JPH06176698A - Gas electric discharge tube - Google Patents

Abstract

PURPOSE:To provide a matrix type gas electric discharge tube which operates at a relatively low discharge keeping voltage of 3OV or so by reducing the amount by which each insulating barrier is charged with positive ions generated inside a discharge space, and enhancing the ratio of charging of a cathode surface. CONSTITUTION:A number of band cathodes 19 are arranged in one direction on the inside surface of the back glass plate 18 of a gas-sealed flat envelope 17, and a number of band anodes 19 three-dimensionally intersecting the cathodes 19 are arranged on the inside surface of the front glass plate 20 of the flat envelope 17, and narrow insulating barriers 23 are provided among the anodes. The cathodes 19 are of tunnel effect type and their electron emission area 27 is provided in a position which should not be near the insulating barriers 23.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas discharge tube having a tunnel effect type electron emitting element as a cathode.

[0002]

2. Description of the Related Art A gas discharge tube having a tunnel effect type electron emitting element as a cathode is constructed as shown in FIG. That is, the conductor substrate 2 provided on the glass plate 1 constitutes the cathode 4 which is a tunnel effect type electron-emitting device together with the dielectric thin film 3 covering the surface thereof, and the cathode 4 sandwiches the discharge space 5 therebetween. It faces the anode 6, which is enclosed in a gas-filled glass envelope 7. Reference numeral 8 represents a DC power supply.

A DC voltage is applied between the cathode 4 and the anode 6 so that the latter has a positive polarity, so that gas cations 9 are generated in the discharge space 5, and the cations 9 are generated.
It moves at a low speed due to a slight potential gradient applied to and is charged on the surface of the cathode 4. As a result, the dielectric thin film 3
A strong electric field in the direction of thickness is generated in the direction, and electrons 10 are emitted due to the tunnel effect.

Some of the electrons 10 are neutralized with the cations 9, but the rest collide with the gas in the discharge space 5 to generate new cations 9, which are charged on the surface of the cathode 4. To be done. Then, since the ion supply and the electron emission are kept in equilibrium, most of the DC voltage is applied to the dielectric thin film 3. Therefore, the sustaining voltage of about 30 V is sufficient, which is a fraction of the sustaining voltage in a gas discharge tube using a normal cold cathode.
Is.

[0005]

However, when the tunnel effect type cathode is used for the cathode in the dot matrix type gas discharge tube for display, the following problems occur.
That is, in this case, as shown in FIG. 5, a discharge space 13 is formed at a three-dimensional intersection of a large number of strip-shaped cathodes 11 and strip-shaped anodes 12, and an insulating partition 14 for partitioning each anode 12 serves as a cathode 11.
The surface of the cathode 11 is in contact with the surface of the cathode 11. Therefore, some of the cations 15 generated in the discharge space 13 are not charged on the surface of the cathode 11 but are charged on the side surface of the insulating partition 14, and the cations 15 to be charged on the surface of the cathode 11 are charged. Insufficient amount. Therefore, it is necessary to increase the discharge voltage to increase the electric field strength applied to the discharge space 13 and increase the amount of cations 15 generated.
Then, the discharge sustaining voltage also becomes high, and the desired low voltage operation cannot be obtained satisfactorily. 16 is an electron.

[0006]

According to the present invention, a large number of strip-shaped cathodes are arranged in one direction on an inner surface of a rear glass plate of a gas-enclosed flat envelope, and a plurality of strip-shaped cathodes intersect three-dimensionally with the cathodes. In a gas discharge tube in which anodes are arranged on the inner surface of the front glass plate of the flat envelope, and each anode is separated from other anodes by elongated insulating barriers provided between the anodes, a tunnel effect type cathode is provided for the cathodes. And use
The electron emission region is provided at a position avoiding the vicinity of the insulating partition.

[0007]

With this structure, since the electron emission region of the cathode is located away from the insulating partition, cations are not generated in the vicinity of the insulating partition, and the cations generated in the discharge space are charged to the cathode surface. Can be increased. Therefore, it is not necessary to particularly increase the electric field strength, and it is possible to obtain a matrix type gas discharge tube that operates at a relatively low discharge sustaining voltage of about 30V.

[0008]

The present invention will be described below with reference to the illustrated embodiments. The flat envelope 17 shown in FIG. 1 contains a gas consisting mainly of neon at about 60 Torr. It is sealed with the gas pressure of
A large number of strip cathodes 19 are arranged on the inner surface of the rear glass plate 18. The cathode 19 is the front glass plate 2 of the envelope 17.
A plurality of strip-shaped anodes 21 arrayed on the inner surface of 0 intersect with each other, and a discharge space 22 is set in each of the many intersections. Each anode 21 is a thin 0.2 μm ITO film.
It is made of a film (transparent conductive film) and is separated from other anodes 21 by elongated insulating partition walls 23 provided between them. The insulating partition 23 can be obtained by subjecting the front glass plate 20 to etching, but it may be formed of an insulating film such as SiO ₂ .

Each cathode 19 has a conductor substrate 24 made of aluminum and having a film thickness of 5 μm, and a film thickness of 500 A covering the surface thereof.
Of the dielectric thin film 25 made of MgO, which is partially covered by an insulating film 26 protruding from the lower surface of the insulating partition wall 23 to both sides with a width not exceeding 1 mm. There is. The insulating film 26 has a film thickness of 0.2 μ
m of SiO ₂ and covers the vicinity of the insulating partition 23 on the surface of the cathode 19. Therefore, the substantial electron emission region 27 of the cathode 19 does not exist in the vicinity of the insulating partition 23, but exists only at a position apart from the insulating partition 23, that is, at a position facing the anode 21.

In the dot-matrix type gas discharge tube constructed as described above, the cations of the gas generated in the discharge space 22 are charged in the electron emission region 27 while being hardly charged in the insulating partition wall 23. It That is, since the charge rate of cations on the cathode surface is increased, it is possible to obtain a matrix type gas discharge tube that operates at a low discharge sustaining voltage.

Another embodiment of the present invention is shown in FIG. In this case, the difference from the configuration shown in FIG. 1 is that the dielectric thin film 25 of the cathode 19 is provided intermittently, and the insulating film 2
6 is not provided, and other configurations are the same. The dielectric thin film 25 is provided only in a portion exceeding 1 mm from the insulating partition 23. That is, the dielectric thin film 25 is provided at a position avoiding the insulating partition 23, and the conductive substrate 24 near the insulating partition 23 is exposed to the discharge space 22.

The electron emission of the tunnel effect type electron-emitting device does not occur unless the dielectric thin film 25 is present. Therefore, the charge rate of cations on the cathode surface can be increased without using the insulating film as in the above-mentioned embodiment, and in this case also, the discharge sustaining voltage can be set to about 30V.

In the above-mentioned embodiment, the reason why the distance from the insulating partition 22 to the electron emitting portion is set to 1 mm is that there is no merit even if the distance is exceeded. According to the experiment, as shown in FIG. 3, the discharge sustaining voltage gradually increases as the distance becomes smaller than 1 mm. The discharge sustaining voltage when the electron emission region 27 is provided adjacent to the insulating partition 23 is about 70V.

[0014]

Since the present invention is constructed as described above,
Since the amount of cations generated in the discharge space to the insulating partition can be reduced and the charge rate to the cathode surface can be increased, a matrix type gas discharge tube that operates at a relatively low discharge sustaining voltage of about 30 V can be obtained. You can

[Brief description of drawings]

FIG. 1 is a perspective view of a main part of a gas discharge tube embodying the present invention.

FIG. 2 is a perspective view of an essential part of another embodiment of the present invention.

FIG. 3 is a characteristic diagram in which the horizontal axis represents the distance between the electron emission region and the insulating partition of the tunnel effect type electron-emitting device and the vertical axis represents the discharge sustaining voltage.

FIG. 4 is a side sectional view of a conventional gas discharge tube using a tunnel effect type electron-emitting device.

FIG. 5 is a side sectional view of a conventional matrix-type gas discharge tube using a tunnel effect type electron-emitting device.

[Explanation of symbols]

 17 Flat Envelope 18 Rear Glass Plate 19 Cathode 20 Front Glass Plate 21 Anode 22 Discharge Space 23 Insulating Partition 24 Conductor Substrate 25 Dielectric Thin Film 26 Insulating Film 27 Electron Emitting Area

Claims (1)

[Claims] 1. A flat envelope in which gas is enclosed, wherein a large number of strip-shaped cathodes are arranged in one direction on an inner surface of a rear glass plate, and a large number of strip-shaped anodes intersecting with the cathode are provided in front of the flat envelope. Arranged on the inner surface of the glass plate, each anode is separated from other anodes by an elongated insulating partition provided between the anodes,
The cathode is made of a tunnel effect type composed of a conductive substrate and a dielectric thin film covering the surface of the conductive substrate, and its electron emission region is provided at a position avoiding the vicinity of the insulating partition. A gas discharge tube.