JP2003249183A - Image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a discharge at a creepage surface of a member surface, and to reduce damage due to the discharge even when the discharge occurs. <P>SOLUTION: On a face plate 1017, an image display region 101 as a phosphor region is formed, and a conductive member 102 is formed to surround the image display region 101, an anode electrode outer border 104, and a high voltage input terminal contact section 100. The conductive member 102 has a sheet resistance of 10<SP>3</SP>Ω/square or more, and a thickness to set to 5 μm or more. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a display device using an electron beam.

[0002]

2. Description of the Related Art Conventionally, as an image forming apparatus using electron-emitting devices, an electron source substrate having a large number of cold cathode devices formed thereon,
A flat-type electron beam display panel is known in which an anode electrode and an anode substrate provided with a phosphor are opposed to each other in parallel and the inside is evacuated to a vacuum. An example of such an image forming apparatus using a surface conduction electron-emitting device is disclosed in, for example, US Pat. No. 5,066,883. A flat panel electron beam display panel using a surface conduction electron-emitting device can be made lighter and have a larger screen than a CRT currently widely used, and a flat panel display panel using a liquid crystal or It is possible to provide an image with higher brightness and higher quality than other flat display panels such as plasma displays and electroluminescent displays.

FIG. 9 is a schematic view of a display panel, which is an example of an image forming apparatus using an electron-emitting device, as seen from the horizontal direction of the image display surface.

The flat electron beam display panel of this image display device constitutes a vacuum container by a rear plate 2015, a support frame 203, and a face plate 2017 which is arranged so as to face the rear plate 2015. An electron source region 202 provided with an electron-emitting device is formed on a rear plate 2015 which also serves as an electron-source substrate, and one phosphor corresponds to one electron-emitting device.
Row-direction wirings and column-direction wirings are electrically connected to the electron-emitting devices. The support frame 203 holds the rear plate 2015 and the face plate 2017 at predetermined intervals, and also functions as a support member for atmospheric pressure. The inside of the vacuum container including the rear plate 2015, the support frame 203, and the rear plate 2015 is 10 ⁻⁴ [P
Since it must be maintained at a pressure of about a] in FIG.
As shown in FIG. 3, a Ba evaporation type getter member 200 is arranged outside the image region together with the support 201, and after the vacuum container is completely closed, Ba is scattered by high-frequency heating or the like to form a getter film, thereby forming a getter film. Is configured to hold.

On the other hand, in order to accelerate the electrons emitted from the electron source, a high voltage of several hundred V to several [kV] or more is applied between the electron source region 202 and the image forming member 204. The brightness of the image forming apparatus largely depends on the anode voltage (Va) applied to the anode electrode, and it is necessary to apply a high value of the anode voltage to increase the brightness.

[0006]

However, when the anode voltage is increased, the leakage electric field to the periphery of the getter member or the support outside the image area also rises, and the edge portion of the getter member or the support is increased. Alternatively, there may be a problem of discharge in a portion where the electric field is likely to be concentrated, such as an interface between the support and the rear plate.

Further, of the outside of the four sides of the image area,
Even if the structure such as the support of the getter member or the spacer support does not exist outside the image area as described above, if the distance between the support frame and the image area is reduced for the purpose of downsizing. In some cases, creeping discharge on the inner surface of the support frame becomes a problem.

The above-mentioned discharge suddenly occurs during image display, not only disturbing the image, but also significantly deteriorating the electron source near the discharge location, and thereafter there is a possibility that normal display cannot be performed.

In order to solve the above problem, a predetermined conductive member is provided in the vacuum container, and the potential of the conductive member is regulated to a predetermined value equal to or lower than the anode voltage Va, thereby confining the above-mentioned leakage electric field. We are studying a configuration that reduces the concentration of electric field on a structure such as a getter member. For example, the conductive member is provided so as to surround the anode electrode. This makes it possible to confine the electric field between the conductive member and the anode electrode, and avoid electric field concentration near the structure outside the image region.

However, in the above configuration, if a discharge should occur when Va is raised for the purpose of further increasing the brightness, the charge accumulated in the anode electrode instantly becomes a discharge current at the discharge location. I will concentrate. If a discharge with a large current flowing in the space, such as arc discharge, occurs between the anode electrode and the conductive member, a high resistance film is formed on the inner wall surface of the vacuum container between the anode electrode and the conductive member. Even if it is done, the large current will damage the conductive member, the metal back, the phosphor, and the like. When the degree of damage to the conductive member is large, the subsequent function of confining the electric field does not work effectively, which may further induce discharge.

Therefore, the present invention has been made in view of the above-mentioned problems, and suppresses the occurrence of discharge on the surface of the surface of a member such as a face plate and a rear plate, and at the same time, an image forming apparatus using an electron source. An object of the present invention is to provide an image forming apparatus having high reliability by preventing damage to the image forming apparatus by significantly reducing damage caused by the electric discharge even when electric discharge occurs inside.

[0012]

In order to achieve the above object, an image display device of the present invention comprises a rear plate on which an electron source is arranged and an anode electrode for accelerating an electron beam from the electron source. In an image forming apparatus having a vacuum container formed by facing a face plate having a phosphor region that emits light by being irradiated with a line through a support frame, an image forming apparatus is provided on the inner surface of the face plate outside the phosphor region. At least one conductive member is provided in the portion, the sheet resistance value of the conductive member is 10 ³ [Ω / □] or more, and the thickness t of the conductive member is 5 [μm] or more. Characterize.

In the image forming apparatus of the present invention having the above structure, the sheet resistance value of the conductive member itself is 10 ³ [Ω / □].
Since it is as high as the above and its thickness t is as large as 5 [μm] or more, the discharge current is limited even if an arc discharge occurs between the conductive member and the anode electrode, and the conductive member and the anode electrode are also restricted. And the degree of damage to the phosphor is reduced. Therefore, the function of confining the electric field by the conductive member after the discharge has occurred can be continuously exerted.

Further, the image display device of the present invention may have a conductive film electrically connected to the anode electrode and the conductive member, between the anode electrode and the conductive member.

Further, in the image display device of the present invention, the sheet resistance value of the conductive member may be 10 ⁶ [Ω / □] or less. In this case, the potential regulating electrode has a sufficient function of confining the electric field. It is possible to exert to the.

Further, in the image display device of the present invention, the conductive member and the conductive film may be arranged all around the phosphor region. In this case, the conductive member and the conductive film are arranged around the entire circumference so as to surround the phosphor region, and when it becomes necessary to narrow the outside of the image region for the purpose of saving space and improving the landscape, Even when the support frame approaches the image area, local concentration of the electric field can be prevented and damage due to discharge can be prevented.

Further, in the image display device of the present invention, at least one point in the conductive member may be regulated to the ground potential. In this case, even when a discharge occurs,
The discharge current escapes to the ground, which is effective in terms of safety and health.

If the sheet resistance value of the conductive member is lower than the sheet resistance value of the conductive film, the function of confining the electric field can be sufficiently exerted, and especially the sheet resistance of the conductive film is 10 ⁷ [. Ω / □] to 10 ¹⁴ [Ω / □] can withstand a high voltage applied between the conductive member and the anode electrode, and prevent charging due to incident electrons or ions, resulting in charge-up. It is possible to prevent the discharge.

If the electron source is composed of a plurality of electron-emitting devices electrically connected to the wiring, various display patterns corresponding to the electron-emitting devices can be stably displayed with high brightness and high contrast. Is possible. In particular, when a plurality of electron-emitting devices use an electron source electrically connected in a matrix by a plurality of row-direction wirings and a plurality of column-direction wirings, by appropriately selecting and driving these wirings, a desired electron source can be obtained. It becomes possible to stably display an image with high brightness and high contrast at any time.

Further, if a cold cathode element is used as the electron-emitting device, it is possible to provide a thin image forming apparatus capable of stably displaying an image of high brightness and high contrast. By using the emitting element, it is possible to provide a thin image forming apparatus capable of stably displaying a high-brightness / high-contrast image, which is relatively simple in manufacturing process and can be enlarged.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the present invention will be described below. However, the dimensions, materials, shapes, relative positions, and the like of the components described in this embodiment are not intended to limit the scope of the present invention to them unless otherwise specified. .

First, the structure of the face plate of this embodiment will be described.

FIG. 1 is a schematic plan view of the face plate as seen from the inner surface of the vacuum container, and FIG. 2 is a schematic cross-sectional view taken along the line AA 'in FIG.

As the face plate 1017, soda lime glass or soda lime glass having a SiO ₂ coating formed on its surface,
Various materials are used according to the conditions, such as glass with reduced Na content and quartz glass.

On the inner surface of the face plate 1017,
An image display area 101, which is a phosphor area, is formed, and is a part of the anode electrode, and the outer periphery 104 of the anode electrode corresponding to the outer periphery of the metal back, the outer periphery of the black matrix, or the like is the image display area 101. Also, it is arranged so as to surround the high-voltage introduction terminal contact portion 100 electrically connected to the high-voltage introduction terminal (not shown). Further, the conductive member 102 includes the image display area 101, the outer periphery 104 of the anode electrode, and the high-voltage introduction terminal contact portion 100.
It is formed so as to surround the circumference of. Further, a conductor contact portion 103 having a wide width suitable for abutting the electrode terminal is formed in the upper right corner of the conductive member 102 in the drawing. Further, the image display area 101 and the conductive member 10
A conductive film 105 is formed in the region between the two.

As will be described later, as electron-emitting devices arranged on the substrate 1011 of the rear plate 1015,
For example, when a cold cathode device is used, the drive voltage of the device with respect to a reference potential (eg, ground potential) is approximately ± several tens of V or less. On the other hand, the voltage applied to the anode electrode is several hundred V to several tens of kiloV with respect to the reference potential. Therefore, when the potential of the conductive member 102 is used as a reference potential, an electric field applied between the conductive member 102 and an electron source having a plurality of electron-emitting devices causes an image forming the conductive member 102 and the anode electrode. It can be ignored because it is much smaller than the electric field applied between the display region 101 and the outer periphery 104 of the anode electrode. Therefore, the image display area 10
The withstand voltage outside 1 is the same as the image display region 101 and the conductive member 1.
It suffices to consider only the creeping breakdown voltage between the two.

Therefore, the structure can be freely arranged in the region outside the conductive member 102 without paying attention to the discharge withstand voltage. That is, the distance between the conductive member 102 and the support frame 1016 (see FIG. 5) can be shortened, which is effective in reducing the size and weight, and the degree of freedom in designing the configuration near the support frame 1016 can be improved. In particular,
It is no longer necessary to pay attention to a material such as a protrusion of frit glass, which will be described later, which is an adhesive agent between the supporting frame 1016 and the rear plate 1015, and which may have been conventionally discharged.

Further, the conductive film 105 plays a role of preventing electrification, and when a reflected electron or the like from the face plate 1017 reaches a region between the image display region 101 and the conductive member 102, a minute current is made to flow. Neutralize them by. Note that the sheet resistance value of the conductive film 105 is preferably 10 ⁷ [Ω / □] to 10 ¹⁴ [Ω / □]. The material and configuration of the conductive film 105 are not particularly limited as long as they exhibit an antistatic function. As an example,
Examples thereof include metal thin films, oxides, nitrides, semiconductors, carbon-containing substances, and combinations thereof.

Further, as a feature of the present invention, the conductive member 1
The sheet resistance value of 02 is 10 ³ [Ω / □] or more, and more preferably 10 ⁶ [Ω / □] or less. The thickness t of the conductive member 102 is set to 5 [μm] or more. Since the sheet resistance value of the conductive member 102 is high as described above, even if arc discharge occurs between the conductive member 102 and the anode electrode, the discharge current is limited and degassing from the member is suppressed. , Arc discharge disappears quickly. Further, since the thickness of the conductive member 102 is sufficiently large, it is possible to prevent the electrodes from being completely destroyed when electric discharge occurs. Therefore, the degree of damage to the conductive member 102, the anode electrode, and the phosphor is reduced. As described above, since the great damage due to the discharge can be reduced, the function of confining the electric field by the conductive member 102 after the discharge can be continuously exerted.

The conductive member 102 may have any material and structure as long as it has the above resistance value and thickness. For example, a transparent electrode such as ITO or P
Examples thereof include those containing bO as a main component and mixed with fine metal particles, fillers of carbon particles, or a glass binder and baked, thin films of metal, oxides, nitrides, semiconductors, and the like.

Next, an example of a method of manufacturing the face plate will be described.

As the face plate substrate, SiO ₂
Layered soda lime glass is used. First, the high-voltage introduction terminal contact portion 100 and the conductive member 102 that surrounds the image display region 101 are formed by printing a glass binder containing carbon in a glass paste and firing it. The width of the conductive member 102 is W1 =
2 [mm], which is 10 from the end of the image display area 101.
It is formed so as to surround the image display area 101 at a distance of [mm]. The amount of carbon contained in the glass paste is adjusted so that the sheet resistance of the conductive member after firing is 10 ³ [Ω / □] to 10 ⁶ [Ω / □]. Further, the thickness t of the conductive member 102 is set to 5 [μm].

Next, using a glass paste and a black pigment paste containing a black pigment, a black matrix 1010 was prepared by screen printing in a matrix as shown in FIG. In the present embodiment, the black matrix is manufactured by the screen printing method, but it is not limited to this, and may be manufactured by, for example, the photolithography method. Further, as the material of the black matrix 1010, a black pigment paste containing a glass paste and a black pigment is used, but the material is not limited to this, and carbon black or the like may be used, for example. The black matrix 1010 is
In this embodiment, as shown in FIG. 3, the matrix is formed, but the present invention is not limited to this, of course, and a stripe arrangement (for example, FIG. 4A) or a delta arrangement (for example, FIG. 4B). And other arrangements may be used.

Next, as shown in FIG. 3, a red (R), green (G), and blue (B) phosphor paste was used to form a matrix in the openings of the black matrix 1010 by screen printing. did. Of course, the present invention is not limited to this, and it may be produced by, for example, a photolithography method. Further, the method of separately coating the phosphors is not limited to the striped array, and may be a delta array as shown in FIG. 4B or an array other than that, depending on the black matrix. .

Next, a resin intermediate film is formed by a filming process well known in the field of cathode ray tubes, and then a metal vapor deposition film (Al in this embodiment) is formed, and finally the resin intermediate film is removed by thermal decomposition. Metal back 1 by making
019 was produced.

A transparent electrode made of, for example, ITO, ATO, tin oxide or the like is provided between the face plate substrate 1017 and the fluorescent film 1018 for the purpose of applying an acceleration voltage and improving the conductivity of the fluorescent film. Good.

The formation of the conductive film 105 does not limit the manufacturing procedure and may be performed during any of the above steps. However, when masking is required at the time of film formation such as sputtering, in order to avoid damaging or contaminating the phosphor or metal back 1019 which is the structure of the image display area 101 by the mask, the phosphor or metal back is avoided. It is preferable to carry out before forming since the probability of disturbing the image display area 101 is reduced.

Next, the structure and manufacturing method of the display panel of the image forming apparatus to which the present invention is applied will be described with reference to specific examples.

FIG. 5 is a perspective view of the display panel used in this embodiment, in which a part of the panel is cut away to show the internal structure.

In the figure, a rear plate 1015 and a support frame 10
16 and a face plate 1017 arranged to face the rear plate 1015 form an airtight container for maintaining a vacuum inside the display panel. When assembling the airtight container, it is necessary to seal the joints of the respective members in order to maintain sufficient strength and airtightness. 10 at ~ 500 [℃]
Sealing was achieved by firing for more than a minute. A method of evacuating the inside of the airtight container will be described later. Further, since the inside of the airtight container is maintained at a pressure of about 10 ⁻⁴ [Pa], the spacer 1020 is used as an atmospheric pressure resistant structure in order to prevent the airtight container from being broken by atmospheric pressure or an unexpected impact. Is provided.

Next, an electron source that can be used in the image forming apparatus of this embodiment will be described.

The electron source used in this image forming apparatus is formed by arranging a plurality of cold cathode elements 1012 on the substrate 1011.

The cold cathode elements 1012 are arranged in a ladder arrangement in which the cold cathode elements 1012 are arranged in parallel and both ends of each element are electrically connected by wiring (hereinafter, ladder arrangement electron source substrate and And a simple matrix arrangement (hereinafter referred to as a matrix-type arrangement electron source substrate) in which the X-direction wiring and the Y-direction wiring of the pair of device electrodes of the cold cathode device 1012 are electrically connected. An image forming apparatus having a ladder type electron source substrate requires a control electrode (grid electrode) which is an electrode for controlling the flight of electrons from the electron-emitting device.

The rear plate 1015 has a substrate 1011.
Is fixed, and N × M cold cathode elements 1012 are formed on the substrate 1011 (N and M are positive integers of 2 or more, and are appropriately set according to the target number of display pixels. For example, in a display device intended for high definition television display, N = 3000 and M = 100.
It is desirable to set a number of 0 or more. ). The N × M cold cathode devices are arranged in a simple matrix by M row-direction wirings 1013 and N column-direction wirings 1014.
A portion constituted by the substrate 1011, the cold cathode device 1012, the row-direction wiring 1013, and the column-direction wiring 1014 is called a multi-electron beam source. The multi-electron beam source used in the image display device of the present embodiment is not limited in the material, shape, or manufacturing method of the cold cathode element 1012 as long as it is an electron source in which the cold cathode element 1012 is arranged in a simple matrix wiring or in a ladder shape. . Therefore, for example, a cold cathode device 101 such as a surface conduction type emission device, a field emission type (FE type), or a metal / insulating layer / metal type (MIM type).
2 can be used.

Next, a structure of a multi-electron beam source in which surface conduction electron-emitting devices are arranged as cold cathode devices 1012 on a substrate and simple matrix wiring is described.

FIG. 6 shows a plan view of the multi-electron beam source used for the display panel of FIG. 5, and FIG. 7 shows a cross section taken along line BB ′ of FIG.

Cold cathode devices 1012, which are surface conduction electron-emitting devices, are arranged on the substrate 1011 and these devices are wired in a simple matrix by row-direction wirings 1013 and column-direction wirings 1014. An insulating layer (not shown) is formed between the electrodes at the intersection of the row wiring 1013 and the column wiring 1014 to maintain electrical insulation.

The surface conduction electron-emitting device is such that an electrode 1102 which is a pair of electrodes, a conductive thin film 1104 made of fine particles electrically connected to the electrodes 1102, and a conductive thin film are formed on an insulating substrate 1011. 1104 and an electron emitting portion 1105 which emits electrons. In this surface conduction electron-emitting device, the pair of electrodes 1
The interval of 102 is set to several hundred nm to several hundred μm, and the device electrode length is set to several μm to several hundred μm in consideration of the resistance value of the device electrode and electron emission characteristics. Further, the film thickness of the device electrode is set in the range of several tens nm to several μm in order to maintain the electrical connection with the conductive film 1104. Electrode 1102
Are formed by, for example, a photolithography technique.

The multi-electron source having such a structure is
After the row-direction wiring 1013, the column-direction wiring 1014, the inter-electrode insulating layer (not shown), and the device electrodes and the conductive thin film of the cold cathode device 1012 which is a surface conduction electron-emitting device are formed on the substrate 1011 in advance, the row direction It was manufactured by supplying power to each cold cathode element 1012 through the wiring 1013 and the column-direction wiring 1014 to perform the energization forming process and the energization activation process.

In the present embodiment, the multi-electron beam source substrate 1011 is fixed to the rear plate 1015 of the airtight container, but the multi-electron beam source substrate 10 is fixed.
When 11 has a sufficient strength, the substrate 10 of the multi-electron beam source is used as the rear plate of the airtight container.
11 itself may be used.

FIG. 8 is a schematic sectional view taken along the line AA 'in FIG. 5, and the reference numerals of the respective parts correspond to those in FIG. Spacer 10
Reference numeral 20 denotes a conductive film 11 formed on the surface of the insulating member 1 for the purpose of preventing electrification, and the inside of the face plate 1017 (metal back 1019 or the like) and the surface of the substrate 1011 (row direction wiring 1013 or column direction wiring). (Not shown)), the contact surface 3 of the spacer 1020 facing the (1) and the side surface 5 in contact with the low resistance film 21 are formed. Further, they are arranged with a necessary interval, and fixed to the inside of the face plate 101 and the surface of the substrate 1011 by the bonding material 1041. Further, the conductive film 11 is formed on at least the surface of the insulating member 1 that is exposed to the vacuum in the airtight container, and the low resistance film 21 on the spacer 1020 and the bonding material 1041 are interposed therebetween. Face plate 101
7 inside (metal back 1019 etc.) and the substrate 101
1 surface (row direction wiring 1013 or column direction wiring 101
4 (not shown in FIG. 8)). In this embodiment, the spacer 1020 has a thin plate shape, is arranged in parallel with the row-directional wiring 1013, and is electrically connected to the row-directional wiring 1013. Column direction wiring 101
4 (not shown in FIG. 8) and the row-direction wiring 1013 are insulated by the interlayer insulating layer 40.

As the spacer 1020, the substrate 1011 is used.
It has an insulation property of withstanding a high voltage applied between the upper row direction wiring 1013 and the column direction wiring 1014 and the metal back 1019 on the inner surface of the face plate 1017,
In addition, the spacer 1020 needs to have electrical conductivity to the extent that the surface of the spacer 1020 is prevented from being charged.

The bonding material 1041 needs to have conductivity so that the spacer 1020 is electrically connected to the row wiring 1013 and the metal back 1019. That is, a frit glass to which a conductive adhesive, metal particles or a conductive filler is added is suitable.

To evacuate the inside of the airtight container, after assembling the airtight container, an exhaust pipe (not shown) and a vacuum pump are connected to evacuate the airtight container to a pressure of about 10 ^-5 [Pa]. . Then, the exhaust pipe is sealed, but in order to maintain the pressure in the airtight container, a getter film (not shown) is formed at a predetermined position in the airtight container immediately before or after the sealing. The getter film is, for example, a film formed by heating a getter material containing Ba as a main component with a heater or high-frequency heating and vapor-depositing it, and the inside of the airtight container has a pressure of 10 ^{−3 to} 10 ⁻⁵ [Pa ⁵ ] Pressure is maintained.

In the image display device using the display panel described above, when a voltage is applied to each cold cathode element 1012 through the terminals D × 1 to D × m and Dy1 to Dyn outside the container, electrons are emitted from each cold cathode element 1012. Is released. At the same time, a high voltage of several hundred [V] to several [kV] is applied to the metal back 1019 through the terminal Hv outside the container to accelerate the emitted electrons, and the face plate 1017
Collide with the inner surface of. As a result, the phosphors of each color forming the phosphor film 1018 are excited and emit light, and an image is displayed.

The voltage applied to the cold cathode device 1012 is 12 to
About 16 [V], metal back 1019 and cold cathode device 1
The distance from 012 is about 0.1 [mm] to 8 [mm],
The voltage difference between the metal back 1019 and the cold cathode device 1012 is preferably about 0.1 [kV] to 20 [kV].

According to the image display device of this embodiment having the above-described structure, the conductive member 102 and the conductive film 105 are formed.
However, the support frame is arranged around the entire circumference so as to surround the image display area 101 which is a phosphor area, and when it becomes necessary to narrow the outside of the image area for the purpose of saving space and improving the scenery, the support frame is Even when approaching the image area, local concentration of the electric field can be prevented, and damage due to discharge can be prevented in advance.

Further, the sheet resistance value of the conductive member 102 itself is as high as 10 ³ [Ω / □] or more and the thickness t thereof is 5 or less.
Since it is as large as [μm] or more, even if arc discharge occurs between the conductive member 102 and the anode electrode, the discharge current is limited, and the degree of damage to the conductive member 102, the anode electrode and the phosphor is reduced. To be done. Therefore, the function of confining the electric field by the conductive member 102 after the electric discharge is generated can be continuously exerted. Therefore,
It is possible to prevent the image display device from being destroyed by electric discharge, and it is possible to improve reliability.

[0059]

EXAMPLES A more specific example of the above-described embodiment will be described below, but the present invention is not limited to the following examples. Further, in the following description, the reference numerals used in the description of the present embodiment will be used. (First
Example) First, the face plate shown in FIG. 1 was prepared.

The conductive member 102 was formed by forming and patterning an ITO film on the face plate substrate. In this embodiment, the sheet resistance value of the ITO film is 1 × 1.
It is set to be 0 ³ [Ω / □]. The arrangement and shape of the conductive member 102 are the same as the outer periphery 104 of the anode electrode.
The width W1 is set to 3 at the position where the distance W2 from is 5 [mm].
The thickness was set to [mm] and the thickness t (the amount of protrusion from the surface of the face plate 1017) was set to 5 [μm] so as to surround the image display region 101 and the high voltage introduction terminal contact portion 100.

The conductive film 105 was formed by depositing WGeN. The sheet resistance value of the conductive film 105 is 1 × 10 ⁷ [Ω /
□], and was formed between the conductive member 102 and the outer periphery 104 of the anode electrode so as to be electrically connected to both.

An image forming apparatus was prepared using the face plate 1017. At this time, the conductor contact portion 103
Through, the conductive member 102 was connected to the reference potential of the image forming apparatus. The reference potential was the ground potential.

As a result, the electric field is confined in the region outside the conductive member 102, and becomes substantially the reference potential unless a potential is applied.

Next, in the image display area, the anode voltage Va =
When 10 [kV] was applied, the periphery of the anode electrode 10
No electrical discharge occurred between No. 4 and the conductive member 102, and an image could be displayed as a problem in the image forming apparatus.

Further, the brightness is calculated and Va = 12 [k
V], discharge occurred between the outer periphery 104 of the anode electrode and the conductive member 102. However, damage to the outer periphery 104 of the anode electrode and the conductive member 102 was so small as not to affect the function of confining the electric field. Further, the image display region near the discharge location and the conductive film 105 were not damaged by the discharge. After that, Va = 12
It was driven at [kV] for 1 hour, and discharge was observed 5 times.
No damage that could affect the displayed image was observed, confirming the sustainability of the effect. Second Example In this example, a glass binder containing carbon was used to form the conductive member 102, and the thickness t was set to 10 [μm]. The other shapes and arrangements are the same as those in the first embodiment, and they were formed by screen-printing the above-mentioned binder and firing. At this time, the black matrix was simultaneously formed using the same binder. The carbon content in the glass binder was adjusted so that the sheet resistance of the conductive member 102 after firing was 1 × 10 ⁶ [Ω / □].

WGeN is used for the conductive film 105,
By adjusting the film formation conditions, the sheet resistance value is set to 1 × 10
^It was set to about ¹⁴ [Ω / □].

Using the face plate 1017,
The image forming apparatus was completed similarly to the first embodiment. When the electron source was driven with the anode voltage set to 10 [kV], no discharge was generated and a stable image could be displayed.

Further, the brightness is calculated and Va = 12 [k
V], a discharge occurred between the outer periphery 104 of the anode electrode and the conductive member 102, but almost no damage due to the discharge could be confirmed.

[0069]

As described above, according to the present invention, even if arc discharge occurs between the conductive member and the anode electrode, the discharge current can be limited and the conductive member is damaged. Since a conductive member having a thickness capable of suppressing the above is provided, damage due to discharge can be significantly reduced. As a result, it is possible to prevent the image forming apparatus from being damaged by the electric discharge and realize a highly reliable image forming apparatus.

[Brief description of drawings]

FIG. 1 is a schematic view of a face plate of an image forming apparatus according to an embodiment of the present invention as viewed from the inside of a vacuum container.

FIG. 2 is a schematic cross-sectional view taken along line AA ′ of the face plate of the image forming apparatus shown in FIG.

FIG. 3 is a schematic plan view showing a configuration of a black matrix.

FIG. 4 is a schematic plan view showing another configuration of the black matrix.

FIG. 5 is a schematic perspective view of a display panel of the image forming apparatus according to the embodiment of the present invention.

6 is a schematic plan view showing a multi-electron beam source used in the display panel of FIG.

7 is a schematic cross-sectional view of the display panel of FIG. 5, taken along line BB '.

8 is a schematic cross-sectional view showing a multi-electron beam source used in the display panel of FIG.

FIG. 9 is a schematic view of an example of a display panel in a conventional image forming apparatus viewed from the horizontal direction of an image display surface.

[Explanation of symbols]

1 Insulating member 3 contact surface 5 Sides 11, 105 Conductive film 21 Low resistance film 40 Interlayer insulation layer 100 High voltage introduction terminal contact part 101 image display area 102 conductive member 103 Conductor contact part 104 Around the outside of the anode electrode 1010 Black Matrix 1011 substrate 1012 Cold cathode device 1013 row direction wiring 1014 Column direction wiring 1015 Rear plate 1016 Support frame 1017 face plate 1018 fluorescent film 1019 Metal back 1020 spacer 1041 Bonding material 1102 electrode 1104 Conductive thin film 1105 Electron emission unit

Claims (11)

[Claims] 1. A rear plate on which an electron source is arranged, an anode electrode for accelerating an electron beam from the electron source, and a face plate having a phosphor region which emits light when irradiated with the electron beam are supported. In an image forming apparatus having a vacuum container formed to face each other with a frame interposed therebetween, at least one conductive member is provided on a portion outside the phosphor region on an inner surface of the face plate, and a sheet resistance value of the conductive member. Is 10 ³ [Ω / □] or more, and the thickness t of the conductive member is 5 [μm] or more. 2. The image forming apparatus according to claim 1, further comprising a conductive film electrically connected to the anode electrode and the conductive member between the anode electrode and the conductive member. 3. The sheet resistance value of the conductive member is 10
The image forming apparatus according to claim 1, wherein the image forming apparatus has a resistance of ⁶ [Ω / □] or less. 4. The image forming apparatus according to claim 2, wherein the conductive member and the conductive film are arranged over the entire circumference of the phosphor region. 5. At least one point in the conductive member is:
The image forming apparatus according to claim 1, wherein the image forming apparatus is regulated to a ground potential. 6. The image forming apparatus according to claim 2, wherein a sheet resistance value of the conductive member is lower than a sheet resistance value of the conductive film. 7. The sheet resistance value of the conductive film is 10
The image forming apparatus according to claim 6, wherein the image forming apparatus has a resistance of ⁷ [Ω / □] to 10 ¹⁴ [Ω / □]. 8. The image forming apparatus according to claim 1, wherein the electron source has a plurality of electron-emitting devices electrically connected to wiring. 9. The electron source has a plurality of electron-emitting devices, and each electron-emitting device is electrically connected in a matrix by a plurality of row-direction wirings and a plurality of column-direction wirings. The image forming apparatus according to claim 8. 10. The image forming apparatus according to claim 1, wherein the electron-emitting device is a cold cathode device. 11. The image forming apparatus according to claim 10, wherein the cold cathode device is a surface conduction electron-emitting device.