KR900006148B1 - Electron gun devices of color crt - Google Patents

Abstract

The electron gun structure has a fourth electrode (4) and a third electrode (3), on which electron beam passing apertures (3'R,3'G,3'B) are formed, the third electrode having a number of vertical flat planes (3V), the fourth electrode having a number of horizontal flat planes (4V). In the third electrode (3) having a widith of W and a height of H, each of electron beam passing apertures having a diameter of D is bored through the bottom (3M), and surrounded by a bar ring (3N) having a height of h, and the vertical flat plane (3V) has a width of H'(h<H'<H) and a length of W'(D<W'<W).

Description

Carla Winner's Gun Sphere

1 is a cross-sectional structural view of a typical inline electron gun sphere.

2a and 2b are horizontal deflection magnetic field and vertical deflection magnetic field distribution charts.

3 is a beam shape on a fluorescent surface exhibited by a conventional electron gun structure.

4 is a perspective view of a cap electrode structure of a conventional third electrode.

5 is a perspective view of an electrode structure of a conventional fourth electrode.

Figure 6 is a perspective view of the cap electrode structure of the third electrode according to the present invention.

FIG. 7A is a conventional equipotential line distribution diagram when the vertical and horizontal parallel plates are not provided on the third and fourth electrodes. FIG.

(b) is a conventional equipotential line distribution diagram which appears in the in-line direction when the third electrode and the horizontal plate are provided with the fourth electrode and the horizontal plate.

(c) is a potential line distribution diagram of the present invention in which the third electrode has a vertical flat plate in a plane perpendicular to the inline direction.

8A is an overall and equipotential line state diagram for the case where there is no baring portion around a conventional electron beam through hole.

(b) is a state diagram of the electric field and equipotential lines when there is a baring section for the present invention.

* Explanation of symbols for main parts of the drawings

3: third electrode 3M: bottom

3R, 3G, 3B: Electron beam passing hole 3N: Baring part

3V: Resin Flat 4V: Resin Flat

4: fourth electrode

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electron gun for an inline type color cathode ray tube, and in particular, emits a plurality of electron beams from a cathode to connect each electron beam, and concentrates and reproduces each of the plurality of focused electron beams on a point of a color image tube phosphor screen. The present invention relates to an electron gun sphere for a color cathode ray tube in which the main lens forming electrode structure is improved to form an optimal beam spot.

In general, an in-line type electron gun body integrating a common electrode with an electrical structure in a color water pipe, as shown in FIG. 1, includes a first electrode 1 and an electron beam that control a plurality of electron beams. The third electrode 3 including the accelerating second electrode 2 and the bottom electrode 3a and the cap electrode 3b for focusing the electron beam, and the fourth electrode 4 in which the electrostatic shielding cup 7 is welded to the open end side. ) Are sequentially arranged so that the bead glass 5 is fixed while maintaining the above electrodes at small intervals, and the three electron beam through holes 4R, 4G, 4B formed in the fourth electrode 4 have a third electrode. (3) is drilled slightly larger than the 3 electron beam through holes 3R, 3G, and 3B of the cap electrode 3b, and the center electron beam through holes of the cap electrode 3b and the fourth electrode of the third electrode 3 are formed. The 3G and 4G are concentric circles, and the outer electron beam passing holes 3R and 3G and 4R and 4G are configured to be out of center with each other.

The three electron beams emitted from the conventional electron gun sphere cathode 6 are slightly focused by the tip focus lens formed between the second electrode 2 and the third electrode 3 under the control of the first electrode 1. After that, the degree of formation at the third electrode 3 and the fourth electrode 4 is focused by the main electrostatic lens and then reaches the fluorescent surface 8.

In this case, the three electron beams are deflected in the horizontal and vertical directions by a deflection yoke (not shown), and the desired character or graph is displayed on the fluorescent surface 8, but the curvature of the curved surface of the fluorescent surface 8 and the focusing curvature of the electron beam are different. The beam spot formed at the center of the fluorescent surface 8 and the beam spot formed at the periphery are not equally focused. The reason why the curvature of the fluorescent surface 8 and the curvature 10 of the focus are different is that the fluorescent surface 8 needs to be as flat as possible from the observer's point of view, which is the main cause of the difference in the distance from the deflection center 9 to the fluorescent surface 8. .

In the above-described deflection yoke, the horizontal deflection magnetic field is distorted in the pin cushion phase distribution as shown in FIG. 2 (a) and the vertical deflection magnetic field is distorted in the barrel phase distribution as in FIG. 2 (b), and the phosphor of FIG. Large distortion occurs in the shape of the beam spot on the surface of the screen 8, in particular the electron beam incident on the peripheral water 12. Therefore, the beam spot is the power source at the center portion 11 on the surface of the phosphor screen 8, while the core portion 13 is a high elliptical shape having a long elliptical shape with a horizontal deflection at the periphery portion 12, and a low length extending in the vertical direction. The haze 14 which is luminance appears.

This shape is remarkable in the periphery of the screen, which is greatly influenced by the non-uniform magnetic field, and because the focal length difference of the cathode ray tube is larger at the periphery of the screen, it is not possible to obtain a good image quality, so that the cathode ray tube can be used for text or graphics. Problems such as deterioration of the resolution of the color as well as bad color occurred.

In order to solve such a conventional problem, US Patent No. 4,086,513 shows a plurality of vertical partition walls 3V on the cap electrode 3b of the third electrode, and horizontal partition walls 4V on the fourth electrode, as shown in FIGS. 4 and 5. The invention to install is presented. However, in the U.S. patent, the vertical bulkhead 3V of the cap electrode 3b of the third electrode is attached in the direction of the fourth electrode, so that in operation, 26 to 30% of the potential of the fourth electrode (6.5 ~ 7.5 KV) was applied. However, the conventional configuration causes another problem such as discharging easily between the vertical bulkhead and the fourth electrode due to the high electric field, or when the vertical bulkhead (3V) contacts the fourth electrode when assembling the electron gun, resulting in the characteristics of the color cathode ray tube. It has a profound effect.

6 is a perspective view of a cap-type electrode structure to solve such a conventional problem of the present invention.

In the third electrode 3, three electron beam through holes 3'R, 3'G, 3'B are drilled in the bottom portion 3M of the inside of the cap, and each electron beam through hole 3'R, 3 is provided. Barring portion 3N is formed to surround the 'G, 3'B).

Several vertical plates 3V are installed at equal intervals along the electron beam through holes 3'R, 3'G, 3'B arranged around the baring portion 3N.

When the vertical length of the vertical flat plate 3V is W 'and the horizontal length is H', it is designed smaller than the width W and height H of the cap electrode, and the electron beam through holes 3'R, 3'G, 3 It is preferable to set larger than the diameter (H) of the 'B' and the height (h) of the baring portion (3N) formed around the electron beam through holes (3'R, 3'G, 3'B). That is, from the same drawing, the horizontal length H 'of the vertical flat plate 3V has the condition of h <H' <H and the vertical length W 'of the vertical flat plate 3N has the condition of D <W' <W. do.

Referring to the operation and effect of the present invention having such a configuration, if there is no baring portion 3N around each electron beam through hole drilled in the bottom portion of the third electrode cap, the edge effect of the electric field is as shown in FIG. As a result, the potential becomes unstable at the A point of the electrode, which not only swings the path of the electron beam but also increases the halo phenomenon.

Therefore, the baring portion 3N is disposed around the through hole of the G3 electrode, thereby reducing the edge effect of the electrode and stabilizing the electron beam path as shown in FIG. 8 (b), thereby increasing the operation of the vertical plate 3V.

In the cap electrode of the third electrode of FIG. 5, the three beams are crushed in advance by the vertical plate 3V, so as to be horizontally reduced, and the horizontal plate 4V of the fourth electrode 4 of FIG. It passes through the three electrodes 3 but defocuses the electron beams about the vertical axis.

Referring to FIG. 7, a vertical cross-sectional view of a conventional electrostatic lens formed by the cap electrode 3b and the fourth electrode 4 of the third electrode 3 of FIG. 1 without a vertical or horizontal flat plate is illustrated.

Equipotential lines of the electrostatic lens show the effect of the electrostatic lens with two electron paths C and S. The electron path C passes through the center of the lens and S passes out of the center.

The electrostatic lens does not affect the path C of the center electrons but converges the electrons of the path S off the center in the lens center direction. In FIG. 5 in which the horizontal plate 4V is attached to the fourth electrode, the equipotential lines are spread in the direction of the spherical plate 4V as shown in FIG. 7B, whereby the path S of electrons out of the center is defocused. The defocusing action of this electrostatic lens has no effect on the path C of the intermediate electrons but reduces the convergence to the non-central electrons S.

Therefore, since the horizontal flat plate 4V affects the electron beam along the vertical axis, the electrostatic lens that is distorted along the vertical axis provides the electron beam with a vertically thin long plane focusing.

The vertical flat plate 3V positioned around the electron beam through holes 3'R, 3'G, and 3'B of the cap electrode of the third electrode of FIG. 6 is vertically defocused, and the focus is increased horizontally. Be sure to

As shown in FIG. 7B, an equipotential line is formed to increase the convergence of the non-central electron path S by attaching the vertical flat plate 3V to the third electrode. This in turn increases horizontal focusing, resulting in vertical thinner and longer lengths.

As described above, the vertical plate 3V of the third electrode and the horizontal plate of the fourth electrode compensate for the distortion of the electron beam due to the pincushion distribution of the horizontal deflection magnetic field of the deflection yoke and the barrel distribution of the vertical deflection magnetic field.

Therefore, the effect of the above operation is that the vertical deflection plate attached to the cap electrode of the third electrode is directed toward the inside of the cap of the third electrode, so that the discharge phenomenon due to the high pressure between the third electrode and the fourth electrode does not occur and the electrode contacts. It is possible to provide a stable color cathode ray tube which does not occur, and to obtain a good beam spot shape over the entire screen of the phosphor screen, and to obtain an image that is clearly reproduced. It can be used.

Claims (1)

A plurality of vertical plates (3V) are formed on the third electrode 3 around the electron beam through holes 3R, 3G, and 3B formed in the third electrode 4 and the fourth electrode 4 of the electron gun for inline type cathode ray tube. In the fourth electrode 54 and the horizontal flat plate 4V, the electron beam passing holes 3R, 3G, which are drilled in a diameter D at the bottom 3M in the cap of the third electrode 3, respectively. 3B) The baring part 3N is surrounded by h height, and the horizontal length between the electron beam passing holes 3R, 3G, and 3B is h <H '<H, and the length is D / W' <W. An electron gun sphere of a color water pipe, wherein several vertical flat plates (3V) are provided.

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