KR100525884B1 - Electron gun for CRT - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electron gun for cathode ray tube, and more particularly, to an electron gun for cathode ray tube that effectively improves deflection aberration using a magnetic material formed in an electron gun and improves the resolution of a display screen.

An electron gun for a cathode ray tube according to the present invention is an inline type cathode ray tube electron gun having a cathode in which an electron beam is radiated, a plurality of electrodes sequentially arranged in a screen direction from the cathode, and a shield cup, wherein at least one of the shield cup or the plurality of electrodes is provided. It is characterized in that the position of the shortest mutually perpendicular portions of the magnetic bodies provided above and below the path of the outer electron beam is located between the center of the outer electron beam through hole and the center of the center electron beam through hole.

Electron gun for cathode ray tube according to the present invention has the advantage that the haze phenomenon of the red and blue electron beams on the left and right of the screen generated by the self-convergence deflection magnetic field is prevented.

In addition, the cathode ray and electron gun according to the present invention has the advantage that the resolution is improved because the three electron beams are focused at the same intensity throughout the screen.

Description

Electron gun for cathode ray tube {Electron gun for CRT}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electron gun for cathode ray tube, and more particularly, to an electron gun for cathode ray tube that effectively improves deflection aberration using a magnetic material formed in an electron gun and improves the resolution of a display screen.

1 is a view for explaining a conventional cathode ray tube structure.

Referring to FIG. 1, the conventional color cathode ray tube includes a panel 1, which is a front glass, and a funnel 2, which is a rear glass that is coupled to the panel 1, is coupled and sealed, and the inside thereof is maintained in a vacuum state. Vacuum tube.

A fluorescent surface 11 is formed on an inner surface of the panel 1, and an electron gun 8 is installed on a neck portion of the funnel 2 facing the fluorescent surface 11.

Between the fluorescent surface 11 and the electron gun 8, a shadow mask 3 that performs color screening at a predetermined interval with the fluorescent surface 11 is provided at a predetermined interval, and the shadow mask 3 is a mask frame ( 4) and is elastically supported by the spring (5) and supported by the panel (1) with stud pins (6).

The mask frame 4 is combined with an inner shield 7 made of a magnetic material to reduce the movement of the electron beam by an external magnetic field, thereby reducing the influence of the geomagnetic field behind the CRT.

On the other hand, a neck of the funnel 2 is provided with a convergence purity correction magnet (CPM) 10 for adjusting the R, G, B electron beams so that the electron beam emitted from the electron gun 8 converges at one point. A deflection yoke 9 is provided for deflection of the electron beam.

In addition, the reinforcing band 12 is installed to strengthen the front glass according to the vacuum state inside.

Referring to the operation of the color cathode ray tube constructed as described above, the electron beam emitted from the electron gun 8 is deflected in the vertical and horizontal directions by the deflection yoke 9, and the deflected electron beam is the beam passing hole of the shadow mask 3. By hitting the fluorescent surface 11 on the front surface, the desired predetermined color image is displayed.

Here, the convergence purity correction magnet 10 corrects the convergence and purity of the R, G and B electron beams, and the inner shield 7 shields the influence of the geomagnetic field behind the cathode ray tube.

2 is a view for explaining the structure of a conventional electron gun.

Referring to FIG. 2, the conventional electron gun 8 includes an eyelet 13 that fixes the hot cathode, and a hot cathode support assembly 15 connected to the outside of the eyelet 13 and fixed to the bead glass 14. A triode comprising a hot cathode for directly emitting hot electrons by the heating of the heater and a first grid electrode 16 and a second grid electrode 17 for controlling the electron beam; The main lens unit includes third, fourth, fifth and sixth grid electrodes 18, 19, 20, and 21.

A shield cup 22 is formed on the left side of the sixth grid electrode 21 to shield and weaken the leakage magnetic field of the deflection yoke, and the cathode to sixth grid electrode 21 is provided. The silver is arranged at predetermined intervals along the axis of the electron gun 8 and is buried in a pair of bead glass 14 which is a rod-shaped electrical insulator.

Three electron beam through holes 23 are formed in the first grid electrode 16 to the sixth grid electrode 21 in a direction symmetrical to the traveling direction ZZ direction of the electron beam, respectively. It is formed on the same plane of the electrode.

Referring to the operation of the conventional electron gun based on the above-described configuration, the amount of hot electrons emitted by the heating of the heater is controlled by the first grid electrode 16 and accelerated by the second grid electrode 17. .

Then, the focusing electrode passes through the third grid electrode 18, the fourth grid electrode 19, the fifth grid electrode 20, and the sixth grid electrode 21 in order to focus and finally accelerate to hit the entire screen. do.

The three electron beams of R, G, and B coincide at the center of the screen by the static convergence action of the main lens.

At this time, when the three electron beams are deflected to the periphery of the screen by using a uniform magnetic field, the three electron beams fall short of the screen and coincide with each other due to the difference in distance to the screen.

To solve this problem without a separate circuit, a self-convergence magnetic field is used.

The self-converging magnetic field consists of a pin cushion type horizontally and a barrel type magnetic field vertically.

3 is a view for explaining a pincushion type magnetic field.

Three electron beams are deflected from side to side by the pincushion type magnetic field as shown in FIG. 3, forming a self-converging magnetic field together with the barrel-type magnetic field in the vertical direction, and the three electron beams coincide with one point.

However, due to the characteristics of the self-convergence magnetic field, the electron beam undergoes some distortions. Especially, the R, G, and B electron beams are focused on different vertical directions on the left and right sides of the screen. A haze is caused and a blue beam haze is induced on the left side of the screen, resulting in a decrease in resolution in the entire screen.

4 is a diagram illustrating a pincushion magnetic field caused by a deflection yoke in the shield cup of the electron gun and thus the force applied to the electron beam.

Referring to FIG. 4, assuming that the electron beam is emitted from the bottom of the ground, the direction of the magnetic field is directed from the bottom to the top, and thus the three electron beams are forced to the right by Fleming's left hand law.

However, as shown in FIG. 4, the red electron beam receives a focusing force in the vertical direction and the blue electron beam diverges in the vertical direction according to the shape of the pin-cushion type magnetic field. There is a problem that the phenomenon of lack of focus occurs.

An example of an electron gun for solving this problem is disclosed in Japanese Laid-Open Patent Publication No. Hei 10-116570, Korean Laid-Open Patent Publication 2001-0091314, 1997 IDW Society (p473).

Japanese Patent Application Laid-open No. Hei 10-116570 corrects deflection aberration of an electron beam by using a magnetic piece on a part of the electron gun electrode and using a separate magnetic field generating means that operates in synchronization with the deflection.

However, since a separate magnetic field generating means is installed outside the neck and a signal synchronized with deflection is applied, and a magnetic piece is also installed inside the electron gun, there is a problem in that it is difficult to manufacture with an increase in cost. Since the magnetic field generating means is synchronized with the deflection of the deflection yoke and is coupled in a circuit, the deflection yoke of the deflection yoke is lowered, so that excessive power consumption and heat are generated, which makes it difficult to apply.

In addition, a technique for solving this phenomenon by using a separate external applied voltage synchronized with deflection in a separate configuration of the electron gun was introduced to the IDW Society (p473) in 1997. Since at least two additional electrodes having structures opposite to each other are installed and new changing voltages are applied to the existing dynamic voltages, at least one additional voltage of several kV is required. Applying such additional kV voltage to an electron gun is difficult in reality, and there is a problem in that the cost of applying an additional variable voltage increases.

Korean Patent Laid-Open Publication No. 2001-0091314 improves deflection aberration by using a magnetic piece installed in an electron gun and a magnetic field caused by a deflection yoke, but is most easily applied, but a small magnetic piece is disposed between an outer electron beam passing hole and a central electron beam passing hole. According to the arrangement, there is a disadvantage in that the magnetic field is not sufficiently utilized as desired.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and an object thereof is to solve a haze phenomenon of red and blue electron beams on the left and right of a screen caused by a self-convergence deflection magnetic field.

In addition, an object of the present invention is to improve the resolution by converging three electron beams at the same intensity throughout the screen.

Hereinafter, an electron gun for a cathode ray tube according to the present invention will be described in detail with reference to the accompanying drawings.

5A is a view for explaining that a magnetic substance is attached to the shield cup in the electron beam for cathode ray tube according to the present invention.

Referring to FIG. 5A, the shield cup of the cathode ray tube electron gun according to the present invention includes a cathode in which an electron beam is radiated, a plurality of electrodes sequentially arranged in the screen direction from the cathode, and a shield cup. Alternatively, at least one of the plurality of electrodes is positioned between the centers of the outer electron beam through holes and the center of the center electron beam through holes, wherein the positions of the shortest mutually perpendicular portions of the magnetic bodies provided above and below the path of the outer electron beams are positioned.

In more detail, the magnetic bodies 24a, 24b, 24c, and 24d are symmetrical above and below the outer electron beam passing holes 22a and 22c among the three electron beam passing holes 22a, 22b and 22c formed on the shield cup 22 surface. The magnetic bodies 24a, 24b, 24c, and 24d are asymmetrically disposed in the left and right directions with respect to the center of the outer electron beam passing holes 22a and 22c.

At this time, the left and right or the horizontal direction is defined as the direction of the line connecting the center of the three electron beam through-holes (22a, 22b, 22c), the vertical or vertical direction refers to the direction perpendicular to the straight line of the left and right or the horizontal direction.

In particular, magnetic bodies are disposed close to each other in the vertical direction in the vicinity of the center electron beam through-hole 22b with respect to the center of the outer electron beam through-holes 22a, 22b, and 22c. It is disposed relatively far in the vertical direction.

Preferably, the positions of the shortest mutually perpendicular portions of the magnetic bodies 24a, 24b, 24c, and 24d are closer to the center of the outer electron beam through holes 22a and 22c than the center of the center electron beam through hole 22b. Is located.

In addition, the magnetic bodies 24a, 24b, 24c, and 24d may be formed to be inclined at an angle of 18 degrees to 57 degrees with respect to the horizontal axis in a rectangular shape.

It is formed at an angle of 18 degrees to 57 degrees to form a barrel-type magnetic field which is preferable to eliminate the haze phenomenon.

In addition, the magnetic bodies 24a, 24b, 24c, and 24d are rectangular to be inclined at an angle of 20 degrees to 23 degrees with respect to the horizontal axis so that the haze phenomenon is eliminated and the convergence problem is also solved.

In addition, the magnetic body is preferably formed to be longer than the center of the outer electron beam through holes (22a, 22c).

In general, when the electron beam passes the shield cup 22 due to the static convergence action of the main lens, the outer electron beams are moved from the center of the outer electron beam through hole toward the center through hole, more specifically, the center of the outer electron beam through hole is It can be expressed as the center of the outer electron beam when passing through the shield cup 22.

In addition, the distance from the center of the center electron beam through-hole 22b to the center of the outer electron beam through-holes 22a and 22c is l, and the magnetic bodies 24a, 24b, 24c and 24d at the center of the center electron beam through-hole 22b. When the distance to the end point of the center electron beam through hole 2b of the side is l ', it is preferable that l' / l is 0.5 or more and less than 1.

That is, it is preferable that l '/ l satisfies 0.5≤l' / l≤1.0.

If l '/ l is less than 0.5, the effects of the magnetic materials 24a, 24b, 24c, and 24d are small, and the haze phenomenon is not solved. If l' / l is larger than 1.0, the red electron beam focuses in the vertical direction. The blue electron beam is strengthened and the divergence force is enhanced in the vertical direction, rather the haze phenomenon is caused more.

FIG. 5B is a diagram illustrating a change in the magnetic field due to the magnetic body attached to the shield cup. FIG.

Referring to FIG. 5B, a typical magnetic material has a specific magnetic permeability of 1000 or more, and since the nonmagnetic material and the vacuum are 1 to 2 and 1, respectively, most of the magnetic force lines are moved through the magnetic material.

In the present invention, when the relative permeability is 5 or more, the desirable correction effect is obtained.

As shown in FIG. 5B, magnetic force lines that pass up and down the outer electron beam through holes 22a and 22c by the magnetic bodies disposed above and below the outer electron beam through holes 22a and 22c are caused by the magnetic bodies 24a, 24b, 24c and 24d. The magnetic force lines moving along the inside of the trailing magnetic bodies 24a, 24b, 24c, and 24d and leaving the magnetic body are disposed in a path having the smallest magnetic resistance, that is, the path closest to the magnetic body.

Therefore, as shown in FIG. 5B, the inside of the outer electron beam through holes 22a and 22c has almost no pincushion type magnetic field, and is disposed closest to the center electron beam through hole 22b side of the outer electron beam through holes 22a and 22c. Due to the magnetic material generated, a barrel type magnetic force line is generated in the path of the electron beam.

In addition, the magnetic body is formed to be longer than the center of the outer electron beam through holes (22a, 22c) to prevent the pincushion type magnetic field is formed at the end of the magnetic body.

The density of the magnetic force lines at the most adjacent positions of the upper and lower magnetic bodies has a strong magnetic force line because the magnetic bodies are arranged at a constant angle with respect to the magnetic force lines due to the deflection yoke.

Compared to FIG. 4, the red electron beam caused by the pincushioned horizontal deflection magnetic field generates excessive focusing while the blue electron beam causes the lack of focus, but is effectively compensated by the barrel type horizontal deflected magnetic field of FIG. 5B. You can see that.

In this way, the path of the magnetic force lines passing through the outer electron beam through holes 22a and 22c is changed to suppress the distribution of the pincushion type magnetic force lines inside the outer electron beam through holes 22a and 22c, and the outer electron beam passes through the magnetic force lines focused by the magnetic body. Deflection aberration can be corrected by creating a strong barrel-type magnetic field line inside the ball.

It is a figure explaining another Example in the electron gun for cathode ray tubes which concerns on this invention.

Referring to FIG. 6A, the magnetic bodies 25a, 25b, 25c, and 25d are formed in parallel and spaced apart from each other at a predetermined interval on a horizontal axis, between the outer electron beam through holes 22a and 22c and the central electron beam through hole 22b. It is formed by bending at an angle of 90 degrees in the horizontal axis direction.

In addition, the portion formed parallel to the horizontal axis of the magnetic material is formed longer than the center of the outer electron beam through holes (22a, 22c).

As shown in FIG. 6B, a barrel-shaped magnetic field is formed as a protruding portion that is bent at an angle of 90 degrees in the horizontal axis direction of the magnetic body, and a portion formed parallel to the horizontal axis of the magnetic body is formed from the center of the outer electron beam through holes 22a and 22c. By forming the outer side to prevent the pincushion type magnetic field is formed at the end of the magnetic material.

7A is a view for explaining another embodiment of the electron gun for cathode ray tube according to the present invention.

Referring to FIG. 7A, the magnetic bodies 26a, 26b, 26c, and 26d are rectangular and are inclined at an angle of 18 degrees to 57 degrees with respect to the horizontal axis, and the portions of the magnetic bodies installed vertically in the vertical direction are 90 degrees apart. It is bent at an angle and formed to protrude in the direction of the central electron beam through-hole at an angle of 18 degrees to 57 degrees relative to the horizontal axis.

It is formed at an angle of 18 degrees to 57 degrees to form a barrel-type magnetic field which is preferable to eliminate the haze phenomenon.

In addition, the magnetic bodies 26a, 26b, 26c, and 26d are formed to be inclined at an angle of 20 degrees to 23 degrees with respect to the horizontal axis so as to eliminate the haze phenomenon and to solve the convergence problem.

In addition, it is preferable to form the magnetic body outwardly longer than the center of the outer electron beam through holes 22a and 22c.

As shown in FIG. 7B, a barrel-type magnetic field is formed at a portion that is the shortest distance from each other in the vertical direction of the magnetic bodies installed above and below, and a portion formed longer outside the center of the outer electron beam through holes 22a and 22c is the outer electron beam through hole 22a. , 22c) to prevent a pincushion type magnetic field from being formed.

Therefore, when the screen is deflected on the right side, it is possible to prevent the focusing phenomenon of the red electron beam and the lack of focusing of the blue electron beam, and when the screen is deflected on the left side of the screen, the focusing phenomenon of the red electron beam is prevented and the focusing phenomenon of the blue electron beam is prevented. do.

Electron gun for cathode ray tube according to the present invention has the advantage that the haze phenomenon of the red and blue electron beams on the left and right of the screen generated by the self-convergence deflection magnetic field is prevented.

In addition, the cathode ray and electron gun according to the present invention has the advantage that the resolution is improved because the three electron beams are focused at the same intensity throughout the screen.

1 is a view for explaining a conventional cathode ray tube structure.

2 is a view for explaining the structure of a conventional electron gun.

3 is a diagram for explaining a pincushion type magnetic field.

4 is a diagram illustrating a pincushion magnetic field caused by a deflection yoke in a shield cup of an electron gun and thus a force applied to an electron beam.

5A is a view illustrating a magnetic body attached to a shield cup in an electron gun for a cathode ray tube according to the present invention;

5B is a view for explaining the change of the magnetic field due to the magnetic body attached to the shield cup.

6A is a diagram for explaining another embodiment of the electron gun for cathode ray tubes according to the present invention;

6B is a view for explaining the change in the magnetic field of another embodiment in the electron gun for cathode ray tubes according to the present invention;

7A is a view for explaining another embodiment of an electron gun for a cathode ray tube according to the present invention;

Fig. 7B is a view for explaining the change in the magnetic field of another embodiment in the electron beam gun for cathode ray tubes according to the present invention.

<Explanation of symbols for main parts of drawing>

One ; Panel 2; Funnel

3; Shadow mask 4; Mask frame

5; Spring 6; Stud pins

7; Inner shield 8; Electron gun

9; Deflection yoke 10; Magnet for convergence purity correction

11; Fluorescent surface 12; Reinforcement band

13; Eyelet 14; Bead glass

15; Hot cathode support assembly 16; First grid electrode

17; Second grid electrode 18; Third grid electrode

19; Fourth grid electrode 20; Fifth grid electrode

21; Sixth grid electrode 22; Shield cup

22a, 22b, 22c; Electron beam through hole

24a, 24b, 24c, 24d; Magnetic material

25a, 25b, 25c, 25d; Magnetic material

26a, 26b, 26c, 26d; Magnetic material

Claims (12)

An inline type cathode ray tube electron gun having a cathode in which an electron beam is radiated, a plurality of electrodes sequentially arranged in a screen direction from the cathode, and a shield cup, At least one of the shield cup or the plurality of electrodes is located between the centers of the outer electron beam through holes and the center of the center electron beam through holes, wherein the positions of the shortest mutually perpendicular portions of the magnetic bodies provided above and below the path of the outer electron beams are positioned. The magnetic body has a rectangular shape is parallel to the horizontal axis spaced apart at a predetermined interval, the electron gun for the cathode ray tube, characterized in that bent and projected at an angle of 90 degrees in the horizontal axis direction between the outer electron beam through hole and the central electron beam through hole. The method of claim 1, Electron gun for the cathode ray tube, characterized in that each magnetic material provided above and below the path of the outer electron beam is asymmetrical with respect to the center of the outer electron beam through hole. The method of claim 1, The electron gun for cathode ray tube, characterized in that the position of the shortest distance between the magnetic material in the vertical direction is located closer to the center of the outer electron beam through hole than the center of the center electron beam through hole. The method of claim 1, Electron gun for cathode ray tube, characterized in that the magnetic permeability of the magnetic material is 5 or more. delete delete delete delete delete The method of claim 1, The magnetic gun is a cathode ray tube electron gun, characterized in that formed longer than the center of the outer electron beam through hole. An inline type cathode ray tube electron gun having a cathode in which an electron beam is radiated, a plurality of electrodes sequentially arranged in a screen direction from the cathode, and a shield cup, At least one of the shield cups or the plurality of electrodes is positioned between the centers of the outer electron beam through holes and the center of the center electron beam through holes, and the positions of the shortest mutually perpendicular portions of the magnetic bodies provided above and below the path of the outer electron beam are mutually located. The position of the longest part in the vertical direction is formed outside the path of the outer electron beam, The magnetic material is a cathode ray tube electron gun, characterized in that extending in the vertically bent at the shortest distance in the vertical direction. delete