KR20030037210A - Screen electrode for CPT, electron gun and CPT therewith - Google Patents

Abstract

PURPOSE: An electron gun for a color cathode ray tube is provided to be capable of adjusting the convergence between electron beams and correcting the coma aberration occurred in a main lens by controlling the direction of the electron beams. CONSTITUTION: A screen electrode(70) has three slots(71,72,73) formed in a line on an incident or an emergency surface of an electron beam and electron passing holes(75,76,77) formed in the contours of the slots. The slot arranged in the middle side of the slots is longer than the other slots in the length of the in-line direction. The center of the slot arranged in the middle side corresponds to the center of its electron beam passing hole. The centers of the other slots are deflected from the centers of their electron beam passing holes to one way of the in-line respectively.

Description

Screen electrode of electron gun for color cathode ray tube, electron gun and color cathode ray tube provided with it {Screen electrode for CPT, electron gun and CPT therewith}

The present invention relates to a screen electrode of an electron gun for a color cathode ray tube, an electron gun provided with the same and a color cathode ray tube, and more particularly, a screen electrode of an electron gun for a color cathode ray tube having an improved slot shape formed thereon, and an electron gun provided with the same. And a color cathode ray tube.

Typically, the color cathode ray tube is equipped with an electron gun. The electron beam incident from the electron gun is deflected to enter the fluorescent film formed on the inner surface of the panel to excite the phosphor, thereby displaying a predetermined image. The electron gun is provided with a cathode, a control electrode, a screen electrode, and a focus electrode.

1 to 4 are views of the color cathode ray tube disclosed in US Pat. No. 4,523,123, and an electron gun and an electrode provided therein.

1 is a schematic cross sectional view of a conventional colored cathode ray tube.

Referring to the drawings, the color cathode ray tube 10 includes a bulb 11 composed of a funnel 16 and a panel 12, a shadow mask 24 provided inside the panel 11, and the funnel 16. The deflection yoke 30 provided in the outer side and the electron gun 16 provided in the neck 14 of the funnel 16 are provided. The fluorescent film 22 is formed in the inner surface of the panel 11.

In the color cathode ray tube 10 having the above-described configuration, the electron beam 28 incident from the electron gun 26 is deflected by the deflection yoke 30 to the fluorescent film 22 through the through hole formed in the shadow mask 24. Will be reached. The electron beam reaching the fluorescent film 22 can display an image by exciting the phosphor, and the observer can recognize the display screen by observing the display screen 18.

Shown in Figure 2 is a schematic cross-sectional view of a conventional electron gun provided in the color cathode ray tube.

Referring to the drawings, the electron gun is disposed in order in front of the cathode assembly 34, the cathode assembly 34, the control electrode 36, the screen electrode 38, the first acceleration and the focus electrode ( 40, a second acceleration, and a focus electrode 42. A second cup and a shield cup 48 are disposed in front of the focus electrode 42, and the electrodes and the shield cups 48 are supported by each other by being fused to the bead glass support 32. As is known, the electrodes are labeled G1, G2, G3 and G4, respectively.

The control electrode 36 has an electron beam passing hole 56 through which an electron beam incident from each cathode assembly 34 corresponding to red, green, and blue passes. In addition, an electron beam through hole 58 corresponding to the screen electrode 38 is formed. The first acceleration and focus electrode 40 is formed by welding two cup members 44 and 46 to each other, and electron beam through holes 54 and 52 are formed in each of them. Similarly, the electron beam passage hole 50 is also formed in the second acceleration and focus electrode 42.

Meanwhile, slots 60, 62, and 64 are formed in the screen electrode 38 corresponding to each of the electron beam through holes 58. The slots 60, 62, 64 are formed on the exit side of the electron beam, which is the upper surface of the screen electrode 38 as seen in the figure.

3 is a plan view of the screen electrode of FIG. 2.

Referring to the drawings, slots 60, 62, and 64 are formed on the surface of the screen electrode 38 in-line, and the electron beam through hole 58 is formed inside the boundary line formed by the contour of the slots. It can be seen that is formed.

As can be seen at a glance in the drawings, the size of the three slots (60, 62, 64) are all the same. That is, the relationship of L1 + L2 = 2 x L3 is established. In addition, the central electron beam through hole 58 is disposed at the exact center of the corresponding slot 62. That is, the distance between the center of the electron beam passing hole 58 and the left and right sides of the slot is the same as L3. On the contrary, it can be seen that the centers of the respective slots 60 and 64 are eccentric inward with respect to the centers of the respective electron beam through holes 58. That is, the distance between the center of the electron beam passing hole 58 disposed on the right side and the rightmost side of the slot 60 is L1, whereas the distance between the center of the electron beam passing hole 58 and the leftmost side of the slot 60 is L2. On the contrary, the distance between the center of the electron beam passing hole 58 disposed on the left side and the leftmost side of the slot 64 is L1, while the distance to the rightmost side of the slot 64 is L2. Therefore, L1 ≠ L2 ≠ L3.

Forming a slot on the exit side of the screen electrode and locating the slot eccentrically with respect to the electron beam through hole generates a change in the equipotential surface without directly biasing the electron beam through holes, thereby converting the path of the electron beam. It is for. In addition to the above-described method for converting the path of the electron beam in the screen electrode, there may be a method of differentially forming the slot or selectively forming the slot. In addition, a method of eccentricizing the electron beam passing hole itself can be applied.

In the electron gun described with reference to FIGS. 1 to 3, when embossing is formed on the surface of the screen electrode 38, the embossing portion and the slots 60 and 64 cause mutual interference. That is, there is a case where an annular embossing is formed on the surface of the screen electrode 38 around the slots 60 and 64. In this case, the slots 60 and 64 and the embossing interfere with each other, thereby making it difficult to design. It is. In addition, when the electron beam through-hole itself is eccentric, an inspection process must be added in the manufacturing process in order to improve the alignment characteristics with the electron beam through-holes formed in the other electrodes, and there is a problem in that scattering management is also difficult.

The present invention has been made to solve the above problems, and an object of the present invention is to provide an improved screen electrode, an electron gun and a color cathode ray tube having the same.

Another object of the present invention is to provide a screen electrode having a different sized slot, an electron gun and a color cathode ray tube having the same.

1 is a schematic cross-sectional view of a colored cathode ray tube according to the prior art;

FIG. 2 is a schematic cross-sectional view of an electron gun provided in the color cathode ray tube of FIG. 1. FIG.

3 is a plan view of the screen electrode provided in FIG.

4 is a plan view of a first embodiment of a screen electrode according to the invention;

FIG. 5 is a cross-sectional view of the screen electrode shown in FIG. 4. FIG.

6 is a plan view of a second embodiment of a screen electrode according to the invention;

FIG. 7 is a cross-sectional view of the screen electrode shown in FIG. 6. FIG.

8 is a plan view of a third embodiment of a screen electrode according to the invention;

9 is a sectional view of the screen electrode shown in FIG. 8;

<Brief Description of Major Codes in Drawings>

12.Panel 14.Neck

16. Funnel 18. Display Screen

22. Fluorescent film 26. Electron gun

34. Cathode Assembly 38. Screen Electrode

71.72.73. Slot 75.76.77. Electron beam through hole

In order to achieve the above object, according to the present invention, three slots which are provided in the electron gun for the color cathode ray tube, formed in-line on one surface of the incident side or the exit side of the electron beam, and each of the slots A screen electrode having an electron beam through hole formed in an outline, wherein the inline direction length of the slot disposed at the center of the slots is larger than the horizontal inline direction length of the other slot disposed at the outside, and the center of the slot disposed at the center thereof. Wherein is formed to coincide with the center of the electron beam through hole, the center of the slot disposed in the outer space is provided with a screen electrode which is formed in a state in which the state in the direction inclined in one direction inline from the center of the electron beam through hole.

According to one feature of the invention, the center of the slot disposed in the outer space is formed in a state in which the deviation in the inner direction of the in-line on the departure from the center of the electron beam through hole.

According to another feature of the invention, the center of the slot disposed in the outer space is formed in a state in which the deviation from the center of the electron beam through-hole in the outward direction in the inclined state.

According to another feature of the invention, the annular embossing is formed on the outside of each slot.

According to the present invention, there is also provided a cathode, a control electrode and a screen electrode, which form an anterior triode, and at least one focus electrode disposed in front of the screen electrode, the electron electrode for color cathode ray tube, wherein the screen electrode of the electron beam In-line direction of three slots formed in-line on one surface of the incidence side or the outgoing side, and an electron beam through hole formed in the contour of each slot, the slot disposed at the center of the slots The length is larger than the in-line length of the other slots disposed at the outer side, and the center of the slot disposed at the center is formed to coincide with the center of the electron beam passing hole, while the center of the slot disposed at the outer side is formed of the electron beam passing hole. Provided is an electron gun for a color cathode ray tube, characterized in that formed in a state shifted from the center in one direction on the inline All.

According to the present invention, there is also a bulb comprising a panel and a funnel formed on the inner surface of the fluorescent film, a shadow mask provided on the inside of the panel, an electron gun provided on the neck of the funnel and provided with a screen electrode, and outside the funnel In a color cathode ray tube having a deflection yoke provided, the screen electrode includes three slots formed in-line on one surface of an incident side or an exit side of the electron beam, and an electron beam formed in the contour of each slot. And a through hole, wherein the inline direction length of the slot disposed at the center of the slots is larger than the inline direction length of the other slot disposed at the outer side, and the center of the slot disposed at the center is coincident with the center of the electron beam through hole. On the other hand, the center of the slot disposed at the outer side is shifted in one direction in-line at the center of each electron beam through hole. The color cathode ray tube characterized in that the formation is provided.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The electron gun provided with the screen electrode and the color cathode ray tube according to the present invention are basically the same as those described with reference to FIGS. 1 and 2. In more detail, as shown in FIG. 1, the color cathode ray tube includes a bulb 11 including a panel 12 and a funnel 16 having a fluorescent film 22 formed on an inner surface thereof, and the panel 12. ), A shadow mask (24) provided on the inner side, an electron gun (26) provided on the neck (14) of the funnel (16), and a deflection yoke (30) provided on the outside of the funnel (15). Meanwhile, as shown in FIG. 2, the electron gun includes cathode assemblies 34, a plate-shaped control electrode 36, a screen electrode 38, and the screen electrode sequentially disposed in front of the cathode assembly 34. A first acceleration and focus electrode 40 and a second acceleration and focus electrode 42 disposed in front of 38 and formed of at least one cup-shaped electrode.

4 shows a screen electrode of the electron gun for a color cathode ray tube according to the present invention as a plan view, which is compared with FIG. 3 described above.

In the figure, D1, D2, and D3 indicate the length in the inline direction from the center of each electron beam through hole to the leftmost or rightmost side of each slot. The total horizontal length of the slot 72 disposed at the center may be expressed as 2 × D3. On the contrary, in-line lengths of the left and right slots 71 and 73 may be represented by D1 + D2, and have a relationship of D1 ≠ D2. That is, the left slot 71 and the right slot 73 are shifted in the inline direction inward from the center of the respective electron beam through holes 75 and 77. Also, unlike the screen electrode described with reference to FIG. 3, since the inline direction size of the center slot 72 and the inline direction size of the peripheral slots 71 and 73 are different from each other, a relationship of 2 × D3 ≠ D1 + D2 is obtained. Have

5 is an enlarged cross section of the screen electrode illustrated in FIG. 4.

Referring to the drawings, slots 71, 72, and 73 are formed to a predetermined depth in the upper plane of the screen electrode 70, and electron beam through holes 75, 76, and 77 penetrate through the thickness of the screen electrode 70. I can see that. In addition, it can be seen that the respective slots 71 and 73 are biased.

6 shows a screen electrode according to another embodiment of the present invention as a plan view.

Referring to the drawings, slots 81, 82, and 83 are formed on the surface of the screen electrode 80, and electron beam through holes 85, 86, and 87 are formed inside the boundary line formed by the contours of the slots. have.

As described above, the size of the center beam through hole slot 82 and the size of the two slots 81 and 83 in the peripheral beam through hole are formed different from each other. The size of the slot 82 located at the center of the three slots extends longer in the inline direction than the other two slots 81 and 83 around. In addition, the electron beam passing hole 86 is disposed in the center of the slot 82. On the contrary, the slots 81 and 83 formed at the left and right sides are shorter in the inline direction than the slots 86 at the center, and the left slot 81 and the right slot 83 have respective electron beam passing holes 85. It can be seen that, in the outward direction on the inline from the center of the (87).

As defined above, the overall inline direction length of the center slot 82 can be expressed as 2 x D3. In contrast, the lengths of the in-line directions of the slots 81 and 83 on the left and right sides may be represented by D1 + D2, and have a relationship of D1 ≠ D2. That is, the left slot 81 and the right slot 83 are shifted in the inline outward direction from the center of the respective electron beam through holes 85 and 87. In addition, since the size of the in-line direction of the center slot 82 and the size of the in-line direction of the peripheral slots 81 and 83 are different, they have a relationship of 2 x D3? D1 + D2.

7 is an enlarged cross-sectional view of the screen electrode shown in FIG. 5.

Referring to the drawings, slots 81, 82, and 83 are formed to a predetermined depth in the upper plane of the screen electrode 80, and electron beam through holes 85, 86, and 87 penetrate through the thickness of the screen electrode 80. I can see that. Further, each of the peripheral slots 81 and 83 is biased in the outward direction on the inline.

In the electron gun provided with the screen electrode having the configuration of the slot as described above, the inclination occurs in the equipotential surface due to the difference in the width of the left and right sides of the slot on the incidence side or the outgoing side of the screen electrode, and thus the incident direction of the electron beam. Can be adjusted. Therefore, by adjusting the size and the direction of deflection by adapting to each situation, it is possible to obtain an appropriate amount of deflection of the electron beam.

9 is a plan view showing an example in which the screen electrode according to the present invention is applied together with the annular embossing.

Referring to the drawings, slots 91, 92, and 93 are formed on the surface of the screen electrode 90, and electron beam through holes 95, 96, and 97 are formed inside the boundary line formed as the outline of the slots. have. The peripheral slots 91 and 93 are shorter in the inline direction than the central slot 92 (D1 + D2 <2 × D3), and the left slot 91 and the right slot 93 are respectively It is shifted outwardly in the inline direction from the center of the electron beam through holes 95 and 97. On the other hand, an annular embossing 98 is formed outside the slots, and these embossings 98 do not interfere with the slots 91 and 93. This is because the inline directional length of the slots 91 and 93 is shorter than the slot 92.

9 is a cross-sectional view of the screen electrode shown in FIG. 8, and the shape of the embossing 98 can be understood from FIG. 9.

The screen electrode provided in the electron gun for a color cathode ray tube according to the present invention is formed so that each slot of the periphery is shifted to the center of each electron beam through hole, and each slot of the periphery is formed shorter than the slot in the center, the equipotential formed between the electrodes The faces may have a slope in a certain direction, which may act on the moving electron beam to move the direction of the electron beam. By adjusting the direction of the electron beam in this way, the convergence between the electron beams can be adjusted, and coma aberration generated in the main lens can be corrected. In addition, even when forming the annular embossing on the screen electrode can be applied without difficulty, it is possible to remove the eccentricity between the electron beam through-holes to improve the convenience of the manufacturing process and reduce the quality distribution due to the eccentricity.

Although the present invention has been described with reference to the embodiments illustrated in the drawings, these are merely exemplary and those skilled in the art will understand that various modifications and equivalent other embodiments are possible therefrom. Therefore, the present invention should only be limited by the appended claims.

Claims (3)

Cathodes forming an anterior triode, A control electrode disposed in front of the cathode, It is disposed in front of the control electrode, and provided with three slots formed in-line on one surface of the incident side or the exit side of the electron beam, and the electron beam through hole formed in the contour of each slot, The inline direction length of the slot disposed at the center of the slots is larger than the inline direction length of the other slot disposed at the outer side, and the center of the slot formed at the center is formed to coincide with the center of the electron beam through hole, whereas the outer The center of the slot formed in the screen electrode is formed in a state in which in the direction inclined in one direction on the in-line from the center of each electron beam through hole; And, An electron gun for a color cathode ray tube comprising at least one focus electrode disposed in front of the screen electrode. The method of claim 1, The center of the slot formed on the outer side is formed in a state in which the inclined in the in-line direction in the center of each electron beam through hole formed in the electron gun for color cathode ray tube. The method of claim 1, The center of the slot formed on the outer side is formed in the state of the electron beam through-holes in the state inclined in the outward direction in the inward direction, characterized in that the electron gun for a color cathode ray tube.