JPH07320665A - Electron source and image forming device using it - Google Patents

Abstract

PURPOSE:To form an electron source, which can form the even elements and which can evenly discharge the electron, and to form an image forming device, which can display with the even luminance. CONSTITUTION:Electron discharging elements arranged in lines on a substrate is divided into three groups of A, B, C, and connected to each other per a group by common wirings 902A, B, C. These wirings are laminated per a group with an insulating layer 908 between them, and each element is driven by a difference of the electric potential applied to the wirings 902A, B, C and the wiring 903. Since each group is formed of the elements at 1/3 of one line, even in the case where voltage is applied from the end of the wiring, lowering of the voltage due to the resistance is small, and unevenness between each element is small at the time of forming and at the time of discharging electron. In the case where an image is formed by discharging electron, unevenness of the luminance due to the unevenness of the surface conduction type electron discharging elements is reduced, and the even display is enabled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electron source having a plurality of surface conduction electron-emitting devices and an image forming apparatus to which the electron source is applied, which makes the electron emission amount distribution and the luminance distribution obtained thereby uniform. It is a thing.

[0002]

2. Description of the Related Art Conventionally, two types of electron emitters, a thermoelectron source and a cold cathode electron source, are known.

Cold cathode electron sources include field emission type (hereinafter abbreviated as FE), metal / insulating layer / metal type (hereinafter abbreviated as MIM), and surface conduction type emission elements (hereinafter SCE: Surface Conductive).
(Abbreviated as Emitter).

As an example of the FE type, WPDyke & WWDola
n, "Field emission", Advance in Electron Physics,
8,89 (1956) and others are known.

An example of the MIM type is CAMead, "The tun
nel-emission amplifier, J.Appl.Phys., 32,646 (1961)
And CASpindt, "Physical properties of thin-film fi
eld emission cathodes with molybdenum cones ", J.Ap
pl.Phys., 47, 5248 (1976) and the like are known.

As an example of the SCE type, MIElinson, Radi
o Eng. Electron Pys., 10, (1965), etc.

The SCE utilizes a phenomenon in which electron emission occurs when a current is passed through a thin film having a small area formed on a substrate in parallel with the film surface.

As the SCE, the one using the SnO2 thin film by Erinson et al., The one using the Au thin film [G. Dittner: "Thin Solid Films", 9,317 (1972)], In
2O3 / SnO2 thin film [M.Hartwell and CGFo
nstad: "IEEE Trans.Ed COnf.", 519 (1975)], by carbon thin film [Haraki Araki et al .: Vacuum, Vol. 26, Vol. 1]
No., p. 22 (1983)] and the like.

FIG. 15 shows the above-mentioned M. Hartwell device structure as a typical device structure of these SCEs. In the figure, 1301 is an insulating substrate. Reference numeral 1302 denotes a thin film for forming an electron emitting portion, which is made of a metal oxide thin film or the like formed by sputtering on an H-shaped pattern, and the electron emitting portion 1303 is formed by an energization process called forming described later. Reference numeral 1304 is called a thin film including an electron emitting portion. In the figure, L1 is 0.5 mm to 1 mm, W1 is 0.1 mm
Is set in.

Conventionally, in these SCEs, the electron-emitting portion 130 is previously subjected to an energization process called forming before the electron-emitting portion forming thin film 1302 is emitted.
It is common to form 3. That is, the forming means that a voltage is applied to both ends of the electron emission portion forming thin film 1302 to locally destroy, deform or alter the electron emission portion forming thin film 1302, and the electron emission is made into a high electric resistance state. That is to form the portion 1303. The SCE that has undergone the forming process is one in which electrons are emitted from the electron emitting portion 1303 by applying a voltage to the thin film 1304 including the electron emitting portion and causing a current to flow on the device surface.

The above-mentioned SCE has an advantage that a large number of elements can be arrayed over a large area because it has a simple structure and is easy to manufacture. Therefore, various applications are being studied to make use of this feature. For example, a charged beam source, a display device, etc. can be used. An example of arranging a large number of SCEs is an electron source in which SCEs are arranged in parallel and a large number of rows in which both ends of each element are connected by wiring are arranged (for example, proposed by the present applicant). JP-A-1-31332). Further, in image forming apparatuses such as display devices, in particular, flat-panel display devices using liquid crystals have become widespread in place of CRTs in recent years, but since they are not self-luminous, they must have a backlight or the like. Therefore, there is a demand for the development of a self-luminous display device. An image forming apparatus, which is a display device in which a large number of SCEs are arranged and a phosphor that emits visible light by the electrons emitted from the electron source, is relatively easy to manufacture even in a large screen device, and It is a self-luminous display device with an excellent viewing angle.

[0012]

It is natural that a high-quality, high-definition image and the second screen are desired in various image forming apparatuses to which SCE is applied, including the above-mentioned flat plate type CRT. Requires a very large array of elements, each having several hundreds to several thousands of rows and columns of electron sources, and is desired to have uniform element characteristics. The method of connecting a large number of elements in these devices that has been proposed so far is, for example, in the form of a ladder in the image forming apparatus as described in JP-A-1-31332, or by the inventors. In the method described above, the wirings are connected in a simple matrix, and all the elements in the same column are connected to at least one common wiring. The ends of these common wires are connected to external terminals, and when these elements are subjected to the above-mentioned forming process or driven, energization is performed by injecting a current from the ends of the common wires. However, the large-scale electron source has the following problems.

Due to the voltage drop caused by the wiring resistance, the applied voltage becomes lower as the element is connected farther from the feeding point of the common wiring, and the amount of emitted electrons and the luminance are lowered. At this time, the amount of voltage drop due to the wiring changes depending on the amount of current flowing through the element connected to the drive circuit.

As described above, in the present device, the film is modified by an energization process called forming, and the device is manufactured. However, since many SCEs are connected to one common wiring, the above-mentioned JP-A-1- Not only in the case of parallel connection like No. 31332 but also in the case of simple matrix connection, usually, a plurality of elements of a certain specific unit such as a column unit or a row unit are simultaneously formed.

Here, although the current required for forming varies depending on the manufacturing method and configuration, for example, it is necessary to flow a current of about 30 mA per element as an instantaneous value, and if a forming current for several hundred elements simultaneously flows. Then, the total current becomes 10 A or more in an instantaneous value. At this time, due to the voltage drop due to the wiring resistance, the applied voltage becomes higher as the element is closer to the power feeding point to the common wiring, and the forming process is completed first. Further, the applied voltage to the element connected far from the feeding point gradually rises, and sometimes rises sharply immediately before forming. That is, all elements are not formed under the same conditions, and a distribution occurs in element characteristics.

Further, for example, in an image forming apparatus in which only one side of the common wiring is connected to the drive circuit, when a certain scanning line is turned on, the luminance of the pixel on the side to which the drive circuit is connected is 100. Then, the brightness of the pixel on the opposite side is low, about 70, but when only the pixel on the opposite side to which the drive circuit is connected is turned on, the pixel is turned on with a brightness of about 100. In this way, there occurs a phenomenon in which the luminance changes depending on the light emission pattern, which becomes more remarkable as the scale of the matrix increases.

Due to such a problem, although the SCE has the advantage that the device structure is simple, it has not been industrially applied positively.

In view of such conventional problems, the present invention has
The object of the present invention is to provide an electron source and an image forming apparatus having a uniform electron emission amount or brightness.

[0019]

[Means for Solving the Problems] and

In order to solve the above-mentioned problem, the present invention has a plurality of groups of cold cathode elements (three groups A, B and C in FIG. 1) in which common wirings are multi-layered and arranged in a line as shown in FIG. ) And connect to the power supply for each group. The cold cathode element is formed at each intersection of the column wiring 903 and the row wiring 902, and a voltage is applied. Longitudinal wiring and horizontal wiring are insulators 9
It is formed so as to be separated by 06. The row wirings are independent as wirings 902A, 902B, 902C for each group of cold cathode devices.

In FIG. 1, the common wirings of each group are separated by forming multiple layers, but they may be separated in the same plane as in FIG. In FIG. 2, the horizontal wirings include the wirings 902A ′ and 9 which are independent in the group A and the group B.
It is divided into 02B 'and is independently supplied with power. The wirings 902A 'and 902B' are formed on the same plane.

In the electron source and the image forming apparatus in which the cold cathode elements are wired for each group according to the present invention, various cold cathode elements including the conventional cold cathode element can be used.

Among the cold cathode devices, the surface conduction electron-emitting device is particularly preferable. That is, the M
The IM type element needs to control the thickness of the insulating layer and the upper electrode relatively precisely, and the FE type needs to precisely control the tip shape of the needle-shaped electron emitting portion. Therefore, these elements may have a relatively high manufacturing cost, or it may be difficult to manufacture a large area device due to restrictions in the manufacturing process.

On the other hand, the surface conduction electron-emitting device has a simple structure and is easy to manufacture, and a large-area one can be easily manufactured. In recent years, it can be said that this is a particularly suitable cold cathode element particularly in a situation where an inexpensive display device having a large screen is required.

Further, in the case of the surface conduction electron-emitting device, the method of the present invention can exhibit not only the effect of driving character but also the effect superior to the conventional one at the time of forming.

Further, the inventors of the present application have found that among the surface conduction electron-emitting devices, the one in which the electron-emitting portion or its peripheral portion is formed of a fine particle film is preferable in view of characteristics or large area. .

Therefore, an image forming apparatus using a surface conduction electron-emitting device formed of a fine particle film as a cold cathode device will be described as a preferred example of the present invention.

The basic structure and manufacturing method of the electron source according to the present invention will be described below with reference to FIGS. 4, 5 and 6.

FIG. 4 shows the basic structure of a single element of the SCE used in the electron source of the present invention (portion 509 in FIG. 5).
FIG. In the figure, 401 is an insulating substrate,
Reference numerals 405 and 406 are electrodes, 404 is a thin film including an electron emitting portion, and 403 is an electron emitting portion.

The thin film 40 including the electron emitting portion in the present invention
3, the electron emitting portion 403 is made of conductive fine particles having a particle diameter of several tens of angstroms, and the thin film 404 including the electron emitting portion except the electron emitting portion 403 is made of a fine particle film. The fine particle film described here is a film in which a plurality of fine particles are aggregated, and its fine structure is not only in a state in which the fine particles are individually dispersed and arranged but also in a state in which the fine particles are adjacent to each other or overlap each other (also in an island shape). Including) film.

In addition to this, the thin film 404 including the electron emitting portion may be a carbon thin film in which conductive fine particles are dispersed. Pd, Ru, Ag, Au, Ti, In, and C are given as specific examples of the thin film 404 including the electron emitting portion.
Metals such as u, Cr, Fe, Zn, Sn, Ta, W, Pb, oxides such as PdO, SnO2, In2O3, PbO, Sb2O3, HfB2, ZrB2, LaB6, CeB6, YB.
4, boride such as GdB4, Tic, ZrC, HfC, Ta
Carbides such as C, SiC, WC, TiN, ZrN, HfN
Such as nitrides, semiconductors such as Si and Ge, carbon, Ag
Mg, NiCu, Pb, Sn and the like.

The thin film 404 including the electron emitting portion is formed by vacuum vapor deposition, sputtering, chemical vapor deposition, dispersion coating,
It is formed by a dipping method, a spinner method, or the like.

Various methods are conceivable as a method of manufacturing an SCE having an electron emitting portion, one example of which is shown in FIG. In the figure, reference numeral 602 denotes a thin film for forming an electron emitting portion, which is, for example, a fine particle film.

The manufacturing method will be described below step by step.

(1) After the insulating substrate 601 is thoroughly washed with a detergent, pure water and an organic solvent, a common wiring having a power supply wiring and a device electrode is formed on the surface of the insulating substrate 601 by a vacuum deposition technique and a photolithography technique. The wiring 605, the same 606, and an insulating layer are formed. When the power supply wiring is the lowermost layer, the power supply wiring is formed on the substrate 601, and the common wirings 605 and 606 are formed thereon via the insulating layer (FIG. 6).
(A)). On the contrary, when the power supply wiring is not the lowermost layer, the common wirings 605 and 606 in the lower layer are formed and then the power supply wiring is formed through the insulating layer. Any material may be used as the wiring material as long as it has conductivity. For example, nickel metal may be used, and the electrode interval L1 is 2 μm.
The electrode length W1 (see FIG. 4) is 300 μm, the wiring 605,
The film thickness d of the element electrode portion of 606 is 1000 angstrom.

(2) An organometallic thin film is formed by applying an organometallic solution between the wiring 605 and the wiring 606 provided on the insulating substrate 601, and leaving it to stand. The organic metal solution is the above-mentioned Pd, Ru, Ag, A
u, Ti, In, Cu, Cr, Fe, Sn, Ta, W,
It is a solution of an organic compound whose main element is a metal such as Pb.
After that, the organic metal film is subjected to a heating treatment by heating, and is patterned by lift-off, etching or the like to form a thin film 602 for forming an electron emitting portion (FIG. 6B).

(3) Next, when an energization process called forming is performed between the element electrodes provided on the wirings 605 and 606 of FIG. 6 by a pulse 602 or a high-speed rising voltage by an unillustrated power supply, Thin film for forming emission part 60
An electron emitting portion 3 having a changed structure is formed at the portion 2 (FIG. 6C). This energization process locally destroys, deforms or modifies the electron emission portion forming thin film 602,
The site where the structure is changed is called an electron emitting portion 603. As described above, the present inventors have observed that the electron emitting portion 603 is composed of conductive fine particles.

FIG. 13 shows the voltage waveform of the forming process. In FIG. 13, T1 and T2 are the pulse width and pulse interval of the voltage waveform.
2 was set to 10 microseconds to 100 milliseconds, the peak value of the triangular wave (peak voltage during forming) was set to about 4V to 10V, and the forming treatment was appropriately set in a vacuum atmosphere for about several tens of seconds.

Since the wiring of each group is separated, the applied voltage can be set independently for each group. That is, in the group far from the feeding point, the applied voltage can be set high considering the voltage drop due to the wiring resistance.

When forming the electron emitting portion described above,
Although the triangular wave pulse is applied between the electrodes of the element to perform the forming process, the waveform applied between the electrodes of the element is not limited to the triangular wave, and a desired waveform such as a rectangular wave may be used. The high value, the pulse width, the pulse interval, and the like are not limited to the above values, and a desired value can be selected as long as the electron emitting portion is well formed.

The basic characteristics of the SCE according to the present invention produced by the above element structure and manufacturing method will be described with reference to FIGS. 7 and 8.

FIG. 7 is a schematic configuration diagram of a measurement / evaluation apparatus for measuring the electron emission characteristics of the element having the configuration shown in FIG. In FIG. 7, 401 is an insulating substrate, and 405.
Reference numerals 406 and 406 denote device electrodes, 404 a thin film including an electron emitting portion, and 403 an electron emitting portion. Further, 731 is a power supply for applying the element voltage Vf to the element, 730 is an ammeter for measuring the element If flowing in the thin film 404 including the electron emitting portion between the element electrodes 405 and 406, and 734 is electron emission of the element. An anode electrode for capturing Ie emitted from the device, 733 is a high-voltage power supply for applying an acceleration voltage Va to the anode electrode 734, and 732 is an electron emitting portion 40 of the device.
3 is an ammeter for measuring the emission current Ie emitted from the device 3.

The above device current If and emission current Ie of SCE
For the measurement of, the power supply 7 is applied to the device electrodes 405 and 406.
31 and an ammeter 730 are connected, and an anode electrode 734 in which a power source 733 and an ammeter 732 are connected above the SCE.
Are arranged. Also, the SCE and the anode electrode 73
4 is installed in a vacuum device, and the vacuum device is equipped with equipment necessary for the vacuum device such as an exhaust pump and a vacuum gauge (not shown) so that the measurement and evaluation of this element can be performed under a desired vacuum. Has become.

The electrode Va of the anode electrode is 1 kV to
10 kV, distance H between anode electrode and SCE is 3 mm ~
It was measured in the range of 8 mm.

FIG. 8 shows a typical example of the relationship between the emission current Ie and the device current If and the device voltage Vf measured by the measurement / evaluation apparatus shown in FIG. Note that FIG. 8 is shown in arbitrary units and has three characteristics with respect to the emission current Ie.

First, in the present device, when a device voltage higher than a certain voltage (called threshold voltage, Vth in FIG. 8) is applied, the emission current Ie rapidly increases, while the threshold voltage Vth is increased. In the following, the emission current Ie is hardly detected.
That is, a clear threshold voltage V with respect to the emission current Ie
It is a non-linear element having th.

Secondly, the emission current Ie depends on the device voltage Vf. Further, there is a region where the electron emission current Ie is almost proportional to If.

Thirdly, the emitted charges captured by the anode electrode 734 depend on the time for which the device voltage Vf is applied.
That is, the amount of charge captured by the anode electrode 734 is
It can be controlled by the time for which the element voltage Vf is applied.

Due to the above characteristics, the SCE according to the present invention can be expected to be applied to various fields. For example, in the case of forming an image forming panel, the brightness of a pixel is determined by the total amount of energy of electrons with which a phosphor is irradiated within a unit time. Since the accelerating voltage Va applied between the electron source and the anode 734 is applied almost constant to any pixel, the brightness of the pixel is determined by the amount of electrons emitted from the electron source and the electron emission time.

Here, in the case where the common wiring of each group is common only in the connection portion with the drive circuit, the output voltage of the drive circuit must be changed even if the amount of current flowing in a certain group changes greatly. For example, the voltage applied to the other groups does not change. That is, by reducing the number of elements commonly connected in the middle of a certain element and the drive circuit, the amount of change in luminance due to the difference in the light emission pattern can be reduced.

[0050]

EXAMPLE One example of an image forming apparatus to which the present invention is applied will be shown below.

FIG. 5 shows a plan view of a part of the electron source in which the SCE 509 is arranged by the common wiring of the display panel shown in FIG. 9 is a sectional view taken along the line AA ′ in the figure.
Here, 901 is a substrate, 902 is a matrix lower wiring, 90
Reference numeral 3 is a matrix wiring, 904 is an electron emission portion forming thin film, 905 is an element electrode, 906 is an interlayer insulator, and 908 is a lead wiring of another group.

Next, the manufacturing method will be concretely described with reference to FIGS.

Step-a (FIG. 10 (a)) Cr having a thickness of 50 A (angstrom) and Au having a thickness of 6000 A were sequentially laminated on a cleaned substrate 1001 made of soda-lime glass by vacuum evaporation, and then a photoresist ( AZ1370 Rexist) is spin coated with a spinner, baked, and then exposed and developed with a photomask image,
A lower wiring resist pattern is formed, and the Au / Cr deposition mark is wet-etched to form a lower wiring 902.

Step-b (FIG. 10B) Next, the interlayer insulating layer 9 made of a silicon oxide film having a thickness of 1 μm.
06 is deposited by the RF sputtering method.

Step-c (FIGS. 10 (c1), (c2),
(C3) In order to form the interlayer insulating layer 906 only under the upper wiring, a photoresist pattern is formed on the silicon oxide film deposited in step-b, and the interlayer insulating layer 906 is etched using this as a mask. For etching, R using CF4 and H2 gas is used.
According to the IE (Reacrive Ion Etching) method. Here, in the multi-layer portion, the correlation insulating layer laminated on the lead-out wiring 908 is left as it is, and the wirings and the correlation insulating layer are multilayered by further repeating steps-a and b, and only the uppermost insulating layer is formed. Pattern. (C2) shows a two-layer structure, and (c3) shows a three-layer structure. It is also possible to remove the insulating layer at the end portion of the substrate to which the drive circuit is connected and share each layer in this portion (FIG. 17).

Step-d (FIG. 11 (d)) After that, a pattern to be the device electrode 905 and the device electrode gap G is formed with a photosensor resist (RD-2000N).
-41 made by Hitachi Chemical Co., Ltd.), and Ni having a heat thickness of 50 A and a Ti thickness of 1000 A was sequentially deposited by a vacuum evaporation method.
Dissolve the photoresist pattern with an organic solvent, and use Ni / Ti
The deposited film was lifted off to form an element electrode 905 having an element electrode gap G. Here, the gap between the device electrodes is 2 μm.

Step-e (FIG. 11E) After forming a host resist pattern for the upper wiring on the device electrode 905, Ti having a heat of 50 A and Au having a thickness of 500 A are formed.
Then, unnecessary portions were removed by lift-off in order by vacuum vapor deposition to form upper wiring 903.

Step-f (FIG. 11 (f)) A Cr film 909 having a film thickness of 1000 A is deposited by vacuum evaporation so as to have an inter-device gap G and an opening in the vicinity thereof.
After patterning, organic Pd (ccp4230
Okuno Seiyaku Co., Ltd.) spin coated with a spinner and baked to form an electron emission portion forming thin film 904 made of Pd particles.
To form.

Step-g (FIGS. 12 (g1), (g2),
(G3)) Cr film 909 and thin film 904 for forming an electron emission portion after firing
Was wet-etched with an acid etchant to form a desired pattern. Steps-c to g are performed on the uppermost layer. The results of step-g are as follows: (g1) for one layer, (g2) for two layers, and three layers. It shows in (g3).

Through the above steps, a multilayer lower wiring 902, an interlayer insulating layer 906, an upper wiring 903, an element electrode 905, an electron emission portion forming thin film 904, etc. are formed on the same substrate, and a SCE simple matrix wiring substrate is formed. It was made. Although the above steps are examples using thin film, photolinography, etching, and other techniques, printing, which is a wiring forming technique, may be used, and various other techniques may be used.

Further, there is a degree of freedom in the material of each member, and for example, the wiring material may be one normally used as an electrode material, such as Au, Ag, Cu, Al, Ni, W, Ti, Cr.
And so on. As the interlayer insulating layer 906, other than the silicon oxide film, MgO, TiO2, Ta2O5, Al2O3, and a laminate or mixture thereof can be used. Further, as the element electrode 905, one having conductivity other than the wiring materials mentioned above may be used.

Next, referring to FIG. 3, the electron-emitting device is manufactured as described above, and the face plate 310 (the fluorescent film 30 is formed on the inner surface of the glass substrate 307) 5 mm above the substrate 301.
8 and a metal back 309 are formed) are arranged via a support frame 303, frit glass is applied to the joint portion of the rear plate 302, and the temperature is 400 ° C. to 500 ° C. for 10 minutes in the air or a nitrogen atmosphere. It was sealed by firing as above. The frit glass was also used to fix the substrate 301 to the rear plate 302. 304 is an electron emitting portion,
305 and 306 are element electrodes in the row direction and the column direction, respectively. The lead wires provided on the above-mentioned substrate are connected to the terminals Dx1 to Dxm or Dy1 to Dyn outside the container.

In this embodiment, the face plate 310, the support frame 303, and the rear plate 302 constitute the envelope 311 as described above, but the rear plate 302 is mainly the substrate 3.
01 is provided for the purpose of reinforcing the strength of the substrate 30.
Separate rear plate 3 if 1 itself has sufficient strength
02 is unnecessary, the support frame 303 is directly sealed to the substrate 301, and the face plate 310, the support frame 303, and the substrate 3 are attached.
The envelope 311 may be configured with 01.

In the case of monochrome, the fluorescent film 308 is composed of only the phosphor, but in the case of a color fluorescent film, it is composed of a black conductive material called a black stripe or a black matrix depending on the arrangement of the phosphor and a phosphor. It

The purpose of providing the black stripes and the black matrix is to make the color mixture of the three primary color phosphors, which is necessary for color display, different from each other by making the portions of the three primary color phosphors different from each other to be inconspicuous. This is to suppress a decrease in contrast due to reflection of external light at 308. In this embodiment, the fluorescent material has a stripe shape, a black stripe is first formed, and the fluorescent material of each color is applied to the gaps to form the fluorescent film 308. As a material for the black stripe, a material containing graphite as a main component, which is usually well used, was used, but the material is not limited to this as long as it is a material having conductivity and little light passage and reflection.

As a method for applying the phosphor to the glass substrate 307, a precipitation method or a printing method is used in the case of monochrome, but a slurry method is used in this embodiment of color.
Even in the case of color, the same coating film can be obtained by using the printing method.

A metal back 309 is usually provided on the inner surface of the fluorescent film 308. The purpose of the metal back is to allow the light emitted from the phosphor to the inner surface side to be emitted from the face plate 31.
Improves brightness by specular reflection to the 0 side, acts as an electrode for applying an electron beam accelerating voltage, protects the phosphor from damage due to collision of negative ions generated in the envelope, etc. is there.

The metal back was produced by producing a phosphor film, smoothing the inner surface of the phosphor film (usually called filming), and then vacuum-depositing Al.

The face plate 310 may be provided with a transparent electrode (not shown) on the outer surface side of the fluorescent film 308 in order to further enhance the conductivity of the fluorescent film 308, but in this embodiment, only a metal back is provided. Since sufficient conductivity was obtained with, it was omitted.

At the time of performing the above-mentioned sealing, in the case of color, the phosphors of the respective colors have to correspond to the electron-emitting devices, so that sufficient alignment is performed.

The atmosphere in the glass container 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. Through the element electrodes 405, 4
06 (see FIG. 4), a voltage was applied, and the above-mentioned forming was performed to form the electron-emitting portion 304, thereby manufacturing the electron-emitting device.

The forming pulse Vform has a pulse waveform shown in FIG. 13, in which T1 is 1 msec, T2 is 10 msec, the peak voltage is 5 V, and the forming process is about 1 × 10 ^-6 to.
It was performed for 60 seconds in a vacuum atmosphere of rr.

The electron-emitting portion thus produced was in a state in which fine particles containing palladium element as a main component were dispersed and arranged, and the average particle diameter of the fine particles was 30A.

After the forming of all SCE elements is completed as described above, finally, with a vacuum degree of about 10 ^-6 torr,
Weld by heating the exhaust pipe (not shown) with a gas burner,
The envelope was sealed.

Finally, in order to maintain the degree of vacuum after sealing,
Getter processing was performed. This is a process of heating a getter arranged at a predetermined position (not shown) in an image forming panel by a heating method such as resistance heating or high frequency heating immediately before or after sealing to form a vapor deposition film. Is. The getter usually has Ba or the like as a main component, and maintains the degree of vacuum by the adsorption action of the vapor deposition film.

In the image forming panel of the present invention completed as described above, each electron-emitting device has a terminal Dx1 outside the container.
Through Dxm and Dy1 through Dyn, electrons are emitted by applying a voltage, and through the high voltage terminal Hv,
An image was displayed by applying a high voltage of several kV or more to the metal back 309 or a transparent electrode (not shown), accelerating the electron beam, causing the electron beam to collide with the fluorescent film 308, and exciting and emitting light.

The structure described above is a schematic structure necessary for producing the image forming panel, and the detailed parts such as the materials of the respective members are not limited to the above contents, but are applicable to the use of the image forming panel. Choose as appropriate.

With such a structure, an electron source capable of uniform electron emission can be realized, and an image forming panel having a uniform brightness distribution characteristic by a light emission pattern and having no change can be obtained. To be

Further, even during forming, since the forming voltage can be prevented from lowering due to the wiring resistance, each element can be formed uniformly.

<Application to Image Forming Apparatus> Next, an image forming apparatus to which the image forming panel having the above structure is applied will be described.

FIG. 14 is a diagram showing an example of a display device configured to display image information provided from various image information sources such as television broadcasting on the display panel described above. is there. 12 in the figure
00 is a display panel, 1201 is a display panel drive circuit, 1202 is a display controller, 1203 is a multiplexer, 1204 is a decoder,
1205 is an input / output interface circuit, 1206 is C
PU, 1207 is an image generation circuit, 1208 and 120.
9 and 1210 are image memory interface circuits,
Reference numeral 1211 is an image input interface circuit, 1212 and 1213 are TV signal receiving circuits, and 1214 is an input unit.

(It should be noted that in this figure, a processing circuit and a speaker related to the audio component of each input signal such as a television are omitted.) Hereinafter, the function of each section will be described along the flow of the image signal. Do it.

First, the TV signal receiving circuit 1213 is a circuit for receiving a TV image signal transmitted using a wireless transmission system such as radio waves or spatial optical communication. The system of the TV signal to be received is not particularly limited, and for example, various systems such as NTSC system, PAL system and SECAM system may be used. Further, a TV signal (for example, a so-called high-definition TV such as the MUSE system) including a larger number of scanning lines than this is suitable for taking advantage of the display panel suitable for a large area and a large number of pixels. It is a signal source. The TV signal received by the TV signal receiving circuit 1213 is output to the decoder 1214.

The TV signal receiving circuit 1212 is a circuit for receiving a TV image signal transmitted by using a wired transmission system such as a coaxial cable or an optical fiber. Similar to the TV signal receiving circuit 1213, 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 1204.

Further, the image input interface circuit 12
Reference numeral 11 denotes a circuit for capturing an image signal supplied from an image input device such as a TV camera or an image reading scanner. The captured image signal is a decoder 1204.
Is output to.

Further, the image memory interface circuit 1
210 is a video tape recorder (hereinafter abbreviated as VTR)
The circuit for fetching the image signal stored in is output to the decoder 1204.

Further, the image memory interface circuit 1
Reference numeral 209 is a circuit for capturing the image signal stored in the video disc, and the captured image signal is output to the decoder 1204.

Further, the image memory interface circuit 1
Reference numeral 208 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 the decoder 12
It is output to 04.

Further, the input / output interface circuit 120
Reference numeral 5 is a circuit for connecting the present 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 1206 of the display device and the outside.

Further, the image generation circuit 1207 is provided with image data, character / graphic information, or CPU which is externally input through the input / output interface circuit 1205.
This is a circuit for generating display image data based on image data and character / graphic information output from 1206. Inside this circuit, for example, a rewritable memory for accumulating image data and character / graphic information, a read-only memory in which an image pattern corresponding to a character code is stored, a processor for performing 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 1204, but in some cases, it can be output to an external computer network or printer via the input / output interface circuit 1205.

Further, the CPU 1206 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 1203 to appropriately select or combine image signals to be displayed on the display panel. At that time, a control signal is generated to the display panel controller 1202 in accordance with 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.

Image data or character / graphic information is directly output to the image generation circuit 1207, or an external computer or memory is accessed via the input / output interface circuit 1205 to generate image data or character / figure information. Enter graphic information.

It should be noted that the CPU 1206 may of course be involved in work for purposes other than this. For example,
It may be directly related to the function of generating and processing information, such as a personal computer or a word processor.

Alternatively, as described above, the input / output interface circuit 1205 may be connected to an external computer network to perform work such as numerical calculation in cooperation with an external device.

The input unit 1214 is the CPU 12
A user inputs commands, programs, data, etc. at 06. For example, various input devices such as a keyboard, a mouse, a joystick, a bar code reader, and a voice recognition device can be used.

Further, the decoder 1204 has the above-mentioned 1207.
Is a circuit for reverse-converting various image signals input from Nos. 1213 to 3 primary color signals or luminance signals and I signals and Q signals. It is desirable that the decoder 1204 has an image memory therein, as indicated by a dotted line in the figure. This is for handling a television signal that requires an image memory for reverse conversion, including the MUSE system. Further, the provision of the image memory makes it easy to display a still image, or facilitates image processing and editing including image thinning, interpolation, enlargement, and synthesis in cooperation with the image generation circuit 1207 and the CPU 1206. This is because the advantage of being able to do it is born.

Further, the multiplexer 1203 uses the C
The display image is appropriately selected based on the control signal input from the PU 1206. That is, the multiplexer 1203 selects a desired image signal from the inversely converted image signals input from the decoder 1204 and outputs it to the drive circuit 1201. 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. .

Also, the display panel controller 1
Reference numeral 202 is a circuit for controlling the operation of the drive circuit 1201 based on a control signal input from the CPU 1206.

First, regarding the basic operation of the display panel, for example, a signal for controlling the operation sequence of a power source (not shown) for driving the display panel is output to the drive circuit 1201.

Further, regarding the driving method of the display panel, a signal for controlling the screen display frequency and the scanning method (for example, interlace or non-interlace) is output to the drive circuit 1201.

In some cases, a control signal relating to image quality adjustment such as brightness, contrast, color tone and sharpness of a display image may be output to the drive circuit 1201.

The drive circuit 1201 is a circuit for generating a drive signal to be applied to the display panel 1200, and the image signal input from the multiplexer 1203 and the display panel controller 12 are used.
It operates on the basis of a control signal inputted from 02.

The functions of the respective parts have been described above. With the configuration illustrated in FIG. 14, the display panel 1 displays image information input from various image information sources in this display device.
It is possible to display at 200. That is, various image signals such as television broadcasts are transmitted to the decoder 12
After inverse conversion in 04, multiplexer 1203
Are selected as appropriate in (1) and input to the drive circuit 1201. On the other hand, the display controller 1202 generates a control signal for controlling the operation of the drive circuit 1201 according to the image signal to be displayed. The drive circuit 1201 applies a drive signal to the display panel 1200 based on the image signal and the control signal. As a result, the image is displayed on the display panel 1200. A series of these operations is controlled by the CPU 1206 as a whole.

Further, in this display device, the image memory built in the decoder 1204 and the image generation circuit 12 are provided.
Due to the involvement of the CPU 07 and the CPU 1206, not only is it possible to display a long-lasting image from a plurality of pieces of image information, but also enlargement, reduction, rotation, movement, edge enhancement, thinning, Interpolation, color conversion,
It is also possible to perform image processing such as image aspect ratio conversion, and image editing such as composition, deletion, connection, replacement, and fitting. Further, although not particularly mentioned in the description of the present embodiment, a dedicated circuit for processing and editing voice information may be provided as in the above-mentioned image processing and image editing.

Therefore, the present display device has functions of a display device for television broadcasting, a terminal device for video conference, an image editing device, a computer terminal device, an office terminal device such as a word processor, and a game machine. It can be combined with a stand, and has a very wide range of applications for industrial or consumer use. Moreover, since the display panel can be easily thinned, the depth of the device can be reduced. In addition, it is possible to display a highly realistic image with good visibility because it is easy to enlarge the screen, has high brightness, and has excellent viewing angle characteristics.

[0108]

Other Embodiments In the first embodiment, the wiring is multi-layered, but naturally the same effect can be obtained by using wiring patterns (FIG. 2) separated in the same plane.

Also, an example of grouping in which adjacent elements are made into the same group has been shown, but the present invention is not necessarily limited to this. For example, every other group is divided into three groups as the same group. However, the same effect can be obtained.

FIG. 16 shows a ladder-type array of three elements a, b, and c with every second element as one group.
It is a figure which shows the example divided into groups. FIG. 16A is a top view thereof, and a thin film 904 is formed between the common wirings 902. This thin film contains an electron emitting portion.
The common wiring 902 is laminated in three layers on the substrate, and each layer is insulated by the correlation insulating layer 906.

FIG. 16B shows a- of the elements of group a.
It is an a'sectional view. The elements of group a are connected to the uppermost wiring. FIG. 16C shows bb ′ of group b.
In cross section, it is connected to the middle wiring. FIG. 16 (d)
Is a sectional view taken along the line cc 'of the group c, which is connected to the wiring of the lowermost layer.

By wiring in this way, the number of elements connected to one wiring is reduced, so that it is possible to prevent the emitted charges of the elements located away from the power supply terminal from being lowered by the voltage drop. Further, if this is applied to an image display device, it is possible to prevent the luminance of the pixel corresponding to each element from decreasing as the distance from the power supply terminal increases.

When the electron source configured as shown in FIG. 16 is applied to a color display device, color display can be performed by associating a group for each wiring with each color component. For example, the three groups in FIG. 16 are made to correspond to red, green, and blue signals respectively, and the phosphors corresponding to the elements of each group are made red, green, and blue, respectively, and power is independently supplied to each wiring. With this configuration, it is possible to easily change the element voltage for each element group corresponding to each color in order to correct the characteristic difference between the phosphors of each color.

[0114]

As described above, the electron source of the present invention is
The effect that the distribution of the amount of electron emission does not depend on the energization element pattern can be obtained, and the effect that uniform forming is possible at the time of forming can be obtained.

Further, the image forming apparatus to which it is applied has an effect that there is no variation in luminance and the display quality is high.

[Brief description of drawings]

FIG. 1 is a plan view and a sectional view showing a basic configuration of an electron source substrate.

FIG. 2 is a plan view showing another configuration of the electron source substrate.

FIG. 3 is a perspective sectional view showing a configuration of an image forming panel using a simple matrix wiring SCE.

FIG. 4 is a diagram showing a configuration of an SCE single element.

FIG. 5 is a diagram showing a simple matrix wiring SCE.

FIG. 6 is a diagram showing a manufacturing process of an SCE single element.

FIG. 7 is a diagram showing an SCE characteristic measuring instrument.

FIG. 8 is a diagram showing SCE characteristics.

FIG. 9 is a cross-sectional view of a matrix-sourced electron source substrate.

FIG. 10 is a diagram showing a manufacturing process of a matrix wiring SCE.

FIG. 11 is a diagram showing a manufacturing process of a matrix wiring SCE.

FIG. 12 is a diagram showing a manufacturing process of a matrix wiring SCE.

FIG. 13 is a diagram showing a forming pulse shape.

FIG. 14 is a diagram showing a configuration of an image forming apparatus.

FIG. 15 is a diagram showing a configuration of a conventional SCE single element.

FIG. 16 is a diagram showing a configuration of an electron source substrate of another example.

FIG. 17 is a cross-sectional view showing a configuration in which wiring is shared in the electron source substrate of the example.

[Explanation of symbols]

 301 Substrate 302 Rear Plate 303 Support Frame 304 Electron Emitting Section 305 Row Direction Wiring 306 Column Direction Wiring 307 Glass Substrate 308 Fluorescent Film 309 Metal Back 310 Face Plate 311 Envelope 401 Insulating Substrate 402 Electron Emitting Section Forming Film 403 Electron Emission Part 404 thin film including electron emission part 405 electrode 406 electrode 730 ammeter 731 power supply 732 ammeter 733 power supply 734 anode electrode 901 insulating substrate 902 lower wiring 903 upper wiring 904 electron emission portion forming thin film 905 device electrode 906 interlayer insulating layer

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location H01J 1/30 Z 31/15 C 37/073 // H01L 21/027

Claims (15)

[Claims] 1. An electron source in which a plurality of cold cathode electron-emitting devices driven by a potential difference between two electrodes are arranged in a matrix, and one electrode of the device is connected in each row in each predetermined group. An electron source comprising: a row wiring; an applying unit that applies a predetermined voltage to the row wiring; and a unit that applies a voltage to the other electrode of the element. 2. The electron source according to claim 1, wherein the row wiring for each group is laminated with an insulating layer interposed therebetween. 3. The electron source according to claim 1, wherein the row wirings for each of the groups are provided in parallel in the same plane. 4. The electron source according to claim 2, wherein the row wirings of each group are connected to each other, and the applying unit applies a predetermined voltage to each wiring from the connecting portion. 5. The electron source according to claim 1, wherein each of the predetermined groups is configured by collecting electron-emitting devices included in each row at a predetermined number. 6. The electron source according to claim 1, wherein the cold cathode electron source is a surface conduction electron-emitting device. 7. The electron source according to claim 6, wherein the surface conduction electron-emitting device includes an electron emitting portion made of fine particles. 8. An electron source comprising a plurality of cold cathode electron-emitting devices arranged in a matrix, which are driven by a potential difference between two electrodes,
An image forming apparatus for forming an image based on an image signal, comprising row wirings for connecting one electrode of the element in each row for each predetermined group, application means for applying a predetermined voltage to the row wirings, and An image forming method comprising: a means for applying a signal corresponding to the image signal to the other electrode; and a means for forming an image according to the charge of electrons emitted from the cold cathode electron-emitting device. apparatus. 9. The image forming apparatus according to claim 8, wherein the row wirings for each group are laminated with an insulating layer interposed therebetween. 10. The row wiring for each group is provided in parallel in the same plane.
The image forming apparatus described. 11. The image forming apparatus according to claim 9, wherein the row wirings of each group are connected to each other, and the applying unit applies a predetermined voltage to each wiring from the connection point. 12. The image forming apparatus according to claim 8, wherein each of the predetermined groups is configured by collecting electron-emitting devices included in each row at a predetermined number. 13. The image forming apparatus according to claim 8, wherein the cold cathode electron source is a surface conduction electron-emitting device. 14. The image forming apparatus according to claim 13, wherein the surface conduction electron-emitting device includes an electron emitting portion made of fine particles. 15. The image forming apparatus according to claim 12, wherein each of the predetermined groups corresponds to a color element forming a color image.