KR20010094887A - Beam index type cathode ray tube - Google Patents

Abstract

PURPOSE: A cathode ray tube is provided, in which reinforcing member with high magnetic permeability is arranged inside of electrode of electron gun, to thereby effectively correct rotation of electron beam landing at the edge of the screen. CONSTITUTION: A cathode ray tube comprises a tube having a vacuum interior; a screen unit having a fluorescent stripe, black matrix, aluminum film and index stripe, and which is arranged inside of the tube; an electron gun arranged in the tube to opposed to the screen portion; a deflection unit arranged at the tube, and which deflects the electron beam scanned from the electron gun to the screen portion; a focusing unit arranged at the tube, and which senses the light emitted from the index stripe; a correction unit arranged at the tube where the electron gun is arranged, and which corrects rotation of electron beam; and a reinforcing unit(42) arranged at the position corresponding to the correction unit, and which reinforces rotation correction for electron beam. The correction unit is constituted by four solenoids(30,32,34,36), wherein solenoids(30,34) arranged in a vertical direction(V) form N-pole and solenoids(32,36) arranged in a horizontal direction(H) form S-pole.

Description

Cathode ray tube of beam index method {BEAM INDEX TYPE CATHODE RAY TUBE}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cathode ray tube of a beam index type, and more particularly to a beam index type cathode ray provided with a magnetic quadrupole to correct a landing state of an electron beam scanned into a peripheral portion of a screen portion. It's about the coffin.

The cathode ray tube of the beam index method is a cathode ray tube designed to compensate for the problems of the ordinary cathode ray tube. The cathode ray tube drives the electron gun unit by synchronizing the index signal sensed by the electron beam with a color signal provided from the outside of the cathode ray tube. The electron beam generated by the electron gun has a mechanism capable of realizing a predetermined image by always landing on the phosphor at a desired position.

As an advantage of the beam index type cathode ray tube, it is possible to prevent miss landing of the electron beam due to the shadowing of the shadow mask because it does not employ the shadow mask, which is a color sorting means, and to implement a color image with one electron gun. It is possible to prevent misconvergence due to misalignment of R, G and B electron beams.

On the other hand, in the beam index type cathode ray tube, it is important to adjust the size of the electron beam to an optimal state so that the electron beam does not strike the phosphor of one color when it strikes the phosphor of one color.

However, in the cathode ray tube, due to the geometrical structure of the windshield of the cathode ray tube, the electron beam 1 landing at the corner portion of the screen is, as shown in FIG. 6, the electron beam landing at another portion of the screen portion 2. Compared to (3), it is not properly arranged in a vertical state-a state formed long in the vertical direction y of the screen part-and is inclined and landed in a state rotated at a predetermined angle φ with respect to the vertical direction y. It is a known fact. The landing state of the electron beam appears more as the size of the cathode ray tube becomes larger and the windshield becomes flat.

Such a phenomenon has a bad effect on controlling the size of the electron beam (the size of the horizontal direction (x) of the screen) in the cathode ray tube of the beam index method, conventionally, efforts have been made in various ways to compensate for this.

In the related art related art, when the electron beam is finally landed on the screen, the electron beam is subjected to the magnetic field formed from the magnetic quadrupole, which is any magnetic field generating device, before passing through the magnetic field generated in the deflection device. There is one that can be landed.

That is, as shown in Fig. 7, conventionally, a magnetic field generating device consisting of solenoids 7, 9, 11 and 13 is provided on the neck portion 5 of the cathode ray tube, and is generated by the electron gun portion to be a corner portion of the screen portion. Before the scanned electron beam 15 enters the deflecting device, the shape of the screen is deformed under the influence of the magnetic field generated by the solenoids 7, 9, 11 and 13 (indicated by the dotted lines in the drawing). When landing at the corners, it is possible to make a good landing in a vertical state. Conventionally, these solenoids 7, 9, 11 and 13 were formed by winding a coil around a ferrite core which is mainly a paramagnetic body.

For reference, in the case of a beam index type cathode ray tube having a diameter of 29.1 mm, the core is formed of pure iron having good transmittance, and the coil is wound about 200 times to form the above magnetic quadrupole.

However, in the cathode index tube of the beam index method using the magnetic quadrupole, the amount of current consumed through the magnetic quadrupole is not small, resulting in a large power consumption. Substantially, in the beam index type cathode ray tube of the above example, it is known that the rotationality of the electron beam can be corrected to some extent only by using a high current of about 10 A for each solenoid constituting the magnetic quadrupole.

In addition, the magnetic quadrupole should be mounted so that the centers of the solenoids arranged in all directions of the electron beam are exactly centered with respect to the electron beam according to their structural relationship. For example, if the solenoid arrangement is not centered and shows a small amount of error, it does not accurately perform rotational correction for the electron beam that lands at the corner of the screen, but rather forms an unnecessary magnetic field. When scanning negatively, by hitting a phosphor other than the desired phosphor, there is a problem that the image quality of the screen is eventually reduced.

Accordingly, the present invention has been made in view of the above problems, and an object of the present invention is to provide a beam index type cathode ray tube for correcting the rotatable landing of an electron beam using a magnetic quadrupole made of a solenoid. Even if an error occurs somewhat in the mounting state of the quadrupole, a beam index type cathode ray is provided so that the magnetic field distribution on the electron beam is not abnormal.

In addition, another object of the present invention is to provide a cathode ray tube of the index type to reduce the power consumption by lowering the current value required to correct the rotation correction of the electron beam.

1 is a side cross-sectional view showing a cathode ray tube of the beam index method according to an embodiment of the present invention,

2 is a cross-sectional view illustrating an important part of a beam index type cathode ray tube according to an embodiment of the present invention;

3 to 5 is a perspective view showing a reinforcing member according to an embodiment of the present invention,

FIG. 6 is a view illustrating a state of an electron beam landing on each screen portion of a conventional beam index cathode ray tube.

7 is a cross-sectional view showing a state where a conventional magnetic quadrupole is mounted on a beam index cathode ray tube.

Accordingly, the present invention to realize the above object,

A tube in which the inside is kept in a vacuum state;

A screen unit including a phosphor stripe, a black matrix, an aluminum film, and an index stripe formed on one side of the inner surface of the tube;

An electron gun section provided on the tube so as to face the screen section;

A deflection portion installed in the tube to deflect an electron beam scanned from the electron gun portion to the screen portion;

A light collecting part installed on the tube to sense light emitted from the index stripe;

Correction means installed at the tube portion in which the electron gun unit is installed to correct rotation of the electron beam; And

Reinforcing means arranged at least in a position corresponding to the correcting means to enhance rotation correction of the electron beam;

It provides a cathode ray tube of the beam index method comprising a.

In such a cathode ray tube, the correction means is preferably formed by opposing the magnetic poles having the same polarity in the vertical and horizontal directions of the screen portion, and the reinforcing means is pure iron and ferrite permalloy of high permeability material. It is preferably provided on the electrode electron beam through-hole forming surface of the electron gun portion.

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

1 is a side cross-sectional view showing a cathode ray tube of the beam index method according to an embodiment of the present invention.

As shown in the drawing, the cathode ray tube is shaped as a tube 20 which maintains an internal atmosphere in a vacuum state, and the tube 20 is largely formed of a panel 20a and a panel 20a forming a front glass. It includes a funnel 20b connected to the rear and a neck 20c extending to the rear of the funnel 20b.

In the tube 20, a screen portion 22 including R, G and B phosphors is formed on the inner surface of the panel 20a. In addition to the R, G and B phosphors, the screen portion 22 is formed. A black matrix formed between these R, G and B phosphors, an aluminum metal bag formed on the R, G and B phosphors and the black matrix, and an index phosphor formed on the aluminum metal bag are further included.

In addition, the inside of the neck 20c includes a cathode 24a and a plurality of (first to fourth) grease electrodes 24b, 24c, 24d, and 24e to scan a single electron beam into the screen unit 22. The electron gun 24 is provided, and a deflecting portion 26 for deflecting the electron beam and a light collecting portion for detecting light emitted from the index phosphor of the screen portion 22 on the outer circumference of the funnel 20b. 28 is installed.

In addition, an electron beam formed in the electron gun portion 24 is deflected by the deflection portion 26 on a portion of the tube 20 where the electron gun portion 24 is installed, that is, on the outer circumference of the neck 20c. When scanned into the corner portion of the section 22, the electron beam is in a vertical state (when the final spot shape of the electron beam landing on the screen section is formed long in the vertical direction of the screen section, the electron beam is clockwise or counterclockwise. As a means for preventing the landing from being rotated in a state in which it is not rotated and in a state where it is landed in the vertical direction without being rotated, the following correction means is provided.

That is, the correcting means is formed so as to face the magnetic poles having the same polarity in the vertical or horizontal direction of the screen portion to achieve the above-described action under the influence of the magnetic field formed by the magnetic poles, The configuration is as shown in FIG.

As can be seen from the figure, the correction means is made of a quadrupole pole, wherein the pole is made of solenoids (30, 32, 34, 36). That is, the solenoids 30 and 34 arranged in the vertical direction V of the screen part 22 are formed to form magnetic poles of the N pole, and the solenoids arranged in the horizontal direction H of the screen part 22. 32 and 36 are made to form the magnetism of the S pole. The plurality of solenoids 30, 32, 34, and 36 are electrically connected to the spot slope correction circuitry 40 of the electron beam to receive current therefrom.

For reference, the current supplied from the correction circuit unit 40 changes in response to the deflection operation of the electron beam. For example, when the electron beam is deflected to the upper left of the screen portion 2 of FIG. 6, the solenoids 30, 32, 34, and 36 will form a magnetic field so that the electron beam can be forced in the direction of the arrow in FIG. Will be supplied.

On the other hand, in the present invention, when correcting the rotation landing of the electron beam by the action of the quadrupole as described above, the solenoids (30, 32, 34, 36) are not disposed exactly opposite to the tube axis of the cathode ray tube to affect the electron beam In case the magnetic field formation cannot be formed satisfactorily, the following reinforcing means are provided.

The reinforcing means is disposed at least one or more positions at positions corresponding to the solenoids 30, 32, 34, and 36 to enhance rotation correction of the electron beam. At the third grid electrode 24d. In more detail, the reinforcing means is provided with a high permeability material (eg, pure iron, ferrite, permalloy, etc.), that is, the center of the electrode of the electron gun 24, that is, the electron beam passing hole 240d through which the electron beam passes. Consists of a reinforcing member 42 for concentrating the magnetic flux to the center of the, it is installed on the surface (242d) formed with the electron beam through hole (240d) of the third grid electrode (24d).

The reinforcing member 42 made through the present embodiment is selected from any one of the above materials, as shown in FIG. 3, and is made of a thin plate, and has one side end, that is, the electron beam passing hole 240d for enhancing its function. One side end facing toward can be formed sharply.

In this embodiment, as shown in FIG. 2, the reinforcing member 42 is provided in all four directions of the third grid electrode 24d around the electron beam through hole 240d.

The beam index cathode ray tube having such a reinforcing member 42, upon its operation, scans an electron beam from the electron gun section 24 to the screen section 22 according to a color signal synchronized with the index signal to produce a predetermined image. In an implementation, the magnetic field formed by the four solenoids 30, 32, 34, and 36 before the electron beam passes through the deflection portion 26 for the electron beam scanned into the corner portion of the screen portion 22. Will receive the power of

Then, the electron beam may be well landing in a vertical state with respect to the screen portion 22, that is, in consideration of a state in which it is not rotated and landed, and receives a force of the magnetic field at a predetermined angle with respect to the vertical state. Will rotate.

The direction of force (see arrow) by the magnetic field applied to the electron beam in FIG. 2 is for the electron beam landing to the upper left of the screen portion 22 as described above, which electron beam passes through the magnetic field region. When it is rotated at a predetermined angle by the force, and is deflected into the corner portion of the screen portion 22 by the magnetic field of the deflection portion 26, it lands properly in a vertical state.

In this operation, the reinforcing member 42 serves to collect magnetic force lines formed at the solenoids 30, 32, 34, and 36 toward the electron beam. That is, as shown in FIG. 2, the reinforcing member 42 induces the magnetic force lines formed in the solenoids 30, 32, 34, and 36 to the electron beam so that a high magnetic flux density is caused to rotate the electron beam. Enhance the degree of sex landing correction.

In this embodiment, the magnetic field is applied to the electron beam by applying the reinforcing member 42 to a 29-inch beam index cathode ray tube having a diameter of 29.1 mm in the neck 20c. As a result of the test of the strength of the coil, it can be seen that the conventional coil has the same effect as the number of windings of the coils constituting the solenoids 30, 32, 34 and 36 and the amount of current supplied thereto. have.

For example, when the solenoids 30, 32, 34, 36 are conventionally configured, when the number of windings of the coil wound around the core of the solenoid is 200 times and the amount of current supplied thereto is 20 A, the rotational force of the electron beam Although the correction can be achieved with a predetermined result, in the present invention, the number of turns of the coil is 50 times (in this case, the core is made of ferrite), and the rotational correction of the electron beam can be achieved to the same degree as before even when the current amount is 1A. Could.

Further, even if the number of windings of the coil and the amount of current flowing through the coil were reduced according to the material of the reinforcing member 42, the strength of the magnetic field applied to the electron beam could be made the same as before. In the case of (42) made of pure iron, the number of windings and the current amount of the coil is 1/50 of the conventional value, and when the reinforcing member 42 is made of ferrite or permalloy, it is 1/65 to 1/70 of the conventional value. Could be lowered.

As described above, in the present invention, the reinforcing member 42 compensates for the rotational landing of the electron beam in the quadrupole method consisting of the solenoids 30, 32, 34, and 36. It becomes possible.

4 and 5 is a perspective view showing a reinforcing member according to another embodiment of the present invention, the reinforcing member 44 shown in Figure 4 has the same overall shape as the reinforcing member 42 of the above-described example, the inside In the longitudinal direction, a plurality of recesses 44a are formed. That is, the reinforcing member 44 is a heat generated by the eddy current or the skin effect in the process of inducing the above-mentioned magnetic force line during the above-described action, the heat generated through the recessed portion (44a) It was configured to reduce the degree.

In addition, the reinforcing member 46 shown in FIG. 5 has a recessed portion 46a similarly to the reinforcing member 44 of the above-described example, as well as the width of the reinforcing member 46 at one end thereof. A cover portion 46b having a width Wl larger than Ws is formed. When the reinforcing member 46 induces a magnetic force line from the solenoids 30, 32, 34, and 36, the magnetic force line can be induced in a wider range through the cover portion 46b, thereby improving efficiency. It can be increased even more.

On the other hand, in the above example, it can be seen that the shape of the reinforcing member installed in all directions of the third grid electrode has the same shape as in FIG. 2, but this is not necessarily the case. For the optimization of the material, the material, shape, and other sizes may be made separately.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications and changes can be made within the scope of the claims and the detailed description of the invention and the accompanying drawings. Naturally, it belongs to the range of.

Thus, the beam index type cathode ray tube according to the present invention, due to the reinforcement member made of a high permeability material installed in the electrode of the electron gun portion, the rotational correction of the electron beam landing on the corner of the screen in a quadrupole manner more than before. It can be achieved effectively.

Further, the present invention, even if the magnetic pole of the quadrupole is not located exactly in the top, bottom, left and right centered on the electron beam, the magnetic force lines formed from the solenoid of the quadrupole through the reinforcing member effectively extends to the electron beam, a problem that has conventionally occurred (The increase in the size of the electron beam due to the unbalanced magnetic field, the separate provision of the centering deflection device to correct this, etc.) can be eliminated.

Claims (10)

A tube in which the inside is kept in a vacuum state; A screen unit including a phosphor stripe, a black matrix, an aluminum film, and an index stripe formed on one side of the inner surface of the tube; An electron gun section provided on the tube so as to face the screen section; A deflection portion installed in the tube to deflect an electron beam scanned from the electron gun portion to the screen portion; A light collecting part installed on the tube to sense light emitted from the index stripe; Correction means installed at the tube portion in which the electron gun unit is installed to correct rotation of the electron beam; And Reinforcing means arranged at least in a position corresponding to the correcting means to enhance rotation correction of the electron beam; Cathode ray tube of the beam index method comprising a. The method of claim 1, And a beam index type cathode ray tube, wherein the correction means is arranged so that magnetic poles having the same polarity in the vertical and vertical directions of the screen portion face each other. The method of claim 2, The cathode ray tube of the beam index method wherein the magnetic pole is made of a solenoid. The method of claim 1, The cathode ray tube of the beam index method, wherein the reinforcing means is installed on the electrode of the electron gun section. The method of claim 4, wherein The cathode ray tube of the beam index method, wherein the reinforcing means is provided on the electron beam through hole forming surface of the electrode. The method according to claim 1 or 4 or 5, The reinforcement means is provided with a high permeability material beam index type cathode ray tube made of a reinforcing member for concentrating the magnetic flux to the electrode center of the electron gun. The method of claim 6, One side end portion of the reinforcing member sharply formed cathode ray tube of the beam index method. The method of claim 6, Beam reinforcing cathode ray tube of the reinforcing member is made of any one of pure iron, ferrite or permalloy. The method of claim 6, The cathode ray tube of the beam index type formed with a plurality of recesses for reducing heat generation in the reinforcing member. The method of claim 6, When the width in the unidirectional direction of the reinforcing member is Ws, a beam index type cathode ray tube having a cover portion having a width (Wl) greater than the width (Ws) on one side end of the reinforcing member.