KR100234053B1 - Electron gun for color braun tube - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electron gun for a color receiver, and in particular, an electron gun structure capable of improving the resolution at the periphery of a screen by correcting astigmatism according to the deflection amount of an electron beam in the structure of an electron gun used for a large TV or a high-definition industrial monitor. The purpose is to provide.

In order to realize this, in the present invention, a long hole having a vertical direction larger than the horizontal direction of the electron beam through hole is formed in the fixed voltage focusing electrode on the opposite surface of the variable voltage focusing electrode, and is formed vertically inside the fixed voltage focusing electrode outside the outer electron beam hole. The plate electrode protrudes, and an inner electrode having three electron beam through holes is inserted therein, and a vertical hole longer than horizontal has electron beam through holes in the variable voltage focusing electrode on the opposite surface of the fixed voltage focusing electrode, respectively. The plate electrodes are bent in the vertical direction above and below the electron beam through hole of the second focusing electrode, and the horizontal flat electrodes formed above and below the second focusing electrode are provided to face or be inserted into the long hole electrodes of the first focusing electrode. It is.

Description

Color gun

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color receiver, and more particularly, to an electrode structure inside an electron gun for focusing and accelerating electrons generated at a cathode to land an electron beam on a phosphor on a screen.

In general, the color water pipe includes a panel 3 having a fluorescent surface 3a coated on its inner surface, and a shadow mask 4 having a color discriminating function coupled to an inner surface of the panel 3, as shown in FIG. And a funnel (1) coupled to the rear end of the panel (3), an electron gun (6) mounted on the neck (5a) of the funnel (1), and an electron beam (9) emitted from the electron gun (6). And a deflection yoke 7 for deflecting.

And the internal structure of the electron gun 6 shown in Figure 2 is composed of a three-pole portion and the main lens, the three-pole portion is a cathode (11) that emits electrons with a heater 10 is built-in, and is radiated from the cathode (11) It consists of a control electrode 12 and an acceleration electrode 13 for controlling and accelerating the hot electrons, and the main lens portion is a focusing electrode 14 and an anode 15 for focusing and finally accelerating the electron beam 9 generated at the triode. It is composed.

Here, the control electrode 12 is grounded, a high voltage of 500 to 1000 V is applied to the acceleration electrode 13, 25 to 35 KV is applied to the anode 15, and an intermediate voltage of 20 to 30% of the anode voltage is applied to the focusing electrode 14. Is applied.

In the conventional color water tube electron gun configured as described above, as a predetermined potential is applied to each electrode, an electrostatic lens is formed by a voltage difference between the focusing electrode 14 and the anode 15. It is focused at the center of this fluorescent surface. At this time, a deflection yoke attached to the funnel 5 acts to deflect the electron beam focused at the center of the fluorescent screen to the entire screen area. In general, in the color receiving tube using an inline type electron gun, three electron beams of red, green, and blue are arranged side by side, so that the deflection yoke (7) uses a non-uniform magnetic field in order to converge the three electron beams on one side of the fluorescent surface. (Self-Convergence) is applied.

As shown in (a) and (b) of FIG. 3, the distribution of the magnetic field generated in the deflection yoke to which the self-focusing type is applied, the horizontal deflection magnetic field is a pincushion type, and the vertical deflection magnetic field is a barrel type. This prevents misalignment in the.

However, as shown in (c) (d) of FIG. 3, the magnetic field can be described by dividing the bipolar component and the quadrupole component. The bipolar component serves to deflect the electron beam in the horizontal and vertical directions. The quadrupole component focuses the electron beam in the vertical direction and diverges in the horizontal direction to generate astigmatism and distort the electron beam spot.

Even if the magnetic field is close to uniform, the fine spots and barrel magnetic components cause the electron beam to undergo significant astigmatism at the periphery of the fluorescent surface, thereby distorting the beam spot. In FIG. 4A and FIG. 4B, the distortion phenomenon of the electron beam spot is illustrated in more detail. According to FIG. 4, the electron beam spot has an accurate shape because a deflection magnetic field is not applied at the center of the screen, but at its periphery, a high-density horizontal core 17 that is dissipated in the horizontal direction and overconcentrated and distorted in the vertical direction, and low density above and below it. The generation of haze 18, which is a phenomenon of spreading, causes degradation in resolution, especially at the periphery of the screen. The problem is that the larger the water tube, or the larger the angle of deflection, the greater.

In order to improve the above problems, there are many methods for correcting astigmatism in synchronization with a deflection signal when the electron beam is deflected to the periphery of the screen. As the correction means, the focusing electrode is divided into two and the first focusing electrode and the second The astigmatism is corrected by forming a focusing electrode and forming a 4-pole lens by providing a 4-pole electrode therebetween.

The averaging correction means of the conventional embodiment will be briefly described with reference to the accompanying drawings.

In FIG. 5, the conventional configuration has a tripolar portion for generating an electron beam and a main lens for focusing the electron beam, and the focusing electrode 14 forming the main lens includes a first focusing electrode 80 and a second focusing electrode 90. It is divided into two parts. The second focusing electrode 90 faces the anode 15 and the first focusing electrode 80 faces the second focusing electrode 90. The first focusing electrode 80 has long holes 801, 802, and 803 bored in the vertical direction, and the vertical plate electrode 82 is connected to the outer outer electron beam through hole, that is, in the horizontal direction of the outer long hole (opposite to the center electron beam through hole). It extends inside this first focusing electrode. The second focusing electrode 90 is attached with a circular three-electron beam through hole (111, 112, 113) and a correction electrode 100 formed by bending the flat plate (101, 102, 103) in the vertical direction of the three electron beam through hole, the first focusing electrode (80) It protrudes in the direction. In addition, a guide inner electrode 81 is formed inside the first focusing electrode to support the first focusing electrode.

The first focusing electrode includes a vertical plate electrode 82 and a guide inner electrode 81 that are formed in the first focusing electrode 80 in a horizontal direction in an outer electron beam passing hole, that is, in an outer direction of the outer long hole (opposite to the center electron beam passing hole). Comprising an electrode, the correction electrode 100 formed by bending the flat three-electron beam through holes (111, 112, 113) formed in the second focusing electrode 90 and the plate (101, 102, 103) is bent in the vertical direction of the three electron beam through hole. To form the second focusing electrode 90.

These electrodes are the basic configuration for forming a dynamic quadrupole lens.

The operation of the prior art having the above configuration will be described below.

In order to improve the resolution of the periphery, an electron gun for a color image tube passes through the first focused electrode 80 and the second focused electrode 90 divided into two, as shown in FIG. Passed through the pole electrode portion (82,801,802,803 in Fig. 5) and the electrode on the second focusing electrode side (101,102,103 in Fig. 5) is focused in the main lens and forms an image on the tube screen. In particular, when the electron beam is deflected to the periphery, the first focusing electrode voltage is fixedly operated, but the second focusing electrode voltage changes according to the deflection amount of the electron beam. That is, the quadrupole lens is operated by the quadrupole electrode (hereinafter referred to as the quadrupole electrode).

In general, the larger the CRT or the larger the deflection angle, the higher the second focusing electrode voltage becomes than the first focusing electrode voltage. The second focusing electrode voltage is supplied in a parabolic waveform in a circuit of a TV or a monitor, and is generally applied at 300V to 1000V higher than the first focusing electrode voltage. When the second focusing electrode voltage is applied, the quadrupole lens operates due to the difference between the first focusing electrode voltage and the second focusing pole voltage, so that the shape of the electron beam changes into an elongated shape, and the non-uniformity of the deflection yoke passes through the main lens. It acts in a direction to improve the haze of the peripheral portion generated by the magnetic field. The description of the quadrupole lens is as follows.

FIG. 6A is an explanatory view showing astigmatism and beam trajectory caused by deflection yoke when the electron beam is not deflected, that is, at the center of the screen, almost exactly in the horizontal / vertical direction, but is deflected to the periphery. The deflection yoke diverges the electron beam in the horizontal direction and focuses in the vertical direction. When the electron beam is deflected to the periphery, the over-focusing component due to the distance difference and the under-focusing component due to the deflection yoke cancel each other. Although the focusing state is almost accurate, in the vertical direction, the over-focusing component due to the distance difference and the over-focusing component in the vertical direction of the deflection yoke overlap to show a severe over-focusing shape. Therefore, when the electron beam is deflected to the periphery, The spreading phenomenon in the vertical direction is severe, resulting in degradation of the peripheral resolution.

FIG. 6B is an explanatory diagram when a four-pole electrode is applied to improve such a phenomenon of spreading. The deflection yoke astigmatism caused by the quadrupole is compensated for with the same focusing force of the main lens. The four-pole lens focuses in the horizontal direction by the horizontal divergence of the deflection yoke, and the four-pole lens diverges in the vertical direction by the amount of focus in the vertical direction of the deflection yoke. This requires a main lens weakening component (i.e., a dynamic voltage), and the main lens weakening component serves to focus at the position of the peripheral portion which requires a coincident electron beam in the horizontal / vertical direction as shown in FIG. Do it. With the appropriate quadrupole lens and the applied dynamic voltage as above, it is possible to have the optimum focusing force around the screen.

In general, the voltage applied to the focusing electrode is about 20 to 33% of the anode voltage. This is a good way to make the quadrupole lens act strongly on this focusing voltage.

However, the quadrupole electrode of the conventional electron gun is composed of two electrode combinations. In the case of using two electrodes, there was a problem that the unit cost of the product increased due to problems such as welding maneuver and welding machine, mold cost of the welding process.

In the present invention, in order to solve this problem, the shape of the electron beam through-hole of the second focusing electrode is configured in the form of a keyhole, and horizontal flat electrodes are formed above and below each electron beam through-hole, so that the first focusing electrode has a predetermined interval in the direction of the first focusing electrode. It is an object to be able to correct the astigmatism according to the deflection amount of the electron beam by configuring to be opposed or inserted in the long hole direction of the focusing electrode.

1 is a cross-sectional view of a common color water pipe.

2 is a cross-sectional view showing the internal structure of the electron gun.

3 is a distribution diagram of a magnetic field generated in a conventional deflection yoke.

4 is a view showing a distortion phenomenon of a conventional electron beam spot.

5 is a detailed structural diagram of a focusing electrode part of a conventional electron gun.

6 shows a screen focusing state of an electron beam;

a is a non-dynamic state when no quadrupole lens is applied.

b is a dynamic state diagram when a 4-pole lens is applied.

7 is a detailed structural diagram of the focusing electrode part of the electron gun to which the present invention is applied;

* Explanation of symbols for main parts of the drawings

6 electron gun 9 electron beam

10 heater 11 cathode

12 control electrode 13 acceleration electrode

14: focusing electrode 15: anode

80: first focusing electrode 82: vertical flat electrode

90: second focusing electrode 100: correction electrode

104,105,106 Horizontal flat electrode 801,802,803

904,905,906: electron beam through hole

The present invention is described in detail below.

First, as shown in FIG. 7, the focusing electrode forming the main lens is divided into a first focusing electrode 80 and a second focusing electrode 90, and the second focusing electrode 90 is formed. Is opposed to the anode 15 side, and the first focusing electrode 80 is configured to face the second focusing electrode 90.

The present invention relates to a second focusing electrode, wherein the first focusing electrode 80 has long holes 801, 802, and 803 in the vertical direction, and is vertically connected to the outside of the outer electron beam through hole, that is, to the outer horizontal direction of the outer long hole. The electrode 82 extends into the first focusing electrode, and the height of the vertical plate electrode 82 formed in the outer electron beam passing hole is about 0.5 mm.

The second focusing electrode 90 has an electron beam through hole 904, 905, 906 in the shape of a key hole, and horizontal flat electrodes 104, 105, 106 are formed above and below each key hole type electron beam through hole, respectively. Direction to the first focusing electrode in the long hole direction at regular intervals in the direction or is configured to be inserted.

The characteristics of the above configuration are examined through three-dimensional simulation.

To design a DYNAMIC lens, you must first know the non-DYNAMIC state. When the voltage applied to the first focusing electrode is called a static voltage and the voltage applied to the second focusing electrode is called a dynamic voltage, the non-dynamic state is the same as the static voltage and the dynamic voltage so that the first focusing electrode and the second focusing electrode are the same. When applied to the electrode at the same time.

In such a non-dynamic state, when the non-dynamic focus voltage at which the pixel at each point (center, east, top, and corner) of the screen is minimized is measured, it can be seen that the horizontal focus voltage is almost constant at each point. As described above, the neutralizing effect of the horizontal divergence of the deflection yoke and the focusing force due to the distance difference can obtain almost the same focus voltage in the entire area of the screen.

라고 표현하고, 에지에서 센터의 값을 뺀값을

, 코너에서 센터의 값을 뺀값을

라고 할 때 이값들, 즉

,

,

은 최종적으로 개선해야할 편향요크의 수차성분이된다. (단, 수평방향은 거의 동일의 포커스전압을 유지하므로 개선해야할 수차성분으로는 넣지 않았음.)In contrast, the vertical focus voltage changes exponentially in the order of center, top, edge, and corner. The dynamic lens is designed by using the vertical focus voltage which changes exponentially in non-dynamic state. Measure the focus voltage at each point of the screen and use this value as simulation data. From the focus voltage at the top point, subtract the focus voltage from the center.

And subtract the center from the edge

, Subtract the center value from the corner

Are these values,

,

,

Becomes the aberration component of the deflection yoke that should be finally improved. (However, the horizontal direction maintains almost the same focus voltage, so it is not included as aberration component to be improved.)

,

,

을 컴퓨터에 입력하여 메인렌즈 출구에서(즉, 양극전극 끝단) 전자빔 반경, 발산각, 포커스 길이를 기본 목표치로 삼는다. 그리고 다이나믹전압을 인가하였을 때 전자빔 반경, 발산각, 포커스 길이 상태가 동일하게 되도록 설계하면된다.In this non-dynamic state, ie V _C (focusing voltage at the screen center),

,

,

Is input to the computer and the electron beam radius, divergence angle and focal length at the exit of the main lens (i.e. the anode end) are the primary targets. When the dynamic voltage is applied, the electron beam radius, divergence angle, and focal length may be the same.

,

,

값의 1/2정도가 되도록 한다.Dynamic voltages need to be finally improved

,

,

It should be about 1/2 of the value.

In other words, (a) of FIG. 6 shows that when the electron beam is not deflected, that is, at the center of the screen, it is almost exactly focused in the horizontal / vertical direction, but when the electron beam is deflected, the deflection yoke diverges the electron beam horizontally and in the vertical direction. Serves to focus. As a result, as described above, when the electron beam is deflected to the periphery, the over-focusing component due to the distance difference and the under-focusing component due to the deflection yoke cancel each other, indicating a nearly accurate focusing state. Due to the overlap of over-focusing component and vertical over-focusing component of deflection yoke, it shows severe over-focusing phenomenon. Therefore, when the electron beam is deflected to the periphery, the phenomenon of superimposition in the vertical direction of the electron beam is severe. Bring. When the quadrupole electrode of the present invention is applied in order to improve the above spreading phenomenon, the deflection yoke astigmatism caused by the quadrupole is compensated with the same focusing force of the main lens. The quadrupole lens focuses in the horizontal direction by the horizontal divergence of the deflection yoke, and the quadrupole lens diverges in the vertical direction by the amount of focus in the vertical direction of the deflection yoke. Here, the main lens weakening component (ie, the dynamic voltage) is required, and this main lens weakening component serves to focus at the position of the periphery requiring the coincidence electron beam in the horizontal / vertical direction as shown in FIG. do. With the appropriate quadrupole lens and the applied dynamic voltage as above, it is possible to have the optimum focusing force around the screen.

As described above, the electron gun electrode structure of the present invention has an effect of improving the resolution at the periphery of the screen by correcting astigmatism according to the deflection amount of the electron beam.

Claims (2)

A plurality of focusing means for forming a plurality of electron-spinning means for emitting an electron beam, a three-pole portion consisting of a control electrode and an acceleration electrode for controlling the radiation amount and crossover of the electron beam, and a capacitive focusing lens for focusing the electron beam An electrode and an anode electrode, wherein the plurality of electron radiating means and the plurality of electrodes are spaced apart from each other by a predetermined voltage, and a fixed voltage focusing electrode is formed by applying a fixed voltage to at least one of the plurality of focusing electrodes. An electron gun for a color cathode ray tube in which a variable voltage focusing electrode is formed by applying a variable voltage varying in accordance with an electron beam deflection amount to at least one of the plurality of focusing electrodes, wherein the fixed voltage focusing electrode on the opposing surface of the variable voltage focusing electrode is provided. An electron beam through hole having a larger vertical direction than a plurality of horizontal directions is formed. A vertical plate electrode formed inside the fixed voltage focusing electrode protrudes in the horizontal direction outside the magnetic beam hole, and an inner electrode having three electron beam through holes is inserted therein, and the variable voltage focusing electrode on the opposite surface of the fixed voltage focusing electrode. There are a plurality of vertical holes longer than the horizontal has an electron beam through hole, the plate electrode is bent in the vertical direction above and below each electron beam through hole is formed in series with the variable voltage focusing electrode, the horizontal formed above and below the variable voltage focusing electrode The flat electrode is a color water pipe electron gun, characterized in that provided with the long hole electrode of the fixed voltage focusing electrode facing each other or inserted. The electron gun for a color water pipe according to claim 1, wherein the electron beam passing hole of the second focusing electrode is formed in a keyhole shape.

Images