KR100439263B1 - A Electron Gun Of The Color Cathode Ray Tube - Google Patents

Abstract

According to the present invention, a plurality of electron radiating means for radiating an electron beam, a three-pole portion consisting of a control electrode and an acceleration electrode for adjusting and controlling the radiation amount of the electron beam, and a plurality of electrodes for focusing and accelerating the electron beam on a screen In the color water tube electron gun comprising a plurality of electron emitting means and a plurality of electrodes are sequentially arranged in the direction of the tube axis spaced apart from each other at a predetermined interval, the control electrode or acceleration electrode of a single plate of the electrodes forming the three-pole portion An asymmetrical slot having a different width and length is formed around the electron beam through hole, and the inclination angle of the slot in the thickness direction with respect to the tube axis in the narrow slot width is at least 70 °.

According to the present invention, in forming an asymmetrical slot around an electron beam through hole in a control electrode or an acceleration electrode forming a tripolar portion of an electron gun, the inclination angle of the slot with respect to the tube axis is increased to reduce the horizontal size of the pixel and increase the vertical size to increase the resolution. There is an effect that can improve and improve the moire properties.

Description

A Electron Gun Of The Color Cathode Ray Tube}

The present invention relates to an electron gun for a color cathode ray tube, and in particular, in order to prevent resolution deterioration at the periphery of the screen, an asymmetric lens is formed at the triode of the electron gun so that the deflection aberration is reduced at the center of deflection, thereby improving peripheral resolution and spot size. In order to reduce the diameter of the control electrode (G1) to form a slot around the hole, in particular, it relates to an electron gun for a color water pipe in which the angle of the slot thickness direction is increased.

1 is a cross-sectional view showing a schematic configuration of a general color water pipe. The color receiving tube 1 includes a fluorescent surface 6 coated with red, green, and blue phosphors on the front inner surface, a panel 3c to which a shadow mask 2 having color discrimination function is connected, and a skirt portion of the panel 3c. A tubular neck portion 3a is formed at the rear of the funnel 3b and the funnel 3b to be joined. An electron gun 5 is embedded inside the neck portion 3a of the funnel 3b, and a deflection yoke 7 for deflecting the electron beam 4 emitted from the electron gun in the horizontal direction or the vertical direction is coupled thereto.

FIG. 2 is a cross-sectional view showing a general electron gun 5 for a color water pipe, and includes a cathode 11 in which a heater 10 is embedded and an inline array, a control electrode 12 for controlling and accelerating hot electrons radiated from the cathode, and an acceleration electrode ( 13) and a main lens portion composed of a focusing electrode 14 and an anode 15 for focusing and finally accelerating the electron beam 9 generated at the three poles. Here, the control electrode 12 is grounded, a high voltage of 500 to 1000 V is applied to the accelerating electrode 13, 25 to 35 kv is applied to the anode 15, and the middle of 20 to 30% of the anode voltage is applied to the focusing electrode 14. Voltage is applied.

In the conventional color water tube electron gun configured as described above, an electrostatic lens is formed by the voltage difference between the focusing electrode 14 and the anode 15 as a predetermined potential is applied to each electrode. ) Is focused in the center of the fluorescent surface. At this time, the deflection yoke 7 attached to the funnel 3b acts to deflect the electron beam focused at the center of the fluorescent screen to the entire screen area. Usually, in the color water tube using an in-line electron gun, since the three electron beams of red, green, and blue are arranged side by side horizontally, the deflection yoke 7 is non-uniform in order to converge the three electron beams on one side of the fluorescent surface. Self-Convergence using magnetic field is applied.

Although the distribution of the magnetic field generated in the deflection yoke to which the self-focusing type is applied is not shown, the horizontal deflection magnetic field is a pincushion type and the vertical deflection magnetic field is a barrel type. to prevent convergence.

However, the magnetic field can be described by dividing into two-pole and four-pole components, the two-pole component serves to deflect the electron beam in the horizontal and vertical directions, the four-pole component focuses the electron beam in the vertical direction and the horizontal direction By dissipating, the astigmatism is generated to distort the electron beam spot.

Even if the magnetic field is close to uniform, the electron beam is markedly astigmatized at the periphery of the fluorescent surface due to the fine pincushion or barrel magnetic component, which distorts the beam spot.

Since the deflection magnetic field is not applied at the center of the screen, the electron beam spot has an accurate shape as shown in 4a of FIG. 1, but at its periphery, as shown in 4b of FIG. 1, a high density dissipated in the horizontal direction and overconcentrated and distorted in the vertical direction is shown. The horizontal core of and a haze (FIG. 4B), which is a phenomenon of low density up-and-down spreading up and down, are caused to cause resolution deterioration, especially in the periphery of the screen.

The problem is that the larger the water tube, or the larger the angle of deflection, the greater.

The above-mentioned peripheral spreading phenomenon is caused by receiving a lot of deflection aberration at the center of the deflection yoke, and the horizontal direction at the deflection center of the electron beam cancels the divergence force of the deflection magnetic field and the focusing force due to the distance difference and is almost exactly However, it is necessary to adjust the electron beam at the triode in order to reduce haze at the periphery caused by overlapping of focusing force due to deflection aberration and focusing force due to distance difference in the vertical direction.

To solve this problem, many patents have been disclosed, and only a few of them are listed. Japanese Patent Publication No. 60-34783 shows a method of forming a slot in at least one of the control electrode G1 and the acceleration electrode G2. . This aim is to minimize the deflection aberration when the electron beam generated at the triode of electron beam passes through the deflection center.

Japanese Patent Laid-Open No. 7-29511 has a vertical width of a slot formed in the electron beam through hole smaller than the size of the electron beam through hole. The deeper than the depth of the outer slot, Japanese Patent Laid-Open No. Hei 4-249837 has an asymmetric prefocus lens and an asymmetric main lens or a cathode lens.

U.S. Patent 4,641,058 has a vertically stronger lens than the horizontal and the main lens has a stronger main than the vertical. The U.S. Patent No. 4,886,998 has a slot forming surface having a thickness of 0.4 to 1.0 times the pore diameter and having a slot formed therein. In order to make the thickness of 0.1 to 0.2 times the pore diameter, US Patent 4,358,703 forms a longitudinal slot on the G2 side surface of the electrode G1, and US Patent 4,558,253 is a prefocus composed of an asymmetric BFR, an asymmetric main lens, and three electrodes. In the U.S. Patent No. 4,629,933, a vertical slot is formed on the G1 electrode surface opposite to the electrode G2, and the G1 pore is formed in a square.

These patents are mainly used to reduce the deflection aberration at the periphery and to reduce the electron beam in high current situations at the center or periphery of the screen.

In the color image tube electron gun for improving the resolution of the periphery, the electron beam generated in the tripolar portion (beamforming region) passes through the quadrupole electrode portion, that is, the slot portion, is focused on the main lens and forms an image on the screen. In general, the larger the cathode ray tube or the larger the deflection angle, the more deflection aberration.

In general, slots are used to form an asymmetric triode. For example, US Pat. No. 4,886,998 describes the thickness of the slot forming surface of the second grid electrode (acceleration electrode) (ie the thickness around the ball) of 0.4 to 1.0 times the pore diameter, and the slot. The method of making the thickness of this formed part into 0.1 to 0.2 times the pore diameter is disclosed.

The electron beam generated at the triode of the electron gun is lateralized as much as possible so that the electron beam receives less deflection aberration at the center of deflection, thereby improving the haze component at the periphery. Is increased and the size of the vertical pixels on the screen is increased, resulting in resolution degradation.

In order to minimize the spherical aberration of the main lens, the tripolar portion sends an electron beam to the paraxial axis of the main lens and the center electron beam to the outside of the main lens to minimize spherical aberration, thereby improving the resolution of the center of the screen. A method for improving the effect has been proposed.

As shown in FIGS. 4 and 5, ART is a technology for mainly focusing on the electrode G2-G3, which is a prefocus lens, to send the outermost electron beam to the paraxial, mainly reducing Φ G3 and reducing the electrode G2-G3 gap to improve focusing power. Make it strong

In this configuration, since the outermost electron beam is directed to the paraxial axis and the electron beams are gathered in almost one place as in FIGS. 4 and 5, the spot becomes small.

Another method for improving the ART effect is to enhance the focusing force in the electrode G1-G2 gap.

This method forms a vertical slot around the ball of the control electrode as shown in FIGS. 3A and 3B. Although not shown, a method of configuring the pore size of the control electrode to have a horizontal quadrangular shape has been proposed. This method mainly adopts a method of welding and fixing two plates by forming a plate shape between a vertical hole electrode forming a vertical slot and a horizontal rectangular hole electrode forming an electron beam through hole.

However, when the control electrode is made of two plates as in the above-described method, there is a problem that an initial current imbalance occurs due to an imbalance of thermal change due to welding, and an increase in cost due to an increase in parts and a man-hour of welding.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-described problems, and to provide an electron gun for a color water tube having a structure that can improve ART effect and can be manufactured at low cost.

Another object of the present invention is to provide an electron gun for a color water pipe which can prevent a phenomenon in which an initial current imbalance occurs due to an imbalance of a thermal change caused by welding.

1 is a cross-sectional view showing a structure of a general color water pipe;

2 is a cross-sectional view showing the structure of a general electron gun,

3A and 3B are a plan view and a sectional view of the control electrode structure of FIG. 2, respectively;

4 illustrates the principle of ART effect in an electron gun;

5 is a view showing a beam forming principle of an electron gun triode;

6 is a cross-sectional view showing a beam shape incident on the main lens according to the angle of the conventional asymmetric slot

7 is a cross-sectional view showing a beam shape incident on the main lens according to the angle of the asymmetric slot of the present invention;

8 is a view showing a relationship between an angle of an asymmetric slot and an electron beam divergence angle;

9 is a view showing a relationship between an electron beam divergence angle and an electron beam radius; and

10 and 11 are diagrams illustrating the relationship between the electron beams focused on the main lens according to the size of the electron beam incident on the main lens in the electron guns of the prior art and the present invention, respectively.

*** Explanation of symbols for the main parts of the drawing ***

1: color cathode ray tube 2: shadow mask

3a: neck portion 3b: funnel

3c: panel 4: electron beam

5: electron gun 6: fluorescent surface

7: deflection yoke 10: heater

11: cathode 12: control electrode

13: acceleration electrode 14, 15: main electrode

Technical solution of the present invention for achieving the above object, a screen comprising a plurality of electron emitting means for emitting an electron beam, a triode consisting of a control electrode and an acceleration electrode for adjusting and controlling the radiation amount of the electron beam, and the electron beam In the color water tube electron gun including a plurality of electrodes for performing the focusing and acceleration in the, wherein the plurality of electron emitting means and the plurality of electrodes are sequentially arranged in the direction of the tube axis spaced apart from each other by a predetermined interval, the electrode forming the tripolar portion Among them, a control plate or acceleration electrode of a single plate is formed with an asymmetrical slot having a width and a vertical width around the electron beam passing hole, and the angle of inclination of the slot in the thickness direction with respect to the tube axis in the direction of narrow slot width is 70 °. It is characterized by the above.

Hereinafter, the configuration of the electron gun according to the present invention will be described in detail with reference to the accompanying drawings.

3B and 6 illustrate a structure in which an elongated slot is formed around a hole through which an electron beam passes in a control electrode (first grid electrode) or acceleration electrode (second grid electrode) of a conventional electron gun triode. At this time, the slot is elongated, asymmetrical in the width and length of each other, as shown in Figure 3b and 6, the thickness direction of the slot with respect to the tube axis is designed to 45 °. The design of the slot in the thickness direction with respect to the tube axis is 45 ° or less because it is easy to manufacture slots that do not penetrate on a single plate.

As shown in FIG. 7, the present inventors have examined the thickness angle of the slot axis to maximize the ART effect.

In order to enhance the ART effect, in order to enhance the focusing force between the acceleration electrode (hereinafter referred to as 'G2 electrode') and the main focusing electrode (hereinafter referred to as 'G3 electrode'), the hole size of the G3 electrode is mainly reduced, that is, Φ1. There is a method to reduce the 5mm hole by Φ0.90mm and to increase the ART effect by reducing the G2-G3 gap, and the second is to strengthen the focusing force between the control electrode (hereinafter referred to as 'G1 electrode') and G2 electrode There is a direction to increase the ART effect, the present invention specifically employed a method for increasing the ART effect between the G1, G2 electrodes.

6 to 10 are schematic views showing the effect of ART for each angle of the slot.

FIG. 6 shows a conventional ART effect, and FIG. 7 shows an ART effect in a state where a slot angle is 70 ° or more.

In FIG. 6, a phenomenon in which the lens gradient becomes larger than the conventional gap between the electrodes G1-G2 gap due to the G2 voltage is generated, which causes the electron beam to focus toward the paraxial axis. 8, 9, 10, and 11, the beam diameter decreases before the main lens is incident, and the outermost electron beams have a smaller beam diameter and a divergence angle, as shown in FIGS. 8, 9, 10, and 11.

As shown in FIG. 8, when the angle of the slot of the control electrode is increased, as the angle of the outer electron beam increases, the change in the angle of the paraxial electron beam decreases, but the angle of the outer electron beam decreases significantly.

Thus, at around 70 °, the divergence angle radiates in the opposite direction to the paraxial electron beam. That is, it can be seen that the electron beam is directed to the paraxial axis of the main lens.

Therefore, as shown in FIG. 9, the beam diameter is reduced compared to the conventional one, and the outer electron beams can be seen that the radius of the electron beam is reduced and the divergence angle is reduced to operate at the paraxial axis of the main lens.

In fact, it is impossible to manufacture a slot angle of 90 ° or more. Therefore, in order to obtain better characteristics, it is necessary to design using a different factor. Because, when the angle of the slot is set to 90 °, the phenomenon occurs that the electrode parts come with the mold punch during the mold processing, which is a structure vulnerable to dimensional deformation.

Therefore, the inner width and the outer width should always be larger than the inner width, so the slot angle should be designed with more than 70 ° and less than 90 °.

As a result, the slot angle is designed to be 70 ° or more, unlike the conventional 45 ° or less, thereby reducing the beam size on the screen by about 10% by changing the path of the outer electron beam to the paraxial axis.

According to the simulation results, it is understood that the thickness of the slot is thick, and in particular, the angle of the slot should be large.

In addition, in the present invention, when the thickness of the slot forming surface (that is, the thickness around the hole) is 0.4 to 1.0 of the pore diameter, the thickness of the slotted portion is 0.1 to 0.2 times the pore diameter, and the shape of the G1 electrode is applied to the horizontal shape, the effect is further increased. Is increased.

As described above, according to the present invention, the horizontal size of the pixel may be reduced and the vertical size may be increased to significantly improve resolution and moiré characteristics.

Claims (3)

A color comprising a plurality of electron emitting means for emitting an electron beam, a tripole portion consisting of a control electrode and an acceleration electrode for adjusting and controlling the radiation amount of the electron beam, and a plurality of electrodes for focusing and accelerating the electron beam on the screen In the electron gun for the water tube, The plurality of electron radiating means and the plurality of electrodes are sequentially arranged in the direction of the tube axis spaced apart from each other by a predetermined distance, the width of the horizontal and vertical around the electron beam through hole in the control electrode or the acceleration electrode of a single plate of the electrodes forming the tripolar portion The other asymmetrical slot is formed, and the thickness inclination angle of the slot with respect to the tube axis in at least the slot width direction is 70 degree or more, The gun for color water tube characterized by the above-mentioned. The method of claim 1, The thickness of the slot forming surface (that is, the thickness around the hole) is 0.4 to 1.0 times the electron beam passing pore diameter, and the thickness of the portion where the slot is formed is 0.1 to 0.2 times the electron beam passing pore diameter. The method of claim 1, The electron beam passing hole of the control electrode is a horizontal horizontal electron gun for the color water pipe, characterized in that the horizontal small vertically.