KR910002973B1 - Electron gun for color cathode ray tube - Google Patents

Abstract

In electron gun for colour cathode ray tube having lens of maximum aperture, the three beams are focussed by a principal lens comprising a focussing electrode to which at least two low potential are applied and set opposite it, and an accelerating electrode to which a high potential is applied. In this time, beam pass through (11) is arranged by eqvivalent space in linear on beam pass plate (14) of the above electrodes. The pass plate (14) is cutted with H- type to form main electrode part (12). This apparatus has good static convergence and emables easy.

Description

Electron gun for color cathode ray tube

1 is a plan sectional view of a conventional inline electron gun.

FIG. 2 is a sectional view taken along the line II-II of the electron gun shown in FIG. 1, showing the front of the focusing electrode well.

3 shows a conventional focusing electrode formed differently from FIG. 2, in which FIG. 3a is a front view thereof, and FIG. 3b is a planar cross-sectional view thereof.

4 is a perspective view of a focusing electrode of an embodiment in which an electron gun according to the present invention is shown.

FIG. 5 is a front view showing a state before the upper and lower main electrode pieces are not bent and the auxiliary electrode is coupled thereto in the manufacturing process of the electrode shown in FIG.

6 is a perspective view of an auxiliary electrode coupled to the electrode illustrated in FIG. 4.

7 is a front view of the electrode shown in FIG.

FIG. 8 is a side cross-sectional view of the electrode shown in FIG.

9 is a front view illustrating a manufacturing process of an electrode according to another exemplary embodiment of the present invention and corresponds to FIG. 5.

FIG. 10 is an exploded perspective view of an auxiliary electrode coupled to the electrode shown in FIG. 9.

FIG. 11 is a relative front view of an electrode according to another embodiment of the present invention, the components of which are shown in FIGS. 9 and 10.

12 is a cross-sectional plan view of an assembled state of an electrode according to another exemplary embodiment of the present invention, in which parts thereof are shown in FIGS. 9 and 10.

* Explanation of symbols for main parts of the drawings

10: electrode 11: circular hole

12: main electrode piece 13: protruding piece

14: electron beam transmission plane of the electrode 15, 22: cutout

21, 21 ': electrode piece of the auxiliary electrode 23: cutout

24: beam penetration hole 26: final sign

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of an electron gun for color cathode ray tube, and more particularly to an electron gun for color cathode ray tube having a lens of maximum aperture for an electrode of a limited size.

The spherical aberration of the electron beam by the electron lens of the color cathode ray tube electron gun influences the focusing characteristics of the electron beam, which affects the resolution of the cathode ray tube much.The spherical aberration of the electron beam, like the optical lens, has a large aperture and The smaller the magnification, the better. Various improvements have been made for this purpose, but there are constraints on forming a larger lens, if possible, on a limited size electrode.

As an example, three circular beam through holes 2 are formed on the electrodes of the inline electron gun, as shown in FIG. 2, and these cylindrical beam through holes 2 are equally spaced from each other. Keep it. Here, the distance S between the centers of the beam through holes should be at least about 1 mm longer than the diameter D of each beam through hole due to technical limitations in the die processing of the electrode. In addition, the distance a between the inner wall of the neck 3 and the electrode 1 should be maximized as much as possible in consideration of the withstand voltage of the anode, while the center distance S of the beam passing hole is effectively concentrated by three electron beams. It should be minimized as much as possible for convergence. That is, the size of the electrode 1 is limited to a certain value or less by the inner diameter of the neck of a limited size, and the beam through hole drilled to the electrode 1 of the limited size should be as large as possible, but the distance between the centers thereof should be close to each other. The size of the beam passing hole is adjusted by the condition of being. However, the beam through hole formed in the electrode of the shape as shown in FIG. 2 is substantially sized by the size of the inner diameter of the neck due to the condition that the spacing of each beam through space must be 1 mm or more as described above. It is decided to go.

One means for overcoming this limitation is disclosed in Korean Patent Publication No. 82-1555, as shown in FIG. 3 of the drawings attached to this specification. That is, in order to extend the diameter of the beam passing holes (2) forming the lens to be larger than the center interval of each beam passing hole (2), the individual beam passing holes in the superimposed state are formed, each beam passing hole (2 Auxiliary electrode 5 is additionally provided between (2) and (2) to exclude interference between electron beams passing through each center. However, this type has a problem that the focus characteristics of the electron beam passing through each beam through hole are not identical because the shape of the center beam through hole and the beam through holes on both outer sides thereof are not the same.

Therefore, the present invention was devised to overcome the problems of the prior art as described above, and the present invention improves the spherical aberration of the electron beam by the main lens and also maintains the focus characteristics of the three electron beams uniformly. An electron gun for a color cathode ray tube which can improve the image quality in the present invention is provided.

In order to achieve the above object, the present invention is to form a beam through holes through which three electron beams pass on the plane and the electron beam passing plane of the main lens forming focusing electrode and the acceleration electrode of the electron gun for inline color cathode ray tube at equal intervals in a straight line The upper and lower sections of the electron beam passing plane are cut up and down in an H-shape to form a main electrode piece divided up and down about a straight line passing through the centers of the beam passing holes, and the main electrode piece cut up and down is formed on the electrode. It is characterized in that the auxiliary electrode is bent at a predetermined angle to the inner space of the second electrode, and an auxiliary electrode for excluding interference between electron beams passing between the main electrode pieces is provided between each beam passage and outside of both outer beam passage holes.

Hereinafter, preferred embodiments of the present invention illustrated in the accompanying drawings will be described in detail.

4 is a perspective view of a preferred embodiment of the present invention, Figure 5 is a front view of the state in the manufacturing process of the electrode shown in Figure 4, three beam through holes (11) , (11) and (11) are formed at equal intervals on the beam passing plane 14 and the beam passing plane 14 passes through the centers of the beam passing holes 11, 11 and 11, respectively. The upper and lower main electrode pieces 12 and 12 are formed by cutting along the straight line h, and the upper and lower main electrode pieces 12 and 12 are divided by a proper angle into the inner space of the electrode 10. At this time, the bending angle should be adjusted according to the design conditions of the electron gun, and accordingly, about 45 ° is preferable as shown, in consideration of processability and assemblability.

As described above, four rectangular auxiliary electrodes are provided to provide independence of the three beam passing holes 11, 11, and 11, which are communicated with each other by bending the main electrode pieces 12, 12. Pieces (21), (21), and (21) are fitted between the beam passing holes and outside the left and right beam passing holes. To this end, as shown in FIG. 6, the straight cutouts 22 and 22 formed to be inclined toward the center are formed at the corners of the auxiliary electrode pieces 21, respectively, so that the upper and lower main electrode pieces 12 and 12 are formed. Corresponding protrusion pieces 13, 13 formed in the above are fitted. In this case, the angles of the notches 22 and 22 with respect to the edges of the auxiliary electrode pieces are the same as those of the bend angles of the main electrode pieces 12 and 12.

In addition, the adjacent pair of auxiliary electrode pieces 21 and 21 are preferably connected by the joining piece 26 so as to maintain a predetermined interval.

One embodiment of the present invention configured as described above includes a main electrode piece 12 formed up and down on the electron beam passing plane 14 of the electrode 10, as shown in the front view of FIG. 7 and the side cross-sectional view of FIG. The bending of (12) causes the beam passing holes (11), (11), and (11) to be expanded and deformed into a long hole shape close to a rectangle that extends above and below the electrode 10 of a limited size. If the distance between the centers of the through holes is 6.6 mm, the horizontal length of the deformed beam through holes may be up to 5.6 mm, whereas the vertical length may be extended up to 9 mm. In this way, the beam through hole of the same shape can be obtained in which the beam through hole has been elongated from a circle to a square. Therefore, the spherical aberration of the electron beam is improved through the large-diameter beam passing hole, and since the three electron beam passing holes have the same shape in spite of being maximized as compared with the related art, the focus characteristic of the electron beam passing through them This can appear virtually the same.

In addition, an auxiliary electrode piece 21 for providing independence between the beam passing holes 11, 11, and 11 is disposed between the beam passing holes 11, 11, and 11. In addition, by being mounted outside the beam passing holes on both sides, the modified beam passing holes are separately distinguished, thereby preventing the interference between the electron beams, in particular the repulsive force between the beams, thereby preventing the degradation of the beam characteristics due to the interference.

As described above, according to the present invention, the aperture of the electrostatic lens is increased due to the enlargement of the electron beam path, and as a result, the spherical aberration of the electron beam is significantly reduced, and the shape of each of the three modified beam through holes is the same. The difference in focus characteristics between the electron beams passing through the ball becomes very small.

On the other hand, since the beam through hole 11 deformed as described above is longer and longer, it is expanded as a result of the cross section of the electron beam. This feature improves the overall image quality by improving the spot shape at the periphery of the cathode ray tube, which allows the landing of the electron beam in the form of near normal (ie, less hollow) to the screen edge of the cathode ray tube. It is because.

Meanwhile, another embodiment according to the present invention is shown in FIGS. 9 to 12, and the concentration characteristic of the electron beam is improved compared to the above-described embodiment.

This is a cutout portion 15 having a predetermined width and length at the outside of the beam passing holes 11, 11, 11 and the projection pieces 13, 13, 13, and 13 therebetween, (5), (15), and (15) are formed, and the auxiliary electrode pieces 21 and 21 ', which are fitted thereto, are spaced at a certain distance by the intermediate connecting piece 26 as shown in FIG. The pairs are formed in pairs, and in the center of the connecting piece 26, a separate beam through hole 24 coaxial with the beam through holes 11, 11, and 11 is formed. One side of the auxiliary electrode pieces 21, 21 'is formed short, while arc-shaped cutouts 23, 23 are formed in the center of each tip portion thereof. The pair of auxiliary electrode pieces 21 and 21 ′ configured as described above are arranged on the fixing piece 30 having three beam passing holes 31 having the same size as the beam passing holes 24 as shown in FIG. 10. It is preferably attached to the main electrode piece 12 by attaching. The shorter electrode piece 21 'is provided inside the auxiliary electrode pieces 21, 21'.

Herein, when the auxiliary electrode pieces 21 and 21 'are coupled to the main electrode piece 12 and viewed through the eleventh view of the electrode and the cross section 12 of the planar cross section, the electron beam passes through. The shape of the modified beam passing holes 11, 11, and 11 is the same as that of the first embodiment shown in FIG. 7, while the auxiliary electrode pieces 21, 21 'are described above. When fitted to the cutouts 15 and 15 of the electrode pieces 12 and 12, the arc shaped cutouts 23 and 23 of the tip portions of the auxiliary electrode pieces 21 and 21 'are moved forward. Exposed. In addition, it is necessary to make the long auxiliary electrode piece 21 of the auxiliary electrode pieces outwardly positioned and the short electrode piece 2l 'located inside.

The second embodiment of the present invention configured as described above has the features of the first embodiment described above and at the same time has other advantages as follows.

That is, as shown in FIG. 12, the lengths of the two auxiliary electrode pieces 21 'and 21' in the middle are shorter than the lengths of the outer auxiliary electrode pieces 21 and 21 on both sides thereof, and the tip of each electrode piece is short. Since the arc-shaped cutout part 23 is provided in the center, the electrostatic area | region by high pressure is strongly shifted outward. Therefore, it is easy to concentrate the three electron beams passing therethrough, and thus there is no need to eccentrically move the electron beam.

Claims (8)

The color cathode ray in which beam passing holes 11, 11, and 11 are arranged at equal intervals on each beam passing plane l4 of the focusing electrode and the acceleration electrode constituting the main lens through which three electron beams pass. In the conventional electron gun, the main electrode pieces 12, 12 divided up and down about the straight line h passing through the centers of the beam passing holes 11, 11, and 11 are formed. An electron gun for a color cathode ray tube, characterized in that the electron beam passing plane (14) is cut in an up-and-down H shape, and the main electrode pieces (12) and (12) are bent at an angle to the inner space of the electrode (10). The beams of claim 1, wherein the three beam passing holes 11, 11, and 11 are enlarged and deformed by the main electrode pieces 12 and 12 that are separated and bent vertically. An electron gun for a color cathode ray tube, characterized in that an auxiliary electrode piece (21) is provided between the through holes (11), (11), and (11). The method according to claim 1, wherein independence of the three beam passing holes (11), (11), and (11) expanded and deformed by the main electrode pieces (12) and (12) divided up and down, and the respective shapes thereof. An electron gun for a color cathode ray tube, characterized in that an auxiliary electrode piece (21) is provided between each deformed beam through hole (11) and outside of both beam through holes (11). The auxiliary electrode piece 21 according to claim 2, wherein the auxiliary electrode piece 21 is formed of quadrangular pieces, and two corners adjacent to each other are formed with cutouts 22 directed toward the center thereof to protrude in the main electrode piece 21. An electron gun for a color cathode ray tube, characterized in that the piece 13 is fitted. The electron gun for a color cathode ray tube according to claim 4, wherein the two auxiliary electrode pieces (21) adjacent to each other are connected together by a connecting piece (26) so as to maintain a predetermined distance from each other. According to claim 2 or 3, wherein the auxiliary electrode piece 21 is formed in a pair connected by a predetermined distance by the intermediate connecting piece 26, the beam through hole 24 in the center of the connecting piece (26) ), Wherein the beam passing hole (24) and the expanded beam passing hole (11) are coaxially positioned when coupled to the main electrode piece (12). 7. The electron gun for color cathode ray tube according to claim 6, wherein the auxiliary electrode pieces coupled to the main electrode pieces are formed to be shorter than those provided on the outside of the two modified beam through holes. The auxiliary electrode piece (21) according to claim 2 or 3, wherein the auxiliary electrode piece (21) is composed of four pieces, and the center portion of the edge of the tip is cut off to insert the protruding piece (13) of the main electrode piece (21). Electron gun for color cathode ray tube, characterized in that.

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