KR20010001060A - electron gun for color cathode ray tube - Google Patents

Abstract

PURPOSE: An electronic gun for color cathode ray tube is provided to maintain the width wider than length ratio of electronic beam passing through the second electrode in the optimum condition without sinking a width wider than length slot in the second electrode. CONSTITUTION: An electronic gun for color cathode ray tube comprises the plurality of negative pole, three pole portion, a free focus lens and two electrodes or more. The three pole portion consists of the second electrode(11-1). The second electrode(11) is divided with two. The first electrode(11-1) of the second electrode(11) faces to the first electrode(10), forms a lens together with the first electrode(10) and the negative pole and accelerates the electron beam. Also, the electron beam through hole(11-1a) is formed in the first electrode(11-1) and the electron beam through hole(11-2a) is formed in the second electrode(11-2). The second electrode(11-2) of the second electrode(11) faces to the third electrode(12) and is wider than length. The electron beam by the electron beam through hole(11-2a) of the width wider than length, when concentrating and accelerating the electron beam.

Description

Electron gun for color cathode ray tube

The present invention relates to an electron gun used in a color cathode ray tube or a high-definition industrial monitor, and more particularly, to a second electrode of an electron gun, which serves to pull out and accelerate hot electrons generated from an electron emission material of a cathode. It is about.

1 is a side view showing a part of a general color cathode ray tube, in which a cathode ray tube includes a panel 1, a phosphor layer 2 coated with red, green and blue phosphors on an inner surface of the panel, and a cone shape. The neck portion 3a is integrally formed with the funnel 3 fixed to the panel, the shadow mask 5 which is installed in close proximity to the inner surface of the panel and serves as the color selection of the electron beam 4, and the funnel of the An electron gun 6 enclosed in the neck portion 3a to scan the electron beam 4 to the screen side, and a deflection yoke 7 mounted on the outer circumferential surface of the neck portion to deflect the electron beam emitted from the electron gun in a vertical or horizontal direction, or the like. Consists of.

Each electrode of the electron gun 6 applied to the cathode ray tube is arranged in-line perpendicular to the path through which the electron beam passes so that the electron beam generated from the cathode can be controlled at a constant intensity to reach the screen.

The configuration of the electron gun is described in more detail with reference to FIG. 2 as follows.

FIG. 2 is a schematic view of the electron gun applied to FIG. 1, wherein three heaters 9 each having a heater 8 embedded therein and arranged in parallel with each other horizontally, and arranged at a constant distance from the cathode are generated at the cathode. The first electrode 10 for controlling the hot electrons, and arranged to maintain a predetermined distance from the first electrode to draw and accelerate the hot electrons gathered on the surface of the electron emitting material (not shown) of the cathode (9) The second electrode 11, the third electrode 12, the fourth electrode 13, and the fifth electrode 14 and the sixth electrode 15 forming a main lens for mainly focusing and accelerating the electron beam. It is composed of a pair of bead glass (not shown) to maintain a constant interval.

Different voltages are applied to the cathodes 9 so as to obtain a constant current value so that the cut-off voltages are necessarily the same.

Therefore, the electron gun 6 having the above-described structure generates electrons from the cathode 9 when the heater 8 embedded in the cathode 9 receives power from the stem pin 17 and generates heat. The electron beam 4 to be controlled is controlled by the first electrode 10 and accelerated by the second electrode 11 which is an acceleration electrode.

Thereafter, the electron beam is slightly focused by a prefocus lens formed by the third electrode 12, the fourth electrode 13, and the fifth electrode 14, and then the fifth electrode 14, which is the main lens forming electrode, and While passing through the sixth electrode 15 and focused and accelerated through the shadow mask 5 provided in proximity to the phosphor layer 2, the screen is reproduced because color is collided to collide with the phosphor layer to emit light.

As described above, when the electron beam 4 emitted from the electron gun 6 leaves the electron gun and proceeds to the screen side, the deflection yoke 7 installed in the neck portion 3a deflects the electron beam in the vertical and horizontal directions over the entire area of the screen. Let it be.

FIG. 2 is an exploded perspective view of a part of the electron gun applied to FIG. 1, and FIG. 3 is a perspective view illustrating a second electrode of USP 4,641,058. The third electrode (3) is formed in the electron beam through hole 11a formed in the second electrode 11. On the surface opposite to 12), as shown in Fig. 3, a groove-shaped depression (hereinafter, referred to as a "row slot") 18 having a smaller direction perpendicular to the inline direction is formed.

The horizontal slot 18 serves to asymmetrically form a lens formed by a potential difference between the second electrode 13 and the third electrode 14.

The voltage applied to the second electrode 13 is 400 to 1,000 V, and the voltage applied to the third electrode 14 is 6,000 to 10,000 V.

FIG. 4 is a perspective view showing a part of a large-diameter main lens for reducing spherical aberration of the main lens of the electron gun. Referring to the configuration, the fifth electrode 14 and the sixth electrode 15 which face each other are disposed. Openings 19 and 20 through which three electron beams pass in common are formed on opposite surfaces, respectively, and are formed inside the fifth electrode 14 and the sixth electrode 15, that is, from the openings 19 and 20. Electrostatic field control electrode bodies 21 and 22 having rectangular electron beam through holes 21a and 22a through which the central electron beam passes are fixed at the retreat points at regular intervals, so that the fifth electrode 14 and the sixth electrode ( 15) the asymmetric main lens having a stronger focusing force of the lens than the direction in which the inline direction is perpendicular thereto while expanding the size of the main lens formed therebetween, causes the electron beam leaving the electron gun 6 to be deflected by the deflection yoke 7 When deflected, they are degraded by the deflection defocusing that occurs. It reduces symptoms.

Therefore, when the electron beam 4 is emitted from the cathode 9 in the electron gun 6 having the structure as described above, it is horizontal by the horizontal slot 18 formed on the opposing surface of the third electrode 13 of the second electrode 11. The lens intensity in the direction is smaller than the lens intensity in the vertical direction so that the electron beam is changed into a horizontal shape in which the horizontal direction is larger than the vertical direction and is incident on the main lens.

In more detail, the three-pole lens is weakened in the horizontal direction by the horizontal slot 18 of the second electrode 11 so as to focus the electron beam small while in the vertical direction the lens intensity is reduced. It is strong and focuses largely, which makes the electron beam horizontal.

The reason for the horizontal lengthening of the electron beam is to reduce the spherical aberration of the main lens formed between the fifth electrode 14 and the sixth electrode 15 with respect to the vertical direction, and employ the deflection defocusing phenomenon and the self-convergence deflection yoke. When the electron beam is deflected by the non-uniform deflection magnetic field, the horizontal direction decreases the focusing force and the vertical direction strengthens the focusing force to compensate for the phenomenon of deterioration of the electron beam.

Hereinafter, the compensation of the deflection defocusing phenomenon will be described in detail.

When the horizontal electron beam is focused on the screen through the main lens, the horizontal focusing distance is formed longer than the vertical direction, and the horizontal focusing distance becomes shorter than the vertical direction, so the electron beam is deflected by the deflection yoke (7). In this case, the deflection defocusing caused by the nonuniform deflection field is compensated.

The asymmetric tripolar portion of the second electrode 11 formed by the lateral slot 18 formed in the direction of the third electrode 12 forms an electron beam generated in the periphery of the screen by forming the water point size of the electron beam in a vertical shape having a horizontal length smaller than the vertical. To compensate for the increase.

Therefore, when these spots are deflected to the periphery of the screen, the amount to be lateralized is reduced to form a circular shape, and the moiré is improved by focus improvement due to reduction of the horizontal spot diameter at the periphery and vertical spot expansion at the periphery of the screen. This reduces the risk of occurrence, which in turn improves the resolution.

However, as the deflection angle increases due to the increase in size of the screen in recent years, the deterioration of the spot is increasing at the periphery of the screen, and in order to improve the depth, the depth d of the horizontal slot 18 formed in the second electrode 11 may be improved. Although it has to be further increased, due to the limitation of the raw material thickness of the second electrode 11, many constraints have been involved in increasing the depth of the ragged slot 18, and also the depth d of the ragged slot 18 by the press d ), There is a problem that it is difficult to compensate for the spot deterioration of the periphery of the screen because a high response technology is required.

FIG. 5 is a graph showing the lateralization ratio of the electron beam according to the depth of depression of the second electrode, and the thickness of the raw material even when the depth d of the lateral slot 18 formed in the second electrode 11 is set to the maximum. Because of this limitation, it can be seen that the lateralization ratio of the electron beam does not reach the lateralization ratio required of the cathode ray tube for 32 "wide TV.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem in the related art, and it is possible to maintain an optimum lateralization ratio of an electron beam passing through the second electrode without recessing the lateral slot in the second electrode. There is this.

According to an aspect of the present invention for achieving the above object, a three-pole portion consisting of a plurality of cathodes for emitting an electron beam, at least two electrodes for controlling the amount of electron beam radiation from the cathode and then accelerated to the screen, and the electron beam An electron gun composed of at least two prefocus lenses for focusing a predetermined amount and two or more electrodes for forming a main lens for focusing the electron beam on the screen, wherein the second electrodes constituting the triode are two Split to form a circular electron beam through hole in the first electrode, the second electrode is formed to form a horizontal electron beam through hole having a greater horizontal than the vertical to install the two electrodes to maintain a constant distance, each electrode 400 An electron gun for color cathode ray tubes is provided, wherein a voltage of ˜1,000 V is applied.

1 is a cross-sectional view of a typical colored cathode ray tube

2 is an exploded perspective view showing a part of the electron gun applied to FIG.

3 is a perspective view showing a conventional second electrode

Figure 4 is a perspective view showing a part of the large-diameter main lens cut out

FIG. 5 is a graph showing the transverse ratio of an electron beam according to the depth of depression of the second electrode

Figure 6 is a perspective view showing a part of the second electrode of the present invention cut away

7 is a graph showing the horizontal ratio of the electron beam according to the present invention;

Explanation of symbols for main parts of the drawings

9: cathode 11-1: first second electrode

11-2: second second electrode 11-1a, 11-2a: electron beam through hole

Hereinafter, the present invention will be described in more detail with reference to FIGS. 6 and 7 as an embodiment.

FIG. 6 is a perspective view showing a part of the second electrode of the present invention, and FIG. 7 is a graph showing the ratio of lateralization of the electron beam according to the present invention. In the present invention, the second electrode 11 is divided into two to form a first electrode. A circular electron beam through-hole 11-1a is formed in the first second electrode 11-1, which is in the shape of a plate located in the direction of the electrode 10, and the second plate, which is spaced apart from the first second electrode by a predetermined distance. In the second electrode 11-2, a horizontal electron beam passing hole 11-2a having a horizontal direction larger than the vertical direction is formed.

A tripolar lens is applied to the two electrodes by applying a voltage of 400 to 1,000 V, which is the same as that of the conventional second electrode 11, by a voltage difference of 6,000 to 10,000 V applied to the third electrode 12 and a potential difference. To form.

In the second electrode having the structure, the first second electrode 11-1 is disposed to face the first electrode 10 to form a lens with the first electrode 10, the cathode 9, and emit an electron beam to the cathode 9. ) And to accelerate.

When the second second electrode 11-2 faces the third electrode 12 and focuses and accelerates the electron beam partially, the second second electrode 11-2 plays a role of horizontalizing the electron beam by the horizontal electron beam passing holes 11-2a. Done.

Since the interval between the first second electrode 11-1 and the second second electrode 11-2 serves as the depth of the depression of the second electrode of the prior art, the lateralization ratio of the electron beam is easily increased. You can do it.

FIG. 7 is a graph showing the change in electron beam horizontal ratio according to the change in the distance g between the first second electrode 11-1 and the second second electrode 11-2 of the present invention. FIG. The design can satisfactorily satisfy the electron beam lateralization ratio of 2.8, which is compatible with the above.

In addition, since the present invention does not have to form a recess around the electron beam through hole 11a formed in the second electrode 11 as in the prior art, it is easy to manufacture a part by press working, and also maintains the accuracy of the dimension well. It has advantages

Therefore, when the electron beam emitted from the electron gun forms an image on the screen, it is possible to form an elongated electron beam having a smaller horizontal water point size than the vertical, thereby compensating for the lateralization of the electron beam generated at the periphery of the screen.

In addition, when the electron beam is deflected toward the periphery of the screen, the amount of the electron beam to be lateralized is reduced to have a shape similar to a circular shape, so that the focus is improved due to the reduction of the horizontal spot diameter at the periphery of the screen, It will reduce the occurrence of moiré.

As described above, the present invention increases the lateralization of the electron beam passing through the second electrode by dividing the second electrode into two, so that even if the deflection angle is increased due to the enlargement of the cathode ray tube, the present invention can sufficiently cope with this. As a result, a uniform focus characteristic can be obtained in all areas of the screen.

In addition, the change of the electron beam transverse ratio at the triode of the electron gun 6 generated by the deflection angle of the cathode ray tube and the change in the size of the screen is the first second electrode 11-1 and the second electrode without new development. Since the distance between the second second electrodes 11-2 can be changed, a design that satisfies the change in the lateralization ratio is possible.

In addition, since the two divided electrodes are punched to form circular and horizontal electron beam through holes 11-1a and 11-2a, the effect of maintaining the accuracy of the dimension is also obtained.

Claims (1)

A three-pole portion comprising a plurality of cathodes for emitting an electron beam, at least two electrodes for controlling the amount of electron beam radiation from the cathode and then accelerating to a screen, and at least two or more prefocuses for focusing the electron beam in a predetermined amount In the electron gun consisting of a lens and two or more electrodes forming a main lens for focusing the electron beam on the screen, the second electrode constituting the triode is divided into two to form a circular electron beam through hole in the first electrode In addition, the second electrode is formed so that the horizontal electron beam through-hole larger than the vertical is formed so that the two electrodes to maintain a constant interval, each electrode is a color characterized in that a voltage of 400 ~ 1,000 V is applied Electron gun for cathode ray tube.