KR100205429B1 - An electron gun for a color crt - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electron gun for a color cathode ray tube, and is capable of suppressing fork deterioration at the periphery of the screen and electron beam horizontalization at the periphery of the screen due to the use of a self-convergence deflection yoke.

The present invention divides and electrically connects one of the electrodes constituting the bi-type lens to at least two or more electrodes, and the second grid-side electrode, which is one of the divided electrodes, is applied with a constant voltage among the electrodes constituting the bi-lens. It is electrically connected to the electrode, and the remaining electrode is an electron gun for a color cathode ray tube electrically connected to the electrode to which the variable voltage of the deflection yoke is applied among the electrodes constituting the bi-lens.

Description

Electron gun for colored cathode ray tube

BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to an electron gun for a color cathode ray tube, and more particularly, focus deterioration at the periphery of a screen and electron beam desorption at the periphery of a screen caused by the use of a self-convergence deflection yoke. The electron gun for a color cathode ray tube which can suppress the phenomenon).

In general, the color cathode ray tube is largely divided into a panel (Pannel) (1) coated with a phosphor (4), funnel-shaped funnel (2), a neck (2a) into which an electron gun is inserted, as shown in FIG. It consists of an electron gun and deflection yoke (3) installed at the neck.

FIG. 2 is a cross-sectional view illustrating a Uni-Bi electron gun which is a kind of an in-line electron gun used in the color cathode ray tube as described above. The cathode 10 includes a plurality of grid electrodes spaced apart from the cathode by a predetermined distance to form a beam forming region, and a plurality of acceleration electrodes disposed away from the grid electrode by a predetermined distance.

Therefore, when the cathode 11 receives power from the stem pin 6 of FIG. 1 and generates heat, hot electrons are emitted from the cathode, and the emitted electron beam is the first grid electrode (called the first control electrode) 11. And a control light accelerated appropriately while passing through a beam forming region composed of a second grid electrode (referred to as a first acceleration electrode) 12 and a third grid electrode (referred to as a first focusing electrode) 13. 13 and a uni-potential formed by a voltage difference applied to the fourth grid electrode (referred to as the second control electrode) 14 and the fifth grid electrode (referred to as the second focusing electrode) 15. The bi-potential is focused and accelerated by an electro-static lens and formed by a voltage difference applied to the fifth grid electrode 15 and the sixth grid electrode (referred to as the second acceleration electrode) 16. Bi-Potential) Focused and accelerated again by the electrostatic lens.

In addition, the path of the electron beam passing through the electrostatic lens, which is the main lens of the electron gun, is determined by the influence of the magnetic field formed by the strength of the current applied to the deflection yoke 3 outside the funnel 2, and proceeds along this condensation. The electron beam 7 passes through a shadow mask 5 provided in front of the fluorescent surface, and emits light while rounding the fluorescent surface.

In order to ensure that the three electron beams 7 implementing blue, green, and red coincide at the center of the screen, the holes through which the outer beam (electron beams implementing blue and red) pass through the electrodes constituting the electrostatic lens are offset. Or in other suitable ways, the electrostatic lens is formed so that the path of the outer beam is directed towards the center pan (green electron beam). Self Convergence deflection yoke is used to form the pin-cushion in the deflection yoke horizontal direction and barrel magnetic field in the vertical direction. 3 electron beams are matched at the front of the screen.

At this time, each of the red, green, and blue electron beams receives a force diverging in the horizontal direction and a focusing force in the vertical direction by the magnetic field of the deflection yoke as described above. Halo phenomenon occurs with over concentration.

Therefore, the research for removing the halo phenomenon in the vertical direction of the electron beam has been in progress for a long time, Figure 3 is a cross-sectional view showing an example of an electron gun for the removal of the halo phenomenon.

The electron gun shown in FIG. 3 uses the second focusing electrode as an electrode to which a static voltage is applied (hereinafter, referred to as a "static electrode" (hereinafter referred to as a "static electrode")) and an electrode to which a dynamic voltage is applied (hereinafter, referred to as an electron gun). And the shape of the openings of the static electrode 15a and the dynamic electrode 15b is a race track shape common to the three electron beams.

The plate electrode 17 is formed with a through hole of each of the three electron beams 7 by retreating at a predetermined interval from the opening of the race track, and the plate electrode 17 has a straight line perpendicular to two inline directions toward the dynamic electrode. The vertical partition wall electrode 18 with a partition is provided, and this vertical partition electrode 18 is welded and fixed to the periphery of an outer electron beam through-hole.

In the dynamic electrode 15b, a horizontal partition wall electrode 19 in which a partition wall parallel to an electron beam passage hole formation surface in the inline direction is common to three electron beams is welded and fixed to the dynamic electrode 15b. A part of 19 is inserted into the racetrack opening of the static electrode 15a.

According to the electrode configuration shown in FIG. 3, when a voltage that is tuned to the deflection yoke 3 and applied to the dynamic electrode 15b is applied to the dynamic electrode 15b, a quadruple lens may be formed due to a difference from a constant voltage applied to the static electrode 15a. Is formed between the static electrode and the dynamic electrode, and the electron beam immediately before being incident on the main lens becomes an elongated electron beam whose horizontal direction is smaller than the vertical direction.

The elongated electron beam of the electron gun compensates for the phenomenon that the vertical direction of the electron beam is over-focused by the deflection field when the deflection yoke is deflected to the corner of the screen, that is, the shortening of the focal length, and thus the vertical direction over the entire screen. It is possible to sufficiently eliminate the halo phenomenon.

However, the electron gun of the above structure does not compensate for the increase of the electron beam in the horizontal direction at the periphery of the screen generated by the self-convergence yoke 3, and the vertical length of the smaller electron beam becomes smaller due to the elimination of the vertical halo. Moire phenomenon can be seen in.

In addition, a device for reducing the horizontal size and increasing the vertical size of the just focused electron beam at the periphery of the screen is disclosed in Japanese Patent Laid-Open No. H6-162956.

The BPF electron gun of the above-described electron gun is divided into three focus electrodes of the electron gun and asymmetrical faces of two electrodes on the anode (anode) side to remove the vertical halo phenomenon of the peripheral electron beam. As the electron beam deflects toward the periphery with the two electrodes on the cathode side being asymmetrical, the diverging angle of the electron beam emitted from the cathode is larger in the horizontal direction and smaller in the vertical direction, resulting in an electron gun having the structure shown in FIG. This solved the problem.

However, when the electron gun having such a structure is also applied to a Hi-BPF electron gun having excellent characteristics than the BFP electron gun, there is a problem that a considerable precision is required.

That is, the length of the fogger electrode is proportional to the focus voltage / anode voltage and the divergence angle of the electron beam emitted from the cathode is inversely proportional to the fogger voltage / anode voltage. When the divergence angle of the electron beam is adjusted at the position of the asymmetric structure electrode, if the dimensions of the asymmetric structure are not assembled correctly, the screen resolution deteriorates due to the focus electrode, which is longer than the BF electron gun.

An object of the present invention is to improve the deterioration at the periphery of the screen caused by the self-convergence deflection yoke and the chemical structure of the CRT and to reduce the moiré phenomena. It is to provide an electron gun.

According to an embodiment of the present invention for achieving the above object, one of the electrodes constituting the bi-type lens is divided into at least two or more electrodes and electrically connected, and the second grid side electrode, which is one of the divided electrodes, Among the electrodes constituting the lens, the electrode is electrically connected to the electrode to which a constant voltage is applied, and the remaining electrode is provided by an electron gun for a color cathode ray tube which is electrically connected to the electrode to which the variable voltage of the deflection yoke is applied. do.

1 is a block diagram of a general color cathode ray tube.

2 is a short side view of a conventional in-line uni-by electron gun that has been used in color cathode ray tubes.

3 is a cross-sectional view of an electron gun to which a dynamic voltage is applied as another example of an inline electron gun.

4 is a cross-sectional view of the inline electron gun according to the present invention.

5a to 5c are detailed views of the third grid electrode applied to the present invention.

5A is a front view of the 3-1 grid electrode.

FIG. 5B is a front view of the third-2 grid electrode viewed from the cathode side. FIG.

Fig. 5C is a front view of the 3-2 grid electrode viewed from the screen side.

* Explanation of symbols for main parts of the drawings

10 cathode 11 first grid electrode

12 second grid electrode 13a 3-1 grid electrode

13b: 3-2 grid electrode 20, 21, 22: hole

4 is a cross-sectional view showing an embodiment in which the present invention is applied to an electron gun of a uni-by structure.

The electron gun has a cathode 10 for emitting electrons, a first grid electrode 11 and a second grid electrode 12 for controlling the electron beam emitted from the cathode, and an electron beam passing through the second grid electrode. The third grid electrode 13, the fourth grid electrode 14, and the fifth grid electrode 15, which are electrodes forming a uni-type lens for properly focusing and accelerating to focus on an old screen, and a bi-type lens The fifth grid electrode 15 and the sixth grid electrode 16, which constitute the electrodes, are sequentially arranged in the tube axis direction.

The third grid electrode 13 is divided into two and composed of the 3-1 grid electrode 13a and the 3-2 grid electrode 13b to maintain a constant distance, and the 3-1 grid electrode 13a. The pore 20 of is formed axially symmetrical.

In addition, in the 3-1 grid electrode side plate electrode pore 21 of the 3-2 grid electrode 13b which is formed by welding the plate-shaped electrode and the cap-shaped electrode, the length in the vertical direction is longer than the length in the horizontal direction. The cap electrode pore 22 on the fourth grid electrode side is formed axis-symmetrically.

The fifth grid electrode is composed of a static electrode 15a and a dynamic electrode 15b, and vertical barrier electrodes 18 and horizontal barrier electrodes 19 are welded and fixed to the static electrodes and the dynamic electrodes, respectively. The voltage of the electrode 15b is variable in synchronization with the deflection yoke 3.

The 3-1 grid electrode 13a is connected to the static electrode 15a of the fifth grid electrode so that the focusing voltage is applied, and the 3-2 grid electrode 13b adjacent to the fourth grid electrode has a deflection yoke ( It is connected to the dynamic electrode 15b of the 5th grid electrode so that it may change in synchronization with 3).

In the electron gun of the present invention as described above, the electron beam changes in the electron gun as follows as the voltage applied to the 3-2 grid electrode 13b and the dynamic electrode 15b increases in synchronization with the deflection yoke.

first. As the voltage applied to the 3-2 grid electrode 13b increases, the electron beam is diverged in the horizontal direction by an asymmetric structure between the 3-1 grid electrode 13a and the 3-2 grid electrode 13b. In the vertical direction, a quadrupole lens for focusing is formed.

second. As the voltage applied to the 3-2 grid electrode 13b increases, the intensity of the uni-lens formed on the 3-2 grid electrode 13b, the fourth grid electrode 14 and the static electrode 15a increases. do.

third. As the voltage applied to the dynamic electrode 15b increases, a quadrupole lens is formed which focuses the electron beam in the horizontal direction and diverges in the vertical direction due to the asymmetrical structure between the static electrode 15a and the dynamic electrode 15b. do.

fourth. As the voltage applied to the dynamic electrode 15b increases, the strength of the bilens formed between the dynamic electrode 15b and the sixth grid electrode 16 becomes weak.

The third feature of the above-described features serves to accurately disperse the vertical direction of the electron beam over-converged by the self-convergence yoke in the electron gun in advance as the electron beam moves to the periphery of the screen.

When the self-convergence yoke is used, the horizontal direction of the electron beam forms an almost accurate image in the entire area of the screen, so the fourth feature weakens the main lens so that the horizontal direction of the electron beam focused by the third feature forms an accurate image on the screen. do.

Therefore, according to the third and fourth features, the electronic snake can form an almost accurate image in the entire screen, thereby increasing the resolution.

However, the third and fourth features do not reduce the horizontal size of the electron beam, which is increased due to the yoke aberration generated when using the self-convergence yoke, and may also cause moiré phenomenon by the vertical size of the small electron beam from which halo is removed. have.

The second feature provides an optimal shear focusing lens to the main lens weakened by the fourth feature, thereby forming a smaller electron beam on the screen.

The angle of incidence of the electron beam incident on the main lens should be reduced. The second feature is that as the intensity of the main lens decreases, it provides the best shear focusing lens to form a smaller electron beam on the screen.

As the intensity of the main lens decreases, the distance from the main lens to the object point increases and the incident angle of the electron beam incident on the main lens should decrease.

Therefore, the second feature is that as the intensity of the main lens decreases, the intensity of the focusing lens increases, so that a smaller electron beam can be obtained on the screen.

The first feature compensates for horizontal beam characteristics at the periphery of the screen, ie increased horizontal beam size and reduced vertical beam beam size, when using self-convergence yokes.

As described above, the present invention can reduce the horizontal size of the electron beam and increase the vertical size.

In addition, as the electron beam is deflected to the periphery, the voltage applied to the dynamic electrode is varied so that the intensity of the main focusing lens is synchronized with the deflection yoke so that the most suitable electron beam can be incident even if the intensity of the main lens is weakened. By changing the intensity, a smaller electron beam size can be obtained in the entire screen area, and thus the resolution can be improved.

Claims (22)

A cathode for emitting electrons, a first grid electrode for controlling the electron beam emitted from the cathode, a second grid electrode for accelerating the electron beam, and a unit for focusing and accelerating the focused electron beam to focus on a fluorescent screen surface In an inline electron gun with an electrode constituting a lens of the form and a color cathode ray in which the electrodes constituting the lens of the bi-type are sequentially arranged in the tube axis direction, at least two of the electrodes constituting the bi-type lens By dividing into electrodes, at least one of the divided electrodes is tuned to a deflection yoke so that the voltage is variable, and a constant voltage is applied to the other electrode, and the electrodes constituting the uni-type lens are at least two electrodes. The second grid side electrode, which is one of the divided electrodes, is divided and electrically connected. Electron gun for the color cathode ray tube, characterized in that the electrically connected to the electrode to which a constant voltage is applied, and the other electrode is electrically connected to the electrode to which the variable voltage is tuned to the deflection yoke of the electrodes constituting the bi-lens . The electron gun for color cathode ray tubes according to claim 1, wherein the third grid electrode of the electrodes forming the uni-lens is divided into two, and the electrode disposed on the second grid side is formed of a plate-shaped electrode. The electron gun for color cathode ray tube according to claim 1, wherein the third grid electrode of the electrodes constituting the uni-lens is divided into two, and the electrode disposed on the screen side is formed of a cap-shaped electrode. According to claim 1, wherein the third grid electrode of the electrode constituting the uni-lens is divided into two, the electrode disposed on the second grid side is formed as a plate-shaped electrode and the electrode disposed on the screen side is formed of a cap-shaped electrode Electron gun for color cathode ray tube, characterized in that. The electron gun for a color cathode ray tube according to claim 2, wherein the deflection electrode has an axisymmetric pore diameter. 4. The electron gun for a color cathode ray tube according to claim 3, wherein the cap-shaped electrode has a pore diameter in which the cathode side electrode is shorter in length than the vertical length and the screen side pore is axisymmetric. 5. The electron gun for color cathode ray tube according to claim 4, wherein the two divided electrodes are electrically connected to each other. A cathode for emitting electrons, a first grid electrode for controlling the electron beam emitted from the cathode, a second grid electrode for accelerating the electron beam, and a uni-directional for focusing and accelerating the focused electron beam to focus on a fluorescent screen surface The third grid electrode, the fourth grid electrode and the fifth grid electrode constituting the lens of the shape, and the fifth grid electrode and the sixth grid electrode constituting the bi-shape are sequentially arranged in the tube axis direction. The fifth grid electrode of the electrodes constituting the bi-type lens is divided into two or more trillion electrodes, and at least one of the divided electrodes is synchronized with a deflection yoke so that the voltage is variable and At least two of the third grid electrode among the electrodes constituting the uni-type lens are applied. The second grid side electrode, which is one of the divided electrodes, is electrically connected to an electrode to which a constant voltage is applied, and the other electrode is deflected among the electrodes constituting the bilens. An electron gun for a color cathode ray tube, characterized in that the electrode is tuned to the yoke and is variable. The electron gun for color cathode ray tube according to claim 8, wherein the electrode disposed on the screen side of the two divided third grid electrodes is formed of a cap-shaped electrode, and the electrode disposed on the cathode side is formed of a judge electrode. 10. The electron gun for color cathode ray tube according to claim 9, wherein the cap-shaped electrode has a pore diameter whose horizontal length is shorter than that of the vertical electrode, and the screen-side process is axisymmetric. The electron gun for a color cathode ray tube according to claim 9, wherein the length of the plate-shaped electrode of the third grid electrode is smaller than the length of the cap-shaped electrode. A cathode for emitting electrons, a first grid electrode for controlling the electron beam emitted from the cathode, a second grid electrode for accelerating the electron beam, and a uni-directional for focusing and accelerating the focused electron beam to focus on a fluorescent screen surface In-line of the color cathode ray tube in which the third grid electrode and the fourth grid electrode constituting the lens of the shape lens and the fifth grid electrode and the sixth grid electrode constituting the bi-shaped lens and the sixth grid electrode are sequentially arranged in the tube axis direction. In the electron gun, the fifth grid electrode of the electrodes constituting the bi-type lens is divided into at least two or more electrodes, and at least one electrode of the divided electrodes is equally deflected so as to vary the voltage and the other electrode. A constant voltage is applied to the electrodes, and the electrodes constituting the uni-type lens are at least two electrodes. The second grid side electrode, which is divided and electrically connected, is one of the divided electrodes, and the second grid side electrode is electrically connected to an electrode to which a constant voltage is applied, and the cathode side electrode is tuned to the yoke of the fifth grid electrode and is variable. An electron gun for a color cathode ray tube, characterized in that it is electrically connected to an electrode receiving a voltage. The electron gun for color cathode ray tube according to claim 12, wherein the electrode disposed on the screen side of the two divided third grid electrodes is formed of a cap-shaped electrode, and the electrode disposed on the cathode side is formed of a plate-shaped electrode. The electron gun for a color cathode ray tube according to claim 13, wherein the cap electrode has a pore diameter of which the horizontal electrode is shorter than the vertical length, and the screen side pore is axisymmetric. The electron gun for a color cathode ray tube according to claim 13, wherein an electrode length of the plate-shaped electrode of the third grid electrode is smaller than a cap-shaped electrode length. A cathode for emitting electrons, a first grid electrode for controlling an electron beam emitted from the cathode, a second grid electrode for accelerating the electron beam, and a third for focusing and accelerating to focus the accelerated electron beam on a screen surface And 5, 5, and 6 grid electrodes, wherein the fifth grid electrode is divided into two electrodes, and a plate-shaped electrode is disposed inside the cathode-side electrode, and a vertical bulkhead is installed around the pore of the plate-shaped electrode. In an inline electron gun of a color cathode ray tube having a horizontal bulkhead formed around a pore diameter, at least one of the divided fifth grid electrodes is tuned to a deflection yoke, and a voltage is applied to the other electrode. The third grid side is divided into at least two electrodes, and the second grid side electrode, which is one of the divided electrodes, is a fifth grid electrode. A constant voltage is applied is electrically connected to the electrode and the negative electrode side are color cathode-ray tubes the electron gun, it characterized in that the hayeoseo electrically connected to the electrode to receive a voltage is applied that varies is tuned to the deflection yoke of the fifth grid electrode. 17. The electron gun for color cathode ray tube according to claim 16, wherein an electrode disposed on the green side of the two divided third grid electrodes is a cap-shaped electrode, and an electrode disposed on the cathode side is formed of a plate-shaped electrode. 18. The electron gun for a color cathode ray tube according to claim 17, wherein the cap electrode has a pore on the cathode side of which the horizontal length is shorter than the vertical length, and the pore diameter on the screen side is axisymmetrical. 18. The electron gun for a color cathode ray tube according to claim 17, wherein an electrode length of the plate-shaped electrode of the third grid electrode is smaller than a length of a cap shape. A cathode for emitting electrons, a first grid electrode for controlling an electron beam emitted from the cathode, a second grid electrode for accelerating the electron beam, and a third for focusing and accelerating to focus the accelerated electron beam on a screen surface , 4, 5, and 6 grid electrodes, the fifth grid electrode is divided into two electrodes, a plate-like electrode is disposed inside the cathode-side electrode, a vertical partition wall is installed around the pore of the plate-shaped electrode, and the screen electrode In an inline electron gun of a color cathode ray tube having a horizontal bulkhead formed around a pore diameter, at least one of the divided fifth grid electrodes is tuned to a deflection yoke, and a voltage is applied to the other electrode. The third electrode is divided into at least two electrodes such as a cap-shaped electrode disposed on the screen side and a plate-shaped electrode disposed on the cathode side. The two divided electrodes are electrically connected to each other, and the second grid-side electrode, which is one of the divided electrodes, is electrically connected to the whole country where a constant voltage is applied among the fifth grid electrodes, and the cathode-specific electrode is a deflection yoke of the fifth grid electrodes. An electron gun for a color cathode ray tube, characterized in that the voltage is tuned to and electrically connected to the applied electrode. 21. The electron gun for a color cathode ray tube according to claim 20, wherein the cap-shaped electrode has a pore size in which the cathode side electrode has a short vertical length and the pore size of the screen side is axisymmetric. 21. The electron gun for color cathode ray tube according to claim 20, wherein an electrode length of the plate-shaped electrode of the third grid electrode is smaller than a cap-shaped electrode length.