JPH11176363A - Image display method and apparatus - Google Patents

Abstract

(57) [Problem] To provide an image display method and apparatus capable of displaying an image by faithfully reproducing a predetermined luminance while suppressing a change in a signal level caused by a stray capacitance between adjacent wirings. SOLUTION: The display panel 11 has (m × n) electron-emitting devices, and the electron-emitting devices are connected in a matrix by row wiring and column wiring, and the column wiring is connected to the column wiring according to the luminance of an image signal. When a pulse signal to be applied is generated from the PWM 101 and the generated pulse signal is a display signal, a current from the current source I1 is supplied to the corresponding column wiring by the switch circuit 103, and the pulse signal is a non-display signal. At this time, the switch circuit 103 is switched by the constant current source I2 so that the current flows from the corresponding column wiring in a direction opposite to the direction in which the current flows through the current source I1, and the transistor 100 is turned on. An image is displayed on the display panel 11 by sequentially selecting and driving the row wiring in accordance with the timing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a driving circuit for an image display device, an image display device using the same, and a method for driving them.

[0002]

2. Description of the Related Art In recent years, research and development of thin and large screen display devices have been actively conducted. The present inventor has been conducting research using a cold cathode as an electron source as a thin large-screen display device.

Conventionally, two types of electron-emitting devices, a hot cathode device and a cold cathode device, are known. Among them, as the cold cathode device, 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. .

[0004] As the surface conduction type emission element, for example, M.
I. Elinson, Radio E-ng. Electron Phys., 10, 1290,
(1965) and other examples described later.

[0005] The surface conduction electron-emitting device utilizes a phenomenon in which electron emission occurs when a current flows in a small-area thin film formed on a substrate in parallel with the film surface. Examples of the surface conduction electron-emitting device include a device using an SnO2 thin film by Elinson et al., And a device using an Au thin film [G. Dittmer: “Thin Solid Films”, 9,317 (1)
972)] and those based on In2O3 / SnO2 thin films [M. Hart
well and CG Fonstad: "IEEE Trans. ED Conf."
519 (1975)] and those using carbon thin films [Hisashi Araki
Others: Vacuum, Vol. 26, No. 1, 22 (1983)].

FIG. 19 shows a plan view of a device by M. Hartwell et al. As a typical example of the device configuration of these surface conduction electron-emitting devices. In the figure, reference numeral 3001 denotes a substrate, and reference numeral 3004 denotes a conductive thin film made of a metal oxide formed by sputtering. The conductive thin film 3004 is formed in an H-shaped planar shape as shown. An electron emission portion 3005 is formed by applying an energization process called energization forming to be described later to the conductive thin film 3004. The interval L in the figure is 0.5 to 1 [mm], and the width W is
It is set to 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.

In the above-described surface conduction electron-emitting device, such as the device by M. Hartwell et al., Before the electron emission, an electron emission portion 3005 is formed by subjecting the conductive thin film 3004 to an energization process called energization forming. Was common. That is, energization forming is
An electron-emitting portion is formed by energization. For example, a constant DC voltage or a DC voltage that increases at a very slow rate of, for example, about 1 V / min is applied to both ends of the conductive thin film 3004 and energized. And the conductive thin film 30
04 is locally destroyed or deformed or altered,
This is to form the electron-emitting portion 3005 in a state of being electrically high in 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.

The above-mentioned surface conduction electron-emitting device has an advantage that a large number of devices can be formed over a large area because of its simple structure and easy manufacture. Therefore, as disclosed in, for example, Japanese Patent Application Laid-Open No. 64-31332 by the present applicant, a method for arranging and driving a large number of elements has been studied.

As an example of the FE type, for example, WP Dyke
& WW Dolan, “Field emission”, Advance in Ele
ctron Physics, 8, 89 (1956) or CA Spind
t, “Physical properties of thin-film field emissi
on cathodes with molybdeniumcones ”, J. Appl. Phy
s., 47, 5248 (1976).

As a typical example of this FE type device configuration, FIG. 20 shows a cross-sectional view of the device by CA Spindt et al. Described above. In the figure, 3010 is a substrate, 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. As another element configuration of the FE type, 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.

Examples of the MIM type include, for example, C.I.
A. Mead, “Operation of tunnel-emission Devices,
J. Appl. Phys., 32,646 (1961) and the like are known.
FIG. 21 shows a typical example of the MIM type element configuration.
The figure is a cross-sectional view, in which 3020 is a substrate,
3021 is a lower electrode made of metal, 3022 is a thickness of 100
An insulating layer as thin as about Å, and 3023 has a thickness of 8
The upper electrode is made of a metal of about 0 to 300 angstroms. In the MIM type, electrons are emitted from the surface of the upper electrode 3023 by applying an appropriate voltage between the upper electrode 3023 and the lower electrode 3021.

The above-described 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. Further, even when a large number of elements are arranged on a substrate at a high density, problems such as thermal melting of the substrate hardly occur. Also, unlike the response speed is slow because the hot cathode element operates by heating the heater,
In the case of a cold cathode device, there is also an advantage that the response speed is high. For this reason, research for applying the cold cathode device has been actively conducted.

For example, the surface conduction electron-emitting device has the advantage of being able to form a large number of devices over a large area because it has a particularly simple structure and is easy to manufacture among the cold cathode devices. Therefore, for example, Japanese Patent Application Laid-Open No.
As disclosed in Japanese Patent Publication No. 32, a method for arranging and driving a large number of elements has been studied.

With respect to applications of the surface conduction electron-emitting device, for example, image forming apparatuses such as image display apparatuses and image recording apparatuses, and charged beam sources have been studied.

Particularly, as an application to an image display device, for example, as disclosed in US Pat. No. 5,066,883, JP-A-2-257551 and JP-A-4-28137 by the present applicant, surface conduction is disclosed. An image display device using a combination of a mold emission element and a phosphor that emits light by electron irradiation 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 to a liquid crystal display device that has become widespread in recent years, it can be said that it is excellent in that it is a self-luminous type and does not require a backlight and has a wide viewing angle.

A method of arranging and driving a large number of FE elements is disclosed in, for example, US Pat. No. 4,904,89 by the present applicant.
5 is disclosed. Further, as an example of applying the FE type to an image display device, for example, a flat panel display device reported by R. Meyer et al. Is known. [R. Meyer: “Recent D
evelopment on Microtips Display at LETI ”, Tech.Di
gest of 4th Int.Vacuum Microelectronics Conf., Na
gahama, pp. 6-9 (1991)].

An example in which a 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. 5738.

The inventors of the present application have attempted surface conduction type emission devices having various materials, manufacturing methods and structures, including those described in the above-mentioned prior art. Further, research has been conducted on a multi-electron source in which a large number of surface conduction electron-emitting devices are arranged, and on an image display device using the multi-electron source. For example, a multi-electron source based on the electrical wiring method shown in FIG. 22 has been tried. That is, the surface conduction type emission device is
This is a multi-electron source in which a large number of elements are arranged in a dimension, and these elements are wired in a matrix as shown in the figure.

In the figure, 4001 schematically shows a surface conduction electron-emitting device, 4002 shows a row direction wiring, and 4003 shows a column direction wiring. Although the row direction wiring 4002 and the column direction wiring 4003 actually have a finite electric resistance, they are shown as wiring resistances 4004 and 4005 in the figure. The above-described wiring method is called simple matrix wiring. Although a 6 × 6 matrix is shown for convenience of illustration, the size of the matrix is not limited to this. For example, in the case of a multi-electron source for displaying images, a desired image is displayed. Only enough elements are arranged and wired.

In the multi-electron source in which the surface conduction electron-emitting devices are arranged in a simple matrix as described above, an appropriate electric signal is applied to the row wiring 4002 and the column wiring 4003 in order to output a desired electron beam. For example,
In order to drive any one of the surface conduction electron-emitting devices in the matrix, the selection voltage Vs is applied to the row direction wiring 4002 of the selected row, and at the same time, the row direction wiring 40 of the non-selected row is applied.
02 is applied with a non-selection voltage Vns. In synchronization with this, a drive voltage Ve for outputting an electron beam is applied to the column wiring 4003. According to this method, the wiring resistance 40
Neglecting the voltage effects of the elements 04 and 4005, a voltage of (Ve−Vs) is applied to the surface conduction type emission elements of the selected row, and (V) is applied to the surface conduction type emission elements of the non-selected rows.
e-Vns). Where Ve, Vs,
If Vns is set to a voltage of an appropriate magnitude, an electron beam having a desired intensity should be output only from the surface conduction electron-emitting device of the selected row, and a different drive voltage Ve is applied to each of the column-directional wirings. Then, the electron beams of different intensities should be output from each of the elements in the selected row. In addition, since the response speed of the surface conduction electron-emitting device is high,
If the length of time during which the drive voltage Ve is applied is changed, the length of time during which the electron beam is output should be changed.

Hereinafter, the element applied voltage (Ve-V
s) is called Vf.

Further, as another method for obtaining an electron beam from the multi-electron source wired in a simple matrix as described above, a drive current is supplied instead of connecting a voltage source for applying a drive voltage Ve to a column wiring. And a selection voltage Vs in the row direction wiring of the row to be selected.
, And simultaneously applying a non-selection voltage Vns to the row direction wirings of the non-selected rows. This allows
Due to the strong threshold characteristic of the surface conduction electron-emitting device, an electron beam can be obtained only from the device in the selected row.
Here, the current flowing through the electron source is hereinafter referred to as an element current If, and the emitted electron beam current is referred to as an emission current Ie.

Therefore, a multi-electron source having a surface conduction type electron-emitting device arranged in a simple matrix has various applications. For example, if an electric signal corresponding to image information is appropriately applied, the multi-electron source can be used as an electron source for an image display device. It can be suitably used.

[0024]

However, a multi-electron source in which surface conduction electron-emitting devices are arranged in a simple matrix has actually had the following problems.

As described above, a desired beam output can be obtained by applying a drive voltage or a drive current and performing pulse width modulation. However, the beam has a finite length from the drive means to the multi-electron source. A method of applying a drive current or a drive voltage to suppress ringing at the time of pulse application (rising) due to resonance generated due to an inductance component of a wiring, a capacitance component between adjacent wirings, a stray capacitance component, or the like. Is applied, a method of limiting current is often adopted. On the other hand, at the end of the pulse application (fall), switching means should be provided to apply a voltage bias having low impedance in order to quickly discharge the charge accumulated by the stray capacitance and shorten the fall time. There were many. By these means,
Each element is driven while preventing the occurrence of ringing exceeding the rated value of the applied voltage of the multi-electron source.

However, another problem has occurred in the above configuration.

That is, as shown in FIG. 2, when a pulse signal having a different pulse width is applied between two adjacent (or more) wirings, a pulse having a longer width is caused by the capacitance between the wirings. A phenomenon occurs in which the signal level decreases due to the influence of the pulse signal that has fallen earlier, and the effective application amount decreases. Due to such a phenomenon, when the gradation is expressed by the pulse width, an error occurs in the gradation due to the influence of the adjacent wiring. In particular, when a large-screen panel is configured, there is a problem in that the capacitance between wirings increases, and this error in gradation characteristics increases.

The present invention has been made in view of the above conventional example, and an image display capable of displaying an image by faithfully reproducing a predetermined luminance by suppressing a change in a signal level due to a stray capacitance between adjacent wirings. It is an object to provide a method and an apparatus.

It is another object of the present invention to minimize the fluctuation of the signal level on a signal line due to the fall of the signal of an adjacent signal line, thereby making the fluctuation of the luminance of the displayed image inconspicuous. It is to provide a method and an apparatus.

[0030]

In order to achieve the above object, an image display device according to the present invention has the following arrangement.
That is, the plurality of electron-emitting devices are provided, and the plurality of electron-emitting devices are formed by a row wiring commonly connected to each of the plurality of electron-emitting devices and a column wiring provided for each of the m electron-emitting devices. An electron source to which the emission element is connected, signal generation means for generating a signal to be applied to the column wiring according to an image signal, and when the signal generated by the signal generation means is a display signal, the corresponding column wiring Current applying means for flowing the current from the first constant current source to the first current source, and when the signal generated by the signal generating means is a non-display signal, the second constant current source causes And a driving means for driving so as to flow a current in a direction opposite to a direction of the flowing current.

In order to achieve the above object, the image display method of the present invention comprises the following steps. That is, the plurality of electron-emitting devices are provided, and the plurality of electron-emitting devices are formed by a row wiring commonly connected to each of the plurality of electron-emitting devices and a column wiring provided for each of the m electron-emitting devices. An image display method for displaying an image by driving an electron source to which an emission element is connected, wherein the signal generation step includes a step of generating a signal to be applied to the column wiring according to an image signal. A current application step of flowing a current from a first constant current source to a corresponding column wiring when the signal is a display signal, and a corresponding column wiring when the signal generated in the signal generation step becomes a non-display signal. In the applied voltage lowering step of reducing the voltage to a predetermined voltage, and driving the column wiring, which has been lowered to the predetermined voltage in the applied voltage lowering step, in a direction opposite to the direction in which the current flows in the current applying step. Drive Characterized by a step.

[0032]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

(Embodiment 1) FIG. 1 is a block diagram showing a circuit configuration of an image display device according to Embodiment 1 of the present invention, FIG. 3 is a diagram for explaining effects of the circuit of FIG. 1, and FIG. FIG. 2 is a waveform chart showing signal timings of respective parts in FIG.

In FIG. 1, reference numeral 11 denotes a display panel in which a plurality of surface conduction electron-emitting devices having device voltage-emission current characteristics described later are arranged in an m × n matrix. Reference numeral 1 denotes a video input signal terminal for inputting a video signal, 2 denotes an analog signal processing unit, and an A / D conversion unit 3 converts a video luminance signal into a predetermined number of gradations. Performs level clamping, amplitude level adjustment, and band limitation. Reference numeral 4 denotes a synchronization separation unit, which separates synchronization signals (horizontal and vertical synchronization signals, etc.) from an input video signal. Reference numeral 5 denotes a timing generation unit which inputs a synchronization signal output from the synchronization separation unit 4 and supplies necessary timing signals to the A / D unit 3 and various parts.

The A / D section 3 converts the video analog luminance signal into n serial digital signals per one horizontal period and outputs the serial digital signals.
, And is converted to a parallel signal, sent to the one-line memory 7 and stored. Column wiring drive unit 10
A current source I1 for applying a current to the column wiring via the switch circuit 103 when an output pulse signal of a PWM generator 101, which will be described later, according to input luminance data is on, for each column wiring; A common base transistor 100 for applying a DC bias voltage (ground level) limited by the current source I2 through the switch circuit 103 when the data is off, and a signal having a pulse width proportional to the luminance data for switching on and off of the transistors Output PW
An M generator (PWN GEN) 101 is provided. That is, the switch circuit 103 includes a PWM generator (PWN GEN) 10.
When the pulse signal (luminance data) is high, the current from the current source I1 flows through the column wiring, and when the pulse signal goes low, the column wiring is connected to the transistor 1
00 and the transistor 100 is turned on. Here, a diode 102 for clipping the voltage applied to the column wiring to Vm is provided as protection for preventing the voltage applied to the element from exceeding the rated value when the luminance data is at a high level. Note that the potential Vss connected to the current source I2 of the column wiring drive unit 10 may be at the ground level or about several volts. Also Vdd
Is a potential substantially equivalent to the potential Ve in FIG.

The row wiring drive section 9 has a switch circuit 110 for selecting whether to apply a DC voltage bias Vs to the row wiring or to ground the row wiring for each row of the display panel 11.
The connection of these switch circuits 110 is sequentially switched by an output signal from the vertical shift register 8 to sequentially display the display panel 1.
Each line of the display panel 11 is sequentially scanned and driven by applying the DC voltage bias Vs to each row in order. The vertical shift register receives, for example, a horizontal synchronizing signal from the timing generator 5 and outputs a signal so as to sequentially switch and select a row wiring every time the horizontal synchronizing signal is input.

When the pulse signal shown in FIG. 2 is turned off (falling), the driving voltage waveform of the column wiring is switched to the ground level by the transistor 100 with low impedance. As a result, the reduction of the effective voltage due to the stray capacitance between the adjacent row wirings is improved by performing the current limitation as shown in FIG.

Next, the operation of the circuit of FIG. 1 will be described with reference to FIG.

In FIG. 4, reference numeral 401 denotes an analog video signal input to the video signal input terminal 1; 402, an analog-to-digital conversion of the analog video signal to form a column through a horizontal shift register 6 and a one-line memory 7; 2 shows digital data for each line input to the wiring drive unit 10. 4
03 is for one line, that is, n pulse width modulation circuits 10
0 indicates a pulse width modulation signal, and the pulse width of each of these pulse signals is a pulse width corresponding to the luminance of the digital luminance data. Reference numeral 404 denotes an output signal of the vertical shift register 8, and the row wiring is sequentially switched and selected each time a horizontal synchronizing signal is input. Reference numeral 405 denotes a potential applied to each row wiring, and the potential Vs is applied to the row wiring selected by the output signal of the vertical shift register 8.
Is applied.

In this example, the rise time of the pulse is delayed due to the drive by the current source I1, but, for example, up to a certain voltage is driven by the voltage source, and then the current source is activated. Similar effects can be obtained even when the drive signal rise time is made steep.

(Embodiment 2) FIG. 5 is a block diagram showing a circuit configuration of an image display apparatus according to Embodiment 2 of the present invention.
1 are denoted by the same reference numerals, and description thereof will be omitted.

The column wiring drive section 10a includes, for each column wiring, a current source I1 for applying a current when the luminance data (pulse signal) is on, and a DC current limited by a resistor 105 (r) when the luminance data (pulse signal) is off. Apply a bias voltage (ground level)
Alternatively, a switch circuit 104 for switching whether to apply the DC bias Vb is provided. PWM generator (PWMGE
N) 101 further applies a DC bias Vb first in a short period at the beginning of the fall of the pulse signal, and then applies a current-limited ground level bias via a resistor 105. Note that when the current supply from the current source I1 is on, the applied voltage is set to V by the diode 102 as protection to prevent the voltage applied to the column wiring from exceeding the rating.
The same is true for clipping to m.

With such a configuration, the voltage waveform applied to the column wiring rapidly falls to the voltage Vb as shown in FIG. 6, and then has a time constant determined by the current limiting resistor 105 and the stray capacitance of the wiring. Fall slowly based on.
It can be seen from this effect that the decrease in the effective voltage due to crosstalk as shown in FIG. 2 is further reduced, and the decrease in the effective voltage is improved.

Although the configuration of the second embodiment has a greater influence of crosstalk than the first embodiment, the fall time of the luminance data (pulse signal) is shorter than that of the first embodiment. be able to. In particular, in a display panel using a surface conduction electron-emitting device having a steep threshold characteristic in drive voltage-emission luminance (device emission current), which will be described later, even if the voltage width (Ve-Vb) that sharply falls is small, In terms of the displayed luminance, it can sufficiently follow.

The operation of the circuit of FIG. 5 is the same as that of the above-described timing chart of FIG.

<Description of Manufacturing Method and Application of Surface Conduction Emission Element of Present Embodiment> FIG. 7 shows a display panel 1 of the present embodiment.
000 is an external perspective view of the display panel 1000 in which a part of the display panel 1000 is cut away to show the internal structure thereof.

In the figure, 1005 is a rear plate, 1006
Is a side wall, 1007 is a face plate, 1005
1007 form an airtight container for maintaining the inside of the display panel at a vacuum. When assembling this hermetic container, it is necessary to seal the joints of each member to maintain sufficient strength and airtightness.For example, frit glass is applied to the joints, and in the air or in a nitrogen atmosphere, Sealing was achieved by baking at 400 ° C. to 500 ° C. 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
Are fixed, but N × M surface-conduction emission devices 1002 are formed on the substrate 1001 (where N and M are positive integers of 2 or more, and the desired number of display pixels) For example, in a display device for displaying high-definition television, N = 300.
It is desirable to set 0, M = 1000 or more.
In the present embodiment, N = 3072, M = 1024
And). The N × M surface conduction electron-emitting devices 1002
Are M row-directional wirings 1003 and N column-directional wirings 10
04 is a simple matrix wiring. 100
The portion constituted by 1 to 1004 is called a multi-electron source. The manufacturing method and structure of the multi-electron source will be described later in detail.

In this embodiment, the substrate 1001 of the multi-electron source is fixed to the rear plate 1005 of the hermetic container. However, when the substrate 1001 of the multi-electron source has a sufficient strength, The substrate 1001 of the multi-electron source may be used as the rear plate of the airtight container.

On the lower surface of the face plate 1007, a fluorescent film 1008 is formed. Since the display panel 1000 of this embodiment is for color display, phosphors of three primary colors of red (R), green (G), and blue (B) used in the field of CRT are provided on the fluorescent film 1008. It is painted separately. The phosphors of each color are separately applied in stripes as shown in FIG. 8A, for example, and black conductors 1010 are provided between the stripes of the phosphors of each color. The purpose of providing the black conductor 1010 is to prevent the display color from being shifted even if the electron irradiation position is slightly shifted, or to prevent the reflection of external light to prevent the reduction of the display contrast. This is to prevent charge-up of the fluorescent film by electrons. Although graphite is used as a main component for the black conductor 1010, any other material may be used as long as it is suitable for the above purpose.

FIG. 8 shows how to paint the three primary color phosphors.
The arrangement is not limited to the stripe arrangement shown in FIG. 8A, but may be, for example, a delta arrangement as shown in FIG. 8B or another arrangement. Note that when a monochrome display panel is manufactured, a single-color phosphor material may be used for the phosphor film 1008, and a black conductive material is not necessarily used.

A metal back 1009 known in the field of CRTs is provided on the surface of the fluorescent film 1008 on the rear plate side.
Is provided. The purpose of providing the metal back 1009 is to improve the light utilization rate by mirror-reflecting a part of the light emitted from the fluorescent film 1008 so that the fluorescent film 1
008, to act as an electrode for applying an electron accelerating voltage, and to make the fluorescent film 1008 act as a conductive path for the excited electrons. 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 aluminum thereon. Note that when a fluorescent material for low voltage is used for the fluorescent film 1008, the metal back 1009 is not used.

Although not used in the present embodiment,
For the purpose of applying acceleration voltage and improving the conductivity of the fluorescent film,
A transparent electrode made of, for example, ITO may be provided between the face plate substrate 1007 and the fluorescent film 1008.

Dx1 to DxM, Dy1 to DyN, and Hv are electric connection terminals having an airtight structure provided for electrically connecting the display panel 1000 to an electric circuit (not shown). Dx1 to DxM are the row direction wirings 1 of the multi-electron source
003 and Dy1 to DyN are the column wirings 10 of the multi-electron source.
04 and Hv are the metal back 100 of the face plate
9, respectively.

In order to evacuate the inside of the hermetic container to a vacuum, after assembling the hermetic container, an exhaust pipe (not shown) and a vacuum pump are connected, and the inside of the hermetic container is raised to the power of 10 −7 [to
rr]. Thereafter, the exhaust pipe is sealed, but a getter film (not shown) is formed at a predetermined position in the airtight container immediately before or after the sealing in order to maintain the degree of vacuum in the airtight container. The getter film is, for example, a film formed by heating and depositing a getter material containing Ba as a main component by a heater or high-frequency heating, and the inside of the airtight container is 1 × 10−5 or 1 due to the adsorbing action of the getter film. It is maintained at a degree of vacuum of × 10−7 [torr].

As described above, the display panel 1 according to the embodiment of the present invention is described.
000 has been described.

Next, the display panel 100 of this embodiment will be described.
A method for manufacturing the multi-electron source used for the first embodiment will be described.
The multi-electron source used for the image display device of the present embodiment is
There is no limitation on the material, shape, or manufacturing method of the surface conduction electron-emitting device as long as it is an electron source in which the surface conduction electron-emitting devices are arranged in a simple matrix. Therefore, for example, a cold cathode device such as a surface conduction type emission device, an FE type, or an MIM type can be used. However, the present 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 excellent electron-emitting characteristics and can be easily manufactured. Therefore,
It can be said that this is most suitable for use in a multi-electron source of a high-brightness, large-screen image display device. Therefore, in the display panel of the above embodiment, a surface conduction electron-emitting device in which the electron-emitting portion or its peripheral portion is formed of a fine particle film is used. Therefore, the basic structure, manufacturing method and characteristics of a suitable surface conduction electron-emitting device will be described first, and then the structure of a multi-electron source in which a large number of devices are arranged in a simple matrix will be described.

(Suitable Device Configuration and Manufacturing Method of Surface Conduction Emission Device) Representative configurations of a surface conduction electron-emitting device in which an electron-emitting portion or its peripheral portion is formed from a fine particle film include a planar type and a vertical type. Kinds are given.

(Planar surface conduction electron-emitting device) First, the structure and manufacturing method of a plane surface conduction electron-emitting device will be described. FIG. 9 shows a plan view (A) and a cross-sectional view (B) for describing the configuration of a planar surface conduction electron-emitting device. In the figure, 1101 is a substrate, 1102 and 1
103, a device electrode; 1104, a conductive thin film; 1105, an electron-emitting portion formed by an energization forming process;
Reference numeral 13 denotes a thin film formed by the activation process.

As the substrate 1101, for example, various glass substrates such as quartz glass and blue plate glass, various ceramics substrates such as alumina, or an insulating layer made of, for example, SiO 2 is formed on the various substrates described above. A stacked substrate or the like can be used.

The device electrodes 1102 and 1103 provided on the substrate 1101 in parallel with the substrate surface are formed of a conductive material. For example, N
i, Cr, Au, Mo, W, Pt, Ti, Cu, Pd,
Materials may be appropriately selected and used from metals such as Ag and the like, alloys of these metals, metal oxides such as In 2 O 3 —SnO 2, and semiconductors such as polysilicon. The electrodes can be easily formed by using a combination of a film forming technique such as vacuum evaporation and a patterning technique such as photolithography and etching. However, the electrodes can be formed using other methods (for example, printing techniques). I can't wait.

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 usually designed by selecting an appropriate value from the range of several hundreds of angstroms to several hundreds of micrometers. However, for application to a display device, it is preferable that the electrode spacing L be more than a few micrometers. It is in the range of ten micrometers. As for the thickness d of the device electrode, an appropriate numerical value is usually selected from a 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 examined microscopically, usually, a structure in which the individual fine particles are spaced 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 size of the fine particles used in the fine particle film is in the range of several Angstroms to several thousand Angstroms, and particularly preferably in the range of 10 Angstroms to 200 Angstroms.
Further, the thickness of the fine particle film is appropriately set in consideration of various conditions described below. That is, conditions necessary for good electrical connection to the element electrode 1102 or 1103, conditions necessary for performing energization forming described later, and
Conditions necessary for setting the electric resistance of the fine particle film itself to an appropriate value described later, and the like. Specifically, it is set in the range of several Angstroms to several thousand Angstroms, but the range is preferably between 10 Angstroms and 500 Angstroms.

Materials that can be used to form the fine particle film include, for example, Pd, Pt, Ru, Ag,
Au, Ti, In, Cu, Cr, Fe, Zn, Sn, T
a, W, Pb and other metals, PdO, Sn
Oxides such as O2, In2O3, PbO, Sb2O3, etc .; HfB2, ZrB2, LaB6, CeB6, YB
4, borides such as GdB4, TiC, Zr
Carbides such as C, HfC, TaC, SiC, WC, etc .; nitrides such as TiN, ZrN, HfN, etc .; semiconductors such as Si, Ge, etc .; and carbon. Are appropriately selected from these.

As described above, the conductive thin film 1104 is formed of a fine particle film.
It was set so as to be included in the range of 10 3 to 10 7 [Ohm / □].

The conductive thin film 1104 and the device electrode 11
Since it is desirable that the wires 02 and 1103 be electrically connected well, they have a structure in which a part of each overlaps with the other. In the example of FIG. 9, the overlapping manner is such that the substrate, the device electrode, and the conductive thin film are stacked in this order from the bottom, but in some cases, the substrate, the conductive thin film, and the device electrode are stacked in this order from the bottom. I can't wait.

The electron emitting portion 1105 is a crack-like portion formed in a part of the conductive thin film 1104, and has a higher electrical property 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 size of several Angstroms to several hundred Angstroms may be arranged in the crack. Since it is difficult to accurately and accurately show the actual position and shape of the electron-emitting portion, they are schematically shown 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 made of any one of single-crystal graphite, polycrystalline graphite, and amorphous carbon, or a mixture thereof, and has a thickness of 500 [Å] or less, but 300 [Å] or less. Is more preferred. The actual thin film 1113
Since it is difficult to precisely illustrate the position and the shape of, they are schematically shown in FIG. In the plan view (A), an element in which a part of the thin film 1113 is removed is illustrated.

The basic structure of the preferred element has been described above. In the embodiment, the following element is used.
That is, blue glass was used for the substrate 1101, and Ni thin films were used for the device electrodes 1102 and 1103. The thickness d of the device electrode is 1000 [angstrom], and the electrode interval L
Is 2 [micrometers].

Pd or P as the main material of the fine particle film
Using dO, the thickness of the fine particle film was set to about 100 [angstrom], and the width W was set to 100 [micrometer].

Next, a description will be given of a method of manufacturing a suitable planar surface conduction electron-emitting device. FIGS. 10A to 10D
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 in FIG.

(1) First, as shown in FIG.
Element electrodes 1102 and 1103 are formed over a substrate 1101. In forming these electrodes, the substrate 1101 is sufficiently washed beforehand with a detergent, pure water, and an organic solvent, and then the material of the device electrode is deposited (for example, a deposition method such as an evaporation method or a sputtering method). Vacuum film forming technology may be used). Thereafter, the deposited electrode material is patterned by using a photolithography / etching technique, and a pair of device electrodes (1102 and 1102) shown in FIG.
Form 3).

(2) Next, a conductive thin film 1104 is formed as shown in FIG. This conductive thin film 1104
In forming (1), 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 metal compound containing, as a main element, a material of fine particles used for a conductive thin film (specifically, in this embodiment, Pd was used as a main element. In the embodiment, a dipping method is used as a coating method.
Other than that, for example, a spinner method or a spray method may be used).

As a method of forming a conductive thin film made of a fine particle film, other than the method of applying an organic metal solution used in the present embodiment, for example, a vacuum evaporation method, a sputtering method, or a chemical vapor deposition method In some cases, a deposition method or the like is used.

(3) Next, as shown in FIG. 7C, the forming power supply 1110 supplies the device electrodes 1102 and 1111 with each other.
The electron emitting portion 1105 is formed by applying an appropriate voltage during the period 03 and performing the energization forming process.

The energization forming treatment is to energize the conductive thin film 1104 made of a fine particle film, to appropriately destroy, deform, or alter a part of the conductive thin film 1104 to obtain a structure suitable for emitting electrons. This is the process of changing.
A portion of the conductive thin film made of the fine particle film that has been changed to a structure suitable for emitting electrons (that is, the electron emitting portion 110
In 5), an appropriate crack is formed in the thin film.
Note that the electrical resistance measured between the device electrodes 1102 and 1103 is significantly increased after the formation of the electron emission portions 1105 as compared to before the formation.

FIG. 11 shows an example of an appropriate voltage waveform applied from the forming power supply 1110 in order to explain the energization method in more detail. When forming a conductive thin film made of a fine particle film, a pulse-like voltage is preferable. In the case of the present embodiment, a triangular wave pulse having a pulse width T1 is continuously generated at a pulse interval T2 as shown in FIG. Was applied. At that time, the peak value Vpf of the triangular wave pulse is
The pressure was increased sequentially. 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] and the pulse interval T2 is 10 [milliseconds].
[Milliseconds], and the peak value Vpf is set to 0.1 for each pulse.
The voltage was increased by [V]. Then, each time five triangular waves were applied, the monitor pulse Pm was inserted at a rate of once.
In order not to adversely affect the forming process,
The monitor pulse voltage Vpm was set to 0.1 [V].
Then, when the electric resistance between the element electrodes 1102 and 1103 becomes 1 × 10 6 [ohm], that is, when the current measured by the ammeter 1111 when the monitor pulse is applied becomes 1
At the stage where the power became × 10 −7 [A] or less, the 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, and for example, the design of the surface conduction electron-emitting device such as the material and film thickness of the fine particle film or the element electrode interval L is changed. In such a case, it is desirable to appropriately change the energization conditions accordingly.

(4) Next, as shown in FIG.
The device electrodes 1102 and 1103 are supplied from the activation power source 1112.
During the energization activation process, apply an appropriate voltage during
Improve electron emission characteristics. This energization activation process
This is a process of energizing the electron-emitting portion 1105 formed by the energization forming process 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 a 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, 10 minus the fourth power to 1
In a vacuum atmosphere in the range of 0 to the fifth power [torr],
By periodically applying a voltage pulse, carbon or a carbon compound originating from an organic compound existing in a vacuum atmosphere is deposited. The deposit 1113 is any one of single-crystal graphite, polycrystalline graphite, and amorphous carbon, or a mixture thereof, and has a thickness of 500 Å or less, more preferably 300 Å or less.

FIG. 12A shows an example of an appropriate voltage waveform applied from the activation power supply 1112 in order to describe the energization method in more detail. In the present embodiment, the energization activation process is performed by applying a rectangular wave of a constant voltage periodically, but specifically, the rectangular wave voltage Vac is 14
[V], pulse width T3 is 1 [millisecond], pulse interval T
4 is 10 [milliseconds]. The above-mentioned energization conditions are as follows:
This is a preferable condition for the surface conduction electron-emitting device of the present embodiment, and when the design of the surface conduction electron-emitting device is changed, it is desirable to appropriately change the condition accordingly.

An anode electrode 1114 shown in FIG. 10D is for capturing an emission current Ie emitted from the surface conduction electron-emitting device. The anode electrode 1114 is connected to a DC high-voltage power supply 1115 and an ammeter 1116. (Note that the substrate 1101
When the activation process is performed after the display panel is incorporated into the display panel, the phosphor screen of the display panel is connected to the anode electrode 1114.
Used as). While the voltage is applied from the activation power supply 1112, the emission current Ie is measured by the ammeter 1116 to monitor the progress of the energization activation processing, and the activation power supply 111
2 is controlled. An example of the emission current Ie measured by the ammeter 1116 is shown in FIG. Activation power supply 11
When the pulse voltage starts to be applied from 12, the emission current Ie increases with time, but eventually saturates and hardly increases. As described above, when the emission current Ie is substantially saturated, the application of the voltage from the activation power supply 1112 is stopped, and the energization activation process ends.

The above-described energization conditions are preferable conditions for the surface conduction electron-emitting device of the present embodiment. If the design of the surface conduction electron-emitting device is changed, the conditions should be changed accordingly. Is desirable.

As described above, a planar surface conduction electron-emitting device shown in FIG. 10E was manufactured.

(Vertical Type Surface Conduction Emission Element) Next, another typical structure of a surface conduction type emission element in which an electron emission portion or its periphery is formed of a fine particle film, that is, a vertical type surface conduction emission device. The configuration of the element will be described.

FIG. 13 is a schematic sectional view for explaining a vertical basic structure of the present embodiment.
01 is a substrate, 1202 and 1203 are device electrodes, 1206
Denotes a step forming member, 1204 denotes a conductive thin film using a fine particle film, 1205 denotes an electron emitting portion formed by an energization forming process, and 1213 denotes a thin film formed by an energization activation process.

The difference between the vertical type and the flat type described above is that one of the element electrodes (1202) is provided on the step forming member 1206, and the conductive thin film 1204 is provided on the side surface of the step forming member 1206. It is in the point of coating. Therefore, the element electrode interval L in the planar type shown in FIG.
Is the step height L of the step forming member 1206 in the vertical type.
s. In addition, the substrate 1201, the element electrode 1
202 and 1203, conductive thin film 1 using fine particle film
204, the materials listed in the description of the planar type can be used in the same manner. For the step forming member 1206, an electrically insulating material such as SiO2 is used.

Next, a method for manufacturing a vertical surface conduction electron-emitting device will be described. FIGS. 14A to 14F are cross-sectional views for explaining a manufacturing process.
Is the same as

(1) First, as shown in FIG.
An element electrode 1203 is formed over a substrate 1201.

(2) Next, as shown in FIG. 7B, an insulating layer for forming a step forming member is laminated. The insulating layer may be formed by laminating SiO2 by sputtering, for example, but other film forming methods such as vacuum deposition or printing may be used.

3) Next, as shown in FIG. 9C, an element electrode 1202 is formed on the insulating layer.

4) Next, as shown in FIG. 4D, a part of the insulating layer is removed by using, for example, an etching method to expose the element electrode 1203.

5) Next, as shown in FIG. 11E, a conductive thin film 1204 using a fine particle film is formed. For the formation, as in the case of the flat type, a film forming technique such as a coating method may be used.

6) Next, similarly to the case of the flat type, the energization forming process is performed to form an electron emission portion (the same process as the flat type energization forming process described with reference to FIG. 10C). Just do it.)

(7) Next, as in the case of the flat type,
An energization activation process is performed to deposit carbon or a carbon compound in the vicinity of the electron emission portion (the same process as the planar energization activation process described with reference to FIG. 10D may be performed).

As described above, the vertical type surface conduction electron-emitting device shown in FIG.

(Characteristics of Surface Conduction Emission Device Used in Display Device) The element configuration and manufacturing method of the planar and vertical surface conduction electron-emitting devices have been described above. Next, the characteristics of the device used in the display device will be described. Is described.

FIG. 15 shows (emission current Ie) versus (element applied voltage Vf) characteristics of the element used in the display device of the present embodiment.
And typical examples of (device current If) versus (device applied voltage Vf) characteristics. Note that the emission current Ie is significantly smaller than the device current If, and it is difficult to show the same current on the same scale. In addition, these characteristics are changed by changing design parameters such as the size and shape of the device. For,
The two graphs are shown in arbitrary units.

The element used in the display device has the following three characteristics regarding the emission current Ie.

First, the emission current Ie sharply increases when a voltage higher than a certain voltage (this is called a threshold voltage Vth) is applied to the element. On the other hand, when the voltage is lower than the threshold voltage Vth, the emission current Ie increases. Ie is hardly detected. That is, it is a non-linear element having a clear threshold voltage Vth with respect to the emission current Ie.

Secondly, since the emission current Ie changes depending on the voltage Vf applied to the element, the emission current Ie depends on the voltage Vf.
Size can be controlled.

Third, since the response speed of the current Ie emitted from the device is fast with respect to the voltage Vf applied to the device, the amount of charge of the electrons emitted from the device depends on the length of time during which the voltage Vf is applied. Can control.

Because of the characteristics described above, the surface conduction electron-emitting device could be suitably used for 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 Vth according to a desired light emission luminance.
The above voltage is appropriately applied, 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 luminance can be controlled by using the second characteristic or the third characteristic, a gradation display can be performed.

(Structure of a Multi-Electron Source in Which Many Devices are Wired in a Simple Matrix) The structure of a multi-electron source in which the above-mentioned surface conduction electron-emitting devices are arranged on a substrate and wired in a simple matrix will be described.

FIG. 16 is a plan view of the multi-electron source used for the display panel 1000 shown in FIG. Substrate 1
On 001, surface conduction type emission elements similar to those shown in FIG. 9 are arranged, and these elements are wired in a simple matrix by row-direction wiring electrodes 1003 and column-direction wiring electrodes 1004. An insulating layer (not shown) is formed between the row-directional wiring electrodes 1003 and the column-directional wiring electrodes 1004 where they intersect, so that electrical insulation is maintained.

FIG. 17 shows a section taken along the line AA ′ of FIG.

The multi-electron source having such a structure is as follows.
After previously forming a row direction wiring electrode 1003, a column direction wiring electrode 1004, an interelectrode insulating layer (not shown), and a device electrode and a conductive thin film of a surface conduction electron-emitting device on a substrate,
Row direction wiring electrode 1003 and column direction wiring electrode 1004
The device was manufactured by supplying power to each element through the device and performing an energization forming process and an energization activation process.

FIG. 18 shows a configuration in which image information provided from various image information sources such as television broadcasting can be displayed on a display panel using the above-described surface conduction electron-emitting device as an electron source. It is a figure for showing an example of a multifunctional display device. In the figure, 1000 is the display panel described above, 2101 is a display panel driving circuit, 2102 is a display controller, 2103 is a multiplexer, 2104 is a decoder,
2105 is an input / output interface circuit, 2106 is C
PU 2107 is an image generation circuit, 2108 and 210
9 and 2110 are image memory interface circuits,
2111 is an image input interface circuit, 2112 and 2113 are TV signal receiving circuits, and 2114 is an input unit.

(When the present display device receives a signal containing both video information and audio information, such as a television signal, of course, it reproduces the audio simultaneously with the display of the video. Descriptions of circuits, speakers, and the like relating to reception, separation, reproduction, processing, storage, and the like of audio information that are not directly related to the features of the present invention will be omitted.) Hereinafter, the function of each unit will be described along the flow of image signals. go.

First, the TV signal receiving circuit 2113 is a circuit for receiving a TV image signal transmitted using a wireless transmission system such as radio waves or spatial optical communication. The format of the received TV signal is not particularly limited, and may be, for example, various systems such as the NTSC system, the PAL system, and the SECAM system. Further, a TV signal (for example, a so-called high-definition TV including the MUSE system) composed of a larger number of scanning lines than the above is suitable for taking advantage of the display panel suitable for a large area and a large number of pixels. Signal source. 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 21
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 output to a decoder 2104.

The image memory interface circuit 2
110 is a video tape recorder (hereinafter abbreviated as VTR)
Is a circuit for capturing the image signal stored in the decoder 2104. The captured image signal is output to the decoder 2104.

The image memory interface circuit 2
Reference numeral 109 denotes a circuit for capturing an image signal stored in the video disk, and the captured image signal is output to the decoder 2104.

The image memory interface circuit 2
Reference numeral 108 denotes a circuit for taking in an image signal from a device that stores still image data, such as a so-called still image disk.
04 is output.

The input / output interface circuit 210
Reference numeral 5 denotes a circuit for connecting the present display device to an external computer, a computer network, or an output device such as a printer. In addition to inputting and outputting image data, character data, and graphic information, control signals and numerical data can be input and output between the CPU 2106 included in the display device and the outside in some cases. .

The image generation circuit 2107 is provided with image data, character / graphic information input from outside via the input / output interface circuit 2105, or a CPU.
A circuit for generating display image data based on the image data and character / graphic information output from 2106.
Within this circuit, for example, a rewritable memory for storing image data and character / graphic information, a read-only memory for storing image patterns corresponding to character codes, and a processor for performing image processing Circuits necessary for generating an image, such as those described above, are incorporated. The display image data generated by this circuit is
The data is output to an external computer network or a printer via the input / output interface circuit 2105 in some cases.

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, and an image signal to be displayed on the display panel is appropriately selected or combined. In this case, a control signal is generated for the display panel controller 2102 in accordance with an image signal to be displayed, and a display frequency, a scanning method (for example, interlaced or non-interlaced), and the number of scanning lines per screen are displayed. The operation of the device is appropriately controlled.

Further, image data and character / graphic information are directly output to the image generating circuit 2107, or an external computer or memory is accessed via the input / output interface circuit 2105 to access the image data or character / graphic information. Enter graphic information.

The CPU 2106 may, of course, be involved in operations 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, the computer may be connected to an external computer network via the input / output interface circuit 2105 as described above, and operations such as numerical calculations may be performed in cooperation with external devices.

The input unit 2114 is connected to the CPU 21.
06 is for the user to input commands, programs, data, and the like. For example, in addition to a keyboard and a mouse, various input devices such as a joystick, a barcode reader, and a voice recognition device can be used.

Also, the decoder 2104 has the
And 2113 are circuits for inversely converting various image signals inputted from 2113 into three primary color signals or luminance signals and I and Q signals. 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 television signals that require an image memory when performing inverse conversion, such as the MUSE method. Further, the provision of the image memory facilitates the display of a still image, or enables image processing and editing including image thinning, interpolation, enlargement, reduction, and synthesis in cooperation with the image generation circuit 2107 and the CPU 2106. This is because there is an advantage that it can be easily performed.

The multiplexer 2103 is connected to the C
A display image is appropriately selected based on a control signal input from the PU 2106. That is, the multiplexer 2103 selects a desired image signal from the inversely converted image signals input from the decoder 2104 and outputs the selected image signal 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 2
Reference numeral 102 denotes a circuit for controlling the operation of the drive circuit 2101 based on a 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. In addition, a signal for controlling, for example, a screen display frequency and a scanning method (for example, interlaced or non-interlaced), which is related to the display panel driving method, is output to the driving circuit 2101.

In some cases, a control signal related to image quality adjustment such as brightness, contrast, color tone, and sharpness of a display image may be output to the drive circuit 2101.

The driving circuit 2101 is a circuit for generating a driving signal to be applied to the display panel 1000. The driving circuit 2101 is a circuit for generating an image signal input from the multiplexer 2103 and the display panel controller 21.
02 operates based on a control signal input from the control unit 02.

The function of each section has been described above. With the configuration illustrated in FIG. 18, in the present display device, image information input from various image information sources is displayed on the display panel 1.
000 can be displayed. That is, various image signals including television broadcasting are transmitted to the decoder 21.
After the inverse conversion at 04, the multiplexer 2103
And is input to the driving circuit 2101 as appropriate. 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 drive circuit 2101 controls the display panel 1 based on the image signal and the control signal.
000 is applied to the drive signal. Thus, an image is displayed on display panel 1000. These series of operations are totally controlled by the CPU 2106.

In the present display device, an image memory built in the decoder 2104, an image generation circuit 21
07 and the CPU 2106 involve not only displaying a selected one of a plurality of pieces of image information but also enlarging, reducing,
It is also possible to perform image processing such as rotation, movement, edge enhancement, thinning, interpolation, color conversion, image aspect ratio conversion, and image editing such as synthesis, erasure, connection, replacement, and fitting. is there. Although not particularly described in the description of the present embodiment, a dedicated circuit for processing and editing audio information may be provided as in the above-described image processing and image editing.

Accordingly, the present display device is a television broadcast display device, a video conference terminal device, an image editing device that handles still and moving images, a computer terminal device, an office terminal device such as a word processor,
It can be equipped with the functions of a game machine etc. by one unit, and has a very wide application range for industrial or consumer use.

FIG. 18 shows only an example of the configuration of a display device using a display panel using a surface conduction electron-emitting device as an electron source, and it goes without saying that the present invention is not limited to this. No. For example, among the components in FIG. 18, circuits relating to functions that are unnecessary for the intended 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 as a video phone, it is preferable to add a transmission / reception circuit including a television camera, an audio microphone, an illuminator, and a modem to the components.

In the present display device, in particular, since the display panel using the surface conduction electron-emitting device as the electron source can be easily made thin, the depth of the entire display device can be reduced. In addition, since the display panel using the surface conduction electron-emitting device as the electron source is easy to enlarge the screen, has high brightness, and has excellent viewing angle characteristics, this display device is capable of displaying images full of immersion and full of powerful images with good visibility. It is possible to display.

As described above, according to the present embodiment, in a display panel using (m × n) matrix-conducting surface-conduction emission type driving elements driven by pulse width modulation, a cross between adjacent wirings is used. It is possible to suppress a decrease in the effective applied voltage on the wiring that is selectively driven due to the talk, so that an image having good gradation characteristics can be displayed.

[0140]

As described above, according to the present invention, it is possible to suppress the fluctuation of the signal level due to the stray capacitance between the adjacent wirings, and to reproduce the predetermined luminance faithfully and display the image. is there.

Further, according to the present invention, the fluctuation of the signal level on the signal line due to the fall of the signal of the adjacent signal line is minimized, so that the fluctuation of the luminance of the displayed image can be made inconspicuous. There is.

[0142]

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a circuit configuration of an image display device according to a first embodiment of the present invention.

FIG. 2 is a diagram for explaining a problem of the present invention.

FIG. 3 is a diagram for explaining an effect of the circuit of FIG. 1;

FIG. 4 is a diagram illustrating operation timings of the image display devices according to the first and second embodiments of the present invention.

FIG. 5 is a block diagram illustrating a circuit configuration of an image display device according to a second embodiment of the present invention.

FIG. 6 is a diagram for explaining an effect of the circuit of FIG. 5;

FIG. 7 is a partially cutaway perspective view of a display panel of the image display device according to the embodiment of the present invention.

FIG. 8 is a plan view illustrating a phosphor array of a face plate of the display panel of the present embodiment.

FIGS. 9A and 9B are a plan view and a cross-sectional view, respectively, of the planar surface conduction electron-emitting device used in the present embodiment.

FIG. 10 is a cross-sectional view showing a manufacturing process of the planar surface conduction electron-emitting device.

FIG. 11 is a diagram showing an applied voltage waveform during energization forming processing.

FIG. 12 shows an applied voltage waveform (a) during energization activation processing,
It is a figure showing change (b) of discharge current Ie.

FIG. 13 is a sectional view of a vertical surface conduction electron-emitting device used in the present embodiment.

FIG. 14 is a cross-sectional view illustrating a manufacturing process of a vertical surface conduction electron-emitting device.

FIG. 15 is a graph showing typical characteristics of the surface conduction electron-emitting device of the present embodiment.

FIG. 16 is a plan view of a substrate of the multi-electron source used in the present embodiment.

FIG. 17 is a sectional view taken along the line A-A ′ in FIG. 8;

FIG. 18 is a block diagram of a multi-function image display device using the image display device according to the embodiment of the present invention.

FIG. 19 is a diagram showing an example of a conventionally known surface conduction electron-emitting device.

FIG. 20 is a diagram showing an example of a conventionally known FE-type electron-emitting device.

FIG. 21 is a view showing an example of a conventionally known MIM type electron-emitting device.

FIG. 22 is a diagram illustrating a wiring method of an electron-emitting device in which a problem has occurred.

[Explanation of symbols]

 2 Analog signal processing unit 3 A / D unit 4 Synchronous signal separation unit 5 Timing generation unit 6 Horizontal shift register 7 1 line memory 8 Vertical shift register 9 Row wiring drive unit 10 Column wiring drive unit 11 Display panel unit 100 Transistor 101 Pulse width Modulation circuit (PWM GEN) 103, 104, 110 Switch circuit 102 Diode

Claims (20)

[Claims] A row wiring having a plurality of electron-emitting devices and commonly connected to each of the plurality of electron-emitting devices;
An electron source to which the plurality of electron-emitting devices are connected by a column wiring provided corresponding to each of the m electron-emitting devices; and a signal generating means for generating a signal to be applied to the column wiring according to an image signal. When the signal generated by the signal generation unit is a display signal, a current application unit that supplies a current from a first constant current source to a corresponding column wiring; and a signal generated by the signal generation unit is a non-display signal. And driving means for driving the second constant current source to flow a current in a direction opposite to a current direction flowing from the corresponding column wiring by the current applying means. apparatus. 2. The image display device according to claim 1, wherein said signal generating means generates a signal having a pulse width corresponding to a luminance of said image signal. 3. The image display device according to claim 2, wherein said current applying means connects said first constant current source and a column wiring when a pulse signal generated by said signal generating means is on. A first switch circuit for connecting and supplying a current to the column wiring. 4. The image display device according to claim 2, wherein said driving means connects said second constant current source to a column wiring when a pulse signal generated by said signal generating means is off. And a second switch circuit for flowing a current to a lower potential side than the column wiring. 5. The image display device according to claim 1, wherein the plurality of electron-emitting devices are m × m.
It is characterized by being arranged in a matrix of n pieces. 6. The image display device according to claim 5, wherein said row wirings are sequentially selected and driven in accordance with a display timing of said image signal. 7. A row wiring having a plurality of electron-emitting devices and commonly connected to each of the plurality of electron-emitting devices;
An electron source to which the plurality of electron-emitting devices are connected by column wiring provided corresponding to each of the plurality of electron-emitting devices; and a signal generation unit that generates a signal to be applied to the column wiring according to an image signal. When the signal generated by the signal generation unit is a display signal, a current application unit that supplies a current from a first constant current source to a corresponding column wiring; and a signal generated by the signal generation unit is a non-display signal. When applied, an applied voltage lowering means for lowering the corresponding column wiring to a predetermined voltage, and a direction opposite to a direction in which a current is supplied by the current applying means from the column wiring lowered to the predetermined voltage by the applied voltage lowering means. An image display device, comprising: driving means for driving current to flow. 8. The image display device according to claim 7, wherein said signal generation means generates a signal having a pulse width corresponding to the luminance of said image signal. 9. The image display device according to claim 8, wherein said current applying means connects said first constant current source and a column wiring when a pulse signal generated by said signal generating means is on. A first switch circuit for connecting and supplying a current to the column wiring. 10. The image display device according to claim 8, wherein said applied voltage lowering unit connects said predetermined voltage to a column wiring when a pulse signal generated by said signal generating unit is turned off. Thereafter, the driving means has a switch circuit for grounding the column wiring via a resistor. 11. The image display device according to claim 7, wherein the plurality of electron-emitting devices are arranged in a matrix of m × n. 12. The image display device according to claim 11, further comprising sequentially selecting and driving said row wiring in accordance with a display timing of said image signal. 13. The image display device according to claim 1, wherein the electron-emitting device is an FE-type electron-emitting device. 14. The image display device according to claim 1, wherein the electron-emitting device is an image display device.
It is an M-type electron-emitting device. 15. The image display device according to claim 1, wherein said electron-emitting device is a surface conduction electron-emitting device. 16. A plurality of electron-emitting devices, wherein a plurality of electron-emitting devices are connected to each other by a row wiring commonly connected to each of the plurality of electron-emitting devices and a column wiring provided corresponding to each of the plurality of electron-emitting devices. An image display method for displaying an image by driving an electron source to which the electron-emitting device is connected, wherein a signal generating step of generating a signal to be applied to the column wiring according to an image signal; A current applying step of flowing a current from the first constant current source to a corresponding column wiring when the generated signal is a display signal; and a second step when the signal generated in the signal generating step is a non-display signal. A driving step of driving the current to flow in a direction opposite to the direction of the current flowing from the corresponding column wiring by the current applying means from the corresponding column wiring by a constant current source. 17. A semiconductor device comprising: a plurality of electron-emitting devices; a row wiring commonly connected to each of the plurality of electron-emitting devices; and a column wiring provided corresponding to each of the plurality of electron-emitting devices. An image display method for displaying an image by driving an electron source to which the electron-emitting device is connected, wherein a signal generating step of generating a signal to be applied to the column wiring according to an image signal; A current applying step of flowing a current from a first constant current source to a corresponding column wiring when the signal generated in step (a) is a display signal, and a response when the signal generated in the signal generating step becomes a non-display signal. An applied voltage lowering step of lowering the column wiring to a predetermined voltage, and a current flowing in a direction opposite to a direction in which a current flows in the current applying step from the column wiring lowered to the predetermined voltage in the applied voltage lowering step. The image display method characterized by having a driving step of driving the. 18. The image display method according to claim 16, wherein in the signal generating step, a signal having a pulse width corresponding to luminance of the image signal is generated. 19. The image display method according to claim 16, wherein said plurality of electron-emitting devices are arranged in a matrix of m × n. 20. The image display method according to claim 19, further comprising a scanning drive step of sequentially selecting and driving said row wiring in accordance with a display timing of said image signal.