JP2002372945A - Image forming apparatus and image forming method - Google Patents

Abstract

(57) [Abstract] [Purpose] In an image forming apparatus using a surface conduction electron-emitting device, it is excellent in gradation expression characteristics, and it is easy to control color misregistration and color balance when colorization is performed on a receiver side. And an image forming apparatus and method that can be realized. [Structure] Matrix circuit 314 and gamma correction circuit 3
At steps 13 and 315, the NTSC signal is converted into an RGB signal. At this time, the conversion is performed so as to correct the non-linearity of the emission luminance characteristics of the phosphor of each color. Pulse width modulation circuit 31
Numeral 6 executes pulse width modulation on a signal in which the nonlinearity of the emission luminance characteristic of the phosphor is linearly corrected. At this time,
A signal to be superimposed on each color signal is determined in order to correct the variation in the light emission luminance characteristics of the phosphors of each color that have been linearly converted. An electron beam is emitted based on the determined signal and is irradiated on the phosphor.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electron source and an image forming apparatus such as a display device to which the present invention is applied, and more particularly, to a color display by arranging a plurality of cold cathode electron sources two-dimensionally on a plane. The present invention relates to an image forming apparatus and an image forming method.

[0002]

2. Description of the Related Art Conventionally, two types of electron emitting devices, a thermionic electron source and a cold cathode electron source, are known.

[0003] Cold cathode electron sources include a field emission type (hereinafter abbreviated as FE), a metal / insulating layer / metal type (hereinafter abbreviated as MIM), and a surface conduction electron-emitting device (hereinafter abbreviated as SCE).

[0004] Examples of the FE type include WPDyke & WWDol.
an, "Filed emission", Advance inElectron Physics,
8,89 (1956) and CASpindt, "PHYSICAL properties of
thin-film field emission cathodes with molybdeniu
m cones ", J. Appl phys., 47, 5248 (1976).

As an example of the MIM type, CAMead, "T
he tunnel-emission amplifier ", J.Appl.Phys., 32,64
6 (1961) and the like are known.

Further, as an example of the SCE type, MIElinso
n, Radio Eng. Electron Pys. 10, (1965).

[0007] The SCE type 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.

As the surface conduction electron-emitting device, a device using the above-mentioned SnO ₂ thin film by Elinson or the like, a device using an Au thin film (G. Dittmer: “Thin Solid Fi
lms ", 9,319 (1972)) In ₂ O ₃ / SnO ₂ thin film
(M.Hartwell and CGFonstad; "IEEE Trans.ED Conf."
, 519 (1975)), using carbon thin film (Hisashi Araki et al .:
Vacuum, Vol. 26, No. 1, p. 22 (1983)).

As a typical device configuration of these surface conduction electron-emitting devices, the device configuration of the aforementioned M. Hartwell is shown in FIG. In the figure, 250
1 is an insulating substrate. Reference numeral 2502 denotes an H-type electron emitting portion forming thin film, which is formed of a metal oxide thin film or the like formed by sputtering. The electron emitting portion 2503 is formed by an energization process called forming described later. Reference numeral 2504 denotes a thin film for forming an electron-emitting portion in which an electron-emitting portion 2503 is formed, which is referred to as a thin film including an electron-emitting portion. In the figure, L1 is set to 0.5 to 1 mm, and W is set to 0.1 mm.

Conventionally, in these surface conduction electron-emitting devices, the electron-emitting portion forming thin film 2 is formed before electron emission.
Generally, the electron-emitting portion 2503 is formed in advance in the 502 by an energization process called forming. Here, forming refers to a thin film 2502 for forming an electron-emitting portion.
Voltage is applied to both ends of the thin film transistor 25, and the thin film 25 for forming the electron emission portion is applied.
02 is locally destroyed, deformed or altered to form an electron emitting portion 2503 in an electrically high-resistance state.

Note that a crack is generated in a part of the thin film 2502 for forming an electron emission portion by the forming process, and electrons are emitted from the vicinity of the crack. The surface conduction type electron-emitting device that has been subjected to the forming process is configured to apply a voltage to the thin film 2502 including the above-described electron-emitting portion and to cause a current to flow through the device to cause the electron-emitting portion 2503 to emit electrons.

Although these conventional surface conduction electron-emitting devices have various problems in practical use,
The inventors have diligently studied various improvements described below, and have solved various problems in practical use.

The above-described surface conduction electron-emitting device has an advantage that a large number of devices can be arranged and formed over a large area because of its simple structure and easy manufacture. Therefore, various applications that make use of this feature are being studied. For example, a charged beam source, a display device, and the like can be given. An example of an array of a large number of surface conduction electron-emitting devices is an electron source in which surface conduction electron-emitting devices are arranged in parallel and a large number of rows are arranged in which both ends of each device are connected by wiring. (See, for example, Japanese Patent Application Laid-Open
31332).

In recent years, particularly in image forming apparatuses such as display apparatuses, flat panel display apparatuses using liquid crystal have become widespread instead of CRTs. However, since they are not self-luminous, they must have a backlight. There is a problem, and development of a self-luminous display device has been desired.

The above-mentioned surface conduction electron-emitting device has an advantage that a large number of devices can be arranged over a large area because of its simple structure and easy manufacture. Therefore, various applications have been made to take advantage of this feature.

[0016]

Next, a description will be given of a problem which has occurred in an image display apparatus which has been attempted using the above-described conventionally known surface conduction electron-emitting device.

For example, Japanese Patent Publication No. 45-31615 discloses a display device shown in FIGS. FIG. 35 shows a state viewed from the direction A in FIG. In this display device, a transverse current type electron emitter 2512 connected in series, and a strip-shaped transparent electrode 2514 so as to form a lattice with the electron emitter 2512 are arranged. Then, a glass plate 2513 having a small hole 2513 ′ is arranged between the lateral current type electron emitter 2512 and the transparent electrode 2514. Here, the glass plate 2513 is
3 'is a lateral current type electron emitter 2512 and a transparent electrode 2514
Are arranged so as to intersect with. In addition, hole 2
Gas is sealed in 513 ', and only the intersection of the lateral current type electron emitter 2512 emitting electrons and the transparent electrode 2514 to which the acceleration voltage E2 is applied emits light by gas discharge.

The above-mentioned Japanese Patent Publication No. 45-31615 does not provide a detailed description of the lateral current type electron emitter 2512. However, the materials (metal thin film, Nesa film) and neck portion 251 are described.
Since the structure 2 ′ is the same as the surface conduction electron-emitting device described in the section of the prior art, it is considered to be included in the category of the surface conduction electron-emitting device (the inventors used the present invention). The name of the surface conduction electron-emitting device is based on the description in the thin film handbook).

The problems of the above display device are listed below.

(1) In the above display device, electrons emitted from the lateral current type electron emitter are accelerated to collide with gas molecules to discharge the same. In addition, there is a problem that the discharge light emission luminance varies and the luminance varies even in the same pixel. The reason for this is that the discharge intensity is largely dependent on the state of the gas and the controllability is not good, and the output of the transverse current type electron-emitting device is under a pressure of about 15 mmHg as introduced in an experimental example. It is not always stable. For this reason, it is difficult for the display device to perform multi-tone display,
Uses were limited.

(2) In the above display device, the emission color can be changed by changing the type of gas to be sealed. However, generally, the visible light wavelength obtained by discharge emission is limited, and a wide range of colors is not always required. It cannot be expressed. In addition, the optimum pressure of discharge light emission often differs depending on the type of gas. Therefore, in order to colorize a single panel, it is necessary to change the type and pressure of the gas to be sealed for each hole, which makes the structure of the panel extremely difficult.
Further, it is not realistic to colorize the panel by stacking three panels in which different gases are sealed.

(3) In the above display device, the structure is complicated and the display is inexpensive because it is a combination of components such as a substrate on which a lateral current type electron-emitting device is formed, a transparent electrode, and a hole filled with gas. It was difficult to provide the device.
Further, as exemplified in the above publication, since the threshold voltage of the discharge light emission is as high as 35 V, it is necessary to use an electric element having a high withstand voltage in an electric circuit for driving the panel. This was causing the cost to increase.

When the conventional surface-conduction type electron-emitting device is used to discharge light in a gas to emit light and develop color, the above-described problems are encountered.

On the other hand, there is a method in which a phosphor is used as one of the components for emitting and coloring light in an image display device having a surface conduction electron-emitting device. However, the emission luminance of the phosphor has a certain characteristic with respect to the density of the irradiated current, and it is generally non-linear. The characteristics of each of the three primary colors (red (R), green (G), and blue (B)) are not the same. Therefore, when the irradiation current value is the same change amount for each of the RGB colors, the ratio of the emission luminance of each of the RGB colors before and after the change is general. That is, the color balance will be different.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems. In an image forming apparatus using a surface-conduction type electron-emitting device, the image forming apparatus has excellent gradation display characteristics and color shift when colorized. An object of the present invention is to provide an image forming apparatus and an image forming method that can easily realize control of color balance and the like.

[0026]

In order to achieve the above object, an image forming apparatus according to the present invention has the following arrangement. That is, (1) at least an electron beam generating source in which a plurality of surface conduction electron-emitting devices are arranged on a substrate and phosphors of three primary colors of red, green and blue which emit light by irradiation of the electron beam in a vacuum vessel. A modulating means for modulating an electron beam irradiating the phosphor on the basis of an image signal, wherein the modulating means comprises: It has a correcting means for correcting the non-linearity of the luminance.

An image forming method used in the color display device of the present invention is a method of forming an image by modulating an electron beam based on an image signal corrected in advance by the correction means.

(2) A first configuration of an electron beam generator that can be used in the color display device of the present invention is that a plurality of surface conduction electron-emitting devices are two-dimensionally arranged on a substrate, This is an electron beam generation source in which each element is connected in a matrix by directional wiring.

(3) In the color display device having the electron beam generating source of the first configuration, the modulating means is based on the gamma characteristic of (emission current intensity) to (applied voltage) of the surface conduction electron-emitting device. Correction means for correcting the image signal.

(4) The modulating means includes a correcting means for correcting an image signal based on a gamma characteristic of (emission intensity) of the phosphor (amount of irradiated electron beam).

(5) A second configuration of the electron beam generator which can be used in the color image display device of the present invention is a device group in which a plurality of surface conduction electron-emitting devices are arranged on a substrate along a row direction. And an electron beam generating source having an electrode row on the substrate or outside the substrate in which grid electrodes are arranged along a column direction substantially orthogonal to the row direction.

(6) In the color image display device having the electron beam generating source of the second configuration, the modulating means
A correction unit is provided for correcting the image signal based on the gamma characteristic of (emission intensity) vs. (emission electron beam amount) of the phosphor.

(7) The modulating means includes a correcting means for correcting the image signal based on the gamma characteristic of the (transmitted electron beam amount) of the grid electrode versus the (grid electrode applied signal).

(8) In the color image display apparatus according to the present invention, the first modulation method for modulating the electron beam irradiated on the phosphor is performed by a method of irradiating the phosphor with the electron beam based on the gamma-corrected image signal. This is a method of modulating the length of (pulse).

(9) In the color image apparatus of the first modulation method, the modulating means includes means for independently adjusting a modulation signal for modulating an electron beam for each color component (red, green, blue). .

(10) The first means of independently adjusting a modulation signal for modulating an electron beam for each color component (red, green, blue) is to individually compare each color component of a gamma-corrected image signal. Means for independently adjusting the relative relationship between the comparison reference of each comparator and the image signal.

(11) The second means for independently adjusting the modulation signal for modulating the electron beam for each color component (red, green, blue) is independent amplification for each color component of the gamma-corrected image signal. This means includes an amplifier having an adjustable rate and a comparator, and generates a modulated pulse by comparing the image signal amplified by the amplifier with a reference value by the comparator.

(12) The third means for independently adjusting the modulation signal for modulating the electron beam for each color component (red, green, blue) is to individually pulse each color component of the gamma-corrected image signal. This means has a width modulator and independently adjusts the frequency of the operation reference clock of each pulse width modulator.

(13) In the color image display device of the present invention, the second modulation method for modulating the electron beam irradiated on the phosphor is based on the current of the electron beam irradiated on the phosphor based on the gamma-corrected image signal. This is a method of modulating the amplitude.

(14) In the color image display device of the second modulation system, the modulation means independently adjusts a modulation signal for modulating the electron beam for each color component (red, green, blue). Prepare.

(15) The first means for independently adjusting the modulation signal for modulating the electron beam for each color component (red, green, blue) is that the level is individually adjusted for each color component of the gamma-corrected image signal. This means has a shifter and independently adjusts the shift amount of each level shifter.

(16) The second means for independently adjusting a modulation signal for modulating an electron beam for each color component (red, green, blue) is an amplifier individually for each color component of a gamma-corrected image signal. And a means for independently adjusting and amplifying the amplification factor of each amplifier.

According to the present invention, with the above arrangement, each color signal including gradation information is converted based on the light emission characteristics of a color light emitting panel having a surface conduction electron-emitting device. Then, by driving the light emitting panel based on the converted color signals, an image in which the color balance, the color misregistration and the like are corrected can be obtained.

Hereinafter, preferred embodiments of the image forming apparatus of the present invention will be described.

(Embodiment 1) A color display device according to the present invention comprises, in a vacuum vessel, at least an electron beam source in which a plurality of surface conduction electron-emitting devices are arranged on a substrate, and red and green light emitted by electron beam irradiation. , Blue primary color phosphor,
A modulating means for modulating an electron beam irradiating the phosphor based on the image signal, wherein the modulating means has a correcting means for correcting gamma of the image signal. .

[0046] Here, the vacuum container is transparent face plate and a bottom plate forming the phosphors of three primary colors on the inner surface, is configured of a side wall, the container interior, for example 10 ^-5 [t
orr] or 10 ^-7 [torr]. In other words, this device is a device with gas discharge described in the problem of the prior art, and directly irradiates the three primary color phosphors with an electron beam flying in a vacuum.
Stable light emission can be obtained.

The image forming method used in the color display device of the present invention is a method for forming an image by modulating an electron beam based on an image signal whose gamma has been corrected in advance by the correction means.

That is, for example, NTSC system or PAL
Of various image signals, such as the video, SECAM, and high-definition televisions, in advance according to the display characteristics (gamma characteristics) of the display pulse provided with the surface-conduction emission element in the electron source section, and the corrected image By modulating the display panel based on the signal, a display image faithful to the original image is obtained.

An electron source in which a plurality of surface conduction electron-emitting devices of the color display device of the present invention are arranged will be described in embodiments 2 and 5.

The means for correcting in accordance with the gamma of the display panel will be described in embodiments 3, 4, 6, and 7.

The method of modulating the electron beam will be described in embodiments 8 and 9.

(Embodiment 2) A first configuration of an electron beam generating source that can be used in the color display device of the present invention is that a plurality of surface conduction electron-emitting devices are two-dimensionally arranged on a substrate, This is an electron beam generation source in which elements are connected in a matrix by column-directional wiring.

More specifically, M × N (M and N are positive integers) matrix-shaped surface-conduction emission devices are formed on an electrically insulating substrate, and N row-direction wirings and M The column-directional wirings are connected in a matrix, and a drive signal is applied to the wirings to emit electron beams from desired surface conduction electron-emitting devices. In the present electron beam generation source, the intensity or charge amount of the electron beam emitted from the surface conduction electron-emitting device can be easily controlled by changing the amplitude or the time length of the drive signal.

(Embodiment 3) In the color display device provided with the electron beam generating source of the first configuration, the modulating means comprises:
(Emission current intensity) vs. (Applied voltage) of surface conduction type emission device
Correction means for correcting the image signal based on the gamma characteristic of

The emission current intensity of the surface conduction electron-emitting device generally has a threshold value with respect to an applied voltage, and non-linearly increases with an increase in voltage exceeding the threshold value. Therefore, when the surface conduction electron-emitting device is driven without applying any correction to the image signal to irradiate the phosphor with an electron beam, only a voltage below the threshold value is applied to the device for a certain level of the image signal. There is a problem in that no light is emitted because no voltage is applied, and that the luminance sharply changes at a certain level or higher of the image signal.

In the color image display device according to the present invention, the image signal is corrected in advance in consideration of the characteristic electron beam output characteristic (gamma characteristic) of the surface conduction electron-emitting device, so that the original image is more faithful. The display is realized.

(Embodiment 4) In the color display device having the electron beam generating source of the first configuration, the modulating means is provided with a gamma characteristic of (emission intensity) vs. (irradiation electron beam amount) of the phosphor. Correction means for correcting the image signal based on the correction signal.

That is, each of the red, green, and blue phosphors has a non-linear change in emission intensity with respect to the amount of electron beam irradiated, and has a characteristic curve different for each color. Therefore, when the phosphor is irradiated with the electron beam without correcting the image signal, there is a problem that the luminance and the color are shifted from the original image.

In the color image display device according to the present invention, the image signal is corrected in advance in consideration of the light emission characteristics of the phosphor of each color, thereby realizing a more accurate display of the original image.

It should be noted that whether the correction means used in the above-described modes 3 and 4 handles image information as analog values,
Alternatively, it may be one of those handled as digital values.

(Embodiment 5) A second configuration of the electron beam generator that can be used in the color image display device of the present invention is as follows.
A device group in which a plurality of surface conduction electron-emitting devices are arranged on a substrate along a row direction, and an electrode row on a substrate or an electrode array on which grid electrodes are arranged outside a substrate along a column direction substantially orthogonal to the row direction. An electron beam source.

That is, M × N (M and N are positive integers) matrix-shaped surface-conduction emission devices are formed on an electrically insulating substrate, and those arranged in the row direction are electrically connected. And N rows of element rows in each of which M elements are wired in parallel.

By appropriately applying a drive signal to the wiring, M electron beams can be simultaneously output from an arbitrary element row.

On the insulating substrate or outside the substrate, M grid electrodes are provided along the column direction orthogonal to the row direction. Each grid electrode corresponds to each surface conduction type emission element. The formed electron beam transmission port is formed.

By appropriately applying a voltage signal to the grid electrode, it is possible to control the transmission amount of the electron beam output from the surface conduction electron-emitting device.

That is, in the present electron beam generating source, the intensity or the charge amount of the electron beam passing through the grid electrode can be easily controlled by changing the amplitude or the time length of the signal applied to the grid electrode. Can be.

(Embodiment 6) In the color image display device provided with the electron beam generator of the second configuration, the modulating means is based on the gamma characteristic of (emission intensity) vs. (irradiation electron beam amount) of the phosphor. Correction means for correcting the image signal.

That is, each of the red, green, and blue phosphors has a non-linear change in emission intensity with respect to the amount of electron beam irradiated, and also has a characteristic curve different for each color. Therefore, when the phosphor is irradiated with the electron beam without correcting the image signal, there is a problem that the luminance and the color are shifted from the original image. In the color image display device according to the present invention, by performing correction on the image signal in advance in consideration of the emission characteristics of the phosphor of each color,
The display is more faithful to the original image.

(Aspect 7) Further, the modulating means comprises (transmitted electron beam amount) of the grid electrode versus (grid electrode applied signal).
Correction means for correcting the image signal based on the gamma characteristic of

That is, in an electron beam source in which a surface conduction electron-emitting device and a grid electrode are combined, the intensity of the electron beam transmitted through the grid electrode has a threshold with respect to the voltage applied to the grid electrode. It changes non-linearly for voltages above the threshold. Of course, the characteristic curve varies depending on the material and shape of the surface conduction electron-emitting device and the shape and position of the grid electrode, but shows characteristics different from those of a generally well-known electron beam source combining a hot cathode and a grid electrode.

Accordingly, when the surface conduction electron-emitting device and the grid electrode are driven to irradiate the phosphor with an electron beam without correcting the image signal, the grid electrode is not applied to the image signal below a certain level. There is a problem that no light is emitted because only a voltage lower than the threshold value is applied, and that the luminance sharply changes at a certain level of the image signal.

In the color image display device according to the present invention, the image signal is corrected in advance in consideration of the characteristic electron beam transmission characteristic of the electron beam source having the combination of the surface conduction electron-emitting device and the grid electrode. The display is more faithful to the original image.

It should be noted that whether the correction means used in the above-described modes 6 and 7 handles image information as analog values,
Alternatively, it may be one of those handled as digital values.

(Embodiment 8) In the color image display apparatus of the present invention, the first modulation method for modulating the electron beam irradiated on the phosphor is to irradiate the phosphor with the electron beam based on the gamma-corrected image signal. This method modulates the length of time (pulse).

The means for modulating the length of time for irradiating the phosphor is more specifically for modulating the signal applied to the electron beam source according to the luminance level of the gamma-corrected image information. In the electron beam source of the second aspect, the length of the drive signal applied to the surface conduction electron-emitting device is modulated, and in the electron beam source of the fifth aspect, the length of the voltage signal applied to the grid electrode is modulated.

(Aspect 9) In the color image apparatus of the first modulation method, the modulating means independently adjusts a modulation signal for modulating an electron beam for each color component (red, green, blue). Means.

That is, for the electron beam sources provided corresponding to the phosphors of each color (red, green, blue), adjustment means are provided so that the irradiation time of the electron beam can be changed independently for each color. is there.

The adjusting means is set by the manufacturer so as to obtain an appropriate color balance at the time of manufacturing the color image display device, but it is desirable that the setting means be changed so that the user can change the setting as desired thereafter. .

(Embodiment 10) The first means of independently adjusting a modulation signal for modulating an electron beam for each color component (red, green, blue) is individually for each color component of a gamma-corrected image signal. This is means for providing comparators and independently adjusting the relative relationship between the comparison reference of each comparator and the image signal.

That is, each color component of the image signal is formed into a sawtooth waveform whose amplitude changes according to the luminance, and these are compared with a reference value to form a pulse width modulation signal whose pulse width changes according to the luminance. Convert. At that time, a comparator is provided individually for each color component so that the reference value can be set or changed independently of each other. In addition, the adjusting means may be any as long as it can adjust the relative relationship between the sawtooth waveform and the reference value for each color component. In some cases, a bias is applied to the sawtooth waveform for each color component. Means may be provided so that the bias amount can be adjusted independently.

(Aspect 11) A second means of independently adjusting a modulation signal for modulating an electron beam for each color component (red, green, blue) is independent for each color component of a gamma-corrected image signal. Providing an amplifier and comparator with adjustable amplification factor,
This is means for generating a modulated pulse by comparing the image signal amplified by the amplifier with a reference value by a comparator.

It should be noted that whether the adjusting means used in the above-described embodiments 10 and 11 handles signals as analog values,
Alternatively, it may be constituted by any electric circuit which is handled as a digital value.

(Aspect 12) A third means of independently adjusting a modulation signal for modulating an electron beam for each color component (red, green, blue) is individually for each color component of a gamma-corrected image signal. This is means for providing a pulse width modulator and independently adjusting the frequency of the operation reference clock of each pulse width modulator.

That is, for example, a counter which counts the number of reference clocks, a coefficient value of the counter is compared with the data of the image signal, and a pulse width modulation configured to generate a pulse until both values become equal. The device is configured so that the frequency of the reference clock can be adjusted independently for each color component.

(Aspect 13) In the color image display device of the present invention, the second device for modulating the electron beam irradiated on the phosphor is used.
Is a method of modulating the current amplitude of an electron beam irradiating a phosphor based on a gamma-corrected image signal.

That is, the method of modulating the time length of irradiating the electron beam described in the above mode 8 is different from the method of modulating the amplitude of the voltage signal applied to the electron beam source according to the luminance level of the image information. For example, in the electron beam source of the second aspect, the amplitude of the driving voltage applied to the surface conduction electron-emitting device is modulated, and in the electron beam source of the fifth aspect, the amplitude of the voltage signal applied to the grid electrode is changed. Modulate.

(Aspect 14) In the color image display device of the second modulation method, the modulation means independently adjusts a modulation signal for modulating an electron beam for each color component (red, green, blue). Is provided.

That is, the electron beam sources provided corresponding to the phosphors of the respective colors (red, green, blue) have adjusting means so that the current amplitude of the electron beam can be independently changed for each color.

The adjusting means is set by the manufacturer so that an appropriate color balance can be obtained at the time of manufacturing the color image display device. However, it is preferable that the adjusting means be configured so that the user can change the setting as desired thereafter. .

(Aspect 15) In the above aspect 14, the modulation signal for modulating the electron beam is converted into each color component (red, green,
The first of the means for independently adjusting each blue component is a means for individually adjusting a level shifter for each color component of the gamma-corrected image signal and independently adjusting the shift amount of each level shifter.

That is, when appropriately amplifying the image signal and modulating the drive signal of the electron beam source, the image signal after gamma correction or the signal after amplifying it is
A level shifter is provided for each color component to adjust the shift amount.

(Aspect 16) In the above aspect 14, the second means of independently adjusting a modulation signal for modulating an electron beam for each color component (red, green, blue) is a gamma-corrected image signal. This means has an amplifier for each color component individually, and independently adjusts and amplifies the amplification factor of each amplifier.

Of the modes described above, the modulation method of mode 8 or mode 13 can be used in the electron beam generating source of mode 2, and the mode 8 or mode 13 can be similarly applied to the electron beam generating source of mode 5. Thirteen modulation schemes are possible.

It is effective to carry out either one of the embodiments 3 and 4, but it is effective to carry out both of them in some cases, so that a more faithful display may be possible. It is preferred to do so.

Although the above-described embodiments 6 and 7 are effective even when used alone, there is a case where even more faithful display is possible by performing both together.
It is preferable to perform both.

Further, the above-mentioned embodiments 10 and 11
There was an effect when performed alone, but when combined, the image quality was greatly improved.

The above embodiments 15 and 16
Although it is effective to use them alone, it is sometimes effective to display even more faithfully by performing both together, and it is preferable to perform both together.

The surface conduction electron-emitting device used for the electron beam generating source in carrying out the present invention is not particularly limited with respect to the structure, material, manufacturing method and the like. It is more preferable because it is also excellent.

(Embodiment of Surface Conduction Electron-Emitting Element) A basic structure and a manufacturing method of a surface conduction electron-emitting element which is suitable for the present invention will be described.

The basic configuration of the surface conduction electron-emitting device according to the present invention includes two configurations, a planar type and a vertical type.

First, the flat surface conduction electron-emitting device will be described.

FIGS. 1A and 1B are a schematic plan view and a sectional view, respectively, showing the configuration of a basic surface conduction electron-emitting device according to the present invention. The basic configuration of the device according to the present invention will be described with reference to FIG.

In FIG. 6, 1 is a substrate, 5 and 6 are device electrodes, 4 is a thin film including an electron emitting portion, and 3 is an electron emitting portion.

Examples of the substrate 1 include quartz glass, glass having a reduced impurity content such as Na, blue plate glass, a glass substrate obtained by laminating SiO ₂ formed on a blue plate glass by sputtering or the like, and ceramics such as alumina. Can be

The material of the opposing device electrodes 5 and 6 may be any material as long as it has conductivity. For example, Ni, Cr, Au, Mo, W, Pt,
Metals or alloys such as Ti, Al, Cu, Pd and Pd, A
Printed conductors composed of a metal such as u, RuO ₂ , Pd-Ag or the like and a metal oxide and glass, transparent conductors such as In ₂ O ₃ —SnO ₂ , and semiconductor conductor materials such as polysilicon are exemplified. .

The element electrode interval L1 is from several hundred angstroms to several hundred micrometers, and the photolithography technique, which is the basis of the element electrode manufacturing method, that is, the performance of an exposing machine and the etching method, etc. Voltage and the electric field strength that can emit electrons.
Preferably, it is several micrometers to several tens of micrometers.

The element electrode length W1 and the film thickness d of the element electrodes 5 and 6 are appropriately designed in consideration of the resistance of the electrodes and the arrangement of a large number of arranged electron sources. ,
Hundreds of micrometers rather than a few micrometers,
The film thickness d of the device electrodes 5 and 6 is several hundred angstroms to several micrometers.

Opposing element electrode 5 provided on substrate 1
The thin film 4 including the electron-emitting portions disposed between the device electrodes 6 and on the device electrodes 5 and 6 includes the electron-emitting portions 3.
In addition to the case shown in (b), there is a case where it is not installed on the device electrodes 5 and 6. That is, this is a case where the thin film 2 for forming an electron emission portion and the device electrodes 5 and 6 facing each other are laminated on the substrate 1 in this order. Further, the opposing element electrode 5
In some cases, the space between the device electrode 6 and the device electrode 6 may function as an electron emitting portion depending on the manufacturing method. The thin film 4 including the electron emitting portion
Has a thickness of preferably several Angstroms to several thousand Angstroms, particularly preferably 10 Angstroms to 500 Angstroms.
6, the resistance value between the electron-emitting portion 3 and the device electrodes 5 and 6, the particle size of the conductive fine particles of the electron-emitting portion 3, the energization processing conditions described later, and the like are appropriately set.
The resistance value indicates a sheet resistance value of 10 7 Ω / □ to 10 7.

Pd, Pt, Ru, Ag, A, Pd, Pt, Ru, Ag
u, Ti, In, Cu, Cr, Fe, Zn, Sn, T
a, W, Pb and other metals, PdO, SnO ₂ , In ₂ O ₃ ,
Oxides such as PbO and Sb ₂ O ₃ , HfB ₂ , ZrB ₂ and La
Borides such as B ₆ , CeB ₆ , YB ₄ , GdB ₄ , TiC, Z
carbides such as rC, HfC, TaC, SiC, WC, Ti
It is composed of nitrides such as N, ZrN, HfN, semiconductors such as Si and Ge, and carbon fine particles.

The fine particle film described here is a film in which a plurality of fine particles are gathered, and has a fine structure not only in a state in which the fine particles are individually dispersed and arranged, but also in a state in which the fine particles are adjacent to each other or overlap each other (an island). (Including the shape). The particle size of the fine particles is from several Angstroms to several thousand Angstroms, preferably from 10 Angstroms to 200 Angstroms.

The electron-emitting portion 3 is preferably from several angstroms to several hundred angstroms, particularly preferably
It is composed of a number of conductive fine particles having a particle size of 10 to 500 angstroms and depends on the manufacturing method such as the thickness of the thin film 64 including the electron-emitting portion and the energization processing conditions to be described later, and is set as appropriate. The material forming the electron emitting portion 63 is similar to some or all of the elements of the material forming the thin film 4 including the electron emitting portion.

Various methods are conceivable as a method for manufacturing the electron-emitting device having the electron-emitting portion 3. One example is shown in FIG. Reference numeral 2 denotes a thin film for forming an electron emitting portion, for example, a fine particle film.

Hereinafter, the manufacturing method will be described step by step with reference to FIGS.

1) After sufficiently cleaning the substrate 1 with a detergent, pure water, and an organic solvent, depositing an element electrode material by a vacuum evaporation method, a sputtering method, or the like, and depositing the element on the surface of the insulating substrate 1 by a photolithography technique. Electrodes 5 and 6 are formed (FIG. 2A).

2) An organic metal solution is applied between the device electrode 5 and the device electrode 6 provided on the substrate 1 on the substrate on which the device electrodes 5 and 6 are formed, and the organic metal thin film is left. To form In addition, the organic metal solution refers to the Pd,
Ru, Ag, Au, Ti, In, Cu, Cr, Fe, Z
It is a solution of an organic compound containing a metal such as n, Sn, Ta, W, Pb as a main element. Thereafter, the organic metal thin film is heated and baked, and is patterned by lift-off, etching or the like to form the thin film 2 (FIG. 2B). Here,
Although the method has been described using the method of applying an organic metal solution, the present invention is not limited to this, and may be formed by a vacuum evaporation method, a sputtering method, a chemical vapor deposition method, a dispersion coating method, a dipping method, a spinner method, or the like.

3) Subsequently, when an energization process called forming is applied to the device electrodes 5 and 6 by applying a pulsed voltage or an energization process with a voltage increase by a power supply (not shown), the structure of the thin film 2 changes at the site. The formed electron-emitting portion 3 is formed (FIG. 2C). By this energization process, the thin film 2 for forming an electron emission portion is locally broken, deformed or deteriorated, and a portion having a changed structure is called an electron emission portion 3. The present inventors have observed that the electron-emitting portion 3 is made of conductive fine particles as described above. FIG. 3 shows a voltage waveform in the case of applying a pulse in the forming process.

In FIG. 3, T1 and T2 are the pulse width and pulse interval of the voltage waveform, T1 is 1 to 10 milliseconds, T2 is 10 to 100 milliseconds, and the peak value of the triangular wave is appropriately selected. And the forming process is 10 ⁻⁵ t
Under a vacuum atmosphere of about orr, the voltage was applied for several tens of seconds to several tens of minutes.

In forming the above-described electron-emitting portion,
Although the forming process is performed by applying a triangular wave pulse between the electrodes of the element, the waveform applied between the electrodes of the element is not limited to the triangular wave, and a desired waveform such as a rectangular wave may be used. The high value, pulse width, pulse interval and the like are not limited to the above-mentioned values, and a desired value is selected according to the resistance value of the thin film 2 and the like so that the electron-emitting portion is favorably formed.

The electrical processing after the forming is performed in the measurement and evaluation apparatus shown in FIG. The measurement evaluation device will be described below.

FIG. 4 is a schematic configuration diagram of a measurement and evaluation device for measuring the electron emission characteristics of the device having the configuration shown in FIG. In FIG. 4, reference numeral 1 denotes a base, 5 and 6 denote device electrodes, 4 denotes a thin film including an electron-emitting portion, and 3 denotes an electron-emitting portion. Reference numeral 41 denotes a voltage Vf (hereinafter referred to as an element voltage V
f)), and 40 is a device electrode 5,
An ammeter 44 for measuring a device current If flowing through the thin film 4 including an electron emission portion between 6, an anode electrode 44 for capturing an emission current Ie emitted from the electron emission portion of the device;
Reference numeral 43 denotes a high-voltage power supply for applying a voltage to the anode electrode 44, and reference numeral 42 denotes an ammeter for measuring an emission current Ie emitted from the electron emission section 3 of the device.

In measuring the device current If and the emission current Ie of the electron-emitting device, the power supply 41 is connected to the device electrodes 5 and 6.
And an ammeter 40, and an anode 44 connected to a power supply 43 and an ammeter 42 is disposed above the electron-emitting device. In addition, the present electron-emitting device and the anode electrode 44
Is installed in a vacuum device, and the vacuum device is equipped with an exhaust pump (not shown) and equipment required for a vacuum device of a vacuum gauge, so that the element can be measured and evaluated under a desired vacuum. .

The voltage of the anode electrode ranges from 1 kV to 10 kV.
kV, the distance H between the anode electrode and the electron-emitting device is 2 mm
It was measured in a range of ８8 mm.

FIG. 5 shows a typical example of the relationship between the emission current Ie, the device current If, and the device voltage Vf measured by the measurement and evaluation apparatus shown in FIG. FIG. 5 shows the emission current I
Since e is much smaller than the element current If, it is shown in arbitrary units. As is clear from FIG. 5, the electron-emitting device has three characteristics with respect to the emission current Ie.

First, when an element voltage higher than a certain voltage (referred to as a threshold voltage, Vth in FIG. 5) is applied to the surface conduction electron-emitting device, the emission current Ie sharply increases,
On the other hand, below the threshold voltage Vth, the emission current Ie is hardly detected. That is, it is a nonlinear element having a clear threshold voltage Vth with respect to the emission current Ie.

Second, since the emission current Ie depends on the device voltage Vf, the emission current Ie can be controlled by the device voltage Vf.

Third, the emission charge captured by the anode electrode 44 depends on the time during which the device voltage Vf is applied. That is, the amount of charge captured by the anode electrode 44 can be controlled by the time during which the device voltage Vf is applied.

An example of the characteristic in which the element current If monotonically increases with respect to the element voltage Vf (referred to as the MI characteristic) is shown in the solid line in FIG.
May exhibit a voltage-controlled negative resistance (referred to as VCNR characteristic) characteristic in some cases. (The broken line in FIG. 5) It is considered that the characteristics of these element currents depend on the manufacturing method and the measurement conditions at the time of measurement. Also in this case, the electron-emitting device has the above-mentioned three characteristics.

In a surface conduction electron-emitting device in which conductive fine particles are dispersed in advance, a part of the above-described basic device structure or basic manufacturing method may be changed.

Next, a vertical surface conduction electron-emitting device which is another surface conduction electron-emitting device according to the present invention will be described. FIG. 6 is a schematic drawing showing the configuration of a basic vertical surface conduction electron-emitting device.

In FIG. 6, 61 is a substrate, 65 and 66 are device electrodes, 64 is a thin film including an electron emitting portion, 63 is an electron emitting portion, and 21 is a step forming portion.

The substrate 61, the device electrodes 65 and 66, the thin film 64 including the electron-emitting portion, and the electron-emitting portion 63 are made of the same material as that of the above-mentioned flat surface conduction type electron-emitting device. The step forming portion 21 and the thin film 64 including the electron emitting portion, which characterize the surface conduction electron-emitting device, will be described in detail. The step forming portion 21 is made of an insulating material such as SiO ₂ formed by a vacuum deposition method, a printing method, a sputtering method, or the like, and the thickness of the step forming portion 21 is the same as that of the above-mentioned planar surface conduction type electron. Corresponding to the element electrode interval L1 of the emitting element, it is several hundreds of angstroms to several tens of micrometers, and is set by the manufacturing method of the step forming portion and the voltage applied between the element electrodes. A few micrometers.

The thin film 64 including the electron emitting portion is formed on the device electrode 6
After the steps 5 and 66 and the step forming portion 21 are formed, they are stacked on the device electrodes 65 and 66 for formation. In addition, the thickness of the thin film 64 including the electron-emitting portion often differs between the thickness at the step portion and the thickness of the portion stacked on the device electrodes 65 and 66 depending on the manufacturing method. Generally, the thickness of the step portion is small. Although the electron emitting portion 64 is shown in a straight line in the step forming portion 21 in FIG. 2, the shape and the position are not limited to this, but depend on the forming conditions, forming conditions and the like.

The basic structure and manufacturing method of the surface conduction electron-emitting device have been described above. According to the concept of the present invention, if the surface conduction electron-emitting device has three characteristics,
The present invention is not limited to the above-described configuration and the like, and can be applied to an image forming apparatus such as a display device according to the present invention described later.

[0134]

(Embodiment 1) First, the electron source used in the image forming apparatus of the present invention will be specifically described, then the configuration of a display panel will be described, and then a method of displaying a color image will be described.

<Explanation of the Electron Source of the Present Embodiment> FIG. 7 is a plan view of a part of the electron source. FIG. 8 is a sectional view taken along the line AA 'in the figure. Further, FIGS. 9A to 9H and FIGS. 10A to 10D show a process for manufacturing the electron source of the present embodiment. 7 to 10, the same components are denoted by the same reference numerals.

In FIG. 7, reference numeral 272 denotes an X-direction wiring, which is composed of m wirings Dx1 to Dxm. 273
Denotes a Y-direction wiring, which is composed of n wirings DY1 to DYn.

In FIG. 8, reference numeral 271 denotes an insulating substrate;
Reference numeral 2 denotes an X-direction wiring (also referred to as a lower wiring), and 273 denotes a Y-direction wiring (also referred to as an upper wiring). Reference numeral 274a denotes a thin film for forming an electron-emitting portion, and an electron-emitting portion is formed by performing a forming process, thereby forming a surface conduction electron-emitting device 274. 275a and b are device electrodes, 276 is a correlated insulating layer,
Reference numeral 277 denotes a contact hole for making electrical connection between the element electrode 275a and the X-direction wiring 272.

Next, a method of manufacturing the electron source of this embodiment will be described with reference to FIG.
A specific description will be given in the order of steps with reference to FIGS.

[Step-a] (Refer to FIG. 9A) Cr on a thickness of 50 Å and Au on a thickness of 6000 Å are sequentially laminated on a substrate 271 made of cleaned blue glass by vacuum evaporation. Thereafter, a photoresist (AZ1370 Hoechst) is spin-coated with a spinner and baked. Thereafter, the photomask image is exposed and developed to form a resist pattern for the X-directional wiring 272, and the Au / Cr volume film is wet-etched to form the X-directional wiring 272 having a desired shape.

[Step-b] (see FIG. 9B) Next, an interlayer insulating layer 276 made of a silicon oxide film having a thickness of 1.0 μm.
Is deposited by RF sputtering.

[Step-c] (See FIG. 9 (c)) Step-b
A photoresist pattern for forming a contact hole 277 is formed in the silicon oxide film (interlayer insulating layer 276) deposited by the method described above, and the interlayer insulating layer 276 is etched using the photoresist pattern as a mask to form a contact hole 277. For the etching, for example, RIE (React
ive Ion Etchihg) method.

[Step-d] (see FIG. 9D)
A pattern to be a gap G between the device electrode 275 and the device electrode is formed by a photoresist (RD-2000N-41: manufactured by Hitachi Chemical Co., Ltd.), and a Ti film having a thickness of 50 Å and a Ni film having a thickness of 1000 Å are formed by a vacuum deposition method.
Are sequentially deposited. The photoresist pattern is dissolved with an organic solvent, and the Ni / Ti deposited film is lifted off to form device electrodes 275a and 275b having a gap G between the device electrodes. Here, the gap G between the device electrodes was 2 μm.

[Step-e] (See FIG. 9 (e)) After forming a photoresist pattern of a Y-directional wiring on the device electrode 275b, a 50 angstrom Ti, 50 angstrom thick
Au of 00A is sequentially vacuum-deposited, and unnecessary portions are removed by lift-off to form a Y-direction wiring 273.

[Step-f] (see FIG. 9 (f)) FIG.
A part of a plan view of a mask of the thin film 274a formed in this step is shown in FIG. This mask has an inter-electrode gap G and an opening in the vicinity thereof. A Cr film 278 having a thickness of 1000 angstroms is deposited and patterned by vacuum evaporation. Then, an organic Pd (ccp4230 manufactured by Okuno Pharmaceutical Co., Ltd.) was applied thereon by a spinner, and then 300 ° C.
For 10 minutes to form a thin film 274a for forming an electron emission portion made of Pd. The electron-emitting-portion-forming thin film 274a thus formed was composed of fine particles containing Pd as a main element, and had a thickness of 100 angstroms and a sheet resistance of 5 × 10 ⁴ Ω / □.
Note that the fine particle film described here is a film in which a plurality of fine particles are aggregated as described above, and has a fine structure not only in a state where the fine particles are individually dispersed and arranged, but also in a state where the fine particles are adjacent to each other or overlapped. It refers to a film in a state (including an island shape), and the particle size refers to a diameter of a fine particle whose particle shape can be recognized in the state.

[Step-g] (See FIG. 9 (g)) Cr film 2
78 and the thin film 274a are wet-etched with an acid etchant to form a desired pattern.

[Step-h] (see FIG. 9H) A pattern is formed such that a resist is applied to portions other than the contact hole 277, and 50 Å thick Ti and 1.1 μm thick Au are formed by vacuum evaporation. Are sequentially deposited. After embedding the contact hole 277 with Au, unnecessary portions are removed by lift-off.

Through the above steps, the X-direction wiring 272, the interlayer insulating layer 276, the Y-direction wiring 273, the device electrodes 275a and 275b, and the electron emission portion forming thin film 274a are formed on the same substrate.
Are formed to form a matrix wiring substrate of the surface conduction electron-emitting device. Note that the above process is an example using a technique such as thin film, photolithography, and etching. However, the present invention is not limited to this. For example, printing as a wiring forming technique may be used, or other various techniques may be used. .

<Description of Image Forming Apparatus of the Present Embodiment> Next, an example of an image forming apparatus using the electron source created as described above will be described. The image forming apparatus is shown in FIG.
1 and FIG.

After fixing the electron source on which a large number of planar surface conduction electron-emitting devices are formed as described above on the rear plate 281, a face plate 286 (glass substrate 283) is placed 5 mm above the insulating substrate 271. Fluorescent film 2 on inner surface
84 and a metal back 285 are formed) via a support frame 282. Face plate 28
6, frit glass was applied to the joint between the support frame 282 and the rear plate 281 and sealed by baking for 10 minutes or more at 400 ° C. to 500 ° C. in the air or a nitrogen atmosphere. Also, the insulating substrate 28 on the rear plate 281
The fixing of the insulating substrate 271 to 1 was also performed with frit glass.

In FIG. 12, the fluorescent film 284 is made of only a fluorescent material in the case of monochrome, but in this embodiment, the fluorescent material adopts a stripe shape, a black stripe is formed first, and each color (red) is formed in the gap. , Green, blue) phosphor was applied to form a fluorescent film 284. As the material for the black stripe, a material mainly containing graphite, which is generally used, was used.

In this embodiment, a slurry method was used as a method of applying a phosphor onto the glass substrate 283. Also, the fluorescent film 2
A metal back 285 is usually provided on the inner surface side of 84. The metal back was manufactured by performing a smoothing process (usually called filming) on the inner surface of the fluorescent film after the fluorescent film was manufactured, and then vacuum-depositing Al.

The face plate 286 may be provided with a transparent electrode (not shown) on the outer surface side of the fluorescent film 284 in order to further enhance the conductivity of the fluorescent film 284. In this embodiment, however, only a metal back is used. Omitted because sufficient conductivity was obtained.

Further, when the above-mentioned sealing was performed, in the case of color, each phosphor and the electron-emitting device had to correspond to each other, so that sufficient alignment was performed.

The atmosphere in the glass container completed as described above is evacuated by a vacuum pump through an exhaust pipe (not shown), and reaches a sufficient degree of vacuum. Then, a voltage was applied between the device electrodes, and the above-described forming process was performed on the thin film 274 to form an electron-emitting portion.

The voltage waveform in the forming process is as shown in FIG. 3 described above. In this embodiment, the following conditions were used.

In FIG. 3, T1 and T2 are the pulse width and pulse interval of the voltage waveform. In this embodiment, T1 is 1 millisecond,
T2 is set to 10 milliseconds, the peak value of the triangular wave (the peak voltage at the time of forming) is set to 5 V, and the forming process is performed by about 1
This was performed for 60 seconds in a vacuum atmosphere of × 10 ^-6 torr. The electron-emitting portion thus prepared was in a state in which fine particles containing palladium as a main component were dispersed and arranged, and the fine particles had an average particle size of 30 angstroms.

Next, after the forming of all the surface conduction electron-emitting devices is completed, the exhaust pipe (not shown) is welded by heating with a gas burner at a degree of vacuum of about 1 × 10 ⁻⁶ torr to form an envelope. Was sealed.

Finally, in order to maintain the degree of vacuum after sealing,
Getter processing was performed. This is a process in which a getter disposed at a predetermined position (not shown) in the image display device is heated by a heating method such as high-frequency heating immediately before sealing to form a vapor-deposited film. The getter was mainly composed of Ba or the like.

In the image display device of the present invention completed as described above, the scanning signals and the modulation signals are respectively supplied to the respective electron-emitting devices through signal terminals (not shown) through the external terminals DX1 to DXm and DY1 to DYn. By applying the voltage, electrons are emitted, a high voltage of several kV or more is applied to the metal back 285 through the high voltage terminal Hv, and the electron beam is accelerated, collides with the fluorescent film 284, and is excited and emitted to display an image. .

The configuration described above is a schematic process necessary for producing an image display device.
The detailed part is not limited to the contents described above, and is appropriately selected so as to be suitable for the use of the image display device.

<Regarding Color Control of Color Image in This Embodiment> FIG. 13 is a circuit block diagram for realizing control of a color signal having a gradation according to this embodiment.

In FIG. 13, reference numeral 311 enclosed by a dotted line denotes a demodulation unit which detects and amplifies a carrier wave of a certain frequency modulated by the video and color signals. 31 surrounded by dotted line
Reference numeral 2 denotes a video interface unit which receives a video signal (digital signal) from a computer or the like and converts it into an analog signal. A gamma correction circuit 313 corrects an image signal according to an applied voltage-emission current characteristic of the surface conduction electron-emitting device. A matrix circuit 314 converts the three components of the NTSC signal, the Y signal, the I signal, and the Q signal, into the three components of the color signal, the R signal, the G signal, and the B signal. The matrix circuit 314 is an important circuit in a conventional television circuit. This matrix circuit 31
A general example of the coefficient of 4 is shown in FIG. The way of determining the coefficient is generally determined by the coefficient of a matrix circuit when converting a certain image into an NTSC signal using a television camera. However, this coefficient is not determined uniquely and can be changed by various characteristics on the image receiving side. A gamma correction circuit 315 corrects the RGB signals output from the gamma correction circuit 313 according to the light emission characteristics of the phosphor.

A pulse width modulation circuit 316 converts the voltage-modulated RGB signal output from the gamma correction circuit 315 into a pulse width modulation signal. However, in the first embodiment, the pulse modulation circuit 316 is not used, and the voltage modulation signal output from the gamma correction circuit 315 is controlled by the control circuit 317.
Is directly input to A control circuit 317 generates various signals for driving the panel 320 based on the voltage-modulated RGB signals, and outputs the generated signals to the data driver 318 and the scanning driver 319. A data driver 318 applies a drive signal to each column wiring. 319
Denotes a scanning driver, which applies a drive signal to each row method wiring. Reference numeral 320 denotes a panel having the above-mentioned electron source.

As the demodulation unit 311, a circuit similar to that used in a conventional television circuit can be used.

The demodulation unit 311 is a circuit necessary for converting an NTSC signal in a television broadcast into a predetermined signal (in this case, each signal of Y, I, and Q). Therefore, in the case of a signal according to a method other than the NTSC signal, another circuit configuration is naturally used. For example,
Even if the input signal is a certain color signal component (for example, a data signal (CAD data or the like) by a computer, a signal from a television camera, or the like), it may not be too much.
In this case, an image signal is fetched not from the demodulation unit 311 but from the video interface unit 312. In this case, since the signal is converted into an RGB analog signal in the interface unit 312, the matrix circuit 314 is controlled so as not to operate.

As a configuration for realizing the color signal control method of this embodiment, a first configuration in which color signals are controlled by a gamma correction circuit and a matrix circuit, and a pulse width modulation circuit 316
And the second configuration for performing color signal control. The second configuration will be described in the second and third embodiments.

In the first configuration of this embodiment, the matrix circuit 314 is applied to an image display device using a surface conduction electron-emitting device. That is, the matrix circuit 31
The circuit constant of 4 is determined in consideration of the electrical characteristics of the surface-conduction electron-emitting device and the emission characteristics of the phosphor that is a component of the image display device, thereby realizing control of a color signal having a gradation. It is.

As described above, FIG. 5 shows typical electric characteristics of the surface conduction electron-emitting device which is a component of the color image display device using the surface conduction electron-emitting device of this embodiment. FIG. 15 is a diagram showing the light emission characteristics of the phosphor which is a component of the image forming apparatus of this embodiment. As shown in FIG. 5, the electron emission characteristics of the surface conduction electron-emitting device have nonlinear characteristics. When a voltage modulation signal is used as the modulation signal, a change in emission current is large with respect to a slight change in voltage, and it is desirable to use a gamma correction circuit when controlling (modulating) the signal.

FIG. 15A shows typical light emission characteristics of a phosphor serving as a light emitting portion of an image display device. As shown in the figure, the characteristics of the phosphor depend on the color of the emitted light.
The characteristic curves are not the same and have nonlinearity. The light emission characteristics of the phosphor are defined depending on the total amount of electric charge that has reached the phosphor surface of a certain unit area per unit time. That is, the nonlinearity is essential for the phosphor. Of course, the degree of nonlinearity differs depending on the type of the phosphor.

By the way, the nonlinear characteristics of the phosphor can be made substantially linear by introducing gamma correction circuits 313 and 315 for each color, which are conventionally used in CRTs and the like. However, the inclination is different for each color (see FIG. 15B). The gamma correction circuit is a circuit which changes the characteristics of a signal to be applied to a certain circuit having the above-described non-linear characteristic (tentatively referred to as characteristic A), and the characteristic inverted in advance from the characteristic A as an input signal. Is a circuit that converts the That is, by using the inverted signal as an input signal, for example, a signal that has passed through a circuit having the characteristic A is output as a signal having linearity.

As can be understood from the above description, the gamma correction circuit can be applied to any circuit having nonlinearity. Of course, it is needless to say that the present invention can be applied not only to the phosphor characteristics but also to the correction of the nonlinearity of the applied voltage-emission current characteristics of the surface conduction electron-emitting device to which the present invention is applied. In FIG. 13, the gamma correction circuit is used for correcting the characteristics of the surface conduction electron-emitting device (the gamma correction circuit 31).
3) and two circuits for phosphor characteristic correction (gamma correction circuit 315), but are not limited to this.
Needless to say, it may be constituted by one circuit. In this example, the gamma correction circuit 313 for the surface conduction electron-emitting device is not necessarily required in order to make the function easily understandable in the block diagram, and in the second configuration of the present example described later, I wrote it separately.

As described above, the first configuration of this embodiment controls the coefficient of the matrix in the matrix circuit 314 to convert the intensity of the signal corresponding to each color, thereby obtaining the characteristic of the phosphor in each color. This is to correct the difference in light emission luminance of each color (that is, the RGB balance) when the irradiation current is changed due to the difference in inclination.

Referring to FIGS. 16 and 17, a matrix circuit for realizing the first configuration in the present embodiment will be described.

FIG. 16 shows a basic type of a matrix circuit used in a general television receiver. A basic component of the matrix circuit is a resistor, and the accuracy of the resistor affects color reproducibility. Further, by changing the resistance value of this resistor, it becomes possible to change the coefficient of the matrix circuit. As described above, this embodiment is characterized in that the resistance value of the matrix circuit is controlled in consideration of the electric characteristics of the surface conduction electron-emitting device and the light emission characteristics of the phosphor.

In this embodiment, it is assumed that the surface conduction electron-emitting devices have the same electrical characteristics.

As shown in FIG. 17, R, R
Variable resistors having different resistance value variable ranges for G and B, respectively, are connected. Next, a relative ratio of inclination is calculated from the phosphor characteristics of FIG. In the case of the present embodiment, R: G: B
= 2: 1.5: 1.2. Next, the calculated relative ratio and the relative ratio of the maximum resistance variable range of the RGB variable resistors connected to the matrix circuit are set to be the same. In this embodiment, R1: R2: R3 = 2: 1.5: 1.2. The control signal for each variable resistor is a so-called “brightness adjustment knob”
Signal may be linked.

As described above, in the first embodiment,
A voltage modulation signal is used as a modulation signal. Therefore, the color tone can be adjusted with a simple circuit configuration. However, the variable resistor must be controlled precisely based on the non-linearity of the electrical characteristics of the surface conduction electron-emitting device as described above.

[Embodiment 2] Next, a second configuration will be described. In the second configuration, since a pulse width modulation signal is used, the voltage value applied to the surface conduction electron-emitting device may be determined at a point having a voltage-emission current characteristic as an operating point. Easier (for example,
(For example, non-linear correction of the surface conduction electron-emitting device is not required).

First, in FIG. 13, a block 316 surrounded by an alternate long and short dash line is a pulse width modulation circuit, which receives a voltage-modulated color signal (R, G, B) from a gamma correction circuit 315 and performs pulse width modulation. Color signals (R ′, G ′,
B ′). A sampling circuit 321 samples each of the RGB color signals at a predetermined sampling frequency. Reference numerals 322a to 322c denote multipliers which add an oscillator 323 to each sampled signal.
Signals of predetermined waveforms generated in a to 323c are superimposed. Reference numerals 323a to 323c denote transmitters, which generate signals having a predetermined waveform. Voltage comparators 324a to 324c perform pulse width modulation by comparing the signals output from the multipliers 322a to 322c with predetermined levels and outputting the results. Further, the control circuit 317
Is a circuit for controlling a display operation of the panel 320, outputs a pulse width modulation signal output from the modulation circuit 316 to the data driver 318, and outputs a scan clock to the scan driver 319 in synchronization with the pulse width modulation signal. .

The pulse width modulation circuit 316 converts the voltage modulation signal into a pulse width modulation signal. The feature of the second embodiment is that individual processing is performed for each component of the color signal.
In addition, the control coefficient is determined depending only on the emission characteristics of the phosphor (FIG. 15A).
In the second embodiment having the second configuration, the gamma correction circuit 313 for the surface conduction electron-emitting device is not always necessary.

As a specific configuration method of the pulse width modulation circuit 316 using an analog circuit, there are, for example, the following three methods.

As a first method, a constant waveform (sine wave,
In the step of superimposing a triangular wave, a sawtooth wave, etc.), there is a method of controlling the width of the obtained pulse width modulation signal by controlling the peak value of the constant waveform for each signal.

As a second method, a signal obtained by superimposing a certain waveform (sine wave, triangular wave, sawtooth wave, etc.) on a voltage signal sampled for each color is passed through a voltage comparator to thereby perform pulse width modulation. In the signal step, there is a method of controlling the pulse width modulation width by starting the comparison level voltage of the voltage comparator for each color signal.

As the third method, a combined method of the first and second methods can be considered.

However, the sampling circuit in the above method is not always necessary.

Next, a method for controlling a color signal having a gradation in a color image display device using a surface conduction electron-emitting device will be described in detail with reference to examples.

First, the pulse width modulation circuit 316 will be described with reference to FIG. FIG. 18 is a block diagram of the pulse width modulation circuit 316 in the present embodiment. FIG. 19 shows each point (A, A) of the pulse width modulation circuit 316 shown in FIG.
B1 to B3, C1 to C3).

First, the sampling circuits 321a to 321
At c, the voltage modulation signal is sampled for each color. The output at this time is shown in FIG. In this example, the same voltage modulation signal is input for both RGB. Next, the sawtooth waves are individually provided for each color from the transmitters 323a to 323c that generate the sawtooth waves to be applied to the multipliers 322a to 322c. By controlling the peak value of the waveform (in this embodiment, the sawtooth wave) for each color, the pulse width modulation of each voltage modulation signal is controlled for each color. That is, each multiplier 322a-
When the sawtooth wave is superimposed by 322c, (B1) in FIG.
A unique waveform is obtained for each color as shown in (B3). Further, by displaying these waveforms in the voltage comparator 324, pulse-modulated waveforms as shown in (C1) to (C3) of FIG. 19 are obtained.

Therefore, by determining the relative ratio of the peak values of the superimposed waveforms in consideration of the characteristics of the surface conduction electron-emitting device and the emission characteristics of the phosphor, the difference in the slope of the emission characteristics of the phosphor is determined. The correction of the difference in the light emission luminance of each color (that is, the deviation of the RGB balance) when the irradiation current is changed is generated. In this embodiment, as in the first embodiment, the electrical characteristics of the surface conduction electron-emitting device are uniform for each color, and the emission characteristics of the phosphor are the same as in FIG. Therefore, the relative ratio of the peak values of the superimposed waveform was set to 2: 1.5: 1.2, which is the relative ratio of the slope of the phosphor emission characteristics. If there are variations in the electrical characteristics of the electron-emitting devices, the numerical values may be changed accordingly. In this way, a pulse width modulated signal in which the difference in the phosphor characteristics between the colors is corrected is obtained.

Third Embodiment Next, another example of the pulse width modulation circuit 316 will be described with reference to FIGS.
FIG. 20 is a block diagram of a pulse width modulation circuit for converting a voltage modulation signal into a pulse width modulation signal according to the third embodiment.
FIG. 21 shows signal waveforms at respective points (A, B, C1 to C3) of the pulse modulation circuit shown in FIG. In this example, the comparison level voltage of the voltage comparator is controlled for each color. Also in this embodiment, the electric characteristics of the surface conduction electron-emitting device are uniform for each color, and the light emission characteristics of the phosphor are the same as in FIG.

First, the voltage modulation signal corresponding to each color is sampled for each color by the sampling circuits 321a to 321c. At this time, each sampling circuit 321a-
The output waveform of the 321c is shown in FIG. Next, the multipliers 322a to 322c are connected to the sampling circuit 321a.
A predetermined waveform (a triangular wave in this example) generated by the transmitter 323 is superimposed on the signal output from 〜321c. FIG. 21B shows the waveforms of the signals output from the multipliers 322a to 322c.

Finally, the superimposed signal is converted into a pulse width modulation signal by the voltage comparison circuits 324a to 324C individually configured for each color. Voltage comparison / comparison circuits 324a-3
By controlling the comparison level 24c, a pulse width modulated signal in which the difference in the phosphor characteristics between the colors has been corrected can be obtained. Here, the relative ratio of the comparison level voltage of the voltage comparison circuit is the relative ratio of the slope of the phosphor emission characteristics, 2: 1.5:
1.2. Here, as in the case of the second embodiment, if there are variations in the electrical characteristics of the electron-emitting devices, the numerical values may be changed accordingly. The superimposed waveforms at this time are shown in (C1) to (C3) of FIG.

As described above, Embodiments 2 and 3
According to the method, since the gradation is expressed by pulse width modulation, it is sufficient to apply a constant voltage to the surface conduction electron-emitting device, and it is not necessary to correct the nonlinear characteristics of the device. For this reason, color tone control and correction become easy. Furthermore, since the inclination of the emission characteristics of each color phosphor is corrected at the time of pulse modulation, the configurations of the matrix circuit and the gamma correction circuit are simplified.

[Embodiment 4] FIG. 22 is a block diagram of a circuit for realizing control of a color signal having a gradation according to Embodiment 4. In this embodiment, it is assumed that a signal input to the gamma correction circuit 425 as a video signal is a digital signal, which is suitable for handling a digital signal from a computer or the like. The circuit of the present embodiment is used as it is for the NTS of a television.
When applied to the C signal, once the signal is
It needs to be converted into a digital signal by the / D converter 433. In FIG. 22, reference numeral 421 denotes a demodulation unit which detects and amplifies a carrier having a certain frequency modulated by a video signal and a color signal. A video interface 422 outputs digital RGB signals from a computer or the like. 4
25 is a gamma correction circuit which corrects the gamma characteristic of the phosphor. Since the present embodiment deals with digital signals, the correction table L.L. U. T. (Look Up Table). An example is shown in FIG. Here, for simplification, the digital signal is set to 8 bits. For example, at the level of gradation 1 of low luminance, 00H (“H” is 16
The output is 00
H, at the gray level 200 of the halftone level, 5
For 5H, the output is AAH, and at the level of the high-luminance gradation 256, FFH is output for FFH as input. Then, the result of the conversion will be described.
As shown in FIG. 23C, the gamma characteristic of the phosphor shown in FIG. 23B is regarded as a linear characteristic, so that driving display can be performed. 424 is a matrix circuit and NTSC
The Y signal, I signal, and Q signal, which are three components of the signal, are converted into three components of a color signal, for example, an R signal, a G signal, and a B signal (actually, a color difference signal, for example, Y-B). This circuit is unnecessary when handling digital RGB signals of a computer or the like, but is necessary when handling video signals of a television. Also, as shown in the figure, the matrix circuit is generally formed of a resistor circuit, and is not suitable for handling digital signals. Therefore, when a television video signal is handled in this embodiment, it is desirable that the matrix circuit be handled as an analog signal and then A / D converted.

A pulse width modulation circuit 426 converts a digital RGB signal output from the gamma correction circuit 425 into a pulse width modulated luminance signal.

FIG. 24 shows a specific configuration example of the pulse width modulation circuit 426 using a digital circuit. In FIG. 24, 501
Is a latch circuit, 502 is a counter circuit, and 503 is a D-type flip-flop circuit. 8-bit digital signal D
0 to D7 are input, and the input data is
2 and set the output level high. Next, a down-counter operation is performed, and when the counter value becomes zero, the output level is made low, whereby an output signal YOE pulse-modulated according to the input data can be obtained. By forming this circuit for each of RGB, a pulse width modulation signal can be obtained for each color. Further, for example, independently for each of the RGB signals, and
32a, 432b, and 432c, the external circuits 431a to 431c (V.V.
C. O. (Using a Voltage Controlled Oscillator) as an external circuit) so that the clock frequency of the digital circuit can be controlled, thereby changing the period of the pulse width modulation reference clock and changing the pulse width over the entire pulse width modulated signal. By adjusting the color tone, it is possible to control the color tone of each individual as desired.

The structure of the circuit is an example, and is not limited to this circuit.

[Embodiment 5] FIG. 25 illustrates a principle for realizing control of a color signal having a gradation by voltage modulation in the image forming apparatus of the present embodiment. In FIG. 25, (A) shows the IV of the surface conduction electron-emitting device.
FIG. 25B is a diagram showing video signal-drive voltage characteristics gamma-corrected based on the gamma characteristics of the phosphor, and FIG. 25C is a diagram showing IV characteristics of the surface conduction electron-emitting device. FIG. 25D shows a video signal-luminance characteristic when gamma correction is performed based on the video signal, and FIG. 25D shows a video signal-luminance characteristic when gamma correction is not performed based on the IV characteristic of the surface conduction electron-emitting device. FIG. In this embodiment, (1)
Biasing the drive voltage positively or negatively, or (2) changing the gain when the drive voltage is variable, or (1)
The operation straight line is controlled on the IV characteristic by the combination of (2) and (2). As shown in FIG. 25C, the video signal (3) is output from the surface conduction electron-emitting device by the I-
Since the gamma correction is performed based on the V characteristic, the luminance changes linearly linearly with the video signal.

FIG. 26 is a block diagram of the actual circuit configuration. Y, I, Q detected and amplified in the same manner as in Embodiment 1.
The signals are converted into R, G, and B signals by a matrix circuit, and the gamma correction circuit 501 performs gamma correction based on the gamma characteristics of the phosphor. Next, gamma correction is performed by the gamma correction circuit 602 based on the characteristics of the surface conduction electron-emitting device for each of the RGB signals.

Here, as described in the principle explanation, the luminance can be adjusted by voltage modulation by controlling the bias voltage or the gain in conjunction with the input video signal for each color.

Further, R and R are independent of the input signal for each color.
By controlling the bias voltage or the gain using the G / B bias adjuster or the R, G, B gain adjuster, it is also possible to adjust the color according to personal preference.

In this embodiment, the case where the video signal is treated as an analog signal is described, but a circuit configuration for a digital signal is of course also possible.

As described above, according to the first to fifth embodiments, in the color image display device using the surface conduction electron-emitting device, the gradation control and the control of the color signal, that is, the color signal having the gradation It is possible to easily realize the control of color shift, color balance, and the like, which is a problem in realizing the above, on the image receiving device side.

Further, since the color tone control methods of the second and fourth embodiments are controlled independently of the electron-emitting devices, when the electric characteristics of the surface conduction electron-emitting devices corresponding to each color vary. It is also possible to correct it. Therefore, the production yield of the color image forming apparatus is improved.

[Embodiment 6] Next, an embodiment using a display panel having a surface conduction electron-emitting device as an electron source and having a configuration different from that of FIG. 11 will be described.

Before describing this embodiment in detail, the display device of this embodiment will be briefly described. This display device
An electron source substrate in which a plurality of surface conduction electron-emitting devices are two-dimensionally arranged in a vacuum container; and a phosphor that emits visible light by irradiating an electron beam at a position facing the electron source substrate. Is maintained at a degree of vacuum higher than 1 × 10 ⁻⁴ [Torr]. Further, the surface conduction electron-emitting devices arranged two-dimensionally on the electron source substrate have driving wires connected to both ends of the device so that they can be selected and driven line by line. A voltage is uniformly applied to both ends of the surface conduction type electronic device on the scan line to be scanned, and the device is driven.

Further, a grid long in a direction perpendicular to the line direction for individually controlling the amount of emission current reaching the phosphor is arranged between the surface conduction electron-emitting device and the phosphor. In addition, by controlling the voltage applied to the grid in accordance with the image signal, the light emission luminance on the phosphor screen is controlled.

Further, according to the first color balance correction method according to the present embodiment, the red (R), green (G), and blue (B) signals which are voltage-modulated according to the luminance for color display. Correcting according to the emission characteristics of each of the R, G, and B phosphors and / or correcting according to the voltage dependency of the grid, and voltage modulating the grid with an appropriate color balance. Color display.

Further, according to the second color balance correction method of the present embodiment, correction is made in accordance with the emission characteristics of each of the R, G, and B phosphors, and pulse width modulation is performed in accordance with the luminance for color display. The color display is performed by applying the R, G, and B signals to the grid.

Here, the grid is an electrode for controlling the trajectory of the electron beam emitted from the electron-emitting device, and the amount of the electron beam illuminating the phosphor screen is controlled by an electric signal applied to the electrode. it can. Note that this electrode may also serve as an electrode for converging and deflecting the electron beam. In this embodiment, the grid is disposed between the electron-emitting device and the phosphor screen. However, for example, the electron-emitting device and the grid may be provided on the same surface. A configuration in which an electron-emitting device is arranged between the surface and the surface is also possible. As described above, a pulse voltage is used as an electric signal to be applied to the grid,
In addition to controlling the amount of electron beam that irradiates the phosphor screen by changing the pulse peak value or pulse width, it is not limited to those that change only one of the pulse peak value or pulse width alone Absent. For example, both the peak value and the pulse width may be changed,
Alternatively, the number of pulses may be changed using a plurality of pulses to control the amount of electron beams irradiating the phosphor screen.

Hereinafter, this embodiment will be described in detail.

FIG. 27 is a block diagram of a circuit according to the first embodiment for realizing control of a color signal having a gradation in the present embodiment.

In FIG. 27, input video signal 7
Reference numeral 10 denotes a signal obtained by modulating a carrier wave of a certain frequency with a video signal and a color signal, and is input to the filter circuit 711. The filter circuit 711 receives the input video signal 710
Is a circuit for detecting and amplifying the same, and can be obtained by diverting a circuit similar to a conventional television circuit. The matrix circuit 712 is an important circuit in a conventional television circuit, and the circuit constant of the matrix circuit 712 is N
The Y signal, I signal, and Q signal, which are the three components of the TSC signal, are
The three components of the color signal are converted into an R signal, a G signal, and a B signal. As coefficients of the matrix circuit 712, FIG.
Are generally used. In general, the coefficient is determined by the coefficient of a matrix circuit when an image is converted into an NTSC signal using a television camera.
However, this coefficient is not uniquely determined and can be changed by various characteristics on the image receiving side.

By the way, in the case of a signal by a method other than the NTSC, the configuration of the filter circuit 711 and the configuration of the matrix circuit 712 are naturally different from each other. For example, as an input signal, a component of a certain color signal (for example, an analog RGB signal 721 shown in FIG.
When the signal 722) is input, the analog RGB signal 721 is directly input to the correction circuit (1) 713 at the subsequent stage, and the digital RGB signal 722 is converted into an analog signal by the D / A converter 716, and then corrected. The signal is input to the circuit (1) 713. The input image signal may be a data signal from a computer, a baseband signal from a television camera, or the like.

Next, the correction characteristics of the correction circuit (1) 713 and the correction circuit (2) 714 will be described.

FIG. 28 is a diagram for explaining the light emission characteristics of the phosphor of the present embodiment. FIG. 28A shows typical light emission characteristics of a phosphor which is a light emitting portion of a color image display device. I have. As shown in the figure, the characteristic curve of the phosphor is not exactly the same and has non-linearity due to the difference in the color of emitted light. Regarding this nonlinearity, the conventional CRT
By introducing the gamma correction circuit used in the above-mentioned method, the characteristics can be made substantially linear. However,
Since the inclination is different for each color (FIG. 28B), the correction circuit (1) 713 in FIG. 27 is provided to correct the inclination according to each of the R, G, and B color components. In the following description, it is assumed that gamma correction has been performed on the phosphor characteristics.

Further, as will be described later, the grid, which is a means for controlling the irradiation current, also has a non-linearity as shown in FIG. 5 with respect to the applied voltage, so that the correction circuit (2) 714 in FIG. Corrected to image signal. By performing voltage modulation on the voltage applied to the grid in this manner, an image having linear characteristics can be displayed. Instead of this voltage modulation, a pulse width modulation as described later may be performed to control the voltage applied to the grid.

Further, the R, G, B signals are supplied to the control circuit 715.
Accordingly, by rearranging and synchronizing the data on a pixel-by-pixel basis and outputting the rearranged data to the data driver 718, an image display for one line can be performed. In parallel with this, a horizontal synchronization signal 723 extracted from the video signal 710 is input, and a line synchronization signal is output to the scanning driver 719 through the control circuit 717. This makes it possible to sequentially scan the display lines and display a two-dimensional image on the display panel 720.

The color image display device of the present embodiment described above brings about an excellent effect in a grid type color image display device using surface conduction electron-emitting devices.

The basic structure, manufacturing method and characteristics of the surface conduction electron-emitting device constituting the display panel 720 of this embodiment are as described above.

FIG. 29 shows a typical configuration example of the color image display device of this embodiment.

FIG. 29 shows a substrate 801 in which a large number of the electron-emitting devices are arranged in parallel, and a large number of rows in which both ends of each device are connected by wiring are arranged (for example, Japanese Patent Application Laid-Open No. After fixing on the rear plate 802, a grid 806 having electron passing holes 805 was arranged above the substrate 801 in a direction orthogonal to the device electrodes 803 of the electron-emitting device. Further, a face plate 810 is placed approximately 5 mm above the substrate 801.
(A structure in which a fluorescent film 808 and a metal back 809 are formed on an inner surface of a glass substrate 807) is provided via a support frame 811. And this face plate 8
10, frit glass was applied to the joint between the support frame 811 and the rear plate 802, and was baked at about 400 ° C. to 500 ° C. for 10 minutes or more in the air or in a nitrogen atmosphere for sealing. Also, the substrate 80 is placed on the rear plate 802.
1 was also fixed with frit glass.

In FIG. 29, reference numeral 804 denotes an electron emitting portion. In this embodiment, as described above, the face plate 81 is provided.
0, the support frame 811, and the envelope 812 with the rear plate 802.
However, since the rear plate 802 is provided mainly for the purpose of reinforcing the strength of the substrate 801, if the substrate 801 itself has sufficient strength, the separate rear plate 802 is unnecessary, and the rear plate 802 is directly attached to the substrate 801. Sealing the support frame 811;
The envelope 812 may be constituted by the face plate 810, the support frame 811, and the substrate 801.

The fluorescent film 808 of the face plate 810
Is composed of a phosphor in the case of a monochrome display, but is composed of a black conductor 291 called a black stripe or a black matrix and a phosphor 292 depending on the arrangement of the phosphor in the case of a phosphor film for color display. You. The purpose of providing such a black stripe and black matrix is to make the three-color phosphor required for color display black between the respective phosphors 292 so that the color mixture and the like become inconspicuous. The purpose is to suppress a decrease in contrast due to reflection of external light on the film 808. In this embodiment, the phosphor 292 has a stripe shape (FIG. 1).
2 (A)). In this method, a black stripe was first formed, and a phosphor of each color was applied to a gap between the black stripes to form a phosphor film 808.

In this embodiment, a material mainly composed of graphite is used as a material for forming a black stripe. However, any material having conductivity and low light transmission and reflection can be used. However, it is not limited to this. As a method of applying the phosphor 292 to the glass substrate 807, a precipitation method or a printing method is used in the case of monochrome, but a slurry method is used in the present embodiment which is a color display. However, it is a matter of course that the same coating film can be obtained even in the case of the color display by using the printing method.

Further, a metal back 809 is usually provided on the inner surface side of the fluorescent film 808. This metal back 809
The purpose of this is to increase the brightness by reflecting the light toward the inner surface side of the light emitted from the phosphor 292 toward the face plate 810 side, to increase the brightness, to act as an electrode for applying an electron beam accelerating voltage, Phosphor 29 from damage caused by the collision of negative ions generated in vessel 812
2 and the like. The metal back 809 is formed by forming the fluorescent film 808 and then forming the fluorescent film 808.
Was manufactured by performing a smoothing treatment (usually called filming) on the inner surface of the substrate, and thereafter, vacuum-depositing aluminum (Al). The face plate 810 may be provided with a transparent electrode (not shown) on the outer surface side of the fluorescent film 808 in order to further increase the conductivity of the fluorescent film 808, but in this embodiment, only the metal back 809 is sufficient. Omitted because conductivity was obtained. Further, when sealing the joint between the face plate 810, the support frame 811, and the rear plate 802, the phosphor 2 of each color is used in the case of color display.
Since the electron-emitting device 92 must correspond to the electron-emitting device 92, sufficient alignment was performed.

The atmosphere in the glass container completed as described above is evacuated by a vacuum pump through an exhaust pipe (not shown), and after reaching a sufficient degree of vacuum, the external terminals Dr1 to D4 are set.
The above-described forming is performed by applying a voltage between the element electrodes 803 through rm and DL1 to DLm. Thus, the electron-emitting portion 804 was formed, and the above-described electron-emitting device was formed on the substrate 801. Finally, the exhaust pipe (not shown) was welded by heating with a gas burner at a degree of vacuum of about 10 ⁻⁶ Torr, and the envelope 812 was sealed. Finally, a getter process was performed to maintain the degree of vacuum after sealing. In this method, a getter disposed at a predetermined position (not shown) in an image display device is heated by a heating method such as resistance heating or high-frequency heating immediately before or after sealing to form a deposited film. Processing. The getter is usually composed mainly of Ba or the like, and the degree of vacuum is maintained by the adsorption action of the deposited film.

In the image display device formed as described above, each of the electron-emitting devices has a terminal Dr1 outside the container.
By applying a voltage through .about.Drm and DL1 to DLm, electrons are emitted from each electron emitting portion 804. FIG. The electrons emitted in this way pass through the electron passage hole 805 of the modulation electrode 806 and then pass through the high voltage terminal Hv to the metal back 809.
Alternatively, the phosphor is accelerated by a high voltage of several kV or more applied to a transparent electrode (not shown) and collides with the phosphor film 808, whereby the phosphor 292 is excited and emits light. At that time, the modulation electrode 80
The voltage corresponding to the information signal is applied to the external terminals G1 to Gn.
Is applied to control the electron beam passing through the electron passage hole 805 to display an image.

In this embodiment, about 5 μm above the substrate 801 by about 10 μm via SiO ₂ (not shown) which is an insulating layer.
Modulation electrode 80 having 0 micron diameter electron passage hole 805
By arranging 6, when the acceleration voltage was applied at 6 kV, the on / off of the electron beam could be controlled by the modulation voltage within 50 V.

FIG. 30 is a diagram showing the relationship between the grid voltage VG applied to the modulation electrode 806 and the phosphor screen current flowing to the phosphor film 808. Here, when the grid voltage VG is increased, the phosphor screen current starts to flow at a certain threshold voltage VG1 or more, and as the grid voltage VG is further increased, the phosphor screen current monotonously increases as shown in FIG. And eventually saturates.

The configuration described above is a schematic configuration necessary for producing an image display device.
The detailed part is not limited to the above description, and can be appropriately selected so as to be suitable for the use of the image display device.

As a method of obtaining color balance, it can be performed by changing the coefficients (see FIG. 14) of the conversion formula in the matrix circuit 712 of FIG. The operation is the same as described above. The control circuit 71
5 includes an R adjuster, a G adjuster, and a B adjuster shown in FIG. 26, and can perform the same operation.

[Embodiment 7] Next, a seventh embodiment of the present invention will be described with reference to FIG. In FIG. 31, portions common to FIG. 27 are denoted by the same reference numerals, and description thereof will be omitted.

In FIG. 31, an analog RGB signal 921 obtained in the same manner as in FIG.
Is converted into a digital RGB signal. When the digital RGB signal 922 is input, the conversion by the A / D converter 925 becomes unnecessary.

Further, the RGB signals converted into digital signals
Signal or input digital RGB signal (rgb)
Is converted to a pulse length in accordance with the luminance. This pulse width modulation circuit 926
Is a correction data table 9 created based on the difference in the coloring characteristics of the respective phosphors 292 corresponding to the three primary colors.
27 independently weights each of the R, G, and B signals, and converts the R, G, and B signals into RGB signals (r ', g', b ') with pulse width modulation. The RGB signals (r ′, g ′, b ′) are input to the control circuit 915. Further, a signal corresponding to the image data is output to the data driver 918 by the same operation as in FIG. 27, and an image for one line is displayed. In synchronization with this display operation,
The two-dimensional image can be displayed on the display panel 920 by driving the scanning driver 919 by the control circuit 917 in the same operation as in FIG. Needless to say, the above operation can also be realized by the circuits shown in FIGS.

FIG. 32 is a circuit diagram of the circuit shown in FIG.
An analog RGB signal is sampled by a sampling circuit 1028, and the sampled analog RGB signal is sampled.
The pulse width modulation circuit 1026 performs pulse width modulation on the B signal. This pulse width modulation circuit 1026
a also refers to the correction data table 1027a,
Each of the modulated R, G, and B signals is independently weighted. The signal thus modulated is supplied to the control circuit 10
15 and becomes a drive signal of the data side driver 1018.

The pulse width modulation circuit 1026 shown in FIG.
The circuit configuration a can be performed by the same circuit and operation as those in FIGS. 18 to 21 described above.

As described above, according to this embodiment, in a color image display device using a surface conduction electron-emitting device, gradation control and color signal control can be performed. That is, it is possible to easily realize the control of color shift, color balance, and the like, which are problematic when displaying a color signal having a gradation, on the image receiving device side.

Further, since the color tone control method of this embodiment is performed independently of the electron-emitting device, even if the electric characteristics of the surface conduction electron-emitting device corresponding to each color vary, it is corrected. It is possible to improve the production yield of the color image display device.

The application of the display device according to the present invention is based on NT.
The present invention can be widely used for a device that performs television display based on an SC system television signal, and a display device that is directly or indirectly connected to a television signal or various image signal sources such as a calculator, an image memory, and a communication network. In particular, it is suitable for displaying a large screen that displays a large-capacity image.

[0240]

As described above, according to the present invention, there is an effect that a flat type color display excellent in gradation display can be performed.

[Brief description of the drawings]

FIGS. 1A and 1B are a plan view and a cross-sectional view of a preferred planar type surface conduction electron-emitting device used in an embodiment.

FIG. 2 is a view showing a manufacturing process of a suitable surface conduction electron-emitting device used in the present invention.

FIG. 3 is a diagram showing a forming voltage waveform of a surface conduction electron-emitting device used in an example.

FIG. 4 is a diagram showing an apparatus for evaluating characteristics of a surface conduction electron-emitting device used in an example.

FIG. 5 is a view showing electrical characteristics of a preferred surface conduction electron-emitting device used in an example.

FIG. 6 is a view showing an element structure of a vertical surface conduction electron-emitting device suitable for use in an example.

FIG. 7 is a plan view illustrating a configuration of a multi-electron beam source used in the display device according to the first embodiment of the present invention.

8 is a cross-sectional view for explaining a manufacturing process of the multi-electron beam source of FIG.

9 is a cross-sectional view for explaining a manufacturing process of the multi-electron beam source of FIG.

FIG. 10 is a plan view for explaining a method for manufacturing the multi-electron beam source of FIG.

FIG. 11 is a perspective view illustrating a configuration of a display panel used in the display device of the example.

FIG. 12 is a partial plan view of a face plate of a display panel used in the display device of the example.

FIG. 13 is a circuit block diagram for realizing gamma correction or color balance adjustment in the display device according to the embodiment of the present invention.

FIG. 14 is a diagram illustrating an example of general matrix coefficients of a matrix circuit.

FIG. 15 is a view showing emission characteristics of a phosphor.

FIG. 16 is a diagram illustrating a basic form of a matrix circuit used in a general television.

FIG. 17 is a diagram illustrating a configuration of a matrix circuit in an example.

FIG. 18 is a block diagram illustrating a configuration example of a pulse width modulation circuit according to the second embodiment.

19 is a diagram showing signal waveforms at respective points of the circuit shown in FIG.

FIG. 20 is a block diagram illustrating a configuration of a pulse width modulator according to a third embodiment.

21 is a diagram showing signal waveforms at respective points of the circuit shown in FIG.

FIG. 22 is a block diagram of a circuit for controlling a color signal having a gradation according to the fourth embodiment.

FIG. 23 is a diagram for explaining a method of correcting the gamma characteristic of the phosphor by the circuit of FIG. 22;

FIG. 24 is a circuit diagram showing an example of a pulse width modulation circuit used in FIG.

FIG. 25 is a diagram for explaining a control method of a color signal having a gradation in the fifth embodiment.

FIG. 26 is a block diagram of a circuit for controlling a color signal having a gray scale according to the fifth embodiment.

FIG. 27 is a block diagram illustrating a configuration of a color image display device according to a sixth embodiment.

FIG. 28 is a diagram showing emission characteristics of a phosphor.

FIG. 29 is a perspective view illustrating a configuration of a color display panel used in the display device of Example 6.

30 is a diagram showing modulation characteristics of grid electrodes of the display panel of FIG. 29.

FIG. 31 is a block diagram of a circuit for controlling a color signal having a gray scale according to a seventh embodiment.

FIG. 32 is a block diagram of a circuit for controlling a color signal having a gray scale according to an eighth embodiment.

FIG. 33 is a plan view of a conventional surface conduction electron-emitting device.

FIG. 34 is a diagram illustrating an example of a basic configuration of a conventional display device.

FIG. 35 is a sectional view of the conventional display device of FIG. 2;

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G09G 3/20 G09G 3/20 641Q 642 642L H01J 1/316 H01J 31/12 C 31/12 H04N 5/68 B H04N 5/68 H01J 1/30 E (72) Inventor Asadake Suzuki 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside the Canon Inc. (72) Inventor Yasuyuki Yokoro Yoko 3-30 Shimomaruko, Ota-ku, Tokyo No. 2 Inside Canon Inc. (72) Inventor Hidetoshi Suzumi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Toshihiko Takeda 3-30-2 Shimomaruko 3-chome, Ota-ku, Tokyo Inside Non Corporation (72) Inventor Seiji Isono 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Corporation (72) Inventor Yoshiyuki Nagata Tokyo Univ. 3-30-2 Shimomaruko, Ta-ku F-term (reference) in Canon Inc.

Claims (21)

[Claims] At least an electron beam source in which a plurality of surface conduction electron-emitting devices are arranged on a substrate, phosphors of three primary colors of red, green and blue which emit light by irradiation of an electron beam, and an image signal A modulating means for modulating an electron beam irradiating the phosphor on the basis of the phosphor, wherein the modulating means reduces a nonlinearity of the luminance of the phosphor with respect to an irradiation current value to the phosphor. An image forming apparatus, comprising: a correction unit for correcting, and modulating an electron beam based on an image signal corrected in advance by the correction unit. 2. The electron beam generating source according to claim 1, wherein a plurality of surface conduction electron-emitting devices are two-dimensionally arranged on a substrate, and the devices are connected in a matrix by row-direction wiring and column-direction wiring. The image forming apparatus according to claim 1, wherein the image forming apparatus is a source. 3. The apparatus according to claim 2, wherein said modulating means includes a correcting means for correcting an image signal based on at least a gamma characteristic between an emission current intensity of surface conduction emission and an applied voltage. Image forming apparatus. 4. The apparatus according to claim 2, wherein said modulating means includes a correcting means for correcting an image signal based on at least a gamma characteristic of a light emission intensity of the phosphor and an irradiation electron beam amount. Image forming device. 5. An electron beam generating source comprising: an element group in which a plurality of surface conduction electron-emitting devices are arranged on a substrate along a row direction; and a column direction substantially orthogonal to the row direction on or outside the substrate. 2. The image forming apparatus according to claim 1, wherein the image forming apparatus is an electron beam generating source including an electrode array in which grid electrodes are arranged along. 6. The apparatus according to claim 5, wherein said modulating means comprises a correcting means for correcting an image signal based on at least a gamma characteristic between a light emission intensity of a phosphor and an amount of an irradiated electron beam. Image forming apparatus. 7. The modulator according to claim 5, wherein said modulating means includes a correcting means for correcting an image signal based on at least a gamma characteristic of a transmitted electron beam amount of a grid electrode and a grid electrode applied signal. The image forming apparatus as described in the above. 8. The image forming apparatus according to claim 1, wherein the modulating unit modulates a length of time for irradiating the phosphor with an electron beam based on the gamma-corrected image signal. 9. The image forming apparatus according to claim 8, wherein the modulation unit includes a component adjustment unit that independently adjusts a modulation signal for modulating an electron beam for each color component. 10. The component adjusting means has a comparator for each color component of the gamma-corrected image signal, and independently adjusts the relative relationship between the comparison reference of each comparator and the image signal. The image forming apparatus according to claim 9, wherein: 11. The component adjustment means includes an amplifier and a comparator capable of independently adjusting an amplification factor for each color component of a gamma-corrected image signal, and outputs the image signal amplified by the amplifier to the comparator. The image forming apparatus according to claim 9, wherein a modulation pulse is generated by comparing with a predetermined reference value. 12. The apparatus according to claim 1, wherein the component adjusting means has a pulse width modulator for each color component of the gamma-corrected image signal, and independently adjusts a frequency of an operation reference clock of each pulse width modulator. The image forming apparatus according to claim 9, wherein 13. The image forming apparatus according to claim 1, wherein the modulation unit modulates a current amplitude of an electron beam applied to the phosphor based on the gamma-corrected image signal. 14. The image forming apparatus according to claim 13, wherein said modulating means includes means for independently adjusting a modulation signal for modulating an electron beam for each color component. 15. The apparatus according to claim 14, wherein said component adjusting means has a level shifter for each color component of the gamma-corrected image signal, and independently adjusts a shift amount of each level shifter. The image forming apparatus as described in the above. 16. The apparatus according to claim 14, wherein said component adjusting means has an amplifier for each color component of the gamma-corrected image signal, and independently adjusts and amplifies an amplification factor of each amplifier. Image forming apparatus. 17. An electron beam source in which a plurality of surface conduction electron-emitting devices are arranged on a substrate, phosphors of three primary colors of red, green and blue emitted by irradiation of an electron beam, and an image signal. What is claimed is: 1. An image forming method for an image forming apparatus, comprising: at least a modulating unit for modulating an electron beam applied to a phosphor. A correction step of correcting the non-linearity of the luminance of the phosphor with respect to the irradiation current value to the phosphor of the image forming apparatus using the electron-emitting device as an electron beam generating source; A modulating step of modulating the electron beam based on the image forming method. 18. The method according to claim 18, wherein the modulating step includes a step of generating a modulation signal for modulating a length of time for irradiating the phosphor with an electron beam based on the image signal gamma-corrected in the correcting step. The image forming method according to claim 17, wherein 19. The method according to claim 19, wherein the modulating step includes a step of generating a modulation signal for modulating a current amplitude of an electron beam applied to the phosphor based on the image signal gamma-corrected by the correcting step. The image forming method according to claim 18, wherein: 20. The image forming method according to claim 17, wherein the modulating step includes a step of independently adjusting the image signal for each color component based on the image signal gamma-corrected in the correcting step. . 21. The image according to claim 18, wherein said modulating step includes a step of independently adjusting a modulating signal for each color component based on the image signal gamma-corrected by said complementing step. Forming method.