JPH10233179A - Cathode-ray tube and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the causes of image disturbance such as deterioration of inner electronic parts, changes in focus, and convergence drift by restraining the creeping discharge of an insulating material around an electron gun. SOLUTION: A conductive film 25 is formed over the area of the interior wall surface of a neck part 13 opposite to the space between first and second grids G1, G2 where electron leakage is concentrated. The conductive film is made of a conductive material, e.g. a metal such as titanium, chromium, and nickel, or a conductive oxide film such as indium oxide, and the thickness of the film at its thinnest part that can be viewed is about one-tenth to one-third its thickest part (e.g. d1 =100nm, d2 =20nm), so that the film has a gentle thickness gradient. After a panel part 11 and a funnel part 12 are fused together by frit glass, the film is formed by a sputtering device during a process before an electron gun 16 is attached to the neck part.

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 irradiating a phosphor screen with an electron beam from an electron gun provided in a neck portion of a funnel, and more particularly to a cathode ray tube generated around an electron gun. The present invention relates to a cathode ray tube provided with a conductive film for preventing creeping discharge and a method for manufacturing the same.

[0002]

2. Description of the Related Art In general, a cathode ray tube (CRT) of a color television has a panel portion on which a phosphor screen is formed and a funnel portion integrated with the panel portion. Is elongated and has a neck. An electron gun for irradiating an electron beam on the fluorescent screen is provided on the neck portion. In this electron gun, a plurality of high-voltage and low-voltage electrodes (grids) are arranged in front of a hot cathode structure having three cathodes for red, green and blue, and each electrode emits from the hot cathode structure. The control, acceleration and focusing of the electron beam to be performed are performed.

In such a cathode ray tube, an electron around the electron gun is insulated by electrons accelerated by an electrode or cold emission electrons from a flaw of a low electrode material, a burr, or a foreign substance attached to the low electrode. It is known that charge-up easily occurs and causes creeping discharge. The creeping discharge causes deterioration of the electronic components inside the cathode ray tube, a change in focus, and a disturbance in an image such as a conver drift. Conventionally, a conductive coating is provided inside a cathode ray tube in order to prevent creeping discharge due to such accelerated charge-up of electrons and an insulator. For example, in JP-B-63-10859, a metal vapor-deposited film is formed on both an insulating support (bead glass) for supporting a plurality of electrodes and an inner wall of a neck portion using a metal wire or ribbon as an evaporation source. A method of forming is disclosed.
By providing a metal deposition film on each of the insulating support and the inner wall of the neck as described above, a partial potential increase of the inner wall of the neck and the insulating support is prevented, and the accelerated charge of electrons and the insulator is increased. It is intended to prevent creeping discharge caused by the above.

[0004]

However, in this conventional method, a metal vapor deposition source such as a wire or a ribbon is installed inside a neck portion to obtain a metal vapor deposition film, and the entire inside of the cathode ray tube is vacuumed. After that, a high-frequency coil is applied from an external high-frequency coil to form a metal vapor-deposited film.Therefore, unnecessary vapor sources such as wires and ribbons remain in the cathode ray tube, and Depending on the state, there is a problem that the evaporation source itself becomes a stray source. In addition, a defect such as thermal deformation may occur in the electron gun due to heating by high frequency. Furthermore, in this method, since the metal deposition film is formed not only on the inner wall of the neck portion but also on the insulating support, the metal film formed on the insulating support serves as a discharge path due to this. Discharge may occur. In addition, in the conventional method, the control of the amount of deposition, that is, the thickness of the metal deposition film, there are various manufacturing constraints such as the contact between the deposition source and the insulating support and the positional relationship between the high-frequency coil and the deposition source, There are problems such as many factors that need to be controlled in manufacturing.

The present invention has been made in view of such a problem, and an object of the present invention is to effectively suppress creeping discharge of an insulator caused by charge-up caused by accelerated electrons occurring around an electron gun. An object of the present invention is to provide a cathode ray tube capable of eliminating the causes of image disturbance such as deterioration of internal electronic components, change in focus, and conver drift.

The present invention also provides a method for manufacturing a cathode ray tube which can easily realize the above-described cathode ray tube without leaving a deposition source such as a wire or a ribbon for forming a conductive film inside the cathode ray tube. It also aims to provide.

[0007]

A cathode ray tube according to the present invention includes a panel portion having a phosphor screen formed thereon, and a funnel portion having a neck portion facing the phosphor screen and integrated with the panel portion. A plurality of electrodes arranged in the direction of emitting an electron beam on the front surface of the hot cathode structure, and an electron gun mounted inside the neck portion, between two electrodes among the plurality of electrodes of the electron gun. And a conductive film for preventing creeping discharge provided on the inner wall surface of the neck portion facing the gap or the electrode.

In the method of manufacturing a cathode ray tube according to the present invention, after assembling the panel portion and the funnel portion, the panel portion and the funnel portion are integrated, and the conductive material for preventing creeping discharge is formed on the inner wall surface of the neck portion through the open end. Forming a conductive coating, and mounting an electron gun in the neck from the open end after forming the conductive coating, and then sealing the open end of the neck.

More specifically, in the method of manufacturing a cathode ray tube according to the present invention, after assembling the panel portion and the funnel portion, the panel portion and the funnel portion are integrated with one end of the neck portion opened. A step of forming a conductive film for preventing creeping discharge on the inner wall surface of the neck portion after vacuum-sealing a partial region of the neck portion, and forming a conductive film on the inner wall surface of the neck portion, and then forming a neck through the open end of the neck portion. Mounting the electron gun inside the part, and then sealing the open end of the neck part.

[0010] Another method of manufacturing a cathode ray tube according to the present invention comprises:
After assembling the panel portion and the funnel portion, respectively, temporarily fixing the panel portion and the funnel portion with a bonding material and forming a film made of an organic compound on the inner wall surface of the neck portion through the open end; The step of integrating the panel part and the funnel part with the step of integrating the panel part and the funnel part together with forming the conductive film for creeping discharge prevention by simultaneously firing the bonding material between the part and the funnel part, respectively, and forming the conductive film Mounting the electron gun into the neck from the open end and then sealing the open end of the neck.

In the cathode ray tube according to the present invention, creeping discharge caused by charge-up due to accelerated electrons is suppressed by the conductive film provided on the inner wall surface of the neck portion.

In the method for manufacturing a cathode ray tube according to the present invention, a conductive film for preventing creeping discharge is formed before the electron gun is mounted and the neck portion is sealed.

In another method of manufacturing a cathode ray tube according to the present invention, in one firing step, a conductive film for preventing surface discharge is formed and, at the same time, a panel portion and a funnel portion are integrated. Thereafter, an electron gun is mounted in the neck from the open end, and the open end of the neck is sealed.

[0014]

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

FIG. 1 shows a first embodiment of the present invention.
1 is a cutaway view of a cathode ray tube according to an embodiment of the present invention. The cathode ray tube 10 includes a panel portion 11 and a funnel (funnel) portion 12 made of glass. The panel portion 11 and the funnel portion 12 are fused (frit sealed) to each other by a bonding material such as frit glass. The inside is maintained in a high vacuum state. On the inner surface side of the panel section 11, fluorescent screens 14 of three colors of red, blue and green are provided. A color selection device (shadow mask) 15 is mounted behind the phosphor screen 14. The base end side of the funnel portion 12 is an elongated neck portion 13.
Has an electron gun 16 for irradiating the phosphor screen 14 with three electron beams of red, blue and green. Electron gun 1
The three electron beams of red, blue and green emitted from 6 are each deflected by a deflection yoke 17 and then applied to a phosphor of a corresponding color on the phosphor screen 14 through a color selection device 15.

The electron gun 16 has a plurality of electrodes, for example, a first grid G1, a second grid G2, and a plurality of electrodes in front of a hot cathode structure (not shown) having three cathodes for red, green and blue.
Third grid G3, fourth grid G4, fifth grid G
5, a sixth grid G6 and a seventh grid G7 are arranged in this order. Each of these electrodes (G1 to G7) is an insulating support (bead glass) 18
Fixedly held. The first grid G1 is a control electrode,
The second grid G2 is an acceleration electrode. First grid G1
Is connected to, for example, the ground (0 V), and the second grid G2
Is applied with a voltage of 300V. Third grid G3
The fourth grid G4 and the fifth grid G5 are focusing electrodes, respectively. A voltage of, for example, 27 KV is applied to each of the third grid G3 and the fifth grid G5, and a variable voltage of, for example, about 8 to 9 KV is applied to the fourth grid G4. Each of the sixth grid G6 and the seventh grid G7 is a plate-like convergence electrode constituting a deflecting plate.
To 26 KV, and the seventh grid G7 has, for example, 2
A voltage of 7 KV is applied respectively. A plurality (for example, four) of claw-shaped spring pieces 19 are provided at the tip of the electron gun 16.
The electron gun 16 is elastically fixedly supported on the inner wall of the neck portion 13 by the spring pieces 19.

Here, a case where charge-up occurs due to electron beam irradiation from the electron gun 16 and electron leakage from the electrodes will be described with reference to FIG. This figure is
2 shows a portion including one cathode 21 and a portion including a first grid G1 and a second grid G2 in the vicinity of the cathode 21 in the hot cathode structure 20 constituting the electron gun 16. FIG.
The tip of the cathode 21 is impregnated with an electron emitting substance 22. The first grid G1 is disposed to face the cathode 21, and the second grid G2 is disposed at a predetermined interval from the first grid G1. The amount of the electron beam emitted from the hot cathode structure 20 is mainly the first grid G
It is controlled by the relative potential difference between 1 and the cathode. The first grid G1 and the second grid G2 are provided with electron beam transmission holes 23 and 24, respectively.
Is transmitted.

In the cathode ray tube 10, for example, the cathode 2
1 is applied with a voltage of 100 V, the first grid G1 is supplied with a voltage of 0 V, and the second grid G2 is supplied with a voltage of 300 V, whereby a heater (not shown) incorporated in the cathode 21 is heated. B is emitted. This electron beam B is deflected by an electric field created by applying a potential difference between the sixth grid G6 and the seventh grid G7 (FIG. 1) provided at the tip of the electron gun 16 and shown in FIG. The light is converged on the phosphor screen 14 of the panel unit 11. By the way, in such a cathode ray tube 10,
Not all the electron beams B pass through the electron beam transmission holes 23 and 24, and the first grid G1 and the second grid G
A so-called electron leak occurs from the gap between the electron gun 2 and a part of the electron gun 16 diverging to the outside of the electron gun 16 as the electron beam B ₁ . This electron beam B ₁ collides with the neck portion 13 (FIG. 1), which is an insulator around the electron gun 16, causing charge-up. Therefore, as described above, electrons travel on the inner wall of the neck portion 13, so-called creeping discharge. Occurs. Thus electron leakage is mainly likely to occur between the first grid G1 and second grid G2, the electron beams B ₁ strikes the neck 13 (FIG. 1).

For this reason, in the present embodiment, in the inner wall surface of the neck portion 13, a region mainly opposed to a region where electron leakage is concentrated (between the first grid G1 and the second grid G2). The conductive film 25 is formed. The conductive film 25 is formed on the neck portion 13.
May be formed over the entire circumference of the inner wall surface. However, for example, it is desirable to divide the inner wall surface into a plurality of regions along the inner wall surface according to the purpose for the following reason.
In addition, not only the region facing between the first grid G1 and the second grid G2 but also the region facing other electrodes may be formed to be wide along the width direction (electron beam irradiation direction). Good.

The conductive film 25 is made of, for example, titanium (Ti),
It is formed of a metal such as chromium (Cr) or nickel (Ni), or a conductive substance such as a conductive oxide film such as indium oxide (In ₂ O ₃ ). The thickness of the conductive film 25 is, for example, several nm to several hundred nm, and the width thereof is, for example, 4 mm.
It is about. The surface resistance of the conductive film 25 is several KΩ / □ ~
It is in the range of several tens of MΩ / □, preferably 100 KΩ to several thousand K.
Ω / □.

In the cathode ray tube 10 according to the present embodiment, the electron beam B1 generated by the electron leakage from the gap between the first grid G1 and the second grid G2 collides with the conductive film 25, thereby causing the neck portion 13 Such charge-up of the insulator can be prevented, so that the occurrence of creeping discharge can be effectively suppressed. In addition, the conductive coating 25 of the present embodiment is formed only on the inner wall surface of the neck portion 13 because it is formed before the mounting of the electron gun 16 by a method described later, and is formed on the insulating support 18 of the electron gun 16. It is not formed around. Therefore, there is no adverse effect caused by the conductive film formed on the insulating support as described above. For this reason, deterioration of internal electronic components, focus change,
It is possible to eliminate a cause of image disturbance such as a conver drift.

Hereinafter, a method of manufacturing the cathode ray tube 10 will be described.

FIG. 2 is a block diagram for explaining the outline of the manufacturing process of the cathode ray tube 10. As shown in FIG. First, the panel section is assembled by forming the phosphor screen 14 on the panel section 11 and incorporating the color selection device 15 (step S10).
(0) and after assembling the funnel 12 (step S110), the panel 11 and the funnel 12 are fused together with frit glass (step S12).
0). Subsequently, a conductive film 25 is formed on the inner wall of the neck portion 13 of the funnel portion 12 by a method described later (Step S130). After forming the conductive film 25, the electron gun 16 is mounted inside the neck portion 13 through the open end 31, and the neck portion 13 is sealed while the inside of the cathode ray tube 10 is maintained at a high vacuum (step S140). Neck part 13
After sealing, the inside of the cathode ray tube 10 is discharged (high-pressure discharge) to clean (arc) the inside (step S150). After that, the deflection yoke 1
The cathode ray tube 10 is completed through other ordinary steps such as attaching external parts such as 7 (step S160).

As described above, in the method for manufacturing a cathode ray tube according to the present embodiment, the step of fusing panel portion 11 and funnel portion 12 with frit glass (step S12).
0) and a step of sealing the electron gun 16 (step S14)
0), the conductive film 25 is formed only on the inner wall surface of the neck portion 13 without forming the conductive film 25 on parts such as the insulating support 18 (FIG. 1). can do. In addition, the conductive coating 2
There is no possibility that the device parts used for forming the filter 5 remain inside the cathode ray tube 10.

Hereinafter, a method of forming the conductive film 25 on the inner wall of the neck portion 13 will be described more specifically. In the present embodiment, for example, the vacuum device 3 shown in FIG.
The conductive film 25 by the sputtering apparatus 32 including
Is formed. The cross-sectional shape of the neck portion 13 is substantially circular, and the terminal end is not sealed at this stage but is an open end 31. The sputtering device 32 is set inside the neck portion 13 through the open end 31.

The sputtering device 32 includes an internal seal member 33, a target 34, a mask 35, and an external seal container 36. The inner seal member 33 is formed of, for example, an elastic material such as rubber, and is 10 ^−2.
In order to maintain a vacuum of about -10 ^-5 Torr, the inner periphery of the circular neck portion 16 is formed so as to be pressed against the inner periphery of the circular neck portion 16 with an appropriate pressure without any gap in consideration of confidentiality. The target 34 is made of a metal such as chromium or nickel that becomes the conductive film 25 and also serves as a cathode. The mask 35 is formed in a cylindrical shape from a metal such as stainless steel, and also serves as an anode. The mask 35 is fixed to the inner seal material 33 at the upper end. For example, a DC voltage is applied between the target 34 as a cathode and the mask 35 as an anode. In the mask 35, a region where the conductive film is to be formed on the inner wall of the neck portion 13, that is, a region facing the gap between the first grid G1 and the second grid G2 and a nearby region in the example of FIG. An opening 35a is formed correspondingly. The outer seal container 36 is connected to the neck portion 1 via an O-ring 36a formed in a ring shape.
3 is fixed to the outer peripheral portion. The O-ring 36a is formed of a material equivalent to that of the inner seal member 33, and the outer seal container 36 and the neck 13 are formed through the O-ring 36a.
Is hermetically sealed. That is, in the sputtering device 32, the internal sealing member 33 installed inside the neck portion 13 and the open end 3
1 is hermetically sealed with the external seal container 36 that covers the cover 1.

The inner seal member 33 and the outer seal container 36
The region 37 formed between them is evacuated by a vacuum device 38. The vacuum device 38 includes an exhaust pipe 39 having one end facing the region 37 from the bottom of the outer seal container 36 and the other end having a vacuum pump (P) 40 installed therein,
An atmosphere pipe 41 branched from the exhaust pipe 39 is provided. The exhaust pipe 39 is provided with an open / close valve 39a, and the atmospheric pipe 41 is provided with an open / close valve 41a. Although not shown, for example, argon (Ar) is supplied as a discharge gas to the region 37 after the evacuation.

In the present embodiment, first, the panel portion 11 and the funnel portion 12 are fused, and the inner wall of the neck portion 13 is cleaned using pure water. Thereafter, the inner seal member 33, the target 34, and the mask 35 are attached to the inside of the neck portion 13 from the open end 31, respectively. Then, the outer seal container 36 is attached to the open end 31 via the O-ring 36a. Next, the vacuum pump 40 is operated to operate the exhaust pipe 39.
Through this, the inside of the sputtering apparatus 32, that is, a region 37 formed between the inner seal member 33 and the outer seal container 36 is evacuated to a vacuum state. The degree of vacuum is, for example, about 10 ⁻² to 10 ⁻⁵ Torr. After a predetermined degree of vacuum is reached, when a DC voltage (for example, 300 V) is applied for several seconds using the target 34 as an anode and the mask 35 as a cathode, the metal scatters from the target 34 and the scattered metal passes through the opening 35a of the mask 35. It passes through and accumulates on the inner wall of the neck portion 13. Thereby, the conductive film 25 is formed.

It is desirable that the thickness distribution of the conductive film 25 in the width direction has a gentle gradient such that it becomes thinner toward the end as shown in FIG. Concentration can be prevented, and the withstand voltage of the conductive film 25 can be improved. Specifically, 1 / 10-1 / 3 of the thickness d ₁ of the thickest portion of the film thickness d ₂ of the thinnest portion can be confirmed visually conductive coating 25 (e.g., d
₁ = 100 nm, d ₂ = 20 nm) and it is desirable to have a gentle thickness gradient. In particular, the conductive film 2
When the high-voltage electrode and the low-voltage electrode face each other on both sides of 5, the end on the high-voltage electrode side where the electric field tends to concentrate needs to have such a shape. The conductive coating 2
The control of the thickness distribution of No. 5 can be performed by appropriately setting the sputtering conditions described later, the distance d between the mask 35 and the inner wall surface of the neck portion 13, and the like.

After the conductive film 25 has been formed, the open / close valves 39a and 41a of the vacuum device 38 are switched, and
Atmospheric air is introduced into a region 37 formed between the inner seal member 33 and the outer seal container 36 through. Next, after the internal seal member 33 is loosened, the target 34 and the mask 35 are pulled out from the neck portion 13 together with the internal seal member 33. After that, after attaching the electron gun 16 to the inner wall of the neck portion 13 as described above, the cathode ray tube 10 is completed through sealing of the neck portion 13, an arcing process and the like.

As described above, in the method of manufacturing a cathode ray tube according to the present embodiment, after assembling the panel portion 11 and the funnel portion 12, before sealing the electron gun 16, the conductive film 25 for preventing creeping discharge is formed. Each member of the sputtering device 32 is connected to the open end 31 of the neck portion 13.
It can be mounted more easily, and only the neck portion 13 needs to be maintained in a vacuum state. Therefore, the sputtering device 32 can be simplified, and the amount of vapor deposition can be easily controlled.
The degree of freedom of work also increases.

Furthermore, in the present embodiment, the neck portion 13 is sealed, and the voltage is selectively applied only to the region where the conductive film 25 is formed. There is no influence. Further, the metal does not adhere to other parts, and there is no possibility that the adhesion of the metal may cause deterioration of the withstand voltage or the like.

[Second Embodiment] Next, a second embodiment of the present invention will be described.
An embodiment will be described. This embodiment is the same as the first embodiment except for the difference in the mask used for the sputtering apparatus.
Therefore, the same components as those of the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

As described above, in the first embodiment, the conductive film 25 is formed before the neck portion 13 is sealed, and thereafter, the electron gun 16 is inserted from the open end 31 of the neck portion 13. . However, when the electron gun 16 is inserted from the open end 31, the conductive coating formed on the inner wall of the neck portion 13 may be damaged by the spring piece 19 for attaching the electron gun as shown in FIG. In such a case,
The electric field concentrates on the damaged portion of the damaged conductive film, causing a decrease in withstand voltage.

In order to solve such a problem, in the present embodiment, when a conductive film is formed by the sputtering device 32, for example, a mask 5 as shown in FIG.
0 is used. FIG. 5A illustrates a side surface shape of the mask 50, and FIG. 5B is a cross-sectional view taken along a line AA in FIG. 5A. The mask 50 is formed of a metal such as stainless steel, has a cylindrical shape with a closed head, and has a plurality (four in the present embodiment) of openings 51 a to 51 a corresponding to a region where a conductive film is to be formed. 51d are formed. A region between the adjacent openings 51a to 51d is a shielding portion 52. This shielding part 52 is provided on the neck part 13.
Of the inner wall of the spring, the passages of the spring pieces 19 when the electron gun 16 is attached, and no conductive coating is formed on these corresponding regions. In this embodiment, sputtering is performed by the sputtering apparatus shown in FIG. 2 using this mask 50 instead of the mask 35 shown in FIG. At this time, the size of the mask 50 is desirably set to such a degree that a gap of about 1.0 mm is formed between the mask 50 and the inner wall surface of the neck portion 13 so as not to come into direct contact with the neck portion 13.

FIG. 6 shows a state in which a plurality of conductive films 25a are formed on the inner wall of the neck portion 13 by a sputtering apparatus incorporating the mask 50 shown in FIG. The region between the adjacent conductive films 25a is used as a passage 53 of the spring piece 19a for fixing the electron gun 16.

As described above, in the present embodiment, the conductive film for preventing creeping discharge is divided into a plurality of conductive films 25a, so that the spring piece 19 passes over the conductive film. Therefore, there is no possibility that the conductive film is peeled off or damaged by the spring piece 19. Therefore, the electric field does not concentrate on a part of the conductive film, and a decrease in withstand voltage can be prevented. It should be noted that even if the shape or passage of a member passing through the inner wall of the neck portion 13 after forming a spring piece or other conductive coating is changed by a model change or the like, only the shape and position of the opening of the mask are changed. Is fine.

[Third Embodiment] FIG. 7 shows a fourth embodiment of the present invention.
FIG. Note that the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted. In this embodiment mode, a film made of an organic compound is formed as the conductive film. That is, in the present embodiment, the nozzle 9 sprays an organic compound containing, for example, tin (Sn) -indium (In) from the tank 90.
1, an organic film 93 is formed by spraying on the wall surface of the neck portion 13, and then the organic film 93 is baked at a predetermined temperature and oxidized to form a conductive film (ITO).
(Indium-Tin Oxide)). At this time, the neck 13
Is provided with a mask 92, and an organic film 93 is formed through an opening 92a provided in the mask 92. Note that such an organic film may be formed by application using a brush. However, in order to form a film having a smooth and stable shape as described above, it is preferable to form the organic film using a spray-type nozzle.

FIG. 8 shows an example of a preferred process in the present embodiment. First, a panel assembly process for forming the phosphor screen 14 on the panel unit 11 and incorporating the color selection device 15 (step S200), and a funnel assembly process for assembling the funnel unit 12 (step S200)
210), the panel section 11 and the funnel section 1
2 is coated with frit glass (step S
220). After applying the frit glass, a film made of the above-described organic compound of tin (Sn) -indium (In) is formed (step S230), and thereafter, for example, 450 °
At the temperature of C, the film made of frit glass and the organic compound between the panel portion 11 and the funnel portion 12 is simultaneously fired, thereby sealing between the panel portion 11 and the funnel portion 12 and oxidizing the organic compound. A conductive film (ITO film) is formed (Step S240). Thereafter, similarly to the first embodiment, the electron gun sealing step (step S250) and the arcing step (step S26)
0), and through other steps, the cathode ray tube 10 is completed (step S270).

Although the present invention has been described with reference to various embodiments, the present invention is not limited to the above-described embodiments and can be variously modified. For example, in the first to third embodiments, the DC-driven sputtering apparatus has been described. However, an AC-driven sputtering apparatus using a high frequency may be used. Further, not only the sputtering method but also other methods such as aluminum (A
The conductive film may be formed by an evaporation method using 1).

[0041]

As described above, according to the cathode ray tube according to the present invention, since the conductive film is formed on the inner wall surface of the neck portion, the insulator is charged up by the accelerated electrons, and the cold charge is increased. It is possible to effectively suppress creeping discharge caused by charge-up caused by emission, and to eliminate the cause of image disturbance such as deterioration of internal electronic components, focus change, and conver drift.

According to the method of manufacturing a cathode ray tube according to the present invention, a conductive film for preventing creeping discharge is formed before an electron gun is mounted and a neck portion is sealed. The conductive film can be formed only on the inner wall of the neck without leaving the equipment for forming the film inside the cathode ray tube and without hindering the internal components such as the electron gun. There is an effect that the cathode ray tube of the present invention can be formed stably.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration of a cathode ray tube according to a first embodiment of the present invention, with a main part thereof cut away.

FIG. 2 is a flowchart for explaining a manufacturing process of the cathode ray tube of FIG.

FIG. 3 is a cross-sectional view illustrating a configuration of a sputtering apparatus for forming a conductive film on a neck portion of the cathode ray tube of FIG.

FIG. 4 is a cross-sectional view illustrating a state of forming a conductive film by the sputtering apparatus of FIG.

FIGS. 5A and 5B show a configuration of a mask for a sputtering apparatus according to a second embodiment of the present invention, wherein FIG. 5A is a side view, and FIG. It is sectional drawing of the A line direction.

FIG. 6 is a diagram for explaining a state of forming a conductive film using the mask of FIG. 5;

FIG. 7 is a sectional view illustrating a configuration of a spraying device according to a third embodiment of the present invention.

FIG. 8 is a flowchart for explaining a manufacturing process of a cathode ray tube using the spraying device of FIG. 7;

FIG. 9 is a diagram for explaining a state of occurrence of creeping discharge in a cathode ray tube.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Cathode ray tube, 11 ... Panel part, 12 ... Funnel part, 13 ... Neck part, 14 ... Phosphor screen, 15 ... Color sorter, 16 ... Electron gun, 20 ... Hot cathode assembly, 21 ... Cathode, 22 ... Electron emission Substances, 23, 24: electron beam transmitting holes, 25, 25a, 90: conductive coating, 31: open end,
32 ... sputtering device, 33 ... inner seal member, 3
4 Target, 35, 50, 92 Mask, 35a
Opening, 36: external seal container, 38: vacuum device, 91
... spray nozzle, G1 ... first grid, G2 ... second grid, G3 ... third grid, G4 ... fourth grid, G
5: fifth grid, G6: sixth grid, G7: seventh grid

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Tsuneo Whip 6-7-35 Kita Shinagawa, Shinagawa-ku, Tokyo Inside Sony Corporation

Claims (12)

[Claims] 1. A cathode ray tube including a panel portion on which a phosphor screen is formed, and a funnel portion having a neck portion facing the phosphor screen and integrated with the panel portion, wherein an electron is provided on a front surface of the hot cathode structure. An electron gun configured by arranging a plurality of electrodes in a beam radiation direction and mounted inside the neck portion; and a gap between two electrodes of the plurality of electrodes of the electron gun or opposed to the electrodes. A cathode ray tube comprising: a conductive film for preventing creeping discharge provided on an inner wall surface of a neck portion. 2. The cathode ray tube according to claim 1, wherein said conductive coating is formed at a plurality of positions along an arrangement direction of a plurality of electrodes. 3. The cathode ray tube according to claim 1, wherein said conductive coating is formed by dividing into a plurality of portions along the circumferential direction of the inner wall surface of the neck portion. 4. The electron gun has a plurality of spring pieces for holding the inner wall surface of a neck portion at a tip end thereof, and the conductive coating is divided into a plurality of regions excluding a passage of the plurality of spring pieces. 4. The cathode ray tube according to claim 3, wherein the cathode ray tube is formed by forming the cathode ray tube. 5. The cathode ray tube according to claim 4, wherein a thickness gradient of at least an end on the high voltage electrode side of both ends in a width direction of the conductive film is formed gently. 6. A method of manufacturing a cathode ray tube including a panel portion on which a phosphor screen is formed, and a funnel portion having a neck portion facing the phosphor screen and integrated with the panel portion. Forming a conductive film for preventing creeping discharge on the inner wall surface of the neck portion through the open end after integrating the panel portion and the funnel portion, and forming an open end after forming the conductive film. Mounting the electron gun in the neck portion, and then sealing the open end of the neck portion. 7. A method according to claim 1, wherein the conductive film is divided into a plurality of portions along a circumferential direction of an inner wall surface of the neck portion. 7. The method for manufacturing a cathode ray tube according to claim 6, wherein the spring piece is slid along a passage between the plurality of divided conductive films. 8. A method for manufacturing a cathode ray tube including a panel portion on which a phosphor screen is formed, and a funnel portion having a neck portion facing the phosphor screen and integrated with the panel portion, wherein the panel portion and the funnel are provided. After assembling the respective parts, a step of integrating the panel part and the funnel part with one end of the neck part opened, and after partially sealing the neck part under vacuum, the inner wall surface of the neck part Forming a conductive film for preventing creeping discharge, mounting an electron gun in the neck through the open end of the neck after forming the conductive film, and then sealing the open end of the neck A method for manufacturing a cathode ray tube, comprising: 9. A step of forming a conductive film for preventing creeping discharge on the inner wall surface of the neck portion through the open end,
An inner seal member for hermetically sealing the inside of the neck portion and an outer seal container for sealing the open end of the neck portion are surrounded by the outer seal container, the inner seal member, and each of the wall surfaces of the neck portion. 9. The method for manufacturing a cathode ray tube according to claim 8, wherein the conductive film is formed in a vacuum atmosphere in the set area. 10. The method according to claim 1, wherein the conductive coating is formed on an outer seal container.
A metal target which is provided in a vacuum region surrounded by each of the inner seal member and the wall of the neck and also serves as an anode, and which is provided between the metal target and the inner wall of the neck and has a cathode The method for manufacturing a cathode ray tube according to claim 9, wherein the cathode ray tube is formed by a sputtering device including a mask that also serves as a mask. 11. A method for manufacturing a cathode ray tube including a panel portion having a phosphor screen formed thereon and a funnel portion having a neck portion facing the phosphor screen and integrated with the panel portion, wherein the panel portion and the funnel are provided. After the respective parts are assembled, the panel part and the funnel part are temporarily fixed with a bonding material, and a film made of an organic compound is formed on the inner wall surface of the neck part through the open end. Forming a conductive film for preventing creeping discharge and simultaneously integrating the panel portion and the funnel portion by simultaneously firing the bonding material between the panel portion and the open end after forming the conductive film. Mounting the electron gun in the neck portion, and then sealing the open end of the neck portion. 12. The step of forming a film made of an organic compound on the inner wall surface of the neck portion, wherein the film made of the organic compound is formed by spraying the organic compound through a mask provided inside the neck portion. 11
The method for manufacturing the cathode ray tube according to the above.