JP2002025421A - Electron-gun and its manufacturing method, and color cathode-ray tube and color picture tube using the electron gun - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electron gun, which emits electrons effectively by making up a structure which includes an emitter emitting thermoelectrons, in a stable manner at low temperatures. SOLUTION: With the electron gun being provided with an emitter, a cap/ sleeve with a heater built in the inside, and a plurality of grid electrodes, an emitter can be obtained which can easily emit thermoelectrons, by arranging so that the emitter contains at least diamond on the cap.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electron gun having an emitter that emits thermoelectrons by heating and a method of manufacturing the same, and more particularly to an electron gun having a diamond as an emitter. Further, the present invention relates to a color picture tube and a color picture receiving system, which comprise the above-mentioned electron gun and emit a phosphor by irradiation with an electron beam.

[0002]

2. Description of the Related Art A color picture tube used as a CRT is a typical phosphor light emitting device that emits a phosphor by irradiation with an electron beam. In this method, an image is displayed by deflecting and scanning an electron beam emitted from a single electron gun and causing a phosphor at an arbitrary position to emit light. 2. Description of the Related Art A color picture tube is the most widespread image display device in the world, and has an advantage that a high quality image can be provided at a low price. However, since the electron beam is deflected, there is a problem that the electron beam spreads elliptically in the peripheral portion of the phosphor screen as shown in FIG. 3, and the resolution is lower in the peripheral portion than in the central portion. With the start of digital broadcasting, high-definition video distribution is scheduled, and a color picture tube capable of displaying high-definition video over the entire screen is desired. As a means for realizing this, a method of reducing the electron beam diameter by reducing the amount of current of the electron beam can be considered. This technique is
XGA has already been adopted for monitors such as personal computers.
(Resolution: 1024 x 768) or S-XGA (resolution: 1280 x 1)
024) has been realized. However, since the current amount of the electron beam is reduced, the brightness is reduced, and it is not possible to directly adapt to the image display in which brightness is an important image quality factor. As the start of digital broadcasting approaches, it is strongly desired to realize a color picture tube capable of realizing high-definition video display without lowering luminance. That is, there is an urgent need to develop an electron gun capable of deflecting and scanning a high-density electron beam with a small diameter. To realize this, an emitter material that can realize a high emission current density is indispensable.

Conventionally, in an electron gun most commonly used in a color picture tube, barium / barium is used as an emitter material.
Barium oxide / strontium oxide (Ba.Sr) O obtained by decomposing and synthesizing strontium carbonate (BaCO ₃ / SrCO ₃ ) by heat treatment is used. (Ba ・ S
r) The O emitter is called an oxide cathode, and has the advantages of a simple manufacturing process, excellent productivity, and low cost. However, since (Ba.Sr) O is a semiconductor and has a large electric resistance, when emission of a large current is taken out, Joule heat is generated and the temperature of the emitter rises, so that Ba is excessively evaporated and the life is shortened. Therefore, high-current emission was difficult.

As another emitter, there is an emitter called an I cathode. In the I cathode, a pellet made of porous tungsten is impregnated with (BaO + CaO + Al ₂ O ₃ ), and an Os—Ru alloy thin film is formed on the electron emission surface of the pellet. The I cathode is operated by heating to about 1000 ° C., at which time the impregnated BaO is reduced by tungsten to form free Ba. Free Ba thermally diffuses through the vacancies and forms a Ba + monoatomic layer on the electron emission surface. Electrons are formed by the electric dipole formed by the positive charge of this Ba + monoatomic layer and the negative charge inside the metal. Due to the attractive force, it easily jumps out into a vacuum. The I-cathode has the advantage that Joule heat is hardly generated because the pellet is made of metal, and stable high-current emission operation is possible. On the other hand,
A high-temperature operation is required, and there has been a problem that the service life is shortened due to thermal deformation and thermal damage of the heater. As mentioned above,
The conventional electron gun has a problem that when the current density of the emission is increased, the lifetime is shortened due to a rise in the temperature of the emitter, the heater is deformed, and the like, and it is difficult to operate stably for a long time.

In the conventional electron gun, it is difficult to reduce the electron beam diameter without reducing the amount of current due to its structure. FIG. 4 shows a cross section of the electron gun. In FIG.
Is an emitter, 31 is a first grid electrode, 32 is a second grid electrode, and 37 is an electron transmission hole through which electrons pass in the first grid. An electron beam is emitted from the emitter 30 heated by the heater 35 according to the electric field intensity distribution determined by the first grid electrode 31, the second grid electrode 32, and the emitter 30. Normally, the first grid 31 is at ground potential and the second grid electrode 32
Is applied with a positive potential (fixed potential), and the emitter 30 is applied with a negative potential. The current amount of the electron beam is adjusted by changing the potential applied to the emitter 30 as necessary. That is, when increasing the amount of current, the emitter (negative) potential is set large, and when decreasing the amount of current, the emitter potential is decreased. When the emitter potential is large, the electron beam is radiated as shown in FIG. 5A, and compared with when the emitter potential is small as shown in FIG. Is done. As a result, the electron beam diameter becomes large at the time of a large current, and it is difficult to increase the definition of the color picture tube. In addition, since the position of the object point changes when the current is small and when the current is large, the size of the emitter operating area 36 changes. It is difficult to achieve optimal convergence.
This is one factor in increasing the diameter of the electron beam, which is making it difficult to achieve high definition.

[0006] In order to solve the above-mentioned problems of the prior art, the present invention provides an efficient configuration by arranging diamond such as diamond particles or aggregates of diamond particles on an emitter as an electron emission source. By realizing an electron gun that can stably emit large current electron beams and reduce the electron beam without reducing the amount of current,
An object of the present invention is to provide a color picture tube realizing a high-definition image.

Further, the method of the present invention includes a step of disposing diamond particles on a cap or an emitter base material, thereby producing an electron gun having an emitter capable of easily emitting a phosphor as a component. The aim is to provide a method that can.

Further, the method of the present invention provides an important manufacturing process for manufacturing a high-efficiency color picture tube provided with the electron gun, and a method for easily and rationally controlling the surface state of diamond. With the goal.

[0009]

According to an aspect of the present invention, there is provided an electron gun including an emitter, a cap / sleeve provided with a heater therein, and a plurality of grid electrodes, which are arranged coaxially. The emitter includes at least diamond and is disposed on the cap.

According to the present invention, in the electron gun, the diamond contained in the emitter is a diamond particle or an aggregate of diamond particles, and the average particle size is preferably 0.2 μm or less. Further, the carbon atoms on the outermost surface of the diamond particles or the diamond particle aggregate preferably have a structure terminated by bonding with hydrogen atoms.

Further, according to the present invention, in the above-mentioned electron gun, the diamond contained in the emitter may be in the form of a film, and in this case, carbon atoms on the outermost surface of the film-like diamond are terminated by bonding with hydrogen atoms. It is characterized by including.

According to the present invention, there is provided the electron gun, wherein at least diamond is contained, and the region of the emitter disposed on the cap is an electron transmission hole of a first grid electrode disposed adjacent to the emitter among the grid electrodes. Is not exceeded.

According to another aspect of the present invention, there is provided an electron gun including an emitter, a cap / sleeve provided with a heater therein, and a plurality of grid electrodes coaxially. Characterized in that at least diamond is disposed on the quality emitter substrate, and the emitter substrate on which the diamond is disposed is disposed on the cap / sleeve.

According to the present invention, in the above-mentioned electron gun, the diamond disposed on the emitter substrate is preferably a diamond particle or an aggregate of diamond particles, and the average particle size is preferably 0.2 μm or less. Further, the present invention is characterized in that the carbon atoms on the outermost surface of the diamond particles or the aggregates of the diamond particles arranged on the emitter substrate include a structure terminated by bonding with hydrogen atoms.

Further, according to the present invention, in the above-mentioned electron gun, the size of the emitter in which at least diamond is arranged on the porous emitter base material is equal to the electron transmission of the first grid electrode arranged adjacent to the emitter among the grid electrodes. It is characterized by not exceeding the hole.

According to another aspect of the present invention, there is provided a method for manufacturing an electron gun including an emitter substrate on which at least diamond particles or aggregates of diamond particles are arranged. And a step of bonding a hydrogen atom to a carbon atom on the outermost surface of the diamond particles or the aggregate of diamond particles.

According to another aspect of the present invention, there is provided a method of manufacturing an electron gun including an emitter substrate on which at least diamond particles or aggregates of diamond particles are disposed. Distributing the aggregates of the diamond particles or the step of growing diamond on the surface of the aggregates of the diamond particles; and the step of growing diamond on the outermost surface of the diamond layer or the diamond layer grown on the aggregates of the diamond particles. The method includes a step of bonding a hydrogen atom.

In order to achieve the above object, a method for manufacturing an electron gun having an emitter containing film diamond at least on the surface or surface thereof according to the present invention comprises the steps of: forming a film diamond on an emitter substrate; A step of bonding a hydrogen atom to a carbon atom on the outermost surface of the film-shaped diamond.

The present invention also provides the method for manufacturing an electron gun, wherein the step of forming the film-like diamond includes the step of distributing diamond particles or agglomerates of diamond particles; The method includes a step of growing a diamond layer on the aggregate.

Further, in the method of manufacturing an electron gun according to the present invention, the step of distributing diamond particles or aggregates of diamond particles on the emitter substrate is to apply a solution in which diamond particles are dispersed to the emitter. It is characterized by the following.

According to the present invention, in the method for producing an electron gun, the step of distributing diamond particles or agglomerates of diamond particles on the emitter substrate includes disposing the emitter substrate in a solution in which diamond particles are dispersed. And applying ultrasonic vibration to the solution.

Further, in the method for manufacturing an electron gun according to the present invention, the step of distributing diamond particles or agglomerates of diamond particles in the emitter substrate may include disposing the emitter substrate in a solution in which diamond particles are dispersed. Between the conductive portion of the emitter substrate and the container containing the solution,
Alternatively, a voltage is applied between the conductive portion of the emitter substrate and an electrode provided in a solution.

According to the present invention, in the method for producing an electron gun, the step of bonding a hydrogen atom to a carbon atom on the outermost surface of the diamond particle or the aggregate of the diamond particle includes disposing a particulate diamond on an emitter substrate. rear,
The method further includes a step of exposing the emitter base material to plasma obtained by discharge-decomposing a gas containing at least hydrogen, or a step of heating the emitter base material in a gas containing at least hydrogen.

According to another aspect of the present invention, there is provided a color picture tube according to the present invention, comprising: a panel portion on which a phosphor screen is formed;
It has a neck portion with an electron gun mounted inside and a funnel portion integrated with the panel portion, and the electron gun is any of the electron guns described in the present invention.

According to another aspect of the present invention, there is provided a color picture tube according to the present invention, comprising: a panel portion on which a phosphor screen is formed;
A color picture tube having a neck portion with an electron gun mounted therein and a funnel portion integrated with the panel portion, wherein the electron gun is the electron gun of the present invention, and the color picture tube is Is characterized in that hydrogen gas is sealed.

The present invention is also characterized in that in the color picture tube structure, hydrogen gas is sealed inside.
At this time, the pressure inside the color picture tube is preferably higher than 10 ⁻² Pa.

In order to achieve the above object, a color image receiving system according to the present invention comprises at least a color picture tube of the present invention, an audio speaker, a video signal tuner, a drive circuit / signal processing circuit, and a cabinet. It is characterized by having.

According to the electron gun of the present invention, the following effects can be obtained by a configuration in which diamond such as diamond particles or aggregates of diamond particles is arranged on the emitter as the electron emission source.

FIG. 1 is an example of a sectional view showing a basic structure of an electron gun according to the first configuration of the present invention. As shown in FIG. 1, the electron gun of the present invention is arranged on the same axis as an emitter 1 and a cap 2, a sleeve 3, a heater 4, a first grid electrode 5, and a second grid electrode 6 as main components. And a plurality of grid electrodes. Here, the emitter 1 has a configuration in which diamond particles or aggregates of diamond particles are arranged, or diamond particles or aggregates of diamond particles are arranged on a porous emitter substrate.

When the emitter 1 is heated by the heater 4 in the same manner as in the prior art, thermions are emitted.
In contrast to the necessity of heating at a temperature of not less than ° C., in the configuration of the present invention, thermoelectrons are easily emitted by the action of diamond particles or aggregates of diamond particles, and thermoelectrons are more stably emitted at a lower temperature. .

In a structure in which diamond particles are arranged on a porous emitter substrate, more effective effects can be obtained. This is because the emitter substrate is porous and has a large surface area, so that more diamond particles can be arranged.

In the apparatus configuration of the present invention, the average particle diameter of the diamond particles disposed on the emitter substrate is 0.2 μm or less, and more preferably, the average diameter of the diamond particles is:
According to a preferred example of a thickness of 0.05 μm or less, it is possible to arrange an extremely large number of diamond particles that facilitate the emission of thermoelectrons. That is, the distribution density of diamond particles or agglomerates of diamond particles can be arranged at a high density of at least 1 × 10 ¹⁰ or more per square centimeter on the cap 2 and the emitter substrate, so that large thermionic emission can be easily achieved. Can be obtained.

In the device configuration of the present invention, diamond is very suitable as an electron-emitting material such as a wide bandgap semiconductor (5.5 eV), high hardness, abrasion resistance, high thermal conductivity, and chemical inertness. Since it has properties, it becomes possible to realize an electron gun having an emitter capable of stably emitting thermoelectrons at a low heating temperature.

Further, in the device configuration of the present invention, a structure in which the carbon atoms on the outermost surface of the diamond disposed on the cap and the emitter substrate are terminated by bonding with hydrogen atoms, more preferably, the carbon atoms on the outermost surface of the diamond According to a preferred example including a structure in which the amount of bonded hydrogen is 2 × 10 ¹⁵ atoms / cm ² or more, the surface of the hydrogen-terminated diamond has a negative electron affinity state, and thus emits very electrons. It can be made easy to do.

Further, according to the method of the present invention, the method includes the step of distributing diamond particles to the cap and the emitter base material, so that the following effects can be obtained.

In other words, diamond which facilitates thermionic emission can be arranged in the form of fine particles or aggregates thereof on the cap or the emitter base material with good reproducibility, so that a stable and highly efficient emitter can be easily formed. It is possible to do. As a result, an efficient electron gun can be easily formed.

Further, if a structure in which a diamond layer is grown by using the arranged fine diamond particles as a nucleus, further excellent electron emission characteristics can be obtained. A sufficient effect can be obtained by setting the average particle diameter of the diamond particles to be 0.2 μm or less, but the smaller the better, the better. The average particle diameter is desirably 0.05 μm or less.

In the method of the present invention, the method of distributing diamond particles to the cap or the emitter substrate may be such that a solution in which diamond particles having an average particle diameter of 0.2 μm or less are dispersed is applied to the cap or the emitter substrate. Alternatively, a cap or an emitter base is placed in a solution in which particulate diamond having an average particle size of 0.2 μm or less is dispersed, and ultrasonic vibration is applied to the solution, or the conductive part of the cap or the emitter base and the solution are applied. According to a preferred example of applying a voltage between the container placed therein, or between the conductive portion of the cap or the emitter substrate and the electrode provided in the solution, a cap of any shape such as a linear or plate shape, The diamond particles can be distributed uniformly and with good controllability and reproducibility even on the emitter substrate. In addition, it is possible to select a dispersion region of diamond particles.

At this time, the amount of the diamond particles dispersed in the solution to be used is 0.04 per liter of the solution.
The amount is 1 g or more and 100 g or less, and more preferably 0.1 g or more and 20 g or less per liter of the solution. The specific optimum amount of diamond particles depends on the average particle size of the diamond particles used, and is approximately 1 g when the particle size is 0.01 μm and approximately 16 g when the particle size is 0.04 μm. In such a solution, about 1 × 10 ¹⁶ to 1 × 10 ²⁰ diamond particles are dispersed per liter of the solution, so that a sufficient number of fine diamond particles can be easily distributed on the emitter substrate. It is possible. As a dispersion medium for the solution to be used, a solution containing water or alcohol as a main component is mainly used for ease of handling.

In the structure of the emitter of the electron gun of the present invention, it is very important to control the surface of the arranged diamond particles. This is because thermionic emission characteristics change depending on the surface state of diamond. The method for optimizing the surface structure of diamond particles is not particularly limited, but it is easy to control the elements that bond to carbon atoms on the diamond surface. In the present invention, as a specific example, a diamond can be made into a state where thermal electrons can be easily emitted by using a hydrogen-terminated surface. By arbitrarily controlling such surface state changes,
The configuration and manufacturing process of the high-efficiency electron gun can be simplified.

Therefore, according to the configuration of the present invention, after the diamond particles are arranged on the cap or the emitter substrate, the cap or the emitter substrate is exposed to plasma obtained by discharge-decomposing at least a gas containing hydrogen. Alternatively, since the cap or the emitter substrate is characterized by having a step of heating in a gas containing at least hydrogen, it is possible to selectively bond hydrogen atoms to carbon atoms on the outermost layer of diamond particles, As a result, it is possible to easily form a region in a state where thermoelectrons are easily emitted.

As described above, by arbitrarily controlling the surface state of the diamond disposed on the cap or the emitter substrate, the configuration and the manufacturing process of the high-efficiency electron gun can be simplified.

Also, in the electron gun of the present invention, the region where the diamond is arranged does not exceed the electron transmission hole 7 of the first grid electrode 5 which is arranged adjacent to the emitter among the grid electrodes. Thus, an electron gun with a small change in the electron beam diameter regardless of the magnitude of the electron beam current can be realized. Therefore, by using the electron gun of the present invention, a high-definition color picture tube or color picture receiving system can be realized without lowering the luminance.

[0044]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described more specifically with reference to examples.

<First Embodiment> FIG. 1 schematically shows a first embodiment of the electron gun of the present invention. In FIG. 1, 1 is an emitter (diameter 0.2 mm) in which diamond particles are dispersed and arranged on a porous emitter substrate, 2 is a cap for supporting the emitter, 3 is a sleeve in which a heater is provided, and 4 is an insulating coating on the surface. Heater. Reference numeral 5 denotes a first grid electrode, and electron transmission holes 7 provided in the first grid electrode 5.
Has a diameter of about 0.5 mm and is larger than the emitter 1.

First, an emitter substrate is prepared. The material used for the emitter substrate is not particularly limited, but a sintered substrate of tungsten was used in this example. Next, after the emitter substrate was cleaned in a normal washing step, the surface was coated with the fine diamond particles by infiltrating into a solution in which fine diamond particles having an average particle size of 0.02 μm were dispersed. . In this embodiment, a solution in which 0.4 g of diamond particles is dispersed in 1 liter of pure water is used. That is, a solution containing approximately 2 × 10 ¹⁷ diamond particles per liter of solution was used. After the application of the diamond particles, the emitter substrate is dried by irradiation with infrared lamp light.

When the surface of the emitter substrate obtained by the above-described method was observed with a scanning electron microscope, it was confirmed that minute diamond particles were scattered and distributed. Its distribution density was about 5 × 10 ¹⁰ pieces / cm ² .

The emitter 1 on which the fine diamond particles are arranged is placed in a vacuum higher than 10 ^-5 Pa, and is heated by energizing the heater 4. As a result, thermoelectrons are emitted in a temperature range of about 400 ° C. It was confirmed that.

On the other hand, in a conventional electron gun having (Ba.Sr) O as an emitter (in this case, the region coated with (Ba.Sr) O is larger than the electron transmission hole 7 of the first grid electrode 5), Heating at 780 ° C. or higher was required to obtain the same thermionic emission. That is, it was confirmed that the emitter 1 on which the fine diamond particles were arranged functions as an efficient thermoelectron emission source.

When the characteristics were evaluated by installing an electron gun in a color picture tube (32-inch wide), the electron beam diameter in the peripheral portion of the phosphor screen in the conventional electron gun was equal to the average drawing time (current 1 mA / gun). Is about 3 mm and about 5.5 mm at the time of peak drawing (current 4 mA / gun), while about 1.0 mm at the time of average drawing (current 1 mA / gun) in the electron gun of the present invention.
5mm, about 2.5 at peak drawing (current 4mA / gun)
mm, and it was confirmed that the electron beam was narrowed.

In this embodiment, when the type of the emitter substrate is changed to another material, for example, tantalum (Ta), or when the shape or size of the emitter substrate is changed, or when the particle size or the diameter of the diamond particles to be applied is changed. When the solution was prepared by changing the amount, similar results were obtained even when an alcohol such as ethanol was used as the solvent.

In a configuration in which diamond particles or diamond particles are directly disposed on the cap of an electron gun without using an emitter substrate, the current amount is slightly reduced, but the current amount is almost twice as large as that of a conventional emitter. Was confirmed.
The reason for the decrease in the amount of current is that the cap 2 is not porous, so the surface area is small, and the arrangement density of diamond particles is reduced by about one digit.

<Second Embodiment> Similar to the first embodiment, fine diamond grains are arranged on a tungsten emitter base material having a diameter of 0.2 mm, and a diamond layer is further grown using the diamond grains as nuclei. The result of this case will be described. At this time, the diameter of the electron transmission hole of the first grid electrode is 0.5 mm.

The emitter substrate used and the method of arranging the fine diamond particles on the emitter substrate are the same as in the first embodiment. In the present embodiment, the emitter substrate is infiltrated into the dispersion solution of the fine diamond particles, the fine diamond particles are applied to the surface, and then a diamond layer is formed on the diamond particles distributed on the surface of the emitter substrate. The method for synthesizing the diamond layer is not particularly limited, but is often used because the vapor phase synthesis method is easy. The vapor phase synthesis method generally uses methane, ethane, ethylene, hydrocarbon gas such as acetylene, alcohol, an organic compound such as acetone, and a carbon source such as carbon monoxide diluted with hydrogen in a raw material gas, This is performed by decomposing the raw material gas. At that time, oxygen or the like may be further added to the raw material gas. Although there is no particular limitation on the applicable gas phase synthesis method, microwave plasma CVD is used in this embodiment.
A diamond layer was formed by the method. The microwave plasma CVD method is a method of forming a diamond by applying a microwave to a source gas to form diamond. As specific conditions, a carbon monoxide gas diluted to about 1 to 10 vol% with hydrogen was used as a source gas. Reaction temperature and pressure are 800-900 ° C respectively
And 25 to 40 Torr (1 Torr = 133.322 Pa).
A formation time of about 1 to 5 minutes is sufficient.

As a result of forming a CVD diamond layer on the fine diamond particles on the emitter substrate by the above method, the surface of the fine diamond particles arranged by coating was coated with a good quality CVD diamond layer. The surface state of the obtained diamond particles was a state terminated by hydrogen.

The emitter substrate on which the diamond particles prepared in such a procedure were arranged was placed in a vacuum of 1 × 10 ⁻⁵ Pa or more, and heated by a heater. Was confirmed to have been released.
The same current can be emitted even when the temperature of the emitter is lower by about 50 ° C. to 100 ° C. as compared with the case where diamond particles are simply dispersed. Also, the surface of the hydrogen-terminated CVD diamond layer is very stable,
It has been confirmed that the device has stable thermoelectron emission characteristics even in an environment with a relatively low degree of vacuum (about 1 × 10 ^-2 Pa). That is, it was confirmed that the emitter on which the fine diamond particles were arranged functions as an efficient thermoelectron emission source.

Then, when an electron gun was installed in a color picture tube (32 type wide) and its characteristics were evaluated, it was found that the electron beam was converged as compared with the conventional electron gun as in the first embodiment. It could be confirmed. Specifically, on the phosphor screen, the electron beam diameter at the peripheral portion of the screen is the average drawing time (current 1 mA / current).
About 1.3 mm at the time of peak drawing (current 4 mA /
Gun) was about 2 mm.

In the present invention, the diamond on the surface of the emitter substrate is not limited to the form of particles or agglomerates thereof, but may be formed by growing a CVD diamond layer on fine diamond particles further to form diamond-like aggregates. However, the effect of the present invention is not at all hindered.

In this embodiment, substantially the same result can be obtained even in a configuration in which diamond particles or aggregates of diamond particles are directly provided on the cap of the electron gun without using the emitter substrate.

It is preferable that at least hydrogen gas is sealed in the color picture tube in the order of 10 ^-2 Pa. Thereby, the hydrogen-terminated form on the outermost surface of the diamond particles can be stably maintained for a longer time. By encapsulating hydrogen, the lifetime (time until the amount of emitted electrons is reduced by half) could be extended to about 40,000 hours. Without hydrogen, the life is about 25,000 hours.

<Third Embodiment> Next, a description will be given of a result when ultrasonic vibration is used as a method of arranging fine diamond particles on the emitter substrate.

The emitter base material and the like used are the same as in the first embodiment. In the present embodiment, the cleaned emitter substrate is placed in a container containing a solution in which fine diamond particles having an average particle size of about 0.02 μm are dispersed, and ultrasonic vibration is applied to the entire container ( Hereinafter, this is referred to as “ultrasonic vibration treatment” to distribute the fine diamond particles on the emitter substrate. In this embodiment, a solution in which 0.4 g of diamond particles is dispersed in 1 liter of pure water is used. The power applied during the ultrasonic vibration processing is about 100 W, and the processing time is 5 to 15 minutes. The emitter substrate subjected to the ultrasonic vibration treatment was washed in pure water, and then dried by blowing with nitrogen gas.

When the surface of the emitter substrate subjected to the ultrasonic vibration treatment was observed with a scanning electron microscope, it was found that the fine diamond particles dispersed in the solution were uniformly distributed. The distribution density was about 1 × 10 ¹¹ / cm ² . By the ultrasonic vibration treatment, the diamond particles can be dispersed and arranged at a higher density than in the case of the drop coating.

The emitter substrate on which the diamond particles produced by such a method are arranged is placed in a high vacuum of 10 ⁻⁵ Pa or more, and heated by a heater. It was confirmed that thermoelectrons were emitted from the emitter substrate on which was disposed. That is, it was confirmed that the emitter on which the fine diamond particles were disposed was acting as an efficient thermoelectron emission source. The emitted current is larger than when the diamond particles are provided by the coating method. This is due to the high density of the diamond particles provided.

When the characteristics were evaluated by installing an electron gun in a color picture tube (32 type wide), it was found that the electron beam was converged as compared with the conventional electron gun, as in the first embodiment. It could be confirmed. Specifically, on the phosphor screen, the electron beam diameter at the peripheral portion of the screen is the average drawing time (current 1 mA / current).
About 1.4 mm at the time of peak drawing (current 4 mA /
Gun) was about 2.4 mm. However, the required driving voltage of the electron gun is 4 times that of the coating method of 80 V, which is about half.
5 V, and low-voltage driving is possible.

In the present embodiment, the same applies to the case where the type of the cathode material is changed to another material, for example, tantalum (Ta), or the case where the solution is prepared by changing the diameter and amount of diamond particles to be applied. Was obtained.

In this embodiment, substantially the same result can be obtained even if the diamond particles or the aggregates of the diamond particles are directly provided on the cap of the electron gun without using the emitter substrate.

<Fourth Embodiment> Subsequently, as a method of arranging the fine diamond particles on the emitter base material, a result in a case where a diamond layer is formed on the fine diamond particles after performing an ultrasonic vibration treatment. Is described.

The emitter substrate used and the method of distributing the fine diamond particles on the emitter substrate are the same as in the third embodiment. The method for forming the diamond layer is the same as in the second embodiment.

As a result of forming the diamond layer on the fine diamond particles by the above-described method, the surface of the fine diamond particles arranged by the ultrasonic treatment has a high quality C.
Coated with a VD diamond layer. The surface state of the diamond particles was a state terminated by hydrogen.

The emitter substrate on which the diamond particles produced by such a method are arranged is placed in a high vacuum of 10 ⁻⁵ Pa or more and heated by a heater. As a result, thermoelectrons are generated in a temperature range of about 300 ° C. The release was confirmed. Further, since the surface of the hydrogen-terminated CVD diamond layer is very stable, the environment (1 × 10 ⁻² Pa
(Degree), it was confirmed to have stable thermoelectron emission characteristics. That is, it was confirmed that the emitter on which the fine diamond particles were arranged functions as an efficient thermoelectron emission source. Compared to the case without hydrogen termination,
The same current can be emitted even if the temperature of the emitter is about 50 ° C. to 100 ° C. lower. The emitted current is larger than when the diamond particles are provided by the coating method. This is due to the high density of the diamond particles provided.

When the characteristics were evaluated by installing an electron gun on a color picture tube (32 type wide), it was found that the electron beam was converged as compared with the conventional electron gun, as in the first embodiment. It could be confirmed. Specifically, on the phosphor screen, the electron beam diameter at the peripheral portion of the screen is the average drawing time (current 1 mA / current).
About 1.3 mm at the time of peak drawing (current 4 mA /
Gun) was about 5 mm. At this time, the emitter temperature was about 300 ° C., and the driving voltage was about 40 V.

In the present embodiment, even when the type of the emitter base material is changed to another material, for example, tantalum (Ta), or when the solution is prepared by changing the diameter and amount of the diamond particles to be applied, Similar results were obtained.

In this embodiment, substantially the same result can be obtained even in a configuration in which diamond particles or aggregates of diamond particles are directly disposed on the cap of the electron gun without using the emitter substrate.

In the present invention, the diamond on the surface of the emitter substrate is not limited to the form of particles or agglomerates thereof. Even in the form, the effects of the present invention are not impaired at all.

It is preferable that at least hydrogen gas is sealed in the color picture tube in the order of 10 ⁻² Pa. Thereby, the hydrogen-terminated form on the outermost surface of the diamond particles can be stably maintained for a longer time. By encapsulating hydrogen, the life (time until the amount of electron emission is reduced by half) is about 4
Can be extended to 10,000 hours. Without hydrogen, the life is about 25,000 hours.

<Fifth Embodiment> Next, an emitter substrate is provided in a solution in which fine diamond particles are dispersed, and a voltage is applied between the emitter substrate and an electrode provided in the solution to apply a voltage to the emitter substrate. The result of arranging the fine diamond particles on the substrate will be described.

The emitter substrate used is the same as in the above embodiment. Subsequently, the emitter substrate and the platinum plate electrode are placed in a container containing a solution in which fine diamond particles having an average particle size of about 0.02 μm are dispersed, and a DC voltage is applied between the emitter substrate and the platinum electrode. (Hereinafter, referred to as “voltage application process”), thereby distributing the fine diamond particles to the W line. In this embodiment, a solution in which 0.4 g of fine diamond particles are dispersed in 1 liter of pure water is used. The conditions for the voltage application process are as follows: the platinum electrode side is the negative electrode, the emitter side is the positive electrode, and a voltage of 50 V
Min. The emitter substrate subjected to the voltage application treatment was washed with pure water and dried by blowing with nitrogen gas.

When the surface of the emitter substrate subjected to the voltage application treatment was observed with a scanning electron microscope, it was found that fine diamond particles were uniformly distributed on the surface of the emitter substrate that had been impregnated with the solution. Further, the distribution density was about 3 × 10 ¹⁰ / cm ² . This is presumably because the colloidal fine diamond particles in the solution had a negative charge and were attracted to the emitter substrate by the voltage application treatment.

The emitter on which the fine diamond particles produced by such a method were arranged was placed in a high vacuum of 10 ⁻⁵ Pa or more, and heated by a heater. As a result, about 400 ° C. was obtained similarly to the third embodiment. It was confirmed that thermoelectrons were emitted in the temperature range of. That is, it was confirmed that the emitter substrate on which the fine diamond particles were arranged functions as an efficient thermoelectron emission source.

When the characteristics were evaluated by installing an electron gun in a color picture tube (32 type wide), it was found that the electron beam was converged as compared with the conventional electron gun, as in the first embodiment. It could be confirmed. Specifically, on the phosphor screen, the electron beam diameter at the peripheral portion of the screen is the average drawing time (current 1 mA / current).
Gun) about 1.5mm, peak drawing (current 4mA /
Gun) was about 2.5 mm. At this time, the emitter temperature was about 400 ° C., and the driving voltage was about 80 V.

In the present embodiment, when the type of the cathode material is changed to another material, for example, tantalum (Ta), or when the solution is prepared by changing the diameter and amount of diamond particles to be applied, a platinum electrode is used. Similar results were obtained when a conductive container was used as the negative electrode.

In this embodiment, substantially the same result can be obtained even if the diamond particles or the aggregates of the diamond particles are directly disposed on the cap of the electron gun without using the emitter substrate.

<Sixth Embodiment> Next, a description will be given of the result when a voltage application process is performed as a method of distributing fine diamond particles on the emitter base material, and then a diamond layer is formed on the fine diamond particles. .

The emitter base material used, the amount of fine diamond particles dispersed in the solution used for the voltage application treatment, and the like are the same as in the fifth embodiment. Also, the method of forming the diamond layer is the same as in the third embodiment.

As a result of forming the diamond layer on the fine diamond particles by the above-described method, the surface of the diamond particles arranged by the voltage application process has good quality CVD.
Coated with a diamond layer. The surface state of the diamond particles was a state terminated by hydrogen.

The emitter substrate on which the diamond particles produced by such a method were arranged was placed in a high vacuum of 1 × 10 ⁻⁵ Pa or more, and heated by a heater. It was confirmed that electrons were being emitted. Further, since the surface of the hydrogen-terminated CVD diamond layer is very stable, the environment (1 × 10 ⁻² Pa
(Degree), it was confirmed to have stable thermoelectron emission characteristics. That is, it was confirmed that the emitter substrate on which the diamond particles were arranged functions as an efficient thermoelectron emission source.

When the characteristics were evaluated by installing an electron gun in a color picture tube (32 type wide), it was found that the electron beam was converged as compared with the conventional electron gun as in the first embodiment. It could be confirmed. Specifically, on the phosphor screen, the electron beam diameter at the peripheral portion of the screen is the average drawing time (current 1 mA / current).
Gun) about 1.5mm, peak drawing (current 4mA /
Gun) was about 2.5 mm.

In the present embodiment, the same applies to the case where the type of the cathode material is changed to another material, for example, tantalum (Ta), or the case where the solution is prepared by changing the particle size or amount of diamond particles to be applied. Was obtained. At this time, the emitter temperature was about 300 ° C., and the driving voltage was about 80 V.

In this embodiment, substantially the same result can be obtained even in a configuration in which diamond particles or aggregates of diamond particles are directly provided on the cap of the electron gun without using the emitter substrate.

It is preferable that at least hydrogen gas is sealed in the color picture tube in the order of 10 ^-2 Pa. Thereby, the hydrogen-terminated form on the outermost surface of the diamond particles can be stably maintained for a longer time. By encapsulating hydrogen, the life (time until the amount of electron emission is reduced by half) is about 4
Can be extended to 10,000 hours. Without hydrogen, the life is about 25,000 hours.

<Seventh Embodiment> As a method for controlling the surface structure of diamond particles disposed on the surface of an emitter substrate, which is a thermionic emission source, the emitter substrate is converted into a plasma obtained by discharge decomposition of hydrogen gas. The result of the exposure is described.

First, an emitter substrate having fine diamond particles disposed on its surface was prepared by the method described above. Examination of the surface state of the arranged diamond particles revealed that the diamond particles had a surface partially terminated with oxygen. Thus, the emitter substrate was exposed to ECR discharge plasma of hydrogen gas. The hydrogen plasma irradiation time at that time is 20 seconds. As a result, it was confirmed that the outermost surface carbon in the region exposed to the hydrogen plasma was changed into a bond with hydrogen, and it was found that thermionic emission characteristics were improved. That is, it was confirmed that the surface state of the diamond particles could be controlled by using this process.

When the time of exposing the hydrogen gas to the ECR discharge plasma is changed, or when the hydrogen gas is
Similar results were obtained when diluted to such an extent and when exposed to hydrogen plasma formed by another method.

<Eighth Embodiment> As a method for controlling the surface structure of diamond particles disposed on the surface of an emitter substrate, which is a thermionic emission source, the result of heating the emitter substrate in hydrogen gas will be described.

First, an emitter substrate having fine diamond particles disposed on its surface was prepared by the method described above. Examination of the surface state of the arranged diamond particles revealed that the diamond particles had a surface partially terminated with oxygen. So, we set up an emitter substrate in which micro diamond particles were placed in a cylindrical container with flowing hydrogen gas.
Heated to 600 ° C. The processing time at that time is 10
Minutes. As a result, it was confirmed that the surface carbon of the diamond particles heated in the hydrogen atmosphere was changed into a bond with hydrogen, and it was found that the thermoelectron emission characteristics of the emitter substrate were improved. That is, it was confirmed that the surface state of the diamond particles could be controlled by using this process.

When the hydrogen gas flowing into the container is diluted to about 10% with argon or nitrogen, or when the heating temperature is 400 to 90
Similar results were obtained when the temperature was changed in the range of 0 ° C.

<Ninth Embodiment> A ninth embodiment is described as follows.
The present invention relates to a color picture tube having the electron gun of the present invention. FIG. 2 shows an outline of the present embodiment. Reference numeral 20 denotes a panel portion having phosphors 21 arranged in a pattern on an inner surface thereof, and reference numeral 22 denotes a funnel portion having a neck portion 23. The panel portion and the funnel portion are joined to each other and the inside thereof is kept at a vacuum. An electron gun 24 of the present invention is disposed inside the neck portion 23. An electron beam emitted from the electron gun 24 deflects and scans the phosphor 21 to display an image.

As a result of evaluating the characteristics of a 32-inch wide color picture tube having this configuration, the electron beam diameter at the periphery of the phosphor screen was about 1.3 mm to 1.3 mm at the time of average luminance drawing (current 1 mA / gun). 5 mm, when drawing peak luminance (current 4 m
A / gun) was about 2.0 mm to 2.5 mm. At this time, the heating temperature of the emitter is 300 ° C to 400 ° C,
The drive current was between 45V and 80V.

On the other hand, in a color picture tube in which only the electron gun is replaced with a conventional electron gun with the same configuration, about 3 mm is obtained at the time of average luminance drawing (current 1 mA / gun) and at the time of peak luminance drawing (current 4 mA / gun). Was about 5.5 mm. The heating temperature of the emitter is 780 ° C. and the driving voltage is 80 V
１６０160V.

As described above, the color picture tube provided with the electron gun of the present invention can make the electron beam diameter smaller than the conventional color picture tube provided with the electron gun.
High-definition drawing can be realized without lowering the luminance.
Furthermore, since low-voltage driving can be performed at a low heating temperature, long life and low power consumption can be realized.

It is preferable that the inside of the color picture tube is filled with hydrogen gas under a vacuum higher than 1 × 10 ^-2 Pa. By filling hydrogen gas, there is variation,
On average, the luminance half life can be extended to about 35,000 hours.

<Tenth Embodiment> A tenth embodiment will be described.
At least a color picture tube described in the ninth embodiment;
The present invention relates to a color image receiving system including an audio speaker, a video signal tuner, a driving circuit / signal processing circuit, and a cabinet.

With this configuration, a long life and high reliability can be achieved.
A high-definition color image receiving system with low power consumption can be realized.

[0105]

As described above, according to the electron gun of the present invention, at least the emitter including the emitter, the cap / sleeve having the heater inside, and the plurality of grid electrodes are provided coaxially. Since the emitter contains diamond, highly efficient and stable electron emission is possible. In addition, by making the diamond surface hydrogen-terminated, more efficient and stable electron emission becomes possible.

In the electron gun having the above structure, the region where the emitter is provided does not exceed the electron transmission hole of the first grid electrode of the grid electrode which is arranged adjacent to the emitter. Thus, an electron gun having a small electron beam diameter and a small change in the electron beam diameter with a small current and a large current can be provided. As a result, it is possible to realize a color picture tube or a color picture receiving system capable of displaying a high-definition image by using the electron gun.

The method for manufacturing an electron gun according to the present invention is characterized in that the method further comprises a step of distributing diamond particles having an average particle diameter of 0.2 μm or less on the surface of the emitter base material or the cap, or on the surface layer. Therefore, diamond that facilitates thermionic emission can be arranged in the form of fine particles or agglomerates on the cathode surface or surface layer with good reproducibility. As a result, an efficient electron gun can be easily manufactured. Can be formed.

According to the electron gun of the present invention, after the diamond particles or the aggregates of the diamond particles are arranged on the surface of the cap or the emitter substrate, the gas containing at least hydrogen is discharged through the gap or the emitter substrate. A step of exposing to a plasma obtained by decomposition, or a step of heating the emitter substrate in a gas containing at least hydrogen, so that hydrogen atoms are selectively bonded to the outermost surface carbon atoms of diamond. As a result, it is possible to form an electron gun having a cathode portion that easily emits thermoelectrons.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a basic structure of an electron gun according to the present invention.

FIG. 2 is a sectional view showing a basic structure of a color picture tube according to the present invention.

FIG. 3 is a plan view showing a state of an electron beam diameter on a phosphor screen according to the present invention.

FIG. 4 is a sectional view showing a basic structure of a conventional electron gun.

FIG. 5 is a sectional view showing a basic state of electron beam operation according to a conventional electron gun.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Emitter 2 Cap 3 Sleeve 4 Heater 5 1st grid electrode 6 2nd grid electrode 7 Leader electrode 8 Electron transmission hole

Continued on the front page (51) Int.Cl. ⁷ Identification FI FI Theme Court II (Reference) // H04N 9/16 H04N 9/16 (72) Inventor Koji Akiyama 1006 Kazuma, Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. F term (reference) 5C027 CC01 CC11 5C031 DD04 DD09 DD15 5C060 BC01 CA10

Claims (23)

[Claims] 1. An electron gun having an emitter, a cap having a heater therein, a sleeve, and a plurality of grid electrodes coaxially, wherein the emitter includes at least diamond and is disposed on the cap. An electron gun, characterized in that: 2. The electron gun according to claim 1, wherein the diamond contained in the emitter is diamond particles or aggregates of diamond particles. 3. The electron gun according to claim 2, wherein the outermost carbon atoms of the diamond particles or the aggregates of the diamond particles contained in the emitter have a structure terminated by bonding to hydrogen atoms. . 4. The diamond particles have an average particle size of 0.2 μm.
The electron gun according to claim 2, wherein m is not more than m. 5. The diamond contained in the emitter is in the form of a film, and carbon atoms on the outermost surface of the film-like diamond are
2. The electron gun according to claim 1, comprising a structure terminated by a bond with a hydrogen atom. 6. An emitter region including at least diamond and disposed on the cap does not exceed an electron transmission hole of a first grid electrode of the grid electrode disposed adjacent to the emitter. Item 2. The electron gun according to Item 1. 7. An electron gun having an emitter, a cap having a heater therein, a sleeve, and a plurality of grid electrodes coaxially, wherein the emitter comprises a porous emitter substrate and at least diamond. An electron gun, wherein the emitter base on which the diamond is disposed is disposed on the cap and the sleeve. 8. The electron gun according to claim 7, wherein the diamond disposed on the porous emitter substrate is a diamond particle or an aggregate of diamond particles. 9. The method according to claim 7, wherein the outermost surface carbon atoms of the diamond particles or the aggregates of the diamond particles disposed on the emitter substrate include a structure terminated by bonding to hydrogen atoms. Electron gun. 10. The diamond particles having an average particle size of 0.2
10. The electron gun according to claim 8, wherein the diameter of the electron gun is not more than μm. 11. The size of an emitter in which at least diamond is arranged on a porous emitter base material does not exceed an electron transmission hole of a first grid electrode arranged adjacent to the emitter among the grid electrodes. The electron gun according to claim 7. 12. A method for producing an electron gun comprising an emitter provided with at least diamond particles or aggregates of diamond particles, the method comprising: distributing diamond particles or aggregates of diamond particles to the emitter; A method for manufacturing an electron gun, comprising a step of bonding a hydrogen atom to a carbon atom on the outermost surface of an aggregate of particles. 13. A method for producing an electron gun comprising an emitter on which at least diamond particles or aggregates of diamond particles are arranged, the method comprising: distributing diamond particles or aggregates of diamond particles to an emitter; A step of growing diamond on the surface of the aggregate of diamond particles; and a step of bonding hydrogen atoms to carbon atoms on the outermost surface of the diamond particles or the diamond layer grown on the aggregate of diamond particles. Manufacturing method of electron gun. 14. A method for manufacturing an electron gun provided with an emitter containing at least film diamond, comprising: forming a film diamond on an emitter substrate; and forming a hydrogen atom on the outermost carbon atom of the film diamond. And a method of manufacturing an electron gun. 15. The step of forming a film-like diamond,
The electron gun according to claim 14, further comprising: distributing diamond particles or aggregates of diamond particles; and growing a diamond layer on the distributed diamond particles or aggregates of diamond particles. Production method. 16. The method according to claim 12, wherein the step of distributing the diamond particles or the aggregates of the diamond particles on the emitter substrate is to apply a solution in which the diamond particles are dispersed to the emitter. ,
15. The method for manufacturing an electron gun according to any one of 15). 17. The step of distributing diamond particles or agglomerates of diamond particles on an emitter substrate comprises disposing the emitter substrate in a solution in which diamond particles are dispersed, and applying ultrasonic vibration to the solution. The method for manufacturing an electron gun according to any one of claims 12, 13, 14, and 15, wherein 18. The step of distributing diamond particles or aggregates of diamond particles on an emitter substrate comprises disposing an emitter in a solution in which diamond particles are dispersed,
A voltage is applied between the conductive portion of the emitter substrate and a container containing a solution or between the conductive portion of the emitter substrate and an electrode disposed in the solution.
16. The method for manufacturing an electron gun according to any one of items 4 and 15. 19. The step of bonding a hydrogen atom to a carbon atom on the outermost surface of a diamond particle or an aggregate of diamond particles comprises disposing a particulate diamond on an emitter substrate, and then, after disposing the emitter substrate, a gas containing at least hydrogen. 12. The method according to claim 12, further comprising the step of: exposing the substrate to a plasma obtained by subjecting the emitter substrate to a discharge decomposition; or heating the emitter substrate in a gas containing at least hydrogen.
4. The method for manufacturing an electron gun according to any one of 4). 20. A color picture tube comprising: a panel portion on which a phosphor screen is formed; a neck portion having an electron gun mounted therein; and a funnel portion integrated with the panel portion. A color picture tube, comprising: the electron gun according to claim 1. 21. A color picture tube comprising: a panel portion on which a phosphor screen is formed; a neck portion having an electron gun mounted therein; and a funnel portion integrated with the panel portion. A color picture tube, wherein the gun is the electron gun according to any one of claims 1 to 11, wherein the color picture tube is filled with hydrogen gas. 22. The pressure inside a color picture tube filled with hydrogen gas is higher than 10 ⁻² Pa.
2. The color picture tube according to 1. 23. A color picture system comprising at least a color picture tube, an audio speaker, a video signal tuner, a driving circuit / signal processing circuit, and a cabinet, wherein the color picture tube is provided. 20. A color image receiving system as set forth in 20.