JPH02288133A - Electron beam generating device - Google Patents

Abstract

PURPOSE:To prevent vibration of a linear-shaped cathode electrode by not supporting the cathode electrode in the condition afloat but bearing in the condition in surface contact with a supporting plate. CONSTITUTION:Arrangement according to the present invention includes an electron beam takeout electrode, a back-face base board 5 having a conductive film 7 in a certain shape, a metal base board 2 having an insulation film 3 and provided with a hole 4, No.2 insulation film 6 having a specified thickness to provide a gap between the back-face board 5 and metal board 2, and a linear-shaped cathode electrode 1 which generates an electrode beam. This cathode electrode 1 is brought into contact with the insulation film 3 and stretched. Thus the cathode electrode 1 is prevented from vibration.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an electron beam generating device using a cathode, such as a color television or display for displaying characters or images.

Prior art The first conventional example is, for example, Japanese Patent Application Laid-Open No. 11563/1983.
As shown in Publication No. 2, the structure was as shown in FIGS. 7 and 8.

A striped control electrode 102 is formed on the surface of the insulating substrate 101 using a conductive thin film. Holes 1 are formed in the cathode support member 105 in order to prevent vibrations of the linear cathode electrode 103 that may cause screen disturbances, flickering, etc.
04 are arranged correspondingly on the control electrode 102. Further, the linear cathode electrode 103 is connected to the cathode support member 1
It is stretched in contact with 05. Cathode support member 1
Since 05 requires accuracy, ease of manufacture, insulation, etc., the metal plate 10 has holes 104 formed by etching or the like.
5a may be coated with a heat-resistant insulating material 105b such as alumina, or frit glass may be used.

Further, the structure of the linear cathode electrode 103 and the cathode support member 105 will be explained using FIG. Usually, the linear cathode electrode 103 is a tungsten wire 103 with a diameter of 25 μm.
It has a structure in which an oxide electron emitting material 103b is applied to the surface of a. In order to prevent this oxide electron emitting material 103b from peeling off when it comes into contact with the cathode support member 105, the tungsten wire 10 of the linear cathode 103 must be
3a is exposed, and the exposed portion is required to contact the cathode support member 105. Furthermore, by applying a predetermined potential to an electron beam extraction electrode (not shown), an electron beam can be generated in the direction toward the electron beam extraction electrode.

However, in the first conventional example, it is extremely difficult to expose a portion of the linear cathode quantitatively and accurately.
It is inferior in terms of credibility.

On the other hand, the second conventional example had a structure as shown in FIG. 9, for example. This electron beam generator includes an electron beam extraction electrode 108, a linear cathode 109, a back electrode 1
10, a cathode tension spring 111, and a cathode positioning rib 112. Next, the principle will be briefly explained. After the linear cathode 109 is energized and heated by a voltage applying means (not shown), a voltage lower than that of the linear cathode 109 is applied to the back electrode 110, and a voltage higher than that of the linear cathode 109 is applied to the electron beam pointing electrode 108. When this is applied, the electron beam moves from the linear cathode 109 toward the extraction electrode 108, and is extracted from the hole in the extraction electrode 108.

Further, in the third conventional example proposed in Japanese Patent Application Laid-Open No. 60-84744, as shown in FIG.
This embodiment differs from the second conventional example in that ribs 113 of an insulating material made of frit or the like are provided at a plurality of locations in the longitudinal direction of the linear cathode 109.

Problems to be Solved by the Invention However, in the second and third conventional examples, the back electrode 11
Ribs 112 and 113 of insulating material made of frits etc. are provided at multiple locations in the longitudinal direction of the linear cathode 109 on 0.
It is extremely difficult to form the ribs 112 and 113 with high precision, and it is equally difficult to prevent the vibration of the cathode 109 that comes into contact with the ribs 112 and 113. In order to obtain more advanced performance, new technology is required. is necessary.

That is, the linear cathode is made of a thin tungsten wire, and as the linear cathode 109 becomes longer as in the second conventional example (see Fig. 9), when it receives a small shock, the linear cathode vibrates and generates an electron beam. When used in a display device or the like, image defects such as uneven brightness occur. To this end, a configuration has been proposed that reduces the vibration of the linear cathode, as in the third conventional example (see FIG. 10).

However, even when such ribs are manufactured by screen printing using frit glass, there are problems in that the height of the ribs varies and that gas is released from the frit glass, deteriorating the linear cathode. Furthermore, it has been difficult to form ribs with high accuracy or increase the height of the ribs by screen printing. It is also possible to carve the substrate by etching, but the depth would be limited, and the optimal manufacturing method for making the ribs had not been found.

Therefore, in the second and third conventional examples, it is difficult to prevent cathode vibration that causes image defects such as uneven brightness.

SUMMARY OF THE INVENTION An object of the present invention is to provide an electron beam generator that overcomes the above-mentioned conventional drawbacks and can prevent cathode vibration.

Means for Solving the Problems In order to achieve the above object, the present invention includes an electron beam extraction electrode, a rear substrate having a conductive film formed in a predetermined shape, a first insulating film formed on the surface layer, and a hole portion formed on the back substrate. and a linear cathode electrode mainly composed of a metal core wire and a metal winding and holding an electron emitting substance, and the electron beam extraction electrode is disposed above the linear cathode electrode, A second insulating film having a predetermined shape is formed so as to intersect with the conductive film of the rear substrate, and the metal substrate is disposed on the second insulating film, and the linear cathode electrode is connected to the first insulating film. It is characterized by being stretched in contact with an insulating film.

It also consists of an electron beam extraction electrode, a back substrate with a conductive film formed in a predetermined shape, a metal substrate with an insulating film formed on the surface layer of both sides and a hole, a metal core wire, and a metal winding. and a linear cathode electrode holding an electron emitting material, the electron beam extraction electrode is disposed above the linear cathode electrode, the metal substrate is disposed on the conductive film of the rear substrate, and the linear cathode electrode is arranged above the linear cathode electrode. It is characterized in that the cathode electrode is stretched in contact with an insulating film.

Effects The present invention has the above-mentioned configuration, and instead of supporting the linear cathode electrode in a floating state, 1. It can be supported in surface contact with the support plate. Therefore, since the linear cathode electrode does not vibrate, a high quality image can be obtained.

Here, the contact state between the linear cathode electrode consisting of a metal core wire and a metal winding and holding an electron-emitting substance and the surface of the insulating film of the metal substrate is the contact between the part of the metal winding and the surface of the insulating film. This is a point-contact state in which heat transfer from the linear cathode electrode is difficult, and therefore the temperature of the linear cathode electrode can be maintained almost uniformly.

Furthermore, by forming a conductive film in a predetermined shape on the rear substrate, it is possible to control the electron beam with a simple configuration.

When an insulating film is formed on both sides of a metal substrate, the gap between the metal substrate and the rear substrate can be kept uniform depending on the thickness of the insulating film. Further, when an insulating film is formed on one side of the metal substrate, the gap between the back substrate and the metal substrate is maintained by the insulating film formed on the back substrate.

Furthermore, since the supporting means for the linear cathode electrode is formed by forming an insulating film on a metal substrate, it is easy to process and a substantially uniform surface of the insulating film can be obtained. Furthermore, if this insulating film is formed with a heat-insulating insulating film such as alumina sprayed film, it will have a heat insulating effect when it comes into contact with the linear cathode electrode, and the linear cathode electrode will reduce the temperature drop due to heat transfer and keep the temperature almost uniform. be able to.

When an insulating film is provided on both sides of the metal substrate, the heat insulating effect of the support means is further increased, and the linear cathode electrode can be kept almost uniformly warm by alleviating the temperature drop due to heat transfer.

EXAMPLE Hereinafter, an example of the present invention will be described based on the drawings.

FIG. 1 is a perspective view showing the main structure of an electron beam generator according to an embodiment of the present invention. In FIG. 1, the electron beam generator includes an electron beam extraction electrode (not shown), a back substrate 5 having a conductive film 7 formed in a predetermined shape, and an insulating film 3, in which a hole 4 is formed. It is composed of a metal substrate 2, a second insulating film 6 having a predetermined thickness to provide a gap between the rear substrate 5 and the metal substrate 2, and a linear cathode electrode 1 that generates an electron beam.

Let me briefly explain the principle. A linear cathode electrode 1 is arranged above the rear substrate 5, and an electron beam extraction electrode (not shown) is further arranged. By passing a current through the linear cathode electrode 1, the linear cathode electrode 1 is heated and emits an electron beam. When a negative pressure is applied to the rear substrate 5 and a positive voltage is applied to the electron beam extraction electrode, the electron beam becomes directional in the direction of the electron beam extraction electrode. Further, the electron beam reaches an anode (not shown) formed of an aluminum evaporated film or the like and emits light upon collision.

Here, the rear substrate 5 may be made of an insulating material such as glass, or may have an insulating film formed on a metal material such as 5US430.42-6 alloy or electromagnetic soft iron. Enamel film, electrostatic powder coating film, etc. are suitable for the insulating material used here. The thickness of the insulating film is approximately 150 μm. The thickness of the insulating film is limited because it has capacitance due to the formation of electrodes.

An electrode made of a conductive film 7 is formed on the glass surface or the insulating film surface. The electrodes are formed with thick film conductive paste by screen printing. The thickness of the thick film conductive paste is approximately 2
It is 5 μm. Furthermore, silver paste is used as the thick film conductive paste. The main reasons for using silver paste are that it does not generate gas in vacuum, has good bonding properties, and can be heated and cured at a relatively low temperature.

The linear cathode electrode 1 is a linear cathode that includes a metal core wire 30 and a metal winding 31 and holds an electron emitting material, as will be described in detail later.

The material of the metal core wire 30 and the metal winding 31 is tungsten or the like.

In the case of this embodiment, the linear cathode electrode 1 is in contact with a metal substrate 2, and the metal substrate 2 has an insulating film 3 and a hole 4 formed therein. The insulating film 3 is formed only on one side of the metal substrate 2 that is in contact with the linear cathode electrode 1. This insulating film 3 is suitably an alumina sprayed film or an electrostatic powder coating film. It has good heat resistance, has a film thickness of about 50 μm, and has the advantage of not causing dielectric breakdown. The rear substrate 5 of this embodiment is made of glass.

Although not shown in the figure, an electron beam extraction electrode is provided above the linear cathode electrode 1. A second insulating film 6 interposed between the metal substrate 2 and the rear substrate 5 is formed to intersect with the conductive film 7 formed on the rear substrate 5. This second insulating film 6 is made of glass and is formed by screen printing.

The firing temperature is 480 to 500°C, and in order to obtain a film thickness of about 100 μm, it is necessary to repeat printing and firing several times. At this time, the film thickness change is after baking/after drying = 0
．． 6-065.

FIGS. 2 to 4 each show an electron beam generator according to another embodiment of the present invention.

In the embodiment shown in FIG. 2, the rear substrate 8 has an insulating film 10 formed on a metal core 9. This insulating film 10 is suitably an enamel film or an electrostatic powder coating film. Since these insulating films 10 can be fired at a relatively low temperature, the core bar 9 of the rear substrate 8 will not be thermally deformed.

A conductive film 1 made of a thick conductive paste is disposed on this insulating film 10.
Screen print 1. Further, a second insulating film 13 interposed between the metal substrate 2 and the rear substrate 8 is formed to cross the conductive film 11 formed on the rear substrate 8. This second insulating film 13 is made of glass and is formed by screen printing. An insulating film 3 is formed on only one surface of the metal substrate 2 that is in contact with the linear cathode electrode 1 . This insulating film 2 is suitably an alumina sprayed film or an electrostatic powder coating film. These have good heat resistance, a film thickness of about 50 μm, and have the feature that dielectric breakdown does not occur. The metal substrate 2 is placed in contact with the second insulating film 13.

Further, the linear cathode electrode 1 is fixed in contact with an insulating film 10 formed on the metal core 9.

In the case of the embodiment shown in FIG. 3, the linear cathode electrode 1 has a metal substrate 19 which has an insulating film 3 on both sides and has a hole 18 formed therein.
is in contact with This insulating film 3 is suitably an alumina sprayed film or an electrostatic powder coating film. The rear substrate 20 is made of glass.

A conductive film 21 made of thick conductive paste is formed on the rear substrate 20 by screen printing. After forming a conductive film 21 made of thick film conductive paste on the back substrate 20, the metal substrate 2 with the insulating film 3 formed on both sides is fixed to the back substrate 20.

Furthermore, the linear cathode electrode 1 is fixed to the metal substrate 2.

In the embodiment shown in FIG. 4, the linear canned electrode 1 is in contact with a metal substrate 2 having an insulating film 3 on both sides and having a hole 24 formed therein. This insulating film 3 is suitably an alumina sprayed film or an electrostatic powder coating film. The rear substrate 26 has an insulating film 28 formed on a metal core 27. As the insulating film 3 used here, an enamel film or an electrostatic powder coating film is suitable. A conductive film 29 made of thick film conductive paste is formed on the insulating film 3 of the rear substrate 26 by screen printing. After forming a conductive film 29 made of thick film conductive paste on the back substrate 26, the metal substrate 2 with the insulating film 3 formed on both sides is fixed to the back substrate 26. Furthermore, the linear cathode electrode 1 is fixed to the metal substrate 2.

The linear cathode electrode 1 mainly consists of a metal core wire 30 and a metal winding 31, and holds an electron emitting substance 32, as shown in FIGS. 5(a) and 5(b).

The tensile strength of these linear cathode electrodes 1 was approximately 50 mg. When we examined the magnitude of this tension, it was approximately 20 m.
Good results could be obtained in the range from g to 100 mg.

The diameter of the metal core wire 30 is approximately 40 u mz Metal winding wire 3
1 had a diameter of about 10 μm and a pitch of about 70 μm. Furthermore, calcium carbonate was used as the electron emitting material 32. In addition, the diameter of the metal core wire 30 can be changed from about 20 μm to 5 μm.
We investigated cases where the diameter of the metal winding 31 was up to 0 μm and from about 5 μm to 20 μm, and good results were obtained in both cases.

Here, the structure of the metal substrate 2 that contacts the linear cathode electrode 1 will be explained.

6(a), 6(b), and 6(c) show the case of the embodiment of FIG. 1 in which the insulating film 3 is formed on only one side of the metal substrate 2. The states of the hole 4 of the metal substrate 2 are: (a) a state where there is no insulating film 3 on the wall of the hole 4, (b) a state where the insulating film 3 is partially formed on the wall of the hole 4, ( C) A state in which the insulating film 3 is formed on the wall of the hole 4.

In these conditions, (a), (b), and (c) were superior in terms of brightness in that order, but there was almost no difference in the effect on image quality. However, higher-definition electron beam generators require optimal designs for these holes. Similarly, in each of the embodiments shown in FIGS. 2 to 4, the emission of the electron beam can be stabilized by applying a potential to the metal substrate 2 on which the insulating film 3 is formed.

According to the embodiments described above, the electron beam can be controlled with a simple configuration, vibration of the cathode can be prevented, heat retention is good due to the heat insulation effect, and electrical insulation is good.

Effects of the Invention As described above, according to the present invention, the following effects can be obtained.

(1) Electron beam radiation can be controlled with a simple configuration.

(2) Vibration of the linear cathode electrode can be prevented.

(3) The temperature of the linear cathode electrode can be kept almost constant.

(4) Good electrical insulation between the linear cathode electrode and the back plate can be obtained.

(5) A liquid crystal display device with excellent display quality can be obtained.

(6) A large amount of processing can be performed relatively stably.

[Brief explanation of the drawing]

1, 2, 3, and 4 are perspective views of the main parts of the electron beam generator in each embodiment of the present invention, and FIGS. 5(a) and 5(b) are Front view and cross-sectional view of the linear cathode used, FIGS. 6(a), (b), (c)
1 is a cross-sectional view of each configuration example of the hole portion of the metal substrate used in the embodiment of FIG. 1, FIG. 7 is a partially cutaway perspective view of the electron beam generator in the first conventional example, and FIG. 8 is a partially enlarged view of the electron beam generator. 9 is a sectional view of an electron beam generator according to a second conventional example, and FIG. 10 is a sectional view of an electron beam generator according to a third conventional example. 191. Linear cathode electrode, 2. ,,metal substrate,3. . , insulating film, 4, 18, 24. ,, Hole, 5.8.20
128 , , Rear substrate , 6.13 , , Second insulating film , 7.11.21.29 . , , Conductive film, 9.27. ,
, Metal core, 10.28 , Insulating film, 30 ,
Metal core wire, 3101. Metal winding, 32. ,,electron-emitting material. Name of agent: Patent attorney Shigetaka Kurino

Claims (6)

[Claims] (1) An electron beam extraction electrode, a back substrate having a conductive film formed in a predetermined shape, a metal substrate with a first insulating film formed on the surface layer and a hole, a metal core wire and a metal winding. and a linear cathode electrode that holds an electron emitting material, and the electron beam extraction electrode is disposed above the linear cathode electrode, and is arranged so as to intersect with the conductive film of the rear substrate. A second insulating film having a shape of An electron beam generator. (2) An electron beam extraction electrode, a back substrate with a conductive film formed in a predetermined shape, a metal substrate with an insulating film formed on the surface layer of both sides and a hole, a metal core wire and a metal winding. and a linear cathode electrode that holds an electron emitting material, the electron beam extraction electrode is disposed above the linear cathode electrode, the metal substrate is disposed on the conductive film of the rear substrate, and the wire 1. An electron beam generator characterized in that a shaped cathode electrode is stretched in contact with an insulating film. (3) The metal substrate with an insulating film formed on the surface layer and a hole provided is characterized by being a metal substrate with an insulating film formed on the surface layer and a hole provided with no insulating film on the wall. An electron beam generator according to claim 1 or 2. (4) The metal substrate with an insulating film formed on the surface layer and a hole provided with the hole is characterized by being a metal substrate with an insulating film formed on the surface layer and a hole with a part of the insulating film formed on the wall. The electron beam generator according to claim 1 or 2. (5) A claim characterized in that the metal substrate with an insulating film formed on the surface layer and a hole provided therein is a metal substrate with an insulating film formed on the surface layer and a hole portion with an insulating film formed on the wall. Item 2. Electron beam generator according to item 1 or 2. (6) The electron beam generator according to claim 1 or 2, wherein the metal substrate on which the insulating film is formed and the hole is provided is a metal substrate to which a predetermined potential is applied.