WO2008001449A1 - Fine tube - Google Patents

Abstract

A fine tube (100) reduces connection loss of light. The tube has an outer diameter of 2.5mm or less, and in a status where the end surface of an optical fiber inserted from one end of the fine tube (100) is brought into contact with the end surface of the optical fiber inserted from the other end of the fine tube (100), the two portions inserted into the fine tube (100) of the optical fiber are kept on one straight line. The fine tube is made of ceramics, and a coaxial degree, showing a deviation between the center axis on an outer circumference surface of the fine tube (100) and that within the inner circumference surface of the fine tube (100), is within 3μm.

Description

 Specification

 Fine tube

 Technical field

 [0001] The present invention relates to a microtubule used for connecting optical fibers, for example.

 Background art

 Conventionally, connectors have been used to connect optical fibers. Such a connector includes a ferrule attached to an optical fiber and a connector main body that holds the ferrule. For example, when connecting two optical fibers, attach a ferrule to the tip of each of the two optical fibers to be connected. Then, the end portions to which these ferrules are attached are respectively inserted into the connector bodies, and the end surfaces of the two optical fibers are brought into contact with each other. This connects the two optical fibers.

 However, since such a connector includes the connector main body and the ferrule as described above, the structure is complicated.

 [0004] Thus, in recent years, a microtube used for connecting optical fibers has been proposed (for example, see Patent Document 1).

 [0005] The optical fiber micropipe (connecting sleeve) of Patent Document 1 above has the tip of the optical fiber inserted through the openings at both ends of the micropipe, and the end faces of the two optical fibers are the micropipe. The optical fibers are held so as to face each other at the center. Such a microtube can be simpler in structure than a connector.

 Patent Document 1: Japanese Patent Laid-Open No. 2004-126306

 Disclosure of the invention

 Problems to be solved by the invention

[0006] However, the micropipe described in Patent Document 1 has a problem that the connection loss of light between the optical fibers to be connected increases.

[0007] That is, since the fine tube of Patent Document 1 is made of metal, it is easily deformed by pressure from the surroundings. Furthermore, because it is made of metal, the coefficient of thermal expansion of the microtube is large and its service life is short. As a result, in the micropipe of Patent Document 1 above, pressure and Due to heat, aging, etc., the inserted optical fiber will be misaligned and the optical connection loss will increase.

 [0008] Therefore, the present invention has been made in view of such a problem, and an object of the present invention is to provide a microtube capable of reducing the connection loss of light.

 Means for solving the problem

[0009] In order to achieve the above object, the microtube according to the present invention is configured as a tube having an outer diameter of 2.5 mm or less, and an end face of the optical fiber into which the one end force of the tube is inserted, and the tube A fine tube that keeps the portions of the two optical fibers inserted into the tube in a straight line in contact with the end face of the optical fiber inserted from the other end of the optical fiber. The coaxiality indicating the deviation width between the central axis on the outer peripheral surface of the tube and the central axis on the inner peripheral surface of the microtube is formed so as to be within 3 zm. For example, the microtubule is made of dinoleconium oxide. Alternatively, the microtube is made of aluminum nitride.

 [0010] Thereby, the microtube of the present invention is made of ceramics such as dinenoconium oxide, for example, so that it has excellent heat resistance and is difficult to be deformed as compared with conventional metal microtubes. Because of its small and long service life, it is possible to prevent the occurrence of misalignment, gaps, and other misalignments between the two inserted optical fibers. As a result, optical connection loss can be reduced. Furthermore, in a very small tube with an outer diameter of 2.5 mm or less, the coaxiality is within 3 zm, so that the end faces of two extremely thin optical fibers can be held accurately and reliably in contact with each other. Even in such an optical fiber, the optical connection loss can be reduced and the space can be saved. Also, when such a fine tube is used as a ferrule for an optical fiber, for example, the coaxiality is within 3 / im, so that the end faces of the optical fibers can be brought into contact with each other with high accuracy, and the optical connection Loss can be reduced.

 [0011] Further, at both ends of the fine tube, a recess having an opening having a diameter larger than the diameter of the hole is formed so as to communicate with the hole surrounded by the inner peripheral surface. A little as a feature.

[0012] Thereby, since the opening of the recess communicating with the hole is larger than the diameter of the hole, One end of the optical fiber can be easily inserted into the hole. As a result, the convenience of the microtubule can be improved. Furthermore, if the concave portion into which the optical fiber is inserted is filled with an adhesive made of, for example, a resin material, the optical fiber can be securely fixed.

 [0013] Further, the recess may be formed such that a width of the recess in a direction perpendicular to the depth direction is substantially constant along the depth direction.

[0014] Thereby, the inner surface of the concave portion of the microtube can be brought into contact with the coating material of the optical fiber over a wide area, and the optical fiber inserted into the hole can be reliably held.

[0015] Further, the recess may be formed such that a width of the recess in a direction perpendicular to the depth direction is narrowed toward a deeper direction of the depth.

Accordingly, if one end of the optical fiber is inserted into the recess, the one end is guided to the hole by the recess, so that one end of the optical fiber can be easily inserted into the hole.

[0017] In addition, the microtube may be formed with a slit having an opening on the outer peripheral surface and communicating with the hole.

[0018] Thus, if the slit is inserted, the optical fiber inserted into the hole can be seen, and it can be confirmed whether or not the end faces of the two optical fibers are in contact with each other. Furthermore, if this slit is filled with an adhesive that is a resin material, it can be reliably fixed in a state where the end faces of the two optical fibers are in contact with each other.

[0019] Further, the inner circumferential surface of the microtube is formed with a groove extending from one of the recesses to the other of the recesses.

[0020] Thereby, the air in the hole confined by the insertion into the hole of the optical fiber can escape to the outside of the fine tube through the groove. As a result, the optical fiber can be smoothly inserted into the hole, and the optical fiber can be firmly fixed on the inner peripheral surface.

 [0021] Further, the composite pipe of the present invention comprises the fine pipe as described above and a covering pipe covering the fine pipe, and both ends of the covering pipe protrude from the fine pipe. To do.

[0022] Thereby, the inner surfaces of both ends of the cladding tube can be brought into contact with the coating material of the optical fiber over a wide area, and the optical fiber inserted into the hole can be securely held. If there is a gap between the inner surface of both ends of the cladding tube and the coating material of the optical fiber, the gap If an adhesive made of a resin material is filled in between, the optical fiber can be securely fixed.

 [0023] Here, the optical fiber connection method according to the present invention is an optical fiber connection method for connecting two optical fibers using a micro tube having an outer diameter of 2.5 mm or less, and the micro tube includes: And made of ceramics so that the coaxiality indicating the deviation width between the central axis on the outer peripheral surface of the microtube and the central axis on the inner peripheral surface of the microtube is within 3 μm. In the connection method, for each optical fiber to be connected, the end portion is coupled so that the end surface of the optical fiber is inclined at a predetermined angle with respect to a plane perpendicular to the axial direction at the end portion of the optical fiber. A first insertion step in which one optical fiber processed in the processing step is inserted from one end of the micro tube into a hole surrounded by the inner peripheral surface, and the processing The other optical fiber processed in the process is connected to the other end of the microtube. By inserting al the hole, characterized in that it comprises a second insertion extent E of contacting by opposing end faces of the two optical fibers.

 [0024] As described above, since the micro tube made of ceramics and formed so that the coaxiality is within 3 μΐη is used, the connection loss of light can be reduced as described above. Furthermore, the end of the optical fiber is processed by so-called oblique cutting, and the end face is inclined and elliptical. Therefore, if the end faces of these two optical fibers are brought into contact with each other, the contact is made. The area can be increased, and the optical connection loss can be more reliably reduced.

 [0025] Further, at both ends of the microtube, a recess having an opening having a diameter larger than the diameter of the hole is formed in communication with the hole. In the first insertion step, the one light The covering material that covers the other optical fiber by inserting the one optical fiber into the hole until the covering material that covers the fiber comes into contact with the bottom surface of the recess formed at one end of the microtube. However, the other optical fiber may be inserted into the hole until it contacts the bottom surface of the recess formed at the other end of the microtube.

[0026] With this, if the optical fiber is exposed by peeling off the coating material from one end of the optical fiber covered with the coating material by a length corresponding to, for example, half the length of the hole, the dew The inserted optical fiber is inserted into the hole, and when the end of the covering material is engaged with the bottom surface of the recess, the optical fiber cannot be inserted any further. The surface can be reliably placed in the center of the hole. As a result, the gap between the two end faces can be prevented and the end faces can be reliably brought into contact with each other at the center of the hole.

[0027] It should be noted that the present invention can be realized as such a fine tube for an optical fiber and a connection method as well as a fine tube used for an industrial nozzle, precision equipment, etc. S it can.

 The invention's effect

 [0028] The microtube of the present invention has the effect of reducing the connection loss of light.

 [0029] FIG. 1A is a perspective view of a microtubule according to Embodiment 1 of the present invention.

 FIG. 1B is a front view of the above-mentioned microtube.

 [FIG. 1C] FIG. 1C is a side cross-sectional view of the above-described microtube.

 [FIG. 2] FIG. 2 is an explanatory diagram for explaining the coaxiality of the micropipe of the above.

 [Fig. 3] Fig. 3 is a diagram showing a state in which the above-mentioned microtube connects two optical fiber cables.

 [FIG. 4A] FIG. 4A is a diagram showing end surfaces of the two optical fibers connected to each other.

 [FIG. 4B] FIG. 4B is a diagram showing a state of two optical fibers connected by the microtubules.

 [FIG. 5A] FIG. 5A is a side sectional view of a microtube having a depth of 1.5 mm.

 [FIG. 5B] FIG. 5B is a side cross-sectional view of a microtubule having a slit same as above.

 [FIG. 5C] FIG. 5C is a front sectional view of the above-mentioned microtube.

 [FIG. 5D] FIG. 5D is a side cross-sectional view of a microtube having an outer diameter of 1.25 mm and a diameter of 0.9 mm.

 [FIG. 5E] FIG. 5E is a side cross-sectional view of a microtubule having the same slit.

 [FIG. 5F] FIG. 5F is a side sectional view of a microtube having an outer diameter of 2.5 mm and a diameter of 0.9 mm.

 [FIG. 5G] FIG. 5G is a side sectional view of a microtube having an outer diameter of 2.5 mm, a diameter of 2. Omm, and a slit.

FIG. 6A is a perspective view of a microtubule according to Embodiment 2 of the present invention. [FIG. 6B] FIG. 6B is a front view of the above-mentioned microtube.

 [FIG. 6C] FIG. 6C is a side cross-sectional view of the same microtubule.

 [FIG. 7] FIG. 7 is a view showing a state in which the above-mentioned microtubule connects two optical fiber cables.

 [FIG. 8A] FIG. 8A is a side cross-sectional view of a microtubule having the same slit.

 [FIG. 8B] FIG. 8B is a side sectional view of the microtube having an outer diameter of 1.25 mm.

 [FIG. 8C] FIG. 8C is a side cross-sectional view of a microtubule having the same slit.

 [FIG. 8D] FIG. 8D is a side sectional view of the microtube having an outer diameter of 2.5 mm.

 [FIG. 8E] FIG. 8E is a side cross-sectional view of a microtubule having the same slit.

 FIG. 9A is a side sectional view of a microtubule according to Modification 1 of the above.

 FIG. 9B is a side cross-sectional view of a microtube having a slit according to Modification 1 of the above. 10A] FIG. 10A is a side sectional view of a microtubule according to Modification 2 of the above.

Fig. 10B is a side cross-sectional view of a microtube having a slit according to Modification 2 of the above.

 FIG. 11A is a side cross-sectional view of a microtubule according to Modification 3 of the above.

 FIG. 11B is a side cross-sectional view of a microtube having a slit according to Modification 3 of the above.

 FIG. 11C is a front sectional view of a microtubule according to Modification 4 of the above.

 [FIG. 12A] FIG. 12A is a configuration diagram showing the configuration of the electronic apparatus in the third embodiment of the present invention.

 FIG. 12B is another configuration diagram showing the configuration of the above utility pole device.

FIG. 13 is a diagram showing a current flowing through the core wire same as above.

 FIG. 14 is a diagram showing a process of separating the metal coating from the mold and the core wire.

 FIG. 15 is an explanatory diagram for explaining a state in which the metal film is polished.

FIG. 16 is a flowchart showing a manufacturing method of the microtube according to the above.

FIG. 17 is a configuration diagram showing a configuration of a lighting apparatus according to Modification 1 of the above.

FIG. 18A is a view showing the shape of a molding die according to Modification 2 of the above. FIG. 18B is a view showing another shape of the molding die according to Modification 2 of the above.

 FIG. 18C is a view showing still another shape of the molding die according to the second modification of the above. Explanation of symbols

[0030] 100 microtubules

 120 End face

 120a

 130 Insertion hole

 200 fine tubes

 220 End face

 220a

 230 through hole

 250, 250f, 250g cladding tube

 301, 302

 320 recess

 F1 fiber optic cape

 Fla optical fiber

 Fib coating

 F2 fiber optic cape

 F2a optical fiber

 F2b coating material

 BEST MODE FOR CARRYING OUT THE INVENTION

[0031] Hereinafter, a microtube according to an embodiment of the present invention will be described with reference to the drawings.

[Embodiment 1]

 1A to 1C are diagrams showing the shape of a microtubule according to the first embodiment of the present invention.

FIG. 1A is a perspective view of a microtube, FIG. 1B is a front view of the microtube, and FIG. 1C is a side sectional view of the microtube. [0034] The microtube 100 is made of, for example, zirconium oxide (zircoua) or the like, and is formed in a generally cylindrical shape having a large wall thickness as a whole.

 [0035] A well-shaped recess 120a is formed in a substantially central portion of the two end faces 120 of the microtube 100. Here, the well type is a shape of a hole having the same width in the direction perpendicular to the depth direction at any depth. The bottom surface of the recess 120 a communicates with the through hole 130 of the microtube 100. The through hole 130 is surrounded by the inner peripheral surface of the microtube 100. The length L1 of the microtube 100 is, for example, 0.1 mm to 45 cm, the outer diameter d2 of the microtube 100 is, for example, 0.7 mm, and the diameter of the through hole 130 of the microtube 100 (the inner diameter of the microtube 100). Dl is, for example, 0.05 mm to 2 mm. Further, in the cross section perpendicular to the axial direction of the portion of the microtube 100 where the recess 120a is formed, the shape of the recess 120a is shown as a circle, and the diameter d3 of the circle is, for example, 0.5 mm. The depth L2 is 2 mm, for example.

 Here, microtube 100 in the present embodiment is characterized in that the degree of coaxiality is small. The coaxiality indicates a deviation width between the central axis on the outer peripheral surface of the microtube 100 and the central axis on the inner peripheral surface of the microtube.

 FIG. 2 is an explanatory diagram for explaining the coaxiality of the microtubule 100 in the present embodiment.

 [0038] In microtube 100 in the present embodiment, the center of through-hole 130 (inner periphery r2 in microtube 100) and the microtube 100 The deviation from the center of the outer periphery rl, that is, the coaxiality is within 1 μm. That is, the length variation between the outer periphery rl and the inner periphery r2 is within l x m. Specifically, the variations of the lengths XI, X2,..., X8 between the outer periphery rl and the inner periphery r2 are within l x m. In other words, the relationship Xn_Xm≤l (x m) holds at the two apertures.

[0039] Note that n and m are arbitrary integers of 1 to 8 different from each other. Further, the opening surface is a surface perpendicular to the axial direction of the microtubule 100 and corresponds to a surface including the bottom surface of the recess 120a shown in FIG. 1C. The outer circumference rl is the outer circumference of the microtube 100 in the plane perpendicular to the axial direction of the microtube 100, and the inner circumference r2 is the inner circumference of the microtube 100 in the plane perpendicular to the axial direction of the microtubule 100. It is the circumference of (through hole 130 side). The length between the outer circumference rl and the inner circumference r2 is the distance between the point on the outer circumference rl and the point on the inner circumference r2 that is closest to that point. [0040] Such a micro-tube 100 connects the end faces of these optical fiber cables by inserting the optical fiber cables into the through holes 130 with different directional forces.

 [0041] FIG. 3 is a diagram illustrating a state in which the microtubule 100 connects two optical fiber cables.

 [0042] The optical fiber cable F1 includes an optical fiber Fla having a core and cladding force, and a covering material Fib covering the optical fiber Fla.

 [0043] The end side of such an optical fiber cable F1 is inserted through the recess 120a on one side (left side in FIG. 3) of the microtubule 100 in a state where the coating material Fib is peeled off and the optical fiber Fla is exposed. Inserted into 130. The diameter dl of the insertion hole 130 is smaller than the outer diameter of the portion having the coating material Fib of the optical fiber cable F1 that is larger than the outer diameter of the optical fiber Fla. Therefore, the portion having the coating material Fib on the distal end side of the optical fiber cable F1 is fitted into the recess 120a of the microtube 100 that is not inserted into the through hole 130. That is, in the present embodiment, the optical fiber Fla is inserted into the through hole 130 until the covering material Fib covering the optical fiber Fla comes into contact with the bottom surface of the recess 120a formed at one end of the microtube 100.

 [0044] On the other hand, the optical fiber cable F2 to be connected to the optical fiber cable F1 also has an optical fiber F2a composed of a core and a clad, and a covering material F2b covering the optical fiber F2a, as described above.

 [0045] The end side of such an optical fiber cable F2 passes through the recess 120a on the other side (the right side in FIG. 3) of the microtube 100 in a state where the covering material F2b is peeled off and the optical fiber F2a is exposed. It is inserted into the hole 130. The diameter dl of the through hole 130 is smaller than the outer diameter of the portion of the optical fiber cable F2 having the coating material F2b that is larger than the outer shape of the optical fiber F2a. Therefore, the portion of the optical fiber cable F2 having the coating material F2b on the tip side is fitted into the recess 120a of the microtube 100 that is not inserted into the through hole 130. That is, in the present embodiment, the optical fiber F2a is inserted into the through hole 130 until the covering material F2b covering the optical fiber F2a comes into contact with the bottom surface of the recess 120a formed at one end of the microtube 100. .

As a result, the two optical fiber cables Fl 1 and F 2 are in a state in which the end faces of the respective optical fibers Fla and F 2 a are abutted at the approximate center of the microtube 100. The microtubule 100 is held and fixed in a straight line with the two optical fibers Fla and F2a in contact with each other in this way. Also The two optical fiber cables Fl and F2 are fixed by adhering the inner surface of the recess 120a and the covering materials Fib and F2b with an adhesive made of a resin material. The two optical fiber cables Fl and F2 may be fixed by pressing a wedge or the like between the inner surface of the recess 120a and the covering materials Flb and F2b.

 As described above, in the present embodiment, the coating material is peeled off from one end of the optical fiber covered with the coating material by a length corresponding to, for example, half of the length of the through hole 130 to remove the optical fiber. If it is exposed, the exposed optical fiber is inserted into the through hole 130, and when the end of the covering material engages the bottom surface of the recess 120a, the optical fiber is inserted deeper. Therefore, the end face of the optical fiber can be reliably arranged in the center of the insertion hole 130. As a result, it is possible to prevent the gap between the two end faces from being generated, and to reliably contact the end faces at the center of the insertion hole 130. In this embodiment, since the opening of the recess 120a communicating with the insertion hole 130 is larger than the diameter of the through hole 130, one end of the optical fiber can be easily inserted into the insertion hole 130 via the recess 120a. Can be inserted. As a result, the convenience of the microtube 100 can be improved. Further, in the present embodiment, the recess 120a is formed in a well shape, that is, the width of the recess 120a in the direction perpendicular to the depth direction is substantially constant along the depth direction. Therefore, the inner surface of the recess 120a of the microtube 100 can contact the optical fiber coating material in a wide area, and can securely hold the optical fiber inserted into the through hole 130. be able to. The size of the recess 120a is arbitrarily set according to the size of the optical fiber to be inserted and the holding strength. For example, although the diameter d3 of the recess 120a is 0.5 mm, the depth L2 of the recess 120a is 2 mm. Any size of 5mm or more may be used.

 FIG. 4A is a diagram showing end surfaces of the optical fibers Fla and F2a that are connected to each other.

 [0049] When the optical fibers Fl a and F2a are connected, their ends are processed in advance. In other words, the end face of the optical fiber Fla and the end face of the optical fiber F2a are processed so as to be inclined at the same angle rather than perpendicular to the axial direction. In other words, each end surface is formed in an ellipse rather than a circle.

FIG. 4B is a diagram showing a state of the optical fibers Fla and F2a connected by the microtubule 100. The

 [0051] The end face of the optical fiber Fla and the end face of the optical fiber F2a face each other and are in contact with each other without a gap.

 [0052] Thus, in the present embodiment, the end portions of the optical fibers Fla and F2a are processed by so-called oblique cutting, and the end surfaces are inclined and have an elliptical shape. If the end faces of the fibers Fla and F2a are opposed to each other and contacted without gaps, the contact area can be increased and the optical connection loss can be reduced more reliably.

 [0053] In the above embodiment, the force with the depth L2 of the recess 120a being 2 mm is set to 1.5 mm.

 FIG. 5A is a side cross-sectional view of a microtube having a depth of L2 = 1/5 mm.

 [0055] The microtubule 100a is the above-described microtubule 1 except that the depth L2 of the recess 120a is 1.5 mm.

It is formed to be equal to 00.

[0056] In such a microtube 100a, the depth L2 of the recess 120a is 1.5 mm, and the microtube

Since it is shallower than the depth L2 of the 100 recesses 120a, the optical fiber can be easily passed through the through hole 130 of the microtubule 100a. As a result, the two optical fibers can be easily connected.

 [0057] Further, a slit may be provided in a substantially central portion of the microtube 100a.

FIG. 5B is a side cross-sectional view of a microtube having a slit.

 [0059] The microtube 100b is formed with a slit 140b that has an opening at a substantially central portion of the side surface of the microtube 100b and communicates with the through hole 130. The opening surface of the slit 140b is an elongated, substantially rectangular shape, and the length of the opening surface along the axial direction of the microtube 100b is, for example, approximately lmm. The microtube 100b is formed to be equal to the above-described microtube 100a except that the slit 140b is formed.

 [0060] In such a fine tube 100b, since there is a slit 140b force S, it is possible to visually confirm the state in which the end faces of the two optical fibers are connected.

That is, in inserting the two optical fibers into the through-hole 130 in the microtube 100b, first, while visually observing the inside of the slit 140b, until the end face of one optical fiber appears at the back of the slit 140b. Then, one of the optical fibers is inserted into the insertion hole 130. And slit 140b While observing the inside, the other optical fiber is inserted into the through hole 130 until the end surface of the other optical fiber appears in the back of the slit 140b and contacts the end surface of the one optical fiber described above. As a result, if the slit 140b is viewed, it is possible to see the optical fiber inserted into the through hole 130, and it is confirmed whether the end faces of the two optical fibers are in contact with each other. Is possible. Furthermore, if the slit 140b is filled with an adhesive made of a resin material, it can be reliably fixed in a state where the end faces of the two optical fibers are in contact with each other.

[0062] Further, in the above embodiment, the force S is set such that the outer diameter d2 of the microtube 100 is 0.7 mm and the direct diameter d3 of the recess 120a is 0.5 mm, and the outer diameter d2 is 1.25 mm. The diameter d3 of 120a may be 0.9 mm.

 [0063] FIG. 5C is a front sectional view of the microtubule 100b.

 [0064] As shown in Fig. 5C, the slit 140b has a wide opening on the outer peripheral surface side of the microtube 100b and a narrow opening on the insertion hole 130 side. That is, the width of the slit 140b becomes narrower from the outer peripheral surface side of the microtube 100b toward the insertion hole 130 side.

 FIG. 5D is a side cross-sectional view of a microtube having an outer diameter d2 = l.25 mm and a diameter d3 = 0.9 mm.

 [0066] The microtube 100c is formed to be equal to the microtube 100 described above except that the outer diameter d2 is 1.25 mm and the diameter d3 of the recess 120a is 0.9 mm.

 [0067] In such a microtubule 100c, the diameter d3 of the recess 120a is 0.9 mm, which is longer than the diameter d3 of the recess 120a of the microtube 100. Therefore, a thick optical fiber cable is inserted into the recess 120a. be able to. Furthermore, the outer diameter d2 of the microtubule 100c is larger than the outer diameter d2 of the microtubule 100. The microtubule 100c is thicker than the microtubule 100, so the connection between the two optical fibers is more reliable. Can be protected.

 [0068] Further, a slit may be provided in a substantially central portion of the microtubule 100c.

 FIG. 5E is a side cross-sectional view of a microtubule having a slit.

[0070] The microtube 100d is formed with a slit 140d that has an opening at a substantially central portion of the side surface of the microtube 100d and communicates with the through hole 130. The opening surface of the slit 140d has an elongated and substantially rectangular shape, and the length of the opening surface along the axial direction of the microtube 100d is, for example, approximately 1.5 mm. The microtube 100d is formed to be equal to the microtube 100c described above except that the slit 140d is formed. [0071] In such a microtubule lOOd, since the slit 140d has a force S, it is possible to visually confirm that the end faces of the two optical fibers are connected.

[0072] In the above embodiment, the outer diameter d2 of the microtube 100 is set to 0.7 mm, the direct diameter d3 of the recess 120a is set to 0.5 mm, and the outer diameter d2 is set to 2.5 mm. The diameter d3 may be 0.9 mm.

 FIG. 5F is a side sectional view of a microtube having an outer diameter d2 = 2.5 mm and a diameter d3 = 0.9 mm.

[0074] The microtube lOOe is formed to be equal to the microtube 100 described above except that the outer diameter d2 is 2.5 mm and the diameter d3 of the recess 120a is 0.9 mm.

[0075] In such a microtube lOOe, the diameter d3 of the recess 120a is 0.9 mm,

Since it is longer than the diameter d3 of 100 recesses 120a, a thick optical fiber cable can be inserted into the recess 120a. Furthermore, the outer diameter d2 of the microtube 100e is larger than the outer diameter d2 of the microtubule 100. The microtube 100e is thicker than the microtube 100, so the connection between the two optical fibers is more reliable. Can be protected.

[0076] Further, in the above embodiment, force S is set so that the outer diameter d2 of the microtube 100 is 0.7 mm and the diameter d3 of the recess 120a is 0.5 mm, and the outer diameter d2 is 2.5 mm, and the recess 120a The diameter d3 may be 2 mm. Furthermore, you may provide a slit in the approximate center part of a microtube.

FIG. 5G is a side cross-sectional view of a microtube having an outer diameter d2 = 2.5 mm, a diameter d3 = 2.0 mm, and a slit.

 [0078] The microtube 100f is formed so that the outer diameter d2 is 2.5 mm and the diameter d3 of the recess 120a is 2.0 mm. Further, the microtube 100f is formed with a slit 140f that has an opening at a substantially central portion of the side surface of the microtube 100f and communicates with the through hole 130. The opening surface of the slit 140f is an elongated and substantially rectangular shape, and the length of the opening surface along the axial direction of the microtube 100f is, for example, approximately 2 mm. The fine tube 100f is formed to be equal to the above-described fine tube 100 except for the slit 140f, the outer diameter d2 and the diameter d3.

[0079] In such a micro tube 100f, the diameter d3 of the recess 120a is 2.0 mm, which is longer than the diameter d3 of the micro tube 100, so that a thicker optical fiber cable can be inserted into the recess 120a. . Furthermore, the outer diameter d2 of the microtube 100f is larger than the outer diameter d2 of the microtubule 100. The microtubule 100f is thicker than the microtube 100. It can be surely protected. Furthermore, since the microtube 100f has the slit 140f, it is possible to visually confirm the state in which the end faces of the two optical fibers are connected.

 As described above, in this embodiment, since the microtubule is made of ceramics, it has excellent heat resistance and is difficult to be deformed as compared with a conventional metal microtubule. This can prevent the occurrence of axial misalignment, angular misalignment, and gaps, and as a result, light connection loss can be reduced. Furthermore, since the coaxiality is within 1 / im in a very small tube with an outer diameter of 2.5 mm or less, the end faces of two extremely thin optical fibers can be held accurately and securely in contact with each other. As a result, the optical connection loss can be reduced even for such an optical fiber. Furthermore, space saving can be achieved. In addition, when such a fine tube is used as a ferrule for an optical fiber, for example, since the coaxiality is within lxm, the end surfaces of the optical fibers can be brought into contact with each other with high accuracy, thereby reducing the optical connection loss. can do.

 [0081] (Embodiment 2)

 6A to 6C are diagrams showing the shape of the microtubule in the second embodiment of the present invention.

 FIG. 6A is a perspective view of the microtube, FIG. 6B is a front view of the microtube, and FIG. 6C is a side sectional view of the microtube.

 [0083] The microtube 200 in the present embodiment is made of, for example, zirconium oxide, as in the microtube 100 of the first embodiment, and is formed in a generally cylindrical shape with a large wall thickness. A V-shaped recess 220a is formed in a substantially central portion of the two end faces 220 of the microtube 200 so that the width decreases toward the back. The bottom of the recess 220a communicates with the through hole 230 of the microtube 200. Such a recess 220a is provided to guide one end of the optical fiber to the through hole 230. Therefore, the optical fiber can be easily inserted into the through hole 230 by such a recess 220a.

[0084] The length L1 of the microtube 200 is, for example, 0.1 mm to 45 cm, the outer diameter d2 of the microtube 200 is, for example, 0.7 mm, and the diameter of the through hole 230 of the microtube 200 (fine The inner diameter (dl) of the tube 200 is, for example, 0.05 mm to 2 mm. In such a microtubule 200, optical fibers are inserted into the through holes 230 from different directions, thereby connecting the end faces of these optical fibers and keeping the two optical fibers in a straight line.

 [0086] In addition, microtube 200 in the present embodiment is formed to have a coaxial force lzm or less, like microtube 100 in the first embodiment.

[0087] FIG. 7 is a diagram showing a state in which the microtubule 200 connects two optical fiber cables.

 [0088] The front end side of the optical fiber cable F1 has a through hole from the recess 220a on one side (left side in FIG. 7) of the microtube 200 in a state where the coating material Fib is peeled off and the optical fiber Fl a is exposed. Inserted into 230. The diameter dl of the through hole 230 is smaller than the outer diameter of the portion having the coating material Fib of the optical fiber cable F1 larger than the outer diameter of the optical fiber Fla. Therefore, the portion having the coating material Fib on the distal end side of the optical fiber cable F1 is fitted into the recess 220a of the microtubule 200 without being inserted into the insertion hole 230. In other words, in the present embodiment, the optical fiber Fla is inserted into the insertion hole 230 until the covering material Fib covering the optical fiber Fla contacts the bottom surface of the recess 220a formed at one end of the microtube 200.

 On the other hand, the distal end side of the optical fiber cable F2 is passed through the recess 220a on the other side (right side in FIG. 7) of the microtube 200 in a state where the coating material F2b is peeled off and the optical fiber F2a is exposed. Hole 2 30 is inserted. The diameter dl of the through hole 230 is larger than the outer shape of the optical fiber F2a and smaller than the outer diameter of the portion of the optical fiber cable F2 having the covering material F2b. Therefore, the portion having the coating material F2b on the tip side of the optical fiber cable F2 is fitted into the recess 220a of the microtube 200 that is not inserted into the through hole 230. That is, in the present embodiment, the optical fiber F2a is inserted into the through hole 230 until the covering material F2b covering the optical fiber F2a contacts the bottom surface of the recess 220a formed at one end of the microtube 200. .

As a result, the two optical fiber cables Fl 1 and F 2 are in a state in which the end faces of the optical fibers Fla and F 2 a are abutted at the approximate center of the microtube 200. The microtube 200 is held and fixed in a straight line with the two optical fibers Fla and F2a in contact with each other. In addition, the two optical fiber cables Fl and F2 are fixed by adhering the inner surface of the recess 220a and the covering materials Fib and F2b with an adhesive. Note that the inner surface of the recess 220a and the covering material Fib, F The two optical fiber cables Fl and F2 may be fixed by inserting a wedge or the like between 2b.

 As described above, in this embodiment, as in the first embodiment, the coating is applied from one end of the optical fiber covered with the coating material by a length corresponding to, for example, half the length of the through hole 230. If the optical fiber is exposed by peeling off the material S, when the exposed optical fiber is inserted into the through hole 230 and the end of the covering material is engaged with the bottom surface of the recess 220a, the optical fiber is exposed. The optical fiber can no longer be inserted further, and the end face of the optical fiber can be reliably placed in the center of the through hole 230. As a result, the occurrence of a gap between the two end faces can be prevented, and the end faces can be reliably brought into contact with each other at the center of the through hole 230. In this embodiment, since the opening of the recess 220a communicating with the through hole 230 is larger than the diameter of the through hole 230, one end of the optical fiber can be easily inserted into the insertion hole 230 through the recess 220a. Can be inserted. As a result, the convenience of the fine tube can be improved.

 It should be noted that a slit may be provided in a substantially central portion of the microtube 200.

 FIG. 8A is a side cross-sectional view of a microtube having a slit.

 [0094] The microtube 200a is formed with a slit 240a having an opening at the substantially central portion of the side surface of the microtube 200a and communicating with the through hole 230. The opening surface of the slit 240a is an elongated, substantially rectangular shape, and the length of the opening surface along the axial direction of the microtube 200a is, for example, approximately lmm. The microtube 200a is formed to be equal to the microtube 200 described above except that the slit 240a is formed.

 In such a fine tube 200a, since there is a slit 240a, it is possible to visually confirm the state in which the end faces of the two optical fibers are connected.

 In the above embodiment, the outer diameter d2 of the microtube 200 is set to 0.7 mm, but the outer diameter d2 may be set to 1.25 mm.

 FIG. 8B is a side cross-sectional view of a microtube having an outer diameter d2 = 1.25 mm.

 [0098] The fine yarn field pipe 200b is formed to be equal to the fine pipe 200 described above except that the outer diameter d2 is 1.25 mm.

[0099] In such a micro tube 200b, the outer diameter d2 of the micro tube 200b is larger than the outer diameter d2 of the micro tube 200. Optical fiber The connecting portion can be more reliably protected.

[0100] Further, a slit may be provided in a substantially central portion of the microtube 200b.

[0101] FIG. 8C is a side sectional view of a microtubule having a slit.

 [0102] The microtube 200c is formed with a slit 240c that has an opening at a substantially central portion of the side surface of the microtube 200c and communicates with the through hole 230. The opening surface of the slit 240c is an elongated, substantially rectangular shape, and the length of the opening surface along the axial direction of the microtube 200c is approximately 1.5 mm. The microtube 200c is formed to be equal to the microtube 200b described above except that the slit 240c is formed.

 [0103] In such a fine tube 200c, since there is a slit 240c, it is possible to visually confirm the state in which the end faces of the two optical fibers are connected.

 [0104] In the above embodiment, the outer diameter d2 of the microtube 200 is set to 0.7 mm, but the outer diameter d2 may be set to 2.5 mm.

 FIG. 8D is a side cross-sectional view of a microtube having an outer diameter d2 = 2.5 mm.

 [0106] The microtube 200d is formed to be equal to the microtube 200 described above except that the outer diameter d2 is 2.5 mm.

 [0107] In such a microtube 200d, the outer diameter d2 of the microtube 200d is larger than the outer diameter d2 of the microtube 200. The connecting part of the optical fiber can be protected more reliably.

 [0108] Furthermore, a slit may be provided in a substantially central portion of the microtube 200d.

 FIG. 8E is a side cross-sectional view of a microtube having a slit.

 [0110] The microtube 200e is formed with a slit 240e having an opening at the substantially central portion of the side surface of the microtube 200e and communicating with the through hole 230. The fine yarn field pipe 200e is formed to be equal to the above-described fine pipe 200d except that a slit 240e force is formed.

 [0111] In such a microtube 200e, since there is a slit 240e, it is possible to visually confirm the state in which the end faces of the two optical fibers are connected.

[0112] As described above, in this embodiment, since the microtubule is made of ceramics as in the first embodiment, it has excellent heat resistance and is difficult to be deformed as compared with the conventional metal microtubule. It is possible to prevent the occurrence of axial misalignment, angular misalignment, and gaps between the two inserted optical fibers. As a result, the optical connection loss can be reduced. Furthermore, since the coaxiality is less than 2.5 mm for an extremely small tube with an outer diameter of 2.5 mm or less, the end faces of two extremely thin optical fibers can be held accurately and securely in contact with each other. As a result, the optical connection loss can be reduced even for such an optical fiber. In addition, space can be saved. Also, when such a fine tube is used as an optical fiber ferrule, for example, since the coaxiality is within lzm, the end faces of the optical fibers can be brought into contact with each other with high accuracy, and the optical connection loss can be reduced. Can be reduced.

[0113] (Variation 1)

 The micropipe according to this modification is composed of a micropipe main body and a cladding tube covering the micropipe main body.

 [0114] FIG. 9A is a side sectional view of a microtubule according to this modification.

 [0115] The microtube 201 according to this modification is composed of a microtube body 200f and a cladding tube 250f.

 [0116] The fine tube body 200f is formed so as to be equal to the fine tube 200 of the above embodiment except that the outer diameter d2 is 0.9 mm.

 [0117] The cladding tube 250f is made of a metal such as stainless steel, for example, and is formed so that its inner surface contacts the outer surface of the microtube body 200f and covers the microtube body 200f. Further, the cladding tube 25 Of is formed longer in the axial direction than the fine tube main body 200f.

 [0118] The fine tube main body 200f is inserted into a substantially central portion of the cladding tube 250f, and both ends of the fine tube main body 200f are placed in the cladding tube 250f. That is, both ends of the cladding tube 250f protrude from the fine tube body 200f.

[0119] In the microtube 201 according to this modification, for example, the portion of the optical fiber cable having the coating material is inserted into the concave portion 220a of the microtube main body 200f of the one end force of the cladding tube 250f, and the light of the optical fiber cable. Only the fiber is passed through the through hole 230 of the fine tube body 200f. Also, the optical fiber cable connected to the above-described optical fiber cable is inserted from the other end of the cladding tube 250f in the same manner as described above. As a result, the end faces of the two optical fibers are brought into contact with each other at the approximate center of the fine tube body 200f. Then, the inner surfaces of both ends of the cladding tube 250f and the coating material of the optical fiber cable are fixed by, for example, an adhesive. This connects the two optical fiber cables. The inner surface of both ends of the cladding tube 250f and the coating The two optical fiber cables may be fixed by pushing a wedge or the like between the materials.

 [0120] In such a fine tube 201, since the cladding tube 250f is made of a metal, the cladding tube 250f can be welded or soldered to another metal. Can be easily and reliably fixed to other members.

 [0121] Note that a slit may be provided in a substantially central portion of the microtubule 201.

 FIG. 9B is a side cross-sectional view of a microtube having a slit.

 [0123] The microtube 202 is formed with a slit 270g having an opening at the substantially central portion of the side surface of the microtube 202 and communicating with the through hole 230. The microtube 202 is formed to be equal to the microtube 201 described above except that the slit 270g is formed.

 [0124] That is, the microtube 202 is composed of a microtube body 200g having a slit 240g and a cladding tube 250g having a slit 260g. Then, the slit 270g is formed by communication between the slit 240g and the slit 260g.

 [0125] Here, the fine tube main body 200g is formed to be equal to the fine tube main body 200f described above except for the slit 240g. The slit 240g is formed so as to communicate with the through hole 230 having an opening at a substantially central portion of the side surface of the fine tube main body 200g. The cladding tube 250g is formed to be equal to the above-described cladding tube 250f except for the slit 260g. The slit 260g is formed to have an opening at the substantially central portion of the side surface of the cladding tube 250g so as to communicate with the inside.

 [0126] As described above, since the slit 270g is formed in the microtube 202, it is possible to visually confirm the state in which the end faces of the two optical fibers are connected.

That is, in inserting the two optical fibers into the through-hole 230 in the microtube 202, first, while observing the inside of the slit 270g, until the end face of one optical fiber appears in the back of the slit 270g. One of the optical fibers is inserted into the through hole 230. While observing the inside of the slit 270g, the other optical fiber is inserted into the through hole 230 until the end face of the other optical fiber appears in the back of the slit 270g and contacts the end face of the one optical fiber described above. To do. Thus, if the slit 270g is inserted, the optical fiber inserted into the through hole 230 can be seen, and it is possible to confirm whether or not the end faces of the two optical fibers are in contact with each other. More In addition, if the slit 270g is filled with an adhesive made of a resin material, the two optical fibers can be reliably fixed in contact with each other.

In this modification, the fine tubes 201 and 202 are treated as composite tubes, and the fine tube bodies 200f, 2

00 g may be handled as the fine tube of the above embodiment. That is, the composite tube 201 is a fine tube.

The composite tube 202 is configured to include a fine tube 200g and a cladding tube 250g.

[0129] (Variation 2)

 The micropipe according to this modification is composed of a micropipe main body and two covered pipes that cover a part of the micropipe main body.

[0130] FIG. 10A is a side cross-sectional view of a microtubule according to this modification.

 [0131] The micropipe 203 according to this modification is composed of a micropipe main body 200f and two cladding tubes 250.

 [0132] The fine tube main body 200f is formed to be equal to the fine tube 200 of the above-described embodiment except that the outer diameter d2 is 0.9 mm.

[0133] Each of the two cladding tubes 250 is made of, for example, a metal such as stainless steel, and is formed so that its inner surface is in contact with the outer surface of the fine tube main body 200f and covers one end of the fine tube main body 200f.

 [0134] Both ends of the fine tube main body 200f are respectively inserted into the cladding tube 250 and arranged in a state of being accommodated in the cladding tube 250. That is, the end of each cladding tube 250 protrudes from the end of the fine tube body 200f. The substantially central portion of the fine tube main body 200f is exposed without being covered with the cladding tube 250.

[0135] In the microtube 203 according to this modification, for example, a portion having a coating material of an optical fiber cable is inserted into the recess 220a of the microtube main body 200f from one of the cladding tubes 250, and the optical fiber cable light Only the fiber is passed through the through hole 230 of the fine tube body 200f. Further, the optical fiber cable connected to the above-described optical fiber cable is also inserted from the other cladding tube 250 as described above. As a result, the end faces of the two optical fibers are brought into contact with each other at the approximate center of the microtubule body 200f. Then, the inner surface of the cladding tube 250 and the coating material of the optical fiber cable are fixed by, for example, an adhesive. This allows two lights A fiber cable is connected. The two optical fiber cables may be fixed by pushing a wedge or the like between the inner surface of the cladding tube 250 and the coating material.

[0136] In such a fine tube 203, since the cladding tube 250 is made of a metal, the cladding tube 250 can be welded or soldered to another metal.

03 can be easily and securely fixed to other members.

[0137] Note that a slit may be provided in a substantially central portion of the microtubule 203.

FIG. 10B is a side cross-sectional view of a microtube having a slit.

 [0139] The micropipe 204 is composed of a micropipe main body 200g in which a slit 240g is formed and two cladding tubes 250. The microtube 204 is formed to be equal to the microtube 203 described above except for the slit 240g.

 [0140] In such a fine tube 204, since there is a slit 240g force S, it is possible to visually confirm the state in which the end faces of the two optical fibers are connected.

 [0141] That is, when inserting two optical fibers into the insertion hole 230 in the microtube 204, first, while visually observing the inside of the slit 240g, until the end face of one optical fiber appears in the back of the slit 240g, One optical fiber is inserted into the through hole 230. Then, while observing the inside of the slit 240g, insert the other optical fiber into the through hole 230 until the end surface of the other optical fiber appears in the back of the slit 240g and contacts the end surface of the one optical fiber described above. . Thus, if the slit 240g is fully inserted, the optical fiber inserted into the through hole 230 can be seen, and it is possible to confirm whether or not the end faces of the two optical fibers are in contact with each other. Furthermore, if this slit 240g is filled with an adhesive made of a resin material, the two optical fibers can be securely fixed in contact with each other.

 [0142] In this modification, the fine tubes 203 and 204 may be handled as composite tubes, and the fine tube main bodies 200f and 200g may be handled as the fine tubes of the above embodiment. That is, the composite tube 203 includes a fine tube 200f and two cladding tubes 250, and the composite tube 204 includes a fine tube 200g and two cladding tubes 250.

 [0143] (Variation 3)

 FIG. 11A is a side cross-sectional view of a microtubule according to this modification.

[0144] The microtubule 301 according to this modification has a concave portion instead of the concave portion 220a of the microtubule 200b of Fig. 8B. A portion 320 is formed and formed so as to be equal to the microtube 200b except for the concave portion 320.

 [0145] The recess 320 is formed in the substantially central portion of the two end faces 220 of the microtube 301. The concave portion 320 is formed so that the width in the direction perpendicular to the depth direction is the same at any depth from the end face 220 to a predetermined depth, and further, the depth is increased from the predetermined depth. Accordingly, the width is formed to be small. The bottom of the recess 320 communicates with the through hole 230. The diameter d3 of the opening in the end surface 220 of the recess 320 is, for example, 0.5 mm.

 [0146] Note that a slit may be provided in a substantially central portion of the microtubule 301.

 FIG. 11B is a side sectional view of a microtube having a slit.

 [0148] The microtube 302 is formed with a slit 240c having an opening at a substantially central portion of the side surface of the microtube 302 and communicating with the through hole 230. The opening surface of the slit 240c is an elongated and substantially rectangular shape, and the length of the opening surface along the axial direction of the microtube 302 is, for example, approximately lmm. The microtube 302 is formed so as to be equal to the microtube 301 described above except that the slit 240c is formed.

 [0149] In such a microtube 302, since there is a slit 240c, it is possible to visually confirm the state in which the end faces of the two optical fibers are connected.

 [0150] (Modification 4)

 FIG. 11C is a front sectional view of the microtubule according to this modification.

 [0151] The fine thread field pipes 200 to 204, 200a to 200e, 301, and 302 that are in this modified ί row are inserted in the inner circumferential surface of the 230, and are grooves along the longitudinal direction of the through hole 230. Have 350. The groove 350 is formed from one end to the other end of the through hole 230, that is, from one recess 220a to the other recess 220a of the microtube. The bottom of the groove 350 is formed in a rectangular shape or an arc shape in a cross section perpendicular to the longitudinal direction of the groove 350. The shape of the groove 350 is not limited to the above-described rectangular shape or arc shape, and the shape and dimensions thereof do not affect the arrangement of the optical fibers Fla and F2a passed through the through hole 230. You can set it arbitrarily.

[0152] As described above, in this modified example, since the microtubule has the groove 350, the optical fibers Fla and F2a are inserted. The air in the through-hole 230 confined by the insertion into the through-hole 230 can escape to the outside of the fine tube through the groove 350. As a result, in this modification, the optical fibers Fla and F2a can be smoothly inserted into the through hole 230, and the optical fibers Fla and F2a can be inserted into the inner peripheral surface of the through hole 230. Can be fixed.

Note that even in the case of a microtube having a slit, such as the microtube 200a, the air in the through hole 230 can be released to the outside of the microtube through the slit. However, in such a micro tube having a slit, if the optical fibers Fla and F2a are inserted into the through-hole 230 from different directions and pushed in strongly, the ends of these optical fibers Fla and F2a By pressing, the leading ends of them will warp to the slit side. In other words, the connection loss may increase due to the presence of the slit. Therefore, by forming the groove 350 as described above instead of the slit, the optical fiber can be smoothly inserted and the connection loss can be reliably suppressed.

[0154] In this modification, the groove 350 is formed in the microtubule of the second embodiment, but the groove 350 may be formed in the microtubules 100, 100a to:! OOf of the first embodiment. In this case, the groove 350 is formed along the longitudinal direction of the through hole 130 on the inner peripheral surface constituting the through hole 130 of the microtube.

[Embodiment 3]

 The microtube in the present embodiment is made of metal, not ceramics. That is, the microtube in the present embodiment has the same configuration and dimensions as the microtubule in the second embodiment, but is formed of metal instead of ceramics.

[0156] The fine tube 200 made of such a metal is manufactured by using an electroplating apparatus.

[0157] FIGS. 12A and 12B are configuration diagrams showing the configuration of the electronic apparatus.

[0158] The electric device 30 includes a water tank 31 filled with the electrolytic solution 2, a holding mechanism 35 that holds the core wire 1 linearly, a motor 32 that rotates the holding mechanism 35, and a metal member 33 that serves as an electrode. , A power source 38 for flowing a current between the core wire 1 and the metal member 33 via the electrolyte 2, a pump 34 for circulating the electrolyte 2, and a current for measuring the current flowing in the core 1 And a current control unit 37 that controls the current flowing through the core wire 1 based on the measurement result of the ammeter 36. [0159] For example, nickel metal or an alloy thereof, iron or an alloy thereof, copper or an alloy thereof, cobalt or an alloy thereof, a tungsten alloy, or a fine particle-dispersed metal can be used as the electrolytic solution 2. Nickel, nickel chloride, nickel sulfate, ferrous sulphonate, ferrous borofluoride, copper pyrophosphate, copper sulfate, copper borofluoride, copper copper fluoride, copper titanium fluoride, copper alkanol sulfonate, cobalt sulfate, tungstic acid An aqueous solution mainly composed of an aqueous solution of sodium or the like, or a liquid in which fine powders such as carbon carbide, tantalite carbide, boron carbide, zinc oxide, silicon nitride, alumina, and diamond are dispersed in these liquids. used. Among these, a bath mainly composed of nickel sulfamate is particularly suitable in terms of easiness of electric heating, various physical properties such as hardness, chemical stability, and ease of welding.

 [0160] Core wire 1 is a metal wire such as iron or an alloy thereof, aluminum or an alloy thereof, copper or an alloy thereof, tungsten alloy, or the like, and a thin soldered metal on the metal wire, and a plastic such as nylon or polyester. It is appropriately selected from ceramic wires such as wire and glass. Of these, in the case of plastic and ceramic wires, electroless plating such as nickel and silver is required to impart conductivity to the surface.

 [0161] The side wall of the water tank 31 is formed in, for example, a cylindrical shape having an inner diameter of 1.5 m. The inner periphery of the side wall may be oval. In this case, the major axis of the ellipse is 5m and the minor axis is 1.5m.

 [0162] The holding mechanism 35 includes two disk bodies 35a formed in a disk shape, a plurality of pillars 35b for fixing the two disk bodies 35a so as to face each other at a distance from each other, and a core wire 1 And two elastic bodies 35c for pulling both ends in opposite directions.

 [0163] The core wire 1 is installed on the holding mechanism 35 so that both ends thereof engage with the elastic body 35c. As a result, the core wire 1 is pulled by the elastic body 35c and kept straight.

 [0164] In addition, two molding dies 20 having a shape that fits into the recess 220a of the microtube 200 are attached to the core wire 1 installed in the holding mechanism 35 apart from each other by the length L1 of the microtube 200. It has been. With such a mold 20, it is possible to easily form the recess 220a of the microtube 200.

[0165] As described above, in the present embodiment, only one core wire 1 is immersed in the electrolysis liquid 2. [0166] The motor 32 rotates the core wire 1 by rotating the holding mechanism 35 at a rotation speed of, for example, 1 to 3 seconds per rotation. In FIG. 12A, the motor 32 is disposed below the holding mechanism 35 and the water tank 31; however, the motor 32 may be disposed elsewhere, for example, above the holding mechanism 35 or the water tank. It can be placed above 31.

 [0167] The pump 34 circulates the electrolyte 2 along the inner surface of the water tank 31, thereby making the concentration of the electrolyte 2 in the water tank 31 uniform. The temperature of the electrolyte 2 is kept at 50 ± 2 ° C, for example.

 [0168] The power source 38 passes a current between the core wire 1 and the metal member 33 via the electrolyte 2 so that the core wire 1 becomes a cathode and the metal member 33 becomes an anode, for example. The metal member 33 is composed of a force such as a plurality of nickel balls.

 [0169] The current control unit 37 controls the power supply 38 so that the current flowing through the core wire 1 increases smoothly with time.

 FIG. 13 is a diagram showing a current flowing through the core wire 1.

 [0171] The current control unit 37 controls the power source 38 so that the current flowing through the core wire 1 does not become constant and increases smoothly from 0.5A for 6 hours from the energization time t = 0 to 6, for example. For example, increase the current smoothly so that it does not increase more than 1 A per minute. Thereby, for example, a metal film having a thickness of about 1.25 mm is formed without distortion. That is, the microtube 200 having an outer diameter d2 of 2.5 mm is manufactured with high accuracy. Note that the current increase rate from energization time t = 4 to 6 is larger than the current increase rate from energization time t = 0 to 4.

 [0172] For example, the current control unit 37 has a function of calculating a current value from the energization time, and increases the current along a quadratic curve such as a parabola, a hyperbola, or an elliptical circumference. You can also switch the function according to the energization time.

Here, in the prior art, as indicated by the dotted line in FIG. 13, the current is increased stepwise so that there is a period during which the current flowing through the core wire is constant. For example, a current of 0.2 A continues to flow through the core wire for a while from the energization time t = 0, then the current is increased rapidly and a constant current continues to flow through the core wire for a predetermined period. Therefore, such a stepwise increase in current, that is, a sudden change in current, may cause distortion in the shape and dimensions of the metal coating formed on the core wire. [0174] Therefore, in the present embodiment, by increasing the current smoothly without increasing the current stepwise as in the prior art, the occurrence of distortion of the shape and dimensions of the metal coating, that is, the microtube 200, is prevented. A highly accurate microtube 200 can be manufactured.

 [0175] The metal film thus formed by electric plating is separated from the mold 20 and the core wire 1.

 FIG. 14 is a diagram showing a process of separating the metal coating from the mold 20 and the core wire 1.

[0177] First, after electric heating, the core wire 1 is removed from the holding mechanism 35. A metal film 10a is formed in the area sandwiched between the two forming dies 20 of the core wire 1 that has been removed. Then, the two molds 20 are pulled out from the core wire 1 respectively. As a result, the metal coating 10 a is separated from the mold 20. Further, the core wire 1 is pulled out from the metal coating 10a. Thereby, the tubular metal coating 10a is separated from the core wire 1.

[0178] In the present embodiment, the molding die 20 is made of, for example, ceramic, and integrally includes a substantially conical conical portion 21 having one surface protruding in a tapered shape and a substantially cylindrical cylindrical portion 22. ing . That is, the mold 20 is formed so that the outer periphery of the bottom surface of the conical portion 21 and the outer periphery of the end surface of the cylindrical portion 22 are overlapped to form a pencil shape as a whole. In addition, a hole for inserting the core wire 1 is formed in the axis of the mold 20, that is, the axis of the conical part 21 and the cylindrical part 22.

[0179] Then, the metal coating 10a separated from the core wire 1 and the mold 20 is polished.

FIG. 15 is an explanatory diagram for explaining a state in which the metal coating 10a is polished.

[0181] The metal coating 10a is rubbed with a brush 50 as shown in FIG.

 As shown in (b), burrs and the like of the metal coating 10a are removed, and R is applied to the surface formed by the conical portion 21 of the mold 20 (the surface corresponding to the wall around the recess 220a of the microtube 200). Tick. The metal coating 10a thus polished is completed as a micro tube 200 by being washed.

FIG. 16 is a flowchart showing a method for manufacturing the microtubule 200 in the present embodiment.

[0183] First, only one core wire 1 is immersed in the electrolyte 2 (step S100). Then, the motor 32 rotates the core wire 1 (step S102), and the core wire 1 continues for a predetermined period during which the rotation continues. Electricity is generated by smoothly increasing the current flowing through (step S104). The tubular metal film 10a formed by this electric power is separated from the core wire 1 and the mold 20 (step S106). Further, the separated metal film 10a is polished (step S108), and then washed (step S110).

[0184] (Variation 1)

 A modified example of the electronic apparatus in the above embodiment will be described.

[0185] FIG. 17 is a configuration diagram showing a configuration of a lighting apparatus according to the present modification.

[0186] The electric device 30a allows a current to flow between the water tank 31 filled with the electrolytic solution 2, the motor 32 that rotates the core wire 1, the metal member 33 that serves as an electrode, and the core wire 1 and the metal member 33. A power supply 38 for circulating the electrolytic solution 2, and a watering pipe 39 for spraying the electrolytic solution 2.

 [0187] The core wire 1 on which the molding die 20 is arranged as described above is installed in a water tank 31 filled with the electrolysis liquid 2 in a state of extending in a straight line in the horizontal direction. The motor 32 rotates the core wire 1 thus installed in the circumferential direction. For example, the pump 34 takes in the electrolytic solution 2 at the top of the water tank 31 and supplies it to the sprinkling pipe 39. The water sprinkling pipe 39 is provided at the bottom of the water tank 31, and discharges the electrolyte 2 supplied from the pump 34 from a plurality of water spouts 39a. Thereby, the electrolytic solution 2 in the water tank 1 is circulated and the concentration thereof is made uniform. Note that the temperature of the electrolysis solution 2 is kept substantially constant. The electrolysis solution 2 is, for example, nickel sulfamate.

 In such a state, the power source 38 causes a current to flow between the core wire 1 and the metal member 33 via the electrolyte 2 so that the core wire 1 is a cathode and the metal member 33 is an anode, for example. As a result, a metal film is formed on the surface of the core wire 1 sandwiched between the molds 20.

 [0189] (Modification 2)

 Here, a modification of the mold 20 in the above embodiment will be described.

 [0190] The mold 20 of the above embodiment includes the conical portion 21 and the cylindrical portion 22, but as long as it has a conical portion, it may be formed in another shape as a whole. Good.

 FIG. 18A to FIG. 18C are views showing the shape of a mold according to this modification.

[0192] For example, as shown in FIG. 18A, a molding die 20a according to the present modification includes a substantially cylindrical column part 2 2a and a substantially conical conical portion 21a projecting from one end face of the cylindrical portion 22a. In this molding die 20a, unlike the molding die 20, the outer periphery of the bottom surface of the conical portion 21a does not overlap the outer periphery of the end surface of the cylindrical portion 22a.

 Further, as shown in FIG. 18B, a molding die 20b according to the present modification includes the above-described cylindrical portion 22a and the above-described conical portions 21a that are projected from both end surfaces of the cylindrical portion 22a. It is prepared. In this mold 20b, the outer periphery of the bottom surface of the conical part 21a and the outer periphery of the end surface of the cylindrical part 22a do not overlap, similar to the mold 20a. Thus, since one mold 20b has two conical portions 21a, if three or more of these molds 20b are arranged on one core wire 1 in the electric apparatus, a plurality of micro tubes 200 are formed. It can be manufactured efficiently.

 Further, as shown in FIG. 18C, a molding die 20c according to this modification includes the above-described two conical portions 21, and a so-called abacus ball in which the bottom surfaces of the conical portions 21 face each other. It is formed in a shape. In this mold 20c, the outer circumferences of the bottom surfaces of the two conical portions 21 are overlapped. As described above, since one molding die 20c has two conical portions 21 as described above, if three or more of these molding dies 20c are arranged on one core wire 1 in the electrical apparatus, a plurality of molding dies 20c are arranged. The microtube 200 can be manufactured efficiently.

 [0195] Thus, in the present embodiment, since only one core wire 1 is immersed in the electrolyte 2, the metal formed on the core wire 1 that is not electrically affected by other core wires. It is possible to prevent distortion of the shape of the coating 10a. As a result, if the core wire 1 is cut through the tubular metal coating 10a, the microtube 200 made of the tubular metal coating 10a can be manufactured with high accuracy. Therefore, since the microtube 200 manufactured by such a manufacturing method has no distortion, the optical fibers can be appropriately connected.

[0196] In the above-described embodiment, the electric power is applied to only one core wire 1. However, the electric power may be applied to a plurality of core wires 1. In this case, for example, the inside of the water tank 31 is partitioned, and a plurality of regions for storing the electrolytic solution 2 are provided in the water tank 31. The electrolytes 2 accumulated in each of these areas are electrically insulated from each other. Then, only one core wire 1 is immersed in the electrolysis liquid 2 for each region, and the wire 1 is electroplated in the same manner as described above. As a result, as described above, only one core wire 1 is immersed in the electrolyte 2 in each region, and the electrolyte 2 in each region is electrically insulated. Metal coating formed on 1 Oa is not affected by other core wires as in the conventional example.

It is possible to prevent the shape of the metal coating 10a formed on 1 from being distorted. as a result

If each core wire 1 is pulled out from each tubular metal coating 10a, a plurality of microtubules 200 made of each tubular metal coating 10a can be manufactured with high accuracy.

[0197] Although the microtubules of the present invention have been described above using Embodiments 1 to 3 and modifications thereof, the present invention is not limited to these.

[0198] For example, the outer diameter of the fine tube may be 0.07 mm to 10 mm, and the total length of the fine tube may be 45 cm or more. Furthermore, the force may be 3 x m or less, where the coaxiality of the micropipe is 1 / im.

 [0199] Also, when connecting the optical fibers Fla and F2a, the ends of the optical fibers are processed into a so-called slanted cut into an elliptical force S, and a plane perpendicular to the longitudinal direction of the optical fiber is formed. It may be processed into a circle.

 [0200] Further, the microtubule may be composed of force S composed of dinolecon oxide and aluminum nitride. The thermal conductivity of aluminum nitride is approximately 160 to 180 W / m′K, which is higher than that of zirconium oxide. Therefore, such a micro tube made of aluminum nitride can be used in places and applications where excellent heat conductivity such as heat dissipation is required. For example, it can be attached to an endoscope or a special optical fiber. It can be applied to ferrules and light emitting devices.

 [0201] In other words, in recent years, the importance of heat dissipation and cooling technology for electronic components and equipment has increased more and more with high-density mounting technology and higher output and higher speed of devices. For example, in CPUs (Central Processing Units) and the like, while miniaturization and speeding-up are performed, the heat density increases, and CPU heat-dissipation cooling technology is a major issue.

 [0202] Therefore, it is expected that the above-mentioned precision micropipe of aluminum nitride will be used as a member used in heat pipes, heat sinks, and Peltier devices that serve as a tool for solving this problem. In other words, this precision micropipe is used for thermal design, cooling methods, and cooling devices.

[0203] The fine tube may be made of, for example, quartz glass. In this case, the thermal expansion coefficient of the micropipe and the thermal expansion coefficient of the optical fiber are approximately equal, so the connection is made according to changes in ambient temperature. It is possible to suppress the occurrence of loss. Furthermore, since the fine tube has translucency, the connection state of the end portions of the two optical fibers can be visually observed, and the usability can be improved. Note that the microtube may be made of a light-transmitting material (glass or the like) other than quartz glass.

Industrial applicability

 The microtubule of the present invention has an effect of reducing the connection loss of light, and is suitable for parts used for connecting optical fibers.

Claims

The scope of the claims

 [1] The tube is configured as a tube having an outer diameter of 2.5 mm or less, and the end surface of the optical fiber inserted into one end of the tube is in contact with the end surface of the optical fiber inserted from the other end of the tube. Two micro-tubes that keep the portions of the optical fibers inserted into the tube in a straight line, made of ceramics,

 The coaxiality indicating the deviation width between the central axis on the outer peripheral surface of the microtube and the central axis on the inner peripheral surface of the microtube is formed to be within 3 μm.

 A fine tube characterized by that.

[2] The microtubule is made of dinoleconium oxide

 2. The microtubule according to claim 1, wherein

[3] At both ends of the microtube,

 A recess having an opening having a diameter larger than the diameter of the hole is formed in communication with the hole surrounded by the inner peripheral surface.

 3. The microtube according to claim 2, wherein

[4] The recess is formed such that a width of the recess in a direction perpendicular to the depth direction is substantially constant along the depth direction.

 4. The microtubule according to claim 3, wherein:

[5] The concave portion is formed such that a width of the concave portion in a direction perpendicular to the depth direction is narrowed toward a depth direction in the depth direction.

 4. The microtubule according to claim 3, wherein:

[6] The width of the concave portion in the direction perpendicular to the depth direction of the concave portion is substantially constant along the depth direction from the opening to a predetermined depth, and from the predetermined depth to the depth direction. It is formed so as to narrow toward the depth

 4. The microtubule according to claim 3, wherein:

[7] The fine tube is formed with a slit having an opening on the outer peripheral surface and communicating with the hole.

 7. The microtubule according to claim 6, wherein

[8] The inner surface of the microtubule continues from one of the recesses to the other recess. Grooves are formed

 4. The fine tube according to claim 3, wherein

[9] The microtubule according to claim 1;

 A cladding tube covering the fine tube,

 Both ends of the cladding tube protrude from the fine tube.

 A composite tube characterized by that.

[10] At both ends of the microtube,

 A recess having an opening having a diameter larger than the diameter of the hole is formed in communication with the hole surrounded by the inner peripheral surface.

 10. The microtubule according to claim 9, wherein

[11] In the microtube, a first slit having an opening on the outer peripheral surface and communicating with a hole surrounded by the inner peripheral surface of the microtube is formed.

 The cladding tube is formed with a second slit communicating with the first slit of the fine tube.

 11. The composite pipe according to claim 10, wherein

[12] The microtubule according to claim 1;

 A first cladding tube covering one end of the fine tube;

 A second cladding tube covering the other end of the fine tube,

 The first cladding tube protrudes from one end of the microtube;

 The second cladding tube protrudes from the other end of the fine tube

 A composite tube characterized by that.

[13] At both ends of the microtube,

 A recess having an opening having a diameter larger than the diameter of the hole is formed in communication with the hole surrounded by the inner peripheral surface.

 13. The microtubule according to claim 12, wherein the microtubule is characterized in that:

[14] The fine tube has an opening in an exposed portion of the outer peripheral surface, and a slit is formed that communicates with a hole that is surrounded by the inner peripheral surface of the fine tube.

14. The composite pipe according to claim 13, wherein the composite pipe is characterized in that:

[15] The microtubule is made of aluminum nitride.

 2. The microtubule according to claim 1, wherein

[16] The coaxiality is formed to be within 1 μ.

 2. The microtubule according to claim 1, wherein

[17] A fine tube with an outer diameter of 2.5 mm or less,

 Made of ceramics,

 The coaxiality indicating the deviation width between the central axis on the outer peripheral surface of the microtube and the central axis on the inner peripheral surface of the microtube is formed to be within 3 μm.

 A fine tube characterized by that.

[18] The inner diameter of the microtubule is within 125 μm, and the total length of the microtubule is 45 cm or more.

 18. The microtube according to claim 17, wherein the microtube is characterized in that:

[19] An optical fiber connecting method for connecting two optical fibers using a micro tube having an outer diameter of 2.5 mm or less,

 The microtube is made of ceramics, and is formed so that the coaxiality indicating the deviation width between the central axis on the outer peripheral surface of the microtube and the central axis on the inner peripheral surface of the microtube is within 3 μΐη,

 The connection method includes:

 For each optical fiber to be connected, a processing step for processing the end so that the end surface of the optical fiber is inclined at a predetermined angle with respect to a surface perpendicular to the axial direction at the end of the optical fiber; ,

 A first insertion step of inserting one optical fiber covered in the processing step from one end of the microtube into a hole surrounded by the inner peripheral surface;

 The second optical fiber which is brought into contact with the end faces of the two optical fibers facing each other by inserting the other optical fiber cabled in the processing step into the hole from the other end of the microtube. When

 A connection method comprising:

[20] Openings having a diameter larger than the diameter of the hole communicated with the hole at both ends of the microtube A recess having

 In the first insertion step,

 The one optical fiber is inserted into the hole until the covering material covering the one optical fiber comes into contact with the bottom surface of the recess formed at one end of the microtube,

 The other optical fiber is inserted into the hole until the covering material covering the other optical fiber contacts the bottom surface of the recess formed at the other end of the microtube.

 20. The connecting method according to claim 19, wherein the connecting method.

[21] The connection method further includes:

 A bonding step of bonding the inner surface of the concave portion of the microtubule and the coating material of the optical fiber via a resin material

 21. The connection method according to claim 20, wherein

[22] The fine tube is covered with a cladding tube, and both ends of the cladding tube protrude from the fine tube,

 In the bonding step,

 The inner surface of the end portion of the cladding tube and the coating material of the optical fiber are bonded via a resin material.

 22. The connection method according to claim 21, wherein the connection method is characterized in that:

[23] The microtube is formed with a first slit having an opening on the outer peripheral surface and communicating with the hole,

 The cladding tube is formed with a second slit that communicates with the first slit of the microtube, and in the first insertion step,

 While visually observing the inside of the first and second slits, the one optical fiber is inserted into the hole until the end face of the one optical fiber appears in the back of the first and second slits, and the second In the insertion process,

While observing the inside of the first and second slits, until the end face of the other optical fiber appears in the back of the first and second slits and contacts the end face of the one optical fiber, the other light is used. Insert the fiber into the hole 23. The connecting method according to claim 22, wherein the connecting method is characterized in that:

[24] The connection method further includes:

 A fixing step of fixing the two optical fibers in a state where end surfaces of the two optical fibers are in contact with each other by pouring a resin material into the first and second slits. The method of consolidation as described in item 23.

[25] One end of the microtube is covered with a first cladding tube, and the first cladding tube protrudes from one end of the microtube,

 The other end of the microtube is covered with a second cladding tube, and the second cladding tube projects from the other end of the microtube,

 In the bonding step,

 The inner surface of the end portion of the first cladding tube and the coating material of the one optical fiber are bonded via a resin material, and the inner surface of the end portion of the second cladding tube and the coating of the other optical fiber The material is bonded with resin material

 22. The connection method according to claim 21, wherein the connection method is characterized in that:

[26] The fine tube is formed with a slit having an opening on the exposed outer peripheral surface and communicating with the hole,

 In the first insertion step,

 While observing the inside of the slit, until the end face of the one optical fiber appears in the back of the slit, the one optical fiber is inserted into the hole,

 In the second insertion step,

 While visually observing the inside of the slit, the other optical fiber is inserted into the hole until the end surface of the other optical fiber appears in the back of the slit and contacts the end surface of the one optical fiber.

 26. The connection method according to claim 25.

[27] The connection method further includes:

 A fixing step of fixing the two optical fibers in a state where the end faces of the two optical fibers are in contact with each other by pouring a resin material into the slit;

 27. The connection method according to claim 26, characterized by that.