JPH09230819A - Image forming device, method and circuit for driving it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device preventing a locus of an electronic beam form shifting even when luminance is adjusted by providing a means simultaneously adjusting an applied voltage to an electron emission element and the applied voltage to a target. SOLUTION: A pulse width modulation circuit 106 outputs a voltage signal with a fixed amplitude modulating a pulse width according to the image data to apply it to terminals Dyl-Dyn of a display panel 101. In this case, a luminance adjustment circuit 107 outputs an indication of an output value to a drive voltage applying means 108 which imparts an amplitude of a voltage pulse at the time and a scan circuit 102. Then, the luminance adjustment circuit 107 outputs the indication for varying Vf, Va while keeping a ratio between the amplitude Vf of the voltage pulse and an acceleration voltage Va imparted to a high voltage terminal on a face plate to a fixed level according to an indication signal inputted from an external adjustment terminal. Thus, a shift of the electronic beam due to luminance adjustment is eliminated, and the problems such as a color smear, etc., in the image forming device are prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus provided with a multi electron beam source in which a plurality of electron-emitting devices are arranged in a matrix, a driving circuit and a driving method thereof.

[0002]

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

[0003] As a surface conduction type emission element, for example,
M. I. Elinson, Radio Eng. Ele
ctron Phys. , 10, 1290, (196
5) and other examples described later are known.

The surface conduction electron-emitting device utilizes a phenomenon in which an electron is emitted when a current flows in a small-area thin film formed on a substrate in parallel with the film surface. As this surface conduction type emission element, Sn described by Elinson et al.
In addition to those using an O ₂ thin film, those using an Au thin film [G. Dittmer: “Thin Solid Fi
lms ", 9, 317 (1972)] and In ₂ O ₃ / S
nO ₂ thin film [M. Hartwell and
C. G. FIG. Fonstad: "IEEE Trans.
ED Conf. , 519 (1975)] and carbon thin films [Hiraki Araki et al .: Vacuum, Vol. 26, No. 1
No. 22, 22 (1983)].

As a typical example of the element structure of these surface conduction electron-emitting devices, FIG. Hartwe
3 shows a plan view of the device by Il et al. In the figure, 30
Reference numeral 01 is a substrate, and 3004 is a conductive thin film made of a metal oxide formed by sputtering. The conductive thin film 3004 is formed in an H-shaped plane shape as shown. An electron emission portion 3005 is formed by performing an energization process called energization forming described later on the conductive thin film 3004. The interval L in the figure is 0.5-1 [mm], and W is
It is set at 0.1 [mm]. In addition, for convenience of illustration, the electron emitting portion 3005 is shown in a rectangular shape at the center of the conductive thin film 3004, but this is a schematic one, and the position and shape of the actual electron emitting portion are faithfully represented. Not necessarily.

[0006] M. In the above-described surface conduction electron-emitting device including the device by Hartwell et al., The electron-emitting portion 3005 is formed by subjecting the conductive thin film 3004 to an energization process called energization forming before electron emission.
It was common to form That is, the energization forming energizes by applying a constant DC voltage or a DC voltage boosting at a very slow rate of, for example, about 1 V / min to both ends of the conductive thin film 3004,
That is, the conductive thin film 3004 is locally destroyed, deformed, or altered to form the electron-electron emission portion 3005 having a high electrical resistance. Note that a crack is generated in a part of the conductive thin film 3004 that is locally broken, deformed, or altered. When an appropriate voltage is applied to the conductive thin film 3004 after the energization forming, electron emission is performed in the vicinity of the crack. An example of the FE type is, for example, the W. P. Dyke & W. W. Dola
n, "Field emission", Advance
e in Electron Physics, 8, 89
(1956), or alternatively, C.I. A. Spindt,
"Physical properties of t
hin-film field emission c
athodes with mollybdenium
cones ", J. Appl. Phys., 47, 52.
48 (1976) and the like are known.

As a typical example of the FE type element structure, FIG. A. 1 shows a cross-sectional view of a device by Spindt et al. In the figure, reference numeral 3010 denotes a substrate, and 3011
Is an emitter wiring made of a conductive material, 3012 is an emitter cone, 3013 is an insulating layer, and 3014 is a gate electrode. This device comprises an emitter cone 3012 and a gate electrode 3
By applying an appropriate voltage during 014, field emission is caused from the tip of the emitter cone 3012. In addition, as another element structure of the FE type, as shown in FIG.
There is also an example in which an emitter and a gate electrode are arranged on a substrate almost in parallel with the substrate plane instead of the laminated structure as described above.

As an example of the MIM type, for example,
C. A. Mead, "Operation of tu
nnel-emission Devices, J. et al. A
ppl. Phys. , 32, 646 (1961). FIG. 2 shows a typical example of an MIM type device configuration.
0 is shown. This figure is a cross-sectional view.
Is a substrate, 3021 is a lower electrode made of metal, 3022 is a thin insulating layer having a thickness of about 100 Å, 302
Reference numeral 3 denotes an upper electrode made of a metal having a thickness of about 80 to 300 angstroms. In the MIM type, the upper electrode 302
By applying an appropriate voltage between the third electrode 301 and the lower electrode 3021, electrons are emitted from the surface of the upper electrode 3023.

The above-mentioned cold cathode device can obtain electrons at a lower temperature than the hot cathode device, and therefore does not require a heater for heating. Therefore, the structure is simpler than that of the hot cathode element, and a fine element can be produced. Also,
Even if a large number of elements are arranged on a substrate at a high density, problems such as thermal melting of the substrate hardly occur. Further, unlike the hot cathode element, which has a low response speed for operating by heating the heater, the cold cathode element has an advantage of a high response speed. Therefore, research for applying the cold cathode device has been actively conducted.

For example, the surface conduction electron-emitting device has an advantage that a large number of devices can be formed over a large area because it has a particularly simple structure and is easy to manufacture among cold cathode devices. Therefore, for example, Japanese Patent Application Laid-Open No.
As disclosed in JP-A-332-332, a method for arranging and driving a large number of elements has been studied.

As for the application of the surface conduction electron-emitting device, for example, an image forming apparatus such as an image display device and an image recording device, and a charged beam source have been studied.

In particular, as an application to an image display device, as disclosed in, for example, USP 5,066,883 by the present applicant, Japanese Patent Laid-Open No. 2-257551 and Japanese Patent Laid-Open No. 4-28137, a surface is used. An image display device using a combination of a conduction type emission element and a phosphor that emits light when irradiated with an electron beam has been studied. An image display device using a combination of a surface conduction electron-emitting device and a phosphor is expected to have better characteristics than other conventional image display devices. For example, compared with the liquid crystal display devices that have become widespread in recent years, it can be said that it is superior in that it does not require a backlight because it is a self-luminous type and has a wide viewing angle.

A method for driving a large number of FE types is disclosed in, for example, USP 4,904,8 by the present applicant.
95. Further, as an example in which the FE type is applied to an image display device, for example, R.I. The flat panel display reported by Meyer et al. Is known. [R. Mey
er: “Recent Development on
Microtips Display at LET
I ", Tech. Digest of 4th In
t. Vacuum Microele-ctronic
s Conf. , Nagahama, pp .; 6-9 (1
991)]

An example in which a large number of MIM types are arranged and applied to an image display device is disclosed in, for example, Japanese Patent Application Laid-Open No.
No. 5,557,838.

[0015]

SUMMARY OF THE INVENTION The present inventors have developed various materials, including those described in the above-mentioned prior art.
We have tried cold cathode devices with manufacturing method and structure. Furthermore, research has been conducted on a multi-electron beam source in which a large number of cold cathode devices are arranged, and on an image display device using the multi-electron beam source.

The inventors have tried a multi-electron beam source by an electrical wiring method shown in FIG. 21, for example. That is, it is a multi-electron beam source in which a large number of cold cathode devices are two-dimensionally arranged and these devices are wired in a matrix as shown.

In the figure, 4001 schematically shows a cold cathode element, 4002 is a row-direction wiring which is a scanning wiring, and 40
Reference numeral 03 is a column direction wiring which is a data wiring. The row wiring 4002 and the column wiring 4003 actually have a finite electric resistance, but they are shown as wiring resistances 4004 and 4005 in the drawing. The above-described wiring method is called simple matrix wiring.

Although a 6 × 6 matrix is shown for convenience of illustration, the scale of the matrix is not limited to this. For example, in the case of a multi-electron beam source for an image display device, a desired image is displayed. The elements are arranged and wired in a quantity sufficient for displaying.

In a multi-electron beam source in which cold cathode elements are wired in a simple matrix, in order to output a desired electron beam, row-direction wiring 4002 and column-direction wiring 400
3 is applied with an appropriate electric signal. For example, to drive one row of the cold cathode devices in the matrix, a selection voltage Vs is applied to the row direction wiring 4002 of the selected row,
At the same time, the non-selection voltage Vns is applied to the row direction wiring 4002 of the non-selected row. In synchronization with this, column direction wiring 4003
A drive voltage Ve for outputting an electron beam is applied to. According to this method, wiring resistances 4004 and 4004
If the voltage drop due to 5 is ignored, the voltage of Ve-Vs is applied to the cold cathode elements of the selected row, and the voltage of Ve-Vns is applied to the cold cathode elements of the non-selected rows. V
If e, Vs, and Vns are set to voltages of appropriate magnitudes, an electron beam of a desired intensity should be output only from the cold cathode elements in the selected row, and a different drive voltage Ve is applied to each of the column wirings. If applied, each of the elements in the selected row should output a different intensity electron beam.

If the length of time for applying the drive voltage Ve is changed, the length of time for which the electron beam is output should be changed.

Therefore, a multi-electron beam source in which cold cathode devices are arranged in a simple matrix has various applications. For example, if an electric signal corresponding to image information is appropriately applied, it is suitable as an electron source for an image display device. Can be used.

Usually, the image display device is provided with a brightness adjusting mechanism for making the screen brighter or darker according to the preference of the operator and the difference in ambient light. When the brightness adjusting mechanism is added to the image display device using the cold cathode device as an electron beam source, the brightness is adjusted as follows. FIG. 2 is a perspective view of the display panel. When the electron-emitting device and the phosphor are arranged as shown in FIG. 2, the brightness of the image forming apparatus is determined by the amount of electron emission from the electron-emitting device or the energy of the electron when hitting the phosphor, and thus the electron emission The brightness was adjusted by changing the amount or the energy of electrons hitting the phosphor. That is, the voltage applied to the electron-emitting device or the voltage applied to the phosphor is changed.

When such a brightness adjusting mechanism is provided,
The following problems have occurred. For example, when the brightness is reduced to make it darker, the brightness when the voltage applied to the electron-emitting device is decreased is certainly reduced, but the position where the electron beam hits the phosphor moves with the change in voltage, and the phosphor of the desired color is not hit. There was a color shift due to hitting the adjacent phosphor or hitting a black stripe, and the brightness dropped more than the desired adjustment amount, resulting in a step difference in the adjusted brightness. The same was true when the voltage applied to the phosphor was changed.

Therefore, it is an object of the present invention to solve the above problems and provide an image forming apparatus that does not cause the deviation of the orbit of an electron beam even when the brightness is adjusted, a driving method thereof and a driving circuit.

[0025]

Means for Solving the Problems In order to solve the above-mentioned problems, the present inventors have made intensive efforts and, as a result, have obtained the following invention. That is, the drive circuit of the present invention drives an image forming apparatus having a multi-electron beam source in which a plurality of electron-emitting devices are arranged in a matrix and a target located above the multi-electron beam source and irradiating electrons. In the circuit
It is characterized in that it has means for simultaneously adjusting the voltage applied to the electron-emitting device and the voltage applied to the phosphor.
At this time, in the multi-electron beam source, the plurality of electron-emitting devices may be arranged in a matrix by a plurality of data wirings and a plurality of scanning wirings. Also, the target is
It is said to have a phosphor that emits light when excited by electrons. The present invention also includes a multi-electron beam source in which a plurality of electron-emitting devices are arranged in a matrix, an electron irradiation target located above the multi-electron beam source, and an image forming apparatus having the drive circuit described above. To do. The present invention also includes the invention of a driving method of the image forming apparatus. That is,
An image forming apparatus driving method according to the present invention includes an image forming apparatus having a multi electron beam source in which a plurality of electron emitting elements are arranged in a matrix, and a target located above the multi electron beam source and emitting electrons. In the above driving method, the voltage applied to the electron-emitting device and the voltage applied to the phosphor are adjusted at the same time.

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION As a result of intensive studies by the present inventors,
The cause of the above problems was found. In these electron-emitting devices, the electron beam emitted from the electron-emitting portion 23 generally has an initial velocity component in the direction from the negative electrode 22 to the positive electrode 21. Therefore, the electron beam does not travel in the vertical direction. Furthermore, since the positive electrode 21 and the negative electrode 22 are lined up on the substrate plane, the electron distribution generated in the information space of the electron emitting unit 23 when a drive voltage is applied passes through the electron emitting unit 23 and is perpendicular to the substrate plane. The distribution is asymmetric with respect to. FIG. 11 shows the trajectory of a single element electron beam,
(A) is a sectional view, and (b) is a plan view. That is, FIG.
1 (a) has an asymmetric distribution with respect to the alternate long and short dash line. FIG.
1 (a) shows the potential distribution between the electron-emitting device and the target 24 by a dotted line. As shown in the figure, the equipotential surface is almost parallel to the substrate plane in the vicinity of the target 24, but is inclined in the vicinity of the electron-emitting device due to the influence of the drive voltage Vf [V]. Therefore, the electron beam emitted from the electron emitting portion 23 receives a force in the Z direction due to the tilt potential while flying in the space, and at the same time, receives a force in the X direction as well, and the trajectory thereof is a curved line as shown in the figure. Draw.

For the above-mentioned two reasons, the position where the electron beam irradiates the target 24 is displaced from the position vertically above the electron emitting portion by a distance Lef in the X direction. (2) of FIG. 3 is a plan view of the target 24 as seen from above, and 25 in the drawing schematically shows the electron beam irradiation position on the lower surface of the target (note that the target 24 is shown in FIG.
(1) is a sectional view taken along the alternate long and short dash line JJ 'in (2)). Therefore, in order to generalize and represent how the irradiation position of the electron beam on the target deviates from the position vertically above the electron emission portion, the direction and distance of the deviation are expressed using the vector Ef for convenience. First, it can be said that the direction of the vector Ef is equal to the direction in which the negative electrode of the electron-emitting device and the positive electrode of the electron-emitting portion are arranged side by side on the plane of the substrate. For example, in the case of FIG. 11, the substrate 20
Since the negative electrode 22, the electron emitting portion 23, and the positive electrode 21 of the electron-emitting device are arranged in this order along the X direction, the vector E
f has the same direction as the X direction. For the sake of convenience of illustrating the direction in which the electron-emitting device is formed on the substrate plane and the direction of the vector Ef, these will be schematically represented by the method illustrated in FIG. FIG. 12 shows an electron-emitting device I
In this example, the negative electrode, the electron emitting portion, and the positive electrode are formed side by side along the X direction on the plane of the substrate.

The magnitude of the vector Ef (that is, L
ef) is determined depending on the distance Lh between the electron-emitting device and the target, the drive re-pressure Vf of the electron-emitting device, the potential Va of the target, the type and shape of the electron-emitting device, and the like. It can be calculated by the formula 1).

[0029]

[Outside 1] Where Lh [m] is the distance between the electron-emitting device and the target, Vf is the drive voltage applied to the electron-emitting device, Va is the voltage applied to the target, and K is a constant determined by the type and shape of the electron-emitting device. When the approximate numerical value is calculated by the equation), if the type or shape of the electron-emitting device used is unknown, K = 1 is substituted. When the type and shape of the electron-emitting device are known, the constant K of the electron-emitting device is determined by experiment or computer simulation. Further, in order to obtain Lef with higher accuracy, it is desirable to use K as a function of Vf instead of a constant, but a constant is often sufficient for the accuracy required when designing an image display device. .

When Vf is changed linearly with Vf / Va kept constant, the amount of electron emission increases exponentially with respect to the drive voltage Vf applied to the device. The energy obtained by the emitted electrons is proportional to the voltage (Va) applied to the target, and the obtained luminance is as shown in FIG.
Therefore, during the brightness adjustment, the brightness is controlled so that the brightness changes in proportion to the adjustment operation amount. As a result, even if the brightness adjustment mechanism is provided, there is no color shift and the brightness can be adjusted accurately according to the sense of the operator.

[0031] (1) In formula, since the positional deviation of the electron beam as shown is proportional to (Vf / Va) ^1/2, Keeping In brightness adjustment of (Vf / Va) ^1/2 constant The electron beam is not displaced. At this time, since (Vf / Va) ^1/2 is not proportional to the brightness as described in the section of the prior art, the amount of change with respect to the adjustment amount is determined and controlled so that the brightness changes in proportion to the adjustment operation. . As described above, the electron-emitting device used in the present invention includes the positive electrode, the negative electrode, and the electron-emitting portion as the constituent members, and these members are formed on the plane of the substrate (note that
An element in which a part of the negative electrode also serves as the electron emitting portion may be used). Examples of materials that satisfy such requirements include surface conduction electron-emitting devices and horizontal field emission devices. Hereinafter, the surface conduction electron-emitting device and the lateral field emission device will be described in this order. The surface conduction electron-emitting device includes, for example, the conventional embodiment shown in FIG. 1 and a mode in which fine particles are provided in the vicinity of the electron emitting portion. Regarding the former, various materials are already known as already described in the section of the prior art, but all of them are suitable as the electron-emitting device used in the present invention. Regarding the latter, materials, configurations, manufacturing methods and the like will be described in detail in Examples described later, but all are suitable as an electron-emitting device used in the present invention. That is, when a surface conduction electron-emitting device is used in carrying out the present invention, the material, structure, manufacturing method, etc. of the device are not particularly limited.

Then, regarding the surface conduction electron-emitting device,
The vector Ef indicating the direction in which the electron beam is deflected has the direction shown in FIG. In the figure, (a) is a cross-sectional view and (b) is a plan view. In the figure, 40 is a substrate, 41 is a positive electrode, 42 is a negative electrode, 43 is an electron emitting portion, and VF is for applying a driving voltage to the device. Power. Next, the horizontal field emission device refers to a field emission device in which a negative electrode, an electron emission portion, and a positive electrode are arranged in parallel along the plane of the substrate. For example, the device of FIG. 19 is provided in the vertical direction with respect to the plane of the substrate in the form of a negative electrode: an electron emitting portion and a positive electrode, and thus is not included in the horizontal category.
The element illustrated in (b) is included in the horizontal category. FIG.
Is a perspective view showing an example in which a typical horizontal electron-emitting device is formed along the X direction on the plane of the substrate. In the figure, 50 is a substrate, 51 is a positive electrode, 52 is a negative electrode, and 53 is an electron emitting portion. Is. The horizontal electron-emitting device has various shapes other than those illustrated in FIG.
As described with reference to, the electron beam trajectory deflected from the vertical direction is suitable as the element used in the configuration of the present invention. Therefore, for example, the configuration of FIG. 14 may be provided with a modulation electrode for adjusting the intensity of the electron beam. Further, in the electron emission portion 53, a part of the negative electrode 52 may also serve as this, or a member added on the negative electrode. The material used for the electron emission portion of the horizontal field emission device may be, for example, a refractory metal or diamond, but is not limited to this as long as it is a material that emits electrons satisfactorily.

Regarding the horizontal electron-emitting device,
The vector Ef indicating the direction in which the electron beam is deflected has the direction shown in FIG. In the figure, (a) is a cross-sectional view and (b) is a plan view. In the figure, 50 is a substrate, 51 is a positive electrode, 52 is a negative electrode, 53 is an electron emitting portion, and VF is for applying a drive voltage to the device. Power. Although the electron-emitting device suitable for use in the present invention has been described above, the surface conduction electron-emitting device is used in the display device of the embodiment. The image forming apparatus of the present invention can be used not only for an apparatus for displaying an image by fluorescent display but also for an apparatus for electron beam drawing on a semiconductor.

[0034]

【Example】

(Embodiment 1) An embodiment of the image forming apparatus of the present invention will be described below. The configuration of the image forming apparatus including the surface conduction type element of the embodiment will be described with reference to FIG. In FIG. 1, the display panel 101 described above includes terminals Dx1 to Dxm and Dy1.
Through Dyn are connected to an external circuit. Among them, the terminals Dxl to Dxnn are for sequentially driving the multi-electron beam sources provided in the panel described above, that is, the surface conduction electron-emitting device groups arranged in a matrix of M rows and N columns row by row. A scanning signal is applied. On the other hand, to the terminals Dy1 to Dyn, a modulation signal for controlling the output electron beam of each element of the surface conduction electron-emitting device in one row selected by the scanning signal is applied.

The control circuit 103 has a function of matching the operation timing of each part so that an appropriate display is performed based on an image signal input from the outside. The image signal input from the outside may be, for example, an NTSC signal in which image data and a synchronizing signal are combined, or both may be separated in advance. In the present embodiment, the latter case will be described. (It should be noted that the former image signal can be handled in the same manner as this embodiment by providing a well-known sync separation circuit to separate the image data and the sync signal). That is, the control circuit 103 generates control signals Tscan and Tmry for each unit based on the synchronization signal Tsync input from the outside.
Note that the synchronization signal generally includes a vertical synchronization signal and a horizontal synchronization signal, but is set to Tsync for simplification of description.

On the other hand, image data (luminance data) input from the outside is input to the shift register 104. The shift register 104 serially / sequentially inputs the image data serially input in time series.
It is for parallel conversion and operates based on a control signal (shift clock) Tsft input from the control circuit 103. The data for one line of the image converted into the parallel signal (corresponding to the drive data for the N elements of the electron-emitting device) is output to the latch circuit 105 as a parallel signal of ldl to ldn.

The latch circuit 105 is a memory circuit for storing the data for one line of the image for a required time, and the latch circuit 105 receives the data according to the control signal Tmry sent from the control circuit 103.
Store dl to ldn at the same time. The stored data is
It is output to the pulse width modulation circuit 106 as l'dl to l'dn. The pulse width modulation circuit 106 outputs a voltage signal whose pulse width is modulated with a constant amplitude according to the image data l′ dl to l′ dn as l ″ dl to l ″ ″ dn. More specifically, a voltage pulse having a wider pulse width is output as the brightness level of the image data is higher. For example, a voltage pulse having a maximum brightness of 30 μsec and a minimum brightness of 0.12 μsec is output. is there.
The output signals l ″ dl to l ″ dn are applied to the terminals Dyl to Dyn of the display panel 101. The drive voltage applying means 108 for giving the amplitude of the voltage pulse at this time and the scanning circuit 10
The brightness adjustment circuit 107 outputs an instruction of the output value to 2. The brightness adjustment circuit 107 changes Vf and Va while keeping the ratio of the acceleration voltage Va applied to the high voltage terminal on the face plate constant, though not shown as the amplitude Vf of the voltage pulse according to the instruction signal input from the external adjustment terminal. The instruction to output is output. In order to change the luminance at the time of light emission linearly with respect to the instruction signal input at this time, the instruction signal is converted using the conversion table obtained by inversely converting the data of the luminance conversion accompanying the change of Vf and Va shown in FIG. Converted to Vf and V
Determine the output voltage of a. Next, the scanning circuit 102 will be described. The scanning circuit has M switching elements inside, and each switching element is a control circuit 10.
On the basis of the control signal Tscan generated by the signal No. 3, the inverted output of the drive voltage applying means 108 is connected to the wiring terminal of the electron-emitting device column which is being scanned, and the 0 [v] terminal is connected to the terminal of the electron-emitting device column which is not being scanned. To do. Therefore, the voltage Vf applied to the element
On the other hand, the drive voltage applying unit 108 outputs Vf / 2, so that the desired Vf is applied to the element. Further, each switching element can be easily configured by a switching element such as FET. With the above configuration, only the elements connected to the row selected by the scanning circuit 102 emit electrons only for a period corresponding to each supplied pulse width and voltage value, and the emitted electrons emitted from each element are applied with an acceleration voltage. The phosphor is accelerated by the output voltage of the means 109 and always reaches the same position of the phosphor on the face plate, and the phosphor emits light. The scanning circuit 102 sequentially scans selected rows to form a two-dimensional image.

(Structure and Manufacturing Method of Display Panel) Next, the structure and manufacturing method of the display panel of the image display device to which the present invention is applied will be described with reference to specific examples.

The display panel will be described with reference again to the perspective view of the display panel shown in FIG. 2 with a part of the panel cut away to show the internal structure. In the figure, 1005 is a rear plate, 1006 is a side wall, 1007 is a face plate, and 1005 to 1007 form an airtight container for maintaining the inside of the display panel in a vacuum. When assembling an airtight container, it is necessary to seal the joints of each member in order to maintain sufficient strength and airtightness.For example, apply frit glass to the joints, and in the atmosphere or nitrogen atmosphere, Sealing was achieved by firing at 400-500 degrees for 10 minutes or more. A method of evacuating the inside of the airtight container to a vacuum will be described later.

The rear plate 1005 has a substrate 1001.
Is fixed, but the cold cathode device 1002 is provided on the substrate.
Are formed by N × M. (N and M are positive integers of 2 or more, and are appropriately set according to the target number of surface pixels. For example, in a display device intended to display a high-definition television, N = 3000, M It is desirable to set a number equal to or more than 1000. In this embodiment,
N = 3072 and M = 1024. The N × M cold cathode elements are simply matrix-wired by M row-direction wirings 1003 and N column-direction wirings 1004.
The portion constituted by 1001 to 1004 is called a multi-electron beam source. The manufacturing method and structure of the multi-electron beam source will be described later in detail. In this embodiment, the substrate 1001 of the multi-electron beam source is fixed to the rear plate 1005 of the airtight container. However, when the substrate 1001 of the multi-electron beam source has sufficient strength, the airtight container The multi-electron beam source substrate 1001 itself may be used as the rear plate of FIG. A fluorescent film 1008 is formed on the lower surface of the face plate 1007. Since this embodiment is a color display device, phosphors of three primary colors of red, green, and blue used in the field of CRT are separately applied to a portion of the fluorescent film 1008. The phosphor of each color is, for example, as shown in FIG.
As shown in FIG. 3, the black conductor 1010 is provided separately between stripes of the phosphor, and the black conductor 1010 is provided between the stripes of the phosphor.
The purpose of providing the black conductor 1010 is to prevent the display color from deviating even if the electron beam irradiation position is slightly deviated, and to prevent the reflection of external light to prevent the display contrast from deteriorating. This is to prevent the fluorescent film from being charged up by the electron beam. Black conductor 1010
Although graphite was used as the main component for the above, other materials may be used as long as they are suitable for the above purpose. Also,
The method of separately coating the phosphors of the three primary colors is not limited to the stripe-shaped arrangement shown in FIG. 3A, but may be a delta arrangement as shown in FIG. 3B or an arrangement other than that. It may be. When a monochrome display panel is created, a monochromatic phosphor material is used as the phosphor film 1008.
The black conductive material does not necessarily have to be used.

On the rear plate side surface of the fluorescent film 1008, a metal back 1009 known in the field of CRT is used.
Is provided. The purpose of providing the metal back 1009 is
A part of the light emitted from the fluorescent film 1008 is specularly reflected to improve the light utilization rate, or the fluorescent film 1008
8 to protect it, to act as an electrode for applying an electron beam acceleration voltage, and to act as a conductive path for excited electrons of the fluorescent film 1008. The metal back 1009 was formed by forming a fluorescent film 1008 on the face plate substrate 1007, smoothing the surface of the fluorescent film, and vacuum-depositing AI on the surface.
The metal back 1009 is not used when a low voltage fluorescent material is used for the fluorescent film 1008. Although not used in this embodiment, the face plate substrate 10 is used for the purpose of applying an acceleration voltage and improving the conductivity of the fluorescent film.
A transparent electrode made of, for example, ITO may be provided between 07 and the fluorescent film 1008.

Further, Dx1 to Dxm and Dy1 to Dy
Reference symbols n and Hv are terminals for electrical connection having an airtight structure provided to electrically connect the display panel and an electric circuit (not shown). Dx1 to Dxm are electrically connected to the row direction wiring 1003 of the multi electron beam source, Dy1 to Dyn are electrically connected to the column direction wiring 1004 of the multi electron beam source, and Hv is electrically connected to the metal back 1009 of the face plate.

To evacuate the inside of the airtight container to a vacuum, after assembling the airtight container, an exhaust pipe (not shown) and a vacuum pump are connected, and the inside of the airtight container is reduced to 10 −7 [T].
orr]. Then, the exhaust pipe is sealed, but in order to maintain the degree of vacuum in the airtight container, a getter film (not shown) is formed at a predetermined position in the airtight container immediately before or after the sealing. The getter film is, for example, a film formed by heating a getter material containing Ba as a main component by heating with a heater or high-frequency heating and depositing the getter material.
0 minus 5 or 1 x 10 minus 7 [Tor
The vacuum degree of r] is maintained.

The basic structure and manufacturing method of the display panel of the embodiment of the present invention have been described above.

Next, a method of manufacturing the multi-electron beam source used in the display panel of the above embodiment will be described. The material, shape, and manufacturing method of the cold cathode device are not limited as long as the multi-electron beam source used for the image display device of the present invention is an electron source in which cold cathode devices are arranged in a simple matrix. Therefore, for example, the surface conduction electron-emitting device, the FE type, or the M
A cold cathode device such as an IM type can be used. However, in a situation where a display device having a large display screen and an inexpensive display device is required, among these cold cathode devices, a surface conduction type emission device is particularly preferable. That is, in the FE type, since the relative position and shape of the emitter cone and the gate electrode greatly affect the electron emission characteristics, extremely high-precision manufacturing technology is required, but this achieves a large area and a reduction in manufacturing cost. Is a disadvantageous factor. Further, in the MIM type, it is necessary to make the thicknesses of the insulating layer and the upper electrode thinner and uniform, which is also a disadvantageous factor in achieving a large area and a reduction in manufacturing cost. On the other hand, since the surface conduction electron-emitting device has a relatively simple manufacturing method, it is easy to increase the area and reduce the manufacturing cost. In addition, the inventors have found that among the surface conduction electron-emitting devices, those in which the electron-emitting portion or its peripheral portion is formed of a fine particle film have particularly excellent electron-emitting characteristics and can be easily manufactured. Therefore, it can be said that it is most suitable for use in a multi-electron beam source of a high-luminance, large-screen image display device. Therefore, in the display panel of the above embodiment, the surface conduction electron-emitting device in which the electron emitting portion or its peripheral portion is formed of the fine particle film is used. Therefore, the basic configuration, manufacturing method and characteristics of a suitable surface conduction electron-emitting device will be described first, and then the structure of a multi-electron beam source in which many devices are arranged in a simple matrix will be described.

(Plane Type Surface Conduction Type Emitting Element) The element structure and manufacturing method of the plane type surface conduction type emitting element will be described. FIG. 4 is a plan view (a) and a cross-sectional view (b) for explaining the configuration of a planar surface conduction electron-emitting device. In the figure, 1101 is a substrate, 1102 and 1103 are element electrodes, 1104 is a conductive thin film, 1105 is an electron emission portion formed by an energization forming process, and 1113 is a thin film formed by an energization activation process. As the substrate 1101, for example, various glass substrates such as quartz glass and soda lime glass, various ceramic substrates such as alumina, or the above-mentioned various substrates, for example, S
A substrate in which insulating layers made of iO ₂ are stacked can be used. The device electrodes 1102 and 1103 provided on the substrate 1101 so as to face each other in parallel with the substrate surface are
It is made of a conductive material. For example, Ni, Cr, Au, Mo, W, Pt, Ti, Cu,
A material such as Pd, Ag or the like, an alloy of these metals, a metal oxide such as In ₂ O ₃ —SnO ₂ or a semiconductor such as polysilicon may be appropriately selected and used. Good. The electrodes can be easily formed by using a combination of film forming technology such as vacuum deposition and patterning technology such as photolithography and etching, but other methods (for example, printing technology) can be used to form the electrodes. But it doesn't matter. The shapes of the device electrodes 1102 and 1103 are appropriately designed according to the application purpose of the electron-emitting device. Generally, the electrode interval L is designed by selecting an appropriate value from the range of several hundred angstroms to several hundreds of micrometers. Among them, it is preferable to apply it to a display device, and preferably several tens of micrometers to several tens of micrometers. Is the range. Further, the thickness d of the device electrode is usually selected from an appropriate value within the range of several hundred angstroms to several micrometers. A fine particle film is used for the conductive thin film 1104. The fine particle film described here refers to a film including a large number of fine particles as constituent elements (including an island-shaped aggregate). When the fine particle film is microscopically examined, usually, a structure in which the fine particles are arranged apart from each other, a structure in which the fine particles are adjacent to each other, or a structure in which the fine particles overlap each other is observed.

The particle diameter of the fine particles used in the fine particle film is in the range of several angstroms to several thousand angstroms, but the range of 10 angstroms to 200 angstroms is particularly preferable. Further, the thickness of the fine particle film is appropriately set in consideration of various conditions described below. That is, the device electrode 11
02, or 1103, conditions necessary for satisfactorily performing energization forming described later, conditions necessary for setting the electric resistance of the fine particle film itself to an appropriate value described later. , And so on. In particular,
The thickness is set within the range of several angstroms to several thousand angstroms, with 10 angstroms to 500 angstroms being particularly preferable. Examples of the material that can be used to form the fine particle film include Pd, Pt, Ru, Ag, Au, Ti, In, and C.
u, Cr, Fe, Zn, Sn, Ta, W, Pb, and other metals, PdO, SnO ₂ , In ₂ O ₃ , P
Oxides such as bO and Sb ₂ O ₃ and HfB
₂ , ZrB ₂ , LaB ₆ , CeB ₆ , YB ₄ , GdB ₄
Such as boride, TiC, ZrC, Hf
Among these are carbides such as C, TaC, SiC and WC, nitrides such as TiN, ZrN and HfN, semiconductors such as Si and Ge, and carbon. Is selected as appropriate.
As described above, the conductive thin film 1104 is formed of a fine particle film, and its sheet resistance value is set to fall within the range of 10 3 to 10 7 [ohm / sq]. The conductive thin film 1104 and the device electrode 1102
Since it is desirable that the and 1103 are electrically connected well, they have a structure in which some of them overlap each other. In the example of FIG. 4, the layers are stacked in the order of the substrate, the device electrode, and the conductive thin film from below,
In some cases, the substrate thin film and the device electrode may be laminated in this order from the bottom. In addition, the electron emission unit 1105
Is a crack-like portion formed in a part of the conductive thin film 1104, and has a higher electrical resistance than the surrounding conductive thin film. The crack is formed by performing a later-described energization forming process on the conductive thin film 1104. Fine particles having a particle diameter of several angstroms to several hundred angstroms may be arranged in the cracks.
Note that it is difficult to accurately and accurately illustrate the actual position and shape of the electron-emitting portion, and therefore, it is schematically illustrated in FIG. The thin film 1113 is a thin film made of carbon or a carbon compound, and covers the electron emitting portion 1105 and its vicinity. The thin film 1113 is formed by performing an energization activation process described later after the energization forming process. The thin film 1113 is any one of single crystal graphite, polycrystalline graphite, and amorphous carbon, or a mixture thereof, and the film thickness is 500 [angstrom] or less, and more preferably 300 [angstrom] or less. preferable. Since it is difficult to accurately illustrate the actual position and shape of the thin film 1113, the thin film 1113 is schematically shown in FIG. In addition, in the plan view (a), an element in which a part of the thin film 1113 is removed is illustrated.

The basic structure of a preferable element has been described above, but the following elements were used in the examples. That is, blue glass is used for the substrate 1101, and the element electrode 1 is used.
Ni thin films were used for 102 and 1103. The thickness d of the device electrode is 1000 [angstrom], and the electrode interval L is 2
[Micrometer]. Pd or PdO is used as the main material of the fine particle film, and the thickness of the fine particle film is about 100.
[Angstrom] and width W was 100 [micrometer].

Next, a method for manufacturing a suitable flat surface conduction electron-emitting device will be described. FIGS. 5 (a) to 5 (d)
FIG. 10 is a cross-sectional view for explaining the manufacturing process of the surface conduction electron-emitting device, and the notation of each member is the same as that in FIG.

1) First, as shown in FIG. 5A, device electrodes 1102 and 1103 are formed on a substrate 1101. In formation, the substrate 1101 is sufficiently washed in advance with a detergent, pure water, and an organic solvent, and then a material for an element electrode is deposited (for example, a vacuum deposition method such as a vapor deposition method or a sputtering method). Technology). After that, the deposited electrode material is patterned using photolithography and etching technology,
A pair of device electrodes (1102 and 1103) shown in (a).
To form

2) Next, a conductive thin film 1104 is formed as shown in FIG. In forming the film, first, an organic metal solution is applied to the substrate (a), dried, heated and baked to form a fine particle film, and then patterned into a predetermined shape by photolithography and etching. Here, the organic metal solution is a solution of an organic noble metal compound whose main element is the material of the fine particles used for the conductive thin film (specifically, Pd was used as the main element in this example. In the example, the dipping method was used as the coating method, but other methods such as a spinner method or a spray method may be used). In addition, as a method of forming a conductive thin film made of a fine particle film, other than the method of applying the organometallic solution used in this embodiment, for example, a vacuum evaporation method, a sputtering method, or a chemical vapor deposition method is used. Sometimes used.

3) Next, as shown in FIG. 7C, the forming power supply 1110 to the device electrodes 1102 and 110 are connected.
3, an appropriate voltage is applied, and an energization forming process is performed to form the electron-emitting portion 1105. The energization forming process is a conductive thin film 1104 made of a fine particle film.
Is a process of applying a current to the device to appropriately destroy, deform, or alter a part of it to change it into a structure suitable for electron emission. Appropriate cracks are formed in the thin film in the portion of the conductive thin film made of the fine particle film that has changed to a structure suitable for electron emission (that is, the electron emitting portion 1105). The electron emission unit 1105
After the formation, the electrical resistance measured between the device electrodes 1102 and 1103 is significantly increased as compared to before the formation. In order to explain the energization method in more detail, FIG.
An example of an appropriate voltage waveform applied from the forming power supply 1110 is shown in FIG. When forming a conductive thin film made of a fine particle film, a pulsed voltage is preferable, and in the case of the present embodiment, a pulse width T as shown in FIG.
One triangular wave pulse was continuously applied at a pulse interval T2. At that time, the peak value Vpf of the triangular wave pulse was sequentially increased. Also, monitor pulses Pm for monitoring the state of formation of the electron-emitting portion 1105 are inserted at appropriate intervals between the triangular-wave pulses, and the current flowing at that time is measured by the ammeter 1.
It was measured at 111. In the embodiment, for example, in a vacuum atmosphere of about 10 <-5> [torr], for example, the pulse width T1 is 1 [millisecond], the pulse interval T2 is 10 [millisecond], and the peak value Vpf is 1 pulse. To 0.1 [V] each. Then, every time 5 pulses of the triangular wave are applied, the monitor pulse Pm
Was inserted. The monitor pulse voltage Vpm is set to 0.1 so as not to adversely affect the forming process.
It was set to [V]. Then, the device electrodes 1102 and 110
Ammeter 1111 when the electric resistance between 3 and 1 becomes 10 6 ohms, that is, when the monitor pulse is applied.
When the current measured in 1 became less than 1 × 10 −7 [A], energization related to the forming process was terminated. The above method is a preferable method for the surface conduction electron-emitting device of the present embodiment. For example, when the design of the surface conduction electron-emitting device such as the material and thickness of the fine particle film or the element electrode spacing L is changed. Therefore, it is desirable to appropriately change the energization conditions accordingly.

4) Next, as shown in FIG. 5D, an appropriate voltage is applied from the activation power supply 1112 between the device electrodes 1102 and 1103 to carry out the energization activation process to emit electrons. Improve characteristics. The energization activation process means the electron emission portion 110 formed by the energization forming process.
5 is a process of energizing 5 under appropriate conditions to deposit carbon or a carbon compound in the vicinity thereof (in the figure, a deposit made of carbon or a carbon compound is schematically shown as the member 1113). Note that by performing the energization activation process, the emission current at the same applied voltage can be typically increased by 100 times or more as compared with before the energization activation process. Specifically, by periodically applying a voltage pulse in a vacuum atmosphere within a range of 10 −4 to 10 −5 [torr], an organic compound existing in the vacuum atmosphere is generated. The carbon or carbon compound to be deposited is deposited. The deposit 1113 is any one of single crystal graphite, polycrystalline graphite, and amorphous carbon, or a mixture thereof, and has a film thickness of 500 [angstroms] or less, more preferably 30.
It is 0 [angstrom] or less. In order to explain the energization method in more detail, FIG.
An example of an appropriate voltage waveform applied from No. 12 is shown. In this embodiment, the energization activation process is performed by periodically applying a rectangular wave of a constant voltage. Specifically, the rectangular wave voltage V
The ac is 14 [V], the pulse width T3 is 1 [millisecond], and the pulse interval T4 is 10 [millisecond]. The above-mentioned energization conditions are preferable conditions for the surface conduction electron-emitting device of this embodiment, and when the design of the surface conduction electron emission device is changed, it is desirable to appropriately change the conditions accordingly. Reference numeral 1114 shown in FIG. 4D is an anode electrode for supplementing the emission current Ie emitted from the surface conduction electron-emitting device, which is a DC high voltage power supply 1115 and an ammeter 111.
6 is connected (when the substrate 1101 is incorporated into the display panel and then the activation process is performed, the fluorescent surface of the display panel is used as the anode electrode 1114). While applying the voltage from the activation power supply 1112, the emission current Ie is measured by the ammeter 1116 to monitor the progress of the energization activation process, and the activation power supply 1112 is monitored.
Control the operation of. An example of the emission current Ie measured by the ammeter 1116 is shown in FIG.
When the application of the pulse voltage starts from 2, the emission current Ie increases with time, but eventually saturates and hardly increases. As described above, when the emission current Ie is almost saturated, the voltage application from the activation power supply 1112 is stopped, and the energization activation process is ended. The above-mentioned energization conditions are preferable conditions for the surface-conduction type electron-emitting device of this embodiment, and when the design of the surface-conduction type electron-emitting device is changed, it is preferable to appropriately change the conditions accordingly.

As described above, the plane type surface conduction electron-emitting device shown in FIG. 5 (e) was manufactured.

(Characteristics of Surface Conduction Emitting Element Used in Display Device) The element structure and manufacturing method of the flat surface conduction electron emitting element have been described above. Next, characteristics of the element used in the display device will be described.

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

First, a certain voltage (this is the threshold voltage Vth
The emission current Ie sharply increases when a voltage of the above magnitude is applied to the element, while the emission current Ie is hardly detected at a voltage lower than the threshold voltage Vth. That is, it is a non-linear element having a clear threshold voltage Vth with respect to the emission current Ie.

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

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

Due to the above-mentioned characteristics, the surface conduction electron-emitting device could be preferably used in a display device. For example, in a display device in which a large number of elements are provided corresponding to pixels of a display screen, if the first characteristic is used, display can be performed by sequentially scanning the display screen. That is,
The driving element has a threshold voltage Vt according to a desired light emission luminance.
h or higher, and a voltage lower than the threshold voltage Vth is applied to the non-selected elements. By sequentially switching the elements to be driven, the display screen can be sequentially scanned and displayed. Further, since the emission brightness can be controlled by utilizing the second characteristic or the third characteristic, it is possible to perform the gradation display.

(Structure of multi-electron beam source in which a large number of elements are wired in a simple matrix) Next, the structure of a multi-electron beam source in which the above surface conduction electron-emitting devices are arranged on a substrate and wired in a simple matrix will be described. FIG. 9 is a plan view of the multi-electron beam source used in the display panel of FIG. Surface conduction electron-emitting devices similar to those shown in FIG. 4 are arranged on the substrate, and these devices are wired in a simple matrix by row-direction wiring electrodes 1003 and column-direction wiring electrodes 1004. Row direction wiring electrode 100
An insulating layer (not shown) is formed between the electrodes at the intersections of 3 and the column-directional wiring electrodes 1004 to maintain electrical insulation. FIG. 10 is a sectional view taken along line AA ′ of FIG.
Shown in The multi-electron source having such a structure includes a row-direction wiring electrode 1003, a column-direction wiring electrode 1004, an interelectrode insulating layer (not shown), a device electrode of a surface conduction electron-emitting device, and a conductive thin film. Was formed, power was supplied to each element via the row-direction wiring electrodes 1003 and the column-direction wiring electrodes 1004 to perform the energization forming process and the energization activation process.

(Embodiment 2) FIG. 17 shows a display panel using the surface conduction electron-emitting device described above as an electron beam source, and image information provided from various image information sources such as television broadcasting. It is a figure for showing an example of a display constituted so that it can display. In the figure, 2100 is a display panel, 2101 is a display panel drive circuit, 2102 is a display controller, 2103 is a multiplexer, 2104 is a decoder, 2105 is an input / output interface circuit, and 2106.
Is a CPU, 2107 is an image generation circuit, 2108 and 2
109 and 2110 are image memory interface circuits, 2111 is an image input interface circuit, 21
Reference numerals 12 and 2113 are TV signal receiving circuits, and 2114 is an input portion (note that when the display device receives a signal including both video information and audio information, such as a television signal, the video signal is naturally displayed. Although the sound is reproduced at the same time as the display, the description of circuits, speakers, etc. relating to reception, separation, reproduction, processing, storage of sound information not directly related to the features of the present invention will be omitted). Less than,
The function of each part will be described along the flow of the image signal. First, the TV signal receiving circuit 2113 is a TV that is transmitted using a wireless transmission system such as radio waves or spatial optical communication.
It is a circuit for receiving an image signal. The TV signal system to be received is not particularly limited. For example, NTS
Various methods such as C method, PAL method and SECAM method may be used. In addition, T including a larger number of scanning lines than these
The V signal (for example, a so-called high-definition TV such as the MUSE system) is a signal source suitable for taking advantage of the display panel suitable for a large area and a large number of pixels. The TV signal received by the TV signal receiving circuit 2113 is output to the decoder 2104. The TV signal receiving circuit 2112 is a circuit for receiving a TV image signal transmitted using a wired transmission system such as a coaxial cable or an optical fiber. As with the TV signal receiving circuit 2113, the type 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 2104. The image input interface circuit 2111 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 2104. The image memory interface circuit 2110 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 2104. The image memory interface circuit 2109 is a circuit for capturing the image signal stored in the video disc, and the captured image signal is output to the decoder 2104. The image memory interface circuit 2108 is a circuit for capturing an image signal from a device that stores still image data, such as a so-called still image disc, and the captured still image data is output to the decoder 2104.
The input / output interface circuit 2105 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 2106 of the display device and the outside.

Further, the image generation circuit 2107 is provided with image data, character / graphic information, or CPU which is externally input through the input / output interface circuit 2105.
A circuit for generating display image data based on the image data and character / graphic information output from 2106.
Inside this circuit, for example, rewritable memory for storing image data and character / graphic information, read-only memory for storing image patterns corresponding to character codes, processor for image processing, etc. And the circuits necessary for image generation are incorporated. The display image data generated by this circuit is output to the decoder 2104, but in some cases, it can be output to an external computer network or printer via the input / output interface circuit 2105. Further, the CPU 2106 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 2103 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 2102 according to the image signal to be displayed, and the display frequency, the scanning method (for example, interlace or non-interface), 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 2107,
Alternatively, the external computer or memory is accessed through the input / output interface circuit 2105 to input image data or character / graphic information. The CPU 21
Of course, 06 may be related to 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, it may be connected to an external computer network through the input / output interface circuit 2105, and work such as numerical counting may be performed in cooperation with an external device. The input unit 2114 is used by the user to input commands, programs, or data to the CPU 2106. For example, in addition to a keyboard and a mouse, various input devices such as a joystick, a bar code reader, and a voice recognition device. It is possible to use. Also, the decoder 21
Reference numeral 04 designates various image signals inputted from the above 2107 to 2113 as three primary color signals or luminance signal I signal, Q signal.
It is a circuit for inverse conversion into a signal. It is to be noted that the decoder 2104 desirably includes an image memory therein, as indicated by a dotted line in FIG. This is for handling a television signal that requires an image memory when performing inverse conversion, such as the MUSE method. Also,
The provision of an image memory facilitates the display of still images, or the image generation circuit 2107 and CPU
2106 in cooperation with the image decimation, interpolation, enlargement, reduction,
This is because there is an advantage that image processing such as composition and editing can be easily performed. Also, the multiplexer 2103 is for appropriately selecting a display image based on the control signal input from the CPU 2106. That is, the multiplexer 2103 is the decoder 21
A desired image signal is selected from the inversely converted image signals input from 04 and output to the drive circuit 2101.
In that case, by switching and selecting an image signal 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 TV. . The display panel controller 2102 is a circuit for controlling the operation of the drive circuit 2101 based on the control signal input from the CPU 2106. First, as a signal related to the basic operation of the display panel, for example, a signal for controlling an operation sequence of a power supply (not shown) for driving the display panel is output to the drive circuit 2101. Further, as a signal relating to the display panel driving method, for example, a signal for controlling the screen display frequency and the scanning method (for example, interlace or non-interlace) is output to the drive circuit 2101. 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 2101. In addition, the driving circuit 2101 includes a display panel 2100.
Is a circuit for generating a drive signal to be applied to, and operates based on an image signal input from the multiplexer 2103 and a control signal input from the display panel controller 2102. The function of each unit has been described above, but with the configuration illustrated in FIG.
In this display device, image information input from various image information sources can be displayed on the display panel 2100. That is, various image signals such as television broadcast are inversely converted by the decoder 2104, appropriately selected by the multiplexer 2103, and input to the drive circuit 2101. On the other hand, the display controller 2102 generates a control signal for controlling the operation of the drive circuit 2101 according to the image signal to be displayed. The driving circuit 2101 applies a driving signal to the display panel 2100 based on the image signal and the control signal. Accordingly, an image is displayed on display panel 2100. These series of operations are performed by the CPU
It is controlled overall by 2106. Further, in the present display device, the image memory built in the decoder 2104, the image generation circuit 2107 and the CPU 2106 are involved, so that not only the one selected from the plurality of image information is displayed but also the selected one is displayed. Image information such as enlargement, reduction, rotation, movement, edge enhancement, thinning, interpolation, color conversion, and aspect ratio conversion of images, as well as compositing, erasing, connecting, swapping, fitting, etc. It is also possible to edit images for the first time.
Further, although the description of the present embodiment has not been particularly mentioned, a dedicated circuit for processing and editing audio information may be provided as in the above-mentioned image processing and image editing. Therefore,
This display device has functions of a display device for television broadcasting, a terminal device for a video conference, an image editing device that handles still images and moving images, a terminal device for a computer, an office terminal device such as a word processor, and a game console. A single unit can be combined, and it has an extremely wide range of applications for industrial or consumer use. It is needless to say that FIG. 17 shows only an example of the configuration of a display device using a display panel having a surface conduction electron-emitting device as an electron beam source, and is not limited to this. For example, of the constituent elements of FIG. 17, circuits relating to functions that are unnecessary for the purpose of use may be omitted. Conversely, additional components may be added depending on the purpose of use. For example, when the present display device is applied to a videophone, it is preferable to add a television camera, an audio microphone, a lighting device, a transmission / reception circuit including a modem, and the like to the components. In this display device, in particular, the display panel using the surface conduction electron-emitting device as the electron beam source can be easily thinned, so that the depth of the entire display device can be reduced. In addition, the display panel using the surface conduction electron-emitting device as the electron beam source is easy to enlarge the screen, has high brightness, and has excellent viewing angle characteristics. It is possible to display well.

[0064]

According to the present invention, the orbit of the electron beam is not deviated due to the brightness adjustment. Therefore, problems such as color shift of the image forming apparatus do not occur.

[Brief description of drawings]

FIG. 1 is a block diagram of an image forming apparatus according to a first exemplary embodiment.

FIG. 2 is a perspective view of a display panel.

FIG. 3 is a phosphor array diagram of a face plate.

FIG. 4 is a plan view (a) and a sectional view (B) of a flat surface conduction electron-emitting device.

FIG. 5 is a diagram showing a manufacturing process of a planar surface conduction electron-emitting device.

FIG. 6 is a time chart showing a forming voltage.

FIG. 7 is a time chart of activation voltage and emission current.

FIG. 8 is a cross-sectional view of a vertical surface conduction electron-emitting device.

FIG. 9 is a plan view of a multi-electron beam substrate.

FIG. 10 is a partial cross-sectional view of a multi-electron beam substrate.

FIG. 11 is a diagram showing a trajectory of an electron beam.

FIG. 12 is a diagram showing the trajectory of an electron beam.

FIG. 13 is a diagram showing a trajectory of an electron beam of the surface conduction electron-emitting device.

FIG. 14 is a diagram showing a horizontal FE.

FIG. 15 is a diagram showing a trajectory of an electron beam of a horizontal FE.

FIG. 16 is a graph showing Vf-Vf / Va characteristics.

FIG. 17 is a block diagram of a multiplex display.

FIG. Hartwell et al. FIG. 1 is a plan view of a conventional surface conduction electron-emitting device disclosed by A.

FIG. 19 is a sectional view of an FE type element.

FIG. 20 is a cross-sectional view of an MIM type element.

FIG. 21 is a schematic diagram of simple matrix wiring.

[Explanation of symbols]

 1, 2, 40, 50 Substrate 2 Electron-emitting device 3 Row direction wiring 4 Column direction wiring 5 Rear plate 6 Side wall 7 Face plate 8 Fluorescent film 9 Metal back 10 Black conductor 11 Striped fluorescent body 21, 41, 51 Positive electrode 22 , 42, 52 Negative electrode 23, 43, 53 Electron emission part 24 Target (phosphor) 25 Electron beam irradiation position 101 Display panel 102 Scanning circuit selection 103 Control circuit 104 Shift register 105 Latch circuit 106 Pulse width conversion circuit 107 Brightness adjusting circuit 108 Driving voltage applying means 109 Accelerating voltage applying means

Claims (5)

[Claims] 1. A drive circuit of an image forming apparatus, comprising: a multi-electron beam source having a plurality of electron-emitting devices arranged in a matrix; and a target located above the multi-electron beam source and irradiating electrons. A drive circuit having means for simultaneously adjusting the voltage applied to the electron-emitting device and the voltage applied to the target. 2. The drive circuit according to claim 1, wherein the multi-electron beam source has a matrix wiring of the plurality of electron-emitting devices with a plurality of data wirings and a plurality of scanning wirings. 3. The drive circuit according to claim 1, wherein the target has a phosphor that excites and emits light when irradiated with electrons. 4. The multi-electron beam source in which a plurality of electron-emitting devices are arranged in a matrix, a target located above the multi-beam source and for irradiating electrons, and the drive according to claim 1. An image forming apparatus having a circuit. 5. A method of driving an image forming apparatus, comprising: a multi-electron beam source having a plurality of electron-emitting devices arranged in a matrix; and a target located above the multi-electron beam source and irradiating electrons. A driving method characterized in that the voltage applied to the electron-emitting device and the voltage applied to the target are simultaneously adjusted.