JP3392050B2 - Image display device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image display device having a display panel having a plurality of electron-emitting devices.

[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 inventor of the present application is conducting research using a cold cathode as an electron source as a thin, large-screen display device.

Conventionally, two types of electron-emitting devices are known, a hot cathode device and a cold cathode device. Among them, as the cold cathode element, for example, a surface conduction type emission element, a field emission type element (hereinafter referred to as FE type), a metal / insulating layer / metal type emission element (hereinafter referred to as MIM type), etc. are known. There is.

As the surface conduction type emitting device, for example, M.
I. Elinson, Radio E-ng. Electron Phys., 10, 1290,
(1965) and other examples described later are known.

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

As a typical example of the device structure of these surface conduction type electron-emitting devices, FIG. 19 shows a plan view of the device by M. Hartwell et al. In the figure, 3001 is a substrate, and 3004 is a conductive thin film made of metal oxide formed by sputtering. The conductive thin film 3004 is formed in an H-shaped plane shape as illustrated. An electron-emitting portion 3005 is formed by subjecting this conductive thin film 3004 to an energization process called energization forming described later. The interval L in the figure is 0.5 to 1 [mm], and the width W is
It is set to 0.1 [mm]. For convenience of illustration, the electron emitting portion 3005 is shown in a rectangular shape in the center of the conductive thin film 3004, but this is a schematic one, and the actual position and shape of the electron emitting portion is faithfully expressed. It doesn't mean that.

In the above-mentioned surface conduction electron-emitting device including the device by M. 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. Was common. That is, the energization forming is
A constant DC voltage or a DC voltage which is boosted at a very slow rate of, for example, about 1 V / min is applied to both ends of the conductive thin film 3004 to energize the conductive thin film 3.
That is, 004 is locally destroyed, deformed, or altered to form an electron emitting portion 3005 having a high electrical resistance. A crack occurs in a part of the conductive thin film 3004 which is locally destroyed, deformed or altered. When an appropriate voltage is applied to the conductive thin film 3004 after this energization forming, electrons are emitted near 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 it has a simple structure and is easy to manufacture. Therefore, as disclosed in, for example, Japanese Patent 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) are known.

As a typical example of this FE type element structure, FIG. 20 shows a sectional view of the element by the above-mentioned CA Spindt et al. 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 includes 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. Further, as another element structure of the FE type, as shown in FIG.
There is also an example in which the emitter and the gate electrode are arranged substantially parallel to the substrate plane on the substrate instead of the above laminated structure.

As an example of the MIM type, 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 this MIM type element configuration.
This figure is a cross-sectional view, and in the figure, 3020 is a substrate,
Reference numeral 3021 denotes a lower electrode made of metal, and 3022 has a thickness of 100.
A thin insulating layer of about angstrom, 3023 has a thickness of 8
The upper electrode is made of a metal having a thickness 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 cold cathode device described above can obtain electron emission 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 device, and a fine device can be manufactured. Even if a large number of elements are arranged on the substrate with high density, problems such as heat melting of the substrate are unlikely to occur. In addition, unlike the slow response speed 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 fast. 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, JP-A-64-313 by the present applicant
As disclosed in Japanese Patent No. 32, a method for arranging and driving a large number of devices has been studied.

Regarding 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, a charged beam source, and the like 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 Application Laid-Open No. 2-257551, and Japanese Patent Application Laid-Open No. 4-28137, surface conduction. An image display device using a combination of a die-emitting device and a phosphor that emits light when irradiated with electrons 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, it can be said that it is superior in that it does not require a backlight because it is a self-luminous type and that it has a wide viewing angle, even compared with liquid crystal display devices that have become popular in recent years.

Further, a method of driving a large number of FE type elements side by side is disclosed in, for example, USP 4,904,89 by the present applicant.
5 are disclosed. 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 large number of MIM types are arranged and applied to an image display device is disclosed in, for example, Japanese Patent Laid-Open No. 3-5.
It is disclosed in Japanese Patent No. 5738.

The inventors of the present application have tried 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 an image display device to which the multi-electron source is applied. For example, a multi-electron source has been tried by the electric wiring method shown in FIG. That is, two surface conduction electron-emitting devices are used.
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, 4001 schematically shows a surface conduction electron-emitting device, 4002 is a row direction wiring, and 4003 is a column direction 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 wiring method as described above 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, and in the case of a multi electron source for displaying an image, a desired image is displayed. This is to arrange and wire the elements that are sufficient.

In the multi-electron source in which the surface conduction electron-emitting devices are wired in a simple matrix as described above, appropriate electric signals are applied to the row-direction wirings 4002 and the column-direction wirings 4003 in order to output a desired electron beam. For example,
In order to drive the surface conduction electron-emitting device of any one row 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.
A non-selection voltage Vns is applied to 02. In synchronization with this, a drive voltage Ve for outputting an electron beam is applied to the column-direction wiring 4003. According to this method, the wiring resistance 400
4 and 4005, the voltage of (Ve-Vs) is applied to the surface conduction electron-emitting device of the selected row, and (Ve-Vs) is applied to the surface conduction electron-emitting device of the non-selected row.
Vns) is applied. Here, if Ve, Vs, and Vns are set to appropriate voltages, an electron beam of a desired intensity should be output only from the surface conduction electron-emitting device of the selected row, and each of the column-direction wirings should be output. Different drive voltage Ve
Is applied, electron beams of different intensities should be output from the elements of the selected row. Further, since the response speed of the surface conduction electron-emitting device is high, the driving voltage Ve
It should be possible to change the length of time for which the electron beam is output by changing the length of time for which is applied.

Hereinafter, the element applied voltage (Ve-Vs) at the time of selection
Is called Vf.

Further, as another method for obtaining an electron beam from the multi-electron source having the simple matrix wiring as described above, the driving current is supplied to the column-direction wiring instead of connecting the voltage source for applying the driving voltage Ve. To connect the current source for the selection, and the selection voltage Vs is applied to the row-direction wiring of the row to be selected.
There is also a method of applying the non-selection voltage Vns to the row-direction wiring of the non-selected row at the same time. Thereby, due to the strong threshold characteristic of the surface conduction electron-emitting device, the electron beam can be obtained only from the device in the selected row. Here, the current flowing through the electron source will be referred to as the element current If,
The current generated by the emitted electrons is called the emission current Ie.

Therefore, the multi-electron source in which the surface conduction electron-emitting devices are wired in a simple matrix has various applications. For example, by appropriately applying an electric signal according to image information, it can be used as an electron source for an image display device. It can be preferably used.

[0024]

However, the multi-electron source in which the surface conduction electron-emitting devices are wired in a simple matrix as described above has the following problems.

Up to now, there have been many cases where a CRT is used as a display device of an image display device, and therefore, the correction of a non-linear characteristic between a driving voltage and a light emission amount according to a video signal of the CRT (hereinafter referred to as γ It is common to perform (correction) on the video signal sending side and output the corrected video signal to the display device. An example thereof is shown in FIG. FIG. 6 is a diagram showing a gamma correction characteristic for correcting the relationship between the input signal and the output signal. In the figure, the solid line shows the curve of the BTA and SMPTE standards, and the dotted line shows the correction when γ = 0.45. A curve is shown.

When the video signal corrected according to the γ characteristic is input to an image display device using a display device other than a CRT for display, the drive voltage (current) of the display device and the light emission characteristic of the phosphor. The video signal must be corrected again according to the relationship of. For example, in the case of a display device that expresses gradation by inputting a signal in which multi-valued image data is modulated by pulse width modulation, the relationship between the pulse width of the input video signal and the light emission characteristic becomes linear,
In this case, a non-linear process called inverse γ correction is necessary. In order to perform such inverse gamma correction or conversion according to the light emission characteristics of the device used, it is considered that the method of performing non-linear processing on the video signal is performed by an analog signal or a digital signal. However,
The former has a problem in terms of stability due to changes in temperature and changes with time, and the latter has a problem in that power consumption is increased and cost is increased due to an increase in operating speed and an increase in circuit scale. As described above, in order to perform non-linear processing on the video signal, a circuit of a suitable scale is required, and it has been desired that the emission characteristics can be controlled by the driving method of the display device used.

The present invention has been made in view of the above-mentioned conventional example, and provides an image display device capable of easily converting a video signal into a signal having a desired characteristic and performing display based on the video signal. The purpose is to do.

Another object of the present invention is to provide an image display device for displaying an image by changing the voltage value applied to the elements arranged in a matrix and controlling the output signal for the video signal to a desired value. Especially.

Another object of the present invention is to provide an image display device for displaying an image by changing the current value applied to the elements arranged in a matrix and controlling the output signal for the video signal to a desired value. Especially.

[0030]

In order to achieve the above object, the image display device of the present invention has the following configuration.
That is, an image display device having a display panel in which a plurality of elements having an electron emission characteristic that monotonously changes with respect to a driving voltage or a driving current is arranged, and driving each element of the display panel according to an input video signal. Drive signal generating means for generating a signal, and a control signal generating means for generating a control signal for changing the drive signal of each element independently of the video signal, and for each element according to the control signal. Drive signal changing means for changing the drive signal.

In order to achieve the above object, the device of the present invention has the following configuration. That is, in a device that generates a drive signal for displaying an image on a display panel in which a plurality of elements having an electron emission characteristic that monotonously changes with respect to a drive voltage or a drive current are arranged, the display is performed according to an input video signal. A drive signal generator that generates a drive signal for each element of the panel, and a control signal for changing the drive signal of each element that is generated in the drive signal generator regardless of the video signal, Drive signal changing means for changing the drive signal of each element.

[0032]

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[First Embodiment] FIG. 1 is a block diagram showing a configuration of an image display device according to a first embodiment of the present invention, and FIG. 2 is a timing waveform chart showing an operation of the circuit of FIG.

In FIG. 1, 13 is a display panel in which m × n surface conduction electron-emitting devices are arranged in a matrix.
In addition, the surface conduction electron-emitting device has the device voltage-emission current characteristic shown in FIG. 1 is a video signal input terminal for inputting a video signal, 2 is an analog signal processing unit,
The A / D converter 3 performs black level clamping, amplitude level adjustment, band limitation, etc. of the analog video signal for digitizing the video signal with the required number of gradations. Reference numeral 4 denotes a sync separation unit, which separates the sync signal from the input video signal and outputs it to the timing generation unit 5. The timing generator 5 receives the sync signal from the sync separator 4 and supplies necessary timing signals to the A / D unit 3, the horizontal and vertical shift registers 8 and 10, the arbitrary waveform generator 6, and the like.

Reference numeral 7 denotes a waveform control input section, for example, an adjusted section for the user of this image display apparatus to control the relationship between the luminance signal included in the video signal and the light emission amount to a desired characteristic, and the arbitrary waveform generating section. 6, for example, the user's request information is transmitted as a DC offset adjustment value and a gain adjustment value. The arbitrary waveform generator 6 has voltage values of V1 to V2 for each horizontal scanning cycle, for example.
It generates a sawtooth voltage waveform that changes linearly up to.
The voltage values V1 and V2 are controlled by the DC offset adjustment and the gain adjustment output from the waveform control input unit 7.

The row wiring driving section 9 applies a buffer amplifier 15 having a sufficient driving capability to drive each row wiring of the display panel 13 and a sawtooth voltage waveform from the arbitrary waveform generating section 6 to each row wiring. Switch circuit 16 for selecting whether or not the row wiring is grounded. These switch circuits 16 are provided with a sawtooth pattern of the arbitrary waveform generator 6 on the selected row wiring according to a signal output from the vertical shift register 8. The voltage signal is applied and the other row wirings are grounded.

The video signal processed by the analog processing section 2 is converted into n serial digital signals per horizontal scanning period by the A / D section 3 and sent to the horizontal shift register 10 to be held therein. In this way, the shift register 10
After the video data for one line is stored and converted into a parallel signal, the one-line data is sent to the one-line memory 11 and held therein. The column wiring drive unit 12 applies a DC bias voltage Ve to each column wiring or switches to a ground level, and a pulse proportional to the size of the video data held in the 1-line memory 11. The PWM generator 14 is provided to generate a signal for switching the switch circuit 17 depending on the width. As a result, a voltage pulse having a peak value Ve is applied to the column wiring with a pulse width corresponding to the value of the video data.

FIG. 2 shows the operation timing of each part of FIG. 1, and in FIG. 2, 201 shows an example of the waveform of the input analog video signal. 202 is the A / D unit 3
4 shows an example of digital data obtained by converting the input video signal 201 into a digital signal. Reference numeral 203 shows an example of the waveform of the pulse-width-modulated signal output from the column wiring drive unit 12 to the display panel 13. This pulse signal has a pulse width corresponding to the value of the video data input and converted into digital data. Reference numeral 204 shows an example of the output signal waveform of the vertical shift register 8, which sequentially selects each row wiring in the cycle of the horizontal scanning signal. 205 is an arbitrary waveform generator 6
Shows an example of the waveform of the output signal of the voltage value V1 having a negative polarity
~ V2 is generated (| V1 | <| V2 |). 206
Shows an example of a waveform of a signal output from the row wiring drive section 9 to the display panel 13, and shows a waveform of a voltage signal output from the arbitrary waveform generation section 6 while the output signal of the vertical shift register 8 is at a high level. ing.

Here, temporarily, in the device voltage-emission current characteristic of the surface conduction electron-emitting device shown in FIG.
Is 7.5V and the maximum element applied voltage is "15V", the arbitrary waveform generator 6 is controlled so that the voltage applied to the selected element is 5 to 15V, 7 to 15V, 7 ．
FIG. 3 shows data characteristics between the emission luminance and the pulse width at 5 to 15 V, 8 to 15 V, and 10 to 15 V.

As can be seen from FIG. 3, the element voltages 7 to 1
The relationship between the pulse width and the brightness at 5 V (plotted with “×” in the figure) is closest to the γ characteristic (γ = 2.2) of the CRT, and the relationship between the brightness signal and the light emission amount is arbitrary. It is possible to control by changing the range of the linearly changing voltage output from the waveform generator 6.

In FIG. 3, the description has been given based on the case where the voltage output from the arbitrary waveform generator 6 changes linearly.
Furthermore, for example, by giving a voltage change that superimposes a parabolic waveform on a sawtooth waveform or a voltage change that is expressed by a plurality of broken lines, it is possible to have a light emission characteristic according to the user's preference in addition to γ correction. it can.

[Second Embodiment] FIG. 4 is a block diagram showing a configuration of an image display device according to a second embodiment of the present invention. Portions common to the configuration of the first embodiment described above are denoted by the same reference numerals, The description is omitted.

In the second embodiment, the waveform control input section 7
Is an adjusted part to which a user of this image display device inputs a control signal for controlling the relationship between the luminance signal included in the video signal and the light emission amount to a desired characteristic. From the waveform control input part 7, In response to the input signal, for example, the user's request information is transmitted to the control arbitrary waveform generator 6a as a DC offset adjustment value and a gain adjustment value. The arbitrary waveform generating section 6a, for example, for every horizontal scanning period, has a positive voltage value V1.
A sawtooth voltage waveform that changes linearly up to V2 is generated. These voltage values V1 and V2 are controlled by the DC offset adjustment and gain adjustment output from the waveform control input unit 7.

The row wiring drive unit 9a includes a switch circuit 16 for selecting whether to apply a negative DC voltage Vs to each row wiring of the display panel 13 or to ground the row wiring. When these switch circuits 16 are selected by the output from the vertical shift register 8, by applying the DC voltage Vs to the corresponding row wiring of the display panel 13, the row wiring of the display panel 13 is driven and the display is performed. Be seen.

The A / D unit 3 converts the video analog signal into n serial digital signals per horizontal period, and the horizontal shift register 10 converts it into a parallel signal.
The video data for one line is held in the one-line memory 11. The column wiring driving unit 9a converts the voltage waveform from the arbitrary waveform generating unit 6a into a current waveform for each column wiring.
A switch circuit 17 for selecting either the output of the current source 18 or the ground level, and a signal for switching the switch circuit 17 with a pulse width proportional to the size of the data held in the 1-line memory 11. The PWM generator 14 for generating As a result, the current pulse amplitude-modulated by the arbitrary waveform generator 6a can be applied to each column wiring of the display panel 13 with a pulse width according to the image signal.

The arbitrary waveform generators 6 and 6a described above are
For example, a microprocessor, a memory that stores a program executed by the microprocessor, a D / A
Timing for storing data to be output to the converter and D / A converter, rewritable memory from the microprocessor, and outputting data to the D / A converter for each span obtained by dividing one horizontal period of the video signal by an appropriate integer Means, a low-pass filter for smoothing the D / A converter output with an appropriate time constant, and the like are provided. The waveform control input unit 7 is a user interface for the microprocessor included in the arbitrary waveform generators 6 and 6a, for example, and can change the data in the memory output to the D / A converter.

FIG. 5 is a timing chart showing the operation timing of each part in the configuration of FIG.

The sawtooth output between the voltage values V1 and V2 output from the arbitrary waveform generating section 6a modulates the current source 18 of the column wiring drive section 12a, and the sawtooth output having the current values I1 to 2 is generated. generate. These current drive signals are gated by the switch circuit 17 of the column wiring drive unit 12a by the PWM output modulated with the video data and applied to each column wiring of the display panel 13.

In FIG. 5, reference numeral 301 shows a waveform example of an input analog video signal, and 302 is digital data of each line obtained by converting the analog video signal into a digital signal by the A / D unit 3. 303 is the column wiring drive unit 12
The pulse signal train output from the pulse width modulator 14 of a is shown, and this pulse width has a pulse width according to the value of digital image data. Reference numeral 304 shows a waveform of a signal output from the arbitrary waveform generating section 6a, and 305 shows a waveform of a signal output from the column wiring driving section 12a. This signal waveform, as is clear from the above 303 and 304,
With the same pulse width as the pulse width modulated PWM output signal,
The voltage value corresponds to the level of the voltage signal output from the arbitrary waveform generator 6a. Reference numeral 306 denotes an output signal of the row wiring driving unit 9a that drives each row wiring of the display panel 13 in synchronization with the above-described column wiring driving timing.

In FIG. 5, an example in which the arbitrary waveform generator 6a generates a sawtooth wave has been described, but a nonlinear waveform may be generated as in the first embodiment.
Then, by controlling the output of the arbitrary waveform generator 6a, it is possible to provide the emission luminance characteristic as shown in FIG.

In the first and second embodiments described above, the arbitrary waveform generators 6 and 6a generate the voltage signal between the voltage values V1 and V2 in each horizontal scanning cycle, but the present invention is not limited to this. It is not limited, and it may be a cycle other than this, for example, the cycle of the vertical synchronizing signal, and the change of the voltage value is not as shown in FIG. 2 or FIG. It may be a waveform having

The arbitrary waveform generators 6 and 6a not only follow the input from the waveform control input unit 7 but also generate a predetermined waveform signal, and when there is a change instruction from the waveform control input unit 7, The instructed waveform signal may be generated.

(Structure and Manufacturing Method of Display Panel) Next, the structure and manufacturing method of the display panel 13 of the image display device to which the present invention is applied will be described with reference to specific examples.

FIG. 7 shows the display panel 1 used in the embodiment.
3 is a perspective view of FIG. 3, with a part of the panel cut away to show the internal structure.

In the figure, 1005 is a rear plate, and 1006.
Is a side wall, 1007 is a face plate, and 1005
˜1007 form an airtight container for maintaining a vacuum inside the display panel 13. When assembling an airtight container, it is necessary to seal the joints of each member in order to maintain sufficient strength and airtightness. Sealing was achieved by firing at 400-500 degrees for 10 minutes or more. A method of evacuating the inside of the airtight container will be described later.

The rear plate 1005 has a substrate 1001.
Are fixed, but n × m cold cathode elements 1002 are formed on the substrate 1001 (n and m are positive integers of 2 or more, and are appropriately selected depending on the target number of display pixels). For example, in the case of a display device intended to display a high definition television, n = 3000 and m = 100.
It is desirable to set a number of 0 or more. In this embodiment, n = 3072 and m = 1024). These n × m cold cathode elements are m row-direction wirings 1003.
And n column-direction wirings 1004 form a simple matrix wiring. A portion constituted by the above 1001 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 multi-electron source substrate 1001 is fixed to the rear plate 1005 of the airtight container. However, when the multi-electron source substrate 1001 has sufficient strength, The multi-electron source substrate 1001 itself may be used as the rear plate of the airtight container.

A fluorescent film 1008 is formed on the lower surface of the face plate 1007. Since the present embodiment is a color display device, the phosphor film 1008 is coated with phosphors of three primary colors of red, green and blue used in the field of CRT. The phosphors of each color are shown in FIG.
As shown in (A) of FIG. 5, the conductors 1010 are painted in stripes, and black conductors 1010 are 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 irradiation position of the electron beam is slightly deviated, and to prevent the reflection of external light to prevent the deterioration of the display contrast. Therefore, this is to prevent the fluorescent film from being charged up by the electron beam. Although graphite was used as a main component for the black conductor 1010, other materials may be used as long as they are suitable for the above purpose.

FIG. 8 shows how to separately paint the three primary color phosphors.
The arrangement is not limited to the stripe arrangement shown in FIG. 8A, and for example, a delta arrangement shown in FIG.
Other arrangements may be used. When a monochrome display panel is created, a monochromatic phosphor material may be used for the phosphor film 1008, and a black conductive material may not be necessarily used.

On the surface of the fluorescent film 1008 on the rear plate side, a metal back 1009 known in the field of CRT is used.
Is provided. The purpose of providing the metal back 1009 is to specularly reflect a part of the light emitted by the fluorescent film 1008 to improve the light utilization rate, to protect the fluorescent film 1008 from the collision of negative ions, and to accelerate the electron beam. In order to act as an electrode for applying a voltage, or in the fluorescent film 100.
This is for causing 8 to act as a conduction path for electrons excited. 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 Al (aluminum) 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 1007 and the fluorescent film 100 are 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 the transparent electrode and the electrode 8.

Dx1 to Dxm, Dy1 to Dyn, and Hv are terminals for electrical connection having an airtight structure provided to electrically connect the display panel 13 and the above-mentioned circuit. Dx1 to Dxm are row-direction wirings 1003 of the multi-electron source
And Dy1 to Dyn are multi-electron source column wiring 1004
, 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 the power of 10 minus 7 [to].
Evacuate to a vacuum degree of about [rr]. 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, B
It is a film formed by heating a getter material containing a as a main component with a heater or high-frequency heating and vapor deposition, and the inside of the airtight container is 1 × 10 −5 due to the adsorption action of the getter film.
The degree of vacuum of 1 to 10 × 7 [torr] is maintained.

The display panel 1 according to the embodiment of the present invention has been described above.
The basic configuration and manufacturing method of No. 3 were explained.

Next, a method of manufacturing the multi-electron source used for the display panel 13 of the embodiment will be described. The multi-electron source used in the image display device of the present embodiment is not limited in material, shape, or manufacturing method of the cold cathode element as long as it is an electron source in which cold cathode elements are wired in a simple matrix. Therefore, for example, a surface conduction electron-emitting device, an FE type, or a MIM type cold cathode device can be used.

However, in the situation where a display device having a large display screen and being inexpensive is required, the surface conduction electron-emitting device is particularly preferable among these cold cathode devices. That is, in the FE type, the relative position and shape of the emitter cone and the gate electrode greatly affect the electron emission characteristics, and thus an extremely high-precision manufacturing technique is required, which achieves a large area and a reduction in manufacturing cost. Will be a disadvantageous factor. Further, in the MIM type, it is necessary to make the insulating layer and the upper electrode thin and uniform, which is also a disadvantageous factor in achieving a large area and a reduction in manufacturing cost. In this respect, the surface conduction electron-emitting device has a relatively simple manufacturing method, so that it is easy to increase the area and reduce the manufacturing cost. Further, 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 source of an image display device having high brightness and a large screen. Therefore, in the display panel of the above-described 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 source in which a large number of devices are wired in a simple matrix will be described.

(Preferable Element Configuration of Surface Conduction Type Emitting Element and Manufacturing Method) A typical configuration of a surface conduction type emitting element in which an electron emitting portion or its peripheral portion is formed of a fine particle film is a planar type or a vertical type. There are different types. (Plane-type surface conduction electron-emitting device) First, the element structure and manufacturing method of the plane-type surface conduction electron-emitting device will be described. FIG. 9 is a plan view (a) and a cross-sectional view (b) for explaining the configuration of the flat surface conduction electron-emitting device.

In the figure, 1101 is a substrate, 1102 and 110
3 is a device electrode, 1104 is a conductive thin film, 1105 is an electron emission portion formed by energization forming processing, 1113.
Is a thin film formed by energization activation treatment. Board 11
As 01, for example, various glass substrates such as quartz glass and soda lime glass, various ceramics substrates such as alumina, or substrates obtained by laminating an insulating layer made of, for example, SiO2 on the above various substrates, etc. 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 made of a conductive material. For example, N
i, Cr, Au, Mo, W, Pt, Ti, Cu, Pd,
A material may be appropriately selected from metals such as Ag, alloys of these metals, metal oxides such as In2O3-SnO2, semiconductors such as polysilicon, and the like. The electrodes can be easily formed by combining a film forming technique such as vacuum deposition and a patterning technique such as photolithography and etching, but it can be formed by using another method (for example, a printing technique). It doesn't matter.

The shapes of these 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, but it is preferable that the electrode interval L is several micrometers or more for application to a display device. It is in the range of 10 micrometers. In addition, as for the thickness d of the device electrode, an appropriate numerical value is usually selected from 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 is a film containing a large number of fine particles as constituent elements (including an island-shaped aggregate).
Refers to. A microscopic examination of the particulate film usually reveals that
A structure in which individual fine particles are arranged apart from each other, a structure in which fine particles are adjacent to each other, or a structure in which fine particles overlap each other are observed.

The particle diameter of the fine particles used for the fine particle film is in the range of several angstroms to several thousand angstroms, and the range of 10 angstroms to 200 angstroms is particularly preferable. Further, the film thickness of the fine particle film is appropriately set in consideration of various conditions as described below. That is, the device electrode 11
02 or 1103, conditions necessary for good electrical connection, conditions required for conducting the energization forming described below satisfactorily, conditions necessary for setting the electric resistance of the fine particle film itself to an appropriate value described below. , And so on.

Specifically, it is set within the range of several angstroms to several thousand angstroms, but the range of 10 angstroms to 500 angstroms is particularly preferable.

Materials that can be used to form the fine particle film include, for example, Pd, Pt, Ru, Ag, and A.
u, Ti, In, Cu, Cr, Fe, Zn, Sn, T
Metals such as a, W, Pb, etc., PdO, S
Oxides such as nO2, In2O3, PbO, Sb2O3, HfB2, ZrB2, LaB6, CeB6,
Borides such as YB4, GdB4, etc., Ti
Carbides such as C, ZrC, HfC, TaC, SiC, WC, etc., nitrides such as TiN, ZrN, HfN, etc., semiconductors such as Si, Ge, etc., carbon, etc. And can be appropriately selected from these.

As described above, the conductive thin film 1104 is formed of a fine particle film, and its sheet resistance value is
It was set to fall within the range of 10 3 to 10 7 [ohm / sq].

The conductive thin film 1104 and the device electrode 11
Since 02 and 1103 are preferably electrically connected well, they have a structure in which some of them overlap each other. In the example of FIG. 9, the layers are stacked in the order of the substrate, the device electrode, and the conductive thin film 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. It doesn't matter.

The electron emitting portion 1105 is a crack-like portion formed in a part of the conductive thin film 1104, and has an electrically higher resistance than the surrounding conductive thin film. The crack is formed by subjecting the conductive thin film 1104 to a later-described energization forming process. Fine particles having a particle diameter of several angstroms to several hundred angstroms may be arranged in the cracks. Since it is difficult to accurately and accurately illustrate the actual position and shape of the electron-emitting portion, the electron-emitting portion is 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 the energization activation process described later after the energization forming process.

The thin film 1113 is made of single crystal graphite, polycrystalline graphite, amorphous carbon, or a mixture thereof, and has a film thickness of 500 [angstrom] or less, but 300 [angstrom] or less. Is more preferable.

Since it is difficult to accurately illustrate the actual position and shape of the thin film 1113, it is schematically shown in FIG. In the plan view (a), the thin film 111
A device in which a part of 3 is removed is shown.

The basic structure of a preferable element has been described above, but the following elements were used in the embodiments.

That is, soda lime 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 was 1000 [angstrom], and the electrode interval L was 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 the width W is 1
00 [micrometer].

Next, a method for manufacturing a suitable plane type surface conduction electron-emitting device will be described.

FIGS. 10A to 10D are sectional views 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.
The device electrodes 1102 and 1103 are formed on the substrate 1101. In forming these element electrodes, the substrate 1101 is thoroughly washed in advance with a detergent, pure water, and an organic solvent, and then the element electrode material is deposited. (As a method for depositing, for example, a vacuum film forming technique such as a vapor deposition method or a sputtering method may be used.) After that, the deposited electrode material is patterned by using photolithography / etching technique to form (a). The pair of device electrodes shown (1102 and 11
03) is formed.

(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 of (a), dried, heated and baked to form a fine particle film, and then patterned into a predetermined shape by photolithography and etching. . here,
The organometallic solution is a solution of an organometallic compound whose main element is the material of the fine particles used for the conductive thin film. (Specifically, Pd is used as the main element in the present embodiment.
Further, although the dipping method is used as the coating method in the embodiment, other methods such as a spinner method and a spray method may be used).

Further, as a method for forming a conductive thin film made of a fine particle film, other than the method of applying the organic metal solution used in the present embodiment, for example, a vacuum vapor deposition method, a sputtering method, or a chemical vapor phase method. A deposition method may be used in some cases.

(3) Next, as shown in FIG. 7C, the forming power source 1110 to the device electrodes 1102 and 11
An appropriate voltage is applied during the period 03 to carry out energization forming processing to form the electron emitting portion 1105. This energization forming process is a conductive thin film 1 made of a fine particle film.
104 is energized, and a part of it is appropriately destroyed, deformed,
Alternatively, it is a treatment for changing the structure to 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 11
After the formation of 05, the electric resistance measured between the device electrodes 1102 and 1103 after the formation is significantly increased.

In order to explain the energization method in more detail, FIG. 11 shows an example of an appropriate voltage waveform applied from the forming power supply 1110. 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 triangular wave pulse having a pulse width T1 is continuously provided at a pulse interval T2 as shown in FIG. Applied. In that case, the peak value Vpf of the triangular pulse is
The pressure was sequentially increased. Also, monitor pulses Pm for monitoring the formation state of the electron emission portion 1105 are inserted between the triangular wave pulses at appropriate intervals, and the current flowing at that time is measured by the ammeter 1.
Measured at 111.

In the embodiment, the pulse width T1 is 1 [millisecond] and the pulse interval T2 is 10 in a vacuum atmosphere of about 10 <-5> [torr].
[Millisecond], and the peak value Vpf is set to 0.1 for each pulse.
The voltage was increased by [V]. The monitor pulse Pm was inserted once every five pulses of the triangular wave were applied.
In order not to adversely affect the forming process,
The voltage Vpm of the monitor pulse was set to 0.1 [V].
Then, when the electric resistance between the device electrodes 1102 and 1103 becomes 1 × 10 6 [ohm], that is, when the monitor pulse is applied, the current measured by the ammeter 1111 is 1
When the power became less than or equal to × 10 minus [7] [A], the energization related to the forming process was terminated.

The above method is a preferable method for the surface conduction electron-emitting device according to the present embodiment. 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 spacing L is changed. In that case, it is desirable to appropriately change the energization conditions accordingly.

(4) Next, as shown in FIG. 10D, the activation power supply 1112 to the device electrodes 1102 and 11
During 03, an appropriate voltage is applied to carry out energization activation treatment to improve electron emission characteristics.

The energization activation process 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 the member 1113.) Note that by performing the energization activation treatment, the emission current at the same applied voltage is typically compared to that before the activation. Specifically, it can be increased 100 times or more.

Specifically, it is 10 −4 or 1
By periodically applying a voltage pulse in a vacuum atmosphere within a range of 0 minus 5 [torr], carbon or a carbon compound originating from an organic compound existing in the vacuum atmosphere is deposited. The deposit 1113 is one of single crystal graphite, polycrystalline graphite, amorphous carbon, or a mixture thereof, and has a film thickness of 500.
[Angstrom] or less, more preferably 300 [Angstrom] or less.

In order to explain the energization method in more detail, FIG. 12A shows an example of an appropriate voltage waveform applied from the activation power supply 1112. In the present embodiment, the energization activation process is performed by periodically applying a rectangular wave having a constant voltage. Specifically, the rectangular wave voltage Vac is 14
[V], pulse width T3 is 1 [millisecond], pulse interval T4
Was set to 10 [milliseconds]. The above-mentioned energization conditions are preferable conditions for the surface conduction electron-emitting device of the present embodiment, and when the design of the surface conduction electron emission device is changed, it is desirable to appropriately change the condition accordingly.

Reference numeral 1114 shown in FIG. 9 (d) is an anode electrode for trapping the emission current Ie emitted from the surface conduction electron-emitting device, to which a DC high voltage power supply 1115 and an ammeter 1116 are connected. The substrate 1101 is
When the activation treatment is performed after the display panel is incorporated into the display panel, the fluorescent surface of the display panel is used as the anode electrode 1114. 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 process, and the activation power supply 1112 is monitored.
Control the behavior of. An example of the emission current Ie measured by the ammeter 1116 is shown in FIG.
When the pulse voltage is started to be applied from 12, the emission current Ie increases with the lapse of time, but eventually saturates and hardly increases. In this way, when the emission current Ie is almost saturated, the voltage application from the activation power supply 1112 is stopped, and the energization activation process ends.

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

As described above, the plane type surface conduction electron-emitting device shown in FIG. 10E was manufactured.

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

FIG. 13 is a schematic sectional view for explaining the basic structure of the vertical type, in which 1201 is a substrate.
202 and 1203 are element electrodes, 1206 is a step forming member, 1204 is a conductive thin film using a fine particle film, 1205
Is an electron emission portion formed by the energization forming process, 1
213 is a thin film formed by the energization activation process.

The vertical type is different from the above-described flat type in that one of the element electrodes (1202) is provided on the step forming member 1206, and the conductive thin film 1204 covers the side surface of the step forming member 1206. The point is that they are covered. Therefore, the device electrode interval L in the flat type shown in FIG. 9 is set as the step height Ls of the step forming member 1206 in the vertical type. For the substrate 1201, the device electrodes 1202 and 1203, and the conductive thin film 1204 using a fine particle film, it is possible to use the materials listed in the description of the planar type similarly. Also, the step forming member 1206
For this, an electrically insulating material such as SiO2 is used.

Next, a method of manufacturing a vertical type surface conduction electron-emitting device will be described. 14A to 14F are cross-sectional views for explaining the manufacturing process, and the notation of each member is the same as that in FIG.

(1) First, as shown in FIG.
A device electrode 1203 is formed on the substrate 1201.

(2) Next, as shown in FIG. 10B, an insulating layer for forming the step forming member is laminated. The insulating layer may be formed by laminating, for example, SiO2 by a sputtering method.
For example, another film forming method such as a vacuum vapor deposition method or a printing method may be used.

(3) Next, as shown in FIG. 10C, the device electrode 1202 is formed on the insulating layer.

(4) Next, as shown in FIG. 9D, a part of the insulating layer is removed by using, for example, an etching method to expose the device electrode 1203.

(5) Next, as shown in FIG. 7E, a conductive thin film 1204 using a fine particle film is formed. For formation, a film forming technique such as a coating method may be used as in the case of the flat type.

(6) Next, as in the case of the flat type,
An energization forming process is performed to form an electron emitting portion.
(The same process as the planar energization forming process described with reference to FIG. 10C may be performed.) (7) Next, as in the case of the planar type, the energization activation process is performed to emit electrons. Carbon or a carbon compound is deposited near the portion. (The same process as the planar energization activation process described with reference to FIG. 10D may be performed.) As described above, the vertical surface conduction electron-emitting device shown in FIG. Manufactured.

(Characteristics of Surface Conduction Type Emitting Element Used in Display Device) The element structure and manufacturing method of the plane type and vertical type surface conduction type emitting element have been described above. I will describe.

FIG. 15 shows typical examples of the (emission current Ie) vs. (device applied voltage Vf) characteristics and the (device current If) vs. (device applied voltage Vf) characteristics of the device used in the display device. The emission current Ie is significantly smaller than the device current If, and it is difficult to illustrate them on the same scale. Moreover, these characteristics are changed by changing design parameters such as the size and shape of the device. Therefore, the two graphs are shown in arbitrary units.

The element used in the display device of this embodiment is
The emission current Ie has the following three characteristics.

First, when a voltage larger than a certain voltage (which is called a threshold voltage Vth) is applied to the element, the emission current Ie rapidly increases. On the other hand, when the voltage is less 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 at the voltage Vf.
You can control the size of.

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 the electrons emitted from the element depends on the length of time the voltage Vf is applied. You can control.

Due to the above-mentioned characteristics, the surface conduction electron-emitting device could be suitably used for the display device. For example, in a display device in which a large number of elements are provided corresponding to the pixels of the display screen, by utilizing the first characteristic, it is possible to sequentially scan and display the display screen. That is, a voltage equal to or higher than the threshold voltage Vth is appropriately applied to the driven element according to the desired light emission luminance, and a voltage lower than the threshold voltage Vth is applied to the non-selected element. By sequentially switching the elements to be driven, it is possible to sequentially scan the display screen for display.

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 Source Having Many Elements Wiring in Simple Matrix) Next, the structure of a multi electron source in which the above surface conduction electron-emitting devices are arranged on a substrate and wiring is carried out in simple matrix will be described.

FIG. 16 shows the display panel 13 of FIG.
FIG. 3 is a plan view of a multi-electron source used in FIG. Surface conduction electron-emitting devices similar to those shown in FIG. 9 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 1003 and column-direction wiring electrode 1004
Insulation layers (not shown) are formed between the electrodes at the intersections of, and electrical insulation is maintained.

A cross section taken along the line AA 'in FIG. 16 is shown in FIG.

The multi-electron source having such a structure is
After the row-direction wiring electrodes 1003, the column-direction wiring electrodes 1004, the inter-electrode insulating layer (not shown), and the element electrodes of the surface conduction electron-emitting device and the conductive thin film are formed on the substrate 1001 in advance, the row-direction wiring electrodes 1003 and Column-direction wiring electrode 10
The device was manufactured by supplying power to each element via 04 and performing an energization forming process and an energization activation process.

FIG. 18 is configured so that image information provided from various image information sources such as television broadcasting can be displayed on a display panel using the surface conduction electron-emitting device described above as an electron source. It is a figure for showing an example of a multi-function 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, 2106 is a CPU, 210
7 is an image generation circuit, 2108, 2109 and 21.
10 is an image memory interface circuit, 2111 is an image input interface circuit, 2112 and 2113.
Is a TV signal receiving circuit, and 2114 is an input unit. In addition,
When the display device receives a signal including both video information and audio information, such as a television signal, it naturally reproduces audio at the same time as displaying video. Descriptions of circuits, speakers, etc. relating to reception, separation, reproduction, processing, storage, etc. of unrelated voice information are omitted.

The functions of the respective parts will be described below in accordance with the flow of the image signal.

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 system of the TV signal to be received is not particularly limited, and various systems such as NTSC system, PAL system and SECAM system may be used. Further, a TV signal (for example, a so-called high-definition TV such as the MUSE method) including a larger number of scanning lines than these is suitable for taking advantage of the display panel suitable for a large area and a large number of pixels. It is a signal source. The TV signal received by the TV signal receiving circuit 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 wire transmission system such as a coaxial cable or an optical fiber. Similar to the TV signal receiving circuit 2113, the system of the TV signal to be received is not particularly limited, and the TV signal received by this circuit is also output to the decoder 2104.

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
It is a circuit for connecting the display device to an external computer, a computer network, or an output device such as a printer. It is of course possible to input and output image data, character data, and graphic information, and in some cases, input and output control signals and numerical data between the CPU 2106 of this display device and the outside. .

Further, the image generating circuit 2107 is provided with image data, character / graphic information, or CPU which is externally input through the input / output interface circuit 2105.
2106 is a circuit for generating display image data based on image data and character / graphic information output from the 2106.
Inside this circuit, for example, a rewritable memory for accumulating image data and character / graphic information, a read-only memory in which image patterns corresponding to character codes are stored, and a processor for performing image processing Etc. and the circuits necessary for image generation are incorporated. The display image data generated by this circuit is the decoder 2
Although it is output to 104, it is also possible to input / output to / from an external computer network or printer via the input / output interface circuit 2105 in some cases.

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 for the display panel controller 2102 according to the image signal to be displayed, and the screen display frequency, the scanning method (for example, interlaced or non-interlaced), the number of scanning lines in one screen, etc. are displayed. The operation of the device is controlled appropriately.

Image data or character / graphic information is directly output to the image generation circuit 2107, or an external computer or memory is accessed via the input / output interface circuit 2105 to obtain image data or character / figure information. Enter graphic information.

It should be noted that the CPU 2106 may of course be involved in work for purposes other than this. For example,
It may be directly related to the function of generating and processing information, such as a personal computer or a word processor.

Alternatively, as described above, the computer may be connected to an external computer network through the input / output interface circuit 2105, and work such as numerical calculation may be performed in cooperation with an external device.

The input unit 2114 is the CPU 21
A user inputs commands, programs, data, etc. at 06. For example, various input devices such as a joystick, a bar code reader, and a voice recognition device can be used in addition to a keyboard and a mouse.

Further, the decoder 2104 has the above-mentioned 2107.
Is a circuit for inversely converting various image signals input from the to 2113 into three primary color signals or luminance signals and I signals and Q signals. Note that it is desirable that the decoder 2104 includes an image memory therein, as indicated by a dotted line in the figure. This is to handle a television signal that requires an image memory for reverse conversion, such as the MUSE method. Further, the provision of the image memory facilitates the display of a still image, or cooperates with the image generation circuit 2107 and the CPU 2106 to perform image processing and editing such as image thinning, interpolation, enlargement, reduction, and composition. This is because there is an advantage that it can be easily performed.

Further, the multiplexer 2103 has the C
The display image is appropriately selected based on the 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 it to the drive circuit 2101. In that case, by switching and selecting image signals within one screen display time, it is possible to divide one screen into a plurality of areas and display different images depending on the areas, as in a so-called multi-screen television. .

Display panel controller 2102
Is a circuit for controlling the operation of the drive circuit 2101 based on a control signal input from the CPU 2106.

First, as a device related to the basic operation of the display panel, for example, a signal for controlling the operation sequence of a power source (not shown) for driving the display panel is output to the drive circuit 2101. Further, as a method related to the driving method of the display panel, 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.

The drive circuit 2101 is a circuit for generating a drive signal to be applied to the display panel 2100, and based on the image signal input from the multiplexer 2103 and the control signal input from the display panel controller 2102. It works.

The functions of the respective parts have been described above. With the configuration illustrated in FIG. 18, the display panel 2 displays image information input from various image information sources in this display device.
It is possible to display 100. That is, various image signals such as television broadcast are transmitted to the decoder 21.
After inverse conversion at 04, multiplexer 2103
Are selected as appropriate 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 drive circuit 2101 controls the display panel 2 based on the image signal and the control signal.
A drive signal is applied to 100. As a result, the image is displayed on the display panel 2100. A series of these operations are controlled by the CPU 2106.

Further, in this display device, the image memory built in the decoder 2104 and the image generation circuit 21.
Due to the involvement of 07 and the CPU 2106, not only the one selected from a plurality of image information is displayed, but also the image information to be displayed is enlarged or reduced, for example.
It is also possible to perform image processing such as rotation, movement, edge enhancement, thinning, interpolation, color conversion, aspect ratio conversion of images, and image editing such as composition, deletion, connection, replacement, and fitting. is there. Although not particularly mentioned in the description of the present embodiment, a dedicated circuit for processing and editing audio information may be provided as in the above-mentioned image processing and image editing.

Therefore, the display device is a display device for television broadcasting, a terminal device for a video conference, an image editing device for handling still images and moving images, a computer terminal device, an office terminal device such as a word processor,
It is possible to combine the functions of a game console, etc., with a very wide range of applications for industrial or consumer use.

Note that FIG. 18 shows only an example of the structure of a display device using a display panel having a surface conduction electron-emitting device as an electron source, and it is needless to say that the present invention is not limited to this. Yes. For example, of the constituent elements in FIG. 18, circuits relating to functions that are unnecessary for the purpose of use may be omitted. On the contrary, the constituent elements may be added depending on the purpose of use. For example, when the display device is applied as a video telephone, it is preferable to add a television camera, a voice microphone, an illuminator, a transmission / reception circuit including a modem, and the like to the components.

In the present display device, in particular, since the display panel using the surface conduction electron-emitting device as an electron source can be easily thinned, the depth of the entire display device can be reduced. In addition, a display panel using surface conduction electron-emitting devices as an electron source can easily enlarge the screen, has high brightness, and has excellent viewing angle characteristics, so this display device provides a realistic and powerful image with good visibility. It is possible to display.

Even if the present invention is applied to a system composed of a plurality of devices (eg, host computer, interface device, reader, printer, etc.), a device composed of one device (eg, copier, facsimile) Device).

Further, an object of the present invention is to supply a storage medium storing a program code of software for realizing the functions of the above-described embodiment to a system or apparatus, and to supply a computer (or CPU) of the system or apparatus.
Or MPU) reads and executes the program code stored in the storage medium.

In this case, the program code itself read from the storage medium realizes the functions of the above-described embodiments, and the storage medium storing the program code constitutes the present invention.

As a storage medium for supplying the program code, for example, a floppy disk, a hard disk, an optical disk, a magneto-optical disk, a CD-ROM, a CD
-R, magnetic tape, non-volatile memory card, ROM, etc. can be used.

Moreover, not only the functions of the above-described embodiments are realized by executing the program code read by the computer, but also the OS (operating system) running on the computer based on the instructions of the program code. ) And the like perform some or all of the actual processing, and the processing realizes the functions of the above-described embodiments.

Further, after the program code read from the storage medium is written in the memory provided in the function expansion board inserted into the computer or the function expansion unit connected to the computer, based on the instruction of the program code, This also includes a case where a CPU or the like included in the function expansion board or the function expansion unit performs some or all of the actual processing and the processing realizes the functions of the above-described embodiments.

As described above, according to this embodiment, a plurality of electron-emitting devices arranged in a matrix,
In an image display device that displays an image using a display panel including a plurality of phosphors that emit light by electrons emitted from these electron-emitting devices, a signal corresponding to an input video signal is applied to a column wiring of the display panel. , The image can be displayed by sequentially selecting and driving the row wirings of the display panel in synchronization with the input video signal. At that time, the control signal is generated independently of the video signal, and the control signal is generated according to the control signal. By changing the voltage level of the selected row wiring or changing the voltage value or current value applied to the column wiring, the amount of electrons emitted from each electron-emitting device is controlled and the amount of light emission is controlled. Can be controlled.

Since the control signal can be arbitrarily set or changed by the user, the display brightness with respect to the input video signal level can be changed according to the characteristics of the display device.

[0151]

As described above, according to the present invention, it is possible to easily convert a video signal into a signal having a desired characteristic and perform display based on the video signal.

According to the present invention, it is possible to display an image by changing the voltage value applied to the elements arranged in a matrix and controlling the output signal for the video signal to a desired value.

Further, according to the present invention, it is possible to display an image by changing the current value applied to the elements arranged in a matrix and controlling the output signal for the video signal to a desired value.

[0154]

[Brief description of drawings]

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

FIG. 2 is a timing chart for explaining each signal in the image display device of FIG.

3A and 3B are diagrams illustrating an example in which a relationship between luminance and pulse width in Embodiment 1 depends on a voltage value of a scan signal.

FIG. 4 is a block diagram showing a configuration of an image display device according to a second embodiment of the present invention.

5 is a timing diagram for explaining each signal in the image display device of FIG.

FIG. 6 is a diagram illustrating a γ correction characteristic.

FIG. 7 is a perspective view in which a part of the display panel of the image display device according to the embodiment of the present invention is cut away.

FIG. 8 is a plan view exemplifying an arrangement of phosphors on a face plate of the display panel of the present embodiment.

FIG. 9 is a plan view (a) and a cross-sectional view (b) of a planar surface conduction electron-emitting device used in this embodiment.

FIG. 10 is a cross-sectional view showing a manufacturing process of the flat surface-conduction type electron-emitting device used in the present embodiment.

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

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

FIG. 13 is a cross-sectional view of a vertical type surface conduction electron-emitting device used in this embodiment.

FIG. 14 is a cross-sectional view showing the manufacturing process of the vertical surface conduction electron-emitting device used in the present embodiment.

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

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

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

FIG. 18 is a block diagram of a multifunctional 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.

FIG. 21 is a diagram showing an example of a conventionally known MIM type.

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

[Explanation of symbols]

4 Sync signal separation unit 5 Timing generator 6,6a Arbitrary waveform generator 7 Waveform control input section 9,9a Row wiring drive unit 10 Horizontal shift register 11 1 line memory 12, 12a Column wiring drive unit 13 Display panel

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) G09G 3/22 G09G 3/20 641 G09G 3/20 650

Claims (12)

(57) [Claims] 1. An image display device having a display panel in which a plurality of elements having an electron emission characteristic that monotonously changes with respect to a drive voltage or a drive current are arranged, each of the display panels according to an input video signal. Drive signal generating means for generating a drive signal for the element, a control signal for changing the drive signal for each element, a control signal generating means for generating independent of the video signal, and the control signal according to the control signal An image display device comprising: a drive signal changing unit that changes a drive signal of each element. 2. The drive signal generating means stores one line storage means for storing at least one line of an input video signal, and a signal having a pulse width corresponding to each video signal value stored in the one line storage means. A pulse width modulating unit that generates the voltage, a voltage applying unit that applies a voltage to the column direction wiring for a time corresponding to the pulse width of the signal output from the pulse width modulating unit, and the row direction wiring of the display panel in order. The image display device according to claim 1, further comprising a horizontal scanning unit that selects and applies a voltage signal according to the control signal. 3. The drive signal generating means stores one line memory means for storing at least one line of the input video signal, and a signal having a pulse width corresponding to each video signal value stored in the one line memory means. A pulse width modulating means for generating, a current applying means for applying a current signal according to the control signal to the column direction wiring for a time according to the pulse width of a signal output from the pulse width modulating means, the display panel 2. The image display device according to claim 1, further comprising: a horizontal scanning unit that sequentially selects the row-direction wirings and applies a predetermined voltage. 4. The control signal is a signal that linearly changes from a first voltage value V1 to a second voltage value V2 in a predetermined time period. The image display device according to. 5. The image display device according to claim 1, wherein the plurality of elements are FE type emission elements. 6. The image display device according to claim 1, wherein the plurality of elements are MIM type emission elements. 7. The image display device according to claim 1, wherein the plurality of elements are surface conduction electron-emitting devices. 8. A device for generating a drive signal for displaying an image on a display panel in which a plurality of elements having an electron emission characteristic that monotonously changes with respect to a drive voltage or a drive current are arranged, and the device generates a drive signal according to an input video signal. A drive signal generator that generates a drive signal for each element of the display panel, and a control signal that is generated in the drive signal generator regardless of the video signal and that changes the drive signal for each element. And a drive signal changing unit that changes the drive signal of each element. 9. The drive signal generation unit stores a 1-line storage unit that stores an input video signal for at least one line, and a signal having a pulse width corresponding to each video signal value stored in the 1-line storage unit. 9. A pulse width modulating means for generating the voltage, and a voltage applying means for applying a voltage to the column-direction wiring for a time corresponding to the pulse width of the signal output from the pulse width modulating means. The device according to. 10. The drive signal generating section stores one line storage means for storing at least one line of an input video signal, and a signal having a pulse width corresponding to each video signal value stored in the one line storage means. Pulse width modulating means for generating, and current applying means for applying a current signal according to the control signal to the column direction wiring for a time according to the pulse width of the signal output from the pulse width modulating means. 9. The device according to claim 8, characterized in that 11. A horizontal scanning means for sequentially selecting the row-direction wirings of the display panel and applying a voltage signal according to the control signal.
The apparatus according to any one of 1. 12. The control signal is a signal that linearly changes from a first voltage value V1 to a second voltage value V2 in a predetermined time, according to any one of claims 8 to 10. The device according to.