JP2001216923A - Image building apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image building apparatus in which discharge hardly occurs in a vacuum envelope using an electron-source substrate, and high- brightness display of images is possible. SOLUTION: In this image building apparatus which forms a rectangular envelope to maintain vacuum, with a rear plate, a face plate, a support frame and a spacer, the spacer is a long and narrow plain plate which spreads over the image building area and the end of which extends to the outside of the image building area, and with respect to its rising plane in relation to each plane of the rear plate and the face plate, its rising width is substantially equal to the distance d between the face plate and the rear plate in the image building area, and is smaller than the distance d outside the image building area. The extending end of the spacer is fixed with a fixation member existing outside the image building area.

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, and more particularly to an image forming apparatus having a spacer inside an envelope.

[0002]

2. Description of the Related Art Conventionally, as an image forming apparatus using an electron-emitting device, an electron source substrate (provided on a rear plate) using a large number of cold cathode devices and an anode substrate (face) provided with an anode electrode and a phosphor are used. Provided in a plate) are opposed to each other in parallel via a gap, and in a state where the gap is surrounded by a support frame, an envelope is formed, and the inside thereof is evacuated to a vacuum. Electron beam display panels are known.

In such an image forming apparatus, an apparatus using a surface conduction type emission element as a cold cathode element thereof is as follows.
For example, it is disclosed in U.S. Pat. No. 5,066,883. Such a flat-type electron beam display panel using a surface conduction electron-emitting device has been widely used at present.
It is possible to reduce the weight and increase the screen size as compared with T, and to achieve a higher height than other flat display panels such as a flat display panel using a liquid crystal, a plasma display, and an electroluminescent display. Brightness and high quality images can be provided.

FIG. 16 shows a conventional flat electron beam display panel as an example of an image forming apparatus using the electron-emitting device in a perspective view with a part thereof cut away. In the figure, reference numeral 1015 denotes a rear plate, 101
Reference numeral 7 denotes a face plate, and reference numeral 1016 denotes a side wall (support frame), and these constitute a vacuum envelope. Also,
Reference numeral 1011 denotes an electron source substrate, and 1012 denotes an electron-emitting device. In this case, one phosphor (described later) on a face plate 1017 corresponds to one electron-emitting device on the electron source substrate.

Reference numeral 1013 denotes a row-direction wiring,
Reference numeral 4 denotes a column-direction wiring, each of which is an electron-emitting device 101
2 are connected. Furthermore, 1019 is a metal back,
Reference numeral 1018 denotes a phosphor. Reference numeral 1020 denotes a spacer, which is a vacuum envelope as a supporting member that withstands atmospheric pressure so that the electron source substrate 1011 (in other words, the rear plate 1015) and the face plate 1017 maintain a predetermined interval from each other. Located inside.

In such an image forming apparatus, for example, a part of the electron beam incident on the image forming member (area) is scattered and collides with the surface of the spacer to emit secondary electrons. May be charged up so as to increase the potential. As a result, the potential distribution inside the vacuum envelope is distorted, and not only the trajectory of the electron beam becomes unstable, but also a discharge is generated inside the device, which may cause the device to be deteriorated or destroyed.

That is, since the charged portion has a higher potential and attracts electrons, the charge-up further proceeds, and a discharge is generated along the spacer. As a method for preventing charge-up of the spacer causing such discharge, a method of forming an antistatic film having an appropriate impedance on the spacer and removing the charge generated as described above can be applied. As this method, those described in JP-A-57-118355 and JP-A-61-124031 have already been proposed.

By the way, as in the conventional example shown in FIG.
13 and in the image forming area, an adhesive (not shown) for fixing the spacer
There is a problem that the gas generated from degrades the nearby surface conduction electron-emitting device, lowering the electron emission efficiency.
There is a problem that the antistatic film of the spacer is deteriorated to cause a local change in resistance value, thereby forming a unique electric field and distorting an image.

For this reason, a rectangular flat plate-shaped spacer (hereinafter, referred to as a long spacer) longer than at least one side of the image forming area is used to straddle the image forming area, and its extended end is fixed outside the area. A method of fixing with a member has been considered.

[0010]

However, in an image display device in which the long spacer is fixed to the rear plate and the face plate by using the fixing member, the face plate or the outside of the image forming area of the spacer is disposed. There is a case where there is a minute gap (void) without contacting the rear plate, and there is a problem that the minute gap triggers and a situation where discharge is easy occurs.

The present invention has been made on the basis of the above-mentioned circumstances, and its main object is to prevent discharge from occurring in a vacuum surrounding area using an electron source substrate, and to enable high-luminance display of an image. To provide a simple image forming apparatus.

[0012]

Therefore, in the present invention,
A rear plate having an electron source substrate on which an electron source is arranged, a face plate having an image forming area for forming an image by being irradiated with electrons emitted from the electron source, the rear plate and the face plate; A supporting frame for fixing the rear plate, a spacer disposed between the rear plate and the face plate for an atmospheric pressure resistant structure, the rear plate, the face plate,
In the image forming apparatus that forms a rectangular envelope that maintains a vacuum with the support frame and the spacer, the spacer straddles the image forming region in the envelope, and the end of the spacer is the An elongated flat plate extending out of the image forming area, and with respect to a surface of the spacer that stands on each surface of the rear plate and the face plate,
The upright width is substantially equal to the distance d between the face plate and the rear plate in the image forming area,
Further, the shape is smaller than the distance: d outside the image forming area, and its extended end is fixed to the face plate or the rear plate by a fixing member outside the image forming area. It is characterized by having been done.

With such a configuration, the discharge due to the minute gap between the spacer and the face plate or the minute gap between the spacer and the rear plate is eliminated, and it is difficult to discharge, and an image forming apparatus capable of displaying an image with high luminance can be obtained. it can.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be specifically described below. FIGS. 1, 3 to 6 show cross sections of a main part according to each embodiment of the present invention. FIG. 7 shows a cross-sectional plane of the envelope housing common to them, and FIG. 8 shows a plane of a fixing member as a part thereof. FIG. 9 is a partially broken perspective view of an envelope housing represented by the first embodiment.

In the figure, reference numeral 1015 denotes a rear plate, 10
Reference numeral 16 denotes a side wall (support frame) and 1017 denotes a face plate. These members 1015 to 1017 constitute an airtight container (vacuum envelope) for maintaining the inside of the display panel at a vacuum.

When assembling the hermetic container, a sealing means is used in order to maintain a sufficient strength and airtightness at a joint portion of each member.
A method can be adopted in which frit glass is applied to the joint portion and baked in air or a nitrogen atmosphere at a temperature of 400 to 500 degrees Celsius for 10 minutes or more.

The method for evacuating the inside of the airtight container will be described later. Further, the inside of the airtight container is 10
^-6 [Torr] is maintained in a vacuum, so that the airtight container is prevented from being destroyed due to the atmospheric pressure, an unexpected impact, or the like.
0 is provided.

Next, an electron-emitting device substrate (power supply substrate) that can be used in the image forming apparatus of the present invention will be described. This substrate is used as a rear plate 1015 constituting a container.
And is formed by arranging a plurality of cold cathode elements on the substrate 1011.

In the method of arranging the cold-cathode elements, the cold-cathode elements are arranged in parallel, and both ends of each element are connected by wiring.
A so-called ladder-type arrangement (hereinafter, referred to as a ladder-type arrangement electron source substrate) or a simple matrix arrangement (hereinafter, referred to as a matrix) in which a pair of element electrodes of a cold cathode element are connected to X-direction wiring and Y-direction wiring, respectively. (Referred to as a mold arrangement electron source substrate).

Note that an image forming apparatus having a ladder-shaped electron source substrate requires a control electrode (grid electrode) that controls the flight of electrons from the electron-emitting devices. Here, N × M cold cathode elements 1012 are formed on the substrate 1011. Note that 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 an image forming apparatus for displaying high-definition television, N = 3000 and M = 1
It is desirable to set the number to 000 or more. N × M
In each of the cold cathode elements, a simple matrix wiring is formed by M row-directional wirings 1013 and N column-directional wirings 1014. The portion constituted by the members 1011 to 1014 is called a multi-electron beam source.

The multi-electron beam source used in the image display device according to the present invention comprises a cold cathode element having a simple matrix wiring,
Alternatively, as long as the electron source has a ladder-type arrangement, there is no limitation on the material and shape of the cold cathode device or the manufacturing method thereof. Therefore, for example, a surface conduction type emission element or FE
, Or a cold cathode element such as an MIM type can be used.

Next, the structure of a multi-electron beam source in which surface conduction emission devices are arranged as cold cathode devices on a substrate and arranged in a simple matrix will be described.

FIG. 12 is a plan view of the multi-electron beam source used for the display panel of FIG. Here, surface conduction electron-emitting devices are arranged on a substrate 1011,
These elements include a row-directional wiring 1013 and a column-directional wiring 1013.
14, wiring is performed in a simple matrix. In addition, an insulating layer (not shown) is formed between the electrodes at a portion where the row direction wiring 1013 and the column direction wiring 1014 intersect, so that electrical insulation is maintained.

FIG. 13 shows a cross section taken along the line BB 'of FIG. Note that the multi-electron source having such a structure is provided in advance with a row-directional wiring 1013 and a column-directional wiring 1 on a substrate.
014, the inter-electrode insulating layer (not shown), and the device electrode and the conductive thin film of the surface conduction electron-emitting device, respectively, and then the row direction wiring 1013 and the column direction wiring 101
The device is manufactured by supplying power to each element through the device 4 and performing a current forming process and a current activation process.

In this embodiment, the substrate 101 of the multi-electron beam source is provided on the rear plate 1015 of the hermetic container.
1 is fixed, but when the substrate 1011 has a sufficient strength, the substrate 1011 of the multi-electron beam source itself may be used as the rear plate of the airtight container.

On the lower surface of the face plate 1017, a fluorescent film 1018 is formed. Here, since the display device is a color device, phosphors of three primary colors of red, green, and blue, which are generally used in the field of CRT, are separately applied to the portion of the fluorescent film 1018. Then, the phosphors of each color are separately applied in a stripe shape, for example, as shown in FIG. Black conductors 1010 are provided between the phosphor stripes.

Here, the purpose of providing the black conductor 1010 is that even if the irradiation position of the electron beam is slightly shifted,
The purpose is to prevent a shift in display color, prevent reflection of external light to prevent a decrease in display contrast, and prevent charge-up of a fluorescent film by an electron beam. Although graphite is used as the main component for the black conductor 1010, any other material may be used as long as it is suitable for the above purpose.

The method of applying the phosphors of the three primary colors is not limited to the stripe arrangement shown in FIG. 10A. For example, similarly, as shown in FIG. A delta-like array and other arrays (for example, FIG.
See also).

When a monochrome display panel is formed, a monochromatic phosphor material may be used for the phosphor film 1018, and it is needless to say that a black conductive material is not necessarily used.

A metal back 1019, which is generally known in the field of CRT, is provided on the surface of the fluorescent film 1018 on the rear plate side (ie, the inner surface of the airtight container). The purpose of providing the metal back 1019 is to improve the light utilization rate by mirror-reflecting a part of the light emitted from the fluorescent film 1018, to protect the fluorescent film 1018 from the collision of negative ions, and to increase the electron beam acceleration voltage. To act as an electrode for applying an electric field, and to act as a conductive path for excited electrons of the fluorescent film 1018.

The metal back 1019 is a fluorescent film 1018
Is formed on the face plate substrate 1017, the surface of the fluorescent film is smoothed, and Al is vacuum-deposited thereon. When a fluorescent material for low voltage is used for the fluorescent film 1018, the metal back 1010
19 is not used.

Although not used in the present embodiment,
For the purpose of applying acceleration voltage and improving the conductivity of the fluorescent film,
For example, a transparent electrode made of ITO may be provided between the face plate substrate 1017 and the fluorescent film 1018.

FIG. 14 is a schematic cross-sectional view taken along the line AA ′ of FIG. 9, and the numbers of the respective parts correspond to those used in FIG. Here, the spacer 1020 is formed by depositing a high-resistance film 11 for the purpose of preventing static electricity on the surface of the insulating member 1, and furthermore, this spacer is provided inside the face plate 1017 (such as a metal back 1019). The low resistance film 21 is formed on the side surface 5 of the high resistance film 11 having the contact surface 3 facing the surface of the substrate 1011 (the row wiring 1013 or the column wiring 1014). ing. Here, the spacers 1020 are arranged in the hermetic container at a required interval by a necessary number to achieve the purpose as a member for maintaining the atmospheric pressure resistant structure.

Particularly, in this embodiment, the spacer 10
Reference numeral 20 is fixed to the inside of the face plate and the surface of the substrate 1011 by a bonding material (not shown).
The high-resistance film is formed on the surface of the insulating member 1, at least in the airtight container, on the surface exposed to vacuum, and the low-resistance film 21 on the spacer 1020 and the bonding material are formed. Through this, it is electrically connected to the inside of the face plate 1017 (such as the metal back 1019) and the surface of the substrate 1011 (the row wiring 1013 or the column wiring 1014).

In the embodiment described here,
The spacer 1020 has a thin plate shape, is arranged in parallel with the row wiring 1013, and is electrically connected to the row wiring 1013. In particular, as the spacer 1020 in the image forming apparatus according to the present invention, the spacer 1020 only withstands a high voltage applied between the row direction wiring 1013 and the column direction wiring 1014 on the substrate 1011 and the metal back 1019 on the inner surface of the face plate 1017. It is necessary to have an insulating property and a conductive property enough to prevent the surface of the spacer 1020 from being charged.

The configuration for this will be described in each embodiment described later. The spacer 102
For example, quartz glass, Na
And ceramic members such as glass, soda lime glass, and alumina with a reduced impurity content.
The insulating member 1 preferably has a coefficient of thermal expansion close to that of the member forming the airtight container and the substrate 1011.

The high-resistance film 11 forming the spacer 1020 has an acceleration voltage Va applied to the face plate 1017 (metal back 1019 or the like) on the high potential side.
Is divided by the resistance value Rs of the high resistance film 11 serving as an antistatic film, and a current flows.

Therefore, the resistance value Rs of the spacer is set to a desirable range in terms of antistatic and power consumption. Further, the surface resistance is preferably 10 ¹⁴ Ω □ or less from the viewpoint of antistatic, and more preferably 10 ¹¹ Ω □ or less to obtain a sufficient antistatic effect. The lower limit of the surface resistance here depends on the shape of the spacer and the voltage applied between the spacers, but is preferably 10 ⁷ Ω □ or more.

The thickness t of the antistatic film formed on the insulating material is preferably in the range of 10 nm to 1 μm. This depends on the surface energy of the material, the adhesion to the substrate, and the substrate temperature, but in general, a thin film of 10 nm or less is formed in an island shape and has unstable resistance and poor reproducibility. When the thickness t is 1 μm or more, the film stress increases, the risk of film peeling increases, and the productivity is poor because the film formation time is prolonged.

Therefore, more preferably, the film thickness is 50 to 500.
nm. Here, surface resistance: R / □ is ρ
/ T, and from the preferred ranges of R / □ and t described above, the specific resistance ρ of the antistatic film is preferably 0.1 to 10 ⁸ Ωcm, and furthermore, a more preferable range of the surface resistance and the film thickness is realized. It is preferable that ρ is 10 ² to 10 ⁶ Ωcm.

As described above, the spacer is formed by current flowing through the antistatic film formed thereon or by heat generation during operation of the entire display.
Its temperature rises. If the resistance temperature coefficient of the antistatic film is a large negative value, the resistance value decreases when the temperature rises, the current flowing through the spacer increases, and the temperature further rises. As a result, the current continues to increase until the power supply limit is exceeded. The value of the temperature coefficient of resistance at which such runaway of current occurs is empirically a negative value, and the absolute value is 1% or more. That is, the temperature coefficient of resistance of the antistatic film is desirably greater than -1%.

As a material of the high resistance film 11 having antistatic properties, for example, a metal oxide can be used.
In particular, among metal oxides, oxides of chromium, nickel, and copper are preferred materials. The reason is that the secondary electron emission efficiency of these oxides is relatively small and the cold cathode device 10
It is considered that even when the electrons emitted from 12 hit the spacer 1020, they are difficult to be charged.

In addition to the metal oxides, for example,
Carbon is a preferable material because of its low secondary electron emission efficiency. In particular, since amorphous carbon has high resistance, it is easy to control the spacer resistance to a desired value.

As another material of the high resistance film 11 having the antistatic property, nitride of aluminum and a transition metal alloy is
By adjusting the composition of the transition metal, the resistance can be controlled in a wide range from a good conductor to an insulator. This is a stable material having a small change in resistance in a manufacturing process of a display device described later, and has a temperature coefficient of resistance of more than -1%, and is practically easy to use. In addition, as a transition metal element, Ti, Cr, Ta, etc. are mentioned.

The alloy nitride film is formed on the insulating member by thin film forming means such as sputtering, reactive sputtering in a nitrogen gas atmosphere, electron beam evaporation, ion plating, and ion assisted evaporation. The metal oxide film can also be formed by a similar thin film formation method. In this case,
Oxygen gas is used instead of nitrogen gas. Other, CVD
A metal oxide film can also be formed by a method or an alkoxide coating method.

The carbon film is formed by vapor deposition, sputtering, CV
D method, can be produced by plasma CVD method, especially,
In the case of forming amorphous carbon, hydrogen is contained in an atmosphere during film formation, or a hydrocarbon gas is used as a film formation gas.

Low resistance film 21 constituting spacer 1020
A high-resistance side face plate 101
7 (metal back 1019, etc.) and the substrate 1011 (wirings 1013, 1014, etc.) on the low potential side.
It is called an intermediate electrode layer. This intermediate electrode layer can have a plurality of functions listed below. The high resistance film 11 is electrically connected to the face plate 1017 and the substrate 1011.

As described above, the high resistance film 11 is provided for the purpose of preventing charging on the surface of the spacer 1020.
7 (such as metal back 1019) and substrate 1011
(Wirings 1013, 1014, etc.) directly or via the contact material 1041, a large contact resistance may be generated at the interface of the connection portion, and the charge generated on the spacer surface may not be removed quickly. There is. In order to avoid this, a low-resistance intermediate electrode layer is provided on the contact surface 3 or the side surface 5 of the spacer 1020 that comes into contact with the face plate 1017, the substrate 1011 and the contact material 1041. The potential distribution of the high resistance film 11 is made uniform.

The electrons emitted from the cold cathode element 1012 form electron orbits in accordance with the potential distribution formed between the face plate 1017 and the substrate 1011. In order to prevent the electron orbit from being disturbed in the vicinity of the spacer 1020, it is necessary to control the potential distribution of the high resistance film 11 over the entire area. When the high resistance film 11 is connected directly to the face plate 1017 (such as the metal back 1019) and the substrate 1011 (such as the wirings 1013 and 1014) or via the contact material 1041, the contact resistance at the interface of the connection portion is reduced. In addition, the connection state may be uneven, and the potential distribution of the high resistance film 11 may deviate from a desired value. In order to avoid this, a low-resistance intermediate electrode layer is provided in the entire length region of the spacer end (contact surface 3 or side surface 5) where the spacer 1020 contacts the face plate 1017 and the substrate 1011. By applying a desired potential to the location, the potential of the entire high resistance film 11 can be controlled. Controls the trajectory of emitted electrons.

Electrons emitted from the cold cathode element 1012 form electron orbits in accordance with the potential distribution formed between the face plate 1017 and the substrate 1011. Regarding the electrons emitted from the cold cathode devices near the spacers, there may be restrictions (such as changes in wiring and device positions) associated with the installation of the spacers. In such a case, in order to form an image without distortion or unevenness, it is necessary to control the trajectory of the emitted electrons and irradiate a desired position on the face plate 1017 with the electrons. Face plate 101
By providing a low-resistance intermediate electrode layer on the surface (side surface portion 5) in contact with the substrate 10 and the substrate 1011
By giving desired characteristics to the potential distribution near zero, the trajectory of emitted electrons can be controlled.

The low-resistance film 21 may be made of a material having a sufficiently lower resistance than the high-resistance film 11, and may be made of Ni, Cr, Au, Mo, W, Pt, Ti, Al, Cu, Pd, etc.
Metals or their alloys, and Pd, Ag, Au, RuO ₂ , Pd
Such -ag, such as from configured printing conductive metal or metal oxide and glass or, such as In ₂ O ₃ -SnO _2, a semiconductor material such as a transparent conductor and polysilicon, can be appropriately selected .

The bonding material 1041 includes a spacer 10
20 is a row direction wiring 1013 and a metal back 1019
It is necessary to impart conductivity so as to be electrically connected to the substrate. Therefore, frit glass to which a conductive adhesive, metal particles, or a conductive filler is added is preferable.

The symbols Dx1 to Dxm and Dy1 to Dy1
Dyn and Hv are electric connection terminals having a hermetic structure configured to penetrate a side wall (support frame) 1016 in order to electrically connect the display panel and an electric circuit (not shown). is there. The terminals Dx1 to Dxm are connected to the row wiring 1013 of the multi-electron beam source and the terminals Dy1 to Dyn.
Is the column-directional wiring 1014 of the multi-electron beam source, the terminal Hv is the metal back 1019 of the face plate,
Each is electrically connected.

To evacuate the inside of the hermetic container, after assembling the hermetic container, an exhaust pipe and a vacuum pump (both not shown) are connected, and the inside of the hermetic container is about 10 ^-7 [Torr]. Evacuate to a vacuum. Thereafter, the exhaust pipe is sealed, but a getter film (not shown) is formed at a predetermined position in the airtight container immediately before or after the sealing in order to maintain the degree of vacuum in the airtight container. The getter film is, for example,
It is a film formed by heating and depositing a getter material containing Ba as a main component by a heater or high-frequency heating, and the inside of the airtight container is 10 ⁻⁵ due to the adsorption action of the getter film.
Alternatively, the degree of vacuum is maintained at 10 ^-7 [Torr].

In the image display device using the display panel described above, the terminals Dx1 to Dxm outside the container, and
When a voltage is applied to each cold cathode element 1012 through Dy1 to Dyn, electrons are emitted from each cold cathode element 1012. At the same time, a high voltage of several hundred [V] to several [kV] is applied to the metal back 1019 through the external terminal Hv to accelerate the above-mentioned emitted electrons and collide with the inner surface of the face plate 1017. Thereby, the phosphors of each color forming the fluorescent film 1018 are excited and emit light,
Display an image.

The voltage applied to the surface conduction electron-emitting device 1012 of the present invention, which is usually a cold cathode device, is 12 to 1
The distance d between the metal back 1019 and the cold cathode element 1012 is from 0.1 [mm] to 8 [m].
m], metal back 1019 and cold cathode element 1012
Is about 0.1 [kV] to about 10 [kV].

The basic configuration of the display panel, its manufacturing method, and the outline of the image display device according to the embodiment of the present invention have been described above. Next, main features of the present invention will be described.

According to the present invention, the rear plate 101 having the electron source substrate 1011 on which the electron sources are arranged as described above.
5, a face plate 1017 having an image forming area for forming an image by irradiation of electrons emitted from the electron source, a support frame 1016 for fixing the rear plate and the face plate, A spacer 1020 is disposed between the rear plate and the face plate for an atmospheric pressure resistant structure. The rear plate, the face plate, the support frame, and the spacer form a rectangular envelope that maintains a vacuum. Make up.

In the image forming apparatus using the envelope, the spacer 1020 extends across the image forming area and extends outside the image forming area in the envelope. An elongate flat plate (extended length = a), and with respect to the surface of the spacer 1020 which stands up to the respective surfaces of the rear plate and the face plate, its upright width is within the image forming area by the face plate and the rear plate. And the distance d is substantially equal to d outside the image forming area, and is smaller than the distance d. It is fixed by the fixing member 50 outside the image forming area.

(First Embodiment) A case where an electric field is determined by a current field will be described below. Here, reference numeral 1015 denotes a rear plate including an electron source substrate, 1016 denotes a side wall (support frame), 1017 denotes a face plate, 1018 denotes a phosphor, 1019 denotes a metal back, 1020 denotes a spacer,
0 is a fixing member.

The face plate 1017 and the rear plate are made of soda lime glass and
Reference numeral 16 is made of non-alkali glass. The surface of the spacer 1020 is coated with a high-resistance film and has conductivity. Further, since the spacer 1020 is installed on the row direction wiring (not shown) on the rear plate 1015 and extends over the entire image display area, there is no gap. Further, the extending end of the spacer 1020 is linearly inclined toward the rear plate outside the image forming area, and the entire spacer has a trapezoidal flat plate configuration.

In such a case, the soda lime glass of the face plate has a low resistance compared to the alkali-free glass of the side wall 1016, and even though there is no anode electrode, the soda lime glass is almost out of the image forming area of the face plate. A voltage equal to the anode voltage will be applied. However, in this embodiment, the spacer 1020 does not disturb the electric field and causes a high potential difference in the small gap as shown by the equipotential lines in the figure. There is nothing.

Therefore, as shown in FIG.
It is conventional (FIG. 2) that the extended end portion (outside the image forming area) 20 is formed obliquely and the entire spacer is formed as a trapezoidal flat plate.
) Is more effective in suppressing discharge. By the way, in the conventional device, the minute gap disturbs the electric field, and the longer the portion (extended end) outside the image forming area becomes,
In particular, a high potential difference is generated in the minute gap at the upper edge of the extension end of the spacer.

(Second Embodiment) As shown in FIG. 3, a portion (extending end) of the spacer 1020 outside the image forming area is formed by a slanted edge portion and a vertical edge portion (length = length). The combination with b), that is, the entire spacer may be a hexagonal flat plate. In this case, as shown by the equipotential lines in the figure, the electric field is slightly disturbed as compared with the case of the first embodiment, but a high potential difference still occurs in the minute gap as in the conventional example. There is no such thing.

(Third Embodiment) Further, as shown in FIG. 4, even if the portion (extending end) of the spacer 1020 outside the image forming region is inclined in an arc shape, As indicated by the line, slightly more than in the first embodiment,
Although the electric field is disturbed, a high potential difference does not occur in the minute gap unlike the conventional example.

(Fourth Embodiment) Next, a case where an electric field is determined by an electrostatic field will be described. As shown in FIG. 5, reference numeral 1015 denotes a rear plate including an electron source substrate,
1016 is a side wall (support frame), 1017 is a face plate, 1018 is a phosphor, 1019 is a metal back,
20 is a spacer and 50 is a fixing member. Here, the face plate 1017 and the rear plate are made of soda lime glass, and the side wall 1016 and the spacer 1010
Reference numeral 20 is made of non-alkali glass and has no high resistance film. Further, the spacer 1020 is provided on the rear plate 101.
No. 5 is provided on the row-direction wiring (not shown) and extends over the entire image forming area. The extending end (length = a) of the spacer 1020 has a step (rectangular width of the extending end = extending end = d ₀ ) cut into a rectangle from the end of the image forming area. d ₁ )
The entire spacer is a convex flat plate.

FIG. 15 shows a conventional example as a comparative example with respect to this embodiment. According to this conventional example, assuming that the dielectric constant in vacuum is ε ₀ , the relative dielectric constant of the spacer member is ε ₁ , the electric field of the minute gap is E ₀ , and the electric field applied to the spacer member is E ₁ , ε ₀ E ₀ = ε ₁ ε ₀ E ₁ to E ₀ =
epsilon ₁ E ₁ becomes, the minute gap (d _0), ε ₁ times the electric field of the electric field exerted between the spacer vertically consuming. When the spacer is made of glass, an electric field several times higher is applied.

In contrast, in this embodiment, the gear
(D₀) Is spread, so the electric field concentration can be reduced
You. Preferably, the distance d in FIG.₀And d₁D₀=
ε₁d ₁Close to the gap, the voltage between the gap and the top and bottom of the spacer
The world stabilizes.

(Fifth Embodiment) Further, as an embodiment of the present invention, as shown in FIG. 6, the extension end of the spacer outside the image formation area is connected to the rear plate side of the image formation area. It is also possible to use a spacer having a step (the rising width of the extended end portion = d ₁ ) having a rectangular cut (a gap with the rising width = d ₂ ) from the end. In this case, it can be effectively applied when the row direction wiring (not shown) is not linear over the inside and outside of the image forming area. If a high resistance film is applied to the spacer 1020 in the image forming area, the charge due to electron emission is reduced, which is even better.

[0071]

(Embodiment 1) Embodiment 1 will be specifically described with reference to FIGS. First, design dimensions are shown in FIG. The length A in the X direction of the image forming area 53 is 200 m
m, the length B of the extending end of the spacer from the image forming area 53 to the fixing member 50 is 10 mm, and the fixing member 50 and the support frame 10
16 was set to 10 mm.

The length D in the Y direction of the image forming area 53
Was set to 150 mm, and the length E between the image forming area 53 and the support frame 1016 was set to 20 mm. In addition, all these dimensional specifications are vertically and horizontally symmetrical in the drawings. The arrangement interval of the fixing members 50 is an integer multiple of 0.65 mm, which is the interval between the row wiring 1013 of the rear plate and the black stripe 1010 of the face plate, for example, 15.6 mm, and the spacer is arranged on the row wiring. I do. Note that the row direction wiring 1
The width of 013 was 0.3 mm, and the thickness of the spacer was 0.2 mm.

Next, the dimensions of the fixing member 50 will be described with reference to FIG. The thickness of the fixing member (not shown) is 0.5m
m, outer side F is 6mm, G is 5mm, diameter J of the hole at the bonding part is 3m
m, I representing the position of the hole was 3 mm, and the width H of the groove between the spacers was 0.25 mm. Also, the length of the spacer at this time is 23
0 mm.

As shown in FIG. 1, the extending end of the spacer is formed obliquely from the end of the anode electrode toward the rear plate. The size of the oblique portion is a = 15 mm in the figure.

The spacers used in this embodiment include:
The following processing has been performed. First, an intermediate electrode layer for electrically connecting to the face plate and the rear plate was formed in a vapor phase by sputtering. Intermediate electrode layer is 10 nm
It has a two-layer structure of a thick Ti film and a 200 nm thick Pt film, and the Ti film is a Pt film.
It was necessary as a base layer for reinforcing the film adhesion of the film. At this time, the thickness of the intermediate electrode layer is 210 nm, and the surface resistance is 10 nm.
Ω / □. Thereafter, a Cr-Al alloy nitride film having a thickness of 200 nm was formed on the substrate surface as an antistatic film by simultaneously sputtering Cr and Al targets with a high-frequency power supply. The sputtering gas at this time is a mixed gas of Ar: N ₂ in a ratio of 1: 2, and the total pressure is 1 mTorr. Under the above conditions, the sheet resistance of the film formed at the same time was 2 × 10 ¹⁰ Ω / □. However,
The intermediate electrode layer and the film are formed only in a region in contact with the anode electrode.

When the spacer was used, the gap at the portion (extended end) not in contact with the anode electrode was widened as compared with the case where a conventional rectangular flat plate was used, and it was substantially difficult to discharge. Specifically, in the conventional example, discharge may occur at a small gap, and it is difficult to stably display an image by inducing a discharge in the image forming region. At Va = 6 kV, discharge did not occur in a portion not in contact with the anode electrode, so that a high-luminance image could be stably displayed.

(Embodiment 2) This embodiment is different from Embodiment 1 in that, as shown in FIG. 3, a portion outside the image forming area (extending end portion) of the spacer has an oblique edge portion and a vertical edge portion. , That is, the entire spacer is a hexagonal flat plate. Here, in the figure, the symbols a and b are 15 mm and 1 mm, respectively.

In this embodiment, the same effect as that of the first embodiment can be obtained. At Va = 6 kV, there is no discharge outside the image forming area (extended end), and an image can be displayed stably. Was completed. Further, as compared with the first embodiment, there is no sharp portion (edge) at the distal end portion of the spacer, and the work can be easily performed at the time of fixing, so that the process time can be shortened.

(Embodiment 3) This embodiment is different from Embodiment 1 in that, as shown in FIG. 4, a portion between the spacer and the fixing member from the place where the spacer comes into contact with the anode electrode on the face plate side. (End) is a rounded shape.

Also in this embodiment, the same effect as in the first embodiment was obtained. At Va = 6 kV, there was no discharge outside the image forming area, and an image could be displayed stably. Further, compared to the first and second embodiments, the process time can be shortened because there is no sharp portion (edge) at the tip of the spacer, and the work is easy when fixing.

(Embodiment 4) In this embodiment, the spacer is made of non-alkali glass, and as shown in FIG.
Regarding the upright surface of the spacer (as viewed from the surface having the largest surface area), the portion outside the image forming area (extending end) has a rectangular stepped shape from the end of the image forming area. Thus, the entire spacer was a convex flat plate. Here, reference numeral 1015 denotes a rear plate including an electron source substrate, 1
016 is a side wall (support frame), 1017 is a face plate, 1018 is a phosphor, 1019 is a metal back,
20 is a spacer and 50 is a fixing member. Here, the face plate 1017 and the rear plate are made of soda lime glass, and the side wall 1016 and the spacer 1020 are made of non-alkali glass. Also, the spacer 102
0 is a row direction wiring on the rear plate 1015 (not shown)
Since it is installed in the entire area of the image forming area,
There are no gaps. In the figure, the length of a was 15 mm.

At this time, since the alkali-free glass has a higher resistance than soda lime, the electric field of the gap is determined by the dielectric constant. An image forming area outside of the upright width of the spacer (height) d ₁ = 1 mm, the gap d ₀ between the spacer face plate, d ₁ approximately 0.8mm, and the the height towards the narrow d ₀
An electric field several times the electric field applied is applied, but the electric field intensity is reduced by several tens of times as compared with the conventional minute gap, making it difficult to discharge.

(Embodiment 5) This embodiment is different from Embodiment 4 in that a high resistance film is formed in the image forming region of the spacer. Also in this case, there was no discharge outside the image forming area (the area where the extended ends of the spacers exist), and an image could be displayed stably. In addition, since the spacer is provided with a high-resistance film in the image forming region, the charge on the spacer surface due to electron emission is reduced, and the image distortion is improved.

Embodiment 6 In this embodiment, the spacer is made of non-alkali glass. As shown in FIG. 6, the upright surface of the spacer (as viewed from the surface having the largest surface area) is outside the image forming area. The portion (extended end) has a stepped shape with a rectangular notch on the face plate side and the rear plate side from the end of the image forming area. Here, reference numeral 1015 denotes a rear plate including an electron source substrate, 1016 denotes a side wall (support frame), 1017 denotes a face plate, 1018 denotes a phosphor, 1019 denotes a metal back, 1020 denotes a spacer, and 50 denotes a fixing member. Here, the face plate 1017 and the rear plate are made of soda lime glass, and the side wall 1016 and the spacer 1020 are made of non-alkali glass.

Further, in this embodiment, the row direction wiring (not shown) is linear in the image forming area, but is connected non-linearly outside the image forming area. Therefore, since the spacer 1020 is provided on the row direction wiring in the image forming area on the rear plate 1015,
There are no gaps. Moreover, in this embodiment, the height of the fixing member 50 is 1 mm, and the height of d ₁ is 0.4 mm and the height of d ₂ is 0.7 m in the drawing.
m.

At this time, the gap d ₀ between the spacer (extended end) and the face plate outside the image forming area is about 0.7 mm, and the electric field strengths d ₀ and d ₂ are stronger than d _1. However, since the minute gap can be eliminated particularly at the rear plate side where it does not come into contact with the row-direction wiring, the electric field intensity is reduced by several tens of times as compared with the conventional minute gap, making it difficult to discharge.

The shape of the extending end portion of the spacer according to the present invention is not limited to those shown in the above-described embodiments and examples, and may be any shape that eliminates a minute gap. Of course, the shape may be sufficient.

[0088]

As described above, according to the present invention,
An image forming apparatus having a high discharge withstand voltage can be provided.
Further, in the present invention, it is possible to save space outside the image display area.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a spacer fixing portion according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a conventional spacer fixing portion shown in comparison with the present invention.

FIG. 3 is a configuration diagram of a spacer fixing portion according to a second embodiment of the present invention.

FIG. 4 is a configuration diagram of a spacer fixing portion according to a third embodiment of the present invention.

FIG. 5 is a configuration diagram of a spacer fixing portion according to a fourth embodiment of the present invention.

FIG. 6 is a configuration diagram of a spacer fixing portion according to a fifth embodiment of the present invention.

FIG. 7 is a configuration diagram of the image forming apparatus according to the embodiment of the present invention in plan view.

FIG. 8 is a plan view of a fixing member according to an embodiment of the present invention.

FIG. 9 is a perspective view in which a part of the display panel is cut away in the embodiment of the present invention.

FIG. 10 is a plan view illustrating a phosphor array of a face plate of a display panel.

FIG. 11 is a plan view similarly illustrating a color arrangement.

FIG. 12 is a plan view of a substrate of the multi-electron beam source.

FIG. 13 is a partial cross-sectional view of a substrate of the multi-electron beam source.

FIG. 14 is a cross-sectional view taken along the line AA ′ of the display panel.

FIG. 15 is a configuration diagram of a spacer fixing portion for explaining a gap in a conventional example.

FIG. 16 is a perspective view of a display panel of a conventional example with a part cut away.

[Description of Signs] 1 Spacer substrate 3 Contact surface of spacer facing electron source substrate 5 Side surface of spacer in contact with electron source substrate 11 High resistance film 21 Low resistance film 31a Phosphor 31b Black conductor 40 Interlayer insulating layer 50 Fixed Member 1011 Power supply board 1012 Cold cathode element 1013 Row wiring 1014 Column wiring 1015 Rear plate 1016 Side wall (support frame) 1017 Face plate 1018 Phosphor 1019 Metal back 1020 Spacer 1102, 1103 Device electrode 1104 Conductive thin film 1105 Electron emitting section 1113 Thin film 1010 Black conductive material 1041 Bonding material

Claims (16)

[Claims] A rear plate having an electron source substrate on which an electron source is arranged; a face plate having an image forming area for forming an image by irradiating electrons emitted from the electron source; and the rear plate. And a support frame for fixing the face plate, and a spacer disposed between the rear plate and the face plate for an atmospheric pressure resistant structure, the rear plate, the face plate, the support frame, and In the image forming apparatus which forms a rectangular envelope that maintains a vacuum with a spacer, the spacer straddles the image forming region in the envelope, and ends its end with the image forming region. An elongate flat plate extending outwardly, with respect to the surface of the spacer standing on each surface of the rear plate and the face plate. Width, the distance between the image forming the face plate and the rear plate in the area: approximately equal to d, also, in the image forming area outside that distance: d
It is a smaller shape, the extending end of which is
An image forming apparatus, wherein the image forming apparatus is fixed to the face plate or the rear plate by a fixing member outside an image forming area. 2. The image forming apparatus according to claim 1, wherein the spacer is fixed to the rear plate, and an extended end of the spacer is located on the rear plate side outside the image forming area with respect to a rising surface. An image forming apparatus characterized by being linearly inclined. 3. The image forming apparatus according to claim 1, wherein the spacer is fixed to the rear plate, and an extended end of the spacer is located outside the image forming region on the rear plate side with respect to a rising surface. An image forming apparatus characterized by being inclined while drawing an arc. 4. The image forming apparatus according to claim 1, wherein the spacer is fixed to the rear plate, and a rising width of an extending end of the spacer outside the image forming region is larger than a rising width in the region. So that its extended end is
An image forming apparatus, wherein the image forming apparatus is formed with a step on the face plate side. 5. The image forming apparatus according to claim 1, wherein the spacer is fixed to the rear plate, and a rising width of an extending end of the spacer outside the image forming region is larger than a rising width in the region. So that its extended end is
An image forming apparatus, wherein the face plate and the rear plate are formed with a step. 6. The spacer according to claim 1, wherein the spacer is fixed by an adhesive.
Item 10. The image forming apparatus according to item 1. 7. The image forming apparatus according to claim 1, wherein the spacer is fixed by frit glass. 8. The image forming apparatus according to claim 1, wherein the spacer is conductive. 9. The image forming apparatus according to claim 8, wherein the spacer has a high resistance film formed on a surface thereof. 10. The high-resistance film has a surface resistance of 10 ^7.
The image forming apparatus according to claim 9, wherein the value is from 10 to 10 ¹⁴ Ω / □. 11. The high-resistance film is provided through a low-resistance film,
The image forming apparatus according to claim 9, wherein the image forming apparatus is electrically connected to the face plate and the rear plate. 12. The image forming apparatus according to claim 11, wherein the low resistance film has a surface resistance value that is at least one digit lower than a resistance value of the high resistance film. 13. The image forming apparatus according to claim 4, wherein the spacer is configured to maintain insulation. 14. The image forming apparatus according to claim 4, wherein the spacer is configured to maintain its insulating property outside the image forming area. 15. The image forming apparatus according to claim 1, wherein the electron source is a cold cathode device. 16. The image forming apparatus according to claim 15, wherein said electron source is a surface conduction electron-emitting device.