JP3466848B2 - Image display device - Google Patents

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 supporting member (spacer) inside an envelope of the image forming apparatus. .

[0002]

2. Description of the Related Art Conventionally, two types of electron-emitting devices, known as a hot cathode device and a cold cathode device, are known. Among them, as the cold cathode device, for example, a surface conduction type emission device, a field emission type device (hereinafter referred to as FE type), a metal / insulating layer / metal type emission device (hereinafter referred to as MIM type), etc. are known. There is.

As the surface conduction electron-emitting device, for example,
M. I. Elinson, Radio Eng. Ele
ctron Phys. , 10, 1290, (196
5) and other examples described later are known.

The surface conduction electron-emitting device utilizes a phenomenon in which electron emission occurs when a current is passed through a thin film having a small area formed on a substrate in parallel with the film surface. The surface conduction electron-emitting device includes Sn by Erlinson et al.
Besides an O2 thin film, an Au thin film [G. Dittmer: "Thin Solid Fi
lms ”, 9, 317 (1972)], In2O3 / S
nO2 thin film [M. Hartwell and
C. G. Fonstad: "IEEE Trans.
ED Conf. , 519 (1975)] and carbon thin film [Hiraki Araki et al .: Vacuum, Vol. 26, No. 1]
No., 22 (1983)] and the like.

As a typical example of the element structure of these surface conduction electron-emitting devices, FIG. Hartwell
FIG. In the figure, 3001
Is a substrate, and 3004 is a conductive thin film made of metal oxide formed by sputtering. The conductive thin film 3004 is formed in an H-shaped plane shape as illustrated. An electron-emitting portion 3005 is formed by subjecting the conductive thin film 3004 to an energization process called energization forming described later. In the figure, the interval L is 0.5 to 1 [mm], and W is 0.
It is set to 1 [mm]. For convenience of illustration, the electron emitting portion 3005 is shown in a rectangular shape in the center of the conductive thin film 3004, but this is a schematic one, and the actual position and shape of the electron emitting portion is faithfully expressed. It doesn't mean that.

M. In the above-mentioned surface conduction electron-emitting device including the device by Hartwell et al., The electron-emitting portion 3005 is formed by performing an energization process called energization forming on the conductive thin film 3004 before the electron emission.
Was commonly formed. That is, the energization fo
Muming means that a constant DC voltage or a DC voltage boosted at a very slow rate of, for example, about 1 V / min is applied to both ends of the conductive thin film 3004 to conduct electricity.
The conductive thin film 3004 is locally destroyed, deformed, or altered so that the electron emitting portion 30 is in an electrically high resistance state.
05 is to be formed. In addition, in a part of the conductive thin film 3004 which is locally destroyed, deformed or altered,
A crack occurs. When an appropriate voltage is applied to the conductive thin film 3004 after the energization forming, electrons are emitted near the crack.

An example of the FE type is disclosed in W. P.
Dyke & W. W. Dolan, "Field Emi
ssion ”, Advance in Electron
Physics, 8, 89 (1956), or
C. A. Spindt, "Physical prop
erties of thin-film field
Mission cathodes with molly
bdenium cones ", J. Appl. Phy
s. , 47, 5248 (1976) and the like are known.

As a typical example of the FE type element structure, FIG. A. 3 shows a cross-sectional view of the device by Spindt et al. In the figure, 3010 is a substrate, 3011 is an emitter wiring made of a conductive material, 3012 is an emitter cone, 3013 is an insulating layer, and 3014 is a gate electrode. This device has an emitter cone 3012 and a gate electrode 3
By applying an appropriate voltage during 014, field emission is caused from the tip of the emitter cone 3012.

As another element structure of the FE type, as shown in FIG.
There is also an example in which the emitter and the gate electrode are arranged on the substrate substantially parallel to the substrate plane, instead of the above laminated structure.

As an example of the MIM type, for example,
C. A. Mead, "Operation of tun
nel-emission Devices, J. Ap
pl. Phys. , 32,646 (1961) and the like are known. A typical example of the MIM type device configuration is shown in FIG. The figure is a cross-sectional view. In the figure, 3020 is a substrate, 3021 is a lower electrode made of metal, 3022 is a thin insulating layer having a thickness of about 100 Å, and 3023 is a thickness of about 80 to 300 Å. The upper electrode is made of metal. In the MIM type, electrons are emitted from the surface of the upper electrode 3023 by applying an appropriate voltage between the upper electrode 3023 and the lower electrode 3021.

The above-mentioned cold cathode device can obtain electron emission at a lower temperature than the hot cathode device, so that it can be used as a heating heater.
No need for a tar. Therefore, the structure is simpler than that of the hot cathode device, and a fine device can be manufactured. Also,
Even if a large number of elements are arranged on the substrate at a high density, problems such as heat melting of the substrate hardly occur. In addition, the response speed is slow because the hot cathode element operates by heating the heater, and the cold cathode element has an advantage that the response speed is fast.

Therefore, researches for applying the cold cathode device have been actively conducted.

For example, the surface conduction electron-emitting device has an advantage that a large number of devices can be formed over a large area because it has a particularly simple structure and is easy to manufacture among cold cathode devices. Therefore, for example, JP-A-64-31 by the present applicant
Methods for arranging and driving a large number of devices have been investigated, as disclosed at 332. For application of the surface conduction electron-emitting device, for example, image forming devices such as image display devices and image recording devices, and charged beam sources have been studied.

Particularly, as an application to an image display device, for example, US Patent Publication USP 5,066,
883, JP-A-2-257551, and JP-A-4-4-2.
As disclosed in Japanese Patent No. 8137, an image display device using a combination of a surface conduction electron-emitting device and a phosphor that emits light upon irradiation with an electron beam has been studied. An image display device using a combination of a surface conduction electron-emitting device and a phosphor is expected to have better characteristics than other conventional image display devices. For example, it can be said that it is superior in that it does not require a backlight because it is a self-luminous type and has a wide viewing angle, even compared with a liquid crystal display device that has become widespread in recent years.

A method for driving a large number of FE types is described in, for example, USP 4,904,89 by the present applicant.
5 are disclosed. Further, as an example in which the FE type is applied to an image display device, for example, R.I. A flat panel display device reported by Meyer et al. Is known. [R. Me
yer: "Recent Development on
Microtips Display at LET
I ", Tech. Digest of 4th Int.
Vacuum Microelectronics C
onf. , Nagahama, pp. 6-9 (199
1)]

An example in which a large number of MIM types are arranged and applied to an image display device is disclosed in, for example, Japanese Patent Application Laid-Open No.
It is disclosed in Japanese Patent No. 55738.

Among the image forming apparatuses using the electron-emitting devices as described above, the flat-panel display device having a small depth is space-saving and lightweight, and thus is attracting attention as a replacement for the cathode ray tube display device. .

FIG. 5 is a perspective view showing an example of a display panel portion forming a flat image display device, and a part of the panel is cut away to show the internal structure.

In the figure, 3115 is a rear plate and 3116.
Is a side wall, 3117 is a face plate, and the rear plate 3115, the side wall 3116, and the fuse plate 3
117 forms an envelope (airtight container) for maintaining a vacuum inside the display panel.

A substrate 3111 is fixed to the rear plate 3115, and N × M cold cathode elements 3112 are formed on the substrate 3111. (N and M are positive integers of 2 or more, and are appropriately set according to the target number of display pixels.) Further, the N × M cold cathode elements 31.
As shown in FIG. 5, reference numeral 12 denotes M row-direction wirings 3113.
And N column-direction wirings 3114. These substrates 3111, cold cathode elements 3112, row-direction wiring 3
A portion constituted by 113 and column-direction wiring 3114 is called a multi-electron beam source. In addition, the row wiring 31
An insulating layer (not shown) is formed between the wirings 13 and at least the column-direction wirings 3114 so as to intersect each other so that electrical insulation is maintained.

A phosphor film 3118 made of a phosphor is formed on the lower surface of the face plate 3117, and a phosphor (not shown) of three primary colors of red (R), green (G), and nurturing (B) is applied. It is divided. A black body (not shown) is provided between the phosphors of the respective colors forming the phosphor film 3118, and a metal back 3119 made of Al or the like is formed on the rear plate 3115 side surface of the phosphor film 3118. ing.

Dx1 to Dxm and Dy1 to Dyn and Hv are electric connection terminals of an airtight structure provided for electrically connecting the display panel and an electric circuit (not shown). Dx1 to Dxm are electrically connected to the row-directional wiring 3113 of the multi-electron beam source, Dy1 to Dyn are electrically connected to the column-directional wiring 3114 of the multi-electron beam source, and Hv is electrically connected to the metal back 3119.

Further, the inside of the airtight container is held in a vacuum of about 10 <-6> Torr, and as the display area of the image display device increases, the rear plate 3115 due to the pressure difference between the inside and the outside of the airtight container. And a means for preventing the deformation or destruction of the face plate 3117 is required. The method of thickening the rear plate 3115 and the face plate 3116 not only increases the weight of the image display device but also causes image distortion and parallax when viewed from an oblique direction. On the other hand, in FIG. 5, a structural support (called a spacer or a rib) 3120 made of a relatively thin glass plate for supporting atmospheric pressure is provided. In this way, the substrate 3111 on which the multi-beam electron source is formed and the fluorescent film 31.
The space between the face plates 3116 formed with 18 is usually kept to a submillimeter to several millimeters, and as described above, the inside of the airtight container is kept at a high vacuum.

In the image display device using the display panel described above, when a voltage is applied to each cold cathode element 3112 through the terminals Dx1 to Dxm and Dy1 to Dyn outside the container, electrons are emitted from each cold cathode element 3112. At the same time, a high voltage of several hundred [V] to several [kV] is applied to the metal back 3119 through the terminal Hv outside the container to accelerate the emitted electrons to collide with the inner surface of the face plate 3117. As a result, the phosphors of the respective colors forming the phosphor film 3118 are excited and emit light, and an image is displayed.

[0025]

The electron beam apparatus such as the image forming apparatus described above includes an envelope for maintaining a vacuum atmosphere inside the apparatus, an electron source arranged in the envelope, It has a target irradiated with an electron beam emitted from an electron source, an acceleration electrode for accelerating the electron beam toward the target, and the like, and further for supporting the atmospheric pressure applied to the envelope from the inside of the envelope. A support member (spacer) may be arranged inside the envelope.

Here, description will be given with reference to FIG. 7, which is a basic configuration diagram of the image forming apparatus taken along the line AA 'in FIG. 11
Is a substrate, 15 is a rear plate, 16 is a side wall, and 17 is a face plate. Together, 15, 16, 17 form an envelope. Reference numeral 20 is a spacer, 18 is a phosphor, 19 is a conductive member (metal back), and 13 is a scanning signal wiring. An element 111 is formed on the substrate 11, and an electron beam 112 is emitted from the element 111 to form an image on the phosphor 18. Va is the anode voltage, Vf '
Is a voltage applied so that the voltage applied to the non-driven element does not exceed the electron emission threshold voltage Vth as shown in FIG.

However, if a scanning signal is applied to 1 of the scanning signal wiring 13 (for example, 0 V) to drive the element 111 and becomes lower than the potential (Vf ′) of 2 of the other scanning signal wiring 13, The electron beam 112 emitted from the element 111 adjacent to the scanning signal wiring on which the spacer is mounted is inclined to the second side of the scanning signal wiring 13 adjacent to the element 111 having a high potential. As a result, the electron beam collides with the spacer and is blocked, which may cause a decrease in brightness in the vicinity of the spacer.

Therefore, an object of the present invention is to provide an image forming apparatus using an electron beam, in which a decrease in the brightness of the electron beam on the target (phosphor) surface is prevented.

[0029]

Therefore, there is a problem in that the electrons emitted from the electron-emitting device collide with the surface of the supporting member (spacer) and are blocked, so that the brightness of the phosphor near the supporting member decreases. The following measures were taken to solve the problem.

(1) In the present invention, a plurality of electron-emitting devices are connected to each, and scanning for applying a selection voltage and a non-selection voltage smaller than the selection voltage to the plurality of electron-emitting devices. If the plurality of signal wirings are
The output element is located on the same side of each scanning signal wiring.
A plurality of scanning signal wirings arranged on the substrate
Have the same interval and are connected to each scan signal wiring
An electron source in which the distances between the electron emitting devices are the same ,
A face plate arranged facing the substrate and having an acceleration electrode for accelerating an electron beam; and a support member arranged between the substrate and the face plate and on the scan signal wiring. In the image forming apparatus having, the center of the supporting member is deviated from the center of the scanning signal wiring in the direction away from the electron-emitting device connected to the scanning signal wiring in which the supporting member is arranged. an image forming apparatus.

That is, according to the present invention, the scanning signal wiring for applying the selection voltage (driving voltage) and the non-selection voltage (non-driving voltage) smaller than the selection voltage to the electron-emitting device is described above. Electrons emitted from the electron-emitting devices are supported by the structure in which the center of the supporting member is displaced from the center of the scanning-signal wiring in the direction away from the electron-emitting device connected to the scanning-signal wiring in which the supporting member is arranged. It is possible to prevent the member (spacer) from being blocked and solve the problem that the brightness of the phosphor near the support member is reduced.

In addition to the above structure, when the support member is a conductive support member, when the conductive support member (conductive spacer) is arranged on the scanning signal wiring, the surface of the conductive support member is charged. The generated electrons are more preferable because they are discharged to the scanning signal wiring.

Further, in addition to the above structure, the electron-emitting device
Is located at the center between the adjacent scan signal wirings.
And, wherein the amount of the central shifting heart or <br/> et al in said scanning signal line of the support member δ is to satisfy the following relation preferably.

(Ef) / 2 ≧ δ ≧ (c + b / 2) −
{(A−f) / 2} c = 2Kd√ {Vf / (Va−Vf)}, e> f, a>
f, a> e, Va> Vf a: distance between the centers of the scanning signal wirings b: spot diameter of the electron beam c: deviation amount of the electron beam trajectory d: distance e between the substrate and the face plate : Width of the scanning signal wiring f: thickness of the supporting member Vf: device voltage Va applied to the electron-emitting device: acceleration voltage K applied to the acceleration electrode K: proportional constant

Δ ≧ (c + b / 2)-{(af) /
2} By adopting the configuration, it is possible to solve the problem that the electrons emitted from the electron-emitting device collide with the surface of the supporting member (spacer) and are blocked, and the brightness of the phosphor near the supporting member is reduced. You can

Further, by adopting the above-mentioned (ef) / 2 ≧ δ structure, the fixing strength between the supporting member and the scanning signal wiring is lowered without the supporting member (spacer) protruding from the scanning signal wiring. Can be prevented.

[0037] (2) Further, the present invention, each plurality of electron-emitting devices are wired in, for applying a non-selection voltage voltage is greater than the selected voltage and the said selected voltage to the plurality of electron-emitting devices The plurality of scanning signal wirings are
The emitting element is located on the same side with respect to each scanning signal wiring.
Are arranged on the substrate, and are arranged for the plurality of scanning signals.
The line spacing is the same and connected to each scan signal wiring.
An electron source having the same distance between the lined electron-emitting devices, a face plate arranged facing the substrate and having an accelerating electrode for accelerating an electron beam, the substrate and the face plate. In an image forming apparatus having a supporting member disposed between and on the scanning signal wiring, in a direction away from an electron-emitting device which is adjacent to the scanning signal wiring in which the supporting member is disposed and is not connected. The image forming apparatus is characterized in that the center of the supporting member is displaced from the center of the scanning signal wiring.

That is, according to the present invention, the scanning signal wiring for applying the selection voltage (driving voltage) and the non-selection voltage (non-driving voltage) higher than the selection voltage to the electron-emitting device is described above. Emission from the electron-emitting device is achieved by adopting a configuration in which the center of the support member is displaced from the center of the scanning-signal wiring in the direction adjacent to the scanning-signal wiring in which the supporting member is arranged and away from the unconnected electron-emitting device It is possible to prevent the generated electrons from being blocked by the support member (spacer) and solve the problem that the brightness of the phosphor near the support member decreases.

In addition to the above structure, when the support member is a conductive support member, when the conductive support member (conductive spacer) is arranged on the scanning signal wiring, the surface of the conductive support member is charged. The generated electrons are more preferable because they are discharged to the scanning signal wiring.

Further, in addition to the above constitution, the electron-emitting device
Is located at the center between the adjacent scan signal wirings.
And, it is preferable that the amount of shifting the center of the support member from the center of the scan signal wiring δ satisfy the following relationship.

(E−f) / 2 ≧ δ ≧ (c + b / 2) −
{(A−f) / 2} c = 2Kd√ {Vf / (Va−Vf)}, e> f, a>
f, a> e, Va> Vf a: distance between the centers of the scanning signal wirings b: spot diameter of the electron beam c: deviation amount of the electron beam trajectory d: distance e between the substrate and the face plate : Width of the scanning signal wiring f: thickness of the supporting member Vf: device voltage Va applied to the electron-emitting device: acceleration voltage K applied to the acceleration electrode K: proportional constant

Δ ≧ (c + b / 2)-{(a-f) /
2} By adopting the configuration, it is possible to solve the problem that the electrons emitted from the electron-emitting device collide with the surface of the supporting member (spacer) and are blocked, and the brightness of the phosphor near the supporting member is reduced. You can

Further, by adopting the above-mentioned (ef) / 2 ≧ δ configuration, the fixing strength between the supporting member and the scanning signal wiring is lowered without the supporting member (spacer) protruding from the scanning signal wiring. Can be prevented.

Here, the principle of the present invention will be described with reference to FIG. FIG. 9 is a cross-sectional view showing the basic structure of the image forming apparatus of the present invention and corresponds to the AA ′ cross section of FIG. 1
Reference numeral 1 is a substrate, 15 is a rear plate, 16 is a side wall, and 17 is a face plate, and an envelope is formed by combining 15, 16, and 17. 20 is a spacer, 0 of 13
Is a scanning signal wiring on which a spacer is placed, and 18 is a phosphor.
Reference numeral 9 is a conductive member (metal back), 1 is a scanning signal wiring connected to a driven element, and 2 is a scanning signal wiring connected to a non-driving element. Reference numerals 111-1 and 111-2 are elements formed on the substrate 11.
The electron beam 112 1 is emitted from 1 of 11 and the phosphor 1
Image on 8. Va is the anode voltage, and Vf 'is a voltage for preventing the voltage applied to the non-driven element from exceeding the electron emission threshold voltage Vth as shown in FIG. In order to drive 2 of the element 111 and emit 2 of the electron beam 112, 1 of the scanning signal wiring 13 is shifted to the right side in the drawing, and 2 of the scanning signal wiring 13 other than that. (Not shown).

At this time, the spacer 20 is positioned so as to deviate from the center of 0 of the scanning signal wiring 13 in the direction in which 1 of the electron beam 112 and 2 of 112 are tilted, and the 0 of the scanning signal wiring 13 is always required. To contact. As a result, 1 of the electron beam 112 reliably reaches the phosphor 18 without colliding with the spacer 20. Further, although the spacer approaches the element 111 located on the side where the spacer is displaced, the electron beam 112 of the electron beam 112 is emitted in the direction away from the spacer by the driving method.
It reaches the phosphor without colliding with the spacer. Further, the electron beam emitted from the element not adjacent to the spacer also inclines similarly, but reaches the phosphor without any hindrance.

The image forming apparatus of the present invention may have the following forms. The cold cathode device is a cold cathode device having a conductive film including an electron emitting portion between a pair of electrodes, and particularly preferably a surface conduction type emission device. The electron source is an electron source in a simple matrix arrangement having a plurality of cold cathode elements arranged in a matrix by a plurality of row-direction wirings and a plurality of column-direction wirings. The electron source has a plurality of rows of cold cathode elements in which a plurality of cold cathode elements arranged in parallel are connected at both ends (referred to as row direction), and is arranged in a direction orthogonal to this wiring (referred to as column direction). Along the cold cathode element, a control electrode (also referred to as a grid) arranged above the cold cathode element forms a ladder-shaped electron source that controls electrons from the cold cathode element. Further, according to the idea of the present invention, it is not limited to the image forming apparatus suitable for display, but as an alternative light emitting source such as a light emitting diode of an optical printer including a photosensitive drum and a light emitting diode, the above-mentioned An image forming apparatus can also be used. At this time, by appropriately selecting the above-mentioned m row-direction wirings and n column-direction wirings, it can be applied not only as a line-shaped light emitting source but also as a two-dimensional light-emitting source. In this case, the image forming member is not limited to a substance that directly emits light such as a phosphor used in the following examples.
It is also possible to use a member on which a latent image is formed by charging with electrons.

[0047]

DETAILED DESCRIPTION OF THE INVENTION

(1) Outline of Conductive Spacer The present invention is a planar type image forming apparatus using an antistatic film as a spacer. As shown in the schematic structure of FIG. 6 (details will be described later), a plurality of cold cathode elements 1012 are provided. Formed substrate 1
011 and a transparent face plate 1017 on which a fluorescent film 1018 as a light emitting material is formed face each other via a spacer 1020, and the spacer 1020 has a specific resistance of 0.1 to 10 on the surface of an insulating member. 8th power Ωc
The image forming apparatus is characterized in that aluminum of m, a transition metal alloy nitrogen compound film, and a metal oxide film are coated. Alternatively, the spacer 1020 is formed of aluminum having a specific resistance of 0.1 to 10 8 Ωcm on the surface of the insulating member, a transition metal alloy nitrogen compound film, a metal oxide film, and the oxidation of the aluminum transition metal alloy formed at the boundary thereof. The image forming apparatus is characterized by being coated with a material or a nitride film.

In the image forming apparatus of the present invention, one side of the spacer 1020 has a substrate 1 on which cold cathode elements are formed.
It is electrically connected to the wiring on 011. The opposite sides are electrically connected to an accelerating electrode (metal back 1019) for causing electrons emitted from the cold cathode device to collide with the light emitting material (fluorescent film 1018) with high energy.
That is, a current obtained by dividing the acceleration voltage by the resistance value of the antistatic film is passed through the antistatic film formed on the surface of the spacer. Therefore, the resistance value Rs of the spacer is set to a desired range from the viewpoint of antistatic and power consumption. From the viewpoint of antistatic, the surface resistance R □ is preferably 10 12 Ω or less. 11 of 10 to obtain sufficient antistatic effect
It is more preferable that the power is less than or equal to Ω. The lower limit of the surface resistance depends on the shape of the spacer and the voltage applied between the spacers, but it is preferably 10 5 Ω or more.

Thickness of antistatic film formed on insulating material
The t is preferably in the range of 10 nm to 1 μm. Although it depends on the surface energy of the material, the adhesion to the substrate, and the substrate temperature, a thin film of 10 nm or less is generally formed in an island shape, and the resistance is unstable and the reproducibility is poor. On the other hand, when the film thickness t is 1 μm or more, the film stress increases, the risk of film peeling increases, and the film forming time becomes long, resulting in poor productivity. Therefore, the film thickness is 50
It is desirable to be ~ 500 nm. The surface resistance R □ is ρ / t, and from the preferable range of R □ and t described above, the specific resistance ρ of the antistatic film is preferably 0.1 to 10 8 Ωcm. Further, in order to realize the more preferable range of the surface resistance and the film thickness, it is preferable that ρ be 10 2 to 10 6 Ωcm. As described above, the temperature of the spacer rises when a current flows through the antistatic film formed on the spacer or when the entire display generates heat during operation. If the resistance temperature coefficient of the antistatic film has a large negative value, the resistance value decreases when the temperature rises, the current flowing through the spacer increases, and the temperature rises further. And the current continues to increase until it exceeds the limit of the power supply. The value of the temperature coefficient of resistance at which such a current runaway occurs is empirically negative and the absolute value is 1% or more. That is, the resistance temperature coefficient of the antistatic film is preferably less than -1%.

Metal oxides are excellent as materials having antistatic film properties. Among the metal oxides, oxides of chromium, nickel and copper are preferable materials. The reason is considered that these oxides have a relatively low secondary electron emission efficiency and are difficult to be charged even when the electrons emitted from the electron-emitting device hit the spacer. In addition to metal oxides, 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. However, it is difficult to adjust the resistance value of the above metal oxide or carbon to the range of the specific resistance desired as the antistatic film, or the resistance is likely to change depending on the atmosphere. poor. The nitride of aluminum and a transition metal alloy can control the resistance value in a wide range from a good conductor to an insulator by adjusting the composition of the transition metal. Furthermore, it is a stable material with little change in resistance value in the process of manufacturing a display device described later. And,
The temperature coefficient of resistance is less than -1%, and it is a material that is practically easy to use. Examples of transition metal elements include Ti, Cr and Ta.

(2) Outline of Image Display Device Next, the configuration and manufacturing method of the display panel of the image display device to which the present invention is applied will be described with reference to specific examples.

FIG. 6 is a perspective view of the display panel used in the embodiment, in which a part of the panel is cut away to show the internal structure.

In the figure, 1015 is a rear plate, and 1016.
Is a side wall, 1017 is a face plate, and 1015
1017 to 1017 form an airtight container for maintaining a vacuum inside the display panel. When assembling an airtight container, it is necessary to seal the joints of each member in order to maintain sufficient strength and airtightness.For example, frit glass is applied to the joints, and the joints are placed in the atmosphere or nitrogen atmosphere. Sealing was achieved by firing at 400-500 degrees for 10 minutes or more. A method of evacuating the inside of the airtight container will be described later. The inside of the airtight container is 1
Since a vacuum of about 0 to the 6th power [Torr] is maintained, the spacer 10 is used as an atmospheric pressure resistant structure for the purpose of preventing destruction of the airtight container due to atmospheric pressure or an unexpected impact.
20 are provided.

A substrate 1011 is provided on the rear plate 1015.
, But the cold cathode element 1012 is fixed on the substrate.
Are formed by N × M. (N and M are positive integers of 2 or more and are appropriately set in accordance with the target number of display pixels. For example, in a display device intended to display a high-definition television, N = 3000, M = 1000 or more is desirable.) The N × M cold cathode elements are simple matrix wiring by M row-direction wirings 1013 and N column-direction wirings 1014. The portion composed of 1011-1014 is called a multi-electron beam source.

The multi-electron beam source used in the image display device of the present invention is not limited in the material, shape or manufacturing method of the cold cathode element as long as it is an electron source in which cold cathode elements are wired in a simple matrix. Therefore, for example, a surface conduction electron-emitting device, an FE type, or a MIM type cold cathode device can be used.

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

FIG. 10 is a plan view of the multi-electron beam source used in the display panel of FIG. Board 1011
A surface conduction electron-emitting device similar to that shown in FIG.
Wiring is performed in a simple matrix by 13 and column direction wiring electrodes 1014. An insulating layer (not shown) is formed between the electrodes at the intersections of the row-direction wiring electrodes 1013 and the column-direction wiring electrodes 1014 to maintain electrical insulation.

A cross section taken along the line BB 'of FIG. 10 is shown in FIG.
Shown in.

The multi-electron source having such a structure is
After forming the row-direction wiring electrodes 1013, the column-direction wiring electrodes 1014, the interelectrode insulating layer (not shown), and the device electrodes of the surface conduction electron-emitting device and the conductive thin film on the substrate in advance,
Row-direction wiring electrode 1013 and column-direction wiring electrode 1014
It was manufactured by supplying power to each element through the device and performing energization forming process (described later) and energization activation process (described later).

In this embodiment, the substrate 1011 of the multi-electron beam source is fixed to the rear plate 1015 of the airtight container. However, the substrate 101 of the multi-electron beam source is fixed.
1 has a sufficient strength, the substrate 101 of the multi-electron beam source is used as the rear plate of the airtight container.
You may use 1 itself.

A fluorescent film 1018 is formed on the lower surface of the face plate 1017. Since the present embodiment is a color display device, a CR film is provided on the fluorescent film 1018.
Phosphors of three primary colors of red, green, and blue used in the field of T are separately coated. The phosphors of each color are shown in FIG.
As shown in (a) of FIG. 5, the conductors 1010 are painted in stripes, and black conductors 1010 are provided between the phosphor stripes. The purpose of providing the black conductor 1010 is to prevent the display color from being shifted even if the irradiation position of the electron beam is slightly shifted, and to prevent the reflection of external light so that the display contrast is lowered. To prevent the fluorescent film from being charged up by the electron beam. Although graphite was used as a main component for the black conductor 1010, other materials may be used as long as they are suitable for the above purpose.

The method of separately coating the phosphors of the three primary colors is not limited to the stripe-shaped arrangement shown in FIG. 12 (a), and for example, the delta arrangement shown in FIG. 12 (b), Other arrangements may be used.

In this embodiment, the fluorescent film 101 is used.
As shown in FIG. 13, 8 adopts a stripe shape in which each color phosphor 21a extends in the column direction (Y direction), and the black conductor 21b is used not only between each color phosphor (R, G, B) 21a. , A fluorescent film arranged so as to separate each pixel in the Y direction is used, and the spacer 1020 is a black conductor 21b region (line width 300 [micrometer]) parallel to the row direction (X direction). It was placed inside via a metal back 1019. In addition, when performing the above-mentioned sealing, it is necessary to associate each color phosphor 21a with each element arranged on the substrate 1011. Therefore, the rear plate 1015, the face plate 1017, and the spacer 1020 have sufficient positions. I made a match.

In the case of producing a monochrome display panel, a monochromatic phosphor material may be used for the phosphor film 1018, and a black conductive material is not necessarily used.

On the rear plate side surface of the fluorescent film 1018, a metal back 1019 known in the field of CRT is used.
Is provided. The purpose of providing the metal back 1019 is
A part of the light emitted by the fluorescent film 1018 is specularly reflected to improve the light utilization rate, and the fluorescent film 101 is prevented from colliding with negative ions.
8 is to be protected, to act as an electrode for applying an electron beam accelerating voltage, and to act as a conductive path for excited electrons in the fluorescent film 1018. The metal back 1019 was formed by forming a fluorescent film 1018 on the face plate substrate 1017, smoothing the surface of the fluorescent film, and vacuum-depositing Al on the surface.
The metal back 1019 is not used when the fluorescent material for the low voltage is used for the fluorescent film 1018.

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

FIG. 14 is a schematic cross-sectional view taken along the line AA 'in FIG. 6, and the numbers of the respective parts correspond to those in FIG. Spacer 102
0 forms a high resistance film 1020 b for the purpose of preventing electrification on the surface a of the insulating member 1020, and the inside of the face plate 1017 (metal back 1019 etc.) and the surface of the substrate 1011 (row-direction wiring 1013). Alternatively, the low resistance film 10 is formed on the contact surface of the spacer facing the column-directional wiring 1014).
20c is a member formed by forming a film, and is arranged by the necessary number and a necessary interval for achieving the above-mentioned object, and is fixed to the inside of the face plate and the surface of the substrate 1011 by the bonding material 1041. . In addition, the high resistance film 1
B of 020 among the surfaces of a of the insulating member 1020,
A low resistance film 1020c formed on at least the spacer 1020 is formed on at least the surface of the airtight container exposed in vacuum.
And the face plate 10 via the bonding material 1041.
Inside 17 (metal back 1019, etc.) and substrate 101
1 surface (row direction wiring 1013 or column direction wiring 101
4) electrically connected to. In the embodiment described here, 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.

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 1013 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. This point has already been described.

Examples of the a of the insulating member 1020 of the spacer 1020 include quartz glass, glass having a reduced content of impurities such as Na, soda lime glass, and ceramic members such as alumina. The insulating member 10
20 a has a thermal expansion coefficient of the airtight container and the substrate 1011.
A member close to the member forming is preferable.

Further, as the high resistance film 1020b, the surface resistance value is from 10 5 [Ω / □] to 10 10 in consideration of the maintenance of the antistatic effect and the suppression of the power consumption due to the leakage current as described above. It is preferably in the range of the 12th power [Ω / □], and the above-mentioned various materials are used as the material.

The low resistance film 1020c is the high resistance film 1
It is sufficient to select a resistance value that is sufficiently lower than 2 of 020,
It is composed of metals such as Ni, Cr, Au, Mo, W, Ti, Al, Cu, Pd, or alloys, and metals such as Pd, Ag, Au, RuO2, Pd-Ag, metal oxides, and glass. Printed conductor or In
It is appropriately selected from a transparent conductor such as 2O3-SnO2 and a semiconductor material such as polysilicon.

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.

Dx1 to Dxm and Dy1 to Dyn and Hv are terminals for electrical connection having an airtight structure provided for electrically connecting the display panel and an electric circuit (not shown). Dx1 to Dxm are row wirings 10 of the multi-electron beam source
13, Dy1 to Dyn are column direction wirings 1014 of a multi-electron beam source, and Hv is a metal back 1 of a face plate.
It is electrically connected to 019.

To evacuate the inside of the airtight container to a vacuum, after assembling the airtight container, an exhaust pipe (not shown) and a vacuum pump are connected, and the inside of the airtight container is reduced to the power of 10 minus 7 [T].
orr]. After that, the exhaust pipe is sealed, but in order to maintain the degree of vacuum 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 deposition.
Due to the adsorption action of the getter film, the inside of the airtight container is maintained at a vacuum degree of 1 × 10 −5 to 1 × 10 −7 [Torr].

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 Dx1 to Dxm and Dy1 to Dyn outside the container, 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 emitted electrons to collide with the inner surface of the face plate 1017. As a result, the phosphors of each color forming the phosphor film 1018 are excited and emit light, and an image is displayed.

Generally, the voltage applied to 1012 of the surface conduction electron-emitting device of the present invention, which is a cold cathode device, is 12 to 16.
[V] degree, metal back 1019 and cold cathode device 101
2 is about 0.1 [mm] to 8 [mm], and the voltage between the metal back 1019 and the cold cathode device 1012 is 0.
It is about 1 [kV] to 10 [kV].

The basic configuration and manufacturing method of the display panel and the outline of the image display device according to the embodiments of the present invention have been described above.

(3) Method for manufacturing multi-electron beam source Next, the multi-electron beam used for the display panel of the above-mentioned embodiment is used.
The method of manufacturing the aluminum source will be described. The multi-electron beam source used in the image display device of the present invention is not limited in the material, shape or manufacturing method of the cold cathode element as long as it is an electron source in which cold cathode elements are wired in a simple matrix. Therefore, for example, a surface conduction electron-emitting device, an FE type, or a MIM type cold cathode device can be used.

However, under the circumstances where a display device having a large display screen and being inexpensive is required, the surface conduction electron-emitting device is particularly preferable among these cold cathode devices. That is, in the FE type, since the relative position and shape of the emitter cone and the gate electrode greatly affect the electron emission characteristics, an extremely high precision manufacturing technique is required, but this requires a large area and a reduction in manufacturing cost. Will be a disadvantageous factor in achieving. Further, in the MIM type, it is necessary to make the insulating layer and the upper electrode thin and uniform, which is also a disadvantageous factor in achieving a large area and a reduction in manufacturing cost. In this respect, the surface conduction electron-emitting device has a relatively simple manufacturing method, so that it is easy to increase the area and reduce the manufacturing cost. Further, the inventors have found that among the surface conduction electron-emitting devices, those in which the electron-emitting portion or its peripheral portion is formed of a fine particle film have particularly excellent electron-emitting characteristics and can be easily manufactured. Therefore, it can be said that it is most suitable for use in a multi-electron beam source of a high-luminance and large-screen image display device. Therefore, in the display panel of the above embodiment, the surface conduction electron-emitting device in which the electron emitting portion or its peripheral portion is formed of the fine particle film is used. Therefore, the basic configuration, manufacturing method, and characteristics of a suitable surface conduction electron-emitting device will be described first, and then the structure of a multi-electron beam source in which a large number of devices are wired in a simple matrix will be described.

(Preferable Element Configuration and Manufacturing Method of Surface Conduction Type Emitting Element) Typical configurations of the surface conduction type emitting element in which the electron emitting portion or its peripheral portion is formed of a fine particle film include a planar type and a vertical type There are different types.

(Plane Type Surface Conduction Type Emitting Element) First, the element structure and manufacturing method of the plane type surface conduction type emitting element will be described. FIG. 11 is a plan view (a) and a cross-sectional view (b) for explaining the configuration of the flat surface conduction electron-emitting device. In the figure, 1101 is a substrate, 1102 and 1103 are element electrodes, 1104 is a conductive thin film, 1105.
Is an electron emission portion formed by energization forming processing, 1
Reference numeral 113 is a thin film formed by the energization activation process.

As the substrate 1101, for example, various glass substrates such as quartz glass and soda lime glass, various ceramic substrates such as alumina, or an insulating layer made of, for example, SiO 2 is laminated on the above various substrates. Substrate, etc. can be used.

Further, the device electrodes 1102 and 1103 provided on the substrate 1101 so as to face each other in parallel to the substrate surface are made of a conductive material. For example, N
i, Cr, Au, Mo, W, Pt, Ti, Cu, Pd,
Materials such as Ag and the like, alloys of these metals, metal oxides such as In2 O3 -SnO2, semiconductors such as polysilicon, and the like may be appropriately selected and used. The electrodes can be easily formed by using a film forming technique such as vacuum deposition and a patterning technique such as photolithography and etching, but other methods (for example, printing technique) can be used to form the electrodes. It doesn't matter if it is formed.

The shapes of the device electrodes 1102 and 1103 are appropriately designed according to the application purpose of the electron-emitting device.
Generally, the electrode spacing L is designed by selecting an appropriate value from the range of several hundred angstroms to several hundreds of micrometer, but it is preferable that the electrode spacing L is applied to a display device. The range is from a micrometer to several tens of micrometers. Further, regarding the thickness d of the device electrode,
Usually, an appropriate value is selected from the range of several hundred angstroms to several micrometers.

A fine particle film is used for the conductive thin film 1104. The fine particle film described here is a film containing a large number of fine particles as constituent elements (including an island-shaped aggregate).
Refers to. A microscopic examination of the particulate film usually reveals that
A structure in which individual fine particles are arranged apart from each other, a structure in which fine particles are adjacent to each other, or a structure in which fine particles overlap each other are observed.

The particle diameter of the fine particles used for the fine particle film is in the range of several angstroms to several thousand angstroms, but the preferable range is 10 angstroms to 200 angstroms. belongs to. Further, the film thickness of the fine particle film is appropriately set in consideration of various conditions as described below. That is, the device electrode 11
02 or 1103, necessary conditions for good electrical connection, necessary conditions for conducting the energization forming described below, and necessary electric resistance of the fine particle film itself to be an appropriate value described below. Conditions, etc. In particular,
It is set within the range of several angstroms to several thousand angstroms, but the range of 10 angstroms to 500 angstroms is particularly preferable.

Materials that can be used to form the fine particle film include, for example, Pd, Pt, Ru, Ag,
Au, Ti, In, Cu, Cr, Fe, Zn, Sn, T
Metals such as a, W, Pb, etc., PdO, S
Oxides such as nO2, In2 O3, PbO, Sb2 O3, HfB2, ZrB2, LaB6, C
borides such as eB6, YB4, GdB4, etc., TiC, ZrC, HfC, TaC, SiC, WC,
Carbides such as TiN, ZrN, Hf
Nitride and other such nitrides, Si, Ge and other such semiconductors, carbon, and the like can be mentioned, and these are appropriately selected.

As described above, the conductive thin film 1104 is formed of a fine particle film. Regarding the sheet resistance value,
It was set so as to fall within the range of 10 3 to 10 7 [ohm / sq].

The conductive thin film 1104 and the device electrode 11
Since 02 and 1103 are preferably electrically connected well, they have a structure in which some of them overlap each other. In the example of FIG. 11, the overlapping manner is
The substrate, the device electrode, and the conductive thin film are stacked in this order from the bottom, but in some cases, the substrate, the conductive thin film, and the device electrode may be stacked in this order from the bottom.

Further, the electron emitting portion 1105 is a crack-like portion formed in a part of the conductive thin film 1104, and has an electrically higher resistance than the surrounding conductive thin film. The crack is formed by subjecting the conductive thin film 1104 to a later-described energization forming process. Fine particles having a particle diameter of several angstroms to several hundred angstroms may be arranged in the cracks. Since it is difficult to accurately and accurately show the actual position and shape of the electron emitting portion, the electron emitting portion is schematically shown in FIG.

The thin film 1113 is a thin film made of carbon or a carbon compound, and covers the electron emitting portion 1105 and its vicinity. The thin film 1113 is formed by performing an energization activation process described later after the energization forming process.

The thin film 1113 is made of single crystal graphite, polycrystalline graphite, amorphous carbon, or a mixture thereof, and the film thickness is 500 [angstrom] or less, but 300 [angstrom]. -Mu] It is more preferable that The actual thin film 1113
Since it is difficult to precisely illustrate the position and shape of
In the figure, it is shown schematically. Further, in the plan view (a), an element in which a part of the thin film 1113 is removed is shown.

The basic structure of a preferable element has been described above, but the following elements were used in the examples.

That is, soda lime glass was used for the substrate 1101, and Ni thin films were used for the device electrodes 1102 and 1103. The thickness d of the device electrode is 1000 [angstrom
], And the electrode interval L is 2 [micrometer].

Pd or P as the main material of the fine particle film
The thickness of the fine particle film was about 100 [angstrom] and the width W was 100 [micrometer] using dO.

Next, a method for manufacturing a suitable flat surface conduction electron-emitting device will be described.

FIGS. 15A to 15D are sectional views for explaining the manufacturing process of the surface conduction electron-emitting device, and the notation of each member is the same as that in FIG.

1) First, as shown in FIG. 15A, device electrodes 1102 and 1103 are formed on a substrate 1101.

Before forming, the substrate 1
101 is thoroughly washed with a detergent, pure water, and an organic solvent,
The material of the device electrode is deposited. (As a method of depositing, for example, a vacuum film forming technique such as a vapor deposition method or a sputtering method may be used.) After that, the deposited electrode material is patterned using a photolithography-etching technique, and ( a) a pair of device electrodes (1102 and 110)
3) is formed.

2) Next, a conductive thin film 1104 is formed as shown in FIG.

In forming the film, first, an organic metal solution is applied to the substrate of the above (a), dried, heated and baked to form a fine particle film, and then patterned into a predetermined shape by photolithography / etching. -Train. here,
The organometallic solution is a solution of an organometallic compound whose main element is the material of the fine particles used for the conductive thin film. (Specifically, Pd was used as the main element in this example. Further, although the dipping method was used as the coating method in the examples, other methods such as a spinner method or a spray method may be used. .)

As a method for forming a conductive thin film made of a fine particle film, a method other than the method of applying an organometallic solution used in this embodiment, such as a vacuum evaporation method or a sputtering method,
Alternatively, a chemical vapor deposition method or the like may be used.

3) Next, as shown in FIG. 10C, the forming power supply 1110 to the device electrodes 1102 and 110 are connected.
An appropriate voltage is applied between 3 and the energization forming process is performed to form the electron emitting portion 1105.

The energization forming process is a structure suitable for energizing the electroconductive thin film 1104 made of a fine particle film to appropriately destroy, deform or alter a part of the electroconductive thin film 1104 to emit electrons. It is the process of changing to. A portion of the conductive thin film made of the fine particle film, which has been changed to a structure suitable for emitting electrons (that is, the electron emitting portion 110).
In 5), an appropriate crack is formed in the thin film.
Note that the electric resistance measured between the element electrodes 1102 and 1103 after the formation is significantly increased as compared with before the formation of the electron emission portion 1105.

In order to explain the energization method in more detail, FIG. 16 shows an example of an appropriate voltage waveform applied from the forming power supply 1110. When forming a conductive thin film made of a fine particle film, a pulsed voltage is preferable, and in the case of the present embodiment, a triangular wave pulse having a pulse width T1 at a pulse interval T2 as shown in FIG. It was applied continuously. At that time, the peak value Vpf of the triangular wave pulse was sequentially increased. Further, monitor pulses Pm for monitoring the formation state of the electron emission portion 1105 are inserted between the triangular wave pulses at appropriate intervals, and the current flowing at that time is measured by the ammeter 1.
Measured at 111.

In the embodiment, the pulse width T1 is 1 [milliseconds] and the pulse interval T2 is 1 in a vacuum atmosphere of about 10 <-5> [torr].
0 [millisecond], and the peak value Vpf is set to 0 for each pulse.
The voltage was increased by 1 [V]. Then, the monitor pulse Pm was inserted once every five pulses of the triangular wave were applied. The voltage Vpm of the monitor pulse is set to 0.1 [V] so that the forming process is not adversely affected. Then, at the stage where the electric resistance between the element electrodes 1102 and 1103 reaches 1 × 10 6 [ohm], that is, when the monitor pulse is applied, the current measured by the ammeter 1111 is 1 × 10 −7 [ohm]. A] When the following conditions were reached, the energization involved in the forming process was terminated.

The above method is a preferable method for the surface conduction electron-emitting device of this embodiment. For example, the design of the surface conduction electron-emitting device such as the material and thickness of the fine particle film or the element electrode spacing L is changed. In this case, it is desirable to appropriately change the energization conditions accordingly.

4) Next, as shown in FIG.
From the activation power source 1112 to the device electrodes 1102 and 1103
Appropriate voltage is applied between the two to perform energization activation treatment,
The electron emission characteristics are improved.

The energization activation process is a process of energizing the electron-emitting portion 1105 formed by the energization forming process under appropriate conditions to deposit carbon or a carbon compound in the vicinity thereof. (In the figure, a deposit made of carbon or a carbon compound is schematically shown as the member 1113.) Note that by performing the energization activation treatment, the emission current at the same applied voltage is typically compared to that before the activation. Specifically, it can be increased 100 times or more.

Specifically, 10 to the fourth power of 4 to 1
By periodically applying a voltage pulse in a vacuum atmosphere within a range of 0 to the fifth power [torr], carbon or a carbon compound originating from an organic compound existing in the vacuum atmosphere is deposited. The deposit 1113 is one of single crystal graphite, polycrystalline graphite, amorphous carbon, or a mixture thereof, and has a film thickness of 500.
[Angstrom] or less, more preferably 300 [Angstrom] or less.

In order to describe the energization method in more detail, FIG. 22A shows an example of an appropriate voltage waveform applied from the activation power supply 1112. In the present embodiment, the energization activation process is performed by periodically applying a rectangular wave of a constant voltage. Specifically, the rectangular wave voltage Vac is 14 [V],
The pulse width T3 is 1 [millisecond] and the pulse interval T4 is 10
[Millisecond]. The above-mentioned energization conditions are preferable conditions for the surface conduction electron-emitting device of this embodiment, and when the design of the surface conduction electron emission device is changed, it is desirable to appropriately change the conditions accordingly.

Reference numeral 1114 shown in FIG. 11 (d) is an anode electrode for capturing the emission current Ie emitted from the surface conduction electron-emitting device, to which a DC high voltage power supply 1115 and an ammeter 1116 are connected. There is. (Note that the substrate 1101
When the activation treatment is carried out after being incorporated into the display panel, the fluorescent surface of the display panel is connected to the anode electrode 1114.
Used as. While the voltage is applied from the activation power supply 1112, the emission current Ie is measured by the ammeter 1116 to monitor the progress of the energization activation process, and the activation power supply 11 is activated.
12 operations are controlled. An example of the emission current Ie measured by the ammeter 1116 is shown in FIG. 22 (b). When the pulse voltage is started to be applied from the activation power supply 1112, the emission current Ie increases with the passage of time, but the emission current Ie saturates. Will almost never increase. As described above, when the emission current Ie is almost saturated, the voltage application from the activation power supply 1112 is stopped, and the energization activation process is ended.

The above energization conditions are preferable conditions for the surface-conduction type electron-emitting device of this embodiment, and when the design of the surface-conduction type electron-emitting device is changed, the conditions should be changed accordingly. desirable.

As described above, the plane type surface conduction electron-emitting device shown in FIG. 15 (e) was manufactured.

(Vertical Surface-Conduction Emission Element) Next, another typical structure of the surface-conduction emission element in which the electron emission portion or its periphery is formed of a fine particle film, that is, vertical surface conduction emission The configuration of the element will be described.

FIG. 17 is a schematic cross-sectional view for explaining the basic structure of the vertical type, in which 1201 is a substrate.
202 and 1203 are element electrodes, 1206 is a step forming member, 1204 is a conductive thin film using a fine particle film, 1205
Is an electron emission portion formed by energization forming processing, 1
213 is a thin film formed by the energization activation process.

The vertical type is different from the above-described flat type in that one of the element electrodes (1202) is provided on the step forming member 1206, and the conductive thin film 1204 covers the side surface of the step forming member 1206. The point is that they are covered. Therefore, the device electrode interval L in the flat type of FIG. 102 is set as the step height Ls of the step forming member 1206 in the vertical type. For the substrate 1201, the device electrodes 1202 and 1203, and the conductive thin film 1204 using a fine particle film, it is possible to use the materials listed in the description of the planar type similarly. For the step forming member 1206, an electrically insulating material such as SiO2 is used.

Next, a method of manufacturing a vertical type surface conduction electron-emitting device will be described. 18A to 18F are cross-sectional views for explaining the manufacturing process, and the notation of each member is the same as in FIG.
Same as 7.

1) First, as shown in FIG. 18A, a device electrode 1203 is formed on a substrate 1201.

2) Next, as shown in FIG. 11B, an insulating layer for forming the step forming member is laminated. The insulating layer may be formed by laminating, for example, SiO2 by a sputtering method, but other film forming methods such as a vacuum deposition method and a printing method may be used.

3) Next, as shown in FIG. 10C, the device electrode 1202 is formed on the insulating layer.

4) Next, as shown in FIG. 9D, a part of the insulating layer is removed by using, for example, an etching method to expose the device electrode 1203.

5) Next, as shown in FIG. 7E, a conductive thin film 1204 using a fine particle film is formed. For formation, a film forming technique such as a coating method may be used as in the case of the flat type.

6) Next, as in the case of the planar type, energization forming processing is performed to form an electron emitting portion.
(The same process as the planar energization forming process described with reference to FIG. 15C may be performed.)

7) Next, as in the case of the planar type, an energization activation process is performed to deposit carbon or a carbon compound in the vicinity of the electron emitting portion. (The same process as the planar energization activation process described with reference to FIG. 15D may be performed.)

As described above, the vertical type surface conduction electron-emitting device shown in FIG. 18F was manufactured.

(Characteristics of Surface Conduction Type Emitting Element Used in Display Device) The element structure and manufacturing method of the plane type and vertical type surface conduction type emitting element have been described above. I will describe.

FIG. 8 shows typical examples of the (emission current Ie) vs. (device applied voltage Vf) characteristic and the (device current If) vs. (device applied voltage Vf) characteristic of the device used in the display device. . The emission current Ie is significantly smaller than the device current If, and it is difficult to show them on the same scale. In addition, these characteristics are changed by changing design parameters such as the size and shape of the device. Therefore, the two graphs are shown in arbitrary units.

The element used in the display device has the following three characteristics regarding the emission current Ie.

First, a certain voltage (this is the threshold voltage Vth
The emission current Ie sharply increases when a voltage of the above magnitude is applied to the element, while the emission current Ie is hardly detected at a voltage lower than the threshold voltage Vth.

That is, it is a non-linear element having a clear threshold voltage Vth with respect to the emission current Ie.

Secondly, since the emission current Ie changes depending on the voltage Vf applied to the element, the emission current Ie at the voltage Vf.
The size of e can be controlled.

Thirdly, since the response speed of the current Ie emitted from the element is fast with respect to the voltage Vf applied to the element, the charge amount of the electrons emitted from the element depends on the length of time for applying the voltage Vf. You can control.

Due to the above-mentioned characteristics, the surface conduction electron-emitting device could be preferably used in a display device. For example, in a display device provided with a large number of elements corresponding to the pixels of the display screen, by utilizing the first characteristic, it is possible to sequentially scan the display screen for display. That is,
A threshold voltage Vt is applied to the driven element according to the desired emission brightness.
A voltage of h or more is appropriately applied, and a voltage of less than the threshold voltage Vth is applied to the non-selected element. By sequentially switching the elements to be driven, it is possible to sequentially scan the display screen for display.

By utilizing the second characteristic or the third characteristic, it is possible to control the light emission brightness, and therefore it is possible to perform gradation display.

(4) Driving Circuit Configuration (and Driving Method) FIG. 19 is a block diagram showing a schematic configuration of a driving circuit for performing television display based on an NTSC television signal. In the figure, a display panel 1701 corresponds to the above-mentioned display panel, and is manufactured and operates as described above. The scanning circuit 1702 scans a display line, and the control circuit 1703 generates a signal or the like to be input to the scanning circuit. The shift register 1704 shifts the data for each line, and the line memory 1705 inputs the data for one line from the shift register 1704 to the modulation signal generator 1707. The sync signal separation circuit 1706 separates the sync signal from the NTSC signal. Hereinafter, the function of each part of the apparatus of FIG. 19 will be described in detail.

First, the display panel 1701 has terminals Dx1 to Dxm, terminals Dy1 to Dyn, and high-voltage terminal Hv.
Is connected to an external electric circuit via. this house,
To the terminals Dx1 to Dxm, multi-electron beam sources provided in the display panel 1701, that is, cold cathode elements arranged in a matrix of m rows and n columns in a matrix are sequentially driven row by row (n elements). Scanning signal is applied.
On the other hand, a modulation signal for controlling the output electron beam of each of the n elements for one row selected by the scanning signal is applied to the terminals Dy1 to Dyn. The high voltage terminal Hv is supplied with a DC voltage of, for example, 5 [kV] from the DC voltage source Va, which is sufficient to excite the phosphor into the electron beam output from the multi-electron beam source. It is an accelerating voltage for applying energy.

Next, the scanning circuit 1702 will be described. The circuit has m switching elements (in the figure,
S1 to Sm), each switching element selects either the output voltage of the DC voltage source Vx or 0 [V] (ground level) to display the display panel 1701. The terminals Dx1 to Dxm are electrically connected. Each of the switching elements S1 to Sm has a control signal Tsc output from the control circuit 1703.
It works based on an, but in reality, for example, FE
It can be easily configured by combining switching elements such as T. The DC voltage source V
x is set so as to output a constant voltage so that the drive voltage applied to the unscanned element is equal to or lower than the electron emission threshold voltage Vth voltage based on the characteristics of the electron emission element illustrated in FIG. .

The control circuit 1703 has a function of matching the operations of the respective parts so that an appropriate display is performed based on the image signal input from the outside. Based on the synchronization signal Tsync sent from the synchronization signal separation circuit 1706 described below, control signals Tscan, Tsft, and Tmry are generated for each unit. The sync signal separation circuit 1706 is a circuit for separating a sync signal component and a luminance signal component from an externally input NTSC system television signal, and as is well known, a frequency separation (filter) circuit is used. It can be easily configured. The sync signal separated by the sync signal separation circuit 1706 is composed of a vertical sync signal and a horizontal sync signal as is well known, but here, for convenience of explanation, it is shown as a Tsync signal. On the other hand, the luminance signal component of the image separated from the television signal is referred to as a DATA signal for convenience, but the signal is input to the shift register 1704.

The shift register 1704 is for serial / parallel conversion of the DATA signal serially input in time series for each line of the image, and is based on the control signal Tsft sent from the control circuit 1703. Works. That is, it can be said that the control signal Tsft is the shift clock of the shift register 1704. The serial / parallel converted image data for one line (corresponding to driving data for n electron-emitting devices) is output from the shift register 1704 as n signals Id1 to Idn.

The line memory 1705 is a storage device for storing data for one line of an image for a required time, and stores the contents of Id1 to Idn as appropriate according to the control signal Tmry sent from the control circuit 1703. The stored contents are output as I′d1 to I′dn and input to the modulation signal generator 1707.

The modulation signal generator 1707 is responsive to each of the image data I'd1 to I'dn to generate an electron emission element 10.
15 is a signal source for appropriately driving and modulating each of the output signals, and its output signal is supplied to the display panel 17 through terminals Dy1 to Dyn.
It is applied to the electron-emitting device 1015 in 01.

As described with reference to FIG. 8, the surface conduction electron-emitting device according to the present invention has the following basic characteristics with respect to the emission current Ie. That is, there is a clear threshold voltage Vth for electron emission (8 [V] in the surface conduction electron-emitting device of the embodiment described later), and electron emission occurs only when a voltage equal to or higher than the threshold Vth is applied. Also, the electron emission threshold Vt
For a voltage of h or higher, the emission current Ie also changes according to the voltage change as shown in the graph of FIG. From this,
When a pulsed voltage is applied to this device, for example, no electron emission occurs even if a voltage below the electron emission threshold Vth is applied, but when a voltage above the electron emission threshold Vth is applied, the surface conduction electron-emitting device is used. Emits an electron beam.
At that time, the intensity of the output electron beam can be controlled by changing the pulse peak value Vm. Further, it is possible to control the total amount of charges of the electron beam output by changing the pulse width Pw.

Therefore, as the method of modulating the electron-emitting device according to the input signal, the voltage modulation method, the pulse width modulation method or the like can be adopted. When carrying out the voltage modulation method, as the modulation signal generator 1707, a circuit of a voltage modulation method that generates a voltage pulse of a fixed length and appropriately modulates the peak value of the pulse according to the input data is used. be able to. When the pulse width modulation method is implemented, the modulation signal generator 1707 generates a voltage pulse having a constant crest value and appropriately modulates the width of the voltage pulse according to the input data. Any type of circuit can be used.

Shift register 1704 and line memory 1
705 may be a digital signal type or an analog signal type. That is, the serial of the image signal /
This is because parallel conversion and storage may be performed at a predetermined speed.

When the digital signal type is used, the output signal DATA of the sync signal separation circuit 1706 needs to be converted into a digital signal.
An A / D converter may be provided at the output section of 6. In connection with this, the circuit used for the modulation signal generator is slightly different depending on whether the output signal of the line memory 115 is a digital signal or an analog signal. That is, in the case of the voltage modulation method using a digital signal, for example, a D / A conversion circuit is used for the modulation signal generator 1707, and an amplification circuit or the like is added if necessary. In the case of the pulse width modulation method, the modulation signal generator 1707 includes, for example, a high-speed oscillator, a counter for counting the number of waves output from the oscillator, and a comparator for comparing the output value of the counter with the output value of the memory. A circuit that combines (comparators) is used. If necessary, an amplifier for voltage-amplifying the pulse-width-modulated modulation signal output from the comparator up to the driving voltage of the electron-emitting device can be added.

In the case of the voltage modulation method using an analog signal, the modulation signal generator 1707 can employ, for example, an amplifier circuit using an operational amplifier or the like, and a shift level circuit or the like can be added if necessary. In the case of the pulse width modulation method, for example, a voltage control type oscillation circuit (VCO)
Can be adopted, and an amplifier for amplifying the voltage up to the driving voltage of the electron-emitting device can be added if necessary.

In the image display device to which the present invention is applicable, which has the above-mentioned structure, the electron emission elements are electron-emitted by applying a voltage to the electron-emission elements through the terminals Dx1 to Dxm and Dy1 to Dyn. Occurs. Metal back 1019 or transparent electrode (not shown) via high-voltage terminal Hv
A high voltage is applied to the electron beam to accelerate the electron beam. The accelerated electrons collide with the fluorescent film 1018 and emit light to form an image.

The configuration of the image display apparatus described here is an example of the image forming apparatus to which the present invention can be applied, and various modifications can be made based on the idea of the present invention. Although the NTSC system has been mentioned as the input signal, the input signal is not limited to this, and the PAL, SECAM system, etc., and the TV signal (high-definition TV including the MUSE system) system including more scanning lines than these systems. Can also be adopted.

(5) Relation between scanning signal and scanning signal wiring and spacer position The driving method of the element is a) when the driving element applied voltage is higher than the non-driving element applied voltage, and b) when the driving element applied voltage is not applied. The voltage can be roughly classified into two types when the applied voltage is lower than the applied voltage. Here, the position of the scanning signal wiring and the position of the spacer will be described with reference to the simplified diagrams 1a and 1b showing the positional relationship between the scanning signal wiring, the element and the spacer. Here, 1 of 111 is a driving element and 2 of 111 is a non-driving element, which are connected to the scanning signal wirings 13 and 2 and the image signal wiring (not shown), respectively. Further, at the moment shown in the figure, the spacer is assumed to be positioned above the scanning signal wiring 13.

In the case of a) above, 1 of the driving element 111 is used.
The scanning signal voltage applied to 1 of the scanning signal wiring 13 for driving the driving signal is larger than the voltage applied to 2 of 13 and the electric field in the vicinity of 1 of the driving element 111 is applied to the equipotential line 25a of FIG. 1a. As shown, the electron beam 112a emitted from the driving element 111 takes an orbit as shown. Therefore, the spacer is located on the scanning signal wiring 2 and further on the side away from the element 111 connected to the scanning signal wiring 13.

In the case of b), the scanning signal voltage applied to 1 of the scanning signal wiring 13 for driving 1 of the driving element 111 is smaller than the voltage applied to 2 of 13 and the driving signal of 1 of the driving element 111 is 1. The electric field in the vicinity becomes as shown by b of the equipotential line 25 in FIG. 1b, and the b of the electron beam 112 emitted from 1 of the driving element 111 takes a trajectory as shown. Therefore, the spacer is located on the scanning signal wiring 2 and closer to the element 111 connected to the scanning signal wiring 13.

Further, the positional relationship will be described with reference to FIG. Here, 30 is a face plate including a phosphor and a metal back, 31 is a rear plate including an electron source substrate, 20 is a spacer, 13 is a scanning signal wiring, 111 is an element, and 112 is an electron beam. At this time, the distance between the element centers and the distance between the scanning signal wiring centers are a, the width of the scanning signal wirings is e, the thickness of the spacers located on the wirings is f, the beam deviation amount is c, and the beam spot diameter is Be b.
At this time, the beam deviation amount c and the spot diameter b, which change depending on the driving condition (Va, Vf) and the acceleration distance d, are measured in advance, and the position c of the beam end with respect to the element center is measured.
+ B / 2 is the distance from the element center to the spacer surface (a-
When it is larger than f) / 2, the spacer must be displaced from the center of the scanning signal wiring 13 according to the above a) and b). In addition, the range in which the spacer 20 is displaced is such that the spacer 20 is always in contact with the scanning signal wiring 13.

[0154]

EXAMPLES The present invention will be described in more detail below with reference to examples.

In each of the embodiments described below, as a multi-electron beam source, N × M pieces (N = 307) of the above-mentioned type having an electron emitting portion in the conductive fine particle film between electrodes are used.
2, M = 1024), a multi-electron beam source was used in which matrix wiring (see FIGS. 6 and 10) was formed by M row-directional wirings and N column-directional wirings.

An appropriate number of spacers are arranged to obtain the atmospheric pressure resistance of the image forming apparatus.

(Embodiment 1) This embodiment will be described with reference to FIG. 30 is a face plate including a phosphor and a metal back, 31 is a rear plate including an electron source substrate, 20 is a spacer, 13 is a scanning signal wiring, 111 is an element, 112
Is an electron beam. First, the element center distance and the scanning signal wiring center distance a are 700 μm, the width e of the scanning signal wiring is 300 μm, the thickness f of the spacers located on the wiring is 200 μm, the inner surface of the face plate 30 and the rear surface. The distance between the inner surfaces of the plates 31 was 4 mm, the accelerating voltage Va was 5 kV, -7 V was applied to the scanning signal wiring 1 and +7 V was applied to the image signal wiring (not shown), and the element voltage was 14 V. The other 2 of the scanning signal wiring 13 is set to 0 V so that the device voltage does not exceed the electron emission threshold voltage. The beam diameter at this time and the amount of deviation of the beam from the center of the element were examined. The beam diameter b is about 540 μm, and the deviation amount c of the beam center in the scanning direction is
Is about 15 μm. Therefore, the position (b / 2 + c =) 285 μm of the beam end as viewed from the element center is larger than the distance of about 250 μm from the element center to the spacer end, and the beam collides with the spacer. Actually, a slight decrease in brightness was observed only in the vicinity of the spacer. Further, the spacer has a maximum of 50 μm from the center because of the relationship between the thickness f and the width e of the scanning signal wiring
You can move m.

Therefore, when the spacers are arranged so as to be displaced by about 40 μm in the beam shifting direction, no adverse effect is exerted on either side of the spacers, no decrease in brightness is observed, and an even image can be obtained. It was

(Example 2) The difference from Example 1 is that the thickness f of the spacer is 100 μm, the distance between the element centers, the distance a between the scanning signal wirings is 525 μm, and the acceleration voltage Va is 8 k.
That is V. At this time, the position of the beam end seen from the center of the element is about 230 μm, which is larger than the distance from the element center to the end of the spacer of about 210, and the beam collides with the spacer. Actually, the brightness was reduced only near the spacer. In addition, the spacer can move up to 100 μm.

Therefore, when the spacers were arranged so as to be displaced by about 30 μm in the beam shifting direction, no reduction in brightness was observed, there was no unevenness, and a higher-definition image than in Example 1 could be obtained. .

(Embodiment 3) The difference from Embodiment 1 is that the distance between element centers and the distance a between scanning signal wirings are 525 μm.
m, and the acceleration distance d was 3 mm. At this time,
The beam diameter b is about 400 μm, and the deviation amount c of the beam center in the scanning direction is about 10 μm. Therefore, the position of the beam end seen from the element center is about 210 μm, which is larger than the distance from the element center to the spacer end of about 160 μm. The beam strikes the spacer. Actually, the brightness was reduced only near the spacer. In addition, the spacer can move up to 50 μm.

Therefore, when the spacers were arranged so as to be displaced by about 50 μm in the beam shifting direction, no deterioration in brightness was observed, no unevenness was observed, and a higher-definition image than in Example 1 could be obtained. .

[0163]

As described above, according to the present invention, by arbitrarily designing the position of the spacer within the width of the scanning signal wiring in accordance with the trajectory of the electron beam, it is possible to prevent a decrease in brightness and to display a clear image. It has become possible.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing a positional relationship between a scanning signal wiring and a spacer according to the present invention.

FIG. 2 is a diagram showing an example of a conventionally known surface conduction electron-emitting device.

FIG. 3 is a diagram showing an example of a conventionally known FE type element.

FIG. 4 is a diagram showing an example of a conventionally known MIM type element.

FIG. 5 is a perspective view in which a part of the display panel of the image display device is cut away.

FIG. 6 is a perspective view of the image display device according to the embodiment of the present invention with a part of the display panel cut away.

FIG. 7 is a cross-sectional view taken along the line AA ′ of the display panel that is the embodiment of the present invention.

FIG. 8 is a graph showing typical characteristics of the surface conduction electron-emitting device used in this example.

FIG. 9 is a schematic sectional view of an image display device of the present invention.

FIG. 10 is a plan view of the substrate of the multi-electron beam source used in this example.

FIG. 11 is a plan view (a) and a cross-sectional view (b) of the planar surface conduction electron-emitting device used in this example.

FIG. 12 is a plan view illustrating a phosphor array of a face plate of the display panel of the present invention.

FIG. 13 is a diagram for explaining another configuration example of the phosphor.

FIG. 14 is an AA ′ of a display panel that is an embodiment of the present invention.
Cross section

FIG. 15 is a cross-sectional view showing a manufacturing process of the planar surface conduction electron-emitting device of the present invention.

FIG. 16 is a diagram showing applied voltage waveforms during energization forming processing.

FIG. 17 is a cross-sectional view of a vertical surface conduction electron-emitting device used in this example.

FIG. 18 is a sectional view showing a manufacturing process of a vertical surface conduction electron-emitting device of the present invention.

FIG. 19 is a block diagram showing a schematic configuration of a drive circuit of an image display device that is an embodiment of the present invention.

FIG. 20 shows a display panel AA ′ that is an embodiment of the present invention.
Cross-sectional schematic diagram

FIG. 21 is a partial cross-sectional view of the substrate of the multi-electron beam source used in this example.

FIG. 22 is a waveform (a) of applied voltage during energization activation processing,
The figure which shows the change (b) of emission current Ie.

[Explanation of symbols]

11 board 13, 13 0, 13 1 and 2 2 Scan signal wiring 15 Rear plate 16 Side wall 17 Face plate 18 phosphor 19 metal back 20 spacers 25 a, b isopotential lines Two elements, 111 and 111 and 1111, 112,112 1,112 2 electron beams 30 Face plate including phosphor and metal back 31 Rear plate including substrate 1011 substrate 1012 Cold cathode device 1013 row direction wiring 1014 Column direction wiring 1015 Rear plate 1016 Side wall 1017 face plate 1018 phosphor 1019 Metal back 1020 spacer 1001 substrate 1102, 1103 Element electrodes 1104 Conductive thin film 1105 Electron emission unit 1113 thin film 1010 Black conductive material 1041 Bonding material 1110 Forming power supply 1111 ammeter 1112 Power supply for activation 1114 Anode electrode 1115 DC high voltage power supply 1116 ammeter 1201 substrate 1202, 1203 Element electrodes 1204 Conductive thin film 1205 electron emission unit 1206 Step forming member 1701 display panel 1702 scanning circuit 1703 Control circuit 1704 shift register 1705 line memory 1706 Sync signal separation circuit 1707 Modulation signal generator 3001 substrate 3004 Conductive thin film 3005 Electron emission unit 3010 substrate 3011 Emitter wiring 3012 Emitter cone 3013 insulating layer 3014 Gate electrode 3020 substrate 3021, 3023 electrodes 3022 Insulation layer 3111 substrate 3112 Cold cathode device 3113 Row direction wiring 3114 Column direction wiring 3115 Rear plate 3116 Side wall 3117 face plate 3118 phosphor 3119 Metal back 3120 spacer

Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) H01J 31/12 H01J 29/04 H01J 29/87

Claims (7)

(57) [Claims] 1. A plurality of electron-emitting devices are connected to each
Cage, a plurality of said plurality of electron-emitting devices selected voltage and the scanning signal line for applying a non-selection voltage voltage is smaller than the selection voltage, the plurality of electron-emitting devices of each
Placed on the board so that it is located on the same side as the scan signal wiring
And the intervals of the plurality of scanning signal wirings are the same.
And electron emission connected to each scan signal wiring
An electron source having the same distance between the elements, a face plate arranged facing the substrate and having an acceleration electrode for accelerating an electron beam, arranged between the substrate and the face plate, and An image forming apparatus having a supporting member arranged on the scanning signal wiring, wherein the center of the supporting member is for the scanning signal in a direction away from the electron-emitting device connected to the scanning signal wiring in which the supporting member is arranged. An image forming apparatus characterized by being displaced from the center of wiring. 2. The center of the electron-emitting device is before adjoining
The image forming apparatus according to claim 1, wherein an amount δ that is located at the center between the scanning signal wirings and that shifts the center of the supporting member from the center of the scanning signal wirings satisfies the following relationship. (Ef) / 2 ≧ δ ≧ (c + b / 2)-{(af) /
2} c = 2Kd√ {Vf / (Va-Vf)}, e> f, a>
f, a> e, Va> Vf a: distance between the centers of the scanning signal wirings b: spot diameter of the electron beam c: deviation amount of the electron beam trajectory d: distance e between the substrate and the face plate : Width of the scanning signal wiring f: thickness of the supporting member Vf: device voltage Va applied to the electron-emitting device: acceleration voltage K applied to the acceleration electrode K: proportional constant 3. A plurality of electron-emitting devices are connected to each,
A plurality of said plurality of selected voltages to the electron-emitting device and the said selection voltage the scanning signal line for applying a non-selection voltage is a voltage larger than the scanning the plurality of electron-emitting devices of each
It is placed on the board so that it is located on the same side as the signal wiring.
And the intervals of the plurality of scanning signal wirings are the same.
An electron-emitting device connected to each scanning signal wiring together with
An electron source having the same distance, a face plate arranged facing the substrate and having an accelerating electrode for accelerating an electron beam, and a face plate arranged between the substrate and the face plate. In an image forming apparatus having a supporting member arranged on the scanning signal wiring, the center of the supporting member is adjacent to the scanning signal wiring on which the supporting member is arranged and is away from the unconnected electron-emitting device. An image forming apparatus, wherein the scanning signal wiring is displaced from the center. 4. The center of the electron-emitting device is before adjoining.
The image forming apparatus according to claim 3, wherein an amount δ that is located at the center between the scanning signal wirings and that shifts the center of the support member from the center of the scanning signal wirings satisfies the following relationship. (Ef) / 2 ≧ δ ≧ (c + b / 2)-{(af) /
2} c = 2Kd√ {Vf / (Va-Vf)}, e> f, a>
f, a> e, Va> Vf a: distance between the centers of the scanning signal wirings b: spot diameter of the electron beam c: deviation amount of the electron beam trajectory d: distance e between the substrate and the face plate : Width of the scanning signal wiring f: thickness of the supporting member Vf: device voltage Va applied to the electron-emitting device: acceleration voltage K applied to the acceleration electrode K: proportional constant 5. The image forming apparatus according to claim 1, wherein the support member is a conductive support member. 6. The image forming apparatus according to claim 1, wherein the electron-emitting device is an electron-emitting device including a conductive film having an electron-emitting portion between device electrodes. 7. The image forming apparatus according to claim 6, wherein the electron-emitting device is a surface conduction electron-emitting device.