JPH08329866A - Image forming device - Google Patents

Abstract

(57) [Summary] [Object] To obtain a high-quality image forming apparatus in which the voltage drop caused by the wiring resistance between surface conduction electron-emitting devices is made constant and the electron beam amount is made uniform. A wiring resistance value between surface conduction electron-emitting devices is set to at least two different values.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus using an electron source in which a plurality of surface conduction electron-emitting devices are electrically connected.

[0002]

2. Description of the Related Art A surface conduction electron-emitting device utilizes a phenomenon in which electron emission occurs when a current is passed through a conductive thin film formed on an insulating substrate in parallel with the film surface.

As a typical example of the structure of the surface conduction electron-emitting device, a conductive thin 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 thin film, for example, 1
It is usually carried out by applying and energizing a rising voltage of about V / 1 minute to locally destroy, deform or alter the conductive thin film to change the structure and form an electron emitting portion in an electrically high resistance state. It is a process to do. The electron emission is performed from the vicinity of the crack generated in the electron emitting portion by applying a voltage to the conductive thin 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 by (also called common wiring) are arranged (also called a ladder arrangement) is disclosed (Japanese Patent Laid-Open Nos. 1-33132 and 1-2837).
No. 49, No. 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. 5,066,506).
883).

[0006]

By the way, when the surface conduction electron-emitting device is applied to an image forming apparatus, generally, a large number of surface conduction electron-emitting devices are arranged on a substrate,
Electrical wiring between each element with thin or thick film electrodes,
Although it was used as a multi-electron beam source, there is a phenomenon in which the voltage applied to each element varies due to a voltage drop caused by wiring resistance. As a result, the amount of current of the electron beam emitted from each surface conduction electron-emitting device varies, which causes a problem that density unevenness occurs in the formed image.

14 and 15 are views for explaining this problem in more detail. In both figures, (a) is an equivalent circuit diagram including a surface conduction electron-emitting device, a wiring resistance and a power source.
(B) is a figure which shows the electric potential of the positive electrode and negative electrode of each surface conduction electron-emitting device, (c) is a figure which shows the voltage applied between the positive and negative electrodes of each surface conduction electron-emitting device.

FIG. 14A shows a circuit in which _N surface-conduction electron-emitting devices D ₁ to DN connected in parallel are connected to a power supply V _E. The positive electrode of the power supply and the surface-conduction electron are shown. the positive electrode of the discharge device D _1, also is obtained by connecting the negative electrode and the negative electrode of the surface conduction electron-emitting devices D _N of the power supply. Further, the common wiring connecting the surface conduction electron-emitting devices in parallel has a resistance component of r between the adjacent surface conduction electron-emitting devices as shown in the figure (in the image forming apparatus, the Since the target pixels are normally arranged at equal pitches, the surface conduction electron-emitting devices are also arranged at equal intervals spatially, and the wiring connecting these may vary in width and film thickness due to manufacturing. Unless they have the same resistance between the surface conduction electron-emitting devices.

Further, the surface conduction electron-emitting devices D _{1 to} D _N
Have substantially equal resistance values Rd.

In the circuit of FIG. 14A, the potentials of the positive and negative electrodes of each surface conduction electron-emitting device are shown in FIG.
4 (b). The horizontal axis of the figure shows the element numbers D _{1 to DN} , and the vertical axis shows the potential. The ● mark represents the positive electrode potential of each surface conduction electron-emitting device, and the ■ mark represents the negative electrode potential, and the ● mark (■ mark) is connected by a solid line for convenience in order to make it easier to see the tendency of the potential distribution.

As is apparent from this figure, the voltage drop due to the wiring resistance r does not occur uniformly, and on the positive electrode side, it becomes steeper as it gets closer to the surface conduction electron-emitting device D1.
On the other hand, on the negative electrode side, the current flowing through the wiring resistance r is larger as it is closer to D _1, and on the negative electrode side, the larger current is flowing as it is closer to D _N.

FIG. 14 (c) shows the voltage applied between the negative electrodes of the surface conduction electron-emitting devices. The vertical axis represents the applied voltage, and the circles are connected by a solid line for the sake of convenience in order to make it easier to see the same tendency as in FIG.

As is apparent from this figure, in the case of the circuit as shown in FIG. 14A, the larger the voltage is applied to the surface conduction electron-emitting devices (D ₁ and D _N ) at both ends, the larger voltage is applied to the center. The applied voltage is small in the surface conduction electron-emitting device near the portion. Therefore, the electron beam emitted from each surface conduction electron-emitting device has a larger emission current as the surface conduction electron-emitting devices at both ends are applied, which is extremely inconvenient when applied to an image forming apparatus (for example, at both ends). The image in the near area has a high density, and the density in the vicinity of the center becomes light.)

On the other hand, FIG. 15 shows one side of a device array connected in parallel (in this figure, a surface conduction electron-emitting device D ₁
Side) is connected to the positive and negative electrodes of the power supply. In the case of such a circuit, the potential on the positive electrode side and the potential on the negative electrode side are shown in FIG.
It becomes as shown in (b).

Therefore, the voltage applied to each surface conduction electron-emitting device becomes larger as it approaches D ₁ as shown in FIG. 2C, which is extremely inconvenient for application as an image forming apparatus. .

The degree of variation in the applied voltage for each surface conduction electron-emitting device as shown in the above two examples depends on the total number N of surface conduction electron-emitting devices connected in parallel, the device resistance Rd and the wiring resistance r. Ratio (= Rd / r) or the connection position of the power source, but generally, the larger N is, the more R
The smaller d / r is, the more remarkable the variation is, and the connection method of FIG. 15 has a greater variation of the voltage applied to the surface conduction electron-emitting device than that of FIG.

For example, in the connection method of FIG.
= 1 kΩ, r = 10 mΩ, and N = 100,
Comparing the surface conduction electron-emitting device having the largest applied voltage and the surface conduction electron-emitting device having the smallest applied voltage, Vmax:
Vmin = 102: 100, but N = 1000
Then, Vmax: Vmin = 472: 100, and the ratio of variation becomes large.

Further, N = 1000, Rd = 1 kΩ, r =
In the case of 1 mΩ, Vmax: Vmin = 127: 10
Although it is about 0, in the case of a wiring resistance of r = 10 mΩ,
The degree of variation becomes large as Vmax: Vmin = 472: 100.

As described above, when a plurality of surface-conduction type electron-emitting devices having the same characteristics are connected in parallel, the voltage drop caused by the wiring resistance effectively applies the voltage to each surface-conduction type electron-emitting device. The generated voltage varies depending on the surface conduction electron-emitting device, and the emission amount of the electron beam becomes non-uniform, which is inconvenient when applied as an image forming apparatus.

In particular, when trying to realize a large-capacity display device having a large number of pixels (that is, a large N), the ratio of the above-mentioned variation becomes remarkable, and the uneven density of the image becomes a serious problem.

According to the present invention, the voltage drop caused by the wiring resistance between the surface conduction electron-emitting devices is made constant to reduce the variation in the voltage applied to each surface conduction electron-emitting device, so that each surface conduction electron An object of the present invention is to obtain an image forming apparatus capable of obtaining a high quality image by making the amount of electron beams emitted from the emitting element uniform.

[0022]

The image forming apparatus of the present invention uses an electron source in which a plurality of surface conduction electron-emitting devices each having a conductive thin film formed between device electrodes on a substrate are electrically connected. In the image forming apparatus described above, the wiring resistance value between the surface conduction electron-emitting devices is made different by at least two or more different values, and means for making the wiring resistance value different is a wiring width, It is made by changing the wiring thickness or the wiring composition.

More specifically, the positive electrode side extraction electrode of the plurality of surface conduction electron-emitting devices connected in parallel is arranged at one end of the positive electrode side electrode of the element array, and the negative electrode side extraction electrode is the other of the negative electrode side electrode of the element array. It is characterized in that the wiring resistance value between the surface conduction electron-emitting device elements is arranged at the end and increases as the distance from the extraction electrode increases.

Alternatively, the resistance value of the positive electrode side wiring connecting the i-th and (i + 1) th surface conduction electron-emitting devices from the side where the positive electrode side electrode is taken out is r _i , and the resistance value of the negative electrode side wiring is r ′ _Ni . When expressed, the resistance value is (N−i) r _i = (N
-I) satisfy the relation of _{r 'i = r Ni = r} ' Ni.

FIG. 1 is a diagram for explaining the image forming apparatus of the present invention in more detail. FIG. 1A is an equivalent circuit diagram including a surface conduction electron-emitting device, a wiring resistance and a power source, and FIG.
FIG. 3 is a diagram showing the potentials of the positive electrode and the negative electrode of each surface conduction electron-emitting device.

FIG. 1A shows a circuit in which _N surface-conduction electron-emitting devices D ₁ to DN connected in parallel are connected to a power supply V _E. The positive electrode of the power supply and the surface-conduction electron are shown. the positive electrode of the discharge device D _1, also is obtained by connecting the negative electrode and the negative electrode of the surface conduction electron-emitting devices D _N of the power supply.

Further, the surface conduction electron-emitting devices D _{1 to} D _N
Have substantially equal resistance values Rd.

In the present invention, the common wiring connecting the surface conduction electron-emitting devices in parallel is, as shown in FIG. 9A, between adjacent surface conduction electron-emitting devices D _i and D _{i + 1} . , R _{i on} the positive electrode side and r ′ _Ni on the negative electrode side, and r _N-1 = 2r _N-2 = ... Between these resistance components.
= (N-i) r _i = ... = (N-2) r ₂ = (N-1) r
_{1 = r 'N-1 =} 2r' N-2 = ... = (N-i) r 'i = ...
= (N-2) r ' ₂ = (N-1) r' ₁ holds.

If a current j flows through each surface conduction electron-emitting device at this time, the voltage drop ΔV _i between adjacent surface conduction electron-emitting devices D _i -D _{i + 1} is ΔV _i = ( N−i) jr _i = (N−i) j × r _i / (N−i) = jr _N−1 negative electrode, ΔV _i = ijr ′ _Ni = ij × r ′ _N−1 / {N− (N -I)} = ij × r ′ _N−1 / i = jr ′ _N−1 , and the voltage drop ΔV _i has a constant value regardless of the position of the surface conduction electron-emitting device.

FIG. 1 (b) shows this by the potentials of the positive electrode and the negative electrode of each surface conduction electron-emitting device. The horizontal axis of the figure shows the element numbers D _{1 to DN} , and the vertical axis shows the potential. ● indicates the positive electrode potential of each surface conduction electron-emitting device.
The mark represents the negative electrode potential, and in order to make it easy to see the tendency of the potential distribution, the solid circles (●) are connected for convenience. From this, the voltage applied between the positive and negative electrodes of each surface conduction electron-emitting device is plotted in FIG. 1 (c). The horizontal axis of the figure shows the element numbers D _{1 to DN} , and the vertical axis shows the voltage applied to the surface conduction electron-emitting device.

Further, the image forming apparatus of the present invention uses a surface conduction electron-emitting device as described below and an electron source in which a plurality of such devices are arranged.

There are two types of surface conduction electron-emitting devices, a planar type and a vertical type, and the basic structure of a planar type surface conduction electron-emitting device will be described.

FIGS. 2A and 2B are views showing the basic structure of a flat surface conduction electron-emitting device.

In FIG. 2, 1 is a substrate, 2 is an electron emitting portion,
Reference numeral 3 is a conductive thin film, and 4 and 5 are device electrodes.

The substrate 1 is, for example, quartz glass or Na.
Examples thereof include glass having a reduced content of impurities such as blue glass, soda lime glass, a laminated body obtained by laminating SiO ₂ on soda lime glass by a sputtering method, 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
A printed conductor composed of a metal or a metal oxide and glass, a transparent conductor such as In ₂ O ₃ —SnO ₂ and a semiconductor conductor material such as polysilicon are appropriately selected.

The element electrode interval L, the element electrode length W, the shape of the conductive thin 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, and 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 consideration of the electrode resistance and electron emission characteristics, and the device electrode thickness d is
Hundreds of Angstroms to a few micrometers.

In the surface conduction electron-emitting device shown in FIG. 1, the device electrodes 4, 5 and the conductive thin film 3 are laminated on the substrate 1 in this order. The conductive thin film 3 and the device electrodes 4 and 5 may be laminated in this order.

The conductive thin film 3 is particularly preferably a fine particle film composed of fine particles in order to obtain good electron emission characteristics. The thickness of the conductive thin film 3 depends on the step coverage of the device electrodes 4 and 5 and the device. It is appropriately selected depending on the resistance value between the electrodes 4 and 5 and the forming conditions described later. The conductive thin film 3 has a thickness of preferably several angstroms to several thousand angstroms, particularly preferably 10 angstroms to 500 angstroms, and its resistance value is 10 3 to 10 7 ohm / square sheet. It is the resistance value.

Examples of the material forming the conductive thin film 3 include Pd, Pt, Ru, Ag, Au, Ti, In and C.
Metals such as u, Cr, Fe, Zn, Sn, Ta, W and Pb, PdO, SnO ₂ , In ₂ O ₃ , PbO and Sb ₂ O
Oxides such as ₃ , HfB ₂ , ZrB ₂ , LaB ₆ , CeB
Boride such as ₆ , YB ₄ , GdB ₄ , TiC, ZrC, H
Carbides such as fC, TaC, SiC, WC, TiN, Z
Examples thereof include nitrides such as rN and HfN, semiconductors such as Si and Ge, and carbon.

The fine particle film is a film in which a plurality of fine particles are aggregated, and its fine structure is not only in a state where the fine particles are individually dispersed and arranged but also in a state where the fine particles are adjacent to each other or overlap each other (island shape). Including). In the case of a fine particle film, the particle diameter of the fine particles is preferably several angstroms to several thousand angstroms, and particularly preferably 10 angstroms to 200 angstroms.

A crack is included in the electron emitting portion 2, and the electron is emitted from the vicinity of this crack. The electron emitting portion 2 including the crack and the crack itself are formed depending on the film thickness of the conductive thin film 3, the film quality, the material, the forming conditions described later, and the like. Therefore, the position and shape of the electron emitting portion 2 are not limited to the position and shape as shown in FIG.

The crack may have conductive fine particles having a particle diameter of several angstroms to several hundred angstroms. The conductive fine particles are the same as some or all of the elements of the material forming the conductive thin film 3. Further, the electron emitting portion 2 including a crack and the conductive thin film 3 in the vicinity thereof may contain carbon and a carbon compound.

Next, the basic structure of the vertical type surface conduction electron-emitting device will be described.

FIG. 3 is a view showing a basic structure of a vertical type surface conduction electron-emitting device. In the figure, reference numeral 21 denotes a step forming member, and the same reference numerals as those in FIG. 1 denote the same members.

The substrate 1, the electron emitting portion 2, the conductive thin film 3 and the device electrodes 4 and 5 are made of the same material as that of the above-mentioned plane type surface conduction electron emitting device.

The step forming member 21 is formed by, for example, a vacuum vapor deposition method,
It is made of an insulating material such as SiO ₂ attached by a printing method, a sputtering method or the like. The film thickness of the step forming member 21 corresponds to the device electrode interval L (see FIG. 2) of the flat surface conduction electron-emitting device described above. It is set by the voltage applied between the first and second electrodes, but is preferably several hundred angstroms to several tens of micrometers, and particularly preferably several hundred angstroms to several micrometers.

Since the conductive thin film 3 is usually formed after the device electrodes 4, 5 are formed, it is laminated on the device electrodes 4, 5, but after the conductive thin film 3 is formed, the device electrodes 4, 5 are formed. It is also possible to make it so that the device electrodes 4 and 5 are laminated on the conductive thin film 3. Further, as described in the description of the planar type surface conduction electron-emitting device, the formation of the electron-emitting portion 2 depends on the film thickness of the conductive thin film 3, the film quality, the material, and the manufacturing method such as forming conditions described later. Therefore, the position and shape are not limited to the position and shape shown in FIG.

In the following description, of the above-mentioned planar type surface conduction electron-emitting device and vertical type surface conduction type electron emission device, the planar type is taken as an example. A vertical surface conduction electron-emitting device may be used instead of the electron-emitting device.

Various methods can be considered as a method of manufacturing the surface conduction electron-emitting device, and one example thereof will be described with reference to FIGS. 4 to 6. In FIG. 4, the same symbols as those in FIG. 2 indicate 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 a device is formed on the surface of the substrate 1 by a photolithography technique. The 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 device electrode 5 are connected to form an organometallic thin film.
The organic metal solution is a solution of an organic compound whose main element is a metal that is a constituent material of the conductive thin film 3 described above. Then, the organic metal thin film is heated and baked to form the conductive thin film 3 which is patterned by lift-off, etching or the like (FIG. 4B).

By controlling the heating temperature at a predetermined temperature during the above heating and firing, the constituent material of the conductive thin film 3 is either a two-phase mixed state of an oxide and a metal or an oxide having a non-stoichiometric composition. It is preferable to have it. This is because the resistance value can be adjusted over a wide range by re-oxidation or re-reduction.

Although the organic metal solution coating method has been described here, the present invention is not limited to this. For example, vacuum vapor deposition method, sputtering method, chemical vapor deposition method, dispersion coating method, dipping method, spinner method, etc. It is also possible to form an organic metal film.

3) Subsequently, an energization process called forming is performed. When electricity is applied between the device electrodes 4 and 5 from a power source (not shown), the electron emitting portion 2 having a changed structure is formed at the site of the conductive thin film 3 (FIG. 4C). By this energization treatment, the conductive thin film 3 is locally destroyed, deformed or altered, and the electron-emissive portion 2 is a portion whose structure is changed.

FIG. 5 shows an example of the voltage waveform of 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 pulse interval of the voltage waveform, for example, T1 is 1 microsecond to 10 milliseconds and T2 is 10 microseconds to 100.
It is set to millisecond, and the peak value (peak voltage during forming) is appropriately selected according to the form of the surface conduction electron-emitting device described above, and applied for several seconds to several tens of minutes in a vacuum atmosphere with an appropriate degree of vacuum. The voltage waveform to be applied is not limited to the illustrated triangular wave, and a desired waveform such as a rectangular wave can be used.

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.
Similar to (a), the crest value (peak voltage during forming) is increased by, for example, about 0.1 V step,
Application is performed in an appropriate vacuum atmosphere similar to the description of FIG.

During the pulse interval T2, a voltage that does not locally destroy, deform, or alter the conductive thin film 3,
For example, it is preferable to measure the device current at a voltage of about 0.1 V to obtain a resistance value, and terminate the forming when a resistance of, for example, 1 M ohm or more is exhibited.

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

6, the same reference numerals as those in FIG. 2 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 thin film 3 between the device electrodes 4 and 5, and 54 is an electron emitting portion 2. The anode electrode 53 for trapping the emission current Ie to be generated, 53 is a high voltage power source 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, and 57 is a gas inlet.

The surface conduction electron-emitting device, the anode electrode 54 and the like are installed in a vacuum device 55.
Is equipped with necessary equipment such as a vacuum gauge (not shown),
The surface conduction electron-emitting device can be measured and evaluated under a desired vacuum.

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 such as an ion pump.
The entire vacuum device 55 and the substrate 1 of the surface conduction electron-emitting device can be heated up to about 200 ° C. by a heater. 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) It is preferable to subject the surface conduction electron-emitting device thus produced to an activation step.

The activation process is, for example, 10 −4 to 1
It is a process of repeating the application of pulses with a pulse peak value of a constant voltage at a vacuum degree of 0 −5 torr.
By depositing carbon and carbon compounds in the electron emission portion 2 from an organic substance existing in a vacuum atmosphere, the device current and emission current can be significantly improved. It is effective to perform this activation step while measuring the device current and the emission current, for example, and to end it when the emission current is saturated, because it is effective. Also,
The pulse peak value in the activation step is preferably the peak value of the driving voltage.

The carbon and the carbon compound are graphite (both single crystal and polycrystal) and amorphous carbon (amorphous carbon and a mixture thereof with polycrystal graphite). The deposited film thickness is preferably 500 angstroms or less, more preferably 3 angstroms or less.
It is less than 00 angstrom.

5) Further, it is preferable to carry out a stabilizing step of operating and driving the surface conduction electron-emitting device 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 that 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 surface conduction electron-emitting device in the above-mentioned vacuum atmosphere, it becomes possible to suppress further deposition of carbon and carbon compounds, whereby the device current If and the emission current Ie can be suppressed. Is stable.

The basic characteristics of the surface conduction electron-emitting device thus obtained 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 in 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 It is based on the measurement performed as ~ 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 non-linear 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 emitted charges trapped in the anode electrode 54 (see FIG. 6) depend 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 characteristics of such a surface conduction electron-emitting device is the characteristics 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, the surface conduction electron-emitting device in which the device current If has a VCNR characteristic with respect to the device voltage Vf also has the above three characteristic features.

Next, an example of an electron source in which a plurality of surface conduction electron-emitting devices are arranged and an image forming apparatus of the present invention using the same will be described with reference to FIGS. 8 and 9.

In FIG. 8, 1 is a substrate, 104 is a surface conduction electron-emitting device, 304 is a surface conduction electron-emitting device 1.
There are 10 common wirings for connecting 04, each having external terminals D1 to D10.

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 array. A plurality of rows of the element columns are arranged to form an electron source.

Each element row can be independently driven by applying an appropriate drive voltage between the common wiring 304 of each element column (for example, the common wiring 304 of the external terminals D1 and D2). That is, a voltage higher than the threshold voltage may be applied to the element array in which the electron beam is desired to be emitted, and a voltage lower than the threshold voltage may be applied to the element array in which the electron beam is not desired to be emitted. The application of such a driving voltage is performed on the common wirings D2 to D9 located between the respective element columns by adjoining the common wirings 304 adjacent to each other, that is, the external terminals D2 and D3, D4 and D5, D6 and D7, respectively. The common wiring 304 for D8 and D9 can also be formed as an integrated single wiring.

FIG. 9 shows a display panel 3 provided with the above electron source.
It is a figure which shows the structure of 01.

In FIG. 9, 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 G.
n 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 integrated single wiring.

In FIG. 8, 111 is a rear plate and 1 is a rear plate.
Reference numeral 12 is a support frame, 116 is a face plate, and 118 is an envelope.

A grid electrode 302 is provided between the substrate 1 and the face plate 116. 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 a stripe-shaped electrode that is orthogonal to the ladder-shaped arrangement of the device rows. A circular opening 303 corresponding to each surface-conduction type electron-emitting device 104 is formed in order to allow passage.
Is provided.

The shape and position of the grid electrode 302 are
It does not necessarily have to be as shown in FIG. 9, 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 columns of the grid electrode 302 in synchronization with the sequential driving (scanning) of the element rows one column at a time, irradiation of each electron beam to the fluorescent film 114 is performed. The image can be displayed line by line.

As described above, the image forming apparatus of the present invention is
It is possible to obtain an image forming apparatus that can be obtained by using a trapezoidal arrangement of electron sources and is suitable not only for the above-mentioned display device for television broadcasting but also for a display device such as a video conference system and a computer. Further, it can also be used as an exposure device of an optical printer configured with a photosensitive drum.

[0094]

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

Example 1 FIG. 10 is a plan view of surface-conduction type electron-emitting devices connected in parallel used in the image forming apparatus of Example 1. FIG.
In 0, 1 is a substrate, 3 is a conductive thin film, 11 is a positive electrode, and 12 is a negative electrode.

₁₀₀₀ surface-conduction electron-emitting devices D _{1 to} D 1000 are formed, and the central portion is omitted in FIG. 10A. Further, FIG. 10B is an enlarged view of the element portion, where a is the distance between the element electrodes and b is the width of the conductive thin film 3.

First, the electrodes 11 and 12 are formed on the cleaned substrate 1 by the usual photolithography technique. The width of the wiring portion gradually decreases from the D ₁ side to the D ₁₀₀₀ side on the positive electrode side, and gradually decreases from the D ₁₀₀₀ side to the D ₁ side on the negative electrode side. The value is the wiring width W ₁ on the positive electrode side between D _{1 and} D _2.
Is 1 mm, the wiring width W ′ ₁ on the negative electrode side is 1 μm, and the wiring width W ₉₉₉ on the positive electrode side between D _{999 and} D ₁₀₀₀ is 1.
Micrometers, the negative-side wiring width W _'999 is 1 millimeter. Moreover, the distance a between the element electrodes of the element portion was set to 2 micrometers.

Next, organic Pd (ccp4230 manufactured by Okuno Chemical Industries Co., Ltd.) was spin-coated on the substrate 1 on which the electrodes 11 and 12 were formed by a spinner, and heated and baked at 250 ° C. for 10 minutes. Incidentally, the fine particle film described here is a film in which a plurality of fine particles are gathered as described above, 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. (Including islands), the particle size refers to the diameter of the fine particles whose particle shape can be recognized in this state.

Then, the thin film 3 after firing is patterned by using a normal photolithography technique so that the width b of the conductive thin film 3 becomes 300 μm, as shown in FIG. 10B. The electron emitting portion was formed.

Next, a glass spacer having a thickness of 5 mm was provided on the substrate 1, and a phosphor substrate in which a phosphor was uniformly applied was provided on the spacer 1, and then the whole was placed in the measurement and evaluation system shown in the figure. The electron emission characteristics were confirmed at an acceleration voltage of 1 kV while maintaining a vacuum degree of about 1 × 10 −6 torr. The connection method of the power supply, the positive electrode of the D ₁ side of the electrode 11, 12, D
_{The 1000} side was grounded.

As a result, bright spots corresponding to each emitting portion were observed, and the brightness of each bright spot was visually almost uniform. Also,
When the variation in each luminance was measured using a spot luminance meter, the variation was within 5%.

Example 2 FIG. 11 is a plan view of surface-conduction type electron-emitting devices connected in parallel used in the image forming apparatus of Example 2. FIG.
The same reference numerals as 0 indicate the same members.

₁₀₀₀ surface-conduction electron-emitting devices D _{1 to} D 1000 are formed, and the central portion is omitted in FIG. 11B is a sectional view of the wiring portion of the positive electrode, and FIG. 11C is a sectional view of the wiring portion of the negative electrode.

The positive electrode side electrode becomes gradually thinner from the D ₁ side to the D ₁₀₀₀ side, the thickness between D _{1 and} D ₂ is 100 μm, and the thickness between D _{999 and} D ₁₀₀₀ is 100 μm. Is 0.1 micrometer. On the other hand, the electrode on the negative electrode side is gradually thinner from the D ₁₀₀₀ side to the D ₁ side, and the thickness between D _{999 and} D ₁₀₀₀ is 100 μm, and the thickness between D _{1 and} D ₂ is 100 μm. It is 0.1 micrometer.

Next, the manufacturing procedure of the image forming apparatus of the second embodiment will be described.

First, the electrodes 11 and 12 are formed on the cleaned substrate 1 by the usual photolithography technique. At this time, the thickness of the electrodes 11 and 12 is 100 micrometers, and the distance a between the element electrodes of the element portion is 22.
It was set to micrometer.

Next, the thicknesses of the electrodes 11 and 12 are shown in FIG.
An etching process was performed in order to obtain the patterns shown in (b) and (c). First, the negative electrode 12 was protected by a resist film, and the positive electrode 11 was etched. At this time,
The thickness between D _{1000 and} D ₉₉₉ is 0.1 micrometer, D
The thickness of between ₁ -D ₂ to 100 micrometers, when immersing the substrate 1 in an etching solution, gradually soaked from D ₁₀₀₀ side, the etching time and D ₁₀₀₀ side and the D ₁ side The thickness of the electrode 11 was controlled by changing it.
Similarly, the positive electrode 11 is protected by a resist film,
The negative electrode 12 was etched. In this case, when the substrate 1 was dipped in the etching solution, it was gradually dipped from the D ₁ side.

Next, organic Pd (ccp4230 manufactured by Okuno Chemical Industries Co., Ltd.) was spin-coated by a spinner on the substrate 1 on which the electrodes 11 and 12 were formed, and heated and baked at 250 ° C. for 10 minutes.

Then, the thin film 3 after firing is patterned by using a normal photolithography technique so that the width b of the conductive thin film 3 becomes 300 μm, as shown in FIG. 10B. The electron emission part was formed.

On the thus obtained substrate 1, a phosphor substrate is provided via a glass spacer as shown in FIG. 9, and a grid electrode 302 as a modulating means is provided between them,
It is housed in the envelope 118, and the inside is 1 × 10 −6 to
The display panel 301 was created by evacuating to a vacuum degree of about rr. The power supply connection method is as follows. The electrodes 11 and 12 are driven at a power supply voltage of 15 V and an acceleration voltage of 1 kV with the D ₁ side being the positive electrode and the D ₁₀₀₀ side being the ground. As a result, bright spots corresponding to each emitting portion were observed, and the variation in the luminance was within 5%.

Example 3 FIG. 12 is a plan view of surface-conduction type electron-emitting devices connected in parallel used in the image forming apparatus of Example 3. FIG.
The same reference numerals as 0 indicate the same members.

₁₀₀₀ surface conduction electron-emitting devices D _{1 to} D 1000 are formed, and the central portion is omitted in FIG. The electrodes 11 and 12 are made of phosphorus-doped polycrystalline silicon, and the phosphorus concentration for changing the resistance value differs depending on the location.

Next, the manufacturing procedure of the image forming apparatus of the third embodiment will be described.

First, on the cleaned substrate 1, an electrode 1 made of polycrystalline silicon is formed by using a normal photolithography technique.
1, 12 are formed. Next, by the ion implantation method,
The electrodes 11 and 12 were doped with phosphorus. The phosphorus concentration in the electrodes 11 and 12 varies depending on the location, and is 1 × 10 20 c
^Within the range of m ⁻³ to 1 × 10 18 cm ⁻³ , the resistivity at 1 × 10 20 cm ⁻³ is 1 × 10 −2 Ω · c.
m, the resistivity at 1 × 10 18 cm ^-3 is 10 Ω
・ Cm.

Then, in the positive electrode 11 from the D ₁ side to D
_{To the 1000} side, and in the negative electrode 12 from the D ₁₀₀₀ side to the D ₁ side, the phosphorus concentration becomes lighter from 1 × 10 20 cm ⁻³ to 1 × 10 18 cm ⁻³ , At the same time, the resistivity is 1 × 10 −2 Ω · cm to 10 Ω ·
It has grown to cm.

Next, organic Pd (ccp4230 manufactured by Okuno Chemical Industries Co., Ltd.) was spin-coated on the substrate 1 on which the electrodes 11 and 12 were formed by a spinner and heated and baked at 250 ° C. for 10 minutes.

Then, the fired thin film 3 is patterned by using a normal photolithography technique so that the width b of the conductive thin film 3 becomes 300 μm as in the case shown in FIG. 10B. The electron emission part was formed.

Next, a glass spacer having a thickness of 5 mm is provided on the substrate 1, and a phosphor substrate in which a phosphor is uniformly applied is provided on the spacer 1, and then the whole is housed in the measurement and evaluation system shown in the figure. The electron emission characteristics were confirmed at an acceleration voltage of 1 kV while maintaining a vacuum degree of about 1 × 10 −6 torr. The connection method of the power supply, the positive electrode of the D ₁ side of the electrode 11, 12, D
_{The 1000} side was grounded.

As a result, bright spots corresponding to each emitting portion were observed, and the brightness of each bright spot was visually almost uniform. Also,
When the variation in each luminance was measured using a spot luminance meter, the variation was within 5%.

Embodiment 4 FIG. 13 shows a display panel using the above-mentioned surface conduction electron-emitting device as an electron source, and can display image information provided from various image information sources such as television broadcasting. It is a diagram showing an example of an image forming apparatus of the present invention configured as described above.

In the figure, 16100 is a display panel, 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 including 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, etc. of audio information 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 the image signal.

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, and examples thereof include NTSC system, PAL system and SEC.
Any method such as AM method may be used. Further, a TV signal having a larger number of scanning lines than these, for example, a so-called high-definition TV such as 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. Is the 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 wire 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 display device to an external computer, a computer network, or an output device such as 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 that stores image patterns corresponding to character codes, a processor for image processing, etc. , And the circuits necessary for image generation are incorporated.

The display image data generated by this circuit is output to the decoder 16104, but in some cases, it may 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 other purposes. For example, it may be directly related 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 which requires an image memory for reverse conversion, for example, including the MUSE system.

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 image signals within one screen display time, it is 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 the operation sequence of a power supply (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.
It operates 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 present 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 included.
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 particularly mentioned in the description of this embodiment, a dedicated circuit for processing and editing audio information may be provided as in the above-mentioned image processing and image editing.

Therefore, the present image forming apparatus includes a display device for television broadcasting, a terminal device for video conference, an image editing device for handling still images and moving images, a terminal device for 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. 13 shows only 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. It goes without saying that the present invention is not limited to this.

For example, among the constituent elements shown in FIG. 13, circuits relating to functions unnecessary for the purpose of use may be omitted.
On the contrary, the constituent elements may be added depending on the purpose of use. For example, when the display device is applied as a videophone, a TV camera, a voice microphone,
It is preferable to add a 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 can easily have a large screen, has high brightness, and has excellent viewing angle characteristics, so that the image forming apparatus has a realistic and powerful image. Can be displayed with good visibility.

[0151]

As described above, according to the present invention,
The voltage drop caused by the wiring resistance between the surface conduction electron-emitting devices is made constant to reduce the variation in the voltage applied between the surface conduction electron-emitting devices, so that the electrons are emitted from each surface conduction electron-emitting device. Thus, an image forming apparatus such as a display apparatus having a high quality image can be obtained by making the amount of electron beams to be uniform.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an equivalent circuit, potentials, and applied voltages when surface conduction electron-emitting devices are connected in parallel in the present invention.

FIG. 2 is a schematic configuration diagram showing a planar surface conduction electron-emitting device of the present invention.

FIG. 3 is a schematic configuration diagram showing a vertical surface conduction electron-emitting device of the present invention.

FIG. 4 is a diagram showing a method for manufacturing a surface conduction electron-emitting device of the present invention.

FIG. 5 is a diagram showing an example of forming waveforms.

FIG. 6 is a schematic configuration diagram showing an example of a measurement / evaluation system of the surface conduction electron-emitting device of the present invention.

FIG. 7: Emission current of the surface conduction electron-emitting device of the present invention-
It is a figure which shows an element voltage characteristic (IV characteristic).

FIG. 8 is a schematic plan view of an electron source in a ladder arrangement.

FIG. 9 is a schematic configuration diagram of a display panel used in the image forming apparatus of the present invention using a trapezoidal electron source.

FIG. 10 is a schematic configuration diagram illustrating an image forming apparatus according to a first exemplary embodiment.

FIG. 11 is a schematic configuration diagram illustrating an image forming apparatus according to a second exemplary embodiment.

FIG. 12 is a schematic configuration diagram illustrating an image forming apparatus according to a third exemplary embodiment.

FIG. 13 is a block diagram illustrating an image forming apparatus according to a fourth exemplary embodiment.

FIG. 14 is an explanatory diagram showing an equivalent circuit, a potential, and an applied voltage when surface conduction electron-emitting devices are connected in parallel according to a conventional example.

FIG. 15 is an explanatory diagram showing an equivalent circuit, potentials, and applied voltages when surface conduction electron-emitting devices are connected in parallel according to another conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Base 2 Electron emission part 3 Thin film 4,5 Element electrode 11 Positive electrode 12 Electrode 21 Step forming member 50 Ammeter 51 for measuring element current If 51 Power supply 52 Ammeter 53 for measuring emission current Ie High-voltage power supply 54 Anode electrode 55 Vacuum device 56 Exhaust pump 57 Gas introduction pipe 111 Rear plate 112 Support frame 116 Face plate 118 Enclosure 301 Display panel 302 Grid electrode 303 Open 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 Face circuit 16110 image input memory interface circuit 16111 image input interface circuit 16112 TV signal reception circuit 16113 TV signal reception circuit 16114 input

 ─────────────────────────────────────────────────── ─── Continued front page (72) Inventor Ichiro Nomura 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Hidetoshi Haru 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Incorporated (72) Inventor Shinichi Kawate 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (6)

[Claims] 1. An image forming apparatus using an electron source in which a plurality of surface conduction electron-emitting devices, each having a conductive thin film formed between device electrodes on a substrate, are electrically connected to each other. At least 2 wiring resistance
An image forming apparatus having different values of at least one kind. 2. The image forming apparatus according to claim 1, wherein the means for setting the wiring resistance value to a different value is formed by changing the wiring width. 3. The image forming apparatus according to claim 1, wherein the means for changing the wiring resistance value is different by changing the wiring thickness. 4. The image forming apparatus according to claim 1, wherein the means for adjusting the wiring resistance values to different values is formed by changing the wiring composition. 5. The positive electrode side extraction electrode of a plurality of surface conduction electron-emitting devices connected in parallel is arranged at one end of the positive electrode side electrode of the element array, and the negative electrode side extraction electrode is formed at the other end of the negative electrode side electrode of the element array. The image forming apparatus according to any one of claims 1 to 4, wherein the wiring resistance value between the surface conduction electron-emitting device elements is increased as the distance from the extraction electrode increases. 6. An image forming apparatus using an electron source in which N surface-conduction electron-emitting devices, each having a conductive thin film formed between device electrodes on a substrate, are electrically connected to each other. The positive electrode side extraction electrode of the surface conduction electron-emitting device is arranged at one end of the positive electrode side electrode of the device row,
The negative electrode side extraction electrode is arranged at the other end of the negative electrode side electrode of the element array, and the resistance value of the positive electrode side wiring connecting the i-th and (i + 1) th surface conduction electron-emitting devices from the side where the positive electrode side electrode is taken out. Is represented by r _i and the resistance value of the negative electrode side wiring is represented by r ′ _Ni , the resistance value is (N−i) r _i = (N−i) r ′
_5. The image forming apparatus according to claim 1, wherein the relationship of _i = r _Ni = r ′ _Ni is satisfied.