KR100234061B1 - An electron gun for color cathode ray 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 achieve this, the present invention is configured such that the height of the horizontal plate electrode formed above and below the center electron beam through hole of the correction electrode attached to the second focusing electrode is higher than the height of the horizontal plate electrode formed above and below the outside electron beam through hole. An electrode configuration is provided.

Description

An electron gun for color cathode ray tube}

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 receiver 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 heater 11 is built-in and emits electrons and the cathode 11 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) of FIG. 3, the magnetic field generated in the deflection yoke to which the self-focusing type is applied has a horizontal deflection magnetic field as a pincushion type and a vertical deflection magnetic field as a barrel type, thereby forming a fluorescent surface. This prevents misalignment in the.

However, as shown in FIG. 3C, 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, the distortion of the electron beam spot is shown 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 the periphery thereof, a high-density horizontal core 17 that is dissipated in the horizontal direction and over-condensed in the vertical direction, and has a low density up and down. 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, a number of methods for correcting astigmatism in synchronism with a deflection signal when the electron beam is deflected to the periphery of the screen have been adopted. And the second focusing electrode 90, and a 4-pole electrode is formed between the two to form a 4-pole lens to correct astigmatism.

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

As shown in Fig. 5A, the conventional electron gun has a tripolar portion for generating an electron beam and a main lens for focusing the electron beam, and the focusing electrode 14 for forming the main lens is divided into two. The first focusing electrode 80 and the second focusing electrode 90, the second focusing electrode 90 is opposed to the anode 15 side, the first focusing electrode 80 is the second focusing electrode 90 Configure to face Long holes 801, 802, 803 larger than the horizontal are formed in the first focusing electrode 80. In particular, the vertical bulkhead electrode 82 is disposed outside the outer electron beam through-holes 801, 803. A guide inner electrode 81 having three electron beam through holes is installed in the first focusing electrode 80, and three electron beam through holes 901, 902, 903 are provided in the second focusing electrode 90. The horizontal plate electrodes 101, 102, and 103 are installed in the direction of the first focusing electrode 80 to be inserted into or opposed to the first focusing electrode 80.

Another conventional configuration has a tripolar portion for generating an electron beam and a main lens for focusing the electron beam, as shown in FIG. 5 (b), and the focusing electrode 14 for forming the main lens includes: a first focusing electrode 80; The second focusing electrode 90 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. Long holes vertically larger than the horizontal are formed in the first focusing electrode 80, and vertical barrier electrodes 82 are disposed outside the outer electron beam passing holes, and the second focusing electrode 90 has a combination of a circle and a square hole. The horizontal plate electrodes 104, 105, and 106 are bent in the vertical direction of the three-hole electron beam through holes 904, 905, 906 and the three electron beam through holes formed in the direction of the first focusing electrode 80. Protrudes. In addition, a guide inner electrode 81 is formed inside the first focusing electrode to support the first focusing electrode.

The color gun tube for improving the resolution of the peripheral portion passes through the focusing electrode 80 and the second focusing electrode 90 in which the electron beam generated in the three-pole portion is divided into two, and in particular, the four-pole electrode portions 82,801 to 806 and The second focusing electrode passes through the quadrupole electrodes 101 to 106 on the electrode side, is focused by the main lens, and forms an image on the screen. In particular, when the electron beam is deflected to the periphery, the first focusing electrode voltage (static voltage) is fixedly operated, but the second focusing electrode voltage (dynamic voltage) changes according to the amount of deflection of the electron beam. That is, the quadrupole lens is operated by 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 from 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, due to the difference between the first focusing electrode voltage and the second focusing electrode voltage, the quadrupole lens is operated to change the shape of the electron beam into an elongated shape and the non-uniformity of the deflection yoke through the main lens. It serves to improve the haze of the peripheral portion generated by the magnetic field. The description of the quadrupole lens is as follows.

6A shows that when the electron beam is not deflected, that is, when the electron beam is deflected to the periphery almost exactly in the horizontal / vertical direction at the screen center, this is not the case. 6A is an explanatory diagram showing astigmatism and beam trajectory caused by the deflection yoke when 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 and show severe over-focusing phenomenon. 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 in order to improve such spreading phenomenon. The state where the deflection yoke astigmatism caused by the quadrupole is compensated for with the same focusing force of the main lens is shown. 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. 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 where the coincidence electron beam is required in the horizontal / vertical direction as shown in (b) of FIG. 6. 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.

In general, the quadrupole electrode is not only applied to any one model, but may be applied to color water tubes of various sizes. The design of the quadrupole electrode can be designed differently according to the focusing voltage ratio. In this way, the simplest design method for applying to models having different focusing voltage ratios is possible by adjusting the depths d ₁ , d ₂ , and d _{3 of the} guide inner electrode 81 installed inside the first focusing voltage electrode. Do. The focusing voltage applied to the focusing electrode 14 is about 20 to 30% of the anode voltage. When the focusing voltage ratio is low, the ACTION of the quadrupole electrode may be weak, but when the focusing voltage is high, the lens diameter becomes large because the main lens is weakened. Therefore, the 4-pole lens ACTION is insensitive. To be insensitive is to be insensitive to assembly errors, but the quadrupole lens ACTION must be strong. In order to apply the conventional electron gun to a model having a low focusing electrode voltage ratio, the size of the electron beam pixel was measured while deepening the depth of the guide inner electrode 81, which is the easiest method, and the result as shown in FIG.

In general, the design goal of the quadrupole electrode is first, the horizontal focusing voltage of the electron beam, that is, the voltage applied to the first focusing electrode (fixed voltage) equally in the entire area of the screen, the vertical focusing voltage of the electron beam The voltage applied to the second focusing electrode may be designed to be applied in the same manner as the parabolic waveform in the driving circuit. Of course, it should increase at the same ratio of three electron beams R (170,173), G (171,174), and B (170,173).

However, when the depth of the guide inner electrode 81 is increased, a phenomenon as shown in FIG. 9B occurs. 9 (b) increases the depth of the guide inner electrode at the corner of the screen [d ₁ , d ₂ , d ₃ of FIG. 5 (a), d ₄ , d ₅ , d of (b) of FIG. _6, the d _11, of (a) of Figure 7, d _31, is a phenomenon at the time sikyeoteul also optimize the increase] by R (173), B (173 ) to d _41, d ₆₁ in (B) of 7. In this case, the first focusing electrode voltage (V _S 174) in the horizontal direction of a central electron beam (174) is R (173), a first focusing electrode voltage (V _S 173) in the horizontal direction of the B (173) gradually go to prepare a corner Lowers. Of course, the second focusing electrode voltage V _d 174 of the G electron beam at this time is higher than R and B. Due to this phenomenon, as shown in (b) of FIG. 9, the shape of the G electron beam is increased in size, resulting in an electron beam that is horizontally enlarged compared to R and B, which causes a resolution degradation in the peripheral portion.

The present invention has been invented to solve the problems of the prior art as described above, the height of the horizontal plate electrode formed above and below the center electron beam through hole of the correction electrode attached to the second focusing electrode above and below the outside electron beam through hole. It is intended to correct the astigmatism according to the deflection amount of the electron beam and to improve the resolution at the periphery of the screen, by configuring the height of the formed horizontal flat electrode.

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

2 is a structural diagram of a typical electron gun electrode.

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.

Figure 5 (a) (b) is an embodiment showing a detailed structure of the focusing electrode portion of the conventional electron gun.

6 shows a screen focusing state of an electron beam;

(A) is a non-dynamic state diagram when no 4-pole lens is applied.

(B) is dynamic diagram when applying 4-pole lens.

Figure 7 (a) (b) is a detailed structural diagram and another embodiment of the focusing electrode unit of the electron gun to which the present invention is applied, respectively.

8 is an embodiment of a guide inner electrode according to the present invention.

9A is a distribution state diagram of focusing voltages depending on screen positions;

(B) is a state diagram showing the lateralization phenomenon of the conventional G electron beam.

(C) is a state diagram showing the focused state of the electron beam according to the present invention.

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

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 81: guide inner electrode

82: vertical flat electrode 90: second focusing electrode

100: correction electrode

101,102,103,104,105,106: horizontal flat electrodes

801,802,803

901,902,903,904,905,906: electron beam through hole

The present invention is described in detail below with reference to FIG.

The resolution deterioration of the central electron beam, that is, the G electron beam, is caused by the fact that the force of the quadrupole electrode acting on the G electron beam is weaker than that of R and B as the guide inner depth becomes deeper. Find a way to do it.

First, as shown in FIG. 7A, the height of the horizontal flat electrode 102 formed above and below the central electron beam through hole 902 of the correction electrode 100 attached to the second focusing electrode 90 is shown. L ₂₁ is configured to be higher than the heights L ₁₁ and L ₃₁ of the horizontal plate electrodes 101 and 103 formed above and below the outer electron beams R and B through holes 901 and 903. At this time, the length of the guide inner electrode 81 and the horizontal compensation electrode is d ₁₁ , d ₃₁ compared to the prior art (d ₁ , d ₂ , d ₃ ) and becomes d ₁₁ , d ₃₁ > d ₂₁ . In other words, the height L ₂₁ of the horizontal flat plate correction electrode above and below the center electron beam through hole of the correction electrode attached to the second focusing electrode is greater than the height L ₁₁ and L ₁₃ of the horizontal plate correction electrode above and below the outside electron beam through hole. . In other words, L ₁₁ , L ₂₁ > L ₂₁

In general, if you look at the sensitivity of the four-pole electrode main factors,

Classification (when increase) Length of horizontal flat electrode of calibration electrode Internal vertical flat electrode of the first focusing electrode Guide Inner Electrode Depth Vertical field width of the first focusing electrode Distance between the first focusing electrode and the second focusing electrode Horizontal focusing force House House Foot mountain - House Vertical focusing force Foot mountain Foot mountain House - mountain Sensitivity 40% 6% 12% 30% 12%

The above data is a phenomenon when changing in the direction of increasing the dimension of each factor per mm. Since the height of the horizontal flat electrode of the central electron beam is increased, the focusing force is increased horizontally and the diverging force is increased vertically, thereby increasing the four-pole lens force. In addition, as the result of the guide inner depth becomes closer, the horizontal divergence force becomes weaker (that is, the four-pole lens force becomes stronger), and the focusing force in the vertical direction becomes weaker. The dipole lens becomes stronger. As a result, the electron beam shown in FIG. 9C can be realized.

As shown in (a) of FIG. 7, the height of the horizontal plate electrode is higher than the height of the horizontal plate electrode above and below the outer electron beam through hole, thereby improving the resolution.

FIG. 8 shows that the central electron beam passing holes 814 and 815 of the guide inner 81 are vertically larger than the horizontal, so that the middle-long electron beam receives horizontal focusing power vertically to make the central electron beam the same as the outer electron beam. . The shape of the central electron beam through hole is a keyhole electron beam through hole formed by combining a circle and a vertical rectangle as shown in FIG. As shown in (b) of FIG. 8, the shape of the central electron beam passing hole is configured as an elliptical pore having a vertical height larger than the horizontal. In Fig. 8C, the shape of the central electron beam through-hole is constructed so that the vertical is rectangular rather than horizontal.

As described above, the electron gun structure of the present invention improves the resolution at the periphery of the screen by making it possible to correct astigmatism according to the deflection amount of the electron beam.

Claims (14)

A plurality of focusing means for forming a plurality of electrospinning means for emitting an electron beam, a tripole 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 at a predetermined interval, and a fixed voltage focusing electrode is formed by applying a fixed voltage to at least one of the plurality of focusing electrodes. A variable voltage focusing electrode is applied to at least one of the plurality of focusing electrodes in accordance with an electron beam deflection amount to form a variable voltage focusing electrode, and the fixed voltage focusing electrode on the opposing surface of the variable voltage focusing electrode has a vertical direction more than a plurality of horizontal directions. Large electron beam through hole is formed and fixed in the outer horizontal direction of the outer electron beam hole A vertical plate electrode formed inside the pressure focusing electrode protrudes, and an inner electrode having a 3-electron beam passing hole is inserted therein, and a plurality of vertical holes longer than horizontal are inserted into the variable voltage focusing electrode on the opposite surface of the fixed voltage focusing electrode. And a flat electrode bent in a vertical direction above and below each electron beam long hole, and formed on the variable voltage focusing electrode, and the horizontal flat electrode formed above and below the variable voltage focusing electrode is the fixed voltage focusing electrode. In the electron gun for color cathode ray tube which is opposed to or inserted into the long hole electrode of The height of the horizontal plate electrode above and below the long hole of the variable voltage focusing electrode is different from the height of the horizontal plate electrode formed above and below the center electron beam through hole. The method of claim 1, And the height of the horizontal plate electrodes above and below the long hole of the variable voltage focusing electrode is higher than the height of the horizontal plate electrodes formed above and below the outer electron beam through hole. 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 at a predetermined interval, and a fixed voltage focusing electrode is formed by applying a fixed voltage to at least one of the plurality of focusing electrodes. A variable voltage focusing electrode is formed by applying a variable voltage varying according to the electron beam deflection amount to at least one of the plurality of focusing electrodes, and the fixed voltage focusing electrode on the opposing surface of the variable voltage focusing electrode has a vertical direction more than a plurality of horizontal directions. A large electron beam through hole is formed and a fixed voltage in the outer horizontal direction of the outer electron beam long hole. A vertical plate electrode formed inside the focusing electrode protrudes, and an inner electrode having a 3-electron beam passing hole is inserted therein, and a variable voltage focusing electrode on the opposite surface of the fixed voltage focusing electrode has a plurality of circular electron beam passing holes. In the electron beam long hole through the hole is a correction electrode having a flat electrode bent in the vertical direction is attached, the correction electrode is a color cathode ray tube electron gun which is opposed to or inserted into the long hole electrode of the fixed voltage focusing electrode, The height of the horizontal plate electrodes above and below the long hole of the variable voltage focusing electrode is different from the height of the horizontal plate electrodes formed above and below the center electron beam through hole to be different from the height of the horizontal plate electrodes formed above and below the outer electron beam through hole. The method of claim 3, wherein And the height of the horizontal plate electrodes above and below the long hole of the variable voltage focusing electrode is higher than the height of the horizontal plate electrodes formed above and below the outer electron beam through hole. The method of claim 3, wherein The shape of the center hole of the guide inner electrode has a vertical perpendicular to the horizontal gun electron gun, characterized in that provided. The method of claim 5, The center hole of the guide inner electrode is formed in the form of a keyhole which is a combination of a circle and a rectangle, the color water pipe electron gun. The method of claim 5, An electron gun for a color water pipe, characterized in that the center hole of the guide inner electrode has a rectangular shape. The method of claim 5, An electron gun for a color water pipe, characterized in that the center hole shape of the guide inner electrode is elliptical. 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 at a predetermined interval, and a fixed voltage focusing electrode is formed by applying a fixed voltage to at least one of the plurality of focusing electrodes. A variable voltage focusing electrode is formed by applying a variable voltage varying according to the electron beam deflection amount to at least one of the plurality of focusing electrodes, and the fixed voltage focusing electrode on the opposing surface of the variable voltage focusing electrode has a vertical direction more than a plurality of horizontal directions. A large electron beam through hole is formed and a fixed voltage in the outer horizontal direction of the outer electron beam long hole. A vertical plate electrode formed inside the focusing electrode protrudes, and an inner electrode having a 3-electron beam passing hole is inserted therein, and a variable voltage focusing electrode on the opposite surface of the fixed voltage focusing electrode has a plurality of vertical holes longer than horizontal. And having an electron beam through hole, and above and below each electron beam long hole, a flat plate electrode is bent in a vertical direction to be connected to a variable voltage focusing electrode, and a horizontal flat electrode formed above and below the variable voltage focusing electrode is formed of the fixed voltage focusing electrode. In an electron gun for a color cathode ray tube facing or inserted into a long hole electrode, And a ratio (horizontal / vertical) of the horizontal diameter and the vertical size of the electron beam through hole of the guide inner electrode is greater than the horizontal / vertical ratio of the outer electron beam through hole. 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 at a predetermined interval, and a fixed voltage focusing electrode is formed by applying a fixed voltage to at least one of the plurality of focusing electrodes. A variable voltage focusing electrode is formed by applying a variable voltage varying according to the electron beam deflection amount to at least one of the plurality of focusing electrodes, and the fixed voltage focusing electrode on the opposing surface of the variable voltage focusing electrode has a vertical direction more than a plurality of horizontal directions. A large electron beam through hole is formed and a fixed voltage in the outer horizontal direction of the outer electron beam long hole. A vertical plate electrode formed inside the focusing electrode protrudes, and an inner electrode having a 3-electron beam passing hole is inserted therein, and a variable voltage focusing electrode on the opposite surface of the fixed voltage focusing electrode has a plurality of circular electron beam passing holes. In the electron beam long hole through the hole is a correction electrode having a flat electrode bent in the vertical direction is attached, the correction electrode is a color cathode ray tube electron gun which is opposed to or inserted into the long hole electrode of the fixed voltage focusing electrode, And a ratio (horizontal / vertical) of the horizontal diameter and the vertical size of the electron beam passing hole of the guide inner electrode is greater than the horizontal / vertical ratio of the outer hole. The method according to claim 9 or 10, The center hole of the guide inner electrode is a color water pipe electron gun, characterized in that formed in the form of a keyhole that is a combination of a circle and a vertical rectangle. The method according to claim 9 or 10, An electron gun for a color receiver, characterized in that the center hole shape of the guide inner electrode is a vertical quadrangle. The method according to claim 9 or 10, Electron gun for a color water pipe, characterized in that the center hole shape of the guide inner electrode is a vertical oval. The method of claim 1, The shape of the center hole of the guide inner electrode has a vertical vertically larger than the horizontal electron gun for the color.

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