JPH11317182A - Image display device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To prevent discharge and increase the creeping distance between a high-voltage introduction wire and a face plate or a rear plate, and to display an image which does not cause deterioration of the low-melting glass due to movement of sodium ions and the like. It is an object to provide a device. SOLUTION: The airtight container is constituted by two flat substrates made of an insulating material arranged to face each other, and an outer frame provided between the two substrates, wherein the airtight container includes: At least an exhaust pipe for exhausting the airtight container, a phosphor, an anode unit, and an excitation source of the phosphor are provided, and electrons emitted from the phosphor excitation source are applied to the anode unit formed on the substrate. Accelerated by the applied voltage, in a flat panel type image display device that collides with the phosphor and displays an image, a high-voltage introduction line to be applied to the anode portion is taken out of the airtight container through the exhaust pipe. It is characterized by being.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a flat panel image display device using electrons generated from a phosphor excitation source for displaying a thin large screen.

[0002]

2. Description of the Related Art In recent years, a thin flat panel display has attracted attention as an image display device replacing a heavy CRT (CRT). Flat panel displays include those using liquid crystal, electroluminescence, and the like, and those using electrons, and are required to have a large size. As a self-luminous flat panel display using electrons, a cold cathode electron-emitting device, a thermionic electron-emitting device, or the like is known as a phosphor excitation source for exciting a phosphor.

Heretofore, the applicant has filed many applications for flat panel displays using surface conduction electron-emitting devices. FIG. 4 is a partial cross-sectional view showing one configuration example of a conventional flat panel display.

In FIG. 4, reference numeral 401 denotes a substrate made of an insulating material such as blue sheet glass or soda glass; 402, a surface conduction electron-emitting device having an electron-emitting portion; Phosphor 405 covered with an anode (metal back) 404 for accelerating electrons
Is a face plate made of an insulating material such as soda glass having an inner surface of an airtight container. Here, the substrate 401 and the surface conduction electron-emitting device 40 formed on the substrate 401
2. The term “rear plate 400” includes the wiring for driving the surface conduction electron-emitting device 402 and the like.

[0005] An outer frame 40 made of an insulating material such as glass is provided between the face plate 403 and the rear plate 400.
7 is provided, and an airtight container is formed by joining each end face of the outer frame 407 to the face plate 403 and the rear plate 400. The bonding portion 408 is bonded by using low melting point glass, ultrasonic solder, ultraviolet curing resin, or the like. Also,
An exhaust pipe 409 exhausts the inside of the envelope of the airtight container.
420 is an introduction line for applying a high voltage to the metal back 404, and 421 is a cable for supplying a high voltage to the introduction line from an external high-voltage power supply.

FIG. 5 schematically shows the surface conduction electron-emitting device 402. FIG. 5A is a plan view of the surface conduction electron-emitting device, and FIG. 5B is a cross-sectional view taken along a plane AB shown in FIG. 5A. In FIG. 5, reference numeral 500 denotes a substrate;
502 is an element wiring, 503 and 504 are element electrodes,
The electrode is made of Au and has a thickness of 0.1 μm. Also, 50
Reference numeral 5 denotes a conductive thin film, which is a fine particle mainly composed of PdO (palladium oxide) formed by applying a solution containing organic Pd (palladium / ccP4230; manufactured by Okuno Pharmaceutical Co., Ltd.), which is an organic metal solution, and then heating. It is a thin film. Also, 50
Reference numeral 6 denotes an electron emitting portion.

Next, a method of manufacturing the image display device will be described. First, device wirings 501 and 502 and a surface conduction electron-emitting device 402 are formed on blue glass substrates 401 and 500. Next, the upper and lower end surfaces of the outer frame 407 and the exhaust pipe 409
And low-melting glass (LS-3)
081; Nippon Electric Glass Co., Ltd.) dissolved in an organic binder is preliminarily applied and calcined. Next, the respective components are combined and subjected to main firing in an electric furnace to complete the envelope. After the exhaust pipe 409 is connected to a vacuum pump and the inside of the container is evacuated to about 2 × 10 ⁻⁵ Pa, a voltage is applied through the element wirings 501 and 502 of the surface-conduction electron-emitting device 403 and the 506 is formed. Electron emission unit 50
After forming 6, the envelope is heated while being evacuated to remove residual gas in the container.

When the degree of vacuum in the container reaches 1 × 10 ⁻⁷ Pa or less, the exhaust pipe 409 is heated with a gas burner and sealed to obtain an airtight container. Thereafter, the getter is heated by high frequency from outside the airtight container and activated to complete the airtight container. Getter is a metal that has the function of maintaining and improving the vacuum in an airtight container by activating it.
There are two types: an evaporative type mainly composed of aluminum or the like and a non-evaporable type mainly composed of iron-nickel or the like. Finally, a high-voltage power supply (not shown) is connected to the cable 421 by element wiring 501 and
A drive circuit (not shown) is connected to 502 to complete the image display device.

The electron emitting portion 506 is formed by a known method disclosed in Japanese Patent Application Laid-Open No. 7-235255.

Hereinafter, the operation of the image display device will be described. The surface conduction electron-emitting device 402 is driven by an external driving circuit to emit electrons. The emitted electrons are attracted to the face plate 403 by a high voltage (several to several tens of kV) applied to the metal back 404 from an external power supply via the lead wire 420 and the cable 421, and the metal back 404 and the phosphor 405. To excite the phosphor 405 to emit visible light.

[0011]

However, since the conventional image display device is very thin compared to a CRT or the like, the high-voltage lead-in 420 applied to the metal back 404, the face plate 403, and the rear The creepage distance with the plate 400 is reduced, and the potential on the surface of the image display device becomes unstable or discharge occurs.

The high voltage is applied to the outer frame 407 and the joint 4
08, it is drawn out of the hermetic container, so that when a high voltage is applied to the metal back 404, the space between the rear plate 400 and the lead-in line 420, that is, the outer frame 40
7, a high electric field is generated inside the insulating member, for example, in the case of soda lime glass, sodium diffused inside the soda lime glass moves under the influence of the high electric field, and current leaks or deterioration of the low melting point glass (Japanese Patent Laid-Open No. 6-1994). 139,972) and the like, leading to damage to the image display device.

The present invention solves the above-mentioned conventional problems. By increasing the creepage distance between the high-voltage introduction line and the face plate or the rear plate, it is possible to prevent discharge and to reduce the melting point due to the movement of sodium ions and the like. An object of the present invention is to provide an image display device that does not cause deterioration of glass.

[0014]

To achieve the above object, a flat panel display according to the present invention has the following arrangement.

(1) An airtight container composed of two flat substrates made of an insulating material opposed to each other and an outer frame provided between the two substrates, wherein the airtight container is airtight. It has at least an exhaust pipe for evacuating the container, a phosphor, an anode part and a phosphor excitation source, and electrons emitted from the phosphor excitation source are accelerated by a voltage applied to the anode part formed on the substrate. In a flat-panel image display device that collides with a phosphor and displays an image, a high-voltage introduction line to be applied to the anode portion is taken out of the hermetic container through an exhaust pipe.

(2) The exhaust pipe for taking out the introduction line is provided on a substrate facing the substrate having the phosphor.

(3) A surface conduction electron-emitting device is used as the phosphor excitation source.

(4) The flat substrate is a face plate provided with the anode part and a rear plate provided with the phosphor excitation source. The exhaust pipe from which the high-voltage lead is taken out is the outer frame. Alternatively, it is characterized by being arranged on a face plate and a rear plate.

[Operation] The operation of the above means is as follows.

By introducing a high-voltage introduction line to be applied to the anode portion formed on the face plate to the outside of the airtight container through an exhaust pipe, (1) introduction of a high voltage between the face plate and the rear plate The creepage distance with the line can be increased, and the discharge can be suppressed. (2) By applying a high voltage to the high-voltage introduction line, a high electric field that has conventionally occurred inside the outer frame material is not generated, and inexpensive soda lime glass or the like can be used for the outer frame material.

In addition, since the exhaust pipe for taking out the lead wire is provided on the substrate facing the substrate having the phosphor, the high-voltage cable can be easily routed outside the hermetic container, and a safe image can be obtained. A display device can be obtained.

Further, by using a surface conduction electron-emitting device as a phosphor excitation source, a flat-panel image display device with a narrow interval can be obtained, and the effect of the above-described operation is increased.

[0023]

Embodiments of the present invention will be described below in detail with reference to the drawings.

(First Embodiment) FIG. 1 is a sectional view of a side portion of a flat panel display according to a first embodiment of the present invention.

In FIG. 1, reference numeral 101 denotes a blue glass substrate;
Electron-emitting devices 102 are formed in a matrix on a substrate 101 (hereinafter, referred to as a rear plate 100). Numeral 103 denotes a phosphor 105 covered with an anode (metal back) 104 on a substrate made of an insulating material such as blue plate glass.
Is an outer frame for maintaining the rear plate 100 and the face plate 103 at a predetermined distance (7 mm in this embodiment). Face plate 103, rear plate 10
The outer frame 107 and the outer frame 107 are joined together at a joining portion 108 to form an envelope. Reference numeral 109 denotes an exhaust pipe for exhausting the inside of the envelope. In the present embodiment, soda lime glass having an outer diameter of 4 mm and an inner diameter of 2 mm is used. Reference numeral 120 denotes an introduction line for applying a high voltage to the anode unit 104 from the outside of the airtight container penetrating through the exhaust pipe 109, and is a Sylvanian # 4.
(Fe-Ni-Cr alloy) wire diameter of 1 mm was used. High voltage (several to tens of kV) supplied from a high voltage power supply (not shown)
Is the anode part 104 via the cable 121 and the lead-in wire 120.
Is applied.

Hereinafter, a method of manufacturing the above-described image display device will be described.

First, the electron-emitting device 1 is previously placed on the substrate 101.
02 is formed as a rear plate 100. On the other hand, on the face plate 103 side, the introduction wire 120 is connected to the anode section 10.
4 and joined. Next, a solution in which low-melting glass (LS-3081; manufactured by Nippon Electric Glass Co., Ltd.) was previously melted with a binder was applied to the joint portion 108 of the rear plate 100, the face plate 103, the outer frame 107, and the exhaust pipe 109. Preliminary firing is performed. Thereafter, the respective positions were adjusted and fixed, and the main firing was performed in an electric furnace at 410 ° C. for 15 minutes to obtain an envelope.

After all the members are fixed, the envelope is exhausted from the exhaust pipe 109 while baking the envelope at 200 ° C. At this time, a getter (not shown) also emits gas from the outside of the envelope by high-frequency induction heating. In the present embodiment, an evaporable getter mainly containing Ba-Al is used.
After baking, the pressure in the container is about 1 × 10 ⁻⁵ Pa
When the temperature reaches the following, the exhaust pipe 109 is burned with a burner, and when the glass is softened, the exhaust pipe 109 is picked up from both sides to be hermetically sealed with the introduction wire. After sealing the exhaust pipe, the getter is heated and activated again by high-frequency induction heating from outside the hermetic container to complete the hermetic container. After completing the hermetic container, a high-voltage cable 121 and an electron-emitting device 102
Then, an external drive circuit (not shown) and the like were connected to complete the image display device.

In this embodiment, Ba-A is used as the getter material.
Although the evaporation type having l as a main component is used, for example, a non-evaporation type getter having Ti (titanium), Zr (zirconium), Fe (iron), Ni (nickel), V (vanadium), or the like as a main component may be used. However, the present invention is not limited to these.

In this embodiment, low-melting-point glass is used as a sealing material for the face plate, the rear plate, the outer frame, and the like. Is not particularly limited as long as it is a sealing material and a fixing material that can maintain the airtight state.

In this embodiment, Sylvania # 4 (Fe-Ni-Cr) is used as the introduction wire. However, any conductive material having an expansion coefficient similar to that of the exhaust pipe material of the exhaust pipe 9 is not particularly limited. Not done. When the exhaust pipe material is blue sheet glass,
For example, there are a chrome wire, a dumet wire, a platinum wire, a titanium wire and the like.

In the flat-panel image display device configured as described above, the creepage distance between the high-voltage introduction line 120 applied to the metal back 104, the face plate 103 and the rear plate 100 is increased, and the image display device A good image display device with stable surface potential and no discharge was obtained. Also, movement of sodium in the outer frame and breakage of the low-melting glass were not confirmed.

(Second Embodiment) FIG. 2 is a sectional view of a side portion of a flat panel display according to a second embodiment of the present invention.

This embodiment has substantially the same configuration as the above-described first embodiment. A face plate 203 on which a phosphor 205 and a metal back 204 are formed,
As in the first embodiment, the rear plate 200 on which the surface conduction electron-emitting devices 202 and the like are formed is sealed to the outer frame 207 with low-melting glass at each of the peripheral joints 208 to form an envelope. Was formed. An evaporative ring getter (not shown) mainly composed of barium-aluminum was arranged in the envelope.

While the inside of the container was evacuated by the exhaust pipe 209, the envelope was heated at 200 ° C. for 10 hours. Thereafter, when the pressure in the envelope reaches 1 × 10 ⁻⁵ Pa or less,
The exhaust pipe material of the exhaust pipe 9 is softened by resistance heating, and the
20 and sealed. After sealing, the getter was heated by high-frequency induction heating and activated to complete an airtight container.

In this embodiment, the exhaust pipe 209 is provided on the face plate 203 side. The exhaust pipe used was soda lime glass having an outer diameter of 12 mm and an inner diameter of 8 mm, and the introduction wire 220 was a Dumet wire (Fe-Ni-Cu) having a wire diameter of 2 mm. 221 is an introduction line 2 from an external high voltage power supply (not shown).
20 is a cable for supplying a high voltage to the cable 20.

In the flat-panel image display device configured as described above, in addition to the effects of the first embodiment, it is possible to reduce the thickness of the image display device, and to reduce the exhaust gas accompanying an increase in the diameter of the exhaust pipe. Improvements in cost, such as shortening of time, were observed.

(Third Embodiment) FIG. 3 is a sectional view of a side surface portion of a flat panel display according to a third embodiment of the present invention.

The present embodiment has substantially the same configuration as the above-described first and second embodiments. Phosphor 3
As in the first embodiment, a face plate 303 having a metal back 304 and a metal back 304 and a rear plate 300 having a surface conduction electron-emitting device 302 are connected to the outer frame 307 at each peripheral joint 308 by a low melting point. Sealed with glass to form an envelope. A getter (not shown) was provided in the envelope, and the inside of the container was evacuated by an exhaust pipe 309 to make the container airtight and then activated.

In this embodiment, the exhaust pipe 309 is provided on the rear plate 303 side. Exhaust pipe 309 and introduction line 320
The same one as in the second embodiment was used.

In the flat-panel image display device configured as described above, in addition to the effects of the first and second embodiments, the introduction line 3
The cable 321 for supplying a high voltage to the cable 20 has been easily routed. In addition, in the second embodiment, the exhaust pipe 9 is provided on the front plate side on the image display side, but in the present embodiment, the introduction line is drawn out together with the exhaust pipe on the rear plate side, so that it does not interfere with the visual sense. Instead, it can be made thinner.

[0042]

The present invention has the following effects by using the above-described structure.

The first effect of the present invention is that the high voltage introduction line applied to the anode portion formed on the face plate is taken out of the hermetic container through the exhaust pipe, so that the face plate and the rear plate are removed. The creepage distance between the plate and the lead-in line can be increased, and the surface potential of the image display device can be stabilized, and discharge can be suppressed. In addition, since no electric field is generated inside the outer frame material, inexpensive soda lime glass can be used.

A second effect of the present invention is that the cable for high voltage applied to the anode portion is arranged on the inner side surface of the hermetic container, so that the cable can be easily routed outside the hermetic container. Was.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional side view showing a first embodiment of a flat panel display according to the present invention.

FIG. 2 is a partial cross-sectional side view showing a second embodiment of the flat panel display according to the present invention.

FIG. 3 is a partial side sectional view showing a third embodiment of the flat panel display according to the present invention.

FIG. 4 is a partial side sectional view showing a conventional flat panel image display device.

FIG. 5 is a schematic view of a surface conduction electron-emitting device.

[Explanation of symbols]

100, 200, 300, 400 Rear plate 101, 201, 301, 401 Substrate 103, 203, 303, 403 Face plate 104, 204, 304, 404 Anode part (metal back) 105, 205, 305, 405 Phosphor 107, 207, 307, 407 Outer frame 108, 208, 308, 408 Joint 109, 209, 309, 409 Exhaust pipe 120, 220, 320, 420 Introductory line 121, 221, 321, 421 Cable 102 Electron emitting element 202, 302, 402 surface conduction electron-emitting device

Claims (6)

[Claims] 1. An airtight container comprising two flat substrates made of an insulating material disposed to face each other and an outer frame provided between the two substrates, wherein the airtight container comprises: An exhaust pipe for exhausting the inside of the hermetic container, a phosphor, an anode portion and at least an excitation source of the phosphor, wherein the electrons emitted from the phosphor excitation source are formed on the anode portion formed on the substrate. In an image display device which is accelerated by an applied voltage and collides with the phosphor to display an image, a high-voltage introduction line to be applied to the anode portion is taken out of the hermetic container through the exhaust pipe. An image display device characterized by the above-mentioned. 2. The image display device according to claim 1, wherein the exhaust pipe is provided on a substrate facing the substrate having the phosphor. 3. The image display device according to claim 1, wherein said phosphor excitation source is a surface conduction electron-emitting device. 4. The image display device according to claim 1, wherein the flat substrate is a face plate having the anode portion and a rear plate having the phosphor excitation source. An image display device, wherein the exhaust pipe from which the high-voltage lead-in wire is taken out is disposed in the outer frame. 5. The image display device according to claim 1, wherein the flat substrate is a face plate having the anode portion and a rear plate having the phosphor excitation source. The image display device, wherein the exhaust pipe from which the high-voltage introduction line is taken out is disposed on the face plate. 6. The image display device according to claim 1, wherein the flat substrate is a face plate having the anode portion and a rear plate having the phosphor excitation source. The image display device, wherein the exhaust pipe from which the high-voltage introduction line is taken out is disposed on the rear plate.