KR101938804B1 - Method of assembling and sealing image intensifier - Google Patents

Abstract

The present invention relates to a method for assembling an image amplifier, capable of reducing manufacturing costs by reducing manufacturing processes by assembling, under vacuum conditions, an image amplifier used to improve observation sensitivity of an image in a high sensitivity image sensor for polar light observation such as a night view tool, an ultra-high speed camera, a scintillation camera, and a space telescope camera. The method for assembling an image amplifier according to the present invention comprises: a process of preparing components and materials for cleaning and gas removing; a process of sequentially stacking an output window (where a phosphor screen is formed), a metal ring, a ceramic ring, a metal ring, an MCP, a metal ring, a ceramic ring, and a metal ring, which are components except for an input window (where a photo cathode is formed); a process of inputting a laminate laminated in the laminating process, and the input window into a vacuum chamber; a process of arranging the laminate on a mandrel of the vacuum chamber; a process of arranging the input window on the top of the laminate; a process of pressing the laminate on which the input window is arranged with set pressure; a process of heating the pressed laminate to a first set temperature; a process of reducing the temperature of the heated laminate and releasing the pressure applied to the laminate at a second set temperature; a process of cooling the press-released laminate to the room temperature to obtain an image amplifier, and opening the vacuum chamber; and a process of withdrawing the image amplifier from the vacuum chamber, and testing the same.

Description

METHOD OF ASSEMBLING AND SEALING IMAGE INTENSIFIER [0002]

The present invention relates to a method of assembling an image amplifier, and more particularly, to a method of assembling an image amplifier using an image amplifier capable of reducing a manufacturing cost by assembling an image amplifier used for improving observation sensitivity of a high- As shown in Fig.

Image amplifiers are generally used for improving the observation sensitivity of images in high-sensitivity image sensors for ultra-bright observations, such as night vision equipment, high-speed cameras, flash cameras, and space telescope cameras. Photocells, which emit electrons from photons in a specific energy band, a photocathode, a micro-channel plate (MCP) that amplifies the emitted electrons, and a phosphor screen that converts the amplified electrons back into light.

Japanese Patent Publication No. 2006-522453 relates to an electronic device having a microchannel plate (MCP), and in particular, a method for bonding a microchannel plate to another component is disclosed. This bonding method is a thin film deposition process using a suitable metal selected so as to optimally diffuse the bonding surface at which the microchannel plate and the multilayer ceramic body unit are fitted at an elevated temperature and pressure, wherein the surface vapor deposition layer of the multilayer ceramic body is a microchannel Layer ceramic body unit and a step of forming a protrusion that is arranged to be compatible with the joining of the joining surfaces of the multi-layer ceramic body unit and the plate, A step of positioning the metallized microchannel plate and the multilayer ceramic body unit in a bonding fixture to apply the bonding microchannel plate and the multilayer ceramic body unit to each other; Within the chamber And a step of disposing.

However, such a conventional electronic device having a microchannel plate is a technique for improving the bonding between a microchannel plate and a multilayer ceramic body unit, in which a microchannel plate and a multilayer ceramic body unit are disposed in a bonding fixture, Since the vacuum housing has a step of disposing the vacuum chamber in the vacuum chamber so as to accelerate the diffusion bonding process after the application of the force, the size of the vacuum housing is increased, which is not efficient and the manufacturing cost is increased.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and it is an object of the present invention to provide a method of assembling an image amplifier, which can simplify a manufacturing process and reduce manufacturing cost, .

According to an aspect of the present invention, there is provided a method of assembling an image amplifier, including: preparing components and materials for cleaning and degassing; A process of laminating an output window (in which a phosphor screen is formed), a metal ring, a ceramic ring, a metal ring, an MCP, a metal ring, a ceramic ring, and a metal ring in sequence except for an input window (in which a photocathode is formed) ; A step of injecting the laminated body and the input window in the laminating step into a vacuum chamber; Disposing the laminate on a mandrel of the vacuum chamber; Disposing the input window on an upper portion of the laminate; Pressing the laminate on which the input window is disposed with a set pressure; Heating the pressurized laminate to a first set temperature; Reducing the temperature of the heated laminate and releasing the pressure applied to the laminate at the second set temperature; Cooling the pressure-released laminate to room temperature to obtain an image amplifier and opening the vacuum chamber; And a step of drawing and testing the image amplifier in the vacuum chamber.

In the method of assembling an image amplifier according to the above embodiment, the set pressure applied in the pressing step may be 0.3 kg / mm at the maximum.

In the method of assembling an image amplifier according to the above embodiment, the first set temperature for heating in the heating step is 200 to 350 DEG C, and an induction heater may be used for heating.

In the method of assembling an image amplifier according to the above embodiment, the second set temperature may be 100 to 150 캜.

In the method of assembling an image amplifier according to the above embodiment, the optical gain according to the wavelength of the image amplifier can be measured in the test step.

In the method of assembling an image amplifier according to the above-described embodiment, hemispherical grooves in which indium solder is inserted into the upper and lower surfaces of the ceramic ring may be formed in a ring shape.

In the method of assembling an image amplifier according to the above embodiment, the indium solder may be any one of 52In48Sn, 100In, 90In10Ag and 97In3Ag.

In the method of assembling an image amplifier according to the above embodiment, the ceramic ring bonding surface of the indium solder may be cleaned by a solvent such as an organic solvent or deionized water.

According to the method of assembling an image amplifier according to the embodiment of the present invention, there are provided a step of preparing parts and materials for cleaning and degassing treatment; A process of laminating an output window (in which a phosphor screen is formed), a metal ring, a ceramic ring, a metal ring, an MCP, a metal ring, a ceramic ring, and a metal ring in sequence except for an input window (in which a photocathode is formed) ; A step of injecting the laminated body and the input window in the laminating step into a vacuum chamber; Disposing the laminate on a mandrel of the vacuum chamber; Disposing the input window on an upper portion of the laminate; Pressing the laminate on which the input window is disposed with a set pressure; Heating the pressurized laminate to a first set temperature; Reducing the temperature of the heated laminate and releasing the pressure applied to the laminate at the second set temperature; Cooling the pressure-released laminate to room temperature to obtain an image amplifier and opening the vacuum chamber; And a step of drawing out and testing the image amplifier in the vacuum chamber. That is, the laminated body is disposed in a mandrel in a vacuum chamber, and the input window is stacked to perform most of processes such as pressing, heating, It is possible to reduce the size and efficiency of the vacuum housing. In particular, since the vacuum housing is manufactured in a vacuum state rather than a vacuum state in the conventional technology, the manufacturing process can be shortened and the manufacturing cost can be reduced. It is effective.

1 is an exploded perspective view of components applied to a method of assembling an image amplifier according to an embodiment of the present invention.
2 is a flowchart illustrating a method of assembling an image amplifier according to an embodiment of the present invention.
FIG. 3 is a perspective view of an image amplifier fabricated by the method of assembling the image amplifier of FIG. 2, wherein (a) is an overall view, and FIG. 3 (b) is a detailed view of a portion where a ceramic ring, a metal ring and an MCP are formed.
Fig. 4 shows a plan view (a) of the ceramic ring of Fig. 1 and a cross-sectional view (b) of Fig. 4a taken along line A-A '.
5 is a graph of the durability (Y axis) versus the pressure (X axis) applied during the brazing process at thicknesses of 50 탆 (1), 30 탆 (2) and 20 탆 (3) of the solder alloy.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is an exploded perspective view of parts applied to a method of assembling an image amplifier according to an embodiment of the present invention, FIG. 2 is a flowchart for explaining a method of assembling an image amplifier according to an embodiment of the present invention, 3 is a perspective view of the image amplifier fabricated by the method of assembling the image amplifier of FIG. 2, wherein (a) is an overall view, and (b) is a detailed view of a portion where the ceramic ring, the metal ring and the MCP are formed.

First, components applied to a method of assembling an image amplifier according to an embodiment of the present invention will be described. 1, the image amplifier includes an output window 10 (in which a phosphor screen is formed), a metal ring 20, a ceramic ring 30, a metal ring 20, an MCP 40, a metal A ring 20, a ceramic ring 30, a metal ring 20, and an input window (in which a photocathode is formed) 50 are stacked in this order.

The input window 50 is made of a transparent material having a photo-emitter layer (photocathode) and a conductive coating. The photocathode is responsible for emitting electrons upon receiving light, and determines the energy region of the photons.

The metal ring 20 is made of a conductive material and serves as a contact ring between the photocathode and the phosphor screen and serves as a ring for contacting and holding the MCP 40.

The ceramic ring 30 is made of an insulator and serves to insulate the metal rings 20. Two kinds of ceramics are used for the material of the ceramic ring 30. Specifically, ceramics used are forsterite (Mg ₂ SiO ₃ ) and high-density alumina (Al ₂ O ₃ ). The main parameters of such ceramics are shown in Table 1 below. The accuracy of the ceramic ring 30 is important for the flatness of the ring base and the thickness of the ring. The accuracy of the ceramic ring 30 is 5 to 10 mu m.

Material / parameter Forsterite (F1120) High density alumina (96%) Thermal expansion coefficient, × 10 -6 / K 9.7 7.2 Dielectric strength, kV / mm 17 15 Thermal conductivity, W / m * K 0.78 24

As shown in Figs. 4 (a) and 4 (b), the ceramic ring 30 has hemispherical grooves formed on its upper and lower surfaces in the form of a ring. In this hemispherical groove, indium solder is inserted, and the ceramic ring 30 and the metal ring 20 are bonded to each other by the indium solder that is melted during soldering.

The MCP 40 serves to amplify electrons emitted from the photocathode.

The output window 10 is formed with a phosphor screen for converting electrons amplified by the MCP 40 into light.

The CTE of the input window 50 and the output window 10 and the materials usable for the electrodes is shown in Table 2 below.

Sapphire 5.0 - 5.6 Kobaa 4.5 - 5.2 titanium 8.15 Copper 16.7 Fused silica 0.3 - 0.7 Optical glass K8 7.1

A method of assembling an image amplifier according to an embodiment of the present invention composed of the above-described components will be described.

FIG. 2 is a flowchart for explaining a method of assembling an image amplifier according to an embodiment of the present invention, wherein S means step.

First, components and materials for cleaning and degassing processes are prepared (S10) and the output window 10, the metal ring 20, the ceramic ring 30, the metal ring 20 The MCP 40, the metal ring 20, the ceramic ring 30, and the metal ring 20 are laminated in order (S20).

Subsequently, the laminated body and the input window 50 are put into a vacuum chamber (not shown) in step S20, and a laminate is placed on the mandrel of the vacuum chamber (S40).

The mandrel is installed in the vacuum chamber and has the function of positioning and holding the components in mutually fixed positions and the mechanical pressurization (up to 0.3 kg / mm (~ 0.3 * 107 Pa) according to the command from the outer vacuum chamber , And a function of heating by the induction heater.

Thereafter, the input window 50 is disposed on the upper side of the laminate disposed in the mandrel by the above-mentioned step S40 (S50), and the laminate on which the input window 50 is disposed is set to a set pressure (maximum 0.3 kg / (Step S60). In step S60, the pressurized laminated body is heated to a first set temperature (200 to 350 DEG C). The reason for heating here is for indium soldering.

Unlike RF tubes, indium soldering technology has many advantages, such as simplification of assembly because it does not expect high operating temperature of ICMOS. The soldering of the non-metallic surface can be carried out by the indium-containing solder. Indium wetts materials such as glass, ceramics, mica, quartz and metal oxides. The bond between the solder and the non-metallic surface is due to adhesion to the base metal of the indium oxide layer 800 to 100 Angstroms thick formed in the air. Additional indium oxide is formed during the brazing process in the adhesion zone, thereby bonding the final components. Since the presence of indium oxide is important in the brazing process, the use of flux can not be tolerated. In connection with this fact, it is necessary to thoroughly clean the bonding surface with a suitable solvent such as an organic solvent and deionized water. In the case of solder glass, the adhesion of silica, polished ceramics increases when the surface is preheated to + 350 ° C. The durability of the solder joint obtained is about 0.3 to 0.5 kgf / mm ² . For example, the solder durability of 63Sn37Pb solder is 5 to 7 kgf / mm ² .

 5 is a graph of the durability (Y axis) versus the pressure (X axis) applied during the brazing process at thicknesses of 50 탆 (1), 30 탆 (2) and 20 탆 (3) of the solder alloy. The indium alloys used for soldering are 52In48Sn, 100In, 90In10Ag and 97In3Ag. The first two provide the best wettability, and the third and fourth have excellent durability due to their silver content. In this way, cold indium alloys can be regarded as alternatives to adhesives.

Soldering under pressure can be used to enhance durability and impermeability. This process is as follows: The solder layer (with surface coating form or 20-50 μm foil shape) The surface details are prepared and then heated to the melting temperature of the solder in an oven. A slight pressure (0,3 to 0,5 kgf / mm ² ) can then be applied to the part.

Subsequently, the temperature of the laminated body heated in step S70 is decreased (the temperature is smoothly decreased by 5 to 10 minutes of exposure), and the pressure applied to the laminate at the second set temperature (100 to 150 DEG C) (S80).

In step S90, the pressure-released laminated body is cooled to room temperature by the above-described step S80, an image amplifier is obtained, and the vacuum chamber is opened (S90).

In step S100, the image amplifier is drawn out from the vacuum chamber and tested. In this test, the optical gain according to the wavelength of the image amplifier and the degree of vacuum in the housing of the vacuum chamber are measured.

On the other hand, in the step S20, the components are sequentially stacked outside the vacuum chamber, but the process of laminating the components may be performed in the vacuum chamber instead.

FIG. 3 is a perspective view of an image amplifier fabricated by the method of assembling the image amplifier of FIG. 2, wherein (a) is an overall view, (b) is a view from which an input window and an output window are removed, The details of the portion where the MCP is formed.

According to the method of assembling an image amplifier according to an embodiment of the present invention, a step of preparing parts and materials for cleaning and gas removal processing; A process of laminating an output window (in which a phosphor screen is formed), a metal ring, a ceramic ring, a metal ring, an MCP, a metal ring, a ceramic ring, and a metal ring in sequence except for an input window (in which a photocathode is formed) ; A step of injecting the laminated body and the input window in the laminating step into a vacuum chamber; Disposing the laminate on a mandrel of the vacuum chamber; Disposing the input window on an upper portion of the laminate; Pressing the laminate on which the input window is disposed with a set pressure; Heating the pressurized laminate to a first set temperature; Reducing the temperature of the heated laminate and releasing the pressure applied to the laminate at the second set temperature; Cooling the pressure-released laminate to room temperature to obtain an image amplifier and opening the vacuum chamber; And a step of drawing out and testing the image amplifier in the vacuum chamber. That is, the laminated body is disposed in a mandrel in a vacuum chamber, and the input window is stacked to perform most of processes such as pressing, heating, It is possible to reduce the size and efficiency of the vacuum housing. In particular, since the vacuum housing is manufactured in a vacuum state rather than a vacuum state after the manufacturing in the prior art, the manufacturing process can be shortened and the manufacturing cost can be reduced.

Although the best mode has been shown and described in the drawings and specification, certain terminology has been used for the purpose of describing the embodiments of the invention and is not intended to be limiting or to limit the scope of the invention described in the claims. It is not. Therefore, those skilled in the art will appreciate that various modifications and equivalent embodiments may be made without departing from the scope of the present invention. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

10: Output window
20: metal ring
30: Ceramic ring
30a: hemispherical groove
40: MCP
50: Input window

Claims (8)

A method of assembling an image amplifier used for improving the observation sensitivity of a high sensitivity image sensor for observing an ultra-violet light, comprising:
Preparing components and materials for cleaning and degassing treatment;
A process of laminating an output window (in which a phosphor screen is formed), a metal ring, a ceramic ring, a metal ring, an MCP, a metal ring, a ceramic ring, and a metal ring in sequence except for an input window (in which a photocathode is formed) ;
A step of injecting the laminated body and the input window in the laminating step into a vacuum chamber;
Disposing the laminate on a mandrel of the vacuum chamber;
Disposing the input window on an upper portion of the laminate;
Pressing the laminate on which the input window is disposed with a set pressure;
Heating the pressurized laminate to a first set temperature;
Reducing the temperature of the heated laminate and releasing the pressure applied to the laminate at the second set temperature;
Cooling the pressure-released laminate to room temperature to obtain an image amplifier and opening the vacuum chamber; And
And drawing and testing the image amplifier in the vacuum chamber,
Wherein the optical gain according to the wavelength of the image amplifier is measured in the testing step. The method according to claim 1,
Wherein the set pressure applied in the pressing step is 0.3 kg / mm at maximum. The method according to claim 1,
Wherein the first set temperature for heating in the heating step is 200 to 350 DEG C, and an induction heater is used for heating. The method according to claim 1,
And the second set temperature is 100 to 150 占 폚. delete The method according to claim 1,
Wherein the ceramics ring has a hemispherical groove in which the indium solder is inserted into the upper and lower surfaces in a ring shape. The method according to claim 6,
Wherein the indium solder is one of 52In48Sn, 100In, 90In10Ag and 97In3Ag. The method according to claim 6,
Wherein the bonding surface of the ceramic ring of the indium solder is cleaned by a solvent such as an organic solvent or deionized water.

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