontal direction correction coil 1 described later.
5 and a part of the conducting wire of the vertical direction correcting coil 16, which is a curved conducting portion provided to project along the projection 17 from the outer peripheral surface of the holder 14. D1 is the height from the outer peripheral surface of the holder 14 of the curved conductor 18 described later.

The horizontal correction coil 15 and the vertical correction coil 16 are arranged so as not to overlap with each other. The holder 14 is provided with a plurality of protrusions 17 at the end on the side where the holding plate 5 is provided, whereby the horizontal correction coil 15 and the vertical correction coil 15 are provided along the outer peripheral surface of the holder 14. A part of the winding part of the use coil 16 can be formed by curving outward.

The dynamic convergence correction apparatus according to the second embodiment configured as described above will be described below with reference to the drawings as an example of a change in the convergence correction magnetic field in the vertical direction. The convergence correction operation according to the second embodiment is the same as the convergence correction operation according to the first embodiment. However, in the second embodiment, since the projection 17 is provided, the vertical The direction of the deflection current flowing through the curved portion along the projection 17 changes outward. Hereinafter, the change in the vertical correction magnetic field due to the change in the direction of the deflection current will be described.

FIG. 7A is an explanatory diagram showing a coil shape of the holder of the dynamic convergence correction device according to the second embodiment as viewed from the cross-sectional direction, and FIG. 7B is a conventional dynamic convergence correction device as shown in FIG. FIG. 4 is an explanatory view showing a coil shape of the holder viewed from a cross-sectional direction.

In FIG. 7A, 14 is a holder, D1
Denotes curved conductors, which are the same as those described with reference to FIG. 6, and thus are denoted by the same reference numerals and description thereof will be omitted.
Reference numeral 18 denotes a curved conducting wire portion which is a portion curved along the protrusion 17 of the vertical direction correction coil 16, R denotes an electron beam for displaying red, Ia denotes a deflection current flowing through the curved conducting wire portion 18, H
ax indicates that the deflection current Ia is equal to the electron beam R inside the holder 14.
Is a vertical-direction correction magnetic field component created at the passing position.

In FIG. 7B, reference numeral 19 denotes a conductor which is a portion of the coil holder provided in the conventional dynamic convergence correction device along the circumferential direction of the coil holder, 20 denotes the holder, and R denotes the electron beam for displaying red. , Ib are deflection currents flowing through the conductor 19, and Hbx is a vertical correction magnetic field component generated by the deflection current Ib at the position where the electron beam R passes inside the holder 14.

As shown in FIG. 7A, the direction of the deflection current Ia flowing through the curved conductor 18 curved along the projection 17 is along the projection 17 as shown in FIG. Compared to the direction of the deflection current Ib flowing through the uncurved conductor portion 19, the deflection current changes radially outward of the holder, and the current Ia causes the vertical correction magnetic field component H generated inside the holder 14.
ax is greater than the vertical correction magnetic field component Hbx generated by the current Ib inside the holder 14.

(Comparative Example 3) The outer diameter of the holder 14 was 31 mm
And the length L2 of the coil is 20 mm,
The dynamic convergence correction device according to the second embodiment in which the height D1 of the coil 8 is 4 mm and the conventional dynamic convergence correction device as shown in FIG. The cathode ray tube was mounted around the neck, and the magnetic field intensity was measured by the measurement method described in the first embodiment.

As a result of the measurement, the dynamic convergence correction device according to the second embodiment increases the horizontal convergence correction amount by about 10% and the vertical convergence correction amount by about 10% as compared with the conventional dynamic convergence correction device. It increased by 8%.

(Comparative Example 4) The present embodiment in which the length of the side of the horizontal correction coil in the long direction of the holder and the length of the side of the vertical correction coil in the long direction of the holder were each set to about 20 mm. In the dynamic convergence correction device according to the second aspect, the length of the side of the coil for correcting the horizontal direction in the long direction of the holder is about 23 mm, and the length of the side of the coil for vertical direction in the long direction of the holder is about 22 mm. Each of the conventional dynamic convergence correction devices as shown in FIG. 8 was mounted around the neck of a 19-inch cathode ray tube, and the magnetic field intensity was measured by the measurement method of the first embodiment.

As a result of the measurement, the dynamic convergence correction device according to the second embodiment had a convergence correction amount equivalent to that of the conventional dynamic convergence correction device. At this time, the difference between the inductance of the horizontal direction correction coil and the inductance of the vertical direction correction coil of the dynamic convergence correction device according to the second embodiment and the conventional dynamic convergence correction device is within 2%, and both have a high frequency characteristic. No difference could be confirmed.

As described above, the dynamic convergence correction device according to the second embodiment is configured, so that the coil length can be reduced by at least 10% without reducing the convergence correction capability equivalent to that of the conventional dynamic convergence correction device. It has the effect of being able to be converted.

The dynamic convergence correction device according to the first embodiment and the dynamic convergence correction device according to the second embodiment can be manufactured together.
In this case, the dynamic convergence correction device can be further reduced in size.

[0075]

As described above, according to the dynamic convergence correcting apparatus and the image forming apparatus having the dynamic convergence correcting apparatus of the present invention, the following advantageous effects can be obtained.

According to the first aspect of the present invention,
To prevent the coil area of the horizontal correction coil and the vertical correction coil from being reduced even if the length of the horizontal correction coil and the vertical correction coil in the long direction of the holder is shortened. It is not necessary to increase the number of windings of the conductors forming the horizontal correction coil and vertical correction coil, which suppresses the increase in inductance and optimizes the distribution of the convergence correction magnetic field inside the holder. Since a strong convergence correction magnetic field can be generated at a passing position where the electron beam for displaying blue and red passes, and the electron beam for displaying blue and red can be deflected, the size can be reduced. A dynamic convergence correction device can be provided.

According to the second aspect of the present invention,
The direction of the current passing through the outwardly protruding portions of the sides of the horizontal correction coil and the vertical correction coil changes, the distribution of the convergence correction magnetic field changes, and the electron beams for displaying blue and red pass. It is possible to provide a dynamic convergence correction device which can increase the horizontal and vertical convergence correction magnetic fields at the passage position and has excellent correction capability.

According to the third aspect of the present invention,
In addition to the effects of claim 1, the direction of the current passing through a portion of the sides of the horizontal direction correction coil and the vertical direction correction coil that protrudes outward changes, and the distribution of the convergence correction magnetic field changes to change the blue and red colors. It is possible to provide a dynamic convergence correction device which is capable of increasing the horizontal and vertical convergence correction magnetic fields at a passage position where an electron beam for display passes, and which has excellent correction ability.

According to the invention described in claim 4 of the present invention,
In addition to the effects of any one of claims 1 to 3, the following effects are provided. (1) Even if the number of turns of the conductors forming the horizontal direction correction coil and the vertical direction correction coil is the same, the horizontal convergence correction amount by the horizontal direction correction coil can be changed in the vertical direction by the vertical direction correction coil. And the dynamic convergence correction device excellent in usability can be provided. (2) Each coil can be arranged so that each side of the horizontal direction correction coil and the vertical direction correction coil formed in the circumferential direction of the holder does not overlap, thereby preventing the coil shape from being disturbed due to thickening of the coil. Thus, it is possible to provide a dynamic convergence correction device in which the accuracy of the coil shape is improved and the variation of the correction magnetic field distribution is small.

According to the fifth aspect of the present invention,
In addition to the effects of any one of claims 1 to 4, when the horizontal correction coil and the vertical correction coil are wound around the outer peripheral surface of the holder and disposed, the horizontal correction coil and the vertical It is possible to prevent a conductive wire forming the correction coil from being caught on the end of the holder, improve the accuracy of the winding, and provide a dynamic convergence correction device excellent in mass productivity.

According to the invention described in claim 6 of the present invention,
The length of the holder of the horizontal direction correction coil and the vertical direction correction coil in the long direction can be reduced, and accordingly, the length of the holder in the long direction can be reduced,
Therefore, it is possible to shorten the neck of the cathode ray tube in which the holder is mounted, and it is possible to provide an image display device that can be made thin.

[Brief description of the drawings]

FIG. 1A is a perspective view of a main part of a dynamic convergence correction device according to a first embodiment. FIG. 1B is a side view of a main part of the dynamic convergence correction device according to the first embodiment.

FIG. 2A is a diagram illustrating magnetic lines of force generated by a horizontal correction coil, and FIG. 2B is a diagram illustrating deflection of an electron beam.
Explanatory diagram showing deflection of electron beam

FIG. 3 is a block diagram of a circuit for driving the dynamic convergence correction device.

FIG. 4 is an explanatory diagram showing a relationship between a holder, a horizontal correction coil, and a vertical correction coil.

FIG. 5A is a relationship diagram showing a state of a change in the correction magnetic field intensity when the magnitude of A1 is changed in the horizontal direction correction coil. FIG. 5B is a view showing how the size of A1 is changed in the vertical direction correction coil. Diagram showing how the corrected magnetic field intensity changes when

6A is a perspective view of a main part of a dynamic convergence correction device according to a second embodiment. FIG. 6B is a side view of a main part of the dynamic convergence correction device according to the second embodiment.

FIG. 7A is an explanatory view showing a coil shape of the dynamic convergence correction device according to the second embodiment as viewed from a cross-sectional direction of the holder. FIG. Figure

8A is a perspective view of a main part of a conventional dynamic convergence correction device, and FIG. 8B is a side view of a main part of a conventional dynamic convergence correction device.

FIG. 9 is a side view of a main part of a cathode ray tube equipped with a conventional dynamic convergence correction device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Dynamic convergence correction apparatus 2 Holder 3 Chamfer part 4 Guide pin 5 Holding plate 6 Lead terminal 7 Horizontal correction coil 8 Vertical correction coil 9 Timing circuit 10 Microcomputer 11 Memory 12 D / A converter 13 Amplification circuit 14 Holder 15 Horizontal direction correction coil 16 Vertical direction correction coil 17 Projecting portion 18 Curved conducting wire portion 19 Conducting wire portion 20 Holder 101 Dynamic convergence correcting device 102 Holder 103 Guide pin 104 Holding plate 105 Lead terminal 106 Coil 107 Cathode ray tube 108 Screen portion 109 Electron gun 110 deflection yoke 111 purity magnet 112 4 pole magnet 113 6 pole magnet 114 static convergence correction device

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Katsunori Nishihata 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. F-term (reference) 5C042 AA07 HH01 HH12 5C060 CE03 CF01 CF03 HA08

Claims (6)

[Claims] An electron beam emitted from an electron gun disposed at an end of a cathode ray tube on a neck side is applied to a phosphor disposed at an end of a cathode ray tube on a cone side to form an image or the like. A dynamic convergence correction device that is mounted around a neck of the cathode ray tube and deflects the electron beam by a magnetic field to perform convergence correction when displaying, a cylindrical holder that is mounted around the neck, and the holder. Four horizontal directions formed by an air-core coil formed by winding a conductive wire in a substantially rectangular shape curved along the side surface shape of the holder, and provided at substantially equal intervals along the outer peripheral surface of the holder A correction coil and an air-core coil formed by winding a conductive wire in a substantially rectangular shape curved along the side surface shape of the holder, and are provided around the outer circumferential surface of the holder at substantially equal intervals. 4 vertical corrections The horizontal direction correction coil, the side of the side of the horizontal direction correction coil curved along the holder as an arc, a fan-shaped centered around the cylinder center line of the cylindrical holder The vertical angle correction coil is formed so that the angle of the central angle is 75 ° to 85 °, and the side curved along the holder among the sides of the vertical direction correction coil is formed as an arc, and the cylindrical shape is formed. A dynamic convergence correction device, wherein the angle of the center angle of the sector centered on the cylinder center line of the holder is 65 ° to 75 °. 2. An electron beam emitted from an electron gun provided at an end of a cathode ray tube on a neck side of a cathode ray tube is irradiated on a phosphor provided at an end of a cathode ray tube on a cone side to form an image or the like. A dynamic convergence correction device that is mounted around a neck of the cathode ray tube and deflects the electron beam by a magnetic field to perform convergence correction when displaying, a cylindrical holder that is mounted around the neck, and the holder. Four horizontal directions formed by an air-core coil formed by winding a conductive wire in a substantially rectangular shape curved along the side surface shape of the holder, and provided at substantially equal intervals along the outer peripheral surface of the holder A correction coil and an air-core coil formed by winding a conductive wire in a substantially rectangular shape curved along the side surface shape of the holder are provided around the outer circumferential surface of the holder at substantially equal intervals. 4 vertical corrections And at least a part of the sides of the horizontal correction coil and the vertical correction coil that are curved along the holder are further outwardly curved and formed to protrude from the outer peripheral surface of the holder. A dynamic convergence correction device. 3. At least a part of the sides of the horizontal correction coil and the vertical correction coil that are curved along the holder is further outwardly curved and formed to protrude from the outer peripheral surface of the holder. The dynamic convergence correction device according to claim 1, wherein: 4. A length of a side of the vertical correction coil, which is provided in a longitudinal direction of the holder, is equal to a length of a side of the horizontal correction coil in a length direction of the holder. The dynamic convergence correction device according to claim 1, wherein the length is longer than a length of the provided side. 5. The holder according to claim 1, wherein at least a part of one end of the holder is formed with a chamfered portion which is chamfered in a slant shape toward an outer side. Dynamic convergence correction device. 6. An image display device comprising the dynamic convergence correction device according to claim 1. Description: