JPH10208689A - Electron tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electron tube having good airtightness and suitable for mass production. SOLUTION: In this electron tube 1, indium 23 stuck to the peripheral wall of the inner wall of a metal support 24 for sealing is interposed between a container 10 and an input face plate 21. The input face plate 21 is pressed against a container 21. Where, a first and a second protrusion parts 71, 72 formed at the end of the container 10 deform the indium 23. Indium 23 pushed out by deformation is pushed into a metal-housing recessed part 73 for sealing provided between the first protrusion part 71 and the second protrusion part 72. Therefore, deformation afforded to the indium 23 surely press-fits indium 23 to the wall faces of the first and the second protrusion part 71, 72 and simultaneously, securely press-fits indium 23 to the wall face of the metal-housing recessed part 73 for sealing as well. The indium 23 positively assures sealing between the input face plate 21 and the container 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electron tube in which a container and an input face plate are bonded and fixed by a sealing metal (for example, a metal mainly containing indium) maintained at a temperature lower than a melting point (for example, normal temperature). It is about.

[0002]

2. Description of the Related Art As a conventional electron tube, there is Japanese Patent Application Laid-Open No. 4-58444. The electron tubes disclosed in these publications are manufactured by the cold indium method. This cold indium method means that when a container and an input face plate are connected via an indium in a vacuum device called a transfer device, the indium is maintained at a temperature lower than a melting point (for example, normal temperature), and the indium remains solid. The technology used in Therefore, when joining the container and the input face plate, the indium is deformed by pressing the input face plate against the container, and the indium is pressed against the container and the input face plate, thereby achieving the vacuum tight sealing of the electron tube. Examples of applying the cold indium method to electron tubes are disclosed in JP-A-57-136748, JP-A-54-16167 and JP-A-61-2194.
No. 1 publication.

As examples of applying the hot indium method to an electron tube, there are JP-A-6-318439 and JP-A-3-133037. The hot indium method is a technique in which a container and an input face plate are joined by indium melted by a heater in a transfer device.In the container side, there is an indium accumulation recess for preventing the molten indium from flowing out. Is provided.

[0004]

However, the electron tube to which the above-described cold indium method is applied has the following problems because it is configured as described above. That is, the end surface of the container and the inner surface of the input face plate are:
Since both are formed as substantially flat surfaces, even if the input face plate and the container are strongly pressed against indium, they have poor conformability at the contact surface with indium, and as a result, sufficient vacuum tightness is required. In some cases, poor airtightness occurred in the electron tube. Then, due to the poor airtightness, oxygen and moisture in the air enter into the electron tube, causing deterioration of the photocathode sensitivity. In particular, when the joining end of the container is formed of a metal material, the compatibility with indium is deteriorated.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide an electron tube having good airtightness and suitable for mass production.

[0006]

According to a first aspect of the present invention, there is provided an electron tube comprising: a container having a first opening and a second opening opposite to the first opening; An input faceplate provided on the opening side and having a photocathode that emits electrons in response to incident light, and an input faceplate provided on the second opening side of the container;
With the input face plate and a stem that defines a vacuum area, the input face plate and the end of the container are opposed to each other, and the space between the input face plate and the end of the container is sealed with pressurized and deformable sealing metal, In an electron tube in which the portion sealed with the sealing metal is surrounded from the outside with an annular sealing metal support, at the end of the container, a sealing metal deformation portion for deforming the sealing metal is formed, The metal deformation portion for sealing includes an annular first protrusion protruding toward the input face plate and positioned inside the end portion, and an annular second protrusion protruding toward the input face plate and positioned outside the end portion. And an annular sealing metal housing recess provided between the first projection and the second projection.

In this electron tube, when the container and the input face plate are joined with a sealing metal (for example, indium or an indium alloy) which can be deformed under pressure, the container is bonded to the inner peripheral surface of the sealing metal support. The sealing metal is placed between the container and the input face plate, and the input face plate is pressed against the container. At this time, the first protrusion and the second protrusion formed at the end of the container deform the sealing metal, and the sealing metal extruded by this deformation is combined with the first protrusion and the first protrusion. 2
Is pushed into the sealing metal housing recess provided between the projections. Therefore, due to such deformation of the sealing metal, the sealing metal is securely pressed against the wall surfaces of the first and second projections, and at the same time, the sealing metal is also formed on the wall surface of the sealing metal housing recess. The metal is securely pressed, and the space between the input face plate and the end of the container can be reliably sealed with the sealing metal. Further, when the sealing metal is deformed under pressure, the annular first protrusion located inside the end of the container appropriately prevents the sealing metal from flowing into the container more than necessary. In addition, the annular sealing metal support located on the outer periphery of the container can appropriately prevent the sealing metal from protruding outside the container more than necessary. Then, by forming the first and second protrusions and the sealing metal housing concave portion in the sealing metal deformation portion of the container, the surface area of the sealing metal deformation portion increases, which is This is one factor that improves the bonding between the metal for use and the end of the container.

In this case, it is preferable that the first or second protrusion is separately fixed to the end face of the container. When such a configuration is adopted, the shape of the first protrusion and the shape of the second protrusion are easily designed in consideration of the conformability of the sealing metal to the first and second protrusions. It can be changed, and projections of various shapes and materials that cannot be formed by integral molding can be produced at low cost.

It is preferable that the tip end surface of the second projection has an inclined surface that is cut off outward. When such a configuration is adopted, when the metal for sealing is deformed by the second protrusion, the metal for sealing can be reliably brought along the wall surface of the second protrusion, and the second protrusion is formed. The pressure-bonding property of the sealing metal to the wall surface of the metal is improved.

[0010] Further, it is preferable to form an annular cutout for accommodating the metal support for sealing on the outer peripheral wall surface of the container. When such a configuration is adopted, the outer peripheral wall surface of the sealing metal support and the outer peripheral wall surface of the container can be substantially flush, and the unevenness of the outer peripheral wall surface of the electron tube can be reduced as much as possible. An electron tube with a simple shape with very little catching becomes possible. Therefore, it is suitable when many electron tubes are arranged densely, and the versatility and handleability of the electron tubes are improved.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of an electron tube according to the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a sectional view showing a first embodiment of an electron tube according to the present invention. As shown in FIG. 1, the electron tube 1 has a cylindrical container 10, and the container 10 is made of various kinds of integral molding methods such as press molding, injection molding, or cutting using Kovar metal having good conductivity. , A ring-shaped bulb 12 made of an electrically insulating material (for example, ceramic), a ring-shaped welding electrode 13 made of Kovar metal, and a bulb 1.
A ring-shaped intermediate electrode 50 made of Kovar metal fixed between the first valve 12A and the second valve 12B formed by dividing 2 into two,
These members 11, 12, 13 and 50 are stacked and arranged concentrically with each other.

The bulb 12 having the intermediate electrode 50
Is provided between the cathode electrode 11 and the welding electrode 13. One end of the bulb 12 is fixed to the flat inner end face 11 a of the cathode electrode 11 by brazing or the like, and the other end of the bulb 12 is After butting against the flat inner end surface 13a of the welding electrode 13, it is fixed by brazing or the like. Further, the bulb 12 is formed by sandwiching the outer peripheral end of the intermediate electrode 50 between the first bulb 12A and the second bulb 12B, and performing a brazing operation on a joint portion. Therefore, the container 10 can be easily integrated by the brazing operation.

Further, the cathode electrode 11, the bulb 12, and the cylindrical main body 13A of the welding electrode 13 are formed to have substantially the same outer shape (in this case, for example, a "circle having a diameter of 14 mm"). Therefore, unevenness can be eliminated from the outer surface of the container 10, and a simple shape free from catching can be obtained. As a result, many electron tubes can be arranged densely even in a narrow space, and an electron tube that is easy to handle becomes possible.
Moreover, a structure that can withstand high pressure is made possible. The outer shapes of the cathode electrode 11, the bulb 12, the intermediate electrode 50, and the welding electrode 13 forming a ring may be polygonal.

The inner peripheral wall surface 11b of the cathode electrode 11 is located inside the inner peripheral wall surface 12a of the bulb 12,
The inside diameter of the cathode electrode 11 is smaller than the inside diameter of the cathode electrode 11. Therefore, it is possible to prevent stray electrons generated at an unintended location on the photoelectric surface 22 side, which will be described later, from colliding with the valve 12, and to charge the valve 12 generated by the collision of the stray electrons and to cause an electron trajectory caused by this. The effect can be eliminated. In this case, since the cathode electrode 11 also serves as the focus electrode of the electron tube 1, when a predetermined voltage is applied to the electron tube 1, electrons emitted from the photoelectric surface 22 having an effective diameter of 8 mm converge to a diameter of about 2 mm. , Semiconductor element 40
Need to be incident on Therefore, the cathode electrode 11
The inner diameter is preferably 10 mm and the length is preferably 3 mm. The first and second valves 12A and 12B made of ceramic have an inner diameter of 11 m.
m and a length of 3 mm are preferred.

The above-mentioned intermediate electrode 50 projects inward from the inner peripheral wall surface 12a of the bulb 12, and the inner diameter of the opening 50a of the intermediate electrode 50 is as small as possible within a range that does not interfere with the electron trajectory (preferably). Is 7 mm). Therefore, the valve 12 is prevented from being charged by stray electrons, and even if the valve 12 is charged for some reason, the electric potential of the space close to the electron trajectory is fixed by the intermediate electrode 50. An adverse effect on the electron orbit can be prevented. The thickness of the intermediate electrode 50 is
0.5 mm is preferred.

A disk-shaped stem 31 made of a conductive material (for example, Kovar metal) is fixed to the welding electrode 13 of the container 10. The stem 31 is connected to the second opening 1 of the container 10.
It is arranged on the 5th side. Here, at the outer end of the cylindrical main body 13A of the welding electrode 13, a circular first flange portion 13B protruding outward for use in joining with the stem 31 is formed, and the inner end of the cylindrical main body 13A is formed. Is formed with a circular second flange portion 13 </ b> C protruding inward for use in joining with the valve 12. Further, a circular notch edge 31a for fitting to the first flange portion 13B is formed on the outer periphery of the stem 31. Therefore, welding electrode 1
3 to the notch edge 3 of the stem 31.
1a, the welding electrode 13 and the stem 31 can be easily joined by a simple assembling operation only by performing resistance welding. During resistance welding, the stem 31
Is very good. Note that a through pin 32 insulated by a glass 34 is fixed to the stem 31.

A semiconductor element 40 operating as an APD (avalanche photodiode) is fixed on the vacuum-side surface of the stem 31 via a conductive adhesive. The diameter of the electron incident surface 44a of the semiconductor element 40 is about 3 mm, and a predetermined portion of the semiconductor element 40 is
It is connected to a through pin 32 insulated from the stem 31 by a wire 33. Further, a plate-shaped anode electrode 60 is disposed between the semiconductor element 40 and the intermediate electrode 50, and an outer peripheral end of the anode electrode 60 is a second electrode of the welding electrode 13.
It is fixed to the flange 13C. The anode electrode 60 is located on the side closer to the semiconductor element 40 and is formed by pressing a stainless steel thin plate having a thickness of 0.3 mm. Note that the distance between the anode electrode 60 and the semiconductor element 40 is preferably 1 mm.

An opening 61 is formed at the center of the anode electrode 60 so as to face the electron incident surface 44a of the semiconductor element 40. This anode electrode 60 has an opening 6
A cylindrical collimator portion (collimator electrode) 62 projecting so as to surround the photoreceptor 1 is integrally formed. The collimator portion 62 protrudes toward the photoelectric surface 22 and is concentric with the opening portion 61. It is arranged in a way. The inner diameter of the collimator section 62 is preferably 3.0 mm, and the height is preferably 1.3 mm. The anode electrode 60 may be formed in advance on an extension of the second flange portion 13C of the welding electrode 13 so that the welding electrode 13 also serves as the anode electrode 60.

As shown in FIG. 2, an input surface plate 21 made of glass for transmitting light is fixed to the cathode electrode 11 of the container 10, and the input surface plate 21 has the photoelectric surface 2 inside.
2 and is disposed on the side of the first opening 14 of the container 10. The input face plate 21 is provided with a photocathode 22
After being manufactured, via a low-melting metal (for example, indium itself, an alloy containing indium as a main component, lead or a lead alloy) which is deformable under pressure and used as a sealing metal (for example, easy to handle and easy to process). As a result, the space between the input face plate 21 and the end of the container 10 is sealed with a low melting point metal 23. The portion sealed with the low melting point metal 23 is surrounded from the outside by an annular sealing metal support 24 made of Kovar metal. Furthermore, the photocathode 2
A photocathode electrode 25 made of a chromium thin film is arranged in a peripheral portion of 2 so as to electrically connect the photocathode 22 and the low melting point metal 23. Inner diameter 8 of this photocathode electrode 25
mm defines the effective diameter of the photoelectric surface 22. In some cases, gold (Au) that can be deformed under pressure is used as the sealing metal.

Here, the cathode electrode 1 in the container 10
At one end, a metal deformation portion 70 for sealing that deforms the low-melting metal 23 is formed. The sealing metal deformation portion 70 includes annular first and second protrusions 71 and 72 protruding toward the input face plate 21, and the first protrusion 71 and the second protrusion 71.
And an annular sealing metal housing recess 73 formed therebetween in cooperation with the projection 72.

The first projection 71 is located inside the end of the container 10 and has a rectangular cross section. The second protrusion 72 is located outside the end of the container 10 and has a triangular cross section. That is, the distal end surface of the second projection 72 is an inclined surface 72a formed so as to be cut off outward. Therefore, by using such an inclined surface 72 a, the low melting point metal 23 can be made to surely follow the wall surface of the second projection 72, and the low melting point metal 23 against the wall surface of the second projection 72. The crimpability is improved. The metal recess 73 for sealing is formed in a U-shape in cross section with the input face plate 21 side open to allow the low melting point metal 23 to be taken in.

Next, a procedure for sealing the space between the container 10 and the input face plate 21 with the low melting point metal 23 in a vacuum device (not shown) called a transfer device will be briefly described. At the time of sealing, the inside of the transfer device is maintained at a temperature lower than the melting point at which the low melting point metal 23 does not melt (for example, normal temperature).

As shown in FIG. 3, the low melting point metal 23 and the input face plate 21 are arranged on the cathode electrode 11 in this order, and are positioned coaxially. In this case, the low melting point metal 23
Is formed into a ring body which is bonded and fixed to the inner peripheral wall surface of the annular metal support 24 for sealing and has a cross section of approximately an isosceles triangle. The low melting point metal 23 has an outer diameter of 13.5 mm, an outer diameter of 14.5 mm, and a height of 2 m.
m is preferred. In this state, when the cathode electrode 11 and the input face plate 21 are pressed against each other at a high pressure of about 150 kg, the low melting point metal 23 is deformed and functions as an adhesive, and the input face plate 21 is integrated with the container 10.

At the time of this integration, the first projection 71 and the second projection 72 formed at the end of the container 10 deform the low-melting metal 23, and the low-melting metal 23 extruded by this deformation is , The first protrusion 71 and the second protrusion 72
Are pushed into the metal receiving recess 73 for sealing provided between them. Therefore, due to such deformation of the low melting point metal 23, the low melting point metal 23 is securely pressed on the wall surfaces of the first and second projections 71 and 72, and at the same time, the wall surface of the sealing metal housing recess 73 is formed. Also, the low-melting-point metal 23 is securely press-bonded, and the space between the input face plate 21 and the end of the container 10 can be reliably sealed with the low-melting-point metal 23, and the airtightness in the electron tube 1 is improved.

Further, when the low melting point metal 23 is deformed under pressure,
An annular first protrusion 7 located inside the end of the container 10
According to 1, it is possible to prevent the low melting point metal 23 from flowing into the container 10 more than necessary, and to prevent the low melting point metal 23 from adhering to the photoelectric surface 22. Also,
An annular sealing metal support 24 located on the outer periphery of the container 10
Accordingly, it is possible to prevent the low melting point metal 23 from protruding from the container 10 more than necessary. Also, the projections 71, 7
2 and the formation of the sealing metal receiving recess 73, the surface area of the sealing metal deformation portion 70 is increased, and the low melting point metal 23 is formed.
And the end of the container 10 are improved, and the airtightness of the electron tube 1 is improved.

The present invention is not limited to the above-described embodiment. For example, as shown in FIG. 4, an outer peripheral wall surface 11c of the cathode electrode 11 in the container 10 is provided with an annular sealing metal support 24. Is formed in an annular cutout portion 74 for accommodating therein. The notch 74 allows the outer peripheral wall 24 a of the sealing metal support 24 and the outer peripheral wall 1
0c can be flush with each other, the unevenness of the outer peripheral wall surface of the electron tube 1 can be reduced as much as possible, and a simple shape with very little catching can be achieved. Therefore, it is suitable when many electron tubes 1 are densely arranged.
The versatility and handleability of the electron tube 1 are improved. That is,
It is possible to meet the demands from the high energy field and medical equipment field in which 1,000 to 10,000 electron tubes 1 are arranged and used in a limited space. Further, as shown in FIG. 5, the second protrusion 75 according to another example does not have an inclined surface at the tip surface, and the tip surface of the second protrusion 75 is the inner surface of the input face plate 21. Are formed in parallel with.

As shown in FIG. 6, a metal deformation portion 80 for sealing according to another embodiment includes first and second annular projections 81 and 82 projecting toward the input face plate 21. It comprises an annular sealing metal housing recess 83 formed between the first projection 81 and the second projection 82 in cooperation with each other. The first projection 81 is located inside the end of the container 10 and has a circular cross section. Furthermore, the first
Is made of nickel, stainless steel, Kovar metal, or the like, and is fixed to the end face of the cathode electrode 11 by resistance welding. As described above, by forming the first protrusion 81 separately from the cathode electrode 11, the first protrusion 81 is formed.
And the cathode electrode 11 can be made of different materials, and the first protrusions 81 of various shapes and materials, which cannot be formed by integral molding, can be made at low cost. In addition, the shape and material of the first protrusion 81 can be easily changed in design in consideration of the conformability of the low melting point metal 23 to the first protrusion 81.

The second projection 82 has a triangular cross section and is formed outside the end of the container 10 and is integrally formed with the cathode electrode 11. That is, the distal end surface of the second projection 82 is an inclined surface 82a formed so as to be cut outward. Therefore, this inclined surface 82
By using a, the low-melting-point metal 23 can be made to surely follow the wall surface of the second projection 82, and the second projection 8
The press-fitting property of the low-melting metal 23 to the second wall surface is improved.
The metal housing recess 83 for sealing has a shape in which the input face plate 21 side is open, so that the low melting point metal 23 can be taken in.

The second projection 82 is connected to the cathode 1
It is also possible to form it separately from one. In this case, the second
The projections 82 and the cathode electrode 11 can be made of different materials, and the second projections 82 of various shapes and materials, which cannot be integrally formed, can be produced at low cost. Further, the low melting point metal 2
The shape and material of the second projection 82 can be easily changed in design in consideration of the conformability of 3. The material of the second protrusion 82 may be stainless steel or the like.

As shown in FIG. 7, the second projection 85 according to another example does not have an inclined surface at the tip end thereof,
Are formed in parallel with the inner surface of the input face plate 21. In this case, the second protrusion 8
5 may be separate from the cathode electrode 11.

[0032]

As described above, the electron tube according to the present invention has the following effects. That is,
At the end of the container, a sealing metal deformation portion for deforming the sealing metal is formed, and the sealing metal deformation portion projects toward the input face plate and has an annular first shape located inside the end portion. , A second annular projection protruding toward the input face plate and positioned outside the end, and an annular sealing member provided between the first projection and the second projection. Since the metal tube has the concave portion, the airtightness of the electron tube is improved. Then, by simply pressing the input face plate against the container with a predetermined pressure, the joining between the input face plate and the container with the sealing metal interposed therebetween is achieved, so that mass production of electron tubes becomes possible.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a first embodiment of an electron tube according to the present invention.

FIG. 2 is an enlarged sectional view showing a main part of the electron tube shown in FIG.

FIG. 3 is an enlarged cross-sectional view of a main part showing an assembly procedure of the electron tube shown in FIG.

FIG. 4 is an enlarged sectional view of a main part of a second embodiment of the electron tube according to the present invention.

FIG. 5 is an enlarged sectional view of a main part showing a third embodiment of the electron tube according to the present invention.

FIG. 6 is an enlarged sectional view of a main part of a fourth embodiment of the electron tube according to the present invention.

FIG. 7 is an enlarged sectional view of a main part showing a fifth embodiment of the electron tube according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Electron tube, 10 ... Container, 10c ... Container outer peripheral wall surface, 1
Reference numeral 2 denotes a second opening, 14 denotes a first opening, 15 denotes a second opening, 21 denotes an input face plate, 22 denotes a photocathode, 23 denotes a low melting point metal (sealing metal), and 24 denotes a metal support for sealing. Body, 31: Stem, 70, 80: Metal deformation portion for sealing, 71, 81: First projection, 72, 75, 82, 85: Second projection,
72a, 82a: inclined surface; 73, 83: recess for accommodating metal for sealing; 74: notch.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroshi Hasegawa 1126-1, Nomachi, Ichinomachi, Hamamatsu City, Shizuoka Prefecture Inside (72) Inventor Shigeru Ichikawa 1126, 1126 Ichinomachi, Hamamatsu City, Shizuoka Prefecture (72) Inventor Hitoshi Kinoshita Hamamatsu Photonics Co., Ltd., 1126, Nomachi, Ichinomachi, Hamamatsu City, Shizuoka Prefecture (72) Inventor Norio Asakura 1, 126-1, Nomachi, Ichinomachi, Hamamatsu City, Shizuoka Prefecture, Japan 72) Inventor Suyama Motohiro 1126 Nomachi, Hamamatsu City, Shizuoka Prefecture, 1 Hamamatsu Photonics Co., Ltd.

Claims (4)

[Claims] A container having a first opening and a second opening located on a side opposite to the first opening; provided on the first opening side of the container, in response to incident light; An input faceplate having a photocathode that emits electrons through the input port; and a stem provided on the second opening side of the container and defining a vacuum region together with the input faceplate, the input faceplate and an end of the container. The input face plate and the end of the container are sealed with a pressure-deformable sealing metal, and a portion sealed with the sealing metal is annularly sealed. In the electron tube surrounded from the outside by a metal support, a sealing metal deformation portion for deforming the sealing metal is formed at the end of the container, and the sealing metal deformation portion is formed by the input face plate. An annular first projection protruding toward the inner side and located inside the end; A second projection of the annular located outside of projecting said end toward the plate,
An electron tube comprising: an annular sealing metal housing recess provided between the first projection and the second projection. 2. The electron tube according to claim 1, wherein the first or second protrusion is separately fixed to an end surface of the container. 3. The electron tube according to claim 1, wherein a tip end surface of the second projection has an inclined surface cut off outward. 4. The electron tube according to claim 1, wherein an annular notch for accommodating the metal support for sealing is formed in an outer peripheral wall surface of the container.