KR100492787B1 - Inline type electron gun for cpt - Google Patents

Abstract

The inline electron gun for color cathode ray tube according to the present invention comprises three independent electrodes to which Vf1 is applied, and two electrodes to which Vf2 is applied to the three independent electrodes to which Vf1 is applied. It reduces the convergence and minimizes the spherical aberration by reducing the distance of the through hole, that is, the pitch, by expanding the opening near the through hole of the central beam in the side beam through hole, and expanding the through hole of the main lens electrode. In this case, the resolution and convergence characteristics of the periphery of the screen are improved.

Description

Inline type electron gun for color cathode ray tube

The present invention relates to an inline electron gun for a color cathode ray tube, and more particularly, to an inline electron gun for a color cathode ray tube so as to improve resolution and convergence characteristics at the periphery of a screen while minimizing spherical aberration.

FIG. 1 is a horizontal cross-sectional view showing an example of a conventional inline electron gun. In the drawing, reference numeral 5 denotes a cathode which emits an electron beam arranged on a horizontal straight line, and a common control electrode 10 and a first screen electrode are disposed on the cathode. 20, an acceleration electrode 30, a second screen electrode 40, a first focusing electrode (static electrode) 50, and a second focusing electrode (dynamic electrode) 55 are provided. An electron gun employing a dynamic focus method consisting of a positive electrode 50 and a convergence cup 70, which form a lens. A quadrupole lens is formed in the electron gun to correct an electron beam spot in the periphery of the screen. The electrodes 50 and 55 are arranged.

FIG. 2 is a partial exploded view of the first focusing electrode 50 and the second focusing electrode 55 of FIG. 1.

In order to construct the quadrupole lens, the first focusing electrode 50 is provided with plate-like protrusions 50c and 50d on the electrode with the electron beam passing hole, and the bottom portion of the second focusing electrode 55 is bent inwardly. The plate-shaped protrusions 50c and 50d were inserted into both sides of the barrier 55a by an electrode on which one barrier 55a was formed, thereby forming a quadrupole lens.

The conventional inline electron gun as described above has a problem in that it is difficult to integrate these structures and is difficult to assemble in structure.

In addition, since a pair of barriers are common for three electron beams, a convergence defect occurs due to a voltage applied between the plate-shaped protrusion and the cylindrical electrode, thereby deteriorating the convergence characteristics.

In the case of adopting one quadrupole lens, when the dynamic voltage Vf2 is applied, there is a problem in that the vertical lens intensity is strongly applied, so that the edge beam of the horizontal axis beam of the spot becomes larger and the core beam becomes smaller. .

In order to solve this problem, the inline type electron gun for color cathode ray tube according to the present invention is composed of three independent electrodes to which Vf1 is applied, and two electrodes to which Vf2 is applied to face the three independent electrodes to which Vf1 is applied. Decreased convergence by biaxially reducing the distance, or pitch, of the three-electron beam pass-through hole of the static electrode, expanding the open part close to the through-hole of the center beam in the side-beam pass hole, and expanding the beam through hole open part of the main lens electrode Of course, the technical task of the present invention is to provide an inline electron gun for color cathode ray tubes with improved resolution and convergence characteristics around the screen while minimizing spherical aberration.

In order to achieve the above technical problem, the inline type electron gun for a color cathode ray tube of the present invention includes first, second, and third in which cathodes emitting an electron beam are arranged in a row and three electron beams pass through a through hole and are directed to a fluorescent surface. An inline electron gun for a color cathode ray tube comprising an electrode constituting a fourth electrode and a first quadrupole lens, an anode electrode and a convergence cup, comprising: three independent electrodes to which Vf1 is applied and three independent electrodes to which Vf1 is applied; It is composed of two electrodes which face each other and are applied with Vf2.

Hereinafter, an inline electron gun for a color cathode ray tube according to the present invention will be described in detail with reference to the drawings.

3 is a horizontal cross-sectional view of an inline electron gun in one embodiment of the present invention.

Cathodes 101, 102 and 103 for emitting an electron beam, a first electrode 110 as a control electrode, a screen electrode 120 as a second electrode, an acceleration electrode 130 and 132, and , The second screen electrode 140, the first focusing electrode 150, 152, the second focusing electrode 160, 162, the third focusing electrode 170, and the fourth focusing electrode ( 180, 182, 184, and the anode electrode is composed of (190), (192), (194) in the electron gun, the first and the third focusing electrode is applied to the voltage applied to the static focus electrode Vf1 In the second and fourth focusing electrodes, a voltage applied to the dynamic focus electrode is referred to as Vf2 (Parabola voltage), and an electrode to which Vf1 is applied and an electrode to which Vf2 is applied are opposed to each other.

Rim electrodes 184 and 190 are adopted to reduce the spherical aberration by increasing the main focusing lens.

FIG. 4 is an exploded view of the quadrupole electrodes 152 and 160 constituting the first quadrupole lens QP1 of the A-A 'plane of FIG. 1, and a circular beam passing hole ( 152a and 152b are formed and Vf2 is applied to the opposing dynamic electrode 160.

Unlike the third quadrupole of the C-C 'part, the effect of QP1 is to compensate for the intensity of the horizontal axis lens in the electronic lens to obtain a circular spot in the center of the screen.

In addition, in order to control the increase of the beam spot along the horizontal axis, the horizontal and vertical axis sizes of the electron beam passing holes 160a and 160b of the second focusing electrode should be adjusted. The upper and lower ends of the through-holes are characterized by having a long burring portion 160c and 160d inside the electrode.

FIG. 5 illustrates quadrupole electrodes 162, 170, and 170 constituting a second quadrupole lens QP2 and a third quadrupole lens QP3 on surfaces B-B ′ and C-C ′ of FIG. 1. 180 is configured.

The beam passing holes 170a and 170b of the third focusing electrode 170 are vertically larger than the horizontal axis in order to strengthen the quadrupole lens and obtain a long spot along the vertical axis when there is no deflection yoke magnetic field around the screen when Vf2 is applied. Set up your study.

The quadrupole lens formed by the second focusing electrode 162 and the third focusing electrode 170 on the B-B 'plane has a focus voltage between the center beam and the side beam by making the center beam stronger than the side beam. Minimized.

The opening of the dynamic electrode 180 facing the static electrode 170 has a shape of one large key hole, and has a burring portion from the vertical axis to the inside of the electrode to increase the longitudinal strength of the electron lens, thereby increasing the vertical axis. You can get the beam spot and lower the parabola voltage.

The third focusing electrode to which Vf1 is applied to remove the voltage difference of Vf2 between the center beam and the side beams because the quadrupole effect is weaker than that of the side beams R and B as keyholes. Out of the beam through holes 170a and 170b of 170, 170b through which the side beams pass is circular, and through holes 170a through which the central beam passes are long in the longitudinal axis, and the opening of the fourth focusing electrode. 180a is characterized in that the length d of the center burring portion 180c in the burring portion formed above and below is made longer than the side beam length of the burring portion 180d.

Table 1 shows the voltage improvement of Vf1 and Vf2 according to the test results applied to the color CRT of 17 kV or more with the inline electron gun constituting the electrode as described above.

6 shows a beam spot shape of the center of the screen when there is no screen center and a deflection yoke magnetic field.

FIG. 6A illustrates a conventional electron gun having a nucleus of a spot having a vertical axis V1 'larger than a horizontal axis H1' at a spot at the center of the screen, and a horizontal axis H2 'of a spot at the center of the screen. 10% less than H1 ').

In the case where the horizontal axis is reduced in this way, when the magnetic field of the deflection yoke is applied, the amount of distortion of the beam spot is increased to cause deterioration of focus.

6B shows that the horizontal axis H3 'of the beam spot can be obtained equal to or less than 5% of the vertical axis V3', and the horizontal axis beam H4 'of the screen periphery spot is equal to or greater than H3' and is increased by 5%. V4 ') is increased by 30% or more compared with the vertical spot V2' of the periphery of the screen of the conventional electron gun, thereby reducing the Vf2 voltage.

7 is a graph showing the convergence value according to the dynamic voltage Vf2 change, which is a conventional electron gun 300. The electron gun 320 according to the present invention changes the convergence change around the screen by about 0.005 to 0.01 mm at 100 V. The electron gun of was improved by more than 50% compared to the 0.02 ~ 0.04mm change.

In order to compensate for the convergence failure caused by the change in the concentration of the main lens formed between the anode electrode and the focusing electrode according to the modulation of the focus voltage Vf2, the distance, or pitch, of the three electron beam passing holes of the static electrode 170 is compensated for. 2) and the side beam through hole (170b) to enlarge the opening portion close to the through hole 170a of the center beam, and the beam through hole of the main lens electrode by expanding the opening as described above to reduce the convergence as well as spherical aberration Minimize

As described in detail above, the inline electron gun for a color cathode ray tube of the present invention has a color with an inline electron gun with improved resolution and convergence characteristics at the periphery of the screen by minimizing the problems of convergence deterioration and spherical aberration of the conventional electron gun. A cathode ray tube can be obtained.

1 is a horizontal cross-sectional view showing an example of a conventional inline electron gun,

2 is a partially exploded perspective view showing a quadrupole electrode forming a conventional quadrupole lens;

3 is a horizontal cross-sectional view showing an embodiment of an inline electron gun of the present invention;

4 is an exploded perspective view showing a quadrupole electrode showing an embodiment of the present invention;

5 is an exploded perspective view of a second quadrupole electrode according to one embodiment of FIG. 3;

6A and 6B are diagrams showing a comparison between the beam spot of the conventional electron gun and the spot of the present invention, respectively;

Figure 7 is a graph showing the change in convergence according to the voltage Vf2 change of the electron gun of the present invention.

Explanation of symbols on the main parts of the drawings

101,102,103 .... cathode 110 .... first electrode

120 .... second electrode 130 .... acceleration electrode

140 ... second screen electrode 150 ... first focusing electrode

160 .... the second focused electrode 170 .... the third focused electrode

180 .... fourth focusing electrode 184,190 .... rim electrode

Claims (8)

Three cathodes emitting electron beams are arranged in a row, and the first, second, third, and fourth electrodes through which the electron beams pass, the electrode constituting the quadrupole lens, the anode electrode and the convergence cup In the inline electron gun for cathode ray tube, A plurality of quadrupole lenses comprising a plurality of static electrodes and a dynamic electrode, wherein a static electrode to which Vf1 is applied and a dynamic electrode to which Vf2 is applied are assembled to face each other. The method of claim 1, wherein in constructing the first quadrupole lens, the three electron beam through holes of the static electrode are formed in a circular shape, and the central through holes of the electron beam through holes of the dynamic electrode opposite to each other are formed in a horizontal keyhole shape. An inline electron gun for a color cathode ray tube, wherein the side beam through hole is formed in a rectangular shape. 3. The in-line electron gun for color cathode ray tube according to claim 2, wherein a burring portion is formed in the upper and lower ends of the dynamic electron beam passing hole inwardly of the electrode. The method of claim 1, wherein the center beam through hole in the electron beam through hole of the electrode to which the static voltage is applied in the electrode constituting the second quadrupole lens is a keyhole shape of a shape extending vertically rather than horizontal, An inline electron gun for color cathode ray tubes, characterized in that the ball is formed in a circular shape. The in-line electron gun for color cathode ray tube according to claim 1, wherein the non-passing hole of the dynamic electrode facing the static electrode is composed of a single key hole through which three beams pass in common. The electron gun for a color cathode ray tube according to claim 5, wherein a burring portion is provided in the upper and lower ends of the electron beam passing hole of the key hole inwardly of the electrode. The method of claim 6, wherein a predetermined distance from the center of the burring portion is a central beam through hole, both sides outside the predetermined distance is a side beam through hole, and the length of the central beam through hole burring portion is greater than the length of the burring portion of the side beam through hole. Inline electron gun for color cathode ray tube. 7. The inline electron gun for color cathode ray tube according to claim 6, wherein a width of the central beam through hole burring portion is larger than a width of a side beam through hole.

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