JPH05173047A - Optical fiber material and its production - Google Patents

Abstract

PURPOSE:To obtain an optical fiber easily adaptable for various purposes such as fixing of a metal tube, sealing of the whole fiber, and protecting of a connecting part, etc., by integrating a metal tube with a coated optical fiber with a pressing tool. CONSTITUTION:This fiber material consists of a coated optical fiber 4 coated with a metal film 3 and a thin and long metal tube 5 which is fitted to the coated optical fiber 4. The pressed part of the fiber material has a deformed cross section such as ellipsoid or hexagon over a prescribed width. Thus, the inner circumferential surface of the metal tube 5 and the outer circumferential surface of the metal coating 3 of the coated optical fiber 4 are substantially sealed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical fiber material in which a metal tube is integrated with an optical fiber core wire by using a crimping tool and a method for manufacturing the same, and fixing the metal tube, hermetically sealing the whole or protecting a connection portion. The present invention relates to an optical fiber material that can be easily applied to a wide range, and a manufacturing method thereof.

[0002]

2. Description of the Related Art A thin and flexible optical fiber is coated with UV resin or nylon resin for surface protection. In order to connect the optical fiber to the light emitting element or the light receiving element, a single-core optical fiber from which the resin coating layer has been removed is inserted into a cylindrical ferrule and fixed with an adhesive, or is directly injection-molded with resin. To form an array of light emitting and receiving elements, each fiber of a multi-fiber optical fiber ribbon is inserted into a V-shaped groove of a groove-shaped silicon chip, and the whole is fixed with an adhesive. It is used as it is while being polished and fixed.

In measurement control and physical property measurement inside the vacuum container, analog signals measured by various sensors may be digitally modulated or frequency-modulated and then transmitted to the outside of the container by an optical fiber. Conventionally, an optical fiber transmits a signal from the inside of a vacuum container to the outside through an airtight adapter, and a considerable transmission loss occurs in the airtight adapter.

On the other hand, the optical fiber cores are fusion spliced in which the tip surfaces of the optical fibers are melted at a high temperature at the time of actual use in optical communication or the like, and fixed in a fused state. Before fusion splicing, the plastic coating on the tip of the optical fiber is removed to leave it bare, so it is necessary to reinforce the splicing point after fusion splicing. As a conventional reinforcement method,
After fusion splicing, a heat-shrinkable tube containing a metal wire is fitted and arranged on the connection point, and then the tube is heat-shrinked to integrate the whole, or the same thermoplastic resin as the coating resin is applied at the optical fiber connection point. It is injection molded into a cylinder.

[0005]

Since the adhesive or injection mold used for fixing the optical fiber to the ferrule is an organic material, it has low heat resistance and a large coefficient of thermal expansion, so that the optical axis shifts due to temperature changes. Are likely to occur. Since a groove-shaped silicon chip used for forming an array of light emitting / receiving elements has a predetermined number of V grooves engraved in advance, there is no freedom in the number of optical fibers and the intervals.

For this reason, the inventors of the present invention apply solder plating to the ends of the optical fibers coated with a metal film, arrange a plurality of optical fibers at equal intervals, and then heat the solder plating to fuse the entire core wire array. I'm proposing a way to do it. In this way,
Solder plating has higher heat resistance than adhesives or injection molds that are organic materials, but the heating limit temperature is 150 ° C
In addition to being limited to a certain degree, the process of arranging a plurality of optical fiber core wires plated with solder at equal intervals and then heating and fusing them is complicated.

Further, in measurement control inside the vacuum container, in order to avoid the transmission loss generated in the airtight adapter, the optical fiber core wire may pass through the wall of the vacuum container without passing through the airtight adapter. Since it is extremely fragile, it is impossible to directly penetrate the optical fiber core as much as the plastic coating. Even if the optical fiber core wire is inserted into the metal capillary, the space between the outer circumference of the fiber core wire and the inner circumference of the capillary does not become airtight, and there is a limit in reducing the diameter of the metal capillary by the pipe-making technology.

In use for optical communication or the like, even if a heat shrinkable tube is fitted and fixed at a connection point of a bare optical fiber core wire or a thermoplastic resin is injection-molded into a tubular shape, the connection point is not formed. Is not fully reinforced.
Even with such reinforcement, the fusion spliced optical fiber core is often subject to thermal damage from the splicing point.

The present inventors have studied the characteristics of the quartz optical fiber, and as a result, although the optical fiber is strong against the compressive force in the diametrical direction, the bare optical fiber is liable to have minute scratches, which causes a slight damage. It has been found that it also has the property of being extremely weak against bending. From this property, it is clear that the optical fiber can sufficiently withstand the compressive stress in the uniformly compressed portion, but has a fatal weak point at the boundary a (see FIG. 6) between the compressed portion and the open portion. ..

On the other hand, the optical fiber core wire coated with a metal coating can withstand a higher compression force because the entire circumference is protected by a strong metal coating, and the boundary between the compressed portion and the open portion can be increased. Also in a, sufficient strength is maintained. The present invention utilizes the above-mentioned characteristics of an optical fiber core wire coated with a metal film to fix an optical fiber core wire by a metal tube that is compressed and deformed by pressure bonding, and an optical fiber material having excellent heat resistance and manufacturing thereof. It is intended to provide a way.

Another object of the present invention is to provide a method for manufacturing an optical fiber material, which can easily improve airtightness by fitting a metal tube and then crimping it several times. Another object of the present invention is to provide an inexpensive optical fiber array which has a degree of freedom with respect to the number and intervals of optical fibers. Further, it is also an object to provide a method of protecting a connected optical fiber core wire which maintains the same heat resistance as that of the core wire main body at the connection part of the core wire.

[0012]

In order to achieve the above object, an optical fiber material 1 according to the present invention is an optical fiber in which an optical fiber 2 is coated with a metal coating 3 as shown in FIG. 1 (3). It consists of a core wire 4 and an elongated metal tube 5 which is fitted and arranged with the optical fiber core wire. The metal coating 3 coated on the optical fiber 2 may be directly coated on the optical fiber 2, but normally, the optical fiber 2 is coated with a carbon coating (not shown) and then electroless plating or vacuum deposition is performed. It is preferable to first form a film having a thickness of several .mu.m or less by a method such as electroplating, and then form the film to a predetermined thickness by an electroplating method.

The number of the optical fiber core wires 4 fitted in the metal tube 5 may be one as shown in FIG. 1, two, three (see FIG. 3) or four or more. It is necessary that the inner diameter of the metal tube 5 is as small as possible within a range in which a predetermined number of optical fiber core wires 4 can be inserted, and the metal tube 5 is made of a metal having a high malleability and capable of crimping. Metal tube 5
The material may be selected from gold, silver, tin, copper, lead, etc., for example. In the obtained optical fiber material 1, the crimping portion 6 (FIG. 6) having a predetermined width has an irregular cross section such as an elliptical shape (see FIG. 1) or a hexagonal shape (see FIG. 2) whose upper and lower surfaces are flat,
It is possible to make the inner peripheral surface of the metal tube 5 and the outer peripheral surface of the metal coating 3 of the optical fiber core wire 4 airtight in the crimping portion. It is preferable that the pressure-bonding processed portion 6 has a flat upper and lower surfaces, since it becomes easy to attach it to a substrate (not shown) or the like.

In the optical fiber array (FIG. 4), a plurality of optical fiber core wires 4 are put together in a metal tube 5 as shown in FIG. The lines 4 are arranged at substantially equal intervals. Further, in the optical fiber array (FIG. 5), a plurality of optical fiber core wires 4 are connected to a known groove-shaped silicon chip 10.
The V-shaped grooves 11 may be fitted into the V-shaped grooves 11 and arranged at equal intervals, and the groove-shaped silicon chips may be directly inserted into the metal tube 5 and pressure-bonded. In these optical fiber arrays, the end faces of the respective optical fibers 2 are polished by a conventional method at a predetermined angle such as flat or oblique.

In this optical fiber array, if the end face of each optical fiber 2 is polished to 8 °, a light emitting element 7 such as an LD (FIG. 7), and if the end face is polished to flat or 45 °, PD or APD receives light. It can be used in combination with the element 8 (FIG. 8). When the end face of each optical fiber core is polished to 45 ° as shown in FIG. 8, electrolytic treatment is performed so that the portion near the polished end face of the optical fiber 2 becomes bare. Therefore, 4
After polishing the end face at 5 °, it is necessary to immerse a portion near the polishing end face in an electrolytic solution or a metal solution to remove the tube 5 and the metal film 3 in that portion. At this time, if an electrolytic solution is appropriately selected, the metal film 3 such as nickel can be removed together with the carbon film by an electrolytic reaction, and a metal film such as aluminum can also be removed with an aqueous hydrochloric acid solution.

In the method of the present invention, FIG. 1 (1) to (3)
As shown in the order of steps, the optical fiber core wire 4 is inserted into the metal tube 5, and then the metal tube 5 is compressed and deformed over a predetermined width from the outside by a small crimping tool 9 as illustrated in FIG. By pressure bonding, the metal tube is integrated with the optical fiber core wire 4. This integration means fixing the optical fiber core wire 4 by the metal tube 5.

The crimping tool 9 used in the present invention is a small tool similar to a sleeve manual tool for fixing a crimping terminal to an electric wire, and has a recess 1 formed in a vertically movable piece of the crimping tool.
2, 12 (FIG. 2) are formed symmetrically. The side shape and depth of the recesses 12, 12 correspond to the cross-sectional shape and thickness of the pressure-bonding processed portion 6 in the optical fiber material 1. It is preferable to provide notches 12a for allowing a part of the compressed metal tube 5 to escape on both side walls of the upper and lower recesses 12.

In the method of the present invention, when the metal tube 5 is compressed and deformed by a known crimping tool, the metal tube 5 having a certain thickness is compressed and deformed at room temperature. However, voids tend to remain. When such a pinhole of several μm is formed, the inner peripheral surface of the tube and the outer peripheral surface of the metal coating 3 of the optical fiber core wire 4 are not completely airtight.

As shown in FIG. 6, the airtightness of the crimping portion 6 is determined by appropriately pressing the metal tube 5 in the circumferential direction (for example, 90 degrees in the arrow direction in FIG. 6) after the first crimping with the crimping tool 9a. ) It can be increased by shifting it in the lateral direction while rotating and performing the crimping process again with the crimping tool 9b.
At this time, if the two pressure-bonded portions are overlapped with each other by about 1 mm in the axial direction, the inner peripheral surface of the metal tube 5 and the metal coating 3 of the optical fiber core wire 4 are subjected to the multiple pressure-bonding processing.
Sufficient airtightness can be achieved with the outer peripheral surface of the. Such pressure bonding may be performed three times or more as desired.

In the protection method of the present invention, when connecting two optical fiber core wires, as shown in FIG. 9, the metal coating 3 is removed from the tip end portion of the optical fiber core wire 3 by a predetermined width to leave a bare wire. The optical fiber portion 13 of the is exposed. Although the partial removal of the metal coating 3 is generally carried out by dissolution with a strong acid or strong alkaline cyanide solution, an electrolytic bath having a relatively corrosive and less toxic bath composition is used, and the optical fiber core wire 3 is set as an anode. The cathode may be arranged so that the current density at the tip thereof may be high, or the tip of the core wire may be lowered and gradually immersed in an electrolytic bath for removal.

In the bare optical fiber portion 13, its end face 14 is cut smoothly by a known optical fiber cutting device (not shown), and a metal tube 15 is inserted into one of the optical fiber core wires 2. Next, as shown in FIG. 10, both ends 14 and 14 of the optical fiber core wire are fusion-spliced by using a known fusion splicer (not shown) to form the fusion splicer 1.
6 is formed, and then the metal tube 15 is fusion-bonded to the connecting portion 1
Move to the top of 6. The both ends of the metal tube 15 are pressure-bonded with a pressure-bonding tool to be integrated with the connecting optical fiber core, and fixed on the fusion splicing part 16.

[0022]

In the method of the present invention, the metal tube 5 is pressed by the crimping tool 9.
Therefore, the degree of damage to the optical fiber 2 and the fixing of the optical fiber core wire 4 by the metal tube 5 at this time are important. Although these degrees vary depending on the width of the crimping process and the crimping rate, for example, an outer diameter of 400μ
m, an inner diameter of 200 μm, and a copper tube 5 having a diameter of 135 μm and a nickel-coated optical fiber core wire 4
When the above is inserted and pressure-bonded with a pressure-bonding width of 5 mm and a thickness of 200 to 250 μm, the pull-out force of the optical fiber core wire 4 in the pressure-bonding processed portion 6 is 1.5 kg or more, and fiber deterioration in that portion is not particularly recognized.

In the method of the present invention, as shown in FIG. 1 (1) to (3) in the order of steps, one optical fiber core wire 4
When is inserted into the metal tube 5 and pressure-bonded, the optical fiber core wire 4 is not displaced in the compressed and deformed metal tube 5, and the core wire is always located at the center.
If the two optical fiber core wires 4 are fitted at the same time, the optical fiber core wires 4 are attached to both ends of the inner peripheral surface of the metal tube 5 which is compressed and deformed.
Will be located. Further, as shown in FIG. 3, even if three optical fiber core wires 4 are simultaneously inserted, the arrangement reproducibility is relatively good, and the positions in the case of one and two optical fiber core wires 4, that is, the optical fiber core wires 4 are inserted.
Are located at the center of the metal tube 5 and at both ends of its inner peripheral surface (see FIG. 4).

However, if the four or more optical fiber core wires 4 are inserted into the metal tube 5 at the same time, the arrangement is not reproducible, and a certain regularity cannot be found in the arrangement. Although not shown, in the case of inserting four or more optical fiber core wires, a round tube into which the optical fiber core wires are inserted is processed into a flat shape in advance, or the optical fiber core wires 4 are aligned from the beginning by using a square tube. After the insertion, the array is reproducible by crimping.

Ideally, as shown in FIG. 5, after inserting each optical fiber core wire 4 into the V groove 11 of the groove-shaped silicon chip 10, it has an inner diameter larger than that of the groove-shaped silicon chip. It is preferable to insert it into the elongated metal tube 5 and press-bond it all together. . In this case, the inner peripheral surface of the metal tube 5 and the metal coating 3 of each optical fiber core 2 and the outer peripheral surface of the groove-shaped silicon chip 10 are hermetically sealed in the crimping portion 6, and each optical fiber core 2 Align correctly and evenly.

In order to measure the inside of various vacuum containers with the optical fiber material 1, in order to make airtight so that air leakage does not occur when the container wall is penetrated, after the first pressure bonding process, the pressure bonding process is performed. The crimping process may be performed again while the portions 6 are appropriately overlapped. Sufficient airtightness can be achieved by a plurality of pressure bonding processes, and the airtightness of the optical fiber material 1 is improved to about 10 ⁻⁹ cc / sec · atm.

According to the present invention, in order to measure the transmission loss of the optical fiber 2 in the crimping section 6, the metal tube 5 is provided at the center of the optical fiber core wire 4 connected to the light emitting / receiving element.
Is fitted, and a compressive stress is applied to the metal tube 5 by the crimping tool 9 while continuously monitoring. As a result, the transmission loss of the optical fiber 2 increases by 0 to 0.3 dB, but if the load by the crimping tool 9 is removed after the completion of the crimping, the transmission loss is only 0.01 dB or less, which can be practically ignored.

[0028]

EXAMPLES Next, the present invention will be explained based on examples. Example 1 A single-mode optical fiber 2 having an outer diameter of 125 μm and a wavelength of 1.3 μm is thinly coated with a carbon coating and a base metal coating, and then a nickel coating 3 having a thickness of 5 μm is coated. The outer diameter of 4 is 135 μm. This optical fiber core wire 4 has an inner diameter of 150 μm and an outer diameter of 4
After being inserted into the copper tube 5 of 00 μm, a small crimping tool having a depth of both recesses of 220 μm is used to perform crimping over the axial width 5 mm of the end face portion of the copper tube 5.

As a result of subjecting the optical fiber material 1 obtained by this crimping process to a tensile test, the maximum is 2.66 k when n = 10.
g, min: 1.80 kg, average: 2.33 kg.

Example 2 When a nickel film 3 having a thickness of 5 μm is coated on a multimode optical fiber having an outer diameter of 140 μm and a core diameter of 100 μm, the outer diameter of the optical fiber core wire 4 is 150 μm.
This optical fiber core wire 4 has an inner diameter of 180 μm and an outer diameter of 500
After gradually inserting into the copper tube 5 having a length of 50 μm and a length of 50 mm, a small crimping tool 9a (FIG. 6) having a depth of both recesses of 250 μm is used to perform crimping over a width of 5 mm in the axial direction of the copper tube 5. Next, the copper tube 5 is rotated by 90 degrees in the circumferential direction and displaced by 4 mm in the lateral direction, and the crimping tool 9b having a depth of both recesses of 250 μm is crimped over the axial width of 5 mm. The same crimping process is further performed once, and a total of 3 crimping processes are performed.

As a result, in the copper tube 5, the entire length of the pressure-bonding processed portion 6 is 13 mm (first time: 5 mm, 2
(4th time: 4 mm, 3rd time: 4 mm), and the double pressure-bonding portion has a length of 2 mm. In order to measure the airtightness of the obtained sample, the cylindrical portion of the unpressed portion is fixed to the flange for the airtightness test with silver solder, and a helium leak test is performed.
The leak amount was about 10 ⁻⁹ cc / sec · atm, and the airtightness was greatly improved. This optical fiber material does not cause air leakage even if it penetrates the container wall for measurement inside various vacuum containers, and only one optical fiber is used from the inside of the vacuum container to the outside without an airtight adapter. Can be transmitted directly.

Example 3 When a nickel film 3 having a thickness of 5 μm is coated on a multimode optical fiber having an outer diameter of 125 μm and a core diameter of 50 μm, the outer diameter of the optical fiber core wire 4 is 135 μm. As shown in FIG. 3, the inner diameter of the three optical fibers is 300.
Copper tube 5 μm, outer diameter 800 μm and length 30 mm
After the insertion, the crimping process is performed over the axial width 10 mm of the copper tube 5 using a small crimping tool 19 in which the depths of the recesses 18, 18 are 500 μm.

The end face of the obtained optical fiber array 20 (FIG. 4) is polished and the alignment state of each optical fiber 2 is examined. As a result, as shown in FIG.
The books are aligned and the spacing between the optical fibers 2 is about 50 μm.

Example 4 Using the optical fiber core wire manufactured in Example 3, two optical fiber core wires are inserted into a copper tube in the same manner as in Example 3 and press-bonded, and then the end faces are polished. In the obtained optical fiber material, the optical fiber core wires are located at both ends of the inner peripheral surface of the compressed and deformed copper tube, respectively, and their alignment is good.

This optical fiber material is effective when used as a head for detecting reflected light of a test object by connecting an LD to one optical fiber and a PD to the other optical fiber in a sensor, for example. When this optical fiber material is used for a rotary encoder or the like, the head can be downsized and the heat resistance of the head is excellent.

Example 5 As an optical fiber core wire 4 to be used, a nickel coating 3 having a thickness of 2.5 μm is formed on a single mode optical fiber (cladding diameter 125 μm) 2 for a wavelength of 1.3 μm having a core diameter of 10 μm. To coat. After cutting the fiber core wire 4 to a length of 1 m, the five optical fiber core wires 4 are cut to a length of 30 m.
After inserting into a copper tube processed to have a flat shape of mm, a crimping tool is used to perform crimping over the axial width of 10 mm of the copper tube. Next, the end surface of this optical fiber array is polished so as to form an angle of 8 ° with respect to the flat surface.

The obtained optical fiber array 21 is used for coupling with a light emitting element 7 such as an LD as illustrated in FIG. If the incident end of the optical fiber 2 is not polished to an angle of 8 °, the light from the light emitting element 7 is reflected by the optical fiber 2 and returns to the element to damage the light emitting element 7, or to cause a reflection surface of the light emitting element 7. A resonator is formed at the incident end of the optical fiber 2 to generate noise. Also, with an optical connector used in the middle of the transmission path,
If flat polishing is performed, the light returns to the light-emitting element 7 due to far-end reflection, so it is desirable to polish the end face of the optical fiber 2 to an angle of 8 °.

Example 6 As in Example 5, the optical fiber core wire 4 was used for pressure bonding, and then the end face of the core wire array was polished to form an angle of 45 °. After polishing the end faces, the optical fiber array 22 (FIG. 8)
2 mm near the polishing end surface at the tip of the
Only 3 is immersed in a solution containing 0.1 mol / l KCl. Then, the nickel coating 3 in the vicinity portion 23 is electrolytically removed by electrolysis using the optical fiber array 22 as an anode. As a result of entering light into the optical fiber array 22 as shown in FIG. 8, it is possible to confirm outgoing light that is perpendicular to the axial direction in any of the parallel optical fibers 2.

The optical fiber array 22 is used for coupling with the light receiving element 8 such as PD or APD as shown in FIG.
In the optical fiber array 22, the optical signal 24 passing through the optical fiber 2 can be bent at a right angle and made incident on the light receiving element 8. The optical fiber array 22 can be installed parallel to the substrate on which the light receiving element 8 is mounted, and the installation area can be saved as compared with the flat-polished optical fiber. Example 7 An optical fiber core wire 25 shown in FIG. 9 is made of a GI type silica optical fiber having a core diameter of 50 μm and a cladding diameter of 125 μm,
When this is coated with a nickel film having a thickness of 5 μm, the outer diameter becomes 135 μm. 3 cm of the tip of the optical fiber 25
Is dipped in aqua regia of hydrochloric acid 3: nitric acid 1 and the nickel film on this portion is removed, whereby the optical fiber portion 13 having a bare tip is formed. Two optical fiber core wires 25 are prepared, and at a position 7 mm from the end of the fiber portion 13,
The smooth end face 14 is cut by a known optical fiber cutting device.
To get One optical fiber 25 has an inner diameter of 150μ
m, outer diameter 400 μm and length 20 mm copper tube 15
After inserting the optical fiber, the optical fiber core wires
Both end faces 14 of 5 are fusion-spliced.

When the fusion splicing is completed, the copper tube 15
The center of the is moved so as to be located above the fusion splicing portion 16 (see FIG. 10). The center of the copper tube 15 is the fusion splicing part 1
6, the both ends of the copper tube 15 are crimped with a suitable small crimping tool at a position 1.5 mm from the end face, and the tube 15 is crimped at the crimping portions 26, 26.
To fix.

For the fire resistance test of the optical fiber, the inner diameter of the optical fiber core wires 25, 25 including the fusion splicing portion 16 was set to 0.
Insert into a stainless steel pipe (not shown) with a diameter of 8 mm and an outer diameter of 1.2 mm. After setting the fusion splicing portion 16 to be located at the center, a predetermined fire resistance test is performed. As a result,
The 30 minute fire resistance test passes without an increase in transmission loss. After the test, when the optical fiber core wires 25, 25 are pulled out from the stainless pipe, the copper tube 15 has no particular abnormality and remains in the initial position.

[0042]

The optical fiber material of the present invention is obtained by coating the optical fiber with a metal film, covering it with a metal tube, and integrating it by pressure bonding, without using an organic adhesive or solder having low thermal stability. Therefore, it has sufficient heat resistance and mechanical strength, and is suitable as a heat and fire resistant material. Since this optical fiber material has a small coefficient of thermal expansion, it does not cause misalignment of the optical axis due to temperature changes, the metal tube is hardly oxidized even under severe conditions in fire and heat resistance tests, and the mechanical strength of the optical fiber deteriorates. There is no risk of breakage.

Since the optical fiber material of the present invention has improved airtightness of about 10 ⁻⁹ cc / sec · atm, air leakage does not occur even if it penetrates the container wall for measurement in various vacuum containers. Does not occur. When the optical fiber material of the present invention is used, it is possible to directly transmit from the inside of the vacuum container to the outside with only one optical fiber without using an airtight adapter, and transmission loss at that time can be completely avoided.

In the optical fiber material of the present invention, if the cross-section of the pressure-bonded processed portion over a predetermined width is a polygon such as a hexagon, the position adjustment becomes easy at the time of axial alignment with the light emitting / receiving element. In addition, an optical fiber material having two optical fiber cores has L
It is effective to connect D and PD to the other optical fiber and use it as a head for detecting the reflected light of the test object.
It may be used as a rotary encoder.

Since the optical fiber array of the present invention can align a plurality of optical fiber core wires at equal intervals only by crimping a metal tube, the number and intervals of optical fibers can be relatively freely selected and manufactured. The cost is low. Moreover, in the present invention, since the end portion of the optical fiber core wire row is covered with the metal tube and then the end face of the optical fiber core wire is polished, it is easy to accurately grind the thick metal tube to a predetermined angle. is there.

In the protection method of the present invention, in the optical fiber core wire, the bare optical fiber portion of which the mechanical strength is lowered is reinforced by the metal tube, and the optical fiber core wire is fixed by the metal tube by crimping. In the method of the present invention, since the optical fiber core wire coated with the metal film is used, the bare optical fiber part whose mechanical strength is reduced is reinforced by the metal tube, so that the whole core wire including the connection point is excellent. It has excellent heat resistance and fire resistance.

[Brief description of drawings]

FIG. 1 shows the optical fiber material of the present invention (1) to (3)
FIG. 6 is an enlarged cross-sectional view showing the manufacturing process order in FIG.

FIG. 2 is a cross-sectional view showing a modified example of an optical fiber material and a state in which a crimping tool used for manufacturing the material is opened.

FIG. 3 is an enlarged cross-sectional view showing three optical fiber core wires and a metal tube before manufacturing an optical fiber material.

FIG. 4 is a cross-sectional view showing another modification of the optical fiber material and a crimping tool used for manufacturing the material.

FIG. 5 is a cross-sectional view showing still another modified example of the optical fiber material.

FIG. 6 is a vertical sectional view showing a two-step pressure bonding step in the method of the present invention.

FIG. 7 is a schematic vertical sectional view showing a state in which the optical fiber array of the present invention is combined with a light emitting element.

FIG. 8 is a schematic vertical sectional view showing a state in which the optical fiber array of the present invention is combined with a light receiving element.

FIG. 9 is a partial side view showing a structure of a connecting portion of an optical fiber core wire used in the method of the present invention.

10 is a vertical cross-sectional view showing a state in which the optical fiber core wires of FIG. 9 are connected and integrated by a metal tube.

[Explanation of symbols]

 1 Optical fiber material 2 Optical fiber 3 Metal coating 4 Optical fiber core wire 5 Metal tube 6 Crimping part 9 Crimping tool 10 Groove-shaped silicon chip 12 Cavity tool recess

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshiaki Kurobane 2-5, Kusunekita-machi, Neyagawa-shi, Osaka Kyowa Electric Wire Co., Ltd.

Claims (6)

[Claims] 1. An optical fiber core wire coated with a metal film and an elongated metal tube fitted and arranged with the optical fiber core wire, and a crimping portion having a predetermined width has an irregular cross section such as an ellipse or a hexagon. Then, the optical fiber material in which the inner peripheral surface of the metal tube and the outer peripheral surface of the metal coating of the optical fiber core are airtight in the crimping portion. 2. An optical fiber core wire coated with a metal coating, and an elongated metal tube into which a plurality of optical fiber core wires are fitted together and arranged. A plurality of optical fiber core wires are formed in a crimping portion having a predetermined width. Are arranged at substantially equal intervals, and the inner peripheral surface of the metal tube and the outer peripheral surface of the metal coating of each optical fiber core are airtight in the crimping portion,
Furthermore, an optical fiber array in which the end face of each optical fiber is polished to a predetermined angle. 3. An optical fiber core coated with a metal film, a groove-shaped silicon chip having a plurality of V grooves, and an elongated metal tube having an inner diameter larger than that of the groove-shaped silicon chip. The optical fiber core wires are fitted into the V-grooves of the groove-shaped silicon chip and arranged at equal intervals, and the optical fiber core wires are inserted into the metal tube while the groove-shaped silicon chips are fitted, and the An optical fiber array in which the inner peripheral surface of the tube, the metal coating of each optical fiber core, and the outer peripheral surface of the groove-shaped silicon chip are hermetically sealed, and the end surface of each optical fiber is polished to a predetermined angle. 4. An optical fiber core wire having a metal coating is fitted into an elongated metal tube having high ductility, and then the metal tube is compression-deformed from the outside by a crimping tool over a predetermined width to carry out crimping work. A method for manufacturing an optical fiber material in which a tube is integrated with an optical fiber core wire. 5. An optical fiber core wire having a metal coating is fitted into an elongated metal tube having high ductility, and then the metal tube is crimped over a predetermined width from the outside by a crimping tool, and then the metal tube is circled. A method of manufacturing an optical fiber material, wherein a metal tube is hermetically integrated with an optical fiber core wire by appropriately rotating in the circumferential direction and shifting in the lateral direction to perform crimping again, and overlapping the crimping over a predetermined width. 6. An elongated metal tube is inserted into one of the optical fiber cores, and at the two optical fiber cores, the metal coatings at the tips of the respective optical fiber cores are removed and cut smoothly, and then both ends are fusion-spliced. Then, move the metal tube over the fusion splicing part, and then crimp both ends of the metal tube over the specified width from the outside with a crimping tool to integrate the metal tube with the connecting optical fiber core wire. How to protect the material.