JP2002110074A - Electron beam exciting phosphor display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent an electron source from being destroyed by electrostatics and reduce factors for causing defective pixels. SOLUTION: In an electron beam exciting phosphor display comprising a rear plate 11 provided with multiple scanning line wiring 16 and multiple modulation line wiring 17, which are so arranged that the former and the latter cross each other at right angles, and electron emission elements 12 for display arranged on each intersection of the wiring 16, 17, and a face plate which is so arranged that it faces the rear plate 11 with a certain distance therebetween and is provided with a phosphor layer and an anode electrode on the side facing the rear plate 11, common wiring 15 is provided outside the display area on the rear plate 11, and electron emission elements 13, 14 for electric discharge are provided among the common wiring 15, the scanning line wiring 16 and the modulation line wiring 17.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electron-beam-excited phosphor display device using electron-field emission, and more particularly, to an electron-beam-excited phosphor display device having a function of preventing electrostatic breakdown.

[0002]

2. Description of the Related Art Conventionally, a display system in which a phosphor is excited by an electron beam has a high response speed, has a wide viewing angle characteristic, and is a light-emitting display device. It has been widely used as a device. However, as the screen size of the cathode ray tube increases, the weight and the depth increase, and the size of the cathode ray tube has been limited to 40 inches so far, and the size of 30 inches or less has been generally used for home use. On the other hand, video signals are transitioning from NTSC to Hi-Vision, and a display device with a large screen is desired with an increase in image quality.

A thin plasma display panel (PDP) has been proposed as a display device capable of providing high-quality images on a large screen.
Has been put to practical use. The PDP can form a large screen panel at low cost because wiring and pixels can be formed by a printing method, but it has low luminous efficiency, large power consumption, requires a driving IC with a high withstand voltage, and increases the cost of a driver IC. Has disadvantages.

[0004] Recently, an electron-beam-excited phosphor display device using a flat-type electron source has attracted attention as a large-screen thin display (E. Yamaguchi, et.al., “A1O-in. SCE-
emitter display ”, Journal of SID, Vol. 5, p345, 199
7). This electron-beam-excited phosphor display device is based on the fact that an electron-emitting device array as a flat-type electron source can be formed using printing technology, and that the same emission principle as a cathode ray tube is used for phosphor-excited emission by electrons. Since the type electron source can be driven at a voltage of more than ten volts, there are advantages such as the use of a driving IC having a low withstand voltage.

FIG. 10 shows a main structure of a conventional electron beam excited phosphor display device using a flat electron source. On a glass substrate 11 serving as a rear plate, planar electron sources 12 are arranged in a matrix. The electron source 12 includes the electrode 2
An electrode 2 is formed by disposing a fine particle film 23 between
It is driven by the voltage applied between 1 and 22. A phosphor film 32 for emitting R, G, B light is applied to each pixel on a glass substrate 31 called a face plate facing the rear plate 11, and an anode electrode 33 made of aluminum is coated thereon. Is formed. A vacuum is maintained between the plates 11 and 31 and the electron source 12
The electrons 108 emitted from the phosphor film 32 are accelerated by the anode voltage and irradiated on the phosphor film 32. Then, the phosphor film 32 is excited to emit light by the energy of the accelerated electrons.

The principle of light emission itself is the same as that of a cathode-ray tube, but a cathode-ray tube scans an electron beam emitted from an electron gun with a deflecting coil or the like to scan the screen, whereas a flat-type electron source is used. In the phosphor display device, the phosphor layer of each pixel is excited and emits light by electrons emitted from an electron source provided for each pixel. Also,
The distance between the rear and the face plate is about several millimeters, and there is a great difference from a cathode ray tube in a thin display device.

FIG. 11 is a plan view showing a configuration of a rear plate of the above-mentioned electron beam excited phosphor display device. On the glass substrate 11, the scanning line wiring 16 (16 ₁ , 16 ₂ , 16
_3, ~) in the horizontal direction, also the modulation line wiring 17 (17 _1, 1
7 ₂ , 17 ₃ ,...) Are formed in the vertical direction. A pixel is defined at each intersection of the scanning line wiring 16 and the modulation line wiring 17,
A planar electron source 12 serving as an electron-emitting device is provided. A position indicated by a broken line 18 in the figure is a sealing region where the rear plate and the face plate are bonded.

[0008] Upon application of sequential selection pulses to the scanning lines 16, the electron source was connected to the scanning lines 16 _{which are} selected 1
2, a desired voltage is applied according to the voltage of the modulation line voltage pulse applied simultaneously. Since the amount of electrons emitted from the electron source 12 can be controlled in accordance with the applied voltage of the modulation line voltage pulse, an image can be displayed by irradiating the required amount of electrons to the phosphor.

An electron-beam-excited phosphor display device using such a flat-type electron source uses phosphor-excited light emission by an electron beam with high luminous efficiency, and therefore consumes little power even on a large screen. In addition, the phosphor emits light only for a very short period of time when the scanning line wiring is selected.
Since the display is not a hold type display like P, a very natural image can be displayed even in the moving image display. Also, LC
Unlike D, there is no viewing angle dependency of the screen luminance, and it has a wide viewing angle characteristic. Further, since the flat-type electron source operates at more than ten volts, it can be driven by a driver IC having a low withstand voltage.
There are such features.

As the electron emitting element of the electron beam excited phosphor display device, there is a projection type electron source shown in FIG. 12 in addition to the above-mentioned flat type electron source. A conical electron emission emitter 72 is provided on an electrode 73 on the glass substrate 11, and a gate electrode 74 is provided on an interlayer insulating film 75 covering them. The gate electrode 74 and the interlayer insulating film 75 have minute holes of about 1 μm or less centered on the apex of the emitter 72.

In the configuration shown in FIG. 12, when a voltage is applied between the gate electrode and the emitter electrode, an extremely large electric field is induced at the tip of the emitter due to electric field concentration, and electrons are emitted. Generally, the voltage at which electrons are emitted depends on the sharpness (curvature radius) of the tip of the emitter and the fineness of the opening diameter of the gate electrode, but electrons can be emitted with a gate voltage of several tens of volts. Further, since the projection type emitter is formed by a thin film process, it is not suitable for a display device having a large area. However, since it is an electron beam excited phosphor display device, high image quality can be realized.

However, this kind of electron-beam-excited phosphor display device has the following problems. That is,
In an electron source array in which electron-emitting devices (electron sources) are provided in a matrix, the electron source is destroyed by the influence of static electricity generated during the manufacturing process or operation of the device after the process in which the electron source is formed, resulting in a defect. There was a problem of becoming a pixel. The processes after the electron source is formed include an electron source array inspection process, an assembly process combined with a face plate, a vacuum cell exhaust process for evacuating, an electrical inspection process after assembly, an aging process, and a drive IC. There are a mounting process for connection, an assembly process for assembling into a housing, a display inspection process, and the like. In any of these steps, there is a possibility that static electricity may be generated because the substrate is an insulator made of plus, and there is a problem of destruction of the electron source element.

[0013]

As described above, in the conventional electron beam excited phosphor display device, the electron source is affected by the static electricity generated during the manufacturing process or operation of the device after the process of forming the electron source. Was destroyed, resulting in a defective pixel.

The present invention has been made in view of the above circumstances, and has as its object to prevent electron source destruction due to static electricity, and to reduce the generation of defective pixels by electron beam-excited fluorescence. An object of the present invention is to provide a body display device.

[0015]

(Structure) In order to solve the above problem, the present invention employs the following structure.

That is, according to the present invention, there are provided a first substrate and a second substrate which are opposed to each other at a fixed interval, and a plurality of parallel substrates which are formed on the first substrate on the side opposite to the second substrate. Scanning line wiring and the first substrate on the side facing the second substrate,
A plurality of modulation line wirings parallel to each other formed in a direction intersecting with the scanning line wiring, and formed in a pixel portion defined at each intersection of the scanning line wiring and the modulation line wiring,
A display electron-emitting device in which one electrode is connected to the scanning line wiring and the other electrode is connected to the modulation line wiring; and a phosphor provided on a second substrate on the side facing the first substrate. In the electron-beam-excited phosphor display device including a layer and an anode electrode, a common line is provided outside a display region formed of the pixel unit, and the common line is connected to each of the scanning line line and the modulation line line. A discharge electron-emitting device is connected therebetween.

Here, preferred embodiments of the present invention include the following. (1) The common wires are installed in parallel, and the discharge electron-emitting devices are selectively connected to the common wires arranged in parallel.

(2) Each of the display and discharge electron-emitting devices is formed of a conductive thin film and an electron-emitting portion formed in the thin film. (3) The display electron-emitting device is a device in which a plurality of basic devices each including a projecting emitter electrode and a gate electrode having a circular opening centered on the projecting tip of the emitter electrode are arranged. The electron-emitting device for use is a device in which a plurality of elements in a basic unit including two basic elements in which the basic elements are connected in parallel in opposite directions are arranged.

(4) The number of projection-type emitter electrodes constituting the discharge electron-emitting device should be larger than the number of projection-type emitter electrodes constituting the display electron-emitting device. (5) The current driving capability of the discharge electron-emitting device must be greater than the current driving capability of the display electron-emitting device. (6) The electron emission start voltage of the discharge electron emission element is lower than the electron emission start voltage of the display electron emission element.

(7) Both the first and second substrates are glass substrates. (8) The phosphor layer is aligned with the pixel section. (9) Each of the display and discharge electron-emitting devices must be provided in an evacuated area.

(Operation) The present inventors have investigated the state of electrostatic destruction, and found that the application of static electricity is caused by the induction of static electricity from the outside of the glass substrate to the scanning line wiring or the modulation line wiring. It has been found that the electron-emitting devices (electron sources) travel through these wirings to the inside of the matrix (display region), and the electrically weak electron-emitting devices (electron sources) are destroyed by discharge. Both the planar electron source and the projection electron source operate to emit electrons in a strong electric field. The current-voltage characteristics at this time are Faw11
It shows er-Nordheim-type conduction, and the increase in current is greater than the increase in applied voltage. For this reason, if the voltage is equal to or higher than the threshold voltage at which electron emission starts, an excessive current flows due to a slight rise in voltage, and when the applied voltage is extremely high, heat is generated to destroy the electron source.

Therefore, in the present invention, a discharge electron-emitting device for discharging static electricity is provided outside the matrix,
The configuration is such that the static electricity is discharged before the static electricity is applied to the internal electron source (display electron-emitting device) through the matrix wiring, thereby protecting the display electron-emitting device from the static electricity. The discharge electron-emitting device has the same configuration as the display electron-emitting device, and is configured to discharge the static electricity as soon as possible.

When the threshold voltage of the discharge electron-emitting device is lower than that of the display electron-emitting device, the sensitivity to static electricity is increased, which is more effective. Further, by forming the discharge electron-emitting device at the same time as the display electron-emitting device, the sensitivity to static electricity can be optimized. Further, the discharge electron-emitting devices are provided outside the matrix on all the scanning line wirings and the modulation line wirings, and between the common wiring provided outside the matrix.
Further, the discharge electron-emitting device has a larger emission point area of the electron-emitting portion than the display electron-emitting device, so that a relatively large charge can flow. In this manner, in the display operation state, the discharge electron source is applied with only a voltage lower than the threshold voltage, so that the discharge can be started as soon as static electricity is applied.

With the above-described structure, it is possible to prevent destruction due to static electricity generated during the manufacturing process of the electron source, and to realize an electron-beam-excited phosphor display device with a high yield and no defective pixels. Further, the configuration for preventing electrostatic destruction according to the present invention can effectively prevent electron source destruction from static electricity not only during a process but also during use as a display device. When the protection element is finally unnecessary, only the discharge electron-emitting elements provided in the periphery can be selectively electrically opened.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below with reference to the illustrated embodiments.

(First Embodiment) FIG. 1 shows a first embodiment of the present invention.
It is a figure which shows the structure of the rear plate of the electron beam excitation phosphor display device concerning embodiment 2 in planar view.

A scanning line wiring 16 (16 ₁ , 16 ₂ , 1) is placed on a glass substrate (first substrate) 11 as an insulating substrate.
6 ₃ ,...) In the horizontal direction and the modulation line wiring 17 (17 ₁ ,
17 _2, 17 _3, ...) are formed in the vertical direction. The number of the scanning line wiring 16 is 1024, and the number of the modulation line wiring 17 is 1280 × 3 (× 3 corresponds to R, G, B).
The wiring pitch is 636 μm and 212 μm. A pixel is defined at each intersection of the scanning line wiring 16 and the modulation line wiring 17,
A planar electron source 12 serving as an electron-emitting device is provided. The number is 1024 in the scanning line direction and 1 in the modulation line direction.
It is 280 × 3. Discharge wiring 15 is provided around a display area in which pixels are provided in a matrix, and between the discharge wiring 15 and each of the scanning line wiring 16 and the modulation line wiring 17, the discharge type flat electron source 13 and 14 are provided.

A position indicated by a broken line 18 in FIG. 1 is a sealing region where the rear plate and the face plate are bonded, and the rear plate and the face plate are bonded with frit glass or the like after completion. At this time, the rear plate and the face plate are sealed with an interval of about several mm. The face plate is a glass substrate (second
As shown in FIG. 10, a phosphor material having emission peaks of R, G, and B is applied to the inner surface of the substrate, and the pattern is formed at a pitch corresponding to each pixel on the rear plate. It is formed with. That is, the phosphors of R, G, and B are provided at a pitch of 636 μm at 1024 in the scanning line direction and at 1280 × 3 in the modulation line direction. A thin aluminum layer is formed on the phosphor layer, and an anode voltage (usually several kV) for accelerating electrons is applied during a display operation.

After sealing both plates, an exhaust pipe is provided outside the display area, and the inside of the display cell is evacuated through the exhaust pipe. At this time, the planar electron source for discharge is formed so as to be located inside the vacuum region. Thereafter, a display IC is completed by connecting a driving IC to each wiring. Note that a voltage can be externally applied to the discharge wiring 15 via the electrode terminal 15 '. Here, the potential was set to GND. Also, a voltage can be applied from the outside to the scanning line wiring 16 via an electrode terminal 16 ', and from the modulation line wiring 17 via an electrode terminal 17'.

In this display device, the scanning line wiring 16
, A negative selection pulse voltage is sequentially applied. In synchronization with this, a positive pulse voltage corresponding to the display signal of each pixel is applied to the modulation line 17. Now, the negative pulse voltage -Vs is applied to the査線16 _1. At this time, when the applied positive pulse voltage Vh to the modulation line wiring 17 _1,
A voltage of (Vh + Vs) is applied to the plane electron source. The plane electron source 12 according to the bias voltage (Vh + Vs)
Electrons are accelerated toward the aluminum electrode of the face plate, which is the anode electrode.

The highly accelerated electrons pass through the aluminum thin film and irradiate the phosphor layer to excite the phosphor to emit light. The emission current can be controlled by the bias voltage (Vh + Vs). The electron source 12 of all the pixels connected to the scanning lines 16 ₁ since -Vs is commonly applied, the display state is controlled by the voltage Vh is applied to the modulation line wiring 17. When Vh is small, the emission current is small and the light emission luminance is small.
Conversely, when Vh is large, the amount of emission current increases and high luminance can be obtained.

The selection pulse is applied next scanning lines 16 _2, all the pixels connected thereto becomes the selected state,
By applying a display signal corresponding to the display of this row to the modulation line 17, it is possible to emit a target luminance. The scanning lines 16 are sequentially selected, and when the application of the selection pulse to all the scanning lines 16 is completed, the display of the entire screen ends, and the display operation of the next frame is performed in a similar sequence.

Here, as the display signal modulating means, the voltage value Vh of the modulation line 17 is controlled, but the amount of emitted electrons may be controlled with a pulse width while Vh is kept constant. In the present embodiment, the scanning line 1
6, 7.5 V was applied to the modulation line 17.
That is, the bias voltage of the electron source at the maximum luminance is 15V.

As described above, in the plane electron source, an emission electron current necessary for obtaining sufficient luminance can be obtained with an applied voltage of about 15 V. For this reason, it is extremely vulnerable to static electricity generated in a process after the electron source is formed, such as a process for manufacturing the rear plate or a process for assembling the face plate. For example,
Even if static electricity of about 100 V is induced, the electron source 12 has a voltage corresponding to enormous electron emission, and the electron source 12 is thermally destroyed.

In this embodiment, in order to effectively prevent such static electricity induced from the outside, the discharge electron source 1 is used.
Reference numerals 3 and 14 are provided outside the matrix area (display area), and are positions where the ingress of static electricity is first received. The most problematic of the static electricity is the instantaneous large peak current. The instantaneous large current induced outside the matrix region causes a large voltage drop due to the effect of the wiring resistance. Therefore, before a large voltage is applied to the electron source 12 inside the matrix region, an electrostatic voltage is applied to the discharge electron sources 13 and 14 to start discharging. This is because the response of the electron source is remarkably fast and discharge can be started instantaneously.

In this embodiment, the discharge electron sources 13 and
The impedance of 14 was smaller than the electron source 12 in the pixel section. FIG. 2 shows a plan view of the present electron source.
The fine particle film 23 of PdO is formed between the thin film electrodes 21 and 22 by inkjet printing or the like. Electrode 2
By performing an appropriate energization process between the first and second portions, the crack portion 24 can be formed inside the PdO pattern. The width of the crack 24 is submicron or less. Therefore, after the crack is formed, when a voltage is applied between the electrodes 21 and 22, 1 × which is sufficient to cause the field emission of electrons to the crack portion 24.
A strong electric field such as 10 ⁷ (V / cm) can be applied.

The electron emission capability of the electron source is proportional to the length 25 of the crack 24. In the present embodiment, the electron source 12 of the pixel portion
Was 70 μm, and the crack length of the discharge electron sources 13 and 14 was 700 μm. For this reason, the instantaneously induced electrostatic charges are transferred to the discharge electron source 1 having a low impedance.
The electron source 1 inside the matrix area can be discharged at 3, 14
2 could be prevented. Note that the discharge electron sources 13 and 14 were formed under exactly the same energizing conditions as the pixel portion electron source 12. Specifically, a voltage value of 10 V and a pulse width of 1 m
s, a pulse voltage having a period of 10 ms. In order to make the electron source characteristics more uniform, a similar energization treatment may be performed in an organic gas atmosphere or in a vacuum after forming the crack.
Further, it is desirable that the impedance of the discharge electron sources 13 and 14 is as low as possible.
If it is about 0 or less, there is a sufficient effect.

FIG. 3 is an enlarged view showing the configuration of the display area of the rear plate on which the electron source 12 is arranged. On a glass substrate 11, planar electron sources 12 are arranged in a matrix. The electron source 12 is formed by disposing a fine particle film (conductive thin film) 23 between the electrodes 21 and 22.
It is driven by the voltage applied between 1 and 22. Electrode 2
1 is connected to the scanning line wiring 16, and the electrode 22 is connected to the modulation line wiring 17. The flat-type electron source array shown in FIG. 3 includes a conductive thin film 23 serving as the electron source 12, electrodes 21 and 22,
All of the wirings 16 and 17 can be formed by printing. Although not shown, an insulating layer for insulating the scanning line wiring 16 and the modulation line wiring 17 is also formed between both wirings by printing. For this reason, an element array can be formed on a large-area substrate, and it is extremely promising as a large-screen flat display device.

In FIG. 3, by sequentially applying a selection pulse to the scanning line wiring 16, the selected scanning line wiring 1 is applied.
A desired voltage is applied to each of the electron sources 12 connected to 7 according to the voltage of the modulation line voltage pulse applied at the same time. Since the amount of electrons emitted from the electron source 12 can be controlled in accordance with the applied voltage, the required amount of electrons can be applied to the phosphor, and an image can be displayed.

The discharge wiring 15 in FIG. 1 gives one of the potentials of the discharge electron sources 13 and 14.
It is not necessary to apply a specific potential during the manufacturing process, and it is sufficient to keep the device electrically open. The potential at this time is normally GND like other scanning line wirings 16 and modulation line wirings 17.
Level. Once static electricity is induced in the scanning line wiring 16 or the modulation line wiring 17, static electricity is induced between the scanning line wiring 16 and the modulation line wiring 17, and the electron sources 13, 1 are generated.
4 is applied with a voltage. Further, when the discharge electron sources 13 and 14 are left as they are even after the end of the manufacturing process to protect the static electricity in the actual use state, the drive signal sequence, that is, the potential between -Vs and Vh, for example, 0 V (GND) If the potential is connected to the terminal 15 ', a stable operation can be performed.
That is, the discharge electron sources 13 and 14 may be set so as not to be in a bias state in which electrons can be emitted.

As described above, according to the present embodiment, the discharge wiring 15 is provided outside the display area, and the discharge electron source 1 is disposed between the wiring 15 and the scanning line wiring 16 and the modulation line wiring 17.
3 and 14 are connected to each other, and the static electricity is discharged by the discharge electron sources 13 and 14 before the static electricity is applied to the pixel portion electron source 12 through the scanning line wiring 16 and the modulation line wiring 17. Pixel electron source 12 due to static electricity
Can be prevented beforehand. For this reason, it is possible to reduce the causes of defective pixels and to realize a high-definition electron beam phosphor display device having no defective pixels.

In this embodiment, the discharge electron sources 13 and
Since the electron source 14 can be formed at the same time as the pixel electron source 12, the manufacturing process does not become complicated due to the addition of the discharge electron sources 13 and 14. Further, a discharge electron source 1
Since the current driving capabilities of the pixel portions 3 and 14 are made larger than those of the pixel portion electron sources 12, a relatively large amount of charge can flow through the discharge electron sources 13 and 14.
Can be more reliably protected.

(Second Embodiment) FIG. 4 shows a second embodiment of the present invention.
It is a figure which shows the structure of the rear plate of the electron beam excitation phosphor display device concerning embodiment 2 in planar view. The same parts as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof will be omitted.

This embodiment differs from the first embodiment described above in that a plurality of discharge common wirings 15 are provided. That is, similarly to the first embodiment, the discharge electron sources 13 and 14 are provided outside the matrix region, but in this embodiment, five horizontal discharge common wires 15 (15
_1, 15 _2, ...) provided, discharge electron source 14 is also modulated line wiring 1
7, five common lines 15 for discharge are sequentially selected and connected. In the drawing, only two lines 15 ₁ and 15 ₂ are shown, and the connection of the discharge electron source 14 is shown as an example of two common lines.

The reason why a plurality of the discharge common wirings 15 are provided is that a current of 1 mA flows for each electron source having a crack length of 700 μm when the above-mentioned crack portion of the electron source is formed. When a crack is formed, a large current is required, and the voltage drop of the wiring causes non-uniformity in the electron source characteristics.

In this embodiment, 1280 × 3 in the horizontal direction
= 3840 electron sources 14 are arranged. For this reason, a current of 3.84 A flows when the number of the common wirings 15 for discharge is one. However, in this embodiment divided into five common wirings 15, the current becomes 0.77 A per one, and a voltage drop occurs. The non-uniformity of the electron source 14 due to the above can be eliminated. The pixel portion has a crack length of 70 μm, and the pulse current per scanning line is as small as 0.38 A, so that a uniform electron source 12 can be formed.

The number of divisions of the discharge common wiring 15 may be determined based on the design specification of the display device, and the position may be divided into upper and lower portions of the display section, or the energization process may be performed simultaneously from the left and right sides of the common wiring 15. The voltage drop may be reduced.

(Third Embodiment) Next, an electron beam excited phosphor display device according to a third embodiment of the present invention will be described.

The basic configuration of this embodiment is the same as that of FIG. 4, and the drawing is omitted. Here, the electron source 1 in the display area
2 and the characteristics of the discharge electron source 14 are different as shown in FIG. FIG. 5 shows the current-voltage characteristics of the electron source. In the present embodiment, the characteristics of the electron source 12 in the display area are shown in the element 1, and the characteristics of the discharge electron source 14 are shown in the element 2. In other words, the electron emission characteristics of the discharge electron source 14 are shifted to a lower voltage side, so that a current can flow more at the same voltage. This is a step of forming a crack in the electron source, that is, Pd.
The adjustment was made by changing the conditions for energization for forming a crack in the O film, the conditions for energization in an organic gas atmosphere, or the conditions for aging in vacuum.

Since the discharge electron sources 13 and 14 of this embodiment can discharge electrostatic charges by applying a lower voltage, the length of the crack can be made shorter than that of the first embodiment. In the present embodiment, the crack length of the discharge electron sources 13 and 14 is 200 μm, while the crack length of the electron source 12 in the pixel portion is 70 μm. The threshold voltage at which the current of the electron source starts flowing is adjusted to 10 V for the electron source 12 in the pixel portion and to 8 V for the electron sources for discharge 13 and 14. The current value that can flow when the same voltage is applied is about 20 times that of the discharge electron sources 13 and 14 compared to the pixel. For this reason, the discharge electron sources 13 and 14 have a shorter crack length than that of the first embodiment, but have about twice the capacity, and have a high ability to protect against static electricity.

Although the discharge electron sources 13 and 14 do not affect the display operation after the end of the manufacturing process,
Present as a leakage current path. When it is desired to separate these discharge electron sources 13 and 14 in a circuit after the end of the manufacturing process in order to reduce power consumption, the following procedure can be used. In particular, when the threshold voltage of the discharge electron sources 13 and 14 is lower than that of the pixel portion as in the present embodiment, the power consumption of the discharge electron sources 13 and 14 may not be ignored.

As a method for circuit separation, an adjustment voltage Va is applied to the discharge electron sources 13 and 14 as shown in FIG. As Va is increased, the element current also increases, and the element is thermally destroyed at a certain point. Breakage in this case results in characteristic deterioration in which the crack width increases and the current greatly decreases. In other words, it does not have an adverse effect on the operation by approaching the open state electrically. This is the feature of the electron emission electron source, and the most problematic electrical short circuit does not occur. This feature is also at the time of discharging static electricity, and when discharging a large amount of electrostatic charge, sometimes the discharge electron source may be destroyed. No defects are induced.

(Fourth Embodiment) In the first to third embodiments, a planar electron source using a crack provided in a thin-film conductor layer was used as an electron-emitting device. A projecting electron source using a projecting emitter electrode was used as an emission element. FIG. 7 shows a sectional structural view of the projection type electron source. A wiring electrode 73 formed on an insulating substrate 11, a conical conductive emitter 72 formed thereon, and a gate electrode layer 74 formed thereon with an insulating layer 75 interposed therebetween
Consists of The gate electrode layer 74 has a circular opening 77 centered on the tip 76 of the emitter 72.

The operation of the projection type emitter is determined by the operation of the gate electrode 74.
When a positive voltage is applied to the emitter electrode 73, the electric field concentrates on the emitter tip 76, and the emitter tip 76
A strong electric field greater than the distance between the gate electrode opening and the gate electrode opening is induced in the emitter tip 76. The magnitude of the electric field concentration changes depending on the sharpness of the emitter tip 76 and the size of the opening of the gate electrode 74. In general, when the radius of curvature is 50 nm and the diameter of the gate opening is about 1 μm, Electrons can be emitted from the emitter tip 86 when the voltage is about several tens to 100V.

The field emission start voltage Vth can be reduced by increasing the sharpness, reducing the size of the gate opening, or reducing the work function of the emitter material. However, Vth is generally higher than that of the above-mentioned flat electron source. For this reason, it can be said that the projection type electron source array is less susceptible to static electricity than the flat type, but
Nevertheless, the destruction by static electricity could not be completely eliminated.

FIG. 8 is a plan view showing a configuration of a rear plate of an electron beam excited fluorescent display device using a projection type electron source according to a fourth embodiment of the present invention. The same parts as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof will be omitted.

As in the first embodiment, the insulating substrate 11
The scanning line wiring 16 and the modulation line wiring 17 are arranged thereon, and the projection type electron source 82 is provided at a pixel portion defined at each intersection thereof. The number of the scanning line wiring 16 is 480, the number of the modulation line wiring 17 is 640 × 3, and the pixel pitch is 630 μ in the vertical direction.
m, 210 × 3 μm in the horizontal direction. The electron source 82 is composed of 625 projection-type emitters for each pixel, the average diameter of the gate opening is 0.7 μm, the average radius of curvature of the tip of the emitter is 20 nm, and the projection is formed by molybdenum rotary evaporation. Vth of the electron source was about 70V.

The discharge electron sources 83 and 84 are provided in the pixel section electron source 8.
2 was formed in an outer region arranged in a matrix with a configuration shown by an equivalent circuit in FIG. That is, an electron source having a configuration in which the gate / emitter electrodes of the projection type electron sources are opposite to each other is connected in parallel between each scanning line wiring 16 and modulation line wiring 17 and the common discharge wiring 15. In the projection type electron source, since the electron emission is performed from the tip of the emitter,
There is polarity dependence of the device. On the other hand, since the polarity of the static electricity induced from the outside has positive and negative polarities, such a configuration of the discharge electron source is optimal to effectively discharge the charge with respect to both types of static electricity. It is. In a flat-type electron source, since the electron emission characteristics of the element do not basically have polarity dependency, a discharge circuit can be realized with the configuration as shown in FIG.

Each of the discharge electron sources shown in FIG. 8 was composed of 6,250 projection-type emitters. The average diameter of the gate opening was set to 0.6 μm, and Vth was set to 65 V. FIG. 9 shows the characteristics of the pixel portion electron source and the characteristics of the discharge electron source at this time. In the figure, element 1 is the characteristic of the pixel section electron source 82, and element 2 is the characteristic of the discharge electron sources 83 and 84. The discharge electron sources 83 and 84 have both positive and negative characteristics, a low electron emission start voltage, and a higher current driving capability than the pixel portion. Therefore, the electrostatic charge induced from the outside can be more effectively discharged to prevent the pixel unit electron source 82 from being broken.

The present invention is not limited to the above embodiments. In the embodiment, each of the planar electron source and the projection electron source has been described. However, the electron source is not limited to these, and can be appropriately changed according to specifications. Further, the first substrate constituting the rear plate is not necessarily limited to a glass substrate, but may be an insulating substrate. Further, the second substrate constituting the face plate is not limited to a glass substrate, but may be any transparent substrate that sufficiently transmits the fluorescence generated by the phosphor.
In addition, various modifications can be made without departing from the scope of the present invention.

[0061]

As described above in detail, according to the present invention, a display region comprising a set of pixel portions is formed on a first substrate on which scanning line wiring, modulation line wiring, and display electron-emitting devices are formed. Is provided outside, and the discharge electron-emitting device is connected between the common line and each of the scanning line wiring and the modulation line wiring. Can be effectively prevented. Therefore, destruction of the electron source due to static electricity can be prevented, and a high-definition electron beam phosphor display device having no defective pixels can be realized.

[Brief description of the drawings]

FIG. 1 is a plan view showing a configuration of a rear plate of an electron beam excited phosphor display device using a planar electron source according to a first embodiment.

FIG. 2 is a plan view showing a configuration of a flat-type electron source used in the first embodiment.

FIG. 3 is a plan view showing a state where the flat electron source of FIG. 2 is arranged on a rear plate.

FIG. 4 is a plan view showing a configuration of a rear plate of an electron beam-excited phosphor display device using a planar electron source according to a second embodiment.

FIG. 5 shows a current of a planar electron source according to the third embodiment.
The figure which shows a voltage characteristic.

FIG. 6 shows the current of the planar electron source according to the third embodiment.
The figure which shows a voltage characteristic. To destroy the electron source for discharge

FIG. 7 is a sectional view showing a configuration of a projection type electron source used in a fourth embodiment.

FIG. 8 is a plan view showing a configuration of a rear plate of an electron beam excited fluorescent display device using a projection type electron source according to a fourth embodiment.

FIG. 9 shows the current of the projection type electron source according to the fourth embodiment.
The figure which shows a voltage characteristic.

FIG. 10 is a cross-sectional view showing a main configuration of a conventional electron beam excited phosphor display device using a flat electron source.

FIG. 11 is a plan view showing the configuration of a rear plate of a conventional electron beam excited phosphor display device using a flat electron source.

FIG. 12 is a cross-sectional view showing a main configuration of an electron beam excited phosphor display device using a conventional projection electron source.

[Explanation of symbols]

Reference numeral 11: glass substrate (rear plate: first substrate) 12, 82: pixel portion electron source (electron emission device for display) 13, 14, 73, 74 ... electron source for discharge (electron emission device for discharge) 15: discharge use common interconnection 16 (16 _1, 16 _2, 16 _3, ...) ... scanning lines 17 (17 _1, 17 _2, 17 _3, ...) ... modulation line wiring 18 ... vacuum seal portion 21, 22 ... electrode 23 ... conductive Functional thin film 24 Crack 31 Glass substrate (face plate: second substrate) 32 Phosphor film 33 Anode electrode 72 Emitter 73 Emitter electrode 74 Gate electrode 75 Interlayer insulating film 76 Emitter tip

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5C031 DD17 5C032 AA01 5C036 EE09 EE19 EF01 EF06 EF09 EG12 EH04 EH08

Claims (7)

[Claims] A plurality of scanning lines which are formed on a first substrate on a surface facing a second substrate, the first and second substrates being opposed to each other at a predetermined interval; Wiring, a plurality of parallel modulation line wirings formed on the first substrate on the side facing the second substrate in a direction crossing the scanning line wiring, and the scanning line wiring and the modulation line A display electron-emitting device formed in a pixel portion defined at each intersection of wiring, one electrode being connected to the scanning line wiring, and the other electrode being connected to the modulation line wiring, and A common line formed outside the display area, a discharge electron-emitting device connected between each of the scanning line line and the modulation line line, and the common line, and a surface facing the first substrate. A phosphor layer and an anode electrode provided on the second substrate on the side of An electron beam-excited phosphor display device, comprising: 2. The electron beam excitation device according to claim 1, wherein said common lines are arranged in parallel, and said discharge electron-emitting devices are selectively connected to said common lines arranged in parallel. Phosphor display device. 3. The electron beam excitation device according to claim 1, wherein each of said display and discharge electron-emitting devices comprises a conductive thin film and an electron-emitting portion formed in said thin film. Phosphor display device. 4. The display electron-emitting device according to claim 1, wherein a plurality of basic devices each comprising a projection-type emitter electrode and a gate electrode having a circular opening centered on a tip of the projection of the emitter electrode are arranged. 2. The electron beam according to claim 1, wherein the discharge electron-emitting device includes a plurality of basic unit elements each including two basic elements in which the basic elements are connected in parallel in opposite directions. Excitation phosphor display. 5. The device according to claim 4, wherein the number of projection-type emitter electrodes constituting the discharge electron-emitting device is larger than the number of projection-type emitter electrodes constituting the display electron-emitting device. Electron beam excited phosphor display. 6. The electron beam excited fluorescence according to claim 1, wherein the current driving capability of the discharge electron-emitting device is larger than the current driving capability of the display electron-emitting device. Body display device. 7. The electron beam according to claim 1, wherein an electron emission start voltage of said discharge electron emission element is lower than an electron emission start voltage of said display electron emission element. Excitation phosphor display.