JPH0945222A - Electron emitting element, and electron source using it, and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electron emitting element without deterioration and equal in electron emission characteristic, being used suitably for as the electron beam source of an image forming device, etc. SOLUTION: An electron emitting element has a conductive film 3 consisting of a fine particle film where an electron emitting part 2 is made, between electrodes 4 and 5. At this time, the thickness t1 of the fine particle film and the thickness t2 of the electrode fulfills the relation of t1 <=t2 , and besides the average grain diameter ϕof each fine particle constituting the fine particle film fulfills the relation of t2 >=ϕ.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention particularly relates to an image of a cold cathode type electron-emitting device, an electron source in which a large number of such devices are arranged, and an image of a display device, an exposure device or the like constructed by using the electron source. Forming apparatus

[0002]

2. Description of the Related Art Conventionally, two types of electron-emitting devices are known, which are a thermoelectron-emitting device and a cold cathode electron-emitting device. Field emission type (hereinafter, referred to as "FE")
Type ". ), Metal / insulating layer / metal type (hereinafter referred to as “MI
It is called "M type". ) And surface conduction electron-emitting devices.

[0003] As an example of the FE type, W. P. Dyke
and W. W. Dolan, “Field Em
"Ission", Advance in Elect
ron Physics, 8, 89 (1956) or C.I. A. Spindt, “Physical
Properties of thin-filmfi
eld emission cathodes wit
h mollybdenum cones ”, J. A.
ppl. Phys. , 47, 5248 (1976)
And the like are known.

An example of the MIM type is C.I. A. Mea
d, “Operation of Tunnel-Em
"Ission Devices", J. Appl.
Phys. , 32,646 (1961) and the like are known.

As an example of the surface conduction electron-emitting device,
M. I. Elinson, Radio Eng.
Electron Phys. , 10, 1290 (1
965) and the like.

[0006] The surface conduction electron-emitting device utilizes a phenomenon in which electrons are emitted by passing a current through a small-area thin film formed on an insulating substrate in parallel with the film surface. Examples of the surface conduction electron-emitting device include a device using an SnO ₂ thin film by Elinson et al. And a device using an Au thin film [G. Dittmer: "Thin Solid
Films ", 9, 317 (1972)], In ₂
O ₃ / SnO ₂ thin film [M. Hartwell
and C.I. G. FIG. Fonstad: "IEEE T
rans. ED Conf. , 519 (197
5)], using a carbon thin film [Hisashi Araki et al .: Vacuum,
26, No. 1, p. 22 (1983)].

The surface conduction electron-emitting device utilizes a phenomenon in which electron emission occurs when a current is applied to a conductive film formed on an insulating substrate in parallel with the film surface.

As a typical configuration example of the surface conduction electron-emitting device, a conductive film such as a metal oxide which connects between a pair of device electrodes provided on an insulating substrate is referred to as forming in advance. The thing which formed the electron emission part by the electricity supply process is mentioned. Forming is performed by applying a DC voltage or a very slow rising voltage across the conductive film, for example, 1 V /
A process that is usually performed by applying and applying a rising voltage for about 1 minute to locally destroy, deform or alter the conductive film to change the structure and form an electron-emitting portion in an electrically high resistance state. Is. The electron emission is performed from the vicinity of the crack generated in the electron emitting portion by applying a voltage to the conductive film in which the electron emitting portion is formed and flowing a current.

Since the surface conduction electron-emitting device has a simple structure and is easy to manufacture, it has an advantage that a large number of arrays can be formed over a large area. Therefore, various applications for utilizing this feature are being researched. For example, it can be used for an image forming apparatus such as a display device.

Conventionally, as an example in which a large number of surface conduction electron-emitting devices are formed in an array, surface conduction electron-emitting devices are arranged in parallel and both ends (both device electrodes) of each surface conduction electron-emitting device are wired. An electron source in which a large number of rows connected to each other (also referred to as common wiring) is arranged (also referred to as a ladder arrangement) (Japanese Patent Laid-Open No. 64-31332 and 1-283).
749, and 2-257552). Further, particularly in the case of a display device, a large number of surface conduction electron-emitting devices can be used as a self-luminous display device that can be a flat panel display device similar to a display device using liquid crystal and does not require a backlight. A display device has been proposed in which an arranged electron source is combined with a phosphor that emits visible light when irradiated with an electron beam from the electron source (US Pat. No. 506).
No. 6883).

[0011]

In the conventional surface conduction electron-emitting device described above, a conductive film 3 is formed between electrodes (device electrodes) 4 and 5 and on the electrodes as shown in FIG. The contact resistance between the electrode and the conductive film,
That is, step coverage becomes a problem. Therefore, similarly to the generally known thin film and the step coverage rule of the thin film, the film thickness t ₁ of the conductive film 3 is made larger than the thickness t ₂ of the electrodes 4 and 5.

However, when the electron-emitting portion 2 is formed by applying a current to the conductive film as described above, a very large current flows during the current processing because the conductive film is thick, and heat is generated at this time. There is a drawback that the electron emitting portion is easily deteriorated due to the breakage of the substrate 1.

Therefore, when a plurality of the above-mentioned elements are formed, the electric characteristics of the respective elements are varied, and in particular, in the above-mentioned image forming apparatus, there are problems such as uneven brightness of the phosphor and flickering of the display. Was there.

Therefore, it is an object of the present invention to provide an electron-emitting device which prevents deterioration of the electron-emitting portion and exhibits stable electric characteristics. Another object of the present invention is to provide an electron source in which the characteristic variation among the electron-emitting devices is extremely small, and further, an image forming apparatus in which the brightness unevenness of the fluorescent image and the flicker of the display are extremely small.

[0015]

The constitution of the present invention made to achieve the above object is as follows.

That is, the first aspect of the present invention is an electron-emitting device having a conductive film having an electron-emitting portion formed between electrodes, wherein the conductive film is a fine particle film, and the thickness t of the fine particle film is t. ₁ and the thickness t _{2 of the} electrode satisfy the relationship of t ₁ ≦ t ₂ , and the average particle diameter φ of the fine particles forming the fine particle film.
Relates to an electron-emitting device characterized by satisfying a relation of t ₂ ≧ φ.

The electron-emitting device according to the first aspect of the present invention further has a feature that "the contact resistance between the fine particle film and the electrode and the sheet resistance of the fine particle film satisfy the relationship of contact resistance <sheet resistance". It also includes that the sheet resistance of the fine particle film is in the range of 10 ³ to 10 ¹⁰ Ω / □ and that it is a surface conduction electron-emitting device.

A second aspect of the present invention relates to an electron source comprising the electron-emitting device according to the first aspect of the present invention and a driving means for driving the electron-emitting device.

The second electron source of the present invention is further characterized in that it is "an electron source having at least one element row in which a plurality of electron-emitting devices are connected in parallel".
It is also included that "a plurality of element rows in which a plurality of electron-emitting devices are connected are electron sources arranged in a matrix".

Further, in a third aspect of the present invention, the electron emitting element of the first aspect of the present invention, the image forming member, and irradiation of the electron beam emitted from the electron emitting element to the image forming member are used as information signals. The present invention relates to an image forming apparatus having a driving unit that controls the image forming apparatus according to the present invention.

The image forming apparatus according to the third aspect of the present invention is further characterized in that "at least one element array in which a plurality of the electron-emitting devices are connected in parallel is provided".
It also includes "a plurality of element rows in which a plurality of the electron-emitting elements are connected are arranged in a matrix" and "the image forming member is a phosphor".

[0022]

As described above, the present invention relates to a novel structure of an electron-emitting device, an electron source including a plurality of the electron-emitting devices, and an image forming apparatus using the same. The configuration and operation of will be further described below.

The electron-emitting device according to the present invention is classified into the cold cathode type electron-emitting device as described above. Among them, the surface conduction type electron-emitting device is particularly preferable from the viewpoint of electron emission characteristics and the like. Is. Therefore, the surface conduction electron-emitting device will be described below as an example.

1 (a) and 1 (b) are views showing the basic structure of a surface conduction electron-emitting device of the present invention.
Reference numeral 1 is a substrate, 2 is an electron emitting portion, 3 is a conductive film made of a fine particle film, and 4 and 5 are electrodes (element electrodes).

The substrate 1 is, for example, quartz glass or Na.
And glass having reduced impurity content such as glass, blue plate glass, a laminate obtained by laminating SiO ₂ on a blue plate glass by a sputtering method or the like, and ceramics such as alumina.

As the material of the device electrodes 4 and 5 facing each other,
Common conductor materials are used, such as Ni, Cr, Au,
Metals or alloys such as Mo, W, Pt, Ti, Al, Cu, Pd, and Pd, Ag, Au, RuO ₂ , Pd-Ag
Printed conductors composed of metals or metal oxides and glass and the like, transparent conductors such as In ₂ O ₃ —SnO ₂ , and semiconductor conductor materials such as polysilicon are appropriately selected.

The element electrode interval L, the element electrode length W, the shape of the conductive film 3 and the like are designed according to the applied form.

The device electrode spacing L is preferably several hundred angstroms to several hundreds of micrometers, more preferably several micrometers to several tens of micrometers depending on the voltage applied between the device electrodes 4 and 5. .

The device electrode length W is preferably several micrometers to several hundreds of micrometers in view of the resistance value of the electrodes and electron emission characteristics, and the device electrode thickness t ₂
Is from a few hundred Angstroms to a few micrometers.

The conductive film 3 is composed of a fine particle film made of fine particles and has a laminated portion on the device electrodes so as to be electrically connected to the device electrodes 4 and 5.

The fine particle film is a film in which a plurality of fine particles are aggregated, and as a fine structure thereof, not only the fine particles are individually dispersed and arranged but also the fine particles are adjacent to each other or overlap each other (some fine particles). Also includes the case where they are aggregated to form an island-like structure as a whole).

[0032] In the electron-emitting device of the present invention, the thickness t ₂ of the thickness t ₁ and the electrodes 4 and 5 of the fine particle layer 3 is t ₁ ≦ t ₂
And the average particle diameter φ of the fine particles forming the fine particle film 3 is t ₂
The relationship of ≧ φ is satisfied. That is, the electrodes 4 and 5 are
It has a thickness not less than the average particle diameter of the fine particles of the fine particle film 3 and not less than the thickness of the fine particle film 3.

In the case of general thin films, in order to make a sufficient electrical connection in their laminated portions, it is necessary to laminate them with a film thickness equal to or more than that of the lower layer (preferably about 3 times). However, by adopting the fine particle film as the conductive film as in the present invention, the conductive film 3 and the electrodes 4 and 5 can be sufficiently electrically connected by satisfying the above relationship. .

The term "fine particles" is frequently used in this specification, and the meaning thereof will be described.

Small particles are called "fine particles", and particles smaller than this are called "ultrafine particles". It is widely known that particles smaller than "ultrafine particles" and having a number of atoms of about several hundreds or less are called "clusters".

However, each boundary is not strict, and changes depending on what kind of property is focused on for classification. Further, “fine particles” and “ultrafine particles” may be collectively referred to as “fine particles”, and the description in this specification is in line with this.

For example, in "Experimental physics course 14 Surfaces and fine particles" (edited by Yoshio Kinoshita, published by Kyoritsu Shuppan on September 1, 1986), "fine particles in this paper have a diameter of about 2-3 μm to 10 nm. Up to about 10 nm, especially when referred to as ultrafine particles, the particle size is from about 10 nm to
It means up to about m. It is not exactly strict because both are collectively written as fine particles, but it is a rough guide. When the number of atoms constituting a particle is from 2 to several tens to several hundreds, it is called a cluster. (Page 195, lines 22 to 26).

In addition, the definition of "ultrafine particles" in the "Hayashi / ultrafine particle project" of the New Technology Development Corporation has the following lower limit of the particle size.

In the "Ultrafine particle project" (1981-1986) of the Creative Science and Technology Promotion System, particles having a particle size (diameter) in the range of approximately 1 to 100 nm are called "ultrafine particles". Then, one ultrafine particle is about 100-
It is an aggregate of about 10 ⁸ atoms. Ultra-fine particles are large to giant particles on an atomic scale. ("Ultra Fine Particles-Creative Science and Technology" Hayashi Tax, Ryoji Ueda, Akira Tazaki
Edited by Mita Shuppan 1988, page 2, lines 1 to 4) /
"A particle even smaller than an ultrafine particle, that is, a single particle composed of several to several hundred atoms, is usually called a cluster" (ibid., Page 2, lines 12 to 13).

[0040] Based on the general notation as described above,
In the present specification, “fine particles” are an aggregate of a large number of atoms and molecules, and the lower limit of the particle size is several Å to 10 Å, and the upper limit is several μm.
I will refer to something of a degree.

As the material for forming the conductive film (fine particle film) 3, for example, Pd, Pt, Ru, Ag, Au, Ti,
In, Cu, Cr, Fe, Zn, Sn, Ta, W, Pb
Metals such as PdO, SnO ₂ , In ₂ O ₃ , PbO, S
oxides such as b ₂ O ₃ , HfB ₂ , ZrB ₂ , LaB ₆ ,
Borides of CeB ₆ , YB ₄ , GdB _4, etc., TiC, Zr
Carbides such as C, HfC, TaC, SiC, WC, Ti
Nitrides such as N, ZrN, and HfN; semiconductors such as Si and Ge; and carbon.

The thickness t ₁ of the fine particle film is equal to or larger than the average particle diameter of the fine particles and varies depending on the fine particle material, but the film thickness is equal to or smaller than the electric resistance of the continuous film, that is, a sheet resistance of 10 ³ to 10 ¹⁰ Ω / □. It is preferable that the film has a film thickness.

A crack is included in the electron emitting portion 2, and the electron emission is performed from the vicinity of this crack. The electron-emitting portion 2 including the crack and the crack itself have a thickness, film quality,
It is formed depending on a material and a manufacturing method such as forming conditions described later. Therefore, the position and shape of the electron-emitting portion 2 are not limited to the position and shape as shown in FIG.

The inside of the crack may have conductive fine particles having a particle diameter of several angstroms to several hundred angstroms. The conductive fine particles are similar to some or all of the elements of the material constituting the conductive film 3. In addition, the electron emitting portion 2 including a crack and the conductive film 3 in the vicinity thereof
Has a film containing carbon as a main component.

The electron-emitting device shown in FIG. 1 is only one embodiment of the present invention, and as will be apparent from the embodiments described later, the electron-emitting device of the present invention is limited to such an embodiment. It is not something that will be done.

By adopting the above structure, the electron-emitting device of the present invention can be made into an electron-emitting device having no deterioration of the electron-emitting portion and having extremely small variation in characteristics between devices, as will be described in detail later. it can.

Various methods are conceivable as a method of manufacturing the basic structure of the surface conduction electron-emitting device suitable for the present invention, and an example thereof will be described with reference to FIG. In FIG. 4, the same reference numerals as those in FIG. 1 denote the same members.

1) After the substrate 1 is thoroughly washed with a detergent, pure water and an organic solvent, a device electrode material is deposited by a vacuum deposition method, a sputtering method or the like, and then on the surface of the substrate 1 by a photolithography technique or the like. The device electrodes 4 and 5 are formed (FIG. 4A).

2) The element electrode 4 is formed by applying an organic metal solution on the substrate 1 on which the element electrodes 4 and 5 are provided and leaving it to stand.
And the element electrode 5 are connected to each other to form an organic metal film. still,
The organic metal solution is a solution of an organic compound whose main element is a metal of the constituent material of the conductive film 3 described above. After that, the organic metal film is heated and baked, and is patterned by lift-off, etching or the like to form the conductive film 3 made of a fine particle film having a desired pattern shape (FIG. 4B).

Although the method of coating the organic metal solution has been described here, the method is not limited to this, and examples thereof include a vacuum vapor deposition method, a sputtering method, a chemical vapor deposition method, a dispersion coating method, a dipping method and a spinner method. It is also possible to form an organic metal film.

3) Subsequently, a forming process by energization is performed.

When a power supply (not shown) is applied between the device electrodes 4 and 5, an electron emitting portion 2 having a changed structure is formed at the portion of the conductive film 3 (FIG. 4C). By this energization treatment, the conductive film 3 is locally destroyed, deformed or denatured, and the site where the structure is changed is the electron emitting portion 2.

According to the above-described structure of the electron-emitting device of the present invention, the contact resistance between the electrodes 4 and 5 and the conductive film 3,
Since the sheet resistance of the conductive film 3 has a relationship of contact resistance << sheet resistance, the voltage drop in the laminated portion is extremely small. That is, since the voltage applied between the electrodes 4 and 5 acts so as to be substantially applied to the electron emitting portion 2, the electrodes 4 and 5 and the conductive film 3 are caused by the maximum current during forming and the current flowing during driving. No damage will occur at the contact part of the. Further, the conductive film 3 has electrodes 4 and 5
Forming a sheet resistance of 10 ³ to 10 ¹⁰ Ω / □ in between can prevent excessive heat generation during energization processing and prevent deterioration of the electron emission portion due to destruction of the substrate due to this, and further, When applied to the electron source and the image forming apparatus described later,
Since there is no characteristic variation between elements, not only an electron source having uniform characteristics can be obtained, but also an image with extremely small unevenness in brightness and flickering in display can be formed even when forming an image.

FIG. 5 shows an example of the voltage waveform of energization forming.

The voltage waveform is particularly preferably a pulse waveform,
There are a case where a voltage pulse whose pulse peak value is a constant voltage is continuously applied (FIG. 5A), and a case where a voltage pulse is applied while increasing the pulse peak value (FIG. 5B).

First, the case where the pulse peak value is a constant voltage will be described with reference to FIG.

In FIG. 5A, T1 and T2 are the pulse width and the pulse interval of the voltage waveform. For example, T1 is 1 microsecond to 10 milliseconds and T2 is 10 microseconds to 100.
The peak value (peak voltage at the time of forming) is set to millisecond and is appropriately selected according to the form of the electron-emitting device described above.
It is applied for several seconds to several tens of minutes in a vacuum atmosphere having an appropriate degree of vacuum of about 0 −5 torr. The voltage waveform to be applied is not limited to the illustrated triangular wave, and a desired waveform such as a rectangular wave may be used, and the crest value, pulse width, pulse interval, etc. are also limited to the above values. However, a desired value can be selected according to the resistance value of the electron-emitting device so that the electron-emitting portion 2 can be formed favorably.

Next, the case of applying the voltage pulse while increasing the pulse crest value will be described with reference to FIG.

T1 and T2 in FIG. 5B are shown in FIG.
As in (a), the peak value (peak voltage at the time of forming) is increased by, for example, about 0.1 V steps,
Application is performed in an appropriate vacuum atmosphere similar to the description of FIG.

During the pulse interval T2, the element current is measured at a voltage that does not locally damage, deform or alter the conductive film 3, for example, a voltage of about 0.1 V to obtain a resistance value, for example, 1 M. Forming is preferably terminated when the resistance is equal to or higher than ohms.

The steps from the forming step onward can be performed in a measurement and evaluation system as shown in FIG. This measurement evaluation system will be described.

6, the same reference numerals as those in FIG. 1 indicate the same members. Further, 51 is a power supply for applying a device voltage Vf to the device, 50 is an ammeter for measuring a device current If flowing through the conductive film 3 between the device electrodes 4 and 5, and 54 is an electron emitting portion 2. An anode electrode for trapping the emission current Ie generated, 53 is a high-voltage power supply for applying a voltage to the anode electrode 54, 52 is an ammeter for measuring the emission current Ie emitted from the electron emission portion 2, 55 Is a vacuum device,
56 is an exhaust pump.

The electron-emitting device, the anode electrode 54, etc. are installed in a vacuum device 55, and this vacuum device 55 is equipped with necessary equipment such as a vacuum gauge (not shown) so that the electron-emitting device can be operated under a desired vacuum. It is possible to measure and evaluate.

The exhaust pump 56 is composed of a normal high vacuum system such as a turbo pump and a rotary pump, and an ultra high vacuum system including an ion pump.
The entire vacuum device 55 and the substrate 1 of the electron-emitting device are
The heater can heat up to about 200 ° C. This measurement and evaluation system configures the display panel and its inside as the vacuum device 55 and its inside at the stage of assembling the display panel as will be described later, so that the measurement and evaluation in the forming step and the subsequent steps described later are performed. It is applied to processing.

4) Next, it is preferable to perform an activation treatment for depositing carbon and a carbon compound on the region including the electron emitting portion 2.

As a method of depositing carbon and a carbon compound in the region including the electron emitting portion 2, a usual method such as vacuum vapor deposition, sputtering, CVD, ion plating can be used, but a vacuum atmosphere in which an organic substance exists. Below, the method of applying a voltage pulse between the device electrodes 4 and 5 is more preferable because it is simple. In particular, in the case of the surface conduction electron-emitting device, this method significantly improves the electron emission characteristics.

The vacuum atmosphere in which the organic substance is present in the activation treatment step is formed by utilizing the organic gas remaining in the atmosphere when the inside of the vacuum container is evacuated using, for example, an oil diffusion pump or a rotary pump. Besides, it can be obtained by introducing a gas of an appropriate organic substance into a vacuum that has been sufficiently evacuated by an ion pump or the like. The preferable gas pressure of the organic substance at this time varies depending on the above-described application form, the shape of the vacuum vessel, the type of the organic substance, and the like, and is appropriately set according to the case. Suitable organic substances include alkanes, alkenes, alkyne aliphatic hydrocarbons, aromatic hydrocarbons, alcohols, aldehydes,
Ketones, amines, phenols, carboxylic acids, organic acids such as sulfonic acids and the like can be mentioned. Specifically, methane, ethane, propane and the like, saturated hydrocarbons represented by C _n H _{2n + 2} , ethylene, Unsaturated hydrocarbons represented by compositional formulas such as propylene and C _n H _2n , benzene, toluene, methanol, ethanol, formaldehyde, acetaldehyde, acetone, methyl ethyl ketone, methylamine, ethylamine, phenol, formic acid, acetic acid, propionic acid, etc. Can be used. By this treatment, carbon or a carbon compound is deposited on the device from the organic substance existing in the atmosphere, and the device current If and the emission current Ie are significantly changed.

The above-mentioned carbon and carbon compound include, for example, graphite (so-called HOPG ', PG (, GC), and HOPG is an almost perfect crystal structure of graphite, P
G indicates that the crystal grains were about 200Å and the crystal structure was slightly disturbed, and GC indicates that the crystal grains were about 20Å and the crystal structure was further disturbed. ) And amorphous carbon (referring to amorphous carbon and a mixture of amorphous carbon and fine crystals of graphite), and the deposited film thickness thereof is preferably 500 angstroms or less, more preferably 300 angstroms or less.

5) It is preferable to carry out a stabilizing process in which the electron-emitting device thus manufactured is driven and operated in a vacuum atmosphere having a vacuum degree higher than those in the forming step and the activation step. More preferably, in a vacuum atmosphere having a high degree of vacuum, after heating at 80 to 150 ° C., the operation is driven.

A vacuum atmosphere having a vacuum degree higher than the vacuum degree in the forming step and the activation step means, for example, about −10
It is a vacuum atmosphere having a vacuum degree of 6th torr or more,
More preferably, it is an ultra-high vacuum system, and the degree of vacuum is such that carbon and carbon compounds are hardly newly deposited.

That is, by encapsulating the electron-emitting device in the above-mentioned vacuum atmosphere, it is possible to suppress further deposition of carbon and carbon compounds, thereby stabilizing the device current If and the emission current Ie. .

The basic characteristics of the surface conduction electron-emitting device obtained as described above will be described below.

The basic characteristics of the surface conduction electron-emitting device described below are that the voltage of the anode electrode 54 of the measurement / evaluation system of FIG. 6 is 1 kV to 10 kV and the distance H between the anode electrode 54 and the surface conduction electron-emitting device is 2 Usually, the measurement is performed by setting the width to 8 mm.

First, the emission current Ie and the device current If,
FIG. 7 shows a typical example of the relationship with the element voltage Vf. still,
In FIG. 7A, since the emission current Ie is significantly smaller than the device current If, it is shown in arbitrary units.

As is apparent from FIG. 7A, the surface conduction electron-emitting device has the following three characteristic characteristics with respect to the emission current Ie.

First, the surface conduction electron-emitting device has a certain voltage (called a threshold voltage: Vt in FIG. 7A).
When the device voltage Vf exceeding h) is applied, the emission current Ie rapidly increases, while at the threshold voltage Vth or less, the emission current Ie is hardly detected. That is, it is a nonlinear element having a clear threshold voltage Vth with respect to the emission current Ie.

Secondly, since the emission current Ie has a characteristic of monotonically increasing with respect to the element voltage Vf (called MI characteristic), the emission current Ie can be controlled by the element voltage Vf.

Thirdly, the emission charge captured by the anode electrode 54 (see FIG. 6) depends on the time for applying the device voltage Vf. That is, the amount of charges captured by the anode electrode 54 can be controlled by the time for which the device voltage Vf is applied.

The emission current Ie is MI with respect to the device voltage Vf.
At the same time as having the characteristics, the element current If may also have the MI characteristics with respect to the element voltage Vf. An example of the characteristic of such a surface conduction electron-emitting device is the characteristic shown in FIG. On the other hand, as shown in FIG. 7B, the device current I
f is a voltage control type negative resistance characteristic (V
In some cases, it may be referred to as a CNR characteristic). Which characteristic is exhibited depends on the manufacturing method of the surface conduction electron-emitting device and the measurement conditions at the time of measurement. However, even in the surface conduction electron-emitting device in which the device current If has the VCNR characteristic with respect to the device voltage Vf, the emission current Ie has the MI characteristic with respect to the device voltage Vf.

Due to the characteristic characteristics of the surface conduction electron-emitting device according to the present invention as described above, even in an electron source or an image forming apparatus in which a plurality of devices are arranged, the amount of emitted electrons can be easily controlled according to an input signal. Therefore, it can be applied to various fields.

Next, as an example of the electron source of the present invention, an electron source in which a plurality of the surface conduction electron-emitting devices described above are arranged will be described. First, the arrangement method of the surface conduction electron-emitting devices will be described.

As a method of arranging the surface conduction electron-emitting devices in the electron source of the present invention, in addition to the trapezoidal arrangement as described in the section of the prior art, n Y's are arranged on m X-direction wirings. There is an arrangement method in which directional wirings are provided via an interlayer insulating layer and an X-direction wiring and a Y-direction wiring are connected to a pair of device electrodes of a surface conduction electron-emitting device, respectively. This is hereinafter referred to as a simple matrix arrangement. First, the simple matrix arrangement will be described in detail.

According to the basic characteristics of the surface conduction electron-emitting device described above, the emitted electrons in the surface conduction electron-emitting device arranged in the simple matrix are generated between the opposing device electrodes at a voltage exceeding the threshold voltage. It can be controlled by the peak value and pulse width of the applied pulsed voltage. On the other hand, almost no electrons are emitted below the threshold voltage. Therefore, even when a large number of surface conduction electron-emitting devices are arranged, if the pulsed voltage is appropriately applied to each device, the surface conduction electron-emitting device is selected according to the input signal and the electron emission amount thereof is selected. Can be controlled, and individual surface conduction electron-emitting devices can be selected and driven independently by simple matrix wiring.

The simple matrix arrangement is based on such a principle, and the structure of the electron source having the simple matrix arrangement, which is an example of the electron source of the present invention, will be further described with reference to FIG.

In FIG. 8, the substrate 1 is a glass plate or the like as already described, and the number and shape of the surface conduction electron-emitting devices 104 according to the present invention arranged on the substrate 1 are appropriately set according to the application. It is something.

The m wirings in the X direction 102 have external terminals Dx1, Dx2, ..., Dxm, respectively.
A conductive metal or the like formed on the top by a vacuum deposition method, a printing method, a sputtering method, or the like. In addition, the material, so that the voltage is supplied almost evenly to the large number of surface conduction electron-emitting devices 104,
The film thickness and wiring width are set.

The n Y-direction wirings 103 each have external terminals Dy1, Dy2, ..., Dyn, and are formed similarly to the X-direction wirings 102.

These m X-direction wirings 102 and n Y-wirings
An interlayer insulating layer (not shown) is provided between the direction wirings 103, and is electrically separated to form a matrix wiring. Note that both m and n are positive integers.

The interlayer insulating layer (not shown) is SiO ₂ or the like formed by a vacuum evaporation method, a printing method, a sputtering method or the like, and has a desired shape on the entire surface or a part of the substrate 1 on which the X-direction wiring 102 is formed. In particular, the film thickness, material, and manufacturing method are appropriately set so as to withstand the potential difference at the intersection of the X-direction wiring 102 and the Y-direction wiring 103. The X-direction wiring 102 and the Y-direction wiring 103 are respectively drawn out as external terminals.

Furthermore, the device electrodes (not shown) of the surface conduction electron-emitting device 104 facing each other are m number of X-direction wirings 102.
, N Y-direction wirings 103, a vacuum deposition method, a printing method,
Connection 1 made of a conductive metal or the like formed by a sputtering method or the like
05 are electrically connected.

Here, even if some or all of the constituent elements of the m X-direction wirings 102, the n Y-direction wirings 103, the connection 105, and the opposing element electrodes are the same, Further, they may be different from each other, and are appropriately selected from the above-mentioned material of the element electrode and the like. The wires to these device electrodes may be collectively referred to as device electrodes when the material is the same as the device electrodes. In addition, the surface conduction electron-emitting device 104
May be formed either on the substrate 1 or on an interlayer insulating layer (not shown).

Further, as will be described later in detail, a scanning signal is applied to the X-direction wiring 102 in order to scan the rows of the surface conduction electron-emitting devices 104 arranged in the X-direction according to an input signal. A scanning signal applying means (not shown) is electrically connected.

On the other hand, in the Y-direction wiring 103, a modulation signal (not shown) is applied to modulate each row of the surface conduction electron-emitting devices 104 arranged in the Y-direction according to an input signal. The signal generating means is electrically connected. Further, the drive voltage applied to each surface conduction electron-emitting device 104 is supplied as a difference voltage between the scanning signal and the modulation signal applied to the surface conduction electron-emitting device 104.

Next, an example of the image forming apparatus of the present invention constructed by using the electron source having the above simple matrix arrangement will be described with reference to FIGS. 9 to 11. 9 is a basic configuration diagram of the display panel 201, and FIG. 10 is a fluorescent film 114.
11 is a diagram showing a display panel 201 of FIG.
3 is a block diagram showing an example of a drive circuit for performing television display in accordance with an NTSC television signal. FIG.

In FIG. 9, 1 is a substrate of an electron source in which the surface conduction electron-emitting devices are arranged as described above, 111 is a rear plate to which the substrate 1 is fixed, and 116 is a glass substrate 1.
13 is a face plate in which a fluorescent film 114 and a metal back 115 are formed on the inner surface. Reference numeral 112 denotes a support frame, and frit glass or the like is applied to the rear plate 111, the support frame 112, and the face plate 116, and is applied in the air or in nitrogen. Then, the envelope 118 is formed by baking at 400 to 500 ° C. for 10 minutes or more for sealing.

In FIG. 9, 102 and 103 are a pair of device electrodes 4 and 5 of the surface conduction electron-emitting device 104 (see FIG. 1).
The X-direction wiring and the Y-direction wiring connected to the external terminals Dx1 to Dxm and Dy1 to Dyn, respectively.

The envelope 118 is composed of the face plate 116, the support frame 112 and the rear plate 111 as described above. However, the rear plate 111 is provided mainly for the purpose of reinforcing the strength of the substrate 1. If the substrate 1 itself has sufficient strength, the separate rear plate 111 is unnecessary, and the support frame is directly attached to the substrate 1. Seal 112,
The envelope 118 may be constituted by the face plate 116, the support frame 112, and the substrate 1. Further, by further providing a support (not shown) called a spacer between the face plate 116 and the rear plate 111, the envelope 118 having sufficient strength against atmospheric pressure can be obtained.

In the case of monochrome, the fluorescent film 114 is composed of only the fluorescent substance 122, but in the case of the color fluorescent film 114, depending on the arrangement of the fluorescent substances 122, a black stripe (FIG. 10A) or a black matrix (FIG. 10A). 10
(B)) a black conductive material 121 and a phosphor 122 called
It is composed of The purpose of providing the black stripes and the black matrix is to make the mixed portions between the phosphors 122 of the three primary colors necessary for color display black so that mixed colors and the like are not noticeable, and to reflect external light on the fluorescent film 114. Is to suppress a decrease in contrast due to As a material of the black conductive material 121, not only a material mainly containing graphite, which is often used, but also a material having conductivity and low light transmission and reflection may be used. it can.

As a method of applying the phosphor 122 to the glass substrate 113, a precipitation method or a printing method is used regardless of monochrome or color.

In addition, as shown in FIG.
A metal back 115 is usually provided on the inner surface side of 4.
The purpose of the metal back 115 is to allow the light emitted from the phosphor 122 (see FIG. 10) to the inside of the face plate 11
The mirror 122 is mirror-reflected to improve brightness, acts as an electrode for applying an electron beam accelerating voltage, and protects the phosphor 122 from damage due to collision of negative ions generated in the envelope 118. Etc. The metal back 115 can be manufactured by performing smoothing processing (usually called filming) on the inner surface of the fluorescent film 114 after manufacturing the fluorescent film 114, and then depositing Al by vacuum evaporation or the like.

The face plate 116 may be provided with a transparent electrode (not shown) on the outer surface side of the fluorescent film 114 in order to further enhance the conductivity of the fluorescent film 114.

At the time of performing the above-mentioned sealing, in the case of a color, the phosphors 122 of the respective colors and the surface conduction electron-emitting device 104 must correspond to each other, so that it is necessary to perform sufficient alignment.

The inside of the envelope 118 is evacuated through an exhaust pipe (not shown), and after reaching a predetermined degree of vacuum, it is sealed. Further, a getter process can be performed to maintain the degree of vacuum after the envelope 118 is sealed. This is the envelope 118
Immediately before or after the sealing is performed, a getter (not shown) arranged at a predetermined position in the envelope 118 is heated by resistance heating or high frequency heating to form a vapor deposition film. The getter usually contains Ba or the like as a main component, and is for maintaining a vacuum degree of, for example, 1 × 10 −5 to 1 × 10 −7 torr due to the adsorption action of the vapor deposition film.

In addition, each manufacturing process of the surface conduction electron-emitting device after the above-mentioned forming process is usually performed by the envelope 11
It is performed immediately before or after the sealing of No. 8, and the content thereof is as described above.

The display panel 201 described above is shown in FIG.
Can be driven by a driving circuit as shown in FIG.
In FIG. 11, 201 is a display panel, 202 is a scanning circuit, 203 is a control circuit, 204 is a shift register,
205 is a line memory, 206 is a synchronization signal separation circuit, 2
Reference numeral 07 is a modulation signal generator, and Vx and Va are DC voltage sources.

As shown in FIG. 11, the display panel 20.
1 is connected to an external electric circuit via the external terminals Dx1 to Dxm, the external terminals Dy1 to Dyn, and the high-voltage terminal Hv. Of these, the external terminals Dx1 to Dxm
The surface conduction electron-emitting devices provided in the display panel 201, that is, the group of surface conduction electron-emitting devices arranged in a matrix of m rows and n columns are sequentially driven one row (n elements at a time). A scanning signal for moving is applied.

On the other hand, a modulation signal for controlling the output electron beam of each surface conduction electron-emitting device of one row selected by the scanning signal is applied to the terminal Dy1 to the external terminal Dyn. Further, the high voltage terminal Hv is supplied with a DC voltage of, for example, 10 kV from the DC voltage source Va. This is an accelerating voltage for giving enough energy to excite the phosphor to the electron beam output from the surface conduction electron-emitting device.

The scanning circuit 202 is provided with m switching elements (schematically shown by S1 to Sm in FIG. 11) inside, and each of the switching elements S1 to Sm is an output voltage of the DC voltage source Vx or 0V. One of (ground level) is selected and electrically connected to the external terminals Dx1 to Dxm of the display panel 201. Each of the switching elements S1 to Sm includes a control circuit 203.
It operates on the basis of the control signal Tscan output from the device, and in fact, it can be easily configured by combining elements having a switching function such as an FET.

The DC voltage source Vx in this example has a threshold drive voltage applied to the surface-conduction type electron-emitting devices which are not scanned, based on the characteristics (threshold voltage) of the surface-conduction type electron-emitting devices. It is set to output a constant voltage that is less than or equal to the value voltage.

The control circuit 203 has a function of matching the operation of each part so that an appropriate display is performed based on an image signal input from the outside. The synchronization signal Tsyn sent from the synchronization signal separation circuit 206 described below
Based on c, each control signal of Tscan, Tsft, and Tmry is generated for each unit.

The synchronizing signal separation circuit 206 is a circuit for separating a synchronizing signal component and a luminance signal component from an NTSC television signal input from the outside, and as is well known, a frequency separating (filter) If you use a circuit,
It can be easily configured. Sync signal separation circuit 206
The sync signal separated by is composed of a vertical sync signal and a horizontal sync signal, as is well known. here,
For convenience of explanation, it is shown as Tsync. On the other hand, the luminance signal component of the image separated from the television signal is referred to as D for convenience.
This is shown as an ATA signal. This DATA signal is input to the shift register 204.

The shift register 204 is for serially / parallel converting the DATA signal serially input in time series for each line of the image, and based on the control signal Tsft sent from the control circuit 203. Operate. The control signal Tsft is supplied to the shift register 20.
In other words, the shift clock may be four. Also,
One line of serial / parallel converted image (equivalent to drive data for n elements of surface conduction electron-emitting device)
Data is output from the shift register 204 as n parallel signals Id1 to Idn.

The line memory 205 is a storage device for storing data for one line of an image for a required time,
The contents of Id1 to Idn are stored according to the control signal Tmry sent from the control circuit 203. The stored contents are output as Id'1 to Id'n and input to the modulation signal generator 207.

The modulation signal generator 207 is a signal source for appropriately driving and modulating each of the surface conduction electron-emitting devices according to each of the image data Id'1 to Id'n, and its output signal is , And is applied to the surface conduction electron-emitting device in the display panel 201 through the terminals Dy1 to Dyn.

As described above, the surface conduction electron-emitting device has a clear threshold voltage for electron emission, and electron emission occurs only when a voltage exceeding the threshold voltage is applied. Further, for a voltage exceeding the threshold voltage, the emission current also changes according to the change in the voltage applied to the surface conduction electron-emitting device. Material of surface conduction electron-emitting device,
The value of the threshold voltage and the degree of change of the emission current with respect to the applied voltage may change by changing the configuration and the manufacturing method. In any case, the following can be said.

That is, when a pulsed voltage is applied to the surface conduction electron-emitting device, no electron emission occurs even if a voltage below the threshold voltage is applied, but a voltage exceeding the threshold voltage is applied. If it does, electron emission occurs. At that time, first, it is possible to control the intensity of the output electron beam by changing the peak value of the voltage pulse. Secondly, it is possible to control the total amount of charges of the output electron beam by changing the width of the voltage pulse.

Therefore, as a method of modulating the surface conduction electron-emitting device according to an input signal, there are a voltage modulation method and a pulse width modulation method. In the case of performing the voltage modulation method, the modulation signal generator 207 generates a voltage pulse having a fixed length, and uses a voltage modulation circuit capable of appropriately modulating the pulse peak value according to input data. In the case of performing the pulse width modulation method, the modulation signal generator 207 generates a voltage pulse having a constant peak value, but a pulse width modulation method circuit capable of appropriately modulating the pulse width according to input data. Used.

The shift register 204 and the line memory 20
Reference numeral 5 may be a digital signal type or an analog signal type, as long as it can perform serial / parallel conversion and storage of an image signal at a predetermined speed.

When the digital signal type is used, it is necessary to convert the output signal DATA of the sync signal separation circuit 206 into a digital signal. This can be achieved by providing an A / D converter at the output of the synchronization signal separation circuit 206.

Also in connection with this, the line memory 20
Depending on whether the output signal of 5 is a digital signal or an analog signal,
The circuit provided in modulation signal generator 207 is slightly different.

That is, in the case of the voltage modulation method using a digital signal, for the modulation signal generator 207, for example, a well-known D / A conversion circuit may be used, and an amplification circuit or the like may be added if necessary. In the case of a pulse width modulation method using a digital signal, the modulation signal generator 207 includes, for example, a high-speed oscillator, a counter (counter) for counting the number of waves output from the oscillator, and an output value of the counter and an output value of the memory. It can be easily configured by using a circuit in which comparators for comparison are combined. Further, if necessary, an amplifier for voltage-amplifying the pulse-width-modulated modulation signal output from the comparator to the drive voltage of the surface conduction electron-emitting device may be added.

On the other hand, in the case of the voltage modulation method using an analog signal, the modulation signal generator 207 may be, for example, an amplifier circuit using a well-known operational amplifier or the like, and a level shift circuit or the like may be added if necessary. May be. Further, in the case of the pulse width modulation method using an analog signal, for example, a well-known voltage controlled oscillation circuit (VCO) may be used, and the voltage is amplified to the drive voltage of the surface conduction electron-emitting device as necessary. May be added.

The image forming apparatus according to the present invention having the display panel 201 and the driving circuit as described above has terminals Dx1 to Dx1.
By applying a voltage from Dxm and Dy1 to Dyn, electrons can be emitted from a required surface conduction electron-emitting device, and the metal back 1 is supplied through the high voltage terminal Hv.
15 or a transparent electrode (not shown) is applied with a high voltage to accelerate the electron beam, and the accelerated electron beam is irradiated with the fluorescent film 114.
By the excitation / emission caused by collision with the NTS
The television display can be performed according to the C system television signal.

The above-described structure is a schematic structure necessary for obtaining the image forming apparatus of the present invention used for display or the like, and the detailed parts such as the material of each member are limited to the above contents. However, it is appropriately selected so as to suit the purpose of the image forming apparatus. Further, although the NTSC system has been mentioned as the input signal, the image forming apparatus of the present invention is not limited to this, and other systems such as PAL and SECAM systems may be used, and more scanning lines than these may be used. A TV signal, for example, a high-definition TV system such as a MUSE system may be used.

Next, an example of the above-mentioned ladder-type electron source and the image forming apparatus of the present invention constructed by using the electron source will be described with reference to FIGS. 12 and 13.

In FIG. 12, 1 is a substrate, 104 is a surface conduction electron-emitting device, and 304 is a common wiring for connecting the surface conduction electron-emitting device 104. Ten common wirings are provided, each having external terminals D1 to D10. are doing.

The surface conduction electron-emitting device 104 is the substrate 1
A plurality of them are arranged in parallel on the top. This is called an element row. These element rows are arranged in a plurality of rows to constitute an electron source.

Each element row can be independently driven by applying an appropriate drive voltage between the common wiring 304 of each element row (for example, the common wiring 304 of the external terminals D1 and D2). That is, a voltage exceeding the threshold voltage may be applied to the element row where the electron beam is desired to be emitted, and a voltage lower than the threshold voltage may be applied to the element row where the electron beam is not desired to be emitted. The application of such a drive voltage applies to the common wirings D2 to D9 located between the element rows, the common wirings 304 adjacent to each other, that is, the external terminals D2 and D3, D4 and D5, D6 and D7 and D8 adjacent to each other. The common wiring 304 of D9 and D9 may be integrated into the same wiring.

FIG. 13 is a diagram showing the structure of a display panel 301 having the above-mentioned ladder-type electron sources.

In FIG. 13, 302 is a grid electrode, 303 is an opening through which electrons pass, D1 to Dm are external terminals for applying a voltage to each surface conduction electron-emitting device, and G1 to G1.
Gn is an external terminal connected to the grid electrode 302. Further, the common wiring 304 between each element row is formed on the substrate 1 as an integral same wiring.

Note that, in FIG. 13, the same reference numerals as those in FIG. 9 indicate the same members, and a big difference from the display panel 201 using the electron source of the simple matrix arrangement shown in FIG. The point is that the grid electrode 302 is provided between 116.

The grid electrode 302 is provided between the substrate 1 and the face plate 116 as described above. The grid electrode 302 is capable of modulating the electron beam emitted from the surface conduction electron-emitting device 104, and the electron beam is applied to the stripe-shaped electrode provided orthogonal to the device row in the ladder-type arrangement. To pass
A circular opening 303 is provided for each of the surface conduction electron-emitting devices 104.

The shape and position of the grid electrode 302 are
It does not necessarily have to be as shown in FIG. 13, and a large number of openings 303 may be provided in a mesh shape, and the grid electrode 302 may be provided, for example, around or near the surface conduction electron-emitting device 104. Good.

The external terminals D1 to Dm and G1 to Gn are connected to a drive circuit (not shown). Then, by applying a modulation signal for one image line to the column of the grid electrode 302 in synchronization with sequentially driving (scanning) the element rows one by one, each electron beam is irradiated on the fluorescent film 114. And images can be displayed line by line.

As described above, the image forming apparatus of the present invention is
It can be obtained by using any of the electron sources of the present invention in a simple matrix arrangement or a trapezoidal arrangement, and is suitable not only for the above-described television broadcast display device, but also as a video conference system and a display device such as a computer. A device is obtained. Furthermore, the present invention can be used as an exposure device of an optical printer including a photosensitive drum.

[0136]

EXAMPLES The present invention will be described in detail below with reference to specific examples, but the present invention is not limited to these examples, and each is within a range in which the object of the present invention is achieved. It also includes elements that have undergone element replacement or design changes.

Example 1 The structure of the surface conduction electron-emitting device of this example is the same as that shown in FIG. 1, and its manufacturing method will be described below based on the manufacturing process chart of FIG.

Step-1 A quartz substrate was used as the insulating substrate 1, and after sufficiently washing it with an organic solvent, electrodes 4 and 5 were formed on the surface of the substrate 1 (FIG. 4 (a)). In addition, Ni metal was used as the material of the electrodes, the electrode interval L was 4 μm, and the film thickness t ₂ was 1000 Å.

Step-2 Next, the organic Pd (C
After applying CP4230 / Okuno Pharmaceutical Co., Ltd., 30
A fine particle film 3 made of palladium oxide (PdO) fine particles (average particle diameter φ = 70Å) was formed by heating and baking at 0 ° C. (FIG. 4B). The thickness t ₁ of the fine particle film 3 is 300
Å The sheet resistance value was 2 × 10 ⁴ Ω / □.

As described above, the device of this embodiment has t ₁
(300Å) ≦ t ₂ (1000Å), and t ₂ (10
00Å) ≧ φ (70Å).

Step-3 Next, the substrate 1 is placed in the vacuum container 55 of the measurement / evaluation system shown in FIG.
Installed and evacuated with a vacuum pump to 2 × 10 ^-5 torr
After reaching the vacuum degree of (1), a voltage was applied from the power supply 51 between the device electrodes 4 and 5, and an energization process (forming process) was performed to form the electron emitting portion 2 (FIG. 4C). The voltage waveform of the forming process was in accordance with FIG. In this embodiment, the pulse width T1 is set to 1 msec, the pulse interval T2 is set to 10 msec, a rectangular wave is used instead of a triangular wave, and the peak value (peak voltage) of the rectangular wave is increased in 0.1 V steps to perform the forming process. went.

During the forming process, 0.1 is simultaneously applied.
A resistance measurement pulse was inserted between T2 at a voltage of V to measure resistance. The forming process was ended when the measured value by the resistance measurement pulse became about 1 M ohm or more, and at the same time, the application of the voltage to the element was ended.

Step-4 Subsequently, each of the elements subjected to the energization forming treatment was activated so that the crest value of the rectangular wave was 14 V with the waveform shown in FIG. 5B. Specifically, while measuring the device current If and the emission current Ie in the vacuum container 55, the device electrodes 4,
A pulse voltage was applied for 5 times. The vacuum container 55
The degree of vacuum inside was 1.5 × 10 ⁻⁵ torr, and the activation treatment was completed in about 30 minutes.

Step-5 Subsequently, after evacuating the inside of the vacuum container 55 to 10 ^-7 torr,
A stabilization process of baking at 180 ° C. for 5 hours was performed.

Next, the measurement of the electron emission characteristics of the surface conduction electron-emitting device manufactured by the above steps was carried out by the above-mentioned FIG.
The measurement evaluation system was used. Specifically, the distance between the anode electrode 54 and the electron-emitting device is 4 mm, the potential of the anode electrode 54 is 1 kV, and the degree of vacuum in the vacuum container 55 at the time of measuring the electron-emitting characteristics is 1 × 10 ⁻⁷ torr. A device voltage of 14 V was applied between 4 and 5, and a device current If and an emission current Ie flowing at that time were measured.

As a result, the device of this example was an electron-emitting device with stable device current If and emission current Ie and high efficiency from the initial measurement.

Example 2 In this example, a tin oxide (SnO ₂ ) dispersion liquid (SnO ₂ : 1 g,
MEK / cyclohexanone = 3/1 solvent: 1000c
c, butyral: 1 g) was used, and an electron-emitting device having the form shown in FIG. 1 was produced in the same manner as in Example 1.

The electrode spacing L of the electron-emitting device of this example is 1
0 μm, the film thickness t ₂ is 1 μm, and the film thickness t of the fine particle film 3 is
₁ is 1000Å, sheet resistance is 10 ⁴ to 10 ⁸ Ω /
□, the average particle diameter φ of the fine particles is 500Å.

As described above, the device of this embodiment has t ₁
(1000Å) ≦ t ₂ (1.0 μm), and t ₂
(1.0 μm) ≧ φ (500 Å).

When the characteristics of the above-mentioned device were measured in the same manner as in Example 1, good results were obtained as in the case of the device of Example 1.

Example 3 This example is the same as Example 1 except that the fine particle film 3 made of indium oxide (In ₂ O ₃ ) fine particles was formed by the gas deposition method, and shown in FIG. A morphological electron-emitting device was produced.

The electrode spacing L of the electron-emitting device of this example is 4
μm, the film thickness t ₂ is 1000 Å, the film thickness t ₁ of the fine particle film 3 is 350 Å, and the sheet resistance value is 10 ³ to 10 ⁷ Ω /
□, the average particle diameter φ of the fine particles is 350Å.

As described above, the device of this embodiment has t ₁
(350Å) ≦ t ₂ (1000Å), and t ₂ (10
00 Å) ≧ φ (350 Å).

When the characteristics of the above element were measured in the same manner as in Example 1, good results were obtained as in the case of the element in Example 1.

(Embodiment 4) A plan view of the electron-emitting device of this embodiment is shown in FIG. 2 (a), and a sectional view thereof is shown in FIG. 2 (b).

In this example, the electron-emitting device was similar to Example 1 except that the end faces of the electrodes 4 and 5 were tapered, the electrode interval L was 1 μm, and the film thickness t ₂ of the electrodes was 10 μm. Was produced.

Also in the device of this example, t ₁ (300Å) ≦ t
₂ (10 μm), and t ₂ (10 μm) ≧ φ (70
Å).

When the characteristics of the above element were measured in the same manner as in Example 1, good results were obtained as in the case of the element of Example 1.

(Embodiment 5) A plan view of the electron-emitting device of this embodiment is shown in FIG. 3 (a), and a sectional view thereof is shown in FIG. 3 (b).

In this embodiment, the film thickness of the electrodes 4 and 5 is set to 200.
An electron-emitting device was produced in the same manner as in Example 1 except that the thickness was set to 0 Å and the substrate was flattened so as to be flush with the substrate 1.

In this embodiment, there is substantially no film thickness difference between the electrodes 4 and 5, but the contact resistance between the electrodes 4 and 5 and the fine particle film 3 is substantially higher than the sheet resistance of the fine particle film 3. Since it was small, the same operation as in Example 1 was performed.

(Example 6) A plurality of electron-emitting devices of Examples 1 to 5 were linearly arranged to prepare an electron source as shown in FIG. 14, the same reference numerals as those in FIGS. 1 to 4 denote the same members.

G _{1 to} G _L 302 are modulating means (grid electrodes), and 303 is an opening. The distance between the substrate 1 and the modulation means 302 was 10 μm.

This electron source is placed in the measuring device of FIG.
At a vacuum degree of 10 −6 torr, between the device electrodes 4 and 5,
First, a driving voltage of 14V was applied, and then a voltage of 30V was applied to the modulation means 302 according to the information signal. As a result, electron beams were emitted from the plurality of electron emitters 2 according to the information signal.

In the electron source of this example, the variation of the electron beam emitted from each element by the above driving was extremely small, and each element had uniform characteristics.

(Embodiment 7) As shown in FIG. 15, an electron source was prepared in which a plurality of linear electron-emitting devices in which the electron-emitting devices of Examples 1 to 5 were linearly arranged were provided. 15, the same reference numerals as those in FIG. 14 indicate the same members.

The distance between the substrate 1 and the modulation means 302 is 10 μm.
m, and the spacing between the respective line-emission devices was 1 mm.

This electron source is placed in the measuring device of FIG.
At a vacuum degree of 10 −6 torr, between the device electrodes 4 and 5,
First, a drive voltage of 14 V was applied, and then a voltage according to the information signal was applied to the modulation means 302 according to the information signal. That is, the electron beam could be off-controlled at 0 V or less, and on-controlled at +30 V or more. Further, the electron amount of the electron beam could be continuously changed between 30 and 0V. As a result, the device electrodes 4, 5
Emission of an electron beam corresponding to the information signal for one line was obtained from the plurality of electron emission units 2 in between. By sequentially performing the above-described operation on the adjacent line electron-emitting devices, the electron beam emission according to all the information signals was obtained.

Also in this example, the same operational effects as in Example 6 could be confirmed.

Example 8 As shown in FIG. 16, an electron source similar to that of Example 7 was prepared except that the modulation means (grid electrode) 302 was provided on the surface of the substrate 1. This electron source was driven in the same manner as in Example 7, and an electron beam was emitted according to the information signal. However, in this electron source, the voltage applied to the modulation means 302 is -30 V.
The electron beam could be turned off below, and turned on at +20 V or higher. Further, the electron amount of the electron beam could be continuously changed between −30 and + 20V.

Also in this example, the same effect as in Example 7 could be confirmed.

(Embodiment 9) As shown in FIG. 17, except that the modulation means (grid electrode) 302 is arranged on the opposite side of the electron emission surface of the linear electron emission device via the substrate 1. An electron source similar to that in Example 7 was prepared. This electron source was driven in the same manner as in Example 7, and an electron beam was emitted according to the information signal. However, in the present electron source, the electron beam could be off-controlled at -30 V or less as the voltage applied to the modulation means 302, and could be on-controlled at +20 V or more. Further, the electron amount of the electron beam could be continuously changed between −30 and + 20V.

Also in this example, the same operational effects as in Example 7 could be confirmed.

(Embodiment 10) FIG. 18 is a schematic configuration diagram of an electron source of this embodiment. The present embodiment is an electron source having a simple matrix configuration in which a plurality of electron-emitting devices according to any of the first to fifth embodiments are arranged in rows and columns and each element is connected by a signal wiring electrode 12 and a scanning wiring electrode 13.

The driving method of this embodiment will be described. In order to emit an electron beam, each device voltage shown in Examples 1 to 5 was applied to the electron emitting device. First, 0V or 7V (a voltage pulse having a value half the device voltage) is applied to the plurality of electron-emitting devices on one line by the scanning wiring electrode 13, and then, in response to the information signal. 7 for the signal wiring electrode 12
By applying V (half the value of the element voltage) or 14 V (voltage pulse of the element voltage value), electron beam emission corresponding to the information signal for one line was obtained. By sequentially performing such an operation on a line adjacent to the above line, electrons for one screen are emitted.

Also in this example, the same operational effect as in Example 7 could be confirmed.

(Embodiment 11) An image forming apparatus shown in FIG. 19 was produced using the electron source of Embodiment 7. In the figure,
111 is a rear plate, 112 is a support frame, 113 is a glass substrate, 114 is a phosphor, 115 is a metal back, 11
6 is a face plate and 118 is an envelope. The distance between the face plate 116 and the rear plate 111 is 3 m
m.

This image forming apparatus was driven by the following method. A vacuum degree of 10 is set inside the envelope 118 which is composed of the face plate 116, the support frame 112 and the rear plate 111.
-6 torr of the voltage on the phosphor surface of the EV terminal 12
The voltage was set to 5 to 10 kV through No. 3, and a drive voltage of 14 V was first applied to the pair of device electrodes 4 and 5 through the wirings 20 and 21. Next, the wiring 2 is connected to the modulation means corresponding to the information signal.
By applying a voltage through No. 2, on-off of the emitted electron beam was controlled. Here, the electron beam could be off controlled at −30 V or less, and on controlled at 0 V or more. Also, -30
The electron quantity of the electron beam could be continuously changed between 0 V and gray scale display was possible.

The electron beam corresponding to the information signal emitted by the modulating means collides with the phosphor 114, and the phosphor 114
Displayed one line according to the information signal. One screen can be displayed by sequentially performing the above operation on the adjacent line electron-emitting devices.

The display image obtained by the image forming apparatus of the present example was a screen with high brightness and uniform brightness, little uneven brightness, and high contrast. In addition, the phosphor 114
As R (red), G (green), B (blue)
Face plate 1 of cathode ray tube, which is commonly used by using the three primary color phosphors
Even in the image forming apparatus of No. 16, the display image was a high-contrast and clear color image with little uneven brightness.

Example 12 The image forming apparatus shown in FIG. 20 was produced using the electron source of Example 8. Driving was performed in the same manner as in Example 11 to display the emission image of the phosphor 114. However, as the voltage applied to the modulating means, the electron beam was controlled to be off at -40 V or less, and the electron beam was controlled to be turned on at +10 V or more. Further, the electron amount of the electron beam can be continuously changed between -40 and +10 V, and gradation display was possible.

Also in this example, the same effect as in Example 11 could be confirmed.

Example 13 The image forming apparatus shown in FIG. 21 was produced using the electron source of Example 9. Driving was performed in the same manner as in Example 11 to display the emission image of the phosphor 114. However, as the voltage applied to the modulating means, the electron beam was controlled to be off at -40 V or less, and the electron beam was controlled to be turned on at +10 V or more. Further, the electron amount of the electron beam can be continuously changed between -40 and +10 V, and gradation display was possible.

Also in this example, the same effect as in Example 11 could be confirmed.

(Example 14) An image forming apparatus similar to that of Example 11 was prepared by using the electron source of Example 10 in the image forming apparatus shown in FIG. In the figure, reference numerals 12 and 13 denote wirings connected to the signal wiring electrodes and the scanning wiring electrodes, respectively.

The image forming apparatus of this example was driven by the following method. The inside of the envelope 118 composed of the face plate 116, the support frame 112, and the rear plate 111 is set to a vacuum degree of 10 −6 torr, and the voltage of the phosphor surface is EV.
It was set to 5 to 10 kV through the terminal 123, and in order to emit the electron beam, each element voltage shown in Examples 1 to 5 should be applied to the electron emitting element. First, with respect to a plurality of electron-emitting devices on one line, the scanning wiring electrode 13
A voltage pulse of 0 V or 7 V (half the value of the element voltage) is applied, and then the signal wiring electrode 1 corresponding to the information signal is applied.
2 to 7V (half the element voltage) or 14V
By applying the (voltage pulse of the element voltage value), the electron beam corresponding to the information signal for one line collided with the phosphor 114, and the phosphor 114 displayed for one line corresponding to the information signal. By sequentially performing such an operation on the line next to the above line, one screen can be displayed.

Also in this example, the same operational effects as in Example 11 could be confirmed.

(Embodiment 15) FIG. 23 shows a display panel using the above-mentioned electron-emitting device as an electron source so that image information provided from various image information sources including, for example, television broadcasting can be displayed. FIG. 3 is a diagram showing an example of the image forming apparatus of the present invention configured as described above.

In the figure, 16100 is a display panel and 1
Reference numeral 6101 denotes a display panel drive circuit, and 16102.
Is a display controller, 16103 is a multiplexer, 16104 is a decoder, 16105 is an input / output interface circuit, 16106 is a CPU, 16107 is an image generation circuit, 16108, 16109 and 1611.
0 is an image memory interface circuit, 16111 is an image input interface circuit, 16112 and 161.
Reference numeral 13 is a TV signal receiving circuit, and 16114 is an input unit.

When receiving a signal containing both video information and audio information, such as a television signal, the present image forming apparatus naturally reproduces audio at the same time as displaying video. Descriptions of circuits, speakers, and the like relating to reception, separation, reproduction, processing, storage, and the like of audio information that are not directly related to the features of the present invention will be omitted.

The functions of the respective parts will be described below along the flow of image signals.

First, the TV signal receiving circuit 16113 is a circuit for receiving a TV signal transmitted using a wireless transmission system such as radio waves or spatial optical communication.

The TV signal system to be received is not particularly limited. For example, NTSC system, PAL system, SEC.
Any method such as AM method may be used. Further, a TV signal comprising a larger number of scanning lines than these, for example, a so-called high-definition TV including the MUSE system is a signal suitable for taking advantage of the display panel suitable for a large area and a large number of pixels. Source.

The TV signal received by the TV signal receiving circuit 16113 is output to the decoder 16104.

The TV signal receiving circuit 16112 is a circuit for receiving a TV signal transmitted using a wired transmission system such as a coaxial cable or an optical fiber. A TV for receiving, similar to the TV signal receiving circuit 16113.
The signal system is not particularly limited, and the TV signal received by this circuit is also output to the decoder 16104.

Image input interface circuit 16111
Is a circuit for capturing an image signal supplied from an image input device such as a TV camera or an image reading scanner, and the captured image signal is output to the decoder 16104.

Image memory interface circuit 161
10 is a video tape recorder (hereinafter abbreviated as VTR)
The circuit for fetching the image signal stored in is output to the decoder 16104.

Image memory interface circuit 161
Reference numeral 09 denotes a circuit for capturing the image signal stored in the video disc, and the captured image signal is output to the decoder 16104.

Image memory interface circuit 161
Reference numeral 08 denotes a circuit for taking in an image signal from a device that stores still image data, such as a still image disc,
The captured still image data is input to the decoder 16104.

Input / output interface circuit 16105
Is a circuit for connecting the present display device to an external computer or an output device such as a computer network or a printer. It is of course possible to input / output image data and character / graphic information, and in some cases, input / output control signals and numerical data between the CPU 16106 of the image forming apparatus and the outside. .

The image generation circuit 16107 is used to input image data, character / graphic information, or the CPU 1 from the outside via the input / output interface circuit 16105.
6106 is a circuit for generating display image data based on image data and character / graphic information output from the 6106. Inside this circuit, for example, a rewritable memory for storing image data and character / graphic information, a read-only memory storing an image pattern corresponding to a character code, a processor for performing image processing, etc. And other circuits necessary for generating an image.

The display image data generated by this circuit is output to the decoder 16104, but in some cases, it can be output to an external computer network or printer via the input / output interface circuit 16105.

The CPU 16106 mainly performs operations related to operation control of the display device and generation, selection and editing of a display image.

For example, a control signal is output to the multiplexer 16103 to appropriately select or combine image signals to be displayed on the display panel. In that case, a control signal is generated to the display panel controller 16102 according to the image signal to be displayed, and the display frequency of the display device, the scanning method (for example, interlaced or non-interlaced), the number of scanning lines in one screen, and the like of the display device. The operation is controlled appropriately. In addition, the image data or the character / graphic information is directly output to the image generation circuit 16107, or the external computer or memory is accessed through the input / output interface circuit 16105 to display the image data or the character / graphic information. input.

It should be noted that the CPU 16106 may be involved in work for purposes other than this. For example, it may directly relate to a function of generating and processing information, such as a personal computer or a word processor. Alternatively, as described above, the input / output interface circuit 161
It is also possible to connect to an external computer network via 05 and collaborate with an external device for work such as numerical calculation.

The input unit 16114 is the CPU 1610.
6 is for the user to input commands, programs, data, etc., and various input devices such as a joystick, a bar code reader, a voice recognition device, etc. can be used in addition to the keyboard and mouse. .

The decoder 16104 is a circuit for inversely converting various image signals input from the above 16107 to 16113 into three primary color signals, or luminance signals and I signals and Q signals. It is desirable that the decoder 16104 has an image memory therein, as indicated by a dotted line in the figure. This is for handling a television signal that requires an image memory when performing inverse conversion, such as the MUSE method.

The provision of the image memory makes it easy to display a still image. Alternatively, the image generation circuit 1610
7 and the CPU 16106, there is an advantage that image processing and editing such as image thinning, interpolation, enlargement, reduction, and composition are facilitated.

The multiplexer 16103 is the CPU
The display image is appropriately selected based on the control signal input from the 16106. That is, the multiplexer 16
103 selects a desired image signal from the inversely converted image signals input from the decoder 16104 and outputs it to the drive circuit 16101. In that case, by switching and selecting an image signal within one screen display time, it is also possible to divide one screen into a plurality of areas and display different images depending on the areas, as in a so-called multi-screen television. .

Display panel controller 1610
Reference numeral 2 is a circuit for controlling the operation of the drive circuit 16101 based on the control signal input from the CPU 16106.

As a signal related to the basic operation of the display panel, for example, a signal for controlling an operation sequence of a power source (not shown) for driving the display panel is output to the drive circuit 16101. As a signal relating to the display panel driving method, for example, a signal for controlling a screen display frequency and a scanning method (for example, interlaced or non-interlaced) is supplied to the driving circuit 16101.
Output to Further, in some cases, a control signal relating to image quality adjustment such as luminance, contrast, color tone, and sharpness of a display image may be output to the driver circuit 16101.

The drive circuit 16101 is a circuit for generating a drive signal to be applied to the display panel 16100, and the image signal input from the multiplexer 16103 and the display panel controller 16 are provided.
The operation is based on a control signal input from 102.

Although the functions of the respective parts have been described above, the image information input from various image information sources can be displayed on the display panel 16100 in the image forming apparatus with the configuration illustrated in FIG. . That is, various image signals such as television broadcast are inversely converted by the decoder 16104 and then the multiplexer 16
It is appropriately selected in 103 and input to the driving circuit 16101. On the other hand, the display controller 16102
Generates a control signal for controlling the operation of the drive circuit 16101 according to the image signal to be displayed. Drive circuit 16
Reference numeral 101 applies a drive signal to the display panel 16100 based on the image signal and the control signal. As a result, the image is displayed on the display panel 16100. These series of operations are controlled by the CPU 16106 as a whole.

In this image forming apparatus, the image memory built in the decoder 16104 and the image generation circuit 16 are provided.
In addition to displaying the selected information from 107 and the information, the image information to be displayed may be enlarged or reduced, for example.
Image processing such as rotation, movement, edge enhancement, thinning, interpolation, color conversion, image aspect ratio conversion, combining, erasing,
It is also possible to perform image editing such as connection, replacement, and fitting. Although not specifically mentioned in the description of the present embodiment, a dedicated circuit for processing and editing audio information may be provided as in the above-described image processing and image editing.

Therefore, the present image forming apparatus includes a display device for television broadcasting, a terminal device for a video conference, an image editing device for handling still images and moving images, a terminal device for a computer,
It is possible to combine the functions of office terminals such as word processors, game machines, etc., with a very wide range of applications for industrial or consumer use.

Note that FIG. 23 merely shows an example of the configuration in the case of an image forming apparatus using a display panel having a surface conduction electron-emitting device as an electron beam source, and the image forming apparatus of the present invention is It goes without saying that the present invention is not limited to this.

For example, among the components shown in FIG. 23, circuits relating to functions unnecessary for the purpose of use may be omitted.
Conversely, additional components may be added depending on the purpose of use. For example, when this display device is applied as a video phone, a TV camera, a voice microphone,
It is preferable to add an illuminator, a transmission / reception circuit including a modem, and the like to the components.

In this image forming apparatus, since the surface conduction electron-emitting device is used as the electron source, the display panel can be easily thinned and the depth of the image forming apparatus can be reduced. In addition, a display panel using a surface conduction electron-emitting device as an electron beam source is easy to enlarge the screen, has high brightness, and has excellent viewing angle characteristics, so that the image forming apparatus is full of a sense of reality and has a powerful image. Can be displayed with good visibility.

[0219]

As described above, the electron-emitting device and the electron source of the present invention are extremely uniform without deterioration of the electron-emitting portion during fabrication, and have excellent electron-emitting characteristics. Further, in the electron source of the present invention, the variation in the electron emission characteristics among the elements (or between the electron emitting portions) is extremely small. Furthermore, when the electron source of the present invention is used, a high-contrast and clear image faithful to an information signal can be obtained, and particularly when a phosphor is used as an image forming member, the emission distribution of each bright spot of the emission image is uniform. In addition, an image forming apparatus having extremely small unevenness of bright spots and extremely little display flicker can be obtained.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment example of an electron-emitting device of the present invention.

FIG. 2 is a schematic configuration diagram showing an embodiment example of an electron-emitting device of the present invention.

FIG. 3 is a schematic configuration diagram showing an embodiment example of an electron-emitting device of the present invention.

FIG. 4 is a diagram for explaining a manufacturing process of the electron-emitting device of the present invention.

FIG. 5 is a diagram illustrating an example of a forming waveform.

FIG. 6 is a schematic configuration diagram illustrating an example of a measurement evaluation system for an electron-emitting device according to the present invention.

FIG. 7 is a diagram showing electrical characteristics of the surface conduction electron-emitting device of the present invention.

FIG. 8 is a schematic configuration diagram of the electron source of the present invention in a simple matrix arrangement.

FIG. 9 is a schematic configuration diagram of an image forming apparatus of the present invention using an electron source having a simple matrix arrangement.

FIG. 10 is a diagram illustrating a fluorescent film in the display panel of FIG. 9;

11 is a diagram illustrating an example of a drive circuit that drives the display panel of FIG.

FIG. 12 is a schematic plan view of a trapezoidal arrangement of electron sources.

FIG. 13 is a schematic configuration diagram of an image forming apparatus of the present invention using a trapezoidal arrangement of electron sources.

FIG. 14 is a schematic configuration diagram showing an electron source in Example 6.

FIG. 15 is a schematic configuration diagram showing an electron source in Example 7.

16 is a schematic configuration diagram showing an electron source in Example 8. FIG.

FIG. 17 is a schematic configuration diagram showing an electron source in Example 9.

FIG. 18 is a schematic configuration diagram showing an electron source in Example 10.

FIG. 19 is a schematic configuration diagram illustrating an image forming apparatus according to an eleventh embodiment.

FIG. 20 is a schematic configuration diagram illustrating an image forming apparatus according to a twelfth embodiment.

FIG. 21 is a schematic configuration diagram illustrating an image forming apparatus according to a thirteenth embodiment.

FIG. 22 is a schematic configuration diagram illustrating an image forming apparatus according to a fourteenth embodiment.

FIG. 23 is a block diagram illustrating an image forming apparatus according to a fifteenth embodiment.

FIG. 24 is a schematic view showing a conventional surface conduction electron-emitting device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate 2 Electron emission part 3 Conductive film 4,5 Element electrode 6 Concavo-convex part 12 Signal wiring electrode 13 Scan wiring electrode 50 Ammeter for measuring element current If 51 Power supply 52 Ammeter for measuring emission current Ie 53 high-voltage power supply 54 anode electrode 55 vacuum device 56 exhaust pump 57 gas introduction pipe 102 X-direction wiring (lower wiring) 103 Y-direction wiring (upper wiring) 104 surface conduction electron-emitting device 105 connection 111 rear plate 112 support frame 113 glass substrate 114 Fluorescent Film 115 Metal Back 116 Face Plate 118 Envelope 121 Black Conductive Material 122 Phosphor 123 EV Terminal 201 Display Panel 202 Scanning Circuit 203 Control Circuit 204 Shift Register 205 Line Memory 206 Sync Signal Separation Circuit 207 Modulation Signal Generator 301 Display panel 02 grid electrode 303 aperture 304 common wiring 16100 display panel 16101 drive circuit 16102 display controller 16103 multiplexer 16104 decoder 16105 input / output interface circuit 16106 CPU 16107 image generation circuit 16108 image memory interface circuit 16109 image memory interface circuit 16110 image memory interface circuit 16111 image input Interface circuit 16112 TV signal receiving circuit 16113 TV signal receiving circuit 16114 Input unit

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Shinichi Kawate 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Ichiro Nomura 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Kazuhiro Michi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (11)

[Claims] 1. An electron-emitting device having a conductive film having an electron-emitting portion formed between electrodes, wherein the conductive film is composed of a fine particle film, and the thickness t of the fine particle film is t.
₁ and the thickness t _{2 of the} electrode satisfy the relationship of t ₁ ≦ t ₂ and the average particle diameter φ of the fine particles constituting the fine particle film satisfies the relationship of t ₂ ≧ φ. Electron emitting device. 2. The electron-emitting device according to claim 1, wherein the contact resistance between the fine particle film and the electrode and the sheet resistance of the fine particle film satisfy the relationship of contact resistance <sheet resistance. 3. The sheet resistance of the fine particle film is from 10 ³ to
The electron-emitting device according to claim 1 or 2, wherein the electron emission device has a range of 10 ¹⁰ Ω / □. 4. The electron emitting device according to claim 1, wherein the electron emitting device is a surface conduction electron emitting device. 5. An electron source comprising the electron-emitting device according to claim 1 and a driving unit for driving the electron-emitting device. 6. The electron source according to claim 5, wherein the electron source is an electron source having at least one row of elements in which a plurality of electron-emitting devices are connected in parallel. 7. The electron source according to claim 5, wherein the electron source is an electron source in which a plurality of element rows in which a plurality of electron emitting elements are connected are arranged in a matrix. 8. The electron-emitting device according to claim 1, an image forming member, and irradiation of an electron beam emitted from the electron-emitting device to the image forming member according to an information signal. An image forming apparatus comprising: a driving unit that controls the image forming apparatus. 9. The image forming apparatus according to claim 8, wherein the image forming apparatus is an image forming apparatus having at least one element row in which a plurality of the electron-emitting devices are connected in parallel. . 10. The image forming apparatus according to claim 8, wherein the image forming apparatus is an image forming apparatus in which a plurality of element rows in which a plurality of the electron-emitting devices are connected are arranged in a matrix. apparatus. 11. The image forming apparatus according to claim 8, wherein the image forming member is a phosphor.