JPH08162003A - Surface conductive electron emission element, electron source and image forming device using it - Google Patents

Abstract

PURPOSE: To reduce forming power, and also to stabilize electron emission characteristics of a surface conductive electron emission element to be used as an electron source of an image forming device. CONSTITUTION: In a surface conductive electron emission element wherein an electron emitting part 2 is provided on a conductive thin film 3 extending over electron electrodes 4, 5 by electrification forming, the conductive thin film 3 is formed of mixture of high melting point particulates 7 and low melting point particulates 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface conduction electron-emitting device, an electron source provided with a plurality of such devices, and an image forming apparatus such as a display device and an exposure device configured by using the electron source.

[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 done at both ends of the conductive thin film.
It is usually done by applying a voltage and energizing, locally destroying, deforming or altering the conductive thin film to change the structure,
This is a process of forming an electron emitting portion having a high electrical resistance. 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 charged beam source and 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 may be an electron source in which a plurality of rows (also referred to as a common wiring) are arranged in rows (also referred to as a ladder arrangement) (JP-A-64-31332 and JP-A-1-2).
No. 83749, Japanese Patent Laid-Open No. 2-257552).

Further, particularly in the case of the display device, a surface conduction electron emission device can be used as a self-luminous display device which can be a flat panel display device similar to the display device using liquid crystal and does not require a backlight. A display device has been proposed (US Pat. No. 5,066,883) in which an electron source in which a large number of elements are arranged and a phosphor which emits visible light when irradiated with an electron beam from the electron source are combined.

[0007]

In the case of the surface conduction electron-emitting device in which the electron-emitting portion is formed on a part of the conductive thin film by the above-mentioned forming treatment, the power required for forming and the electron-emitting portion are required. Properties and the like greatly depend on the film quality (film thickness, resistance, etc.) of the conductive thin film.

Regarding the forming power, particularly in the case of an electron source in which a large number of surface conduction electron-emitting devices are formed in an array, if a large current is required for forming one device, a large number of surface conduction electron-emitting devices are simultaneously energized. Is difficult to perform, and requires an expensive forming device because it requires a large amount of power,
At the same time, it is required to use an expensive wiring material having high electric conductivity in order to increase the electric capacity of the wiring.

Regarding the electron emission characteristics of the device which are influenced by the properties of the electron emission portion, the above-mentioned crack shape changes due to the concentration of current in the electron emission portion during the driving of the element, and the electron emission characteristic changes with time. It could change to.

In view of the above circumstances, the present invention has as its main object to reduce the forming power in the surface conduction electron-emitting device and at the same time improve the stability of electron emission characteristics.

[0011]

Means and Actions for Solving the Problems The constitution of the present invention made to achieve the above object is as follows.

A first aspect of the present invention is a surface conduction electron-emitting device in which an electron-emitting portion is provided in a conductive thin film extending between a pair of device electrodes, wherein the conductive thin films have at least two different melting points. A surface conduction electron-emitting device characterized by comprising a mixture of fine particles of various types.

The first aspect of the present invention is further characterized in that, in the electroconductive thin film, the vicinity of the electron-emitting portion has a higher abundance ratio of the high melting point fine particles to the low melting point fine particles than the other portions, and the surface. The conduction electron-emitting device is a flat type in which a pair of device electrodes are formed on the same surface, and the surface conduction electron-emitting device is such that the device electrodes are vertically arranged with an insulating layer interposed therebetween. It also includes a vertical type in which a conductive thin film including an electron emitting portion is formed on a side surface of the insulating layer.

A second aspect of the present invention is an electron source characterized in that a plurality of the surface conduction electron-emitting devices according to the first aspect of the present invention are provided on a substrate.

The second aspect of the present invention is further characterized in that the electron source has at least one element array in which a plurality of surface conduction electron-emitting devices are arranged, and drives each surface conduction electron-emitting device. Wiring for performing the above is arranged in a matrix, and the electron source has at least one or more element rows in which a plurality of surface-conduction electron-emitting devices are arranged. It also includes that the wiring is arranged in a ladder.

Further, a third aspect of the present invention comprises the above-mentioned second electron source of the present invention and an image forming member which forms an image by irradiation of an electron beam from the electron source. On the device.

As described above, the present invention provides a surface conduction electron-emitting device, an electron source using the surface conduction electron-emitting device,
The present invention relates to an image forming apparatus using the electron source, and the configuration and operation of each invention will be further described below.

The surface conduction electron-emitting device of the present invention includes a planar type and a vertical type. First, the basic structure of the planar type surface conduction electron-emitting device will be described.

The basic structure of the planar surface conduction electron-emitting device is as shown in FIG. 1, where 1 is a substrate,
2 is an electron emitting portion, 3 is a conductive thin film including the electron emitting portion 2,
4 and 5 are element 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 and Pd, and Pd, Ag, Au, RuO ₂ , Pd-A
It is appropriately selected from a printed conductor composed of a metal such as g 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.

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

The element electrode interval L is preferably several hundred Å to several hundred μm, and more preferably several μm to several tens μm depending on the voltage applied between the element electrodes 4 and 5.

The device electrode length W is preferably several μm to several hundreds μm, and the device electrode thickness d is several hundred Å to several μm, considering the resistance value of the electrodes and the electron emission characteristics.

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

The conductive thin film 3 is composed of a mixture of at least two kinds of fine particles having different melting points. Examples of the material of the high melting point fine particles as the first component include metals such as W, Ta, Mo, Ir and Cr, and alloys thereof, metal oxides and metal carbides thereof. Further, as the material of the low melting point fine particles as the second component, for example, Au, Ag, Cu, Ni, Zn,
Examples thereof include metals such as Pd, Sn, Pb, alloys thereof, and metal oxides thereof. The particle size of these fine particles is preferably 1 nm to 50 nm.

The film thickness of the conductive thin film 3 is appropriately set according to the step coverage to the device electrodes 4 and 5, the electric resistance value between the device electrodes 4 and 5, the forming conditions described later, and the like.

The electric resistance value of the conductive thin film 3 can be controlled by the number of fine particles per unit area and the mixing ratio of the high melting point fine particles and the low melting point fine particles, and can be set to a value suitable for forming.

The thickness of this conductive thin film 3 is preferably 1
0Å to 1000Å, particularly preferably 100Å to 300
Å, and the resistance value is a sheet resistance value of 10 ³ to 10 ⁷ Ω / □.

A crack is included in the electron emitting portion 2, and the electron is emitted from the vicinity of the 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 Å to several hundred Å. 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 surface conduction electron-emitting device will be described.

FIG. 2 is a view showing the basic structure of a vertical surface conduction electron-emitting device, in which 21 is a step forming member,
Other reference numerals that are the same as those in FIG. 1 indicate 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 distance L (see FIG. 1) of the planar surface conduction electron-emitting device described above. It is set by the voltage applied between 5 and the electric field strength capable of emitting electrons, but is preferably several hundred Å to several tens of μm, and particularly preferably several hundred Å to several μm.

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 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, the forming conditions to be described later, and the like. The position and shape are not limited to the position and shape shown in FIG.

In the following description, of the above-mentioned planar surface conduction electron-emitting device and vertical surface conduction electron-emitting device,
A plane type will be described as an example, but a vertical type may be used.

An example of a method of manufacturing the surface conduction electron-emitting device of the present invention will be described below with reference to the manufacturing process diagram of FIG. 3 by taking the surface conduction electron-emitting device having the structure shown in FIG. 1 as an example.

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 the substrate 1 is formed by a photolithography technique or a printing method. The device electrodes 4 and 5 are formed on the surface of the substrate (FIG. 3A).

2) On the substrate 1 provided with the device electrodes 4 and 5,
Sputtering method, CVD method, electron beam heating evaporation method,
Alternatively, for example, high melting point fine particles are formed using a method of applying an organic metal compound and heating and baking, and then low melting point fine particles are similarly formed. The fine particle film thus formed is patterned by lift-off, etching or the like to form the conductive thin film 3 having a desired pattern (FIG. 3B). The organic metal solution is a solution of an organic compound whose main element is the metal of the fine particle material forming the conductive thin film 3 described above.

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 portion of the conductive thin film 3. By this energization treatment, the conductive thin film 3 is locally destroyed, deformed or altered, and the site where the structure is changed is the electron emitting portion 2 (FIG. 3C).

As the conductive thin film 3, W, Ta, Mo described above is used.
When a high melting point metal such as is used, the film resistance is small and a large amount of electric power is required to deform the film. Therefore, it was necessary to flow a large current through the film during the forming step. on the other hand,
When a low melting point metal such as Au, Ag, or Pd described above is used as the conductive thin film 3, the power required for the forming is very small, but the electron emitting portion structurally changes due to continuous driving for a long time. The electron emission characteristics were easy to change and deteriorate with time.

In the surface conduction electron-emitting device of the present invention, since the mixed fine particle film of high melting point fine particles and low melting point fine particles as described above is used as the conductive thin film 3, the energization condition in the forming step is appropriate. By selecting, the low melting point fine particles are deformed, moved or evaporated, but the high melting point fine particles are hardly changed. As a result, the forming can be completed with a very small electric power as compared with the case where the conductive thin film 3 is composed of only the high melting point material.

In addition, the surface conduction electron-emitting device of the present invention which has undergone the above-described forming is one of the conductive thin films 3,
The abundance ratio of the high melting point fine particles to the low melting point fine particles is higher in the vicinity of the electron emitting portion 2 including the cracks formed by forming than in the other portions. Therefore, it is difficult for the electron emitting portion 2 to change its shape while the device is driven, and stable electron emission can be obtained.

An example of the voltage waveform of the above forming is shown in FIG.

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. 4A) and a case where a voltage pulse is applied while increasing the pulse peak value (FIG. 4B).

First, the case where the pulse peak value is a constant voltage will be described. In FIG. 4A, T1 and T2 are the pulse width and pulse interval of the voltage waveform, for example, T1 is 1 μsec to 10 msec, T2 is 10 μsec to 100 msec,
The peak value (peak voltage during forming) is appropriately selected according to the form of the surface conduction electron-emitting device described above, and is 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 where the voltage pulse is applied while increasing the pulse peak value will be described. T1 and T2 in FIG. 4 (b) are the same as those in FIG. 4 (a), and the peak value (peak voltage during forming) is increased by, for example, about 0.1 V step, and FIG. The application is performed under an appropriate vacuum atmosphere similar to the description of 1.

In the pulse interval T2, the conductive thin film 3
(See FIGS. 1 and 2) A resistance value is obtained by measuring the device current at a voltage that does not locally break, deform, or alter the characteristics, for example, a voltage of about 0.1 V, and a resistance of 1 M ohm or more is shown. Sometimes forming ends.

4) The surface conduction electron-emitting device of the present invention comprises
It is preferable to further perform an activation step.

The activation step is, for example, 10 ⁻⁴ to 10 ⁻⁵ T.
As with the description in the forming step, it means a process of repeating the application of pulses with a pulse peak value of a constant voltage at a degree of vacuum of about orr, which is used to remove carbon and carbon compounds from an organic substance existing in a vacuum atmosphere. By depositing on the emission part 2 (see FIGS. 1 and 2), the state of the device current and the emission current can be remarkably 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. The pulse peak value in the activation step is preferably the peak value of the drive voltage applied when driving the element.

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 Å or less, more preferably 300 Å or less.

The basic characteristics of the surface conduction electron-emitting device of the present invention thus obtained will be described below.

FIG. 5 is a schematic block diagram showing an example of a measurement / evaluation system for measuring the electron emission characteristics of the surface conduction electron-emitting device. First, this measurement / evaluation system will be described.

5, 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 thin 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, and 52 is a measurement of the emission current Ie emitted from the electron emission portion 2. An ammeter, 55 is a vacuum device, and 56 is an exhaust pump.

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. It should be noted that this measurement / evaluation system uses a vacuum device 55 for the display panel and the inside thereof at the stage of assembling the display panel (see 201 in FIG. 8) as described later.
And the inside thereof, it can be applied to the measurement evaluation and processing in the above-mentioned forming step and activation step.

The basic characteristics of the surface conduction electron-emitting device described below are that the voltage of the anodic electrode 54 of the above measurement and evaluation system is 1 kV to 10 kV and the distance H between the anodic electrode 54 and the surface conduction electron-emitting device is H. Is set to 2 mm to 8 mm, and normal measurement is performed.

First, the emission current Ie and the device current If,
FIG. 6 (solid line in the figure) shows a typical example of the relationship of the element voltage Vf.
Shown in In FIG. 6, the emission current Ie is the device current Ie.
Since it is significantly smaller than f, it is shown in arbitrary units.

As is apparent from FIG. 6, the surface conduction electron-emitting device has the following three characteristic characteristics with respect to the emission current Ie.

First, in the surface conduction electron-emitting device, when a device voltage Vf higher than a certain voltage (called threshold voltage: Vth in FIG. 6) 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 the 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. 5) 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 characteristic shown by the solid line in FIG. 6 is the emission current Ie.
Has an MI characteristic with respect to the element voltage Vf, and at the same time, the element current If also has an MI characteristic with respect to the element voltage Vf. However, as indicated by a broken line in FIG. 6, the element current If becomes the element voltage Vf. On the other hand, it may exhibit a voltage control type negative resistance characteristic (called a VCNR characteristic). Which characteristic is exhibited is
It depends on the manufacturing method of the device and the measurement conditions at the time of measurement. However,
Even if the device current If has a VCNR characteristic with respect to the device voltage Vf, the emission current Ie is M with respect to the device voltage Vf.
It has the I characteristic.

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

Next, the arrangement of the surface conduction electron-emitting devices in the electron source of the present invention 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 ladder arrangement as described in the section of the prior art, n Ys 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 the surface conduction electron-emitting device. This is hereinafter referred to as a simple matrix arrangement. First, this simple matrix arrangement will be described in detail.

According to the basic characteristics of the surface conduction electron-emitting device described above, when the applied device voltage Vf exceeds the threshold voltage Vth, the electron is generated at the peak value and pulse width of the applied pulsed voltage. The amount of release can be controlled. On the other hand, below the threshold voltage Vth, almost no electrons are emitted. Therefore, even when a large number of surface conduction electron-emitting devices are arranged, it becomes possible to apply a pulsed voltage controlled according to an input signal only by simple matrix wiring, select individual devices and drive them independently. .

The simple matrix arrangement is based on the above principle, and the structure of the electron source of 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. 7, 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 arranged on the substrate 1 are appropriately set according to the application. Is.

The m X-direction wirings 102 have external terminals Dx1, Dx2, ... Dxm, respectively.
A conductive metal or the like formed on the upper surface 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 directional wirings 103 and electrically separated to form a matrix wiring. In addition, both m and n are positive integers.

The interlayer insulating layer (not shown) is SiO ₂ or the like formed by a vacuum deposition 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.

Furthermore, the opposing device electrodes (not shown) of the surface conduction electron-emitting device 104 are m number of X-direction wirings 102.
And 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, the m X-direction wirings 102, the n Y-direction wirings 103, the connection lines 105, and the opposing element electrodes may have the same or a part of the constituent elements, Further, they may be different from each other, and are appropriately selected from the above-mentioned material of the device electrode and the like. The wiring to these element electrodes may be generically referred to as an element electrode when the same material as the element electrode is used. 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, a modulation signal (not shown) is applied to the Y-direction wiring 103 in order to modulate each row of the surface conduction electron-emitting devices 104 arranged in the Y-direction according to an input signal. The signal applying means is electrically connected. 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 device.

Next, an example of the image forming apparatus of the present invention using the electron source of the present invention having the above simple matrix arrangement will be described with reference to FIGS. 8 is a basic configuration diagram of the display panel 201, FIG. 9 is a diagram showing the fluorescent film 114, and FIG. 10 is the display panel 201 of FIG.
It is a block diagram showing an example of a drive circuit for performing a television display according to an SC system television signal.

In FIG. 8, 1 is a substrate of an electron source in which the surface conduction electron-emitting device 104 is arranged as described above, and 1
Reference numeral 11 is a rear plate on which the substrate 1 is fixed, 116 is a face plate having a fluorescent film 114, which is an image forming member, a metal back 115 and the like formed on the inner surface of a glass substrate 113, and 112 is a support frame. . Rear plate 111,
The support frame 112 and the face plate 116 are sealed by applying frit glass or the like to their joints and baking them at 400 ° C. to 500 ° C. for 10 minutes or more in the air or a nitrogen atmosphere to seal them. The envelope 118 is configured.

In FIG. 8, 2 corresponds to the electron emitting portion in FIG. Reference numerals 102 and 103 denote a pair of device electrodes 4 and 5 of the surface conduction electron-emitting device 104 (see FIGS. 1 and 2).
The X-direction wiring and the Y-direction wiring connected to each have 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, and when the substrate 1 itself has sufficient strength, the rear plate 1 is a separate body.
11, the support frame 112 may be directly sealed to the substrate 1, and the face plate 116, the support frame 112, and the substrate 1 may constitute the envelope 118. Further, by further installing a support body (not shown) called a spacer between the face plate 116 and the rear plate 111, it is possible to form the envelope 118 having sufficient strength against atmospheric pressure.

The fluorescent film 114 is composed of only the fluorescent material 122 in the case of monochrome, but is composed of the fluorescent material 1 in the case of color.
22 stripes, black stripes (Fig. 9 (a))
Alternatively, it is composed of a black conductive material 121 called a black matrix (FIG. 9B) and the like, and a phosphor 122.
The purpose of providing the black stripes and the black matrix is to provide each of the three primary color phosphors 12 required for color display.
It is to make the color-mixed portions between the two black so as to make the color mixture inconspicuous and to suppress the deterioration of the contrast due to the reflection of external light on the fluorescent film 114. Black conductive material 12
As the material of No. 1, not only a commonly used material containing graphite as a main component, but also another material can be used as long as it is a material having conductivity and little transmission and reflection of light.

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.

Further, 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. 9) toward the inner surface side to face the face plate 11.
6 to improve the brightness by specular reflection, to act as an electrode for applying an electron beam accelerating voltage from the high voltage terminal Hv, and to prevent damage due to collision of negative ions generated in the envelope 118. For example, protection of the fluorescent substance 122 from the light. 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 vapor deposition 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.

In the case of the above-mentioned sealing, in the case of a color, each color phosphor 122 and the SCE surface conduction electron-emitting device must correspond to each other, so that it is necessary to perform sufficient alignment.

The inside of the envelope 118 is sealed with a vacuum degree of about 10 ⁻⁷ Torr through an exhaust pipe (not shown).
Further, the getter process may be performed immediately before or after the envelope 118 is sealed. This is to heat a getter (not shown) arranged at a predetermined position in the envelope 118 by a heating method such as resistance heating or high frequency heating.
This is a process of forming a vapor deposition film. The getter usually contains Ba or the like as a main component.
^{This is} for maintaining a vacuum degree of ^-5 to 10 ^-7 Torr.

Incidentally, the above-mentioned forming process and the subsequent manufacturing process of the surface conduction electron-emitting device are usually performed in the envelope 1.
It is performed immediately before or after the sealing of 18, and the content thereof is as described above.

The above-mentioned display panel 201 is shown in FIG.
It can be driven by a driving circuit as shown in FIG.
In FIG. 10, 201 is the 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 sync signal separation circuit, 207 is a modulation signal generator, and Vx and Va are DC voltage sources.

As shown in FIG. 10, 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 Dx
For xm, a surface conduction electron-emitting device provided in the display panel 201, that is, a group of devices arranged in a matrix of m rows and n columns is sequentially driven row by row (n elements). Scanning signal is applied.

On the other hand, the external terminals Dy1 to Dyn are connected to
A modulation signal for controlling the output electron beam of each element in one row selected by the scanning signal is applied. Further, the high voltage terminal Hv is, for example, 10 kV from the DC voltage source Va.
DC voltage is supplied. 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 has therein m switching elements (schematically shown by S1 to Sm in FIG. 10).
Each of the switching elements S1 to Sm selects either the output voltage of the DC voltage source Vx or 0V (ground level) and is electrically connected to the external terminals Dx1 to Dxm of the display panel 201. It is a thing. 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.

In the DC voltage source Vx in this example, the drive voltage applied to the surface scanning electron-emitting device which is not scanned is equal to or lower than the threshold voltage based on the characteristics (threshold voltage) of the SCE. It is set to output such a constant voltage.

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

The sync signal separation circuit 206 is a circuit for separating a sync signal component and a luminance signal component from an NTSC television signal input from the outside, and as is well known, a frequency separation (filter ) Using a circuit,
It can be easily constructed. Sync signal separation circuit 206
The synchronizing signal separated by means of a vertical synchronizing signal and a horizontal synchronizing signal are also 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 serial / parallel conversion of 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, it may be said that the shift clock is four. Also,
One line of serial / parallel converted image (corresponding to driving data for n elements of the 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, and stores the contents of Id1 to Idn in accordance with the control signal Tmry sent from the control circuit 203. The stored contents are output as I′d1 to I′dn and input to the modulation signal generator 207.

The modulation signal generator 207 is a signal line for appropriately driving and modulating each of the surface conduction electron-emitting devices according to each of the image data I'd1 to I'dn.
The output signal is applied to the surface conduction electron-emitting device in the display panel 201 through the external 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. For voltages exceeding the threshold voltage,
The emission current also changes according to the change in the voltage applied to the 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 be changed by changing the material, structure, and manufacturing method of the surface conduction electron-emitting device. I can say things.

That is, when a pulsed voltage is applied to the surface conduction electron-emitting device, electron emission does not occur 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, firstly, 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 the 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 uses a voltage modulation method circuit that generates a voltage pulse of a constant length, but can appropriately modulate the pulse peak value according to the 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 circuit of the pulse width modulation method capable of appropriately modulating the pulse width according to the input data is used. To use.

The shift register 204 and the line memory 20
5 may be of 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 done by providing an A / D converter at the output of the sync signal separation circuit 206.

Further, 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 the modulation signal generator 207 is slightly different.

That is, in the case of the voltage modulation method using a digital signal, for example, a well-known D / A conversion circuit may be used as the modulation signal generator 207, and an amplification circuit or the like may be added if necessary. Further, in the case of a pulse width modulation method using a digital signal, the modulation signal generator 207, for example, a high-speed oscillator and a counter (counter) that counts the number of waves output by the oscillator, and the output value of the counter and the 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 analog signals, the modulation signal generator 207 may be an amplifier circuit using, for example, a well-known operational amplifier, 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 of the present invention having the display panel 201 and the driving circuit as described above has the external terminals Dx1 to Dx1.
By applying a voltage from Dxm and Dy1 to Dyn, electrons can be emitted from any surface conduction electron-emitting device 104, and a high voltage is applied to the metal back 115 or the transparent electrode (not shown) through the high voltage terminal Hv. And accelerates the electron beam, and the accelerated electron beam is applied to the fluorescent film 1.
The excitation / emission generated by colliding with N
A television display can be performed according to a TSC 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 taken as an example of 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. The TV signal may be a high-definition TV system such as the MUSE system.

Next, an example of the above-mentioned ladder-type electron source and an image forming apparatus of the present invention using the electron source will be described with reference to FIGS. 11 and 12.

In FIG. 11, 1 is a substrate, 104 is a surface conduction electron-emitting device, 304 is a common wiring for connecting the surface conduction electron-emitting device 104, and 10 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. A plurality of these element rows 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 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 driving voltage is performed on the common wirings D2 to D9 located between the element rows by the common wirings 304 adjacent to each other, that is, the external terminals D adjacent to each other.
The common wiring 304 of 2 and D3, D4 and D5, D6 and D7, and D8 and D9 can also be formed as an integrated same wiring.

FIG. 12 is a diagram showing the structure of a display panel 301 having the above-mentioned ladder-type electron sources.

In FIG. 12, 302 is a grid electrode,
Reference numeral 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 Gn are terminals 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. 12, the same reference numerals as those in FIG. 8 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 electrodes provided orthogonally to the device rows 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
The shape is not necessarily shown in FIG. 12, and a large number of openings 303 may be provided in a mesh shape, and the grid electrode 302 may be provided, for example, in the surface conduction electron-emitting device 10.
It may be provided around 4 or in the vicinity thereof.

The external terminals D1 to Dm and G1 to Gn are connected to a drive circuit (not shown). Then, in synchronization with the sequential driving (scanning) of the element rows one column at a time, a modulation signal for one line of the image is applied to the columns of the grid electrode 302, so that each electron beam is applied to the fluorescent film 114. The irradiation can be controlled and the image can be displayed line by line.

As described above, the image forming apparatus of the present invention is
An image formation that can be obtained by using the electron source of the present invention in either a simple matrix arrangement or a trapezoidal arrangement and is suitable not only as a display device for the television broadcast described above but also as a display device for a video conference system, a computer, or the like. The device is obtained. Further, it can also be used as an exposure device of an optical printer constituted by a photosensitive drum and the like.

[0121]

EXAMPLES The present invention will be further described with reference to the following examples.

Example 1 In this example, an example in which a surface conduction electron-emitting device having the structure shown in FIG. 1 was manufactured will be described. FIG. 1A is a plan view of a surface conduction electron-emitting device,
FIG.1 (b) has shown sectional drawing. In the figure, L represents the distance between the device electrodes 4 and 5, W1 represents the device electrode width, and W2 represents the conductive thin film 3 width.

A method of manufacturing the surface conduction electron-emitting device of this embodiment will be described with reference to FIG.

1) A quartz substrate is used as the substrate 1, which is thoroughly washed with an organic solvent, a resist mask is formed on the substrate 1 by a photolithography technique, and then Ni as an element electrode material is formed by a vacuum deposition method. Was deposited. Thereafter, the element electrode interval L is set to 1 by the lift-off method.
Element electrodes 4 and 5 having a width of 0 μm and a width W1 of 500 μm were formed (FIG. 3A).

2) After forming a Cr thin film on the substrate 1 on which the device electrodes 4 and 5 are formed, by a photography technique,
The Cr mask was created by removing the region where the conductive thin film 3 was formed. Further, W was deposited by the sputter deposition method to form W fine particles on the substrate 1. At this time, the W fine particles had an average particle diameter of about 5 nm, and the particles were discretely distributed on the substrate 1. Subsequently, Au was vapor-deposited by the same sputter vapor deposition method to form Au fine particles on the substrate 1.
At this time, the average particle diameter of Au was about 6 nm, and the Au particles were distributed so as to fill the gaps between the W fine particles previously formed (FIG. 3).
(B)).

3) Next, the substrate 1 on which the element electrodes 4, 5 and the conductive thin film 3 are formed is placed in the vacuum device 55 of the measurement / evaluation system of FIG. The inside of the vacuum device 55 was set to a vacuum degree of about 10 ⁻⁵ Torr. After that, a voltage was applied between the device electrodes 4 and 5 by the power supply 51 for applying the device voltage Vf, and a forming process was performed to form the electron emitting portion 2 (FIG. 3C). The voltage waveform shown in FIG. 4B was used for the forming process.

In this embodiment, T1 in FIG. 4B is set to 1 m.
Second, T2 was set to 10 msec, and the peak value of the triangular wave was gradually increased until the forming was completed. as a result,
In this example, the peak value at the completion of forming was about 5V.

In the element of this embodiment, the conductive thin film 3 is made of W
Compared to the comparative element prepared in exactly the same manner as above except that it was composed of only fine particles, the forming power was about 5 on average.
Could be reduced by a factor of one.

The electron emission characteristics of the surface conduction electron-emitting device of this example were measured using the above-mentioned measurement evaluation system.

The measurement conditions were that the distance H between the anode electrode 54 and the surface conduction electron-emitting device was 4 mm, and the anode electrode 5 was 5 mm.
The potential of 4 is 1 kV, the vacuum device 55 at the time of measuring electron emission characteristics
The degree of vacuum inside was about 1 × 10 ⁻⁶ Torr.

As a result, the element of this example obtained the current-voltage characteristics shown by the solid line in FIG. 6 even after being manufactured several times. The characteristic of a typical element is the element voltage V
At f = 14V, the device current If = 1.5 mA and the emission current Ie = 0.8 μA.

Further, a comparative element was manufactured in the same manner as in this example except that the conductive thin film 3 was composed of only Au fine particles, and was continuously driven for 100 hours. Was reduced by about 20%.

On the other hand, the reduction rate of the emission current Ie after continuously driving the device in this example under the same conditions for 100 hours was about 5%.

[Embodiment 2] In this embodiment, another example of manufacturing the surface conduction electron-emitting device having the structure shown in FIG. 1 will be described.

In the element of this embodiment, iridium (I) is used as the high melting point fine particles 7 which is the first constituent element of the conductive thin film 3.
In r), palladium oxide (PdO) was used as the second constituent low melting point fine particles 8.

To form Ir fine particles on the substrate 1, the sputter vapor deposition method was used. As a method for forming PdO fine particles,
First, a method was used in which Pd was sputter-deposited on the substrate 1 and then Pd was heated and baked at 400 ° C. in the atmosphere to be oxidized. The structure of the element in the other parts and the manufacturing process are the same as in the first embodiment.

In this example, the amounts of Ir fine particles and PdO fine particles were adjusted by the respective sputtering deposition times so that the resistance value between the device electrodes 4 and 5 before forming was about 1000Ω.

As a result, the forming current was about one-tenth or less as compared with an element (element resistance value of about 10Ω) in which the conductive thin film 3 was composed of only Ir fine particles with the same structure. .

Further, a comparative element was manufactured in the same manner as in this example except that the conductive thin film 3 was composed of only PdO fine particles, and was continuously driven for 100 hours. Was reduced by about 15%.

On the other hand, the reduction rate of the emission current Ie after continuously driving the device in this example under the same conditions for 100 hours was about 5%.

[Embodiment 3] In this embodiment, an electron source as shown in FIG. 7 in which a large number of surface conduction electron-emitting devices as shown in FIG. 1 are arranged in a simple matrix is used.
An example in which the image forming apparatus as shown in FIG.

The electron source is manufactured by expanding each pattern of the device electrodes 4 and 5 and the conductive thin film 3 described in the first embodiment to form a large number of surface conduction electron-emitting devices at the same time, and simultaneously wiring in the X direction. (Also called lower wiring) 102 and Y
Directional wiring (also referred to as upper wiring) 103 was formed.

An example in which an image forming apparatus is configured by using the unformed electron source substrate manufactured as described above will be described with reference to FIGS. 8 and 9.

First, after fixing the substrate 1 of the unformed electron source to the rear plate 111, the face plate 116 (the image forming member on the inner surface of the glass substrate 113 is located 5 mm above the substrate 1). The fluorescent film 114 and the metal back 115 are formed.) The support frame 112
Through the face plate 116, the support frame 11
2. Frit glass was applied to the joint portion of the rear plate 111, and the frit glass was baked in the air at 400 ° C. to 500 ° C. for 10 minutes or more for sealing (see FIG. 8). Further, the frit glass was also used to fix the substrate 1 to the rear plate 111.

Fluorescent film 114 which is an image forming member
In the case of monochrome, it is composed of only the phosphor, but in this embodiment, the phosphor has a stripe shape (see FIG. 9A), and a black stripe is first formed with the black conductive material 121. Each color phosphor 12 is formed in the gap by the slurry method.
2 was applied to produce a fluorescent film 114. Black conductive material 12
As 1, a commonly used material containing graphite as a main component was used.

A metal back 115 is provided on the inner surface side of the fluorescent film 114. The metal back 115 is the fluorescent film 1.
After producing 14, the inner surface of the fluorescent film 114 is smoothed (usually called filming), and then A
1 was vacuum-deposited.

The face plate 116 may be provided with a transparent electrode on the outer surface side of the fluorescent film 114 in order to further increase the conductivity of the fluorescent film 114, but in this embodiment, only the metal back 115 is used. It was omitted because sufficient conductivity was obtained.

When 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 have to correspond to each other, so that sufficient alignment is performed.

The atmosphere inside the envelope 118 completed as described above is exhausted by a vacuum pump through an exhaust pipe (not shown), and after reaching a sufficient degree of vacuum, the external terminals Dx1 to Dxm.
And Dy1 to Dyn, a voltage was applied between the device electrodes 4 and 5 of each surface conduction electron-emitting device 104, and a forming process was performed in the same manner as in Example 1 to fabricate the electron-emitting portion 2.

Thereafter, the envelope 1 is passed through an exhaust pipe (not shown).
The inside of 18 was evacuated to a degree of vacuum of about 10 ^-6.5 Torr, and the exhaust pipe was heated by a gas burner to be welded to seal the envelope 118. Finally, in order to maintain the degree of vacuum after sealing, a getter process was performed by a high frequency heating method. The getter was mainly composed of Ba.

In the display panel 201 (see FIG. 8) constructed by using the electron sources having the simple matrix arrangement as described above, the external terminals Dx1 to Dxm and Dy1 to Dy are provided.
Through yn, a scanning signal and a modulation signal are applied to each surface conduction electron-emitting device 104 by a signal generating means (not shown) to emit electrons, and a high voltage of several kV or more is applied to the metal back 115 through the high voltage terminal Hv. An image is displayed by accelerating the electron beam to cause it to collide with the fluorescent film 114 to excite and emit light. As a result, since the surface conduction electron-emitting device used in this example is excellent in stability of electron emission characteristics, there is no decrease in brightness over a long period of time, and high-intensity and high-definition images are stably obtained. Could be displayed.

[Embodiment 4] FIG. 13 shows a display panel (display panel) 201 (see FIG. 8) of Embodiment 3 in which image information provided from various image information sources such as television broadcasting is displayed. It is a figure which shows an example of the image display apparatus of this invention comprised so that it could display.

In the figure, 201 is a display panel, 100
1 is a display panel drive circuit, 1002 is a display controller, 1003 is a multiplexer, 10
Reference numeral 04 is a decoder, 1005 is an input / output interface circuit, 1006 is a CPU, 1007 is an image generation circuit, 10
08, 1009 and 1010 are image memory interface circuits, 1011 are image input interface circuits,
Reference numerals 1012 and 1013 are TV signal receiving circuits and 1014 is an input unit.

When the display device receives a signal including both video information and audio information, such as a television signal, it naturally reproduces audio at the same time as displaying video. Descriptions of circuits, speakers, etc. relating to reception, separation, reproduction, processing, and storage of audio information that are not directly related to the features of the invention will be omitted.

Each section will be described below along the flow of the image signal.

First, the TV signal receiving circuit 1013 is a circuit for receiving a TV image 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, SE
Various methods such as a CAM method may be used. Further, a TV signal including a larger number of scanning lines than these, for example, a so-called high-definition TV such as the MUSE system is suitable for taking advantage of the display panel 201 suitable for a large area and a large number of pixels. It is a signal source.

T received by the TV signal receiving circuit 1013
The V signal is output to the decoder 1004.

The image TV signal receiving circuit 1012 is a circuit for receiving a TV image signal transmitted using a wired transmission system such as a coaxial cable or an optical fiber. Similar to the TV signal receiving circuit 1013, the system of the TV signal to be received is not particularly limited, and the TV signal received by this circuit is also output to the decoder 1004.

Image input interface circuit 1011
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 1004.

Image memory interface circuit 1010
Is a circuit for capturing an image signal stored in a video tape recorder (hereinafter abbreviated as VTR), and the captured image signal is output to the decoder 1004.

Image memory interface circuit 1009
Is a circuit for capturing the image signal stored in the video disc.
It is output to 04.

Image memory-interface circuit 100
Reference numeral 8 denotes a circuit for capturing an image signal from a device that stores still image data, such as a so-called still image disc. The captured still image data is decoded by a decoder 1004.
Is output to

The input / output interface circuit 1005 is
It 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 1006 of the display device and the outside.

The image generation circuit 1007 receives image data, character / graphic information, or CPU 1006 input from the outside via the input / output interface circuit 1005.
It is a circuit for generating display image data based on image data and character / graphic information output from the output. Inside this circuit, for example, a rewritable memory for accumulating image data and character / graphic information, a read-only memory that stores image patterns corresponding to character codes,
The circuits necessary for image generation, such as a processor for image processing, are incorporated.

The display image data generated by this circuit is output to the decoder 1004, but in some cases, it can be output to an external computer network or printer via the input / output interface circuit 1005.

The CPU 1006 mainly carries out operations relating to operation control of this display device and generation, selection and editing of a display image.

For example, a control signal is output to the multiplexer 1003 to appropriately select or combine image signals to be displayed on the display panel 201. At that time, a control signal is generated to the display panel controller 1002 according to the image signal to be displayed, and the screen display frequency, the scanning method (for example, interlaced or non-interlaced), the number of scanning lines in one screen, etc. are displayed. The operation of the device is controlled appropriately. In addition, image data and character / graphic information are directly output to the image generation circuit 1007,
Alternatively, the external computer or memory is accessed through the input / output interface circuit 1005 to input image data or character / graphic information.

It should be noted that the CPU 1006 may of course 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 computer may be connected to an external computer network via the input / output interface circuit 1005, and work such as numerical calculation may be performed in cooperation with an external device.

The input unit 1014 is used by the user to input commands, programs, data, etc. to the CPU 1006. For example, in addition to a keyboard and a mouse,
It is possible to use various input devices such as a joystick, a bar code reader, and a voice recognition device.

The decoder 1004 converts various image signals input from the above 1007 to 1013 into three primary color signals,
Alternatively, it is a circuit for inverse conversion into a luminance signal, an I signal, and a Q signal. In addition, as shown by a dotted line in FIG.
It is desirable that 004 has an image memory inside. This is to handle a television signal that requires an image memory for reverse conversion, such as the MUSE method.

The provision of the image memory makes it easy to display a still image. Alternatively, the image processing circuit 1007 and the CPU 1006 cooperate with each other to obtain an advantage of facilitating image processing and editing such as image thinning, interpolation, enlargement, reduction, and composition.

The multiplexer 1003 is the CPU 10
The display image is appropriately selected on the basis of the control signal input from 06. That is, the multiplexer 1003 selects a desired image signal from the inversely converted image signals input from the decoder 1004 and outputs it to the drive circuit 1001. 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 1002
Is a circuit for controlling the operation of the drive circuit 1001 based on a control signal input from the CPU 1006.

As the elements related to the basic operation of the display panel 201, for example, the display panel 201
A signal for controlling the operation sequence of the driving power source (not shown) is output to the driving circuit 1001. As a signal relating to the driving method of the display panel 201, for example, a signal for controlling a screen display frequency and a scanning method (for example, interlace or non-interlace) is output to the drive circuit 1001. In some cases, the drive circuit 10 outputs control signals relating to image quality adjustment such as brightness, contrast, color tone, and sharpness of a display image.
It may be output to 01.

The drive circuit 1001 is a circuit for generating a drive signal to be applied to the display panel 201, based on the image signal input from the multiplexer 1003 and the control signal input from the display panel controller 1002. It works.

The functions of the respective parts have been described above. With the configuration illustrated in FIG. 13, the display panel 2 displays image information input from various image information sources in this display device.
01 can be displayed. That is, various image signals such as television broadcasts are transmitted to the decoder 1004.
After being inversely converted in, the signal is appropriately selected in the multiplexer 1003 and input to the driving circuit 1001. On the other hand, the display controller 1002 generates a control signal for controlling the operation of the drive circuit 1001 according to the image signal to be displayed. The drive circuit 1001 applies a drive signal to the display panel 201 based on the image signal and the control signal. As a result, the image is displayed on the display panel 201. These series of operations are centrally controlled by the CPU 1006.

In this image forming apparatus, the image memory built in the decoder 1004 and the image generating circuit 100 are included.
7 and the CPU 1006 are involved not only to display one selected from a plurality of image information but also to enlarge, reduce, rotate, move, edge emphasize, thin out, and interpolate the displayed image information. It is also possible to perform image processing such as color conversion and aspect ratio conversion of images, and image editing such as combining, erasing, connecting, replacing, and fitting. Although not particularly mentioned in the description of the present embodiment, a dedicated circuit for performing processing and editing on 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 a video conference, an image editing device for handling still images and moving images, a terminal device for a computer, an office terminal device such as a word processor,
It is possible to combine the functions of a game console etc. with one unit,
It has an extremely wide range of applications for industrial or consumer use.

Note that FIG. 13 shows only an example of the constitution in the case of an image forming apparatus using a display panel having the surface conduction electron-emitting device of the present invention as an electron beam source, and the image of the present invention. It goes without saying that the forming device 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 image forming apparatus is applied as a videophone, it is preferable to add a television camera, a voice microphone, an illuminator, a transmission / reception circuit including a modem, and the like to the constituent elements.

In the present image forming apparatus, since the display panel 201 according to the present invention can be easily thinned, the depth of the display apparatus can be reduced. In addition, since it is easy to make a large screen, has high brightness, and has excellent viewing angle characteristics, it is possible to display a highly realistic image with high power and good visibility.

[0183]

As described above, the surface conduction electron-emitting device of the present invention is capable of easily forming with a very small electric power, and the electron-emitting portion formed thereby has high structural stability. Therefore, it is possible to maintain stable electron emission characteristics with excellent durability for a long period of time.

Further, the electron source in which a large number of surface-conduction type electron-emitting devices of the present invention are formed and the image forming apparatus using the same do not cause a decrease in the brightness even after long-time driving, and have a high brightness and a high definition image. Can be obtained stably.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a planar surface conduction electron-emitting device showing an example of a surface conduction electron-emitting device of the present invention.

FIG. 2 is a configuration diagram of a vertical type surface conduction electron-emitting device showing another example of the surface conduction electron emission device of the present invention.

FIG. 3 is a diagram illustrating an example of a method of manufacturing the surface conduction electron-emitting device of FIG.

FIG. 4 is an example of a voltage waveform used in forming processing.

FIG. 5 is a schematic diagram of a measurement evaluation system for measuring electron emission characteristics of a surface conduction electron-emitting device.

FIG. 6 is a diagram showing a typical example of the relationship between the emission current Ie and the device current If and the device voltage Vf of the surface conduction electron-emitting device of the present invention.

FIG. 7 is a schematic diagram of an electron source with a simple matrix arrangement.

FIG. 8 is a partially cutaway perspective view showing a schematic configuration of a display panel provided with an electron source having a simple matrix arrangement.

FIG. 9 is a diagram showing a configuration example of a fluorescent film used in a display panel.

FIG. 10 is a block diagram showing an example of a drive circuit of an image forming apparatus that displays an image in accordance with an NTSC television signal.

FIG. 11 is a schematic view of a ladder-type electron source.

FIG. 12 is a partial cutaway perspective view showing a schematic configuration of a display panel provided with a trapezoidal arrangement of electron sources.

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

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Substrate 2 Electron emission part 3 Conductive thin film 4,5 Element electrode 7 High melting point fine particles 8 Low melting point fine particles 21 Step forming member 50 Ammeter 51 for measuring the element current If flowing through the conductive thin film 3 Surface conduction electron emission Power supply 52 for applying the device voltage Vf to the device 52 Ammeter 53 for measuring the emission current Ie emitted from the electron emission part 2 High voltage power supply 54 for applying a voltage to the anode electrode 54 Emission from the electron emission part 2 Anode electrode for trapping generated electrons 55 Vacuum device 56 Exhaust pump 102 X-direction wiring 103 Y-direction wiring 104 Surface-conduction electron-emitting device 105 Connection wire 111 Rear plate 112 Support frame 113 Glass substrate 114 Fluorescent film 115 Metal Back 116 Face plate Hv High voltage terminal 118 Envelope 121 Black conductive material 122 Phosphor 01 Display panel 202 Scanning circuit 203 Control circuit 204 Shift register 205 Line memory 206 Synchronous signal separation circuit 207 Modulation signal generator Va DC voltage source Vx DC voltage source 301 Display panel 302 Grid electrode 303 Electron passage opening 304 Surface conduction Common wiring for wiring the electron-emitting device 104 1001 Drive circuit for the display panel 201 1002 Display controller 1003 Multiplexer 1004 Decoder 1005 Input / output interface circuit 1006 CPU 1007 Image generation circuit 1008, 1009, 1010 Image memory interface circuit 1011 Image input interface circuit 1012 , 1013 TV signal receiving circuit 1014 Input unit

Claims (8)

[Claims] 1. A surface conduction electron-emitting device in which an electron emitting portion is provided in a conductive thin film extending between a pair of device electrodes, wherein the conductive thin film is a mixture of at least two kinds of fine particles having different melting points. A surface conduction electron-emitting device comprising: 2. The surface conduction type according to claim 1, wherein, in the electroconductive thin film, the abundance ratio of the high melting point fine particles to the low melting point fine particles is larger in the vicinity of the electron emitting portion than in other portions. Electron emitting device. 3. The surface-conduction type electron-emitting device according to claim 1, wherein the surface-conduction type electron-emitting device is a planar type in which a pair of device electrodes are formed on the same surface. 4. The surface conduction electron-emitting device is a vertical type in which a pair of device electrodes are vertically arranged with an insulating layer interposed and a conductive thin film including an electron-emitting portion is formed on a side surface of the insulating layer. The surface conduction electron-emitting device according to claim 1 or 2, characterized in that it is present. 5. An electron source comprising a plurality of the surface conduction electron-emitting devices according to claim 1 on a substrate. 6. The electron source has at least one or more device rows in which a plurality of surface conduction electron-emitting devices are arranged, and wirings for driving each surface conduction electron-emitting device are arranged in a matrix. The electron source according to claim 5, wherein: 7. The electron source has at least one device row in which a plurality of surface conduction electron-emitting devices are arranged, and wirings for driving each surface conduction electron-emitting device are arranged in a ladder. The electron source according to claim 5, wherein: 8. An image forming apparatus comprising: the electron source according to claim 5; and an image forming member that forms an image by irradiation with an electron beam from the electron source.