KR20010054761A - Electrode structure of electron gun for cathode ray tube - Google Patents

Abstract

PURPOSE: An electrode structure of an electron gun for a CRT is provided to be capable of enhancing the uniformity of an electron beam by forming three electrode to have shapes different from each other to laterally lengthen the electron beam, and of minimizing the distortion of the electron beam when the electron beam is deflected toward the periphery of a screen. CONSTITUTION: The electrode structure comprises first to sixth electrodes for forming a lens focusing and accelerating an electron beam. The first electrode(103) has circular holes(401) through which the electron beam passes. A rectangular slot for varying the focusing force of the electron beam is formed on one side of the second electrode, and a square hole for the passage of the electron beam is formed in the center of the rectangular slot. A long hole of a key shape for the passage of the electron beam is formed in the third electrode.

Description

Electrode structure of electron gun for cathode ray tube

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrode structure of an electron gun for cathode ray tube, and more particularly to an electrode structure of an electron gun for cathode ray tube that can improve the focusing of an electron beam by changing the shape of a slot of an electrode.

1 is a schematic diagram of a typical cathode ray tube.

Referring to FIG. 1, a cathode ray tube generally includes a stem pin 101 to which a voltage is applied, a cathode 102 for emitting electrons, and a lens for controlling / accelerating electrons emitted from the cathode. The first electrode 103, the second electrode 104, the third electrode 105, the fourth electrode 106, the fifth electrode 107, the sixth electrode 108, and the sixth electrode 108. Shield cup 109 for fixing the electron gun to the neck of the tube 109 while electrically connecting the electron gun and the tube 109 to the upper portion of the electron beam formed by the electrons emitted from the electron gun ( A deflection yoke 110 for evenly deflecting the beam 112 to the entire screen 113, and a shadow mask for selecting a color at a predetermined distance from the screen 113 It consists of 112.

The operation of the cathode ray tube having the above configuration will be briefly described.

First, when a voltage is supplied to the stem pin 101, heat is applied to the cathode 102, and electrons are emitted from the cathode 102 to which the heat is applied. The emitted electrons are controlled by the first electrode 103 and the second electrode 104, and are partially focused / accelerated by the third electrode 105 and the fourth electrode 106, and the electrons continue to be focused ( The main focusing / acceleration is achieved by the fifth electrode 107, which is a lens forming electrode called the focus electrode, and the sixth electrode 108, which is an anode electrode. The electron beam 111 formed by the focused / accelerated electrons is deflected by the deflection yoke 110 and evenly spread on the entire screen 113. The electron beam 111 passes through the shadow mask 112 provided in front of the screen 113 and collides with the phosphor applied to the screen 113 to emit light.

At this time, the electron beam 111 is deflected to the entire screen 113 by the non-uniform deflection magnetic field of the deflection yoke 110, the non-uniform deflection magnetic field has a strong focusing force in the vertical direction and focusing force in the horizontal direction This weakness causes a halo phenomenon of the electron beam 111 in which the electron beam 111 is convex in the vertical direction on the screen 113.

Here, the non-uniform magnetic field of the deflection yoke 110 will be briefly described with reference to FIGS. 2A and 2B.

2A illustrates a non-uniform magnetic field in the vertical direction of the deflection yoke 110 and FIG. 2B illustrates a non-uniform magnetic field in the horizontal direction.

2A and 2B, the non-uniform magnetic field of the deflection yoke 110 includes a dipole component and a quadrupole component, and the dipole component serves to deflect the electron beam 111 in a horizontal or vertical direction. The four-pole component serves to focus the electron beam 111 in the vertical direction and diverge in the horizontal direction. Therefore, since the electron beam 111 is focused at a shorter distance in the vertical direction than in the horizontal direction, the core portion of the core 201 having a high density of electrons and the portion of the halo 202 having a low density of electrons are formed on the screen 113. The halo 202 phenomenon occurs in which the electron beam 111 is convexly raised in the vertical direction. The halo 202 phenomenon lowers the focusing force of the electron beam 111 around the screen 113 and degrades the image quality.

In the non-uniform magnetic field, a four-pole component that focuses the electron beam 111 in the vertical direction and diverges in the horizontal direction is called a DY lens.

In order to solve the problem causing the halo 202 phenomenon, a method of canceling the quadrupole component generated by a non-uniform magnetic field by inserting a quadrupole lens that generates a quadrupole component corresponding to the electron gun is employed. This quadrupole lens focuses the electron beam 111 in the horizontal direction and diverges the electron beam 111 in the vertical direction. Therefore, it is possible to compensate for the difference in focusing distance of the electron beam 111 focused in the vertical direction and diverged in the horizontal direction by the DY lens.

However, the method of compensating the focusing distance of the electron beam 111 by the quadrupole lens as described above weakens the focusing effect of the main lens formed on the fifth electrode 107 to further reduce the electron beam 113 at the periphery of the screen. There is a problem in that the moiré phenomenon in which the ripples appear to be horizontal.

Thus, as a method for improving the above problem, a method of horizontally lengthening the electron beam 111 at the three pole portions of the first electrode 103, the second electrode 105, and the third electrode 105 is employed. .

3 is a plan view of an electrode of a conventional electron gun for cathode ray tubes.

Referring to FIG. 3, the electrode structure of the conventional cathode ray tube electron gun includes a rectangular slot 301 having a horizontal shape for differently focusing the electron beam 111 on one side of the second electrode 104. A hole 302 is formed in the center of the slot 301 for the electron beam 111 to pass through.

In the electrode as described above, a slot 301 having a rectangular shape is formed around the hole through which the electron beam 111 passes, and the thickness of the electrode around the hole 302 is different. That is, the thickness in the lateral direction is thinner than the thickness in the longitudinal direction. Therefore, the focusing force in the lateral direction of the electron beam 111 is weaker than the focusing force in the longitudinal direction, so that the electron beam 111 having passed through the electrode with the slot 301 is lateralized.

When the electron beam 111 is thus horizontally focused through the main lens of the fifth electrode 107 and the DY lens of the deflection yoke 110 and focused on the screen 113, the focusing distance is shortened in the horizontal direction and is vertical. In the direction, the focal length can be made long to compensate for the difference d of the focal length by the DY lens.

As described above, in order to compensate for the difference in focusing distance in the horizontal direction and the vertical direction by the DY lens, a method of forming a quadrupole lens and a slot 301 in the second electrode 104 are formed to form an electron beam 111 at the three poles. However, the method of horizontally increasing the size of the screen) is employed, but it is not sufficient to compensate for the halo phenomenon caused by the enlargement and flatness of the screen.

The present invention is to improve the above problems, by forming the electrode shape of the three poles differently to further lengthen the electron beam in the three poles to evenly focus the electron beam in the entire screen, the electron beam when the electron beam is deflected to the periphery of the screen An object of the present invention is to provide an electrode structure of an electron gun for a cathode ray tube that can minimize distortion.

1 is a schematic diagram of a typical cathode ray tube.

2A shows the non-uniform magnetic field of the deflection yoke in the vertical direction.

2b shows a non-uniform magnetic field of the deflection yoke in the horizontal direction.

3 is a plan view of an electrode of a conventional electron gun for cathode ray tubes.

4 is a plan view of a first electrode of an electron gun for a cathode ray tube according to the present invention;

5 is a plan view of a second electrode of an electron gun for a cathode ray tube according to the present invention;

6 is a plan view of a third electrode of an electron gun for a cathode ray tube according to the present invention;

<Explanation of symbols for the main parts of the drawings>

101 ... Stem 102 ... Cathode

103 ... first electrode 104 ... second electrode

105 ... third electrode 106 ... fourth electrode

107 ... fifth electrode 107a ... first focused electrode of fifth electrode

107b ... second focusing electrode of the fifth electrode 108 ... sixth electrode

109 ... shield cup 110 ... deflection yoke

111 ... electron beam 112 ... shadow mask

113 ... screen

201 ... Core 202 ... Halo

301, 501 ... slot

302, 401, 502, 601 ... hole

In order to achieve the above object, the electrode structure of the cathode ray tube electron gun according to the present invention, the electrode structure of the cathode ray tube electron gun comprising a first electrode to a sixth electrode for forming a lens to focus and accelerate the electron beam, A first electrode having a circular hole for passing the electron beam, a slot having a rectangular shape for forming a different focusing force of the electron beam on one side and a square hole for passing the electron beam in the center of the slot is formed And a third electrode having an elongated keyhole-shaped hole through which the electron beam passes.

Here, the circular hole of the first electrode has a diameter of 0.45 ~ 0.55mm, the square hole of the second electrode has a length of 0.45 ~ 0.55mm of one side, the slot has a horizontal length of 0.7 ~ 0.9mm, The vertical length is 0.5 to 0.7 mm, the depth is 0.19 to 0.23 mm, the hole of the third electrode is preferably 1.45 to 1.55 mm in diameter, the vertical length is 2.9 to .3.1.

As described above, the present invention minimizes the difference between the horizontal focusing distance and the vertical focusing distance of the electron beam on the screen by lateralizing the electron beam emitted from the electron gun, thereby enhancing the focusing power of the electron beam at the periphery of the screen, Can be realized.

Hereinafter, an electrode structure of an electron gun for a cathode ray tube according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

The electrode structure of the electron gun for cathode ray tube of the present invention, as shown in Figure 1, the first electrode 103 to sixth electrode 108 for forming a lens for focusing / accelerating the electron beam emitted from the cathode 102 In the electrode structure of a cathode ray tube electron gun including, as shown in Figs. 4, 5 and 6, the structures of the first electrode 103, the second electrode 104, and the third electrode 105 are the same as those of the conventional one. different.

That is, referring to FIGS. 4, 5 and 6, the electrode structure of the electron beam gun for a cathode ray tube according to the present invention includes a first electrode 103 having a circular hole 401 for the electron beam 111 to pass through. A rectangular slot 501 of a horizontal shape is formed on the side to change the focusing force of the electron beam 111, and a square hole 502 is formed in the center of the slot 501 for the electron beam 111 to pass through. And a third electrode 105 having an elongated key hole shape 601 through which the second electrode 104 and the electron beam 111 pass.

Here, the first electrode 103 minimizes the size of the electron beam 111 emitted by making the diameter of the hole 401 0.45 to 0.55 mm. In addition, the second electrode 104 has a square hole 502 through which the electron beam 111 passes in order to horizontally lengthen the electron beam 111, and the length of one side thereof is 0.45 to 0.55 mm, and the horizontal length is around 0.7 to 0.5 mm. A slot 501 having a length of 0.9 mm, a length of 0.5 to 0.7 mm, and a depth of 0.19 to 0.23 mm is formed. In addition, the key hole-shaped hole 601 of the third electrode 105 preferably has a diameter of 1.45 to 1.55 mm and a vertical length of 2.9 to 3.1 mm.

The distance between the first electrode 103 and the second electrode 104 is 0.13 mm, and the distance between the second electrode 104 and the third electrode 105 is 1.02 mm. Can have an error of ± 0.05mm)

On the other hand, the aspect ratio of the electron beam 111 before the electron beam 111 is incident on the main lens affects the difference in the focusing speed in the center portion and the peripheral portion of the screen 113. When the aspect ratio is horizontal to vertical ratio of 1.7: 1, the difference in focal velocity is the smallest. In addition, the aspect ratio of the electron beam increases as the distance between each electrode approaches, but the withstand voltage decreases accordingly.

Therefore, in order to achieve the optimal lengthening of the electron beam 111, it is preferable to arrange the electrode having the above-mentioned distance at the above distance.

When the electrode is configured as described above, the size of the electron beam 111 emitted from the first electrode 103 is optimized, and the second electrode 104 has a horizontal direction around the hole 501 through which the electron beam 111 passes. Due to the difference in thickness of the electrodes in the vertical direction, the focusing action is changed. That is, since the slot 501 of the second electrode 104 is in the transverse direction, the thickness of the second electrode 104 is thicker in the longitudinal direction than in the transverse direction. Since the focusing is less, the electron beam 111 is horizontalized. In addition, the electron beam 113 diverges while passing through the third electrode 105. Since the distance between the electrodes in the transverse direction is closer than the longitudinal direction of the third electrode, the electron beam 113 diverges more in the horizontal direction than in the vertical direction. The electron beam 111, which has been transversed through the electrode 104, is further transversed in the third electrode 105.

Therefore, as described above, the electron beam 111 is horizontally lengthened at the triode before the electron beam 111 is incident on the main lens, thereby compensating for the difference between the horizontal focusing distance and the vertical focusing distance by the DY lens.

As described above, the electrode structure of the electron gun for cathode ray tube according to the present invention, by having the electrode as described above, the horizontal focusing distance and the vertical focusing distance in the screen generated by the DY lens by horizontally lengthening the electron beam in the triode And the focusing power of the electron beam in the center of the screen and the periphery of the screen.

In addition, by enhancing the focusing force of the electron beam as described above, there is an advantage that the screen can be enlarged and high resolution can be realized.

Claims (5)

In the electrode structure of the electron gun for cathode ray tube comprising a first electrode to a sixth electrode for forming a lens to focus and accelerate the electron beam, A first electrode having a circular hole through which an electron beam passes; A second electrode having a horizontal slot formed on one side thereof to have a different focusing force of the electron beam, and a square hole formed therein for passing the electron beam in the center of the slot; and An electrode structure for cathode ray tubes comprising a third electrode having an elongated keyhole shape hole through which an electron beam passes. The method of claim 1, The hole of the first electrode is the electrode structure of the electron gun for cathode ray tube, characterized in that the diameter of 0.45 ~ 0.55mm. The method according to claim 1 or 2, The square hole of the second electrode has a length of 0.45 to 0.55 mm on one side, and the slot has a horizontal length of 0.7 to 0.9 mm, a vertical length of 0.5 to 0.7 mm, and a depth of 0.19 to 0.23 mm. An electrode structure of an electron gun for cathode ray tubes. The method according to claim 1 or 2, The hole of the third electrode has a diameter of 1.45 ~ 1.55mm, the vertical length of the electrode structure of the electron gun for cathode ray tube, characterized in that 2.9 ~ 3.1mm. The method of claim 3, wherein The hole of the third electrode has a diameter of 1.45 ~ 1.55mm, the vertical length of the electrode structure of the electron gun for cathode ray tube, characterized in that 2.9 ~ 3.1mm.