JPH05225928A - Color picture tube - Google Patents

Abstract

PURPOSE:To provide a color picture tube having a one gun three beams type electron gun in which the aperture of a main electron lens is enlarged and spherical aberration is reduced so as to reduce a beam spot diameter. CONSTITUTION:A color picture tube is composed of a triple portion T, which includes plural electron beam generating sources 12-14 arranged on one plane, and a main electron lens L, which consists of focusing and accelerating electrodes 19, 20 commonly focusing plural electron beams, a deflecting plate 21 arranged on the output side of the lens L. The focusing electrode 19 consists of the center portion 19a of large aperture and both end portions 19b, 19c of small aperture, and the accelerating electrode 20 consists of one end portion 20a of large aperture and the other end portion 20b of small aperture. The one end portion 20a is inserted in the center portion 19a, and the other end portion 20b passes through the one end portion 19c and is extended to the outside of the focusing electrode 19, and the both end portions 19b, 19c, together with the other end portion 20b, are equipped with an electron gun insulating supported by electrode supporting bars 22, 23.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color picture tube, and more particularly to a color picture tube which is used in a television or a terminal display and has a small electron beam spot diameter and high resolution.

[0002]

2. Description of the Related Art Generally, a color picture tube used for color image display is composed of a panel section which is a picture screen, a neck section for accommodating an electron gun, and a funnel section for connecting the panel section and the neck section. From the funnel portion to the neck portion, a deflection device for mounting an electron beam emitted from an electron gun on a fluorescent screen coated and formed on the inner surface of the panel is mounted.

The electron gun housed in the neck portion is provided with various electrodes such as a cathode electrode, a control electrode, a focusing electrode and an accelerating electrode, and an electron beam from the cathode electrode is modulated by a signal applied to the control electrode. The electron beam is made into a required cross-sectional shape through the focusing electrode and the accelerating electrode, energy is applied, and the electron beam is projected onto the phosphor screen. The electron beam, on the way from the electron gun to the fluorescent screen, by the deflection device provided from the funnel portion to the neck portion,
An image is formed on the phosphor screen by being deflected in the horizontal and vertical directions.

In this type of color picture tube, in order to make the image displayed on the fluorescent screen highly precise, it is necessary to reduce the spot diameter of the electron beam on the fluorescent screen (screen). It depends on the performance of the electron gun.

As described above, the electron gun generates an electron beam and controls the generated electron beam by a three-pole portion (cathode electrode and control electrode) and an electron beam controlled by the three-pole portion. The main electron lens unit (focusing electrode and accelerating electrode) for focusing, accelerating, and concentrating the light beam is a factor that greatly affects the spot diameter of the electron beam in these configurations. Spherical aberration can be mentioned. If the spherical aberration of the main electron lens can be reduced, the spot diameter of the electron beam can be reduced and a high-definition image can be obtained. It is well known that the spherical aberration of the main electron lens can be reduced by enlarging the diameter of the electrode forming the main electron lens.

By the way, the main electron lens is usually composed of an electrostatic lens, and the electrostatic lens has a plurality of electrodes each having an electron beam passage hole arranged coaxially. It is formed by applying a predetermined voltage to. Conventionally, there are several types of this electrostatic lens depending on the configuration of the electrode, but basically, in any type, the diameter of the electron beam passage hole is made as large as possible to increase the diameter of the electrode. (Japanese Patent Laid-Open No. 59-21)
5640 publication).

However, since the electron gun is arranged in the neck portion of the color picture tube having a small diameter, the diameter of the electron beam passage hole is naturally limited. If the diameter of the neck portion is enlarged to enlarge the diameter of the electron beam passage hole, the deflection power of the deflection yoke arranged outside the funnel portion to the neck portion is increased. Therefore, it is not preferable to increase the diameter of the neck portion.

Conventionally, as a means for solving the above-mentioned point, instead of providing three parallel electron lenses on the same plane, this is constituted by one large-aperture electron lens, and the above-mentioned large-aperture electron lens is provided. There is known an electron gun of a type in which three electron beams are allowed to cross each other in a central portion of the lens so as to maximize the lens performance, that is, a so-called 1-gun 3-beam electron gun. (See, for example, Japanese Examined Patent Publication No. 49-5591).

FIGS. 4 (a) and 4 (b) show an example of an electron gun of the above-mentioned type. FIG. 4 (a) is a sectional view of a plane orthogonal to the arrangement direction of the three cathodes, b) is a cross-sectional configuration diagram of a plane in the arrangement direction.

In FIG. 4, K _R ', K _G ' and K _B 'are red,
Cathode corresponding to each color of green and blue, G ₁ 'is the first electrode, G
₂ 'second electrode, G ₃ is' third electrode, G ₄ 'is the fourth electrode, G _5'
Is a fifth electrode, A'and B'are electrostatic deflection plates, S'is a screen, I'is an insulating support member, and R'is a high resistance.

In the following description, only in the one-gun three-beam system electron gun, the direction in which the electron sources (cathodes) are arranged is the x direction, the direction orthogonal to the x direction is the y direction, and the tube is the tube. The axial direction is the z direction.

The cathodes K _R ', K _G ', K _B 'and the first
A triode T'is formed by the electrode G ₁ 'and the second electrode G ₂ ', and a cylindrical third electrode G ₃ ', fourth electrode (focusing electrode) G ₄ ', and fifth electrode G ₅ ', respectively. Thus, a unipotential type main electron lens L'is formed. Also, along the neck of the tube, first to fifth electrodes G ₁ 'to G _5' and electrostatic deflection plates A ', B' insulating support member I which supports the 'a high resistance R'
And are inserted.

In the above structure, three cathodes K _R ',
The electron beam emitted from K _G 'and K _B ' is the first electrode G ₁ '
After the intensity and the like are controlled by the second electron G ₂ ′ and the second electrode G ₂ ′, it is incident on the main electron lens L ′ and hits the center of the main electron lens L ′ at a Fraunhofer condition (condition in which coma aberration becomes zero). Intersect at a position that satisfies The three electron beams which are in a divergent state after this crossing are again directed in the focusing direction by the action of the electrostatic deflection plates A'and B ', and finally converged on the screen S'. It

As described above, the electron gun of the type described above focuses three electron beams in one main electron lens L ', and has only one through hole, which is limited. The diameter of the electronic lens L'can be made larger than the diameter of the neck portion.

[0015]

However, in the above-described one-gun three-beam type electron gun, although the diameter of the electron lens L'can be increased, the main electron lens L'can be arranged along the neck portion N'of the tube. The third to the fifth which constitute
Since the insulating support member I ′ for insulating and supporting the electrodes G ₃ ′ to G ₅ ′ is arranged, only the portion corresponding to the thickness (arrangement region) of the insulating support member I ′ is the third to fifth electrodes G ₃ ′. Through G
Diameter of the electrode ₅ 'so that is limited. In the electron gun of this type, electrostatic deflection plates A ', B' with respect to the supply of voltage to, anode - Dobotan P from the fifth electrode G ₅ 'and inner electrode plate B of the electrostatic deflection plates''supplies, the maximum voltage E _b' maximum voltage E _b to the supplied to the high-resistance R 'by an outer deflector plate a of the divided voltage electrostatic deflection plates', electrostatic deflection plates a', B The outer electron beam passing through'is deflected inward, and the high resistance R'used in this case is arranged along the neck portion N'of the tube. Similarly, the diameters of the electrodes of the _{third to} fifth electrodes G ₃ ′ to G ₅ ′ are limited only in the portion corresponding to the thickness (arrangement region) of the resistor R ′. There is a problem that the diameter of the electrode, that is, the diameter of the main electron lens L'cannot be enlarged sufficiently.

By the way, although it is an electron gun of a one-gun one-beam system instead of the above-mentioned type of electron gun, recently, a large diameter portion is provided for each of the third electrode (focusing electrode) and the fourth electrode (accelerating electrode). The inventors of the present invention have developed an electron gun in which the large-diameter portions are configured to overlap each other so that the diameter of the main electron lens is sufficiently enlarged (see Japanese Patent Laid-Open No. 1-258346). ).

FIG. 5 is a sectional view showing the essential parts of the one-gun one-beam system electron gun disclosed in the above-mentioned Japanese Patent Laid-Open No. 1-258346.

In FIG. 5, G ₃ "is a third electrode (focusing electrode), G ₄ " is a fourth electrode (focusing electrode), I "is an insulating support member, and L" is a third electrode and a fourth electrode. A bipotential type main electron lens, H ″, is an electron beam insertion hole of the third electrode.

The third electrode (focusing electrode) G ₃ "has a large-diameter portion at its center and a small-diameter portion at both ends.
The fourth electrode (focusing electrode) G ₄ ″ has a large diameter portion at one end and a small diameter portion at the other end, and the fourth electrode G ₄ ″ has a large diameter portion within the large diameter portion of the third electrode G ₃ ″. The diameter part is inserted and arranged, and the fourth electrode G ₄ ″
Of the small diameter portion of the other end is extended disposed to the outer "third electrode G ₃ through one end of the" third electrode G _3. Further, the insulating support member I ″ is divided into two parts by removing the outer portions of the large diameter portions of the third electrode G ₃ ″ and the fourth electrode G ₄ ″, and the third electrode G ₃ ″ and The small diameter portion of the fourth electrode G ₄ ″ is configured to hold these electrodes G ₃ ″ and G ₄ ″.

Here, Japanese Unexamined Patent Application Publication No. Hei.
The electron gun disclosed in No. -258346 operates as follows.

The single electron source the electron beam emitted from the (cathode), the third electrode G ₃ via the "electron beam insertion hole H for" third electrode G ₃ "is supplied to the third electrode G ₃ ' And a screen (not shown) after being focused in a bipotential type main electron lens L ″ composed of a fourth electrode G ₄ ″.
Projected on. In the electron gun according to the above configuration, the third electrode G ₃ "is enlarged in a range where it does not come into contact with the inner surface of the neck portion of the tube, so that the diameter of the main electron lens is increased, and thus the spherical surface is increased. The aberration is reduced, the electron beam spot on the screen is reduced,
It is intended to bring about an improvement in resolution.

However, the above-mentioned Japanese Patent Laid-Open No. 1-258346.
The electron gun disclosed in No. 1 is merely a technical means for a one-gun, one-beam type electron gun, and focuses on other types of electron guns, in particular, a plurality (three) electron beams are focused. Further, no description or disclosure is made on the application to an electron gun for focusing.

The present invention is intended to solve the above-mentioned problems, and the purpose thereof is to sufficiently enlarge the diameter of the electrodes constituting the main electron lens, to enlarge the diameter of the main electron lens, and to reduce the spherical aberration. Another object of the present invention is to provide a color picture tube equipped with a 1-gun 3-beam type electron gun whose beam spot diameter is reduced.

[0024]

In order to achieve the above-mentioned object, the present invention is arranged on one plane, each of which is an electron beam.
A triode consisting of a plurality of electron sources for generating beams and a control electrode for controlling these electron beams, a focusing electrode and an accelerating electrode for commonly focusing a plurality of electron beams from the triode. And a bipotential main electron lens consisting of, and an electrostatic deflection plate consisting of a plurality of electrode plates arranged on the screen side of the main electron lens, the focusing electrode has a large central diameter, The accelerating electrode has a large diameter at one end and a small diameter at the other end, and the one end is inside the central portion of the focusing electrode. And the other end extends through one end of the focusing electrode to the outside of the focusing electrode, and both ends of the focusing electrode extend to the outside of the focusing electrode in the acceleration electrode. With the other end extended And it comprises a main unit comprising an electronic gun insulated supported by the electrode support bar.

Further, in order to achieve the above object, according to the present invention, a high resistance with an intermediate tap is arranged in the small-diameter portion of the other end portion of the accelerating electrode and each outer region of the electrostatic deflection plate, One end of the high resistance is connected to the inner electrode plate of the electrostatic deflection plate to which the highest voltage is supplied, the middle tap of the high resistance is connected to the outer electrode plate of the electrostatic deflection plate, and the other end of the high resistance is connected. Is connected to one end of a conductive lead material provided along the neck of the tube, and the other end of the conductive lead material is provided with an electron gun led out of the neck of the tube. It is equipped with the following additional means.

[0026]

According to the above-mentioned main means, according to the present invention, the focusing electrode and the accelerating electrode constituting the bi-potential type main electron lens are insulated in the tube by the electrode supporting rods only at their both ends and one end. Since it is configured to be supported and fixed, it is not necessary to dispose the electrode support rod in the central part of the focusing electrode and the outer part of the other end of the accelerating electrode. The diameter of the other end of the electrode can be increased to be close to the inner diameter of the neck of the tube, thereby maximizing the diameter of the main electron lens. For this reason,
The beam spot diameter obtained on the screen is considerably reduced, and a color picture tube capable of displaying a high resolution image can be obtained.

According to the additional means, high resistance is provided along the neck portion of the tube only in the outer regions of the accelerating electrode and the electrostatic deflection plate. It is not necessary to dispose the high resistance on the outer side of the other end of the accelerating electrode. The diameter of the main electron lens can be enlarged to the maximum, so that the diameter of the main electron lens can be maximized. Even in this case, the beam spot diameter obtained on the screen is considerably reduced, and a color picture tube capable of displaying a high-resolution image can be obtained.

[0028]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic configuration diagram showing an embodiment of a color picture tube according to the present invention.

In FIG. 1, 1 is a panel portion, 2 is a funnel portion, 3 is a neck portion, 4 is a fluorescent screen (screen), 5 is a shadow mask, 6 is a magnetic shield, 7 is a deflection yoke, and 8 is a purity adjusting magnet. , 9 are center beam static convergence adjustment magnets, 10 are side beam static convergence adjustment magnets, 11
Is an electron gun, B _G is a center beam, B _R ,
B _B is a side beam.

To perform the convergence adjustment (static convergence) of such a color picture tube, first, the convergence of the two side beams B _R and B _B is taken, and then the center beam B _G and the side beam B _R ,
I try to concentrate on the B _B convergence point.

On the outer surface of the panel portion 1, a thin film for preventing reflection and electrification, such as SnO ₂ or In, is optionally formed.
A thin film containing ₂ O ₃ or the like is formed in a single layer or multiple layers. Further, although not shown, the funnel portion 2 and the neck portion 3
An inner conductive film made of graphite or the like is deposited on the inner surface of the, and this conductive film electrically connects a high-voltage terminal (not shown) and the electron gun 11.

FIGS. 2A and 2B are sectional views showing an embodiment of the electrode arrangement of the electron gun portion of the color picture tube, wherein FIG. 2A shows three cathodes arranged. FIG. 3B is a sectional configuration diagram of a plane in a direction (y direction) orthogonal to the direction (x direction), and FIG.

In FIG. 2, 12, 13, 14 are green,
Three cathodes arranged in parallel on one plane corresponding to each color of red and blue, 15 is a first electrode, 16 is a second electrode, 17, 19
Is a cylindrical third electrode (focusing electrode) divided into two, 18 is a first deflection plate, 19a is a large diameter portion of the third electrode 19,
b and 19c are a small diameter portion of the third electrode 19, 20 is a cylindrical fourth electrode (accelerating electrode), 20a is a large diameter portion of the fourth electrode 20, 20b is a small diameter portion of the fourth electrode 20, and 21 is Second deflection plate, 22 and 23 are first and second electrode support rods, 24 is high resistance, 24a is an intermediate tap of high resistance 24, 25 is a conductive lead, 26 is a lead terminal, 27 is a high voltage terminal, A, B is second
The pair of electrode plates on the outside and inside of the deflection plate 21, C and D are the first
A pair of electrode plates on the outside and inside of the deflection plate 18, B _G , B _R ,
B _B is green, red, is a three electron beams corresponding to each color of blue.

The cathodes 12, 13, 14 and the first
A triode T is formed by the electrode 15 and the second electrode 16, and the third electrode (focusing electrode) 17 and 19 and the first deflection plate 18 are formed.
A bipotential main electron lens L is formed by the fourth electrode (accelerating electrode) 20 and the second deflecting plate 21. The third electrode (focusing electrode) 19 has a large diameter portion 19a at the center and small diameter portions 19b and 19c at both ends. The fourth electrode (accelerating electrode) 20 has a large diameter portion 20a at one end and the other end portion. The third electrode 1 has a small diameter portion 20b.
The large diameter portion 20a of the fourth electrode 20 is inserted and arranged inside the large diameter portion 19a of the third electrode 19, and the small diameter portion 20b of the fourth electrode 20 passes through the small diameter portion 19c of the third electrode 19 to the third electrode ( It is arranged so as to extend outside the focusing electrode) 19. In addition, the small diameter portions 19b of the first electrode 15, the second electrode 16, the third electrode (focusing electrode) 17, and the third electrode (focusing electrode) 19 are insulated and supported by the first electrode support rods 22, respectively. Small-diameter portion 19 of electrode (focusing electrode) 19
c, the small diameter portion 20b of the fourth electrode (accelerating electrode) 20, the second
The deflection plates 21 are insulated and supported by the second electrode support rods 23, respectively. Further, the third electrode (focusing electrode) 19
The small resistance portion 19c, the small diameter portion 20b of the fourth electrode (accelerating electrode) 20, and the high resistance 24 arranged outside the arrangement portion of the second deflection plate 21 have one end connected to the high voltage E _b supply terminal 27. The pair of electrode plates B electrically connected to each other and the inner side of the second deflection plate 21, the intermediate tap 24a to the pair of electrode plates A on the outer side of the second deflection plate 21, and the other end inside the neck portion 3 of the tube. Each of the conductive leads 25 is formed by vapor deposition and is connected to one end thereof, and the other end of the conductive lead 25 is connected to the lead-out terminal 26.

Here, the third electrode (focusing electrode) 19
The diameter of the fourth electrode (accelerating electrode) 20 is 29 mm in outer diameter of the neck portion 3 in the conventional electron gun of the color picture tube.
The inner diameter of 24.5 mm was about 12 to 13 mm at most.
The outer diameter is φ29 mm (inner diameter φ24.5 mm),
For example, the diameter φ of the large diameter portion 20a of the fourth electrode (accelerating electrode) 20 is 16 mm, and the large diameter portion 1 of the third electrode (focusing electrode) 19 is
The diameter φ of 9a is enlarged to 21 mm.

The electron gun of the color picture tube having the above-mentioned structure is
The operation described below is performed.

The three electron beams B _G , B _R , and B _B emitted from the three cathodes 12, 13 and 14, respectively, are
After the intensity and the like of the first electrode 15 and the second electrode 16 are controlled, they pass through the third electrode (focusing electrode) 17 in a substantially parallel state and are incident on the first deflection plate 18. This first
In the deflecting plate 18, the three electron beams B _G , B
_R, of the B _B, the side beams B _R, but B _B is to receive the slightly deflected to the center beam B _G side, the degree of deflection in this case is Saidobi - beam B _R, B _B is the main electron lens L Is selected so that the light beam is incident on the vicinity of the central portion of, that is, the position satisfying the Fraunhofer condition (condition for reducing coma aberration to zero). Then, the three electron beams B _G , B _R , and B _B incident on the main electron lens L intersect at the substantially central portion of the main electron lens L, and after the intersection, the three electron beams B _G , B _R , and B _B move away from each other and are incident on the second deflecting plate 21. Second deflector 21
, Both side beams B _R and B _B are again deflected toward the center beam B _G side, and the three electron beams B _G are finally deflected on the screen (not shown) by the deflection. , B _R , and B _B are converged into one point.

Further, one end of the high resistance 24 disposed on the outside of each of the small diameter portions 19c and 20b of the third electrode (focusing electrode) 19, the fourth electrode (accelerating electrode) 20 and the second deflecting plate 21, The leads electrically conductively connected to the high voltage terminal 27 and the pair of electrode plates B inside the second deflection plate 21 are connected to apply the maximum voltage E _b, and the intermediate tap 24a of the high resistance 24 is connected to the second tap.
Because be connected to the electrode plates A of the outer pair of deflection plates 21, the outer and inner counter-electrode plate A of the second deflection plate 21, B on both Saidobi - deflecting the beam B _R, B _B The voltage for making it effective is supplied. Further, the high resistance 24
The other end of the conductive lead 25 is connected to one end of a conductive lead 25 deposited along the inner wall of the neck portion 3 of the tube.
Since the other end of the second deflection plate is connected to the lead-out terminal 26, the lead-out terminal 26 is grounded via a potentiometer and / or a variable power source (neither of which is shown), or is directly grounded to the second deflection plate. It is possible to effectively select the supply voltage of the pair of electrode plates A and B on the outer side and the inner side of 21. The conductive lead 25 may be formed by applying graphite instead of depositing a conductive material on the inner wall of the tube.

As described above, according to this embodiment, the third electrode (focusing electrode) 19 has the large diameter portion 19a at the center and the small diameter portions 19b and 19c at both ends, and the fourth electrode (accelerating electrode) 20. Has a large diameter portion 20a at one end and a small diameter portion 20b at the other end, the large diameter portion 20a is inserted and arranged inside the large diameter portion 19a, and the small diameter portion 20b passes through the small diameter portion 19c. Since it is arranged so as to extend outside the third electrode (focusing electrode) 19, the diameter of the main electron lens L can be sufficiently enlarged to near the inner diameter of the neck portion 3 of the tube. Then, each electrode 15, 16, 1
7, 19, 20 and electrode support rods 22, 23 for insulatingly supporting the deflection plates 18, 21 and a third electrode (focusing electrode)
19, each small diameter portion 19c of the fourth electrode (accelerating electrode) 20,
The high resistances 24 arranged on the outer sides of 20b and the second deflecting plate 21 respectively include the third electrode (focusing electrode) 19 and the fourth electrode (accelerating electrode) 2 that constitute the main electron lens L.
0 is not arranged in each of the large diameter portions 19a and 20a, the diameter of the main electron lens L is set to the neck portion 3 of the tube regardless of the presence of the electrode support rods 22 and 23 and the high resistance 24.
It is possible to sufficiently expand it to near the inner diameter of. Further, since the conductive lead 25 is provided along the inner wall of the tube, the second deflecting plate 2 is formed even though the diameter of the main electron lens L is enlarged to near the inner diameter of the neck portion 3 of the tube.
The operation voltage can be effectively supplied to the first and the like.

Next, FIGS. 3 (a) and 3 (b) are sectional views showing another embodiment of the electrode arrangement of the electron gun portion of the color picture tube, wherein FIG. 3 (a) shows three cathodes arranged. FIG. 3B is a cross-sectional configuration diagram of a plane in a direction (y-direction) orthogonal to the direction (x-direction) shown in FIG.

In FIG. 3, 28 is a second high resistance, 29
Is a high resistance, 29a is an intermediate tap of the high resistance 29, and other components that are the same as those shown in FIG. 2 are denoted by the same reference numerals.

In this embodiment, the first electrode 1
5, the second electrode 16, the third electrode (focusing electrode) 17, and the second high resistance 28 along each outside of the first deflection plate 18.
Is newly arranged, and a conductive lead 29 having an intermediate tap 29a is used.
2 has one end connected to the intermediate tap 29a of the conductive lead 29 and the other end connected to the lead-out terminal 26, except that the other end of the conductive lead 29 is electrically open. The configuration is similar to that of the above-described embodiment shown in FIG.

In this embodiment, three electron beams B _G ,
The operation for B _R and B _B is almost the same as that of the above-described embodiment shown in FIG. 2, so the operation for the three electron beams B _G , B _R and B _B will be more detailed. The description is omitted.

However, in this embodiment, the other end of the conductive lead 29 is not directly connected to the lead-out terminal 26, and the intermediate tap 29a of the conductive lead 29 is led out via the high resistance 28. Is electrically connected to the
The potential of the gate 29 itself does not become the ground potential or a relatively low potential, but is higher than those potentials by a voltage drop due to the high resistance 28. Therefore, in order to make the potential of the intermediate tap 24a of the high resistance 24 in the present embodiment the same as the potential of the intermediate tap 24a in the aforementioned embodiment shown in FIG. When the resistance value is set, the conductive lead 25 is at the ground potential or a relatively low potential as in the embodiment shown in FIG. 2, and the conductive lead 25 and various electrodes, In particular,
When the withstand voltage between the third electrode (focusing electrode) 19 becomes a problem, the problem can be effectively solved by adopting the configuration of this embodiment.

As described above, according to this embodiment, the same effect as that of the above-described embodiment shown in FIG. 2 is obtained, and the conductive lead 29 and various electrodes, especially the third electrode (focusing) are provided. This also has the effect of improving the withstand voltage between the electrode) 19.

[0047] In each embodiment described above, the first deflection plate C, and D arranged in triode T side of the main electron lens L, both Saidobi - beam B _R, B _B a center beam B _G side The present invention is applied to an electron gun which is deflected toward the central portion of the main electron lens L, but without the first deflecting plates C and D, both side beams B _R and B are arranged. Similarly, for an electron gun having a structure in which the cathodes 13 and 14 which are the electron sources of _B are tilted slightly inward and both side beams B _R and B _B are directed to the vicinity of the center of the main electron lens L from the beginning. Can be applied.

[0048]

As described above, according to the color picture tube of the present invention, the third electrode (focusing electrode) 19 and the fourth electrode (accelerating electrode) 20 constituting the main electron lens L are
Since both ends 19b and 19c and one end 20b are insulated and fixed by the divided electrode support rods 22 and 23, respectively, the central portion 19a of the third electrode (focusing electrode) 19 and the fourth electrode ( The other end 20 of the acceleration electrode 20
It is not necessary to dispose the electrode support rods 22 and 23 on the respective outer portions of a, and the central portion 19a and the fourth electrode (acceleration electrode) of the third electrode (focusing electrode) 19 are reduced by the amount that the electrode support rods 22 and 23 are not disposed. The diameter of the other end 20a of the electrode 20 can be increased to a value close to the inner diameter of the neck portion 3 of the tube, whereby the diameter of the main electron lens L can be maximized. Therefore, the diameter of the beam spot obtained on the screen is reduced, and a color picture tube capable of displaying a high-resolution image can be obtained.

Further, according to the color picture tube of the present invention, at least one end portion 20b of the fourth electrode (accelerating electrode) 20 and each outer portion of the second deflecting plate 21 along the neck portion 3 of the tube. Since the high resistance 24 is provided, the central portion 19a of the third electrode (focusing electrode) 19 and the fourth electrode (accelerating electrode)
It is not necessary to dispose the high resistance 24 on the outer portion of the other end 20a of the second electrode 20, and the high resistance 24 is not disposed. The other end portion 20a of 20) can be enlarged until it is close to the inner diameter of the neck portion 3 of the tube, whereby the same effect as the above-mentioned effect can be obtained.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of a color picture tube according to the present invention.

FIG. 2 is a cross-sectional configuration diagram showing an example of an electrode arrangement of an electron gun portion of the color picture tube of FIG.

FIG. 3 is a cross-sectional configuration diagram showing another embodiment of the electrode arrangement of the electron gun portion of the color picture tube of FIG.

FIG. 4 is a cross-sectional configuration diagram showing an example of a conventional 1-gun 3-beam type color picture tube electron gun.

FIG. 5 is a cross-sectional configuration diagram showing an example of a main part of an electron gun of a conventional 1-gun 1-beam type picture tube.

[Explanation of symbols]

1 Panel Part 2 Funnel Part 3 Neck Part 4 Fluorescent Screen (Screen) 5 Shadow Mask 6 Magnetic Shield 7 Deflection Yoke 8 Purity Adjusting Magnet 9 Center Beam Static Convergence Adjusting Magnet 10 Side Beam Static Convergence Adjusting Magnet 11 Electron Gun 12, 13, 14 Cathode 15 First electrode 16 Second electrode 17, 19 Third electrode (focusing electrode) 18 First deflection plate 19a Large diameter portion 19b of third electrode 19 19b, 19c Small diameter portion of third electrode 19 Fourth electrode (Acceleration electrode) 20a Large diameter part 20b of the 4th electrode 20, 20c Small diameter part of the 4th electrode 21 2nd deflection plate 22 1st electrode support rod 23 2nd electrode support rod 24, 28 High resistance 25, 29 conductive lead 26 lead-out terminal 27 high-voltage terminal B _G center beam B _R , B _B size DoBeam E _b Maximum voltage

Claims (3)

[Claims] 1. An electronic beam array arranged on one plane.
A triode consisting of a plurality of electron sources for generating beams and a control electrode for controlling these electron beams, a focusing electrode and an accelerating electrode for commonly focusing a plurality of electron beams from the triode. And a bipotential main electron lens consisting of, and an electrostatic deflection plate consisting of a plurality of electrode plates arranged on the screen side of the main electron lens, the focusing electrode has a large central diameter, The accelerating electrode has a large diameter at one end and a small diameter at the other end, and the one end is inside the central portion of the focusing electrode. And the other end extends through one end of the focusing electrode to the outside of the focusing electrode, and both ends of the focusing electrode extend to the outside of the focusing electrode in the acceleration electrode. With the other end extended Color picture tube, characterized in that it comprises an electron gun which is insulated supported by the electrode support bar. 2. A high resistance with an intermediate tap is arranged in a small diameter portion of the other end of the acceleration electrode and each outer area of the electrostatic deflection plate, and one end of the high resistance is supplied with a maximum voltage. The high resistance middle tap is connected to the inner electrode plate of the electrostatic deflection plate, and the high resistance middle tap is connected to the outer electrode plate of the electrostatic deflection plate, and the other end of the high resistance is provided along the neck portion of the tube. 2. The collar according to claim 1, further comprising an electron gun connected to one end of the conductive lead material, and the other end of the conductive lead material is led out of a neck portion of the tube. Picture tube. 3. A high resistance having a first intermediate tap is arranged in a small diameter portion of the other end of the acceleration electrode and each outer region of the electrostatic deflection plate, and the other end of the focusing electrode is connected to the high resistance. A second high resistance is disposed in an outer region of a portion reaching the triode, one end of the first high resistance is connected to an inner electrode plate of the electrostatic deflection plate to which a maximum voltage is supplied, and the first high resistance is connected to the first high resistance. Is connected to the outer electrode plate of the electrostatic deflection plate, and the other end of the first high resistance is connected to one end of a conductive lead material provided along the neck of the tube. Connected,
One end of the second high resistance is connected to the intermediate tap of the conductive lead material, and the other end of the second high resistance is equipped with an electron gun led out of the neck portion of the tube. The color picture tube according to claim 1, wherein