JP2003142011A - Electron gun and its manufacturing method, cathode-ray tube and display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electron gun capable of obtaining optimum hollow beams, a cathode-ray tube and a display device capable of obtaining an image with high brightness and high resolution. SOLUTION: This electron gun 1 has an electron emission suppressing region 9 formed by including laser beam machining utilizing a plasma liberation phenomenon (for example, laser beam machining using femtosecond laser), and is composed of a cathode body structure 2 emitting hollow electron beams having no heat modified part and/or no heat deformed part caused by laser beam machining in the periphery of the electron emission suppressing region 9, and a plurality of electrodes G1 , G2 , and 3. The cathode-ray tube has the electron gun 1. The display device has the cathode-ray tube.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cathode ray tube for displaying information such as images and characters, an electron gun suitable for use in a display device, a manufacturing method thereof, and a cathode ray tube and a display device equipped with this electron gun. Regarding

[0002]

2. Description of the Related Art In the coming broadband era, a television receiver placed in a tea room of a general household plays a role of an information terminal. At that time, it is required to display the character information on a large screen in a high resolution and to display a high quality image such as a digital video disc (DVD) in a powerful large screen in a bright and high definition.

Since the cathode ray tube emits and displays an image by scanning with an electron beam, the beam scanning range becomes wider as the screen size increases, and the luminance of the fluorescent screen decreases with the same cathode current. Therefore, as the screen becomes larger, it is necessary to display an image with a larger cathode current. However, when the cathode current increases, it is generally unavoidable that the electron beam spot diameter (Vss) increases. When the electron beam spot diameter becomes large, the image displayed on the screen becomes dim and the resolution deteriorates.

Conventionally, as measures against this, measures for reducing the spherical aberration of the electronic lens system such as enlargement of the diameter of the main lens system, sharing, multi-stage convergence, etc. have been steadily implemented, but the required level has increased with the times. Combined with what has been done, it is still not enough.

On the other hand, as a solution different from the above, there has been an idea of using a hollow electron beam (hereinafter referred to as a hollow beam). Attempts to use hollow beams have been
Since the 1960s, it has been carried out in a high-frequency amplification vacuum tube, and an attempt to apply a cathode ray tube to an electron gun has been made in the 1970s (see US Pat. No. 4,091,311). It has been known for some time that the characteristics of a cathode ray tube using a hollow beam are good, but it has not been commercialized due to the difficulty of assembly.

A hollow beam electron gun is disclosed in Japanese Patent Laid-Open No. 2001-2001.
It is also proposed in Japanese Patent Publication No. 93438. This technology
This is a method of processing a cathode electron emission region using a laser in order to simplify the structure of a hollow beam electron gun that simultaneously improves both the cathode drive characteristic and the emittance characteristic and improve mass productivity.

[0007]

By the way, in the hollow beam electron gun, it is important that the electron emitting portion of the cathode structure is formed with high precision. However, it is difficult to accurately form an electron emission portion that requires fine processing, and it is difficult to obtain a hollow beam that becomes a finer beam spot on the screen.

In view of the above points, the present invention provides an electron gun capable of obtaining an optimum hollow beam which becomes a fine beam spot on a screen, and a manufacturing method thereof. The present invention provides a cathode ray tube capable of obtaining an image of high brightness and high resolution (high definition), and a display device including the same.

[0009]

The electron gun according to the present invention comprises:
It has an electron emission suppression region formed by including laser processing utilizing the plasma release phenomenon, and a hollow electron beam is formed around this electron emission suppression region without a heat-altered portion or / and a heat deformed portion due to laser processing. It is composed of a cathode structure adapted to emit light and a plurality of electrodes.

In the electron gun of the present invention, since the electron emission suppressing region of the cathode structure is formed by laser processing utilizing the plasma release phenomenon, a thermally altered portion and a protrusion such as a burr are formed around the electron emission suppressing region. There is no heat-deformed part. Therefore, since the electron emission suppressing region having a desired area formed with high precision is provided, it is possible to emit an optimum hollow electron beam having a sufficiently small spot diameter on the screen.

The method of manufacturing an electron gun according to the present invention has a step of forming an electron emission suppression region by performing laser processing utilizing a plasma release phenomenon on a part of the electron emission main body of the cathode structure. A cathode assembly adapted to emit an electron beam is formed.

Laser processing utilizing the plasma release phenomenon is so-called non-thermal processing. In the method of manufacturing an electron gun of the present invention, the electron emission main body of the cathode structure is subjected to laser processing utilizing the plasma liberation phenomenon to form the electron emission suppression region, so that the electron emission region other than the laser irradiation region is heated. It does not affect the target. Therefore, it is possible to accurately create a cathode structure that emits an optimal hollow electron beam.

The cathode ray tube according to the present invention has an electron emission suppression region formed by including laser processing utilizing a plasma release phenomenon, and a heat-altered portion or / and heat generated by laser processing is provided around the electron suppression region. It is provided with an electron gun including a plurality of electrodes and a cathode structure which does not have a deformed portion and emits a hollow electron beam.

Since the cathode ray tube of the present invention is provided with the electron gun having the cathode structure having the electron emission suppressing region of the desired area formed with high precision, the optimum hollow electron beam can be obtained and the high current can be obtained. High resolution images are often obtained.

The display device according to the present invention has an electron emission suppression region formed by including laser processing utilizing a plasma release phenomenon, and a heat-altered portion or / and heat generated by laser processing is provided around the electron suppression region. It is provided with a cathode ray tube having an electron gun composed of a plurality of electrodes and a cathode structure which emits a hollow electron beam without a deformed portion.

Since the display device of the present invention is provided with the above-mentioned cathode ray tube, an optimum hollow electron beam can be obtained and a high resolution display image can be obtained even at a high current.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION An electron gun according to an embodiment of the present invention has an electron emission suppression region formed by including laser processing utilizing a plasma release phenomenon, and laser processing is performed around the electron emission suppression region. It is composed of a plurality of electrodes, and a cathode structure that emits a hollow beam without a heat-altered portion and / or a heat-deformed portion. As the laser processing utilizing the plasma release phenomenon, processing in which an ultrashort pulse laser with an oscillation pulse width of 1 picosecond or less (hereinafter referred to as femtosecond laser) is irradiated can be used. In the case of laser processing utilizing this plasma release phenomenon, so-called non-heating processing is performed without heating.

The electron emission suppression region is formed in the center of a so-called electron emission body having an electron emitting substance, and its area is preferably 5% to 45% of the area of the beam transmission hole of the first electrode. This area depends on the electric field intensity distribution on the cathode surface. The distance between the cathode and the first electrode during operation is 50μ
m, first electrode plate thickness 45 μm, first electrode-second electrode distance 400 μm, first electrode potential 0 V, second electrode potential 600 V
At this time, the area of this electron emission suppression region became the optimum value at about 25% of the area of the beam transmission hole of the first electrode. 5
If it deviates from 45% to 45%, the effect of forming a hollow beam cannot be remarkably obtained as described later. As the cathode structure of the present embodiment, either an oxide-coated cathode structure formed by coating an electron emission substance of oxide or an impregnated cathode structure formed by impregnating a porous metal with an electron emission substance can be applied.

The electron emission suppressing region can be formed by a depression (concave groove) of the electron emission body. At this time, the depth of the recessed portion is such that the electric field does not soak into the recessed portion from the electrode in the three-pole portion (cathode, first electrode, and second electrode) so that the electric field strength does not contribute to electron emission. Is set to That is, the depth is such that no electrons are emitted from the electron emission suppression region. The electron emission suppression region is
It can be formed at the cutout of the electron emitting body. For example, the electron emission main body may be entirely cut off in the thickness direction to form the electron emission suppression region.

A method of manufacturing an electron gun according to an embodiment of the present invention includes a step of performing laser processing utilizing a plasma release phenomenon on a part of an electron emission main body of a cathode structure to form an electron emission suppression region, A cathode structure adapted to emit a hollow electron beam is formed. The laser processing using the plasma release phenomenon can be performed by non-thermal processing performed by irradiating a femtosecond laser, as described above.

In the present manufacturing method, laser cutting utilizing a plasma release phenomenon can be used to form a cut portion in a so-called electron emission body having an electron emitting substance, and this cut portion can form an electron emission suppression region. For example, the electron emission main body can be entirely cut off in the thickness direction to form the electron emission suppression region. Further, by laser processing utilizing the plasma release phenomenon, a recessed portion can be formed in a so-called electron emission body having an electron emitting substance, and the electron emission suppression region can be formed by this recessed portion.

In the present manufacturing method, the cathode structure in which the electron emission body is formed and a part or all of the electron gun electrode system, for example, a part or all of the prefocus electrode system, or the prefocus electrode system and the main focus electrode system are included. It is possible to assemble all the electrodes or a part thereof and irradiate the femtosecond laser through the beam transmission holes of the electrodes to form an electron emission suppression region in the electron emission body. In this laser processing, a predetermined voltage is applied between the cathode surface of the cathode structure and the electrodes facing the cathode surface to prevent the substances released in the plasma, so-called processing scattering, from adhering to the electrodes.
It is preferable to perform the above laser processing. Alternatively, it is preferable to perform laser processing while sucking and removing a substance liberated by plasma, so-called processing scattered matter. Further, it is preferable to perform the laser processing while combining the application of these voltages and the suction removal. Further, a part or all of the provisional electron gun electrode system, for example, part or all of the prefocus electrode system, or all or part thereof including the prefocus electrode system and the main focus electrode system is assembled to the cathode structure. It is also possible to irradiate the laser through the beam transmission hole of the temporary electrode to form the electron emission suppression region, and then remove the temporary electrode to newly arrange a part or all of the true electron gun electrode system.

An important point of introducing the hollow electron beam into the electron gun is how to accurately align it with the electron gun axis. In the present invention, the beam transmission hole of the electrode, preferably the beam transmission hole G ₁ of the first electrode is used as a reference for laser processing, that is, laser irradiation is performed through the beam transmission hole of the so-called electrode for cutting.

A cathode ray tube according to the embodiment of the present invention comprises the above-mentioned electron gun. A display device according to an embodiment of the present invention is configured to include a cathode ray tube having the electron gun described above.

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

For cutting by laser irradiation, as shown in FIG. 10, depending on the energy density and the oscillation pulse width, melting, vaporization, or plasma formation (a bare state of only atomic nuclei in which electron clouds are stripped from atoms) There are three types of processing. For example, when a metal to be processed is irradiated with a laser having a wide oscillation pulse width, the irradiated region is melted (melted). When the metal to be processed is irradiated with a laser having the same energy amount and a narrow oscillation pulse width, the irradiated region is vaporized (vaporized). These melt processing and vaporization processing are thermal processing because they are accompanied by thermal vibration. When the metal to be processed is irradiated with a laser having the same energy amount and a narrower oscillation pulse width, metal atoms are turned into plasma and released. In this plasma processing, by irradiating high energy in a short time, atoms in the irradiated region are rapidly excited, and the interatomic bond is cut so that the atoms are separated from the electron cloud around the atoms,
This is a processing method that utilizes the phenomenon that atoms are released by being made into plasma. That is, very high intensity light energy is injected into the atoms in the irradiated area for an extremely short time interval, the atoms in that area are plasmatized and released, and the energy injection is performed before the surrounding atoms start thermal vibration. It is a processing method that ends. This plasma processing is non-thermal processing.

The present invention utilizes this plasma processing. In this embodiment mode, a femtosecond laser whose oscillation pulse width is 1 picosecond or less is used. As a specific example, Er
-Nd-YAG oscillation laser double wave, wavelength: 775n
m, oscillation pulse width: 0.15 picoseconds can be used.

FIG. 1 shows the structure of an electron gun according to an embodiment of the present invention, in particular, a three-pole part (a constituent part consisting of a cathode, a first electrode and a second electrode) which is a main part thereof. This example is applied to an electron gun having an impregnated cathode structure.
The electron gun 1 according to the present embodiment includes an impregnated cathode structure 2
And a first electrode (control electrode) G ₁ and a second electrode (control electrode)
G ₂ and a plurality of electrodes (not shown) each including an electrode group 3 (an electrode group forming the main electron lens system) after the third electrode G ₃ are arranged. In an electron gun for a color cathode ray tube, cathode structures 2 corresponding to red (R), green (G) and blue (B) are arranged in a line, and a first electrode G ₁ common to these three cathode structures 2 is arranged. , The second electrode G ₂ ,
・ A plurality of electrodes are arranged.

In the impregnated cathode structure 2, for example, a cylindrical sleeve 4 made of a metal such as tantalum (Ta) is joined to one end of a cup 6 made of a heat-resistant material such as tantalum (Ta) and having a U-shaped cross section. The impregnated cathode substrate (that is, the electron emission body) 7 is placed in the cup 6, and the sleeve 4
A heater 5 for heating the impregnated cathode substrate 7 is built therein. The impregnated cathode substrate 7 is a porous metal substrate, for example, a porous tungsten (W) substrate having a certain porosity obtained by sintering tungsten powder, and an electron emitting material, for example, barium carbonate BaCo ₃ and calcium carbonate. CaCo ₃ and aluminum oxide Al ₂ O ₃ are mixed, and the mixed powder is fired in a hydrogen atmosphere at a high temperature, and is uniformly impregnated with an electron-emitting substance having a predetermined particle size obtained by pulverization. It Although not shown, a thin film for reducing the work function, such as Ir, Os, Ru, Re, Sc ₂ O, is formed on the surface of the impregnated cathode substrate 7 on the electron emission side.
Coating with a high melting point metal ₃ and the like, or Sc ₂ O ₃ or the like can also be formed layer by porous sintered body containing.

In the present embodiment, in particular, at the center of the surface of the impregnated cathode substrate 7 (that is, the central portion corresponding to the beam transmission hole h ₁ of the first electrode G ₁ ), plasma conversion using a femtosecond laser is performed. A recess 8 having a predetermined depth is formed by processing, and the recess 8 forms an electron emission suppression region 9. The area viewed from the upper surface of the recess 8 is set smaller than the area of the beam transmission hole h ₁ of the first electrode G ₁ as described later. The depth d ₁ of the recess 8 is set to a depth at which the electric field strength at the recess 8 does not contribute to electron emission, for example, 40 μm or more.

Next, a method of manufacturing the electron gun 1, particularly,
An embodiment of a method of manufacturing the sword structure 2 will be described. Destination
Without the heater 5 inside the sleeve 4, as shown in FIG. 2A.
An impregnated mold whose surface is molded flat inside the cup 6
The cathode assembly 2 was assembled by accommodating the sword base 7
After that, a part or all of the prefocus electrode system, in this example, one
Part of the first electrode G ₁At a predetermined distance from the cathode assembly 2,
For example, they are arranged at intervals of about 80 μm. First electrode
G₁Beam transmission hole h₁Diameter φ₁Is 300 in this example
μm. This first electrode G₁The position of the actual electron gun
Is the same as the position that constitutes

The prefocus electrode system here refers to the electrodes excluding the cathode assembly 2. In this example, the first electrode G ₁ and the second electrode G ₂ are a prefocus electrode system. The prefocus electrode system may be slightly different in the number of electrodes depending on the definition of prefocus and the electrode structure forming the electron gun.

Next, as shown in FIG. 2B, the first electrode G ₁
The position of the beam transmission hole h ₁ of the femtosecond laser 1 is measured by using the optical lens system 13 based on the measured position.
4 is irradiated with, the femtosecond laser 14 is irradiated through the beam transmission holes h ₁ of the first electrode G _1, the surface central portion of the impregnated cathode base 7 forms the laser processing to recess 8, the recess portion The electron emission suppression region 9 is formed by 8. The opening diameter of the recessed portion 8, that is, the diameter φ ₂ of the electron emission suppression region 9 is smaller than the beam transmission hole diameter φ ₁ of the first electrode G ₁ , and can be, for example, about 50 to 200 μm.
This laser processing is performed, for example, as shown in FIG. 3A, on the surface of the impregnated cathode substrate 7, a thin film 15 for reducing the work function.
It is also possible to irradiate the laser in the state where the thin film is formed to form the recessed portion 8, or, as shown in FIG. 3B, after the laser irradiation is performed to form the recessed portion 8 before forming the thin film 15,
The thin film 15 may be deposited on the surface of the impregnated cathode substrate 7 including the inner surface of the recess 8.

In the case of the impregnated cathode structure 2, for example, the laser wavelength is 775 nm, the power is 200 μJ, and the irradiation time is 200.
With a msec and a diaphragm diameter of 2 mm, a treparing method as shown in FIG.
The electron emission suppression region 9 can be created. 16 is a laser beam. The diameter, depth, and shape of the electron emission suppression region 9 can be arbitrarily changed by this treparing method. The shape of the electron emission suppression region 9 can be arbitrarily changed according to the shape of the beam transmission hole h ₁ of the first electrode G ₁ , for example, a circle, an ellipse, a rectangle (an astigmatism), or the like. Depression 8
The control in the depth direction can be controlled by the pulse number (time) of the laser.

FIG. 11 shows a beam transmission hole h of the first electrode G _1.
6 is a graph showing the relationship between the axial deviation (μm) of the electron emission suppression region 9 with respect to ₁ and the electron beam spot diameter Vss (μm) on the screen. In the figure, the mark ■ indicates a conventional electron beam, and the mark ● indicates a hollow beam of the present invention. As shown in FIG. 11, the electron beam spot diameter starts to deteriorate when the axial deviation is 40 μm or more, but the axial deviation of the electron emission suppressing region 9 with respect to the beam transmission hole h ₁ of the first electrode G ₁ is 10 μm by the above method. It can be suppressed to the following, and the electron beam spot diameter does not deteriorate.

Incidentally, as shown in FIGS. 18A and 18B, for example, at the center of the electron emission main body 42 of the cathode assembly 41, for example, YA
After forming the electron emission suppression region 43 by G laser irradiation, mechanical cutting, mold molding, etc., the cathode structure 41 and the first electrode G
It is conceivable to assemble ₁ to a predetermined size, but this method is difficult to suppress the axial displacement of the first electrode G ₁ of the beam transmission hole h ₁ and the electron emission suppression area 43 to 10μm or less. If the axis shift is large, an electron beam spot with halation is drawn, and the electron beam spot diameter is deteriorated.

Since the laser processing of this embodiment is non-thermal processing using a femtosecond laser, that is, the oscillation pulse width is narrowed down to about 10 ^-13 seconds, and high-luminance energy is irradiated within the short time. As a result, plasma is released in the processed region instantaneously, and the process ends before the workpiece is thermally processed, which is non-thermal processing, so that the periphery of the laser irradiation part, that is, the electron emission region of the cathode is thermally processed. It can be processed with little chemical damage. In conventional processing using a carbon dioxide gas laser or a YAG laser, most of the light energy applied to the material to be processed is converted into heat energy, which causes processing by melting, decomposition, and scattering, but with femtosecond lasers, it is extremely short. Since energy is concentrated on the material to be processed over time, nanoplasma, nanoshock, breakdown, lattice distortion, and shock wave are generated at ultra-high speed, processing progresses before heat is generated, and only the irradiated area is induced. No damage to. Therefore, according to the manufacturing method of the present embodiment, when forming the recessed portion 8 that becomes the electron emission suppression region, a thermal alteration region is formed around the recessed portion 8,
It is possible to form the recessed portion 8 serving as the electron emission suppressing region stably and with high accuracy without any thermal deformation portion or the like to which the molten metal adheres like burrs.

In the electron gun 1 of the present embodiment, since the electron emission suppression region 9 is formed by the recess 8 at the center of the surface of the impregnated cathode substrate 7 of the cathode assembly 2, during operation, the electron emission suppression region 9 is removed. Does not emit electrons, and a concentric hollow beam 11 is emitted from the upper surface of the impregnated cathode substrate 7 as shown in the figure. That is, the depth d is 40 μm in the hollow portion 8 forming the electron emission suppression region 9 at the center of the cathode.
Because of the above, the electric field strength at the center of the cathode is such that the electric field strength does not contribute to electron emission, and a high current (for example, 1 m
A good hollow beam will be emitted even in the case of A or more and 2-3 mA or more). Incidentally, the central part of the cathode of the axisymmetric electron beam system has the highest electric field strength. For this reason, if the depth of the recessed portion 8 that becomes the electron emission suppression region 9 is shallow, electrons move on the cathode surface and are emitted from the electron emission suppression region 9 into the space. In our experiments, 40
The hollow beam effect could not be exhibited at a high current in the recess having a shallow depth of μm or less.

According to the present embodiment, the recessed portion 8 forming the electron emission suppressing region 9 is formed by plasma processing, that is, non-thermal processing by irradiating the femtosecond laser, so that the vicinity of the recessed portion 8 is formed. No heat-deteriorated part, burrs (projections), or other deformation due to heat (heat-deformed part) is formed at all.
Therefore, the electron emission suppression region 9 does not spread only in the region of the recessed portion 8 and unnecessary electron emission due to burrs does not occur,
Electron radiation is stabilized, and a highly accurate hollow beam can be emitted. Incidentally, when the recessed portion 8 is formed by thermal processing by ordinary laser irradiation, a heat-altered portion such as a melted area and an oxidized discolored area (for processing in the atmosphere) occurs around the recessed portion 51 (Fig. 12A). Since the thermal alteration portion does not contribute to electron emission, the electron emission suppression region is widened as a result. In addition, burrs (projections) 52 are formed around the recessed portion due to the heat generated during laser irradiation (see FIG. 12A).
Even if there is no electron emission substance, electron emission occurs from this protrusion, which causes a problem.

FIG. 12 shows the surface condition when the surface of the impregnated cathode substrate is laser processed. Normal Nd-YAG
When the electron emission suppression region of the cathode structure is processed with a laser (wavelength: 532 nm, pulse width: 0.05 msec), as shown in FIG. 12A, the heat-melted metal is projected on the end face of the processed region like burrs 52. Adhere to the shape. On the other hand, a femtosecond Er-Nd-YAG laser (wavelength: 775 nm,
When processed with a pulse width of 0.15 picoseconds, as shown in FIG. 12B, since the metal does not melt by heat, the end face of the processed region is smooth, and thermal transformation of the electron emission region does not occur.

FIG. 5 shows a battery according to another embodiment of the present invention.
Child gun, especially the three-pole part (cathode, first electrode)
And the structure of the second electrode). This example is
Applied to an electron gun with a cathode-coated cathode assembly
This is the case. The electron gun 21 according to the present embodiment is equipped with an ox
Id coating type cathode structure 22 and first electrode (control electrode)
G₁, Second electrode (control electrode) G₂, Third electric power
Pole G ₃Subsequent electrode groups 3 (constituting the main electron lens system and the like)
And a plurality of electrodes each composed of an electrode group).
Electron guns for color cathode ray tubes use red (R), green (G) and
In-line each cathode structure 22 corresponding to blue and blue (B)
Arranged and common to these three cathode assemblies 22
First electrode G₁, The second electrode G₂, ...
Placed.

In the oxide-coated cathode assembly 22, a base metal 25 made of, for example, nickel (Ni), nickel alloy, or the like is joined to the upper portion of a cylindrical sleeve 24 made of metal, and the oxide is formed on the base metal 25. Layer of electron-emitting material (ie, electron-emitting body) 2
7 is applied, and the electron emission material layer 2
A heater 26 for heating 7 is built in.
The electron emission material layer 27 is formed of, for example, barium carbonate BaC.
It is formed by applying an electron-emitting substance in which O ₃ , strontium carbonate SrCo ₃ , and calcium carbonate CaCo ₃ are mixed in a binder and heating in a vacuum to convert it into an oxide.

In the present embodiment, in particular, the center of the oxide coating type cathode assembly 22 (that is, the first electrode G ₁
In the central portion corresponding to the beam transmission hole h ₁ of), a cutout portion 28 is formed by removing all the electron emission material layers 27 in the film thickness direction by plasma processing using a femtosecond laser.
An electron emission suppression region 29 is formed by this cutout portion 28. In this example, the cutout portion 28 is formed such that the electron emission material layer 27 is entirely removed in the film thickness direction and the base metal 25 of the base is exposed. The area viewed from the upper surface of the cutout portion 28 is set smaller than the area of the beam transmission hole h ₁ of the first electrode G ₁ as described later. Electron emitting material layer 2
The film thickness d ₂ of 7 is the same as the depth of the recessed portion 8 of the impregnated cathode substrate 7 described above, so that the electric field strength at the cutout portion 28 (cathode center) does not contribute to electron emission. For example, the film thickness is set to 40 μm or more.

Next, a method of manufacturing the electron gun 21, particularly,
An embodiment of a method of manufacturing the cathode structure 22 will be described. First, as shown in FIG. 6A, an electron emission material layer 27 is formed by coating on a base metal 25 joined to a sleeve 24 so that the surface is flat, and a cathode assembly 22 having a heater 26 built in the sleeve 24. After assembling, part or all of the prefocus system electrodes, in this example, part of the first electrodes G ₁ are arranged at a predetermined distance from the cathode structure 22, for example, a distance of about 80 μm. First electrode G ₁
The diameter φ ₁ of the beam transmission hole h ₁ is 300 μm in this example.
And The position of the first electrode G ₁ is the same as the position forming the actual electron gun.

Next, as shown in FIG. 6B, the first electrode G ₁
The position of the beam transmission hole h ₁ of the femtosecond laser 1 is measured by using the optical lens system 13 based on the measured position.
4 and the femtosecond laser irradiated through the beam transmission hole h ₁ of the first electrode G ₁ is used to emit the electron emission material layer 2
The central portion of 7 is laser-processed to form a cut portion 28, and the cut portion 28 forms an electron emission suppression region 29.
The opening diameter of the cutout portion 28, that is, the diameter φ of the electron emission suppression region 9
₂ is smaller than the diameter of the beam transmission hole h ₁ of the first electrode G ₁ and can be, for example, about 50 to 200 μm.

In the case of the oxide coating type cathode structure 22, as in the case of the impregnating type cathode structure 2 described above, for example, the laser wavelength is 775 nm, the power is 200 μJ, and the irradiation time is 2.
The electron emission suppression region 29 having a diameter of 150 μm can be formed by a treparing method as shown in FIG. By this treparing method, the diameter and shape of the electron emission suppression region 29 can be arbitrarily changed. Further, as described with reference to FIG. 11, also in the oxide-coated cathode structure 22, the axial deviation of the electron emission suppression region 29 with respect to the beam transmission hole h ₁ of the first G ₁ can be suppressed to 10 μm or less by this method,
The electron beam spot diameter does not deteriorate.

Since the laser processing in the oxide-coated cathode structure 22 of the present embodiment is also non-thermal processing using a femtosecond laser, as described above, the cut portion 28 to be the electron emission suppressing region 29 is formed. At this time, a thermally altered region, a thermally deformed portion that melts and adheres like burrs, etc. does not occur at all around the excision portion 28, and the excision portion 28 serving as an electron emission suppression region is formed stably and with high accuracy. be able to. The oxide layer, which is the electron emission material layer 27, has a white color,
When the conventional laser processing is tried, there are cases where even the same energy amount is cut, and cases where it is not cut occur, and stable processing cannot be performed. The reason is that in the conventional laser processing method, light is diffusely reflected because the oxide layer is white, and is greatly affected by the reflectance of the laser irradiation region, and further, since the irradiation region is white, the absorption of laser light is poor. . In the femtosecond laser processing, since the irradiated region is processed into plasma in an instant and processed, the physical properties of the irradiated region are less likely to affect and good cutting of the white oxide layer is possible. Conventional examples of forming hollow beams have been limited to the impregnated cathode structure, but the present invention also enables the formation of an oxide-coated cathode structure.

According to the electron gun 21 of the present embodiment, the excision portion 28 forming the electron emission suppression region 29 of the oxide coating type cathode structure 22 is formed by plasma processing by femtosecond laser irradiation, that is, non-thermal processing. Since it is formed, a thermally altered portion and a burr (protrusion) are formed in the vicinity of the cut portion 28.
Deformation due to heat such as (thermal deformation part) is not formed at all. Therefore, the electron emission suppression region 29 does not spread only in the region of the cutout portion 28, unnecessary electron emission due to burrs does not occur, and the electron emission is stabilized and a precise hollow beam can be emitted.

As described above, the electron guns 1 and 21 of the present embodiment are large in the broadband era in which the electron beam spot diameter is not enlarged at the time of a large cathode current and high brightness and high resolution are required. It is suitable for application to an electron gun for a screen cathode ray tube.

In the above example, in the laser processing, the cathode structure and some or all of the electrodes constituting the prefocus electrode system are assembled and the femtosecond laser is irradiated onto the electron emission body through the beam transmission hole. Other,
For example, the cathode structure and all the electrodes including the prefocus electrode system and the main focus electrode system can be assembled, and the femtosecond laser can be applied to the electron emission body through the beam transmission hole to form the electron emission suppression region.

In the impregnated cathode structure 2 and the oxide-coated cathode structure 22 of the above example, the depth of the recessed portion 8 and the depth of the cut portion 28 (film thickness of the electron emission material layer 27)
Was set to a value at which the electric field strength was such that it did not contribute to electron emission.
Even if the cutout portion 28 is formed, the depth of the recessed portion 8 and the cutout portion 28 are reduced, and the recessed portion 8 and the cutout portion 28 are covered with, for example, an insulating material or another layer that does not emit electrons, thereby forming a cathode structure. Can also be formed. However, in this case,
The number of steps is increased, and the reliability is inferior to that of the above embodiment.

On the other hand, a femtosecond laser is used to emit electrons.
When processing the suppression areas 9 and 29, do not remove processing scatterers.
However, laser processing is desirable. For example oxide
In the coating type cathode structure 22, an object to be processed is
The quiside turns into plasma at ultra-high speed and immediately becomes oxide.
Returning to that, the oxide is the first electrode G as processing scattered matter.
₁To prevent unwanted electron emission.
Need to do so. By the way, as shown in FIGS.
In the case of processing by irradiating the YAG laser 45 on the
The processing scattered matter 46 generated by irradiation is the first electrode G.₁of
Beam transmission hole h ₁Unnecessary electron emission attached to the surrounding area e^-Occurs
It is possible to do it.

The present invention provides a method of manufacturing an electron gun which suppresses such a defect and has higher reliability. Figure 7
This is one embodiment. In the present embodiment, in processing the electron emission body 27 using a femtosecond laser, a positive potential, for example, 0V to + 10V is applied to the first electrode G ₁ with respect to the cathode, and a negative potential is applied to the cathode side. For example, laser processing is performed while applying a voltage of about 0 V to −10 V to form an electric field near the processed portion. According to the laser processing of the present embodiment, since the processed flying material is turned into plasma and is positively charged, it repels the first electrode G ₁ having a positive potential and adheres the processed flying material to the first electrode G ₁ . Can be prevented, and generation of unnecessary electron emission can be prevented. On the contrary, the processed scattered material is attached to the cathode electron emission body side. This is preferable because the electron emission material is increased.

FIG. 8 shows another embodiment. In the present embodiment, in processing the electron emission body 27 using the femtosecond laser, an electrode, in this example, the first electrode G is used.
₁ and the optical lens system 13 (and also the laser irradiation source side if necessary) are made airtight, and the scattered workpiece is laser-treated while being sucked from above the beam transmission hole h ₁ of the first electrode G ₁ and removed to the outside. To do. According to the laser processing of the present embodiment, it is possible to prevent the processing scattered particles from adhering to the first electrode G ₁ and the base metal 25, and to prevent generation of unnecessary electron emission. If the voltage application method of FIG. 7 and the suction method of FIG. 8 are combined, the effect is further enhanced.

Although not shown, another embodiment will be explained.
Reveal One of the temporary pre-focus electrode system that becomes a dummy
Prepare all or part. Preferably the temporary first electrode G₁
Only prepare. Then, in advance, the
Part or all of the sword structure and the temporary prefocus electrode system
Part, in this example, the provisional first electrode G ₁And assemble. Provisional first
1 electrode G₁Beam transmission hole h₁The position of
Irradiate femtosecond laser based on the measurement result,
1 electrode G₁Beam transmission hole h₁The light emitted through
The electron emission body is laser-processed with a mutosecond laser
A child radiation suppression region is formed. Then, this temporary first electrode
G₁Remove the temporary first electrode G₁True to the same position as
1 electrode G₁The prefocus electrode system so that
Assemble. According to this embodiment,
Assemble part or all of the prefocus electrode system of
Laser processing, then remove this temporary electrode and
Since the refocus electrode system is assembled, it is possible to
Even if the processed scattered material adheres to the temporary electrode, the
With the sub-gun, the scattered material is not attached,
Occurrence can be prevented.

The above-mentioned measure for preventing the processing scattered particles from adhering to the electrode (the method of FIGS. 7 and 8 and the method of using the temporary electrode) can be applied to both the oxide coating type and the impregnating type.

FIG. 15 shows an embodiment of a cathode ray tube equipped with the electron gun according to the present invention described above. In the color cathode-ray tube 31 according to the present embodiment, the color fluorescent screen 34 is formed on the inner surface of the panel 32P of the tubular body 32.
4, the color selection mechanism 35 is arranged to face each other, and the neck portion 32
The electron gun 36 of the present invention [for example, the electron gun 1 or 21 described above] is arranged in N. Neck part 32N of tube 32
The electron beam B _R ,
Deflection yoke 3 for deflecting B _G and B _B horizontally and vertically
7 is placed. According to such a color cathode ray tube 31,
By providing the electron gun 36, the electron beam spot system does not become large at the time of a large cathode current, and high brightness,
High resolution images are obtained.

The electron gun 36 of the present invention [for example,
Child gun 1 or 21] is, for example, a 3-gun type electron gun, compound
It can be applied to single electron guns. 16 gun type
A representative example of an electron gun is shown. Electron gun 361 of the present embodiment
Is the three corresponding to red, green and blue arranged inline
The cathode K [K_R, K _G, K_B] Is common
, A plurality of electrodes, that is, the first electrode G₁, The second electrode
G₂, Third electrode G₃, The fourth electrode G_Four, Fifth electrode G_Five, First
6 electrodes G₆Are arranged in this order. Sixth electrode G₆of
In the latter part, the shield cup G that is integrated with you₇Is provided
It Sixth electrode G₆Is supplied with a high voltage potential (anode voltage)
To be done. Fifth electrode G_FiveAnd the third electrode G₃Are connected to each other
The focus voltage Fs is supplied. Fourth electrode G_FourAnd the
2 electrodes G₂Are connected to each other and are supplied with a low voltage. First
Electrode G₁Is supplied with 0V. Fifth electrode G_FiveAnd 6th electrode
G₆A main electron lens is formed therebetween.

FIG. 17 shows a typical example of a double beam single electron gun.
You The electron gun 362 of this embodiment has an in-line arrangement.
Three cathodes K [K_R，
K_G, K_B], A plurality of electrodes,
That is, the first electrode G₁, The second electrode G₂, Third electrode G₃, 4th
Electrode G_FourAnd the fifth electrode G_FiveAre arranged in sequence and the fifth electrode
G_Five4 electrostatic deflection plates P in the subsequent stage₁, P₂, P₃, P_Four
The electrostatic convergence means C consisting of is arranged.
Fifth electrode G_FiveAnd the third electrode G₃The anode voltage HV is supplied to
And the fourth electrode G_FourFocus voltage Vf is supplied to
Third electrode G₃, The fourth electrode G_FourAnd the fifth electrode G_FiveMain train
A child lens is formed. Inner electrostatic deflector P₂And P₃To
Is supplied with the anode voltage HV, and the outer electrostatic deflection plate P₁Over
And P_FourHas a convergence voltage lower than the anode voltage
Supplied. The operation of this electron gun 362 is as follows.
It Cathode K_R, K_G, K_BThree electrons emitted from
Beam B_R, B_G, B_BCross with the main electron lens,
Rear center beam B_GIs the electrostatic deflection plate P₂And P₃Straight between
Go ahead, both side beams B_R, B _BEach is an electrostatic deflection plate P₃
And P_FourAnd the electrostatic deflection plate P₁And P₂Inward between
It is deflected and converges on the phosphor screen.

The present invention is used as a display device such as a television receiver, a computer display, or a projection-type display device cormorant, etc. by incorporating a color cathode ray tube equipped with the above-mentioned electron gun, a monochromatic cathode ray tube or a black and white cathode ray tube into a set. Can be configured. According to such a display device, since the electron gun is provided, the electron beam spot system does not become large at the time of a large cathode current, and a display image with high brightness and high resolution can be obtained.

The advantages of applying the hollow beam to the cathode ray tube and the display device are the following four points. 1) Repulsion between electrons in the electron beam is reduced. In the usual structure, the current density near the beam axis is high, and the repulsion between the electrons increases the diameter of the electron beam bundle before reaching the fluorescent surface from the cathode surface. In the case of a donut-shaped hollow beam, since there is no high current density portion in the center of the beam, repulsion between the electrons is reduced, and the electron beam spot diameter can be reduced because the electron beam spot can be converged smaller on the phosphor screen.

That is, three electrodes (cathode K, first electrode G ₁
And when the cathode current is controlled by the arrangement of the second electrode G ₂ ), a crossover is formed between the cathode K and the first electrode G ₁ . This crossover becomes the object point of the main electron lens system. The diameter and divergence angle of the crossover seen from the main electron lens system are greatly related to the electron beam diameter on the phosphor screen. If the electron beam spot diameter on the phosphor screen is φ, then Equation 1 holds.

[0063]

[Formula 1] φ = M · φc + M · Cs · θ ³ + Rep. Here, M: image magnification of main electron lens system, Cs: spherical aberration of main electron lens system φc: crossover diameter seen from main electron lens system θ: divergence angle seen from main electron lens system Rep: repulsion between flying electrons effect

The electrons emitted from the cathode surface crossover at a point farther from the cathode as the electrons are emitted from the cathode surface closer to the electron beam axis, and the crossover diameter seen from the main electron lens system is near the electron beam axis. Determined by electron orbit. Therefore, by forming a hollow electron beam bundle, the crossover diameter can be reduced, and the electron beam spot diameter on the phosphor screen can be made smaller than in the formula 1.

2) The influence of spherical aberration of the main lens can be reduced. The focus position is deviated between the electron trajectory at the center of the electron beam and the electron trajectory at the outermost portion of the electron beam due to spherical aberration of the main electron lens system of the electron gun. The focus position is closer to the electron gun as the outer part of the electron beam is closer. In the case of a hollow beam, since there is no electron orbit passing through the center of the electron beam, the difference in focal position is smaller, the electron beam can be converged smaller than in the conventional electron gun, and the electron beam spot diameter on the fluorescent screen can be reduced. 3) It is hard to receive ion damage. Since the electron emitting material is not arranged on the portion of the cathode surface where the electric field strength is the strongest, it is difficult to receive the attack of positive ions generated in a vacuum. This means that resistance to cathode current slumping and damage to the cathode due to abnormal discharge is improved. 4) The drive characteristics at high cathode current are improved. When driving a conventional electron gun with a high cathode current, near the center axis of the electron beam on the cathode surface, the state is almost close to the saturation current density, and the electron emission from this part in the high current region is caused by the change in the cathode drive voltage. Is less sensitive to. In the case of a hollow beam, there is no supply of electrons from this portion, and the electron emission is from the wider cathode region that does not reach the saturation current density, so the drive characteristics are improved in the high current region.

FIG. 13 shows that the cathode current is 1000 μA.
First electrode G₁Beam transmission hole h ₁Electron for area
Area ratio of radiation suppression region and beam spot of hollow beam
It is a graph which shows the relationship with a diameter. Small electron emission suppression area
Finally, from the above Equation 1, the cross as seen from the main electron lens system.
The over diameter is large, and the electron beam can be sufficiently focused.
I can't come. On the contrary, if the electron emission suppression area is large,
The divergence angle seen from the main electron lens system becomes larger than 1
Therefore, it is strongly affected by lens aberrations and halation is reduced.
Electron beam spot, and the electron beam spot diameter is
It doesn't get smaller. Therefore, the electrons as shown in FIG.
The area ratio of the radiation suppression region has an optimum value. This graph
According to the first electrode G₁For the beam transmission hole area of
The area ratio of the child radiation suppression region may be 5% to 45%.
If this value is exceeded, the effect of forming a hollow beam becomes remarkable.
I can't get it. In the example of FIG. 13, the area of the electron emission suppression region
It can be said that it is desirable to set the rate to about 25%.

FIG. 14 is a graph showing the cathode current Ik-electron beam spot diameter Vss characteristics at the center of the screen when the present invention is applied to a 21-inch monitor cathode ray tube. The electron emission suppression region was set to 25%. In the figure,
A curve (dotted line) A is the characteristic of the conventional electron gun shown for comparison, and a curve (B) is the characteristic of the hollow beam electron gun of the present invention. As is clear from the curve B, the effect of the hollow beam begins to be effective near the cathode current of 0.3 mA, and the electron beam spot diameter Vss becomes smaller than the conventional current as the current increases. The electron beam spot diameter Vss is 13% at a cathode current of 0.5 mA and 23 at 0.7 mA.
% And 27% at 1.0 mA.

[0068]

According to the electron gun of the present invention, the electron emission suppressing region in the cathode structure is formed with high accuracy, and the heat-altered portion and the heat-deformed portion are not formed around the region, so that electron emission is stable, It is possible to emit an optimum hollow electron beam without unnecessary electron emission or deterioration of the beam diameter. When there is an electron emission suppression region processed by a laser having an oscillation pulse width of 1 picosecond or less, it becomes an electron emission suppression region by non-thermal processing, and an optimum hollow electron beam can be emitted. When the area of the electron emission suppression region is set to 5% to 45% of the beam transmission hole area of the first electrode, the effect of the hollow electron beam is remarkably obtained, and the fine beam spot diameter can be obtained.

When the electron emission suppressing region is formed at the cutout portion of the electron emission body, the optimum hollow electron beam can be emitted with a simple structure. When the electron emission suppression region is formed by the recessed portion of the electron emission main body and the depth of the recessed portion is set to a depth at which the electric field strength does not contribute to electron emission,
An optimal hollow electron beam can be emitted with a simple structure. Therefore, if the electron gun of the present invention is applied to a cathode ray tube and a display device, a fine beam spot can be obtained even at a large current, and high brightness and high resolution of an image can be achieved.

According to the electron gun manufacturing method of the present invention,
Since a part of the electron emission main body of the cathode structure is subjected to laser processing utilizing the plasma release phenomenon to form the electron emission suppression region, it is possible to easily form the electron emission suppression region with high accuracy. Therefore, it is possible to manufacture an optimum hollow beam electron gun with stable electron emission and without unnecessary electron emission or deterioration of the beam diameter. When a laser having an oscillation pulse width of 1 picosecond or less is used as this processing laser, non-thermal processing becomes possible, and the electron emission suppression region can be formed with high accuracy. When the ablation portion is formed in the electron emission body by the non-thermal processing by the laser and the electron emission suppressing region is formed by the ablation portion, the manufacturing becomes simple and mass production becomes possible. When the recessed portion is formed in the electron emission body by the non-thermal processing by the laser and the electron emission suppression region is formed by the recessed portion, the manufacturing is simplified and mass production is possible. The present method can be applied to both the impregnated negative cathode structure and the oxide-coated cathode structure.

When the cathode assembly on which the electron emission body is formed and a part or the whole of the electron gun electrode system are assembled and laser irradiation is performed through the beam transmission hole of the electrode to form the electron emission suppression region, the axial deviation is generated. It is possible to form an electron emission suppression region with high accuracy and without or extremely small suppression. In advance, the cathode structure and a part or all of the temporary electron gun electrode system are assembled, laser irradiation is performed to form an electron emission suppression region, and then the temporary electrode system is removed, and a true electron gun electrode is placed at the same position. When assembling part or all of the system,
It is possible to avoid the influence of processing scattered matter on the electrodes. When laser processing is performed while applying a voltage between the electrodes facing the cathode surface of the cathode structure to prevent the deposition of the processing debris, the influence of the processing debris on the electrodes can be avoided. When performing laser processing while suction-removing the processed flying material, the influence of the processed flying material on the electrode can be avoided.

According to the cathode ray tube of the present invention, it is possible to obtain an image of high brightness and high resolution by including the electron gun. According to the display device of the present invention, by including the cathode ray tube, it is possible to obtain a display image with high brightness and high resolution. The present invention can provide a cathode ray tube and a display device suitable for the broadband age, for example.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a main part showing an embodiment of an electron gun according to the present invention.

2A to 2B are process diagrams showing an embodiment of a method for manufacturing the electron gun of FIG.

3 is a sectional view showing an example of the cathode assembly obtained in FIG. 2B. FIG. 3 is a sectional view showing another example of the cathode assembly obtained in FIG.

FIG. 4 is an explanatory diagram showing an example of forming an electron emission suppression region by a treparing method.

FIG. 5 is a configuration diagram of a main part showing another embodiment of the electron gun according to the present invention.

6A to 6B are process diagrams showing an embodiment of a method of manufacturing the electron gun of FIGS.

FIG. 7 is a process drawing showing another embodiment of the method for manufacturing an electron gun of the present invention.

FIG. 8 is a process drawing showing another embodiment of the electron gun manufacturing method of the present invention.

FIG. 9 is an explanatory diagram of a cathode assembly that emits a hollow beam.

FIG. 10 is an explanatory diagram showing a processing phenomenon of laser processing based on an oscillation pulse width and energy density.

FIG. 11 is a graph showing the relationship between the axis deviation and the beam spot diameter during processing of the electron emission suppression region of the present invention.

FIG. 12 is a state diagram showing a state of a cathode surface by A conventional laser processing. B is a state diagram showing a state of the cathode surface by laser processing of the present invention. FIG.

FIG. 13 is a graph showing the relationship between the cathode current and the beam spot diameter when comparing the hollow beam electron gun of the present invention with a conventional electron gun.

FIG. 14 is a graph showing the relationship between the area ratio of the electron emission suppression region and the beam spot diameter with respect to the beam transmission hole area of the first electrode.

FIG. 15 is a configuration diagram showing an embodiment of a cathode ray tube according to the present invention.

FIG. 16 is a configuration diagram showing an example of an electrode structure of an electron gun according to the present invention.

FIG. 17 is a configuration diagram showing another example of the electrode structure of the electron gun according to the present invention.

FIG. 18 is a process chart showing the problems of the comparative example of the method for manufacturing the A to B electron guns.

FIG. 19 is a process chart showing the problems of the comparative example of the method for manufacturing the A to B electron guns.

[Explanation of symbols]

1, 21 ... Electron gun, 2, 22 ... Cathode structure,
3 ... Electrode group, 4, 24 ... Sleeve, 5, 26 ...
..Heaters, 6 ... Cups, 28 ... Excisions, 14
... Femtosecond laser, 7, 27 ... Electron emission main body, 8 ... Recessed portion, 9,29 ... Electron emission suppression region, 31 ... Cathode ray tube, 32 ... Tube, 34 ...
Fluorescent screen, 35 ... Color selection mechanism, 36 ... Electron gun, 3
7 ... deflection yoke, G ₁ ~G ₆ ... electrode, K
[K _R, K _G, K _B] .. cathode

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yoshida Yamada             6-735 Kita-Shinagawa, Shinagawa-ku, Tokyo Soni             -Inside the corporation F term (reference) 5C027 CC01                 5C031 DD09 DD15 DD19                 5C041 AA03 AB03

Claims (26)

[Claims] 1. An electron emission suppressing region formed by laser processing utilizing a plasma liberation phenomenon, wherein a thermal alteration portion and / or a thermal deformation portion due to the laser processing is not provided around the electron emission suppressing region. An electron gun comprising a cathode structure adapted to emit a hollow electron beam and a plurality of electrodes. 2. A cathode assembly having an electron emission suppression region which is non-thermally processed by a laser having an oscillation pulse width of 1 picosecond or less, and which emits a hollow electron beam, and a plurality of electrodes. An electron gun characterized by that. 3. An electron emission suppressing region is provided at the center of the electron emission main body, and the area of the electron emission suppressing region is set to 5% to 45% of the area of the beam transmission hole of the first electrode, and a hollow electron is formed. An electron gun comprising a cathode structure adapted to emit a beam and a plurality of electrodes. 4. The electron gun according to claim 1, 2 or 3, wherein the cathode structure is an oxide coating type or an impregnating type. 5. The electron emission suppressing region is formed by a cutout portion of an electron emission body.
The electron gun according to 2, 3, or 4. 6. The electron emission suppressing region is formed by a recessed portion of the electron emission body, and the depth of the recessed portion is set to a depth at which the electric field strength does not contribute to electron emission. The electron gun according to claim 1, 2, 3, or 4. 7. A cathode configured to emit a hollow electron beam, including a step of forming an electron emission suppression region by performing laser processing utilizing a plasma release phenomenon on a part of an electron emission main body of a cathode structure. A method of manufacturing an electron gun, which comprises forming a structure. 8. The method of manufacturing an electron gun according to claim 7, wherein a laser having an oscillation pulse width of 1 picosecond or less is used as the processing laser utilizing the plasma release phenomenon. 9. The method of manufacturing an electron gun according to claim 7, wherein a cutout portion is formed in the electron emission body by the laser processing, and the electron emission suppression region is formed by the cutout portion. 10. The method of manufacturing an electron gun according to claim 7, wherein a recess is formed in the electron emission main body by the laser processing, and the electron emission suppression region is formed by the recess. 11. A cathode assembly having an electron emission body formed therein and part or all of an electron gun electrode system are assembled, and the laser is irradiated through a beam transmission hole of the electrode,
The method for manufacturing an electron gun according to claim 7, 8, 9 or 10, wherein an electron emission suppression region is formed in the electron emission body. 12. A cathode assembly having an electron emission body formed in advance and part or all of a temporary electron gun electrode system are assembled, and the laser is irradiated through a beam transmission hole of the temporary electrode to emit the electron. 9. After forming the electron emission suppressing region in the main body, the temporary electrode is removed, and a part or all of the true electron gun electrode system is assembled at the same position as the temporary electrode. The method of manufacturing an electron gun according to item 9 or 10. 13. The laser processing is performed while applying a voltage between the cathode surface of the cathode structure and the electrode facing the cathode surface to prevent the plasma liberated substance from adhering to the electrode. Claim 11 or 12
A method of manufacturing the described electron gun. 14. The laser processing is performed while suction-removing a plasma liberated substance.
13. The method for manufacturing an electron gun according to 1 or 12. 15. An electron emission suppressing region formed by including laser processing utilizing a plasma liberation phenomenon, wherein there is no thermal alteration portion and / or thermal deformation portion due to the laser processing around the electron emission suppressing area. A cathode ray tube comprising a cathode structure for emitting a hollow electron beam, and an electron gun comprising a plurality of electrodes. 16. A cathode assembly having an electron emission suppressing region that is non-thermally processed by a laser having an oscillation pulse width of 1 picosecond or less, and configured to emit a hollow electron beam, and a plurality of electrodes. A cathode ray tube comprising an electron gun. 17. An electron emission suppressing region is provided in the center of the electron emission main body, and the area of the electron emission suppressing region is set to 5% to 45% of the area of the beam transmission hole of the first electrode, and a hollow electron is formed. A cathode ray tube comprising an electron gun composed of a cathode structure for emitting a beam and a plurality of electrodes. 18. The cathode structure of the electron gun is an oxide coating type or an impregnating type.
The cathode ray tube according to 5, 16, or 17. 19. The electron emission suppressing region of the cathode structure of the electron gun is formed by a cutout portion of an electron emission body.
The described cathode ray tube. 20. The electron emission suppression region of the cathode structure of the electron gun is formed by a recessed portion of the electron emission body, and the depth of the recessed portion is such that the electric field strength does not contribute to electron emission. 19. The cathode ray tube according to claim 15, 16, 17 or 18, wherein the cathode ray tube is set. 21. An electron emission suppressing region formed by including laser processing utilizing a plasma liberation phenomenon, wherein there is no heat-altered portion or / and thermal deformation portion due to the laser processing around the electron emission suppressing region. A display device comprising: a cathode structure for emitting a hollow electron beam; and a cathode ray tube having an electron gun including a plurality of electrodes. 22. A cathode assembly having an electron emission suppressing region that is non-thermally processed by a laser having an oscillation pulse width of 1 picosecond or less, and configured to emit a hollow electron beam, and a plurality of electrodes. A display device comprising a cathode ray tube having an electron gun. 23. An electron emission suppression region is provided in the center of the electron emission main body, and the area of the electron emission suppression region is set to 5% to 45% of the area of the beam transmission hole of the first electrode, and a hollow electron is formed. A display device comprising a cathode ray tube having an electron gun including a cathode structure for emitting a beam and a plurality of electrodes. 24. The display device according to claim 21, 22 or 23, wherein the cathode structure of the electron gun comprises a cathode ray tube of an oxide coating type or an impregnation type. 25. The electron emission suppressing region of the cathode structure of the electron gun comprises a cathode ray tube formed by a cutout portion of the electron emitting body.
The display device according to 2, 23 or 24. 26. The electron emission suppression region of the cathode structure of the electron gun is formed by a recessed portion of the electron emission body, and the depth of the recessed portion is such that the electric field strength is such that it does not contribute to electron emission. 25. The display device according to claim 21, 22, 23 or 24, comprising a set cathode ray tube.