JPH1074464A - Electrode component of color cathode-ray tube electron gun and manufacture thereof, anode electrode, focus electrode, and intermediate electrode of color cathode-ray tube electron gun, and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the electrode components of a color cathode-ray tube electron gun in which constituting number of the electrode components of the electron gun constituting a main focus lens such as a focus electrode and an anode electrode can be reduced, and manufacturing and the incorporation into the electron gun can be conducted with high precision. SOLUTION: An electrode component 10 is composed of a flange portion 12, cylindrical first side wall 13 extending from the flange portion 12, cylindrical second side wall 15 folded inward from the end portion of the first side wall 13 and extending in parallel to the first side wall, and a bottom face portion 16 which is formed at the end portion of the second side wall 15 and in which electrode beam passing holes 17 are provided. The flange portion 12, the first side wall 13, the second side wall 15, and the bottom face portion 16 are integrally formed from a metal plate 11 by deep drawing, and the length L2 of the first side wall 13 is shorter than the length L<1> of the second side wall 15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an electrode part of an electron gun for a color cathode ray tube and a method of manufacturing the same, an anode electrode and a focus electrode of an electron gun for a color cathode ray tube, an intermediate electrode, and a method of manufacturing the same.

[0002]

2. Description of the Related Art In recent years, the demand for resolution of a color cathode ray tube has been increasing more and more. One of the major factors that determine the resolution is the electron beam spot diameter on the phosphor screen, and it is necessary to reduce the electron beam spot diameter in order to obtain high resolution. Generally, the electron beam spot diameter S at the center of the phosphor screen surface can be obtained by the following equation (1).

[0003]

[Number 1] _{S = {(M × d c} + M × C s × θ 3/2) 2 + Δd rep 2} 1/2 (1)

[0004] Here, M is the image magnification of the electron beam,
d _c is the virtual object point diameter of the electron beam, C _s is the spherical aberration coefficient of the main focus lens, θ is the divergence angle of the electron beam, and Δd _rep is the increase in diameter due to the repulsive force of the electrons ( Repulsion).

[0005] To reduce the electron beam spot diameter S, the spherical aberration coefficient C _s of the main focus lens of the electron gun is required.
It is effective to reduce the diameter of the main focus lens. One way to achieve this is to increase the aperture of the main focus lens. Then, in order to enlarge the aperture of the main focus lens, an electric field sharing type large aperture electron gun, and furthermore,
A large-diameter electron gun in which an electric field extension method is superimposed on an electric field sharing method is employed.

FIG. 3 is a conceptual diagram of a conventional bi-potential type electron gun. This electron gun has three in-line cathodes KR, KG, KB, a first electrode (control electrode) 1, a second electrode (acceleration electrode) 2, a third electrode 3, a fourth electrode 4, and a focus. It comprises an electrode (fifth electrode) 5, an anode electrode (sixth electrode) 6, and a shield cup 7. The focus electrode 5 and the anode electrode 6 constitute a main focus lens. Focus voltage V _f of 6kV~10kV from the stem (not shown) is applied to the focus electrode 5. On the other hand, for example, 27 kV from the anode button (not shown) is applied to the anode electrode 6.
The anode voltage V _a of the high pressure is applied to the.

In the electron gun of the electric field sharing type, as shown in a schematic sectional view of FIG. 9A, the focus electrode 5 is composed of the front lens component 101, the drift space component 1
2, a flat plate press part 103 having three electron beam passage holes, and a burring member 104 having one oval burring part. In addition, the anode electrode 6
Is composed of a drift space component 102, a flat plate press component 103 having three electron beam passage holes, and a burring member 104 having one oblong burring portion.
The oval burring portion is formed on the entire periphery of the tip of the burring member 104. Here, the components for constituting the main focus lens are the flat plate press part 103 and the burring member 104. In addition, a focus electrode (fifth electrode) and an anode electrode (sixth electrode) having a structure in which the flat pressed part 103 enters the burring member 104 are also known. FIGS. 9B and 9C are schematic plan views of the burring member 104 and the flat plate pressing part 103 constituting the focus electrode 5 and the anode electrode 6 viewed from the arrow BB in FIG. 9A. The figure is shown.

The principle that the three electron beams become a spot having a round shape on the phosphor screen surface of the color cathode ray tube in the electric field sharing type electron gun will be described below. That is, regarding the central electron beam (green), when passing through the burring member 104, the force received from the vertical direction is larger than the force received from the horizontal direction. On the other hand, in the flat pressed part 103, the force received from the horizontal direction is larger than the force received from the vertical direction. By such an action, the central electron beam (green) becomes a spot having a round shape on the phosphor screen surface.

Regarding the electron beams (red and blue) at both ends, of the three electron beams passing through the burring member 104, the force received from the vertical direction is greater than the force received from the horizontal direction. Moreover, regarding the force received from the horizontal direction, the force received from the end of the oval is larger than the force received from the center of the oval. The coma aberration is corrected by such a difference in the force received from the horizontal direction. In addition, astigmatism is corrected by combining the forces received from the horizontal direction. On the other hand, in the flat pressed part 103, the force received from the vertical direction is larger than the force received from the horizontal direction. Moreover, regarding the force received from the horizontal direction, the force received from the horizontal end direction of the flat plate pressed part 103 is smaller than the force received from the central direction. By such an action, the electron beams (red and blue) at both ends become spots having a round shape on the phosphor screen surface.

A large-diameter electron gun in which an electric field extension method is superimposed on an electric field sharing method is known, for example, from Japanese Patent Application Laid-Open No. 8-22780. In the electron gun disclosed in this publication, a focusing electrode 7 to which a focus voltage is applied and a final accelerating electrode 8 to which an anode voltage is applied are coaxially arranged on the focusing electrode 7 and an anode voltage. An auxiliary electrode 9 (having the same function as the intermediate electrode in the present invention) to which a voltage higher than the anode voltage is applied is provided. The cross-sectional shape of the cylindrical auxiliary electrode 9 is an oval.

[0011]

In order to reduce the number of parts constituting the focus electrode 5 and the anode electrode 6,
An electrode component having a structure in which a flat pressed component 103 and a burring member 104 are integrated is known. That is, FIG.
As shown in FIG. 1A, a metal plate 201 is subjected to drawing, and a bottom surface 20 is formed on a side surface 202 and a bottom of the side surface 202.
Form 3 Next, the tip of the side surface 202 is pressed to form a curling portion 204 (FIG. 1).
0 (B)). Thereafter, an electron beam passage hole 205 is formed in the bottom surface 203 by press working (see FIG. 10C). In the electrode component having such a structure, there is a problem in manufacturing that the processing accuracy of the curved surface of the curling portion 204 is low, and the characteristics of the main focus lens formed by the electrode component are not stable. In addition, the length (L ₄ ) of the curling portion 204 extending outward is short,
Easy to deform during beading. In addition, it is necessary to separately attach a beading attachment member to such an electrode component, and to perform beading processing on the attachment member, so that there is a problem that the total number of components cannot be reduced.

Alternatively, as shown in FIG. 11A, the metal plate 11 is subjected to deep drawing to
And the first cylindrical side wall 1 extending from the flange 12
3 and a top surface portion 14 extending from the first side wall 13. Next, as shown in FIG.
Is subjected to reverse deep drawing, and is turned inward from the end of the first side wall 13 so as to extend in parallel with the first side wall 13, and a cylindrical second side wall 15. Is formed at the end of the bottom. Thereafter, three electron beam passage holes 17 (17A, 17B, 17C) are formed in the bottom portion 16 by a press method (see FIG. 11C). In the electrode component having such a structure, the length (L ₅ ) of the first side wall 13 is longer than the length (L ₆ ) of the second side wall 15.
That is, the flange portion 12 is located at a position farther than the position of the bottom surface portion 16 with reference to the end portion (top surface portion 14) of the first side wall 13. In addition, such an electrode component is incorporated in the electron gun with reference to the flange portion 12.

In the electrode component having the structure shown in FIG. 11 (C), although a high precision is required for the processing accuracy for the bottom surface 16 extending from the end of the second side wall 15, it is difficult to manufacture.
Length L of first side wall 13 as a reference when assembling electrode parts
_5, and the main characteristics of the focusing lens defining a second side wall 15 must be performed two positions management such length L _6, there is produced with high precision is a problem that extremely difficult.

In the electron gun disclosed in Japanese Patent Application Laid-Open No. H8-22780, by making the auxiliary electrode longer,
It is possible to further increase the aperture of the main focus lens. However, when the auxiliary electrode is lengthened, the electric field between the focusing electrode 7, the auxiliary electrode 9, and the final acceleration electrode 8 is weakened, and the shape of the end plates 10 and 12 that close the focusing electrode 7 and the final acceleration electrode 8 is not enough. It is difficult to simultaneously satisfy the spot shape and convergence of the electron beam of the book. That is, the penetration of the electric field into the electron beam passage holes provided in the end plates 10 and 12 is weakened, and the correction effect of the lens formed here is reduced. Therefore, the length of the auxiliary electrode 9 is limited, and it is difficult to manufacture an electron gun having a larger diameter.

Therefore, a first object of the present invention is to reduce the number of electrode parts of an electron gun constituting a main focus lens such as a focus electrode and an anode electrode, and to manufacture the electron gun with high accuracy. It is an object of the present invention to provide an electrode part of an electron gun for a color cathode ray tube, a method of manufacturing the same, and an anode electrode and a focus electrode of the electron gun for a color cathode ray tube, which can be incorporated into a color cathode ray tube. Second embodiment of the present invention
It is an object of the present invention to provide a long intermediate electrode and a method for manufacturing the same, which can manufacture an electron gun having a larger diameter by superposing an electric field extension method on an electric field sharing method.

[0016]

In order to achieve the first object, an electrode part of an electron gun for a color cathode ray tube according to the present invention comprises (a) a flange portion and (b) a cylindrical member extending from the flange portion. (C) a cylindrical second side wall that is folded inward from an end of the first side wall and extends in parallel with the first side wall; and (d) the second side wall. Formed at the end of the
A flange portion, a first side wall, a second side wall, and a bottom surface portion are integrally formed by a deep drawing process from a metal plate, and a length of the first side wall is formed. The length is shorter than the length of the second side wall.

The anode electrode of the electron gun for a color cathode ray tube according to the present invention for achieving the first object is manufactured by (a) the above-mentioned electrode component and (b) drawing, and has an electron beam passing through the bottom. It is composed of a drawn part provided with a hole, and is characterized in that the bottom part of the electrode part and the bottom part of the drawn part are joined. Further, a focus electrode of a color cathode ray tube electron gun according to the present invention for achieving the first object is provided with the above-mentioned electrode component of the present invention.

In order to achieve the first object, a method of manufacturing an electrode part of an electron gun for a color cathode ray tube according to the present invention is as follows.
(A) deep drawing a metal plate to form a flange portion, a cylindrical first side wall extending from the flange portion, and a top surface portion extending from an end of the first side wall; A reverse second deep drawing process is performed on the top surface portion, and a cylindrical second side wall which is folded inward from an end of the first side wall and extends in parallel with the first side wall, and an end of the second side wall Forming a bottom portion extending from the portion, and (c) providing an electron beam passage hole in the bottom portion, wherein the length of the first side wall is shorter than the length of the second side wall. And

In the electrode component of the electron gun for a color cathode ray tube or the method of manufacturing the same according to the present invention, the electrode component constitutes a main focus lens of an electric field sharing type, and the electron beam passage hole provided on the bottom portion is provided with a main focus lens. It is preferable to correct the astigmatism and the coma of the electron beam in the above.

According to the method for manufacturing an electrode component of an electron gun for a color cathode ray tube of the present invention, an electrode component forming a focus electrode, an electrode component forming an anode electrode, or an electrode component forming an intermediate electrode can be manufactured. . In a method for manufacturing a focus electrode or an anode electrode, which is one aspect of the method for manufacturing an electrode component of a color cathode ray tube electron gun of the present invention, the electrode component manufactured by the above-described manufacturing method of the present invention and a drawing process. Then, the drawn part having the electron beam passage hole formed at the bottom may be joined to the bottom part of the electrode part and the bottom part of the drawn part.

The intermediate electrode of the electron gun for a color cathode ray tube according to the present invention for achieving the above-mentioned second object is constituted by joining two of the above-mentioned electrode parts at their bottom surfaces, and comprises a focus electrode and an anode electrode. And a voltage higher than the voltage applied to the focus electrode and lower than the voltage applied to the anode electrode is applied. The position of the bottom surface of the electrode component constituting the intermediate electrode deviates from the position on the Z-axis corresponding to the potential of the intermediate electrode in the potential distribution on the Z-axis determined by the potentials of the focus electrode, the intermediate electrode, and the anode electrode. It is preferable to set the position. The voltage applied to the intermediate electrode can be given by a free potential induced by a voltage applied to the focus electrode and a voltage applied to the anode electrode.

A second object of the present invention is that a voltage higher than the voltage applied to the focus electrode and lower than the voltage applied to the anode electrode is applied between the focus electrode and the anode electrode. A method of manufacturing an intermediate electrode of an electron gun for a color cathode ray tube, comprising joining two of the electrode parts obtained by the above-described method of manufacturing an electrode part at their bottom surfaces, thereby manufacturing an intermediate electrode. The present invention can be achieved by a method for manufacturing an intermediate electrode of a color cathode ray tube electron gun according to the present invention.

In the electrode part of the electron gun for a color cathode ray tube or the method of manufacturing the same according to the present invention, the length of the first side wall is shorter than the length of the second side wall. That is, the flange portion is located at a position closer to the inside of the end portion of the first side wall (top surface portion) than the position of the bottom portion extending from the cylindrical second side wall. The electrode component can be incorporated in the electron gun with reference to the bottom surface. Therefore, it is not necessary to manage the length of the first side wall in manufacturing, and only the length of the second side wall needs to be managed. Therefore, it is possible to easily manufacture the electrode component with high accuracy.

In the intermediate electrode of the electron gun for a color cathode ray tube or the method of manufacturing the same according to the present invention, since the intermediate electrode can be lengthened, the gradient of the potential distribution on the Z axis in the main focus lens can be made gentler. , to enlarge the diameter of the effective main focus lens, also, it is possible to reduce the spherical aberration coefficient C _s of the main focus lens. In addition, a new lens that can control the shape and convergence of the electron beam is formed by infiltration of the electric field into the electron beam passage hole formed in the intermediate electrode. The degree of freedom of design for achieving both convergence and convergence is increased.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings based on embodiments of the invention (abbreviated as embodiments).

(Embodiment 1) FIG. 1C is a schematic sectional view of an electrode part 10 of a color cathode ray tube electron gun according to the present invention, which constitutes a focus electrode and an anode electrode.
The electrode component 10 viewed from above is shown in the schematic diagram of FIG. The electron gun has cathodes KR, KG, and KB, a first electrode (control electrode) 1, a second electrode (acceleration electrode) 2, and a third
Electrode 3, fourth electrode 4, focus electrode (fifth electrode) 5,
It comprises an anode electrode (sixth electrode) 6 and a shield cup 7. The focus electrode 5 and the anode electrode 6 constitute a main focus lens. Focus voltage V _f of 6kV~10kV from the stem (not shown) is applied to the third electrode 3 and the focus electrode 5.
On the other hand, the anode electrode 6 has an anode button (not shown).
For example, from 27kV anode voltage V _a of the high pressure is applied. The same potential is applied to the second electrode (acceleration electrode) 2 and the fourth electrode 4. In this electron gun, the cathode K
The three electron beams generated by R, KG, and KB and controlled by the first electrode (control electrode) 1 and the second electrode (acceleration electrode) 2 are the third electrode 4, the fourth electrode 4, and the focus electrode. The divergence angle is controlled by the front electron lens formed by the (fifth electrode) 5, and the light is focused by the main focus lens formed by the focus electrode (fifth electrode) 5 and the anode electrode (sixth electrode) 6.

The electrode component 10 includes a flange portion 12, a first cylindrical side wall 13 extending from the flange portion 12, a second cylindrical side wall 15, and a bottom surface portion 16. The cylindrical second side wall 15 is folded inward from the end of the first side wall 13 and extends in parallel with the first side wall 13.
The bottom portion 16 is formed at an end of the second side wall 15,
Three electron beam passage holes 17 (17A, 17A,
17B, 17C) are provided. These flange portion 12, first side wall 13, second side wall 15, and bottom portion 1
6 is integrally formed from the metal plate 11 by deep drawing. The length L ₂ of the first side wall 13 is
Shorter than the length L ₁ of the side wall 15 of the. It is preferable that the cross-sectional shape of the first side wall 13 and the second side wall 15 in a direction perpendicular to the axis is a shape in which a semicircle and a line segment are combined.

The electrode component 10 forms a main focus lens of the electric field sharing type. The three electron beam passage holes 17 formed in the bottom portion 16 correct astigmatism and coma of the electron beam in the main focus lens. The specific shape of the central electron beam passage hole 17B is preferably, for example, an ellipse having a major axis in a direction parallel to the vertical direction of the electron beam or a shape similar to an ellipse, but is not limited thereto. Absent. The specific shapes of the left and right electron beam passage holes 17A and 17C are, for example, a combination of two ellipses or ellipses, a combination of ellipses or ellipsoids and arcs, or an electron beam. It is preferable to use a circular shape configured to pass a position deviating from the center of the circle, but the present invention is not limited thereto.

The bead glass mounting portion 1 is provided on the flange portion 12.
8 are provided in two places. By attaching bead glass to these bead glass attachment portions 18,
The electrode component 10 can be incorporated in the electron gun.

The electrode component 1 shown in FIG. 1C and FIG.
0 with reference to FIGS. 1A and 1B.
This will be described below. First, as shown in FIG. 1A, the metal plate 11 is deep drawn, and a flange portion 12, a cylindrical first side wall 13 extending from the flange portion 12, and an end of the first side wall 13 are formed. A top surface portion 14 extending from the portion is formed. Then, as shown in FIG. 1B, reverse top drawing is performed on the top surface portion 14, and the first side wall 13 is folded inward from the end portion (the top surface portion 14) to form the first side wall 13. A cylindrical second side wall 15 extending in parallel and a bottom surface portion 16 extending from an end of the second side wall 15 are formed. After that, three electron beam passage holes 17 (17
A, 17B, and 17C) (see FIG. 1C).
Here, reverse deep drawing is performed so that the length L ₂ of the first side wall 13 is shorter than the length L ₁ of the second side wall 15.
Here, the relationship between L ₁ and L ₂ is 0.4 L ₁ ≦ L ₂ ≦ 0.95
It is desirable to satisfy the L _1. The horizontal width of the electrode member 10 is, for example, 20 to 22 mm, the length L1 of the second side wall 15 is ₁ to 7 mm, and the thickness of the metal plate 11 is 0.2 to 0.5 mm. It is preferable to use about stainless steel.

An anode electrode (sixth electrode) 6 and a focus electrode (fifth electrode) 5 are manufactured from the electrode component 10 thus manufactured. In producing the anode electrode 6,
As shown in a schematic sectional view below FIG. 4A and a schematic plan view in FIG. 4B, a drawn part (drift space part) 20 is drawn from a metal plate by drawing. Make it. The bottom 21 is provided with three electron beam passage holes 22A, 22B and 22C by a press method. Then, the bottom portion 21 of the drawn part (drift space part) 20
And the bottom part 16 of the electrode component 10 are joined by, for example, a laser welding method or a resistance welding method. Thus, FIG.
The anode electrode shown in FIG. The height of the drawn part (drift space part) 20 is 12 to 1
It is about 4 mm. By joining the bottom part 21 of the drawn part (drift space part) 20 and the bottom part 16 of the electrode part 10, the thickness of the joined part is increased, and a strong electric field can be formed. The number of components of the anode electrode 6 is two, and one component can be reduced as compared with the anode electrode 6 having the structure shown in FIG.

The focus electrode 5 includes a front lens component 30 formed by drawing and formed with three electron beam passage holes at an end of a drawn part 20 of an assembly having the same structure as the anode electrode 6. For example, it can be manufactured by joining by a laser welding method or a resistance welding method. The number of parts of the focus electrode 5 is three, and the focus electrode 5 having the structure shown in FIG.
The number of parts can be reduced by one point as compared with.

The thus prepared anode electrode (sixth electrode)
FIG. 5 shows a schematic cross-sectional view of the electrode 6 and the focus electrode (fifth electrode) 5 and their arrangement. The electrode component 10 in the anode electrode 6 and the focus electrode 5
And the shape of the electron beam passage holes may be the same or different.

(Embodiment 2) Embodiment 2 relates to an intermediate electrode of a color cathode ray tube electron gun and a method of manufacturing the same. FIG. 6A is a conceptual diagram of the electron gun according to the second embodiment. The electron gun according to the second embodiment differs from the electron gun according to the first embodiment shown in FIG. 3 in that an intermediate electrode is provided between a focus electrode (fifth electrode) 5 and an anode electrode (sixth electrode) 6. 40 in that it is a diameter electron gun in which the electric field extension method is superimposed on the electric field sharing method. Focus electrode (fifth electrode) 5, intermediate electrode 40, and anode electrode (sixth electrode) 6
Thereby, a main focus lens is formed. FIG. 7 shows a schematic cross-sectional view of the focus electrode (fifth electrode) 5, intermediate electrode 40, and anode electrode (sixth electrode) 6.

[0035] the intermediate electrode 40 is higher than the voltage V _f applied to the focusing electrode 5, a low voltage V _m than the voltage V _a applied to the anode electrode 6 is applied. Intermediate electrode 40
Voltage V _m to be applied may be supplied from similar to the focus voltage V _f stem (not shown), the resistor 42,
It may be supplied by dividing the anode voltage V _a high-pressure by 43. The resistors 42 and 43 can be manufactured by, for example, printing a resistance pattern on a ceramic substrate. One end of the resistor 42 is connected to the anode electrode 6 to which the anode voltage V _a of approximately 27kV is applied. Further, the other end of the resistor 42 and one end of the resistor 43 are connected to the intermediate electrode 40, and the intermediate electrode 40
Voltage V _m of ~20kV is applied. The other end of the resistor 43 is grounded. The focus electrode 5 has, for example, 6
Focus voltage V _f of ~10kV is applied. Incidentally, without supplying voltage to the intermediate electrode 40, it is also possible to keep the intermediate electrode 40 to the free potential induced by the focus voltage V _f applied to the anode voltage V _a and the focus electrode 5 applied to the anode electrode 6 .

As shown in FIG. 7, the intermediate electrode 40 is manufactured by joining two of the electrode components 10 described in the first embodiment at their bottom portions 16. Joining is
It can be performed by a laser welding method or a resistance welding method. In the second embodiment, one electric field correction electrode portion 41 is formed by joining two of the electrode components 10 at their bottom portions 16. Electrode component 1 constituting intermediate electrode
Position of the bottom surface portion 16 of 0, i.e., the position of the field correction electrode 41 corresponds to the potential V _m of the intermediate electrodes in the Z-axis on the potential distribution determined by the respective potentials of the focusing electrode and the intermediate electrode and the anode electrode it is preferable that the position deviated from the position Z _m on the Z axis. As a result, the electric field penetrates into the electron beam passage hole provided in the intermediate electrode 40, and a new lens capable of controlling the shape and convergence of the electron beam is formed therein. As a result, the effect of correcting the electric field is improved, and the degree of freedom in designing an electron gun for achieving both the optimum shape and convergence of the electron beam is increased. That is, three solutions of the beam spot shape, beam spot size, and convergence of the electron beam can be obtained based on the following seven parameters. Top surface portion 14 of electrode component 10 constituting intermediate electrode 40 facing anode electrode 6, which is opposite to focus electrode 5. Shape Top surface 1 of electrode component 10 constituting anode electrode 6
4 Shape of Electron Beam Passing Hole 17 of Electrode Component 10 Constituting Anode Electrode 6 Top Surface 14 of Electrode Component 10 Constituting Focus Electrode 5 Shape of Electron Beam Passing Hole 17 of Electrode Component 10 Constituting Focus Electrode 5

On the other hand, in the electron gun disclosed in JP-A-8-22780, three solutions of a beam spot shape, a beam spot size, and convergence of an electron beam are obtained based on the following five parameters. The cylindrical body 14 of the auxiliary electrode 9 The cylindrical body 11 of the focusing electrode 7 The electron beam passage hole 1 in the end plate 10 of the focusing electrode 7
Shapes of Oa, 10b, 10c Cylindrical body 13 of final acceleration electrode 8 Shapes of electron beam passage holes 12a, 12b, 12c in end plate 12 of final acceleration electrode 8

FIG. 6B shows a potential distribution on the Z-axis.
By arranging the intermediate electrode 40 having a potential V _m, improves the correction effect of the electric field by the electric field correcting electrode unit 41, it is possible to elongate the intermediate electrode 40, as a result, the focus voltage V _f and the anode voltage V _The potential distribution on the Z-axis between _a and a becomes gentle as indicated by “A” in FIG. That is, the potential difference between the focus electrode 5 and the intermediate electrode 40 and the potential difference between the intermediate electrode 40 and the anode electrode 6 can be reduced, so that the distance between the electrodes can be reduced. Further, the influence of the electric field from the neck can be reduced. This extends the electric field,
It is possible to enlarge the diameter of the main focus lens, it is possible to reduce the spherical aberration coefficient C _s, it becomes possible to achieve high resolution on the phosphor screen.
The potential distribution on the Z axis indicated by “B” in FIG. 6B is the potential distribution on the Z axis of the electron gun shown in FIG.

In the manufacture of the intermediate electrode 40 according to the second embodiment, the length L ₁ of the second side wall 15 of the electrode component 10 is set.
Can be controlled with high accuracy, a high-quality intermediate electrode 40 can be manufactured, the assembly of the intermediate electrode 40 is easy, and the accuracy at the time of incorporation into an electron gun maintains high accuracy. be able to.

FIG. 8 shows a modification of the intermediate electrode 40A. The intermediate electrode 40 </ b> A is manufactured by joining two of the electrode components 10 described in the first embodiment at their bottom portions 16 via a metal spacer 44. That is, in the intermediate electrode 40A shown in FIG. 8, the number of the electric field correction electrode portions 41 is two. Other structures are described in Embodiment 2.
Therefore, detailed description is omitted. In this case, even in this case, the electric field correction electrode portion 41A,
Each position of 41B is determined by the respective potentials of the focus electrode, the intermediate electrode, and the anode electrode.
Z corresponding to the potential V _m of the intermediate electrodes in the axial potential distribution
It is preferable that the position deviated from the position Z _m on the axis. In the intermediate electrode 40A, items in the above seven parameters are the shape of the electric field correction electrode portion 41A of the intermediate electrode 40A facing the focus electrode 5 and the electric field correction electrode portion 41B of the intermediate electrode 40A facing the anode electrode 6. , And three solutions of the beam spot shape, beam spot size, and convergence of the electron beam can be obtained based on the eight parameters.

The number of intermediate electrodes 40 is not limited to one, but may be two or more. Thus, the potential gradient can be made gentler.

Although the present invention has been described based on the embodiments of the present invention, the present invention is not limited to these embodiments. The materials, dimensions, and numerical values described in the embodiments of the present invention are examples, and can be changed as appropriate. The present invention is, for example, a bipotential focus lens type, a unipotential focus lens type, a high bipotential focus lens type, a tripotential focus lens type, a high unipotential focus lens type, a biunipotential focus lens type, a uni-bipotential focus lens type, The present invention can be applied to other compound lens type electron guns for color cathode ray tubes.

[0043]

According to the present invention, the accuracy control point of the electrode component may be one point (the length L ₁ of the second side wall), and the electrode component of high precision can be manufactured easily and with high productivity. be able to. Further, it can be incorporated into the electron gun with high accuracy. Moreover, the number of components constituting the focus electrode and the anode electrode can be reduced. Furthermore, according to the intermediate electrode or the method of manufacturing a color cathode-ray tube electron gun of the present invention, to enlarge the diameter of the effective main focus lens, also is possible to reduce the spherical aberration coefficient C _s in the main focus lens Not only can this be done, but the degree of freedom in designing the electron gun increases.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining an electrode component of a color cathode ray tube electron gun of the present invention and a method of manufacturing the same.

FIG. 2 is a schematic plan view of an electrode component of the electron gun for a color cathode ray tube according to the present invention.

FIG. 3 is a conceptual diagram of a bi-potential type electron gun.

FIG. 4 is a schematic sectional view of an anode electrode of the electron gun for a color cathode ray tube of the present invention, and a schematic plan view of a drawn part.

FIG. 5 is a schematic sectional view of a focus electrode and an anode electrode in the electron gun for a color cathode ray tube of the present invention.

FIG. 6 is a conceptual diagram of an electron gun having an intermediate electrode according to the present invention, and a graph schematically showing a potential distribution on the Z-axis determined by respective potentials of a focus electrode, an intermediate electrode, and an anode electrode.

FIG. 7 is a schematic sectional view of a focus electrode, an intermediate electrode, and an anode electrode in the electron gun for a color cathode ray tube of the present invention.

FIG. 8 is a schematic sectional view of another embodiment of the intermediate electrode in the electron gun for a color cathode ray tube of the present invention.

FIG. 9 is a schematic sectional view and a schematic plan view of a conventional focus electrode and anode electrode.

FIG. 10 is a view for explaining a manufacturing process of an electrode part having a conventional structure in which a flat pressed part and a drawn pressed part are integrated.

FIG. 11 is a diagram for explaining another manufacturing process of an electrode component having a conventional structure in which a flat plate pressing component and a drawing pressing component are integrated, which is different from FIG.

[Explanation of symbols]

KR, KG, KB ... cathode, 1 ... first electrode (control electrode), 2 ... second electrode (acceleration electrode), 3 ...
3rd electrode, 4 ... 4th electrode, 5 ... Focus electrode (5th electrode), 6 ... Anode electrode (6th electrode),
7 ... shield cup, 11 ... metal plate, 12 ...
・ Flange part, 13 ・ ・ ・ First side wall, 14 ・ ・ ・ Top surface part, 15 ・ ・ ・ Second side wall, 16 ・ ・ ・ Bottom part, 17,
17A, 17B, 17C, 22A, 22B, 22C ...
・ Electron beam passage hole, 18 ・ ・ ・ Bead glass mounting part,
20 ・ ・ ・ Drawing parts (drift space parts), 21 ・
..Bottom part, 30... Front lens components, 40, 40
A: Intermediate electrode, 41, 41A, 41B: Electric field correction electrode part, 42, 43: Resistance, 44: Spacer

Claims (8)

[Claims] (A) a flange portion; (b) a cylindrical first side wall extending from the flange portion; and (c) a first side wall which is folded inward from an end of the first side wall to form the first side wall. A second cylindrical side wall extending in parallel with the side wall; and (d) a bottom surface formed at an end of the second side wall and provided with an electron beam passage hole. The second side wall and the bottom surface are integrally formed by deep drawing from a metal plate, and the length of the first side wall is shorter than the length of the second side wall. Electrode parts for guns. 2. An electrode component forms a main focus lens of an electric field sharing type, and an electron beam passage hole provided in a bottom portion corrects astigmatism and coma of an electron beam in the main focus lens. The electrode component of the electron gun for a color cathode ray tube according to claim 1. 3. An electrode part according to claim 1, and (b) a drawn part formed by drawing and provided with an electron beam passage hole at the bottom. An anode electrode for an electron gun for a color cathode ray tube, comprising a bottom portion and a bottom portion of a drawn part. 4. A focus electrode for an electron gun for a color cathode ray tube, comprising the electrode component according to claim 1. 5. An electrode component according to claim 1, wherein the two electrode components are joined at their bottom portions, and are disposed between a focus electrode and an anode electrode. An intermediate electrode for an electron gun for a color cathode ray tube, wherein a high voltage is applied and a voltage lower than a voltage applied to an anode electrode is applied. 6. A step of deep drawing a metal plate to form a flange portion, a cylindrical first side wall extending from the flange portion, and a top surface portion extending from an end of the first side wall. (B) applying a reverse deep drawing process to the top surface portion, turning inward from an end of the first side wall, and extending in parallel with the first side wall; Forming a bottom surface extending from the end of the second side wall; and (c) providing an electron beam passage hole in the bottom surface. The length of the first side wall is greater than the length of the second side wall. A method for producing an electrode part of an electron gun for a color cathode ray tube, wherein the electrode part is also short. 7. An electrode component constitutes a main focus lens of an electric field sharing type, and an electron beam passage hole provided in a bottom portion corrects astigmatism and coma of the electron beam in the main focus lens. The method for producing an electrode part of an electron gun for a color cathode ray tube according to claim 6, wherein 8. An electron gun for a color cathode ray tube, wherein said electron gun is provided between a focus electrode and an anode electrode, wherein a voltage higher than a voltage applied to the focus electrode and lower than a voltage applied to the anode electrode is applied. A method of manufacturing an intermediate electrode, wherein two of the electrode components obtained by the manufacturing method according to claim 6 are joined at their bottom surfaces to manufacture an intermediate electrode. A method for manufacturing an intermediate electrode of an electron gun for a cathode ray tube.