KR100322076B1 - Electron gun for CPT - Google Patents

Abstract

Disclosed is an electron gun for a color cathode ray tube. The disclosed electron gun for a cathode ray tube includes a cathode, a control electrode, and a screen electrode forming a triode; In the electron gun for a color cathode ray tube comprising a plurality of focus electrodes and a final acceleration electrode constituting the auxiliary lens and the main lens, a single large diameter through which three electron beams pass through the focus electrode facing the screen electrode to form a prefocus lens; An outer rim electrode member having an electron beam through hole formed therein; And an inner electrode member installed inside the outer rim electrode member and having three independent small diameter electron beam passing holes formed therein.

Description

Electron gun for color cathode ray tube {Electron gun for CPT}

The present invention relates to an electron gun for a color cathode ray tube, and more particularly, to an electron gun for a color cathode ray tube having an improved structure of an electrode constituting an electron lens.

1 shows an example of an electron gun provided with an electrode forming an electron lens.

Referring to the drawings, the electron gun for the color cathode ray tube; Three cathodes (KR) (KB) (KG) constituting the triode 10, a control electrode G1 and a screen electrode G2 each having three electron beam through holes formed therein, and an auxiliary to focus and accelerate the electron beam. A focus electrode G3 forming a lens and a final acceleration electrode G5 disposed adjacent to the focus electrode G3 to form a main lens are included.

As a predetermined potential is applied to the electrode configured as described above, a prefocus lens is formed between the screen electrode G2 and the focus electrode G3, and a main lens is disposed between the focus electrode G3 and the final acceleration electrode G5. Is formed.

Therefore, the electron beam emitted from the cathode KR (KB) KG is prefocused and accelerated by the prefocus lens and the auxiliary lens, and then enters the main lens. The prefocus lens is an diverging lens portion and adjusts the aperture width and the depth of the electron beam incident on the main lens as its depth.

Since the electron beam through hole formed on the incident side of the screen electrode G2 and the focus electrode G3 forming the prefocus lens is a relatively small independent small diameter electron beam through hole, when the voltage is increased to strengthen the prefocus lens, the prefocus is increased. Since the magnification of the lens is increased to increase the spherical aberration, the angle of incidence is increased. Therefore, the electron beam passing therethrough is deteriorated, thereby deteriorating the focus characteristic.

The present invention has been made to solve the problems described above, and an object thereof is to provide an electron gun for color cathode ray tubes that can improve the resolution of an image.

1 is a cross-sectional view of a conventional electron gun,

2 is a cross-sectional view of an electron gun according to a preferred embodiment of the present invention.

3 is a perspective view of a common large diameter electrode that is a feature of the invention.

<Explanation of symbols for main parts of drawing>

G1 ... control electrode G2 ... screen electrode

G3, G30, G40 ... Focus electrodes

G5, G50 ... Fast acceleration electrode G30-1 ... Inner electrode member

G30-2 ... Outer electrode member

In order to achieve the above object, the electron gun for a color cathode ray tube of the present invention includes a cathode, a control electrode, and a screen electrode forming a triode; In the electron gun for a color cathode ray tube comprising a plurality of focus electrodes and a final acceleration electrode constituting the auxiliary lens and the main lens, a single large diameter through which three electron beams pass through the focus electrode facing the screen electrode to form a prefocus lens; An outer rim electrode member having an electron beam through hole formed therein; And an inner electrode member installed inside the outer rim electrode member and having three independent small diameter electron beam passing holes formed therein.

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

2 and 3 illustrate a preferred embodiment of the electron gun for the color cathode ray tube according to the present invention.

Referring to the drawings, an electron gun for a color cathode ray tube according to the present invention comprises three cathodes KR (KG) KB arranged in an inline form, forming a triode 10, a control electrode G1, and a screen electrode. (G2).

In addition, in the electron gun for color cathode ray tube according to the present invention, a first focus electrode G30 having a single large-diameter electron beam passing hole for forming at least one electron lens for focusing and accelerating an electron beam is provided next to the screen electrode G2. The second focus electrode G40 is installed after the first focus electrode G30.

The final acceleration electrode G50, which is adjacent to the second focus electrode G40 far from each cathode KR (KG) KB, forms a main lens.

The first focusing electrode G30 is formed as two cups, and the outer rim electrode member G30-2 having a single large-diameter electron beam passing hole formed therein is combined therein as a characteristic of the color cathode ray electron gun of the present invention. It consists of a common large diameter first focus electrode G30 provided with the internal electrode member G30-1.

The internal electrode member G30-1 is a flat member, and has R, G, and B electron beam passing holes R, G, and B of independence small diameters formed inline. The first focus electrode G30 focuses and accelerates the electron beam emitted from the cathode KR KG.

In order to apply the common large-diameter first focus electrode G30 described above, in the basic HI-BI potential focus and UNI-BI focus electron guns, the first focus electrode G30 which is a prefocus lens unit is used. A common large diameter is applied to the cup-shaped outer rim electrode member G30-2 to adjust the angle of the electron beam incident to the main lens as the opening width and depth of the large diameter electrode, thereby improving relative focus performance.

In the case of the high-by-focus method, the focus deterioration according to the single focus method can achieve an effect closer to the main lens part than the length of the focus electrode part, and in the case of the uni-bi focus method, the design of the length of the focus electrode part is limited. This exists, but forms a common large diameter to improve the focus characteristic which is a problem of the uni-by gun.

Referring to the operation of the electron gun for the color cathode ray tube according to the present invention configured as described above are as follows.

The electron gun for the color cathode ray tube according to the present invention is prefocused between the screen electrode G2 and the outer rim electrode member G30-2 of the common large-diameter first focus electrode G30 in a state where it is mounted on the funnel neck portion of the cathode ray tube. The lens is formed.

Here, the internal electrode member G30-1 installed inside the outer rim electrode member G30-2 constituting one side of the common large diameter first focus electrode G30 as a feature of the present invention has a focus characteristic by a common large diameter. Further, the prefocus lens formed between the screen electrode G2 and the common large-diameter first focus electrode G30 adjusts the aperture width and the angle of the electron beam incident on the main lens as its depth as the diverging lens portion.

When a predetermined potential is applied to the common large-diameter first focus electrode G30 and the final acceleration electrode G50, which are the focus electrodes of the electron gun, a predetermined potential is applied between the common large-diameter second focus electrode G40 and the final acceleration electrode G50. The main lens is formed.

When the electron beam is emitted from the cathode KR (KB) (KB) of the tripolar portion 10 in the electron gun of the present invention in which the lens group is formed, the emitted electron beam is focused and accelerated while passing through the above-described electron lenses. After being deflected by the deflection yoke (not shown), it is landed on the fluorescent point of the fluorescent film to excite the fluorescent film.

As described above, the electron gun for the color cathode ray tube of the present invention has the effect of improving the focus performance by forming the focus electrode as a common large-diameter focus electrode.

The present invention has been described with reference to one embodiment shown in the accompanying drawings, which is illustrative, and those skilled in the art will understand that various modifications and equivalent embodiments are possible. . Therefore, the true scope of protection of the present invention should be defined only by the appended claims.

Claims (1)

A cathode, a control electrode, and a screen electrode forming a triode; In the electron gun for a color cathode ray tube comprising a plurality of focus electrodes and the final acceleration electrode constituting the auxiliary lens and the main lens, An outer rim electrode member having a single large-diameter electron beam passing hole through which three electron beams pass through the focus electrode facing the screen electrode to form a prefocus lens; And an inner electrode member provided inside the outer rim electrode member and having three independent small-diameter electron beam passing holes formed therein.