Optical connector connection structure

Abstract

A magnetic structure (22a) integrated with a ferrule (20a) is composed of a soft magnetic material. A magnetic structure (22b) integrated with a ferrule (20b) is composed of a soft magnetic material the length of which in the longitudinal direction of optical fibers (1a, 1b) is shorter than that of the magnetic structure (22a). After the connection end surfaces of the ferrules (20a, 20b) are connected to each other, magnetic structures (40, 41) composed of hard magnetic materials are mounted to an opposite end surface side of the magnetic structure (22b) from a connection end surface connected to the magnetic structure (22a).

Description

[Technical field]

[0001] The present invention relates to a technique for connecting optical connectors together, and more particularly to an optical connector connection structure that is easy to attach and detach even while using magnetic force. [Background technology]

[0002] In response to the growing need for optical interconnects within data centers, there is a growing need for multi-core optical connectors, such as MT connectors and MPO connectors. In both MT and MPO connectors, the connecting end faces of the opposing ferrules are positioned with mating pins. When connecting single-mode fibers using MT connectors, an alignment material is used between the connecting end faces of the ferrules. When connecting single-mode fibers using MPO connectors, a PC (Physical Contact) connection is made by making the connecting end faces of the ferrules beveled and applying a pressure of about 10-20N to press the connecting end faces together.

[0003] In both MT and MPO connectors, a pressing mechanism using mechanical elements such as springs and clips is used to press the connection end faces of the ferrules together and maintain the connection state. However, there are limitations on how small the connectors can be made due to space restrictions for holding and attaching / detaching the mechanical elements.

[0004] As a means of achieving miniaturization, an optical connector has been proposed that does not use mechanical elements such as springs and clips, but instead has magnets attached around the ferrules so that the ferrules are pressed together by the magnetic force emitted from the magnets (see Non-Patent Document 1).

[0005] However, the configuration using magnets has a problem that it is difficult to attach and detach the optical connector because the connection between the connection end faces of the ferrules and the connection between the magnets attached to the ferrules occur simultaneously. In other words, when a magnetic attractive force of, for example, about 10 N is applied between the optical connectors, when separating the two connected optical connectors, a force larger than the magnetic attractive force must be applied in the opposite direction to the magnetic attractive force, making it difficult to disconnect. In addition, when separating the optical connectors, there is a possibility that the guide pins and the like may be deformed. In addition, when connecting two optical connectors, the magnetic attractive force between the optical connectors is large, so that the magnets may collide with each other with force, causing the magnets to chip. [Prior art documents] [Non-patent literature]

[0006] [Non-Patent Document 1] Kota Shikama,Norio Sato,Atsushi Aratake,Satoshi Shigematsu,and Takeshi Sakamoto,“Miniature Optical Connector with Magnetic Physical Contact”,Proc. Optical Fiber Communication Conference 2020,W2A Summary of the Invention [Problem to be solved by the invention]

[0007] The present invention has been made to solve the above-mentioned problems, and has an object to provide an optical connector connection structure that can improve the workability of attaching and detaching an optical connector. [Means for solving the problem]

[0008] The optical connector connection structure of the present invention is composed of a first optical connector attached to an end of a first optical fiber, and a second optical connector attached to an end of a second optical fiber and connectable to the first optical connector, the first optical connector comprising a first alignment part configured to fix the first optical fiber, and a first magnetic structure integrated with the first alignment part, the second optical connector comprising a second alignment part configured to fix the second optical fiber, and a second magnetic structure integrated with the second alignment part, the first magnetic structure being made of a soft magnetic material, and the second magnetic structure being made of a soft magnetic material. The magnetic structure is made of a soft magnetic material having a length in the longitudinal direction of the optical fiber shorter than that of the first magnetic structure, and a third magnetic structure made of a hard magnetic material is disposed on the end face side of the second magnetic structure opposite to the end face connected to the first magnetic structure, and the third magnetic structure is made of two hard magnetic materials, and the magnetization directions of the N pole and S pole of the two hard magnetic materials are set along the longitudinal direction of the first and second optical fibers, and are set so that the magnetization directions of the N pole and S pole of the two hard magnetic materials are opposite to each other, and the cylindrical third magnetic structure combining the two hard magnetic materials is attached around the second alignment component. The second magnetic structure is made of two or more soft magnetic materials, and these soft magnetic materials are arranged around the second alignment component in a state where they are spaced apart from each other via a gap filled with air or a non-magnetic material, and the gap is provided at a position near the connection part of the two hard magnetic materials that constitute the third magnetic structure. It is characterized by the above.

[0009] The optical connector connection structure of the present invention The optical connector is composed of a first optical connector attached to a tip of a first optical fiber and a second optical connector attached to a tip of a second optical fiber and connectable to the first optical connector, the first optical connector comprises a first alignment part configured to fix the first optical fiber and a first magnetic structure integrated with the first alignment part, the second optical connector comprises a second alignment part configured to fix the second optical fiber and a second magnetic structure integrated with the second alignment part, the first magnetic structure is made of a soft magnetic material, and the second magnetic structure is made of a soft magnetic material having a length in a longitudinal direction of the optical fiber shorter than that of the first magnetic structure. a third magnetic structure made of a hard magnetic material is disposed on an end face of the second magnetic structure opposite to the end face connected to the first magnetic structure, and a fourth magnetic structure made of a soft magnetic material is disposed on an end face of the third magnetic structure opposite to the end face connected to the second magnetic structure, the third magnetic structure is made of two hard magnetic materials, and the magnetization directions of the N pole and S pole of the two hard magnetic materials are set along the longitudinal direction of the first and second optical fibers, and the magnetization directions of the N pole and S pole of the two hard magnetic materials are set to be opposite to each other, and the cylindrical third magnetic structure combining the two hard magnetic materials is attached around the second alignment component, The fourth magnetic structure is made of two or more soft magnetic materials, and the fourth magnetic structure is a cylindrical structure made by combining these soft magnetic materials and is attached around the second alignment component. a connecting position of the two hard magnetic materials constituting the third magnetic structure is different from a connecting position of the two or more soft magnetic materials constituting the fourth magnetic structure. It is characterized by the above.

[0010] Furthermore, in one configuration example of the optical connector connection structure of the present invention, the first and second alignment parts and the first and second magnetic structures are characterized in that they each have positioning structures for determining the positional relationship between the first alignment part and the first magnetic structure, and the positional relationship between the second alignment part and the second magnetic structure. In one configuration example of the optical connector connection structure of the present invention, the second magnetic structure is molded integrally with the second alignment part. Effect of the Invention

[0013] According to the present invention, the first magnetic structure is made of a soft magnetic material, the second magnetic structure is made of a soft magnetic material whose length in the longitudinal direction of the optical fiber is shorter than that of the first magnetic structure, and a third magnetic structure made of a hard magnetic material can be attached to the end face of the second magnetic structure opposite the connection end face with the first magnetic structure.This allows the connection of the connection end faces of the first and second alignment parts and the attachment of the third magnetic structure to be performed in separate processes, thereby improving the ease of attaching and detaching the optical connector. [Brief description of the drawings]

[0014] [Figure 1A] FIG. 1A is a perspective view of a multi-fiber optical connector connection structure according to a first embodiment of the present invention before ferrule connection. FIG. [Figure 1B] FIG. 1B is a perspective view of the multi-core optical connector connection structure according to the first embodiment of the present invention after ferrule connection. [Diagram 2] FIG. 2 is a perspective view of a state in which a magnet is attached after ferrule connection of the multi-core optical connector connection structure according to the first embodiment of the present invention. [Figure 3A] FIG. 3A is a cross-sectional view of the multi-core optical connector connection structure according to the first embodiment of the present invention after ferrule connection. [Figure 3B] FIG. 3B is a cross-sectional view of the multi-core optical connector connection structure according to the first embodiment of the present invention in a state where a magnet is attached after ferrule connection. [Figure 4A-4B] 4A and 4B are perspective views illustrating a method for mounting the third magnetic structure according to the first embodiment of the present invention. [Figure 5A-5B] 5A and 5B are perspective views illustrating a method for removing the third magnetic structure according to the first embodiment of the present invention. [Figure 6A-6B]6A and 6B are cross-sectional views showing another example of the multi-core optical connector connection structure according to the first embodiment of the present invention. [Figure 7A-7C] 7A to 7C are cross-sectional views illustrating a method for joining the first magnetic structure and a ferrule according to the first embodiment of the present invention. [Figure 8A-8C] 8A to 8C are cross-sectional views illustrating a method for joining the second magnetic structure and a ferrule according to the first embodiment of the present invention. [Figure 9A-9D] 9A to 9D are diagrams illustrating a method of positioning the third magnetic structure and the ferrule according to the first embodiment of the present invention. [Figure 10A] FIG. 10A is a perspective view of a multi-fiber optical connector connection structure according to a second embodiment of the present invention before ferrule connection. [Figure 10B] FIG. 10B is a perspective view of the multi-core optical connector connection structure according to the second embodiment of the present invention after ferrule connection. [Figure 11] FIG. 11 is a perspective view of a state in which a magnet is attached after ferrule connection in a multi-core optical connector connection structure according to a second embodiment of the present invention. [Figure 12A] FIG. 12A is a cross-sectional view showing magnetic flux density vectors when there is no gap in the second magnetic structure of the multi-core optical connector connection structure. [Figure 12B] FIG. 12B is a cross-sectional view showing magnetic flux density vectors in the multi-core optical connector connection structure according to the second embodiment of the present invention. [Figure 13A] FIG. 13A is a perspective view of a multi-core optical connector connection structure according to a third embodiment of the present invention before ferrule connection. [Figure 13B] FIG. 13B is a perspective view of the multi-core optical connector connection structure according to the third embodiment of the present invention after ferrule connection. [Figure 14] FIG. 14 is a perspective view of a multi-core optical connector connection structure according to a third embodiment of the present invention in a state where a magnet is attached after ferrule connection. [Figure 15A] FIG. 15A is a perspective view of a multi-core optical connector connection structure according to a fourth embodiment of the present invention before ferrule connection. [Figure 15B] FIG. 15B is a perspective view of the multi-core optical connector connection structure according to the fourth embodiment of the present invention after ferrule connection. [Figure 16] FIG. 16 is a perspective view of a multi-core optical connector connection structure according to a fourth embodiment of the present invention in a state where a magnet is attached after ferrule connection. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] [First Example] Hereinafter, the embodiments of the present invention will be described in detail with reference to the drawings. Fig. 1A is a perspective view of a multi-core optical connector connection structure according to a first embodiment of the present invention before ferrule connection, and Fig. 1B is a perspective view of the multi-core optical connector connection structure after ferrule connection. Fig. 2 is a perspective view of a state in which a magnet is attached after ferrule connection of the multi-core optical connector connection structure. Fig. 3A is a cross-sectional view of the multi-core optical connector connection structure of Fig. 1B cut along the YZ plane, and Fig. 3B is a cross-sectional view of the multi-core optical connector connection structure of Fig. 2 cut along the YZ plane.

[0016] The multi-core optical connector connection structure of this embodiment is composed of an optical connector 2a attached to the ends of multiple optical fibers 1a, an optical connector 2b attached to the ends of multiple optical fibers 1b, and a guide pin 3 that connects the ferrules of the optical connectors 2a, 2b.

[0017] The optical connector 2a is composed of a ferrule 20a (first alignment part) attached to the tip of the optical fiber 1a, a boot 21a that bundles the optical fiber 1a, and a magnetic structure 22a (first magnetic structure) attached around the ferrule 20a. Similarly, the optical connector 2b is composed of a ferrule 20b (second alignment part) attached to the tip of the optical fiber 1b, a boot 21b that bundles the optical fiber 1b, and a magnetic structure 22b (second magnetic structure) attached around the ferrule 20b.

[0018] The optical fibers 1a and 1b each have a cladding diameter of, for example, 125 μm, a core diameter of approximately 10 μm, and are eight-core silica-based single-mode fibers arranged at a pitch of approximately 250 μm.

[0019] The ferrules 20a and 20b are multi-core ferrules having a plurality of microholes into which the plurality of optical fibers 1a and 1b are inserted. The ferrules 20a and 20b are known MT ferrules, and have two guide pin holes 23a and two guide pin holes 23b that penetrate the ferrules 20a and 20b along the longitudinal direction (Z-axis direction) of the optical fibers 1a and 1b.

[0020] An optical fiber 1a from which the coating has been removed is inserted into each of the microholes of the ferrule 20a. Similarly, an optical fiber 1b from which the coating has been removed is inserted into each of the microholes of the ferrule 20b. The optical fibers 1a and 1b are fixed to the ferrules 20a and 20b with an adhesive. Note that the adhesive and the optical fiber coating are not shown in Figures 1A, 1B, 2, 3A, and 3B.

[0021] The opposing connection end faces of the ferrules 20a, 20b, the opposing connection end faces of the optical fibers 1a, 1b, and the opposing connection end faces 24a, 24b of the magnetic structures 22a, 22b are perpendicular to the Z-axis direction. The optical fibers 1a and 1b are positioned so as to slightly protrude from the connecting end faces of the ferrules 20a and 20b, respectively, and the connecting end faces of the optical fibers 1a and 1b are polished.

[0022] The connection end face 24a of the magnetic structure 22a and the connection end face of the ferrule 20a are positioned to be aligned on the same plane, but the connection end face of the ferrule 20a may be positioned to protrude relative to the connection end face 24a of the magnetic structure 22a. Similarly, the connection end face 24b of the magnetic structure 22b and the connection end face of the ferrule 20b are positioned to be aligned on the same plane, but the connection end face of the ferrule 20b may be positioned to protrude relative to the connection end face 24b of the magnetic structure 22b.

[0023] The magnetic structure 22b is set to have a shorter length in the Z-axis direction than the magnetic structure 22a and the ferrules 20a and 20b. The length of the magnetic structure 22b in the Z-axis direction is, for example, about 1 mm. On the other hand, the length of the magnetic structure 22a in the Z-axis direction is approximately the same as the lengths of the ferrules 20a and 20b, for example, about 6 mm.

[0024] 1A and 1B, in this embodiment, the guide pins 3 are inserted one by one into the two guide pin holes 23b of the ferrule 20b of the optical connector 2b, and these guide pins 3 are inserted into the guide pin holes 23a of the ferrule 20a of the optical connector 2a to butt the connection end faces of the ferrules 20a and 20b together and to butt the connection end faces of the optical fibers 1a and 1b together, thereby connecting the optical connectors 2a and 2b. The positioning of the ferrules 20a and 20b relative to each other, i.e., the positioning of the optical fibers 1a and 1b relative to each other, is performed by the guide pins 3.

[0025] Both the magnetic structures 22a and 22b are made of a soft magnetic material. Known soft magnetic materials include metals that are attracted to magnets, such as iron, nickel, cobalt, and permalloy. In addition, stainless steel (SUS), which is an iron-based alloy, that has magnetism (such as SUS430) can also be used. The ferrules 20a, 20b and the magnetic structures 22a, 22b may be joined by any of adhesion, mechanical fitting, and metal joining (solder, etc.).

[0026] In this embodiment, the magnetic structures 40, 41 (third magnetic structures) are arranged on the end face side opposite to the connection end face 24b of the magnetic structure 22b. The magnetic structures 40, 41 are made of a hard magnetic material (so-called magnet). If the longitudinal direction of the optical fibers 1a, 1b is the Z-axis direction, the magnetization directions of the N and S poles of the magnetic structures 40, 41 are set along the Z-axis direction. As the material of the magnet, any known magnet may be used depending on the magnetic force to be generated. A typical magnet may be a neodymium magnet. Other known magnets such as ferrite magnets, alnico magnets, samarium cobalt magnets, KS steel, MK steel, and neodymium iron boron magnets may be used as the magnetic structures 40, 41. Naturally, any magnet whose magnetic properties are adjusted by slightly changing the composition of these magnets may be used in the same way.

[0027] As shown in FIG. 2, the magnetic structures 40 and 41 are each made of a hard magnetic material having a half-split structure obtained by splitting a square tube in half. By combining the magnetic structures 40 and 41 to form a square tube shape, a part of the ferrule 20b can be accommodated inside the tube. As described above, the magnetization directions of the north and south poles of the magnetic structures 40 and 41 are set along the Z-axis direction, but the magnetization directions of the north and south poles are set to be opposite to each other so that they are integrated by magnetic attraction. For example, in the example of FIG. 2, the magnetization direction of the magnetic structure 40 is set so that the south pole is in the order of north pole along the Z-axis direction from the magnetic structure 22b side, while the magnetization direction of the magnetic structure 41 is set so that the north pole is in the order of south pole along the Z-axis direction from the magnetic structure 22b side.

[0028] The magnetic structures 40 and 41 do not necessarily need to be integrated with the ferrules 20a and 20b. The magnetic structures 40 and 41 are coupled to the magnetic structure 22b by magnetic attraction, but since they are not fixed to the ferrule 20b, they can be freely attached and detached.

[0029] The method of mounting the magnetic structures 40 and 41 will be described with reference to Figures 4A and 4B. The method of butting the ferrules 20a and 20b together is as described above. At this time, since no magnetic attractive force is generated between the magnetic structures 22a and 22b made of soft magnetic material, the connection can be easily completed by pressing the ferrules 20a and 20b together with a jig or manually.

[0030] Next, the magnetic structures 40 and 41 are combined to form a rectangular tube shape so that the optical fiber 1a is inserted inside the tube. The magnetic structures 40 and 41 are integrated together by magnetic attraction. Then, as shown in FIG. 4B, the integrated magnetic structures 40 and 41 are brought close to the magnetic structure 22b, whereby the magnetic structure 22b and the magnetic structures 40 and 41 are connected together by magnetic attraction. The ferrule 20b is housed inside the cylindrical magnetic structures 40 and 41.

[0031] In order to prevent the magnetic structures 40 and 41 from suddenly colliding with the magnetic structure 22b, it is preferable to gradually bring them closer to each other via a jig or the ring component 42 shown in Fig. 4A. By avoiding a sudden collision, chipping of the magnetic structures 40 and 41 can be prevented.

[0032] When the magnetic structure 22b and the magnetic structures 40 and 41 are coupled together, a magnetic attractive force also acts between the magnetic structures 22a and 22b. Since the length of the magnetic structure 22b in the Z-axis direction is short, a sufficient magnetic attractive force acts between the magnetic structures 22a and 22b. As a result, the connection end faces of the ferrules 20a and 20b integrated with the magnetic structures 22a and 22b are pressed against each other, and at the same time, a force is applied to press the connection end faces of the optical fibers 1a and 1b protruding from the ferrules 20a and 20b against each other.

[0033] By setting the size of each of the magnetic structures 22a, 22b, 40, 41, the gap between the magnetic structures 22a, 22b, and the material of the magnetic structures 22a, 22b, 40, 41 so that the magnetic attractive force is, for example, 10 N, it is possible to press the connection end faces of the optical fibers 1a, 1b against each other in the same manner as in an MT connector or an MPO connector. In this way, a PC connection can be realized.

[0034] In the structures shown in Figures 1A, 1B, 2, 3A, 3B, 4A, and 4B, the magnetic structures 22a, 22b, 40, and 41 are arranged so as to surround the ferrules 20a and 20b, but the structures may not be those shown in Figures 1A, 1B, 2, 3A, 3B, 4A, and 4B as long as they can generate magnetic force. For example, the magnetic structures may be arranged on only one side of the ferrules 20a and 20b.

[0035] Also, the magnetic structures 40, 41 may not be a combination of two half-split structures, but may be two or more hard magnetic materials, for example, a multi-pole magnet with four or eight poles. Moreover, for the magnetic structures 22a and 22b, any structure may be used as long as it satisfies the requirements of the present invention, and each may be a combination of two or more structures.

[0036] Next, a method of removing the magnetic structures 40, 41 will be described with reference to Figs. 5A and 5B. When disconnecting the optical connectors 2a and 2b, the magnetic structures 40, 41 are removed first. To remove the magnetic structures 40, 41, as shown in Fig. 5A, a force in a direction different from the longitudinal direction (Z-axis direction) of the optical fibers 1a and 1b is applied to the magnetic structures 40, 41, so that the magnetic structures 40, 41 can be disconnected from the magnetic structure 22b with a smaller force than pulling the magnetic structures 40, 41 in the Z-axis direction. Note that Fig. 5A illustrates an example in which the magnetic structures 40, 41 are removed by rotating them around the Z-axis, but this is not limited to this method. The magnetic structures 40, 41 may be removed by pulling them in the X-axis direction or by rotating them around the Y-axis. In either case, the magnetic structures 40, 41 can be disconnected from the magnetic structure 22b with a smaller force than pulling the magnetic structures 40, 41 in the Z-axis direction.

[0037] The magnetic structures 40 and 41 may be removed as they are, or may be moved away from the magnetic structure 22b as shown in Fig. 5B. By removing the magnetic structures 40 and 41 from the magnetic structure 22b, the magnetic attractive force between the magnetic structures 22a and 22b disappears, so the connection between the ferrules 20a and 20b can be released by using a jig or manually.

[0038] In this embodiment, the connection end faces of the ferrules 20a, 20b can be attached and detached in separate steps from the attachment and detachment of the magnetic structures 40, 41, making it possible to easily attach and detach the optical connectors 2a, 2b.

[0039] In the conventional configuration disclosed in Non-Patent Document 1, the magnetic structure integrated with the ferrule is a magnet. Therefore, in order to release the connection between the ferrules, it is necessary to apply a force in the opposite direction that is greater than the magnetic attractive force acting between the magnetic structure integrated with the ferrule, to separate the two ferrules. However, when the magnetic attractive force is, for example, about 10 N, it is necessary to apply a large force using a dedicated jig, etc., making it difficult to release the connection. In addition, excessive force is applied to the ferrule and guide pin when separating the two ferrules, which may cause the ferrule and guide pin to deform and break.

[0040] On the other hand, in this embodiment, when disconnecting the optical connectors 2a and 2b, it is sufficient to disconnect the ferrules 20a and 20b after removing the magnetic structures 40, 41, so that the connection can be disconnected with little force, improving the workability when disconnecting.

[0041] In addition, in the conventional configuration disclosed in Non-Patent Document 1, when connecting ferrules, it is necessary to fit the guide pin into the guide pin hole of the ferrule while a large magnetic attractive force acts between the magnetic structure integrated with the ferrule, and there is a problem with the workability at the time of connection. In addition, there is a possibility that the magnetic structure will be chipped due to the magnetic structures colliding with each other with force, and that the powder of the magnetic structure will adhere to the connecting end surface of the ferrule, deteriorating the optical characteristics.

[0042] On the other hand, in this embodiment, by adopting a configuration in which the magnetic structures 40 and 41 are attached later, there is no need to be concerned about the magnetic attractive force between the magnetic structures 22a and 22b when connecting the ferrules 20a and 20b, and therefore workability during connection can be improved. The magnetic structures 40 and 41 are attached after the connection of the ferrules 20a and 20b, but since they are not attached at the same time as the connection of the ferrules 20a and 20b, it is possible to easily prevent a sudden collision between the magnetic structures 22b and the magnetic structures 40 and 41 by using a jig or the above-mentioned ring part 42, etc.

[0043] Furthermore, in this embodiment, even if chipped powder of the magnetic structures 40, 41 occurs, it is unlikely that the powder will adhere to the connection end faces of the ferrules 20a, 20b after the connection between the ferrules 20a and 20b is completed, and the optical characteristics are unlikely to deteriorate.

[0044] Next, other components of the present invention will be described. In the present invention, any known type and material of the optical fibers 1a and 1b and the type and material of the ferrules 20a and 20b can be applied. For example, the optical fibers 1a and 1b may be any well-known silica-based optical fiber or plastic fiber. In addition, the present invention can be applied to the optical fibers 1a and 1b of any type, such as a single mode fiber, a multimode fiber, a polarization-maintaining fiber, a photonic crystal fiber, or a multicore fiber.

[0045] In addition, in the portion exposed to the outside of the ferrules 20a and 20b, the optical fibers 1a and 1b may be covered with a known resin coating made of, for example, acrylic, epoxy, silicone, polyimide, etc., and the resin coating may be covered with a silicone tube or a nylon coating, etc., in two or more layers. Also, a polymer waveguide may be used instead of the optical fibers 1a and 1b.

[0046] The material of the ferrules 20a and 20b may be any of general-purpose plastics, engineering plastics, super engineering plastics, and the like, which are often used for MT ferrules.

[0047] Also, a glass material may be used with the same structure as the ferrules 20a and 20b, or a processed product based on a semiconductor material such as silicon, a ceramic material, or the like may be used. For example, like a known optical fiber array, the optical fibers 1a and 1b may be fixed by sandwiching them between a glass block with a V-groove and a lid component. A ferrule made of a glass material and equipped with a positioning structure may be realized by positioning and bonding two guide pins or the like to the glass block and the lid component.

[0048] The outer shapes of the ferrules 20a and 20b and the magnetic structures 22a, 22b, 40, and 41 may be different from those shown in Figures 1A, 1B, 2, 3A, 3B, 4A, 4B, 5A, and 5B. If necessary, the ferrules 20a and 20b and the magnetic structures 22a, 22b, 40, and 41 may be subjected to processing such as chamfering or filleting. These processing methods may be applied to other embodiments.

[0049] The eight optical fibers 1a and 1b are arranged at a pitch of, for example, about 250 μm. Of course, the pitch and number of fibers of the optical fibers 1a and 1b are arbitrary, and any number of fibers such as 2, 4, 8, 12, 16, 24, or 32 can be used. In addition, some of the optical fibers 1a and 1b may be polarization maintaining fibers.

[0050] In addition, the guide pin 3 may be fixed to either one of the ferrules 20a and 20b in order to prevent the guide pin 3 from falling off. The fixing method may include a method of fixing using another part, or a method of using a bonding material, an adhesive, or the like. If necessary, the openings of the guide pin holes 23a and 23b, the openings of the micro holes for the fibers in the ferrules 20a and 20b, and the tips of the guide pins 3 may be tapered to facilitate insertion.

[0051] In this embodiment, the alignment structure is a structure using the guide pin 3 and the guide pin holes 23a, 23b used in MT ferrules, but an alignment structure other than that of this embodiment may be used. For example, a protrusion may be formed on the connection end surface of one of the ferrules 20a, 20b, and a guide groove that fits with the protrusion may be provided on the other connection end surface.

[0052] In this embodiment, the facing connection end faces of the ferrules 20a, 20b, the facing connection end faces of the optical fibers 1a, 1b, and the facing connection end faces of the magnetic structures 22a, 22b are perpendicular to the Z-axis direction, but the connection end faces of the ferrules 20a, 20b and the connection end faces of the optical fibers 1a, 1b may be inclined at an angle of, for example, 8° with respect to the XY plane perpendicular to the Z-axis direction. By making the end faces inclined, recombination of reflected back light into the fiber core hardly occurs.

[0053] The connection end faces of the magnetic structures 22a and 22b may also be inclined with respect to the XY plane perpendicular to the Z-axis direction so as to be approximately parallel to the connection end faces of the ferrules 20a and 20b and the connection end faces of the optical fibers 1a and 1b. The end faces of the magnetic structures 40 and 41 may also be inclined in the same manner.

[0054] In addition, in this embodiment, an example has been described in which the connection end faces of the magnetic structures 22a, 22b and the connection end faces of the ferrules 20a, 20b are aligned on the same plane, or the connection end faces of the ferrules 20a, 20b are positioned so as to protrude relative to the connection end faces of the magnetic structures 22a, 22b, but of course this is not limited to the above.

[0055] A modified example of this embodiment is shown in Figures 6A and 6B. In the example of Figure 6A, the connection end faces of the ferrules 20a, 20b are positioned so as to be slightly recessed from the connection end faces of the magnetic structures 22a, 22b, and a small gap is provided between the optical fibers 1a, 1b while the opposing magnetic structures 22a, 22b are in contact with each other.

[0056] 6B, the connection end faces of the ferrules 20a and 20b are positioned to slightly protrude from the connection end faces of the magnetic structures 22a and 22b, but a spacer part 25 is disposed between the ferrules 20a and 20b to provide a gap between the optical fibers 1a and 1b. The optical fibers 1a and 1b are optically connected via two microlenses 26. Alternatively, the ferrule 20a may be positioned to be recessed from the connection end face of one magnetic structure 22a, and the ferrule 20b may be positioned to protrude from the connection end face of the other magnetic structure 22b, and the depth of the recess in the ferrule 20a and the length of the protrusion of the ferrule 20b may be appropriately set to realize a PC connection.

[0057] Next, a method for joining the ferrules 20a, 20b and the magnetic structures 22a, 22b will be described. As described above, the ferrules 20a, 20b and the magnetic structures 22a, 22b are integrated by any joining method such as adhesion, mechanical fitting, metal joining (solder, etc.). It is preferable to provide a positioning structure to determine the positional relationship between the ferrules 20a, 20b and the magnetic structures 22a, 22b.

[0058] For example, in the example of Fig. 7A, a protrusion 27 is provided on the magnetic structure 22a, and a groove 28 into which the protrusion 27 fits is provided on the ferrule 20a. The protrusion 27 and the groove 28 form a positioning structure. Conversely, in the examples of Fig. 7B and 7C, a protrusion 29 is provided on the ferrule 20a, and a groove 30 into which the protrusion 29 fits is provided on the magnetic structure 22a. The protrusion 29 and the groove 30 form a positioning structure.

[0059] In this way, by providing the positioning structures on the ferrule 20a and the magnetic structure 22a, it is possible to ensure the accuracy of positioning the ferrule 20a and the magnetic structure 22a in the Z-axis direction. Also, by providing a groove on the ferrule 20a or the magnetic structure 22a, it is possible to increase the fixing strength between the ferrule 20a and the magnetic structure 22a when a magnetic force or an insertion / removal force is applied from the outside.

[0060] Another modified example of this embodiment is shown in Figures 8A, 8B, and 8C. In the example of Figures 8A and 8B, a groove 31 (positioning structure) is formed in advance on the outer periphery of the connection end face of the ferrule 20b, and the magnetic structure 22b is fitted into the groove 31. Figure 8A shows a case where the connection end face of the magnetic structure 22b is perpendicular to the Z-axis direction, and Figure 8B shows a case where the connection end face of the magnetic structure 22b is inclined with respect to the XY plane perpendicular to the Z-axis direction.

[0061] Thus, similar to the case of the ferrule 20a, by providing a positioning structure in the ferrule 20b, the positioning accuracy in the Z-axis direction of the ferrule 20b and the magnetic structure 22b can be ensured, and the fixing strength between the ferrule 20b and the magnetic structure 22b can be increased.

[0062] In the example of Fig. 8C, the ferrule 20b and the magnetic structure 22b are integrated by an insert molding technique in which the magnetic structure 22b is embedded during molding of the ferrule 20b. Note that the cross section of Fig. 8C is one example, and the cross-sectional shape after insert molding is not limited to this.

[0063] 9A to 9D show another modified example of this embodiment. In the example of Fig. 9A, protrusions 43 are provided at two locations, top and bottom, of the ferrule 20b. In the example of Fig. 9B, magnetic structures 40, 41 having grooves 45, 46 into which the protrusions 43 fit are formed are attached to the ferrule 20b. The protrusions 43 and the grooves 45, 46 form a positioning structure that determines the positional relationship between the ferrule 20b and the magnetic structures 40, 41.

[0064] In the example of Fig. 9C, protrusions 44 are provided at four positions on the top and bottom of the ferrule 20b. In the example of Fig. 9D, magnetic structures 40, 41 having grooves 47, 48 that fit with the protrusions 44 are attached to the ferrule 20b. The protrusions 44 and the grooves 47, 48 form a positioning structure that determines the positional relationship between the ferrule 20b and the magnetic structures 40, 41.

[0065] In the configuration shown in FIG. 9A to FIG. 9D, the magnetic structure 22b is not provided on the ferrule 20b, so the magnetic structures 40, 41 become the second magnetic structure that is connected to the magnetic structure 22a (first magnetic structure) integrated with the ferrule 20a. There is no need to fix the magnetic structures 40, 41 to the ferrule 20b. The magnetic structures 40, 41 may be fitted to the ferrule 20b after the ferrules 20a and 20b are connected. By configuring the magnetic structures 40, 41 to be attached later, there is no need to be concerned about the magnetic attractive force between the magnetic structure 22a and the magnetic structures 40, 41 when connecting the ferrules 20a and 20b, so that the workability during connection can be improved. As described above, the magnetic structures 40, 41 may be a combination of two or more hard magnetic materials instead of a combination of two half-split structures.

[0066] [Second Example] Fig. 10A is a perspective view of a multi-core optical connector connection structure according to a second embodiment of the present invention before ferrule connection, Fig. 10B is a perspective view of the multi-core optical connector connection structure after ferrule connection, and Fig. 11 is a perspective view of the multi-core optical connector connection structure with a magnet attached after ferrule connection.

[0067] The multi-core optical connector connection structure of this embodiment is composed of an optical connector 6a attached to the ends of multiple optical fibers 5a, an optical connector 6b attached to the ends of multiple optical fibers 5b, and a guide pin 3 that connects the ferrules of the optical connectors 6a, 6b.

[0068] The optical connector 6a is composed of a ferrule 60a (first alignment part) attached to the tip of the optical fiber 5a, a boot 61a that bundles the optical fiber 5a, and a magnetic structure 62a (first magnetic structure) attached around the ferrule 60a. Similarly, the optical connector 6b is composed of a ferrule 60b (second alignment part) attached to the tip of the optical fiber 5b, a boot 61b that bundles the optical fiber 5b, and magnetic structures 62b, 63b (second magnetic structures) attached around the ferrule 60b.

[0069] The optical fibers 5a and 5b are eight-core quartz-based single-mode fibers similar to the optical fibers 1a and 1b. The ferrules 60a and 60b are multi-core ferrules similar to the ferrules 20a and 20b. The optical fibers 5a and 5b are positioned so as to slightly protrude from the connection end faces of the ferrules 60a and 60b, respectively, and the connection end faces of the optical fibers 5a and 5b are polished.

[0070] The connection end face 64a of the magnetic structure 62a and the connection end face of the ferrule 60a are positioned to be aligned on the same plane, but the connection end face of the ferrule 60a may be positioned to protrude relative to the connection end face 64a of the magnetic structure 62a. Similarly, the connection end faces 64b, 65b of the magnetic structures 62b, 63b and the connection end face of the ferrule 60b are positioned to be aligned on the same plane, but the connection end face of the ferrule 60b may be positioned to protrude relative to the connection end faces 64b, 65b of the magnetic structures 62b, 63b.

[0071] In this embodiment, the connection end faces of the ferrules 60a, 60b and the connection end faces of the optical fibers 5a, 5b are inclined at, for example, 8° with respect to the XY plane perpendicular to the longitudinal direction (Z-axis direction) of the optical fibers 5a, 5b.

[0072] A connection end face 64a of the magnetic structure 62a facing the magnetic structures 62b and 63b is inclined at 8° with respect to the XY plane perpendicular to the Z-axis direction so as to be approximately parallel to the connection end face of the ferrule 60a integrated with the magnetic structure 62a and the connection end face of the optical fiber 5a. Similarly, connection end faces 64b and 65b of the magnetic structures 62b and 63b facing the magnetic structure 62a are inclined at 8° with respect to the XY plane so as to be approximately parallel to the connection end face of the ferrule 60b integrated with the magnetic structures 62b and 63b and the connection end face of the optical fiber 5b.

[0073] The magnetic structures 62b and 63b are set to have shorter lengths in the Z-axis direction than the magnetic structure 62a and the ferrules 60a and 60b. In this embodiment, as shown in FIG. 10A, one guide pin 3 is inserted into each of the two guide pin holes of the ferrule 60b of the optical connector 6b, and these guide pins 3 are inserted into the guide pin holes of the ferrule 60a of the optical connector 6a, so that the connection end faces of the ferrules 60a, 60b are butted together and the connection end faces of the optical fibers 5a, 5b are butted together, thereby connecting the optical connectors 6a and 6b.

[0074] The magnetic structures 62a, 62b, and 63b are all made of a soft magnetic material. The ferrules 60a and 60b and the magnetic structures 62a, 62b, and 63b may be joined by any of adhesion, mechanical fitting, and metal joining (soldering, etc.).

[0075] In this embodiment, magnetic structures 70 and 71 (third magnetic structures) are arranged on the end face side opposite to the connection end faces 64b and 65b of the magnetic structures 62b and 63b. The end faces of the magnetic structures 70 and 71 are inclined by 8° with respect to the XY plane perpendicular to the Z-axis direction so as to be approximately parallel to the end faces of the magnetic structures 62b and 63b.

[0076] The magnetic structures 70 and 71 are made of a hard magnetic material (so-called magnets). The magnetization directions of the north and south poles of the magnetic structures 70 and 71 are set along the Z-axis direction. As in the first embodiment, the magnetic structures 70 and 71 are each made of a hard magnetic material having a half-split structure obtained by splitting a square tube in half. By combining the magnetic structures 70 and 71 to form a square tube shape, a part of the ferrule 60b can be accommodated inside the tube. As described above, the magnetization directions of the north and south poles of the magnetic structures 70 and 71 are set along the Z-axis direction, but the magnetization directions of the north and south poles are set to be opposite to each other so that they are integrated by magnetic attraction. For example, the magnetization direction of the magnetic structure 70 is set so that the south pole is in the order of north pole and north pole along the Z-axis direction from the magnetic structures 62b and 63b side, while the magnetization direction of the magnetic structure 71 is set so that the north pole is in the order of south pole and south pole along the Z-axis direction from the magnetic structures 62b and 63b side.

[0077] The difference from the first embodiment is that the second magnetic structure integrated with the ferrule 60b is divided into two. The magnetic structures 62b and 63b are each made of a soft magnetic material and have a half structure formed by splitting a rectangular tube in half. The magnetic structures 62b and 63b are combined to form a rectangular tube shape, so that the magnetic structures 62b and 63b surround the connection end face of the ferrule 60b.

[0078] However, as shown in Figures 10A, 10B, and 11, when integrated with the ferrule 60b, the two magnetic structures 62b and 63b are spaced apart from each other without contacting each other, and therefore a gap 66 filled with air is formed between the magnetic structures 62b and 63b.

[0079] In this embodiment, similarly to the first embodiment, the connection end faces of the ferrules 60a, 60b can be attached and detached from each other and the magnetic structures 70, 71 can be attached and detached in separate steps, so that the optical connectors 6a, 6b can be easily attached and detached. When disconnecting the optical connectors 6a, 6b, the magnetic structures 70, 71 are removed, and then the connection between the ferrules 60a, 60b can be disconnected. This allows the connection to be disconnected with a small force, and improves the workability when disconnecting.

[0080] In addition, in this embodiment, by adopting a configuration in which the magnetic structures 70 and 71 are attached later, there is no need to be concerned about the magnetic attractive force between the magnetic structures 62a and 62b and 63b when connecting the ferrules 60a and 60b, and therefore workability during connection can be improved. The magnetic structures 70 and 71 are attached after the connection of the ferrules 60a and 60b, but since they are not attached at the same time as the connection of the ferrules 60a and 60b, it is possible to easily prevent a sudden collision between the magnetic structures 62b and 63b and the magnetic structures 70 and 71 by using a jig or the ring parts described above.

[0081] Furthermore, in this embodiment, even if chipped powder of the magnetic structures 70, 71 occurs, it is unlikely that the powder will adhere to the connection end faces of the ferrules 60a, 60b after the connection between the ferrules 60a and 60b is completed, and the optical characteristics are unlikely to deteriorate.

[0082] Furthermore, in this embodiment, by providing a gap 66 between the magnetic structures 62b and 63b, the magnetic attractive force acting between the magnetic structures 62a and 62b, 63b can be strengthened. The reason why the magnetic attractive force is increased will be described in detail below.

[0083] Normally, magnetic attraction acts between a hard magnetic material and a soft magnetic material. The magnetic attraction is stronger when the magnetic structure 62a made of a soft magnetic material and the magnetic structures 70, 71 made of a hard magnetic material are directly attached to each other. On the other hand, in this embodiment, the thin magnetic structures 62b, 63b made of a soft magnetic material are present between the magnetic structure 62a and the magnetic structures 70, 71, so the magnetic attraction is weakened. In general, the longer the magnetic structures 62b, 63b are, the weaker the magnetic attraction is, so it was necessary to set the length of the magnetic structures 62b, 63b in the Z-axis direction as short as possible.

[0084] The reason why the magnetic attractive force is reduced will be explained with reference to Fig. 12A. Fig. 12A is a cross-sectional view showing magnetic flux density vectors when there is no gap between the magnetic structures 62b and 63b. When there is no gap between the magnetic structures 62b and 63b, the magnetic circuit loop is closed in the magnetic structures 62b and 63b as shown in Fig. 12A. This results in a reduction in the magnetic attractive force between the magnetic structure 62a and the magnetic structures 62b and 63b.

[0085] On the other hand, Fig. 12B is a cross-sectional view showing magnetic flux density vectors when a gap 66 is provided between the magnetic structures 62b and 63b as in this embodiment. By providing the gap 66 filled with air between the magnetic structures 62b and 63b, as shown in Fig. 12B, the loop of the magnetic circuit returns from the magnetic structures 70 and 62b to the magnetic structures 63b and 71 via the magnetic structure 62a. Therefore, in this embodiment, the magnetic attractive force acting between the magnetic structures 62a and 62b and 63b can be strengthened.

[0086] 12B, it is necessary to provide the gap 66 at a position near the connection between the two halved magnetic structures 70 and 71. In fact, a simulation also confirmed that, according to the configuration of this embodiment, by providing the gap 66 with a width of 0.4 mm, it is possible to prevent a decrease in the magnetic attractive force compared to the case where there is no gap 66.

[0087] As described above, in this embodiment, the ease of attaching and detaching the optical connectors 6a, 6b is improved, and the reduction in the magnetic attraction between the magnetic structure 62a and the magnetic structures 62b, 63b is minimized, thereby realizing an optical connector connection structure that exerts a sufficient pressing force between the connection end faces of the ferrules 60a, 60b.

[0088] 10A, 10B, 11, 12A, and 12B show examples in which the connection parts between the gap 66 and the magnetic structures 70 and 71 are provided on the upper and lower surfaces (XZ plane) of the ferrule 60b, but the connection parts between the gap 66 and the magnetic structures 70 and 71 may be provided at any position. For example, the connection parts between the gap 66 and the magnetic structures 70 and 71 may be provided on both side surfaces (YZ plane sides) of the ferrule 60b.

[0089] Also, the gap 66 may be filled with a non-magnetic material instead of air. Also, instead of the two halves of the magnetic structures 62b, 63b, the magnetic structures 62b, 63b may be a combination of two or more soft magnetic materials that are spaced apart from each other via gaps filled with air or a non-magnetic material and are arranged around the ferrule 60b.

[0090] [Third Example] Fig. 13A is a perspective view of a multi-core optical connector connection structure according to a third embodiment of the present invention before ferrule connection, Fig. 13B is a perspective view of the multi-core optical connector connection structure after ferrule connection, and Fig. 14 is a perspective view of the multi-core optical connector connection structure with a magnet attached after ferrule connection.

[0091] The optical connectors 6a and 6b have the same configuration as that of the second embodiment. The difference from the second embodiment is that after the magnetic structures 70 and 71 are attached as described above, magnetic structures 80 and 81 (fourth magnetic structures) are further attached to the end faces of the magnetic structures 70 and 71 opposite to the connection end faces with the magnetic structures 62b and 63b. The end faces of the magnetic structures 80 and 81 are inclined by 8° with respect to the XY plane perpendicular to the longitudinal direction (Z-axis direction) of the optical fibers 5a and 5b so as to be approximately parallel to the end faces of the magnetic structures 70 and 71.

[0092] The magnetic structures 80 and 81 are made of a soft magnetic material and function as a so-called yoke. Like the magnetic structures 70 and 71, the magnetic structures 80 and 81 are made of a soft magnetic material and have a half structure obtained by splitting a square tube in half. By combining the magnetic structures 80 and 81 into a square tube shape, the magnetic structures 80 and 81 surround the end face of the ferrule 60b on the boot 61b side. By making the magnetic structures 80 and 81 into two half structures, it becomes possible to install the magnetic structures 80 and 81 after installing the magnetic structures 70 and 71.

[0093] The fourth magnetic structure may be made of a soft magnetic material in a rectangular tube shape instead of the two halves of the soft magnetic material. In this case, if the optical fiber 5b is prepared in advance so as to be inserted inside the tube of the fourth magnetic structure, it becomes possible to attach the fourth magnetic structure after the magnetic structures 70 and 71 are attached.

[0094] Furthermore, when the fourth magnetic structure is made of a soft magnetic material having a two-half structure as in this embodiment, changing the connection position of magnetic structures 70 and 71 from the connection position of magnetic structures 80 and 81 can suppress a decrease in the magnetic attraction between magnetic structure 62a and magnetic structures 62b, 63b.

[0095] 14, in a configuration in which the magnetic structures 70 and 71 face each other across the YZ plane, the magnetic structures 80 and 81 may face each other across the XZ plane. Conversely, in a configuration in which the magnetic structures 70 and 71 face each other across the XZ plane, the magnetic structures 80 and 81 may face each other across the YZ plane. In this way, by changing the connection position of the magnetic structures 70 and 71 and the connection position of the magnetic structures 80 and 81, the loop of the magnetic circuit can be efficiently enclosed.

[0096] In this embodiment, the connection end faces of the ferrules 60a, 60b can be attached and detached in separate steps from the magnetic structures 70, 71, 80, 81, making it easy to attach and detach the optical connectors 6a, 6b. When disconnecting the optical connectors 6a, 6b, the magnetic structures 70, 71 are removed first, and then the ferrules 60a, 60b can be disconnected. This allows the connection to be disconnected with a small force, improving the workability when disconnecting.

[0097] In addition, in this embodiment, by adopting a configuration in which the magnetic structures 70 and 71 are attached later, there is no need to be concerned about the magnetic attractive force between the magnetic structures 62a and 62b and 63b when connecting the ferrules 60a and 60b, and therefore workability during connection can be improved. The magnetic structures 70 and 71 are attached after the connection of the ferrules 60a and 60b, but since they are not attached at the same time as the connection of the ferrules 60a and 60b, it is possible to easily prevent a sudden collision between the magnetic structures 62b and 63b and the magnetic structures 70 and 71 by using a jig or the ring parts described above.

[0098] Furthermore, in this embodiment, even if chipped powder of the magnetic structures 70, 71 occurs, it is unlikely that the powder will adhere to the connection end faces of the ferrules 60a, 60b after the connection between the ferrules 60a and 60b is completed, and the optical characteristics are unlikely to deteriorate.

[0099] Furthermore, in this embodiment, the magnetic structures 80 and 81 functioning as yokes are attached to strengthen the confinement of the magnetic circuit, and the magnetic attraction between the magnetic structures 62a and the magnetic structures 62b and 63b can be increased. As a result, in this embodiment, the workability of attaching and detaching the optical connectors 6a and 6b can be improved, and a sufficient pressing force can be generated between the connecting end faces of the ferrules 60a and 60b.

[0100] In the second and third embodiments, similarly to the first embodiment, the connection end faces of the ferrules 60a, 60b, the connection end faces of the optical fibers 5a, 5b, and the end faces of the magnetic structures 62a, 62b, 63b, 70, 71, 80, 81 may be perpendicular to the Z-axis direction. Alternatively, the connection end faces of the ferrules 60a, 60b and the connection end faces of the optical fibers 5a, 5b may be inclined with respect to the XY plane, and the end faces of the magnetic structures 62a, 62b, 63b, 70, 71, 80, 81 may be perpendicular to the Z-axis direction.

[0101] In addition, in this embodiment, the magnetic structures 80, 81 may be a combination of two or more soft magnetic materials instead of a two-half structure, and a cylindrical fourth magnetic structure combining these soft magnetic materials may be attached around the ferrule 60b.

[0102] [Fourth Example] Fig. 15A is a perspective view of a multi-core optical connector connection structure according to a fourth embodiment of the present invention before ferrule connection, Fig. 15B is a perspective view of the multi-core optical connector connection structure after ferrule connection, and Fig. 16 is a perspective view of the multi-core optical connector connection structure with a magnet attached after ferrule connection.

[0103] The multi-core optical connector connection structure of this embodiment is composed of an optical connector 9a attached to the ends of multiple optical fibers 5a, an optical connector 9b attached to the ends of multiple optical fibers 5b, and a guide pin 3 that connects the ferrules of the optical connectors 9a, 9b.

[0104] The optical connector 9a is composed of a ferrule 60a (first alignment part) attached to the tip of the optical fiber 5a, a boot 61a that bundles the optical fiber 5a, and a magnetic structure 90a (first magnetic structure) attached to the periphery of the ferrule 60a. Similarly, the optical connector 9b is composed of a ferrule 60b (second alignment part) attached to the tip of the optical fiber 5b, a boot 61b that bundles the optical fiber 5b, and a magnetic structure 90b (second magnetic structure) attached to the periphery of the ferrule 60b.

[0105] The magnetic structures 90a, 90b integrated with the ferrules 60a, 60b have approximately the same length along the longitudinal direction (Z-axis direction) of the optical fibers 1a, 1b. A connection end face 91a of the magnetic structure 90a facing the magnetic structure 90b is inclined at 8° with respect to the XY plane perpendicular to the Z-axis direction so as to be approximately parallel to the connection end face of the ferrule 60a integrated with the magnetic structure 90a and the connection end face of the optical fiber 5a. Similarly, a connection end face 91b of the magnetic structure 90b facing the magnetic structure 90a is inclined at 8° with respect to the XY plane so as to be approximately parallel to the connection end face of the ferrule 60b integrated with the magnetic structure 90b and the connection end face of the optical fiber 5b.

[0106] The connecting end face of the ferrule 60a is positioned so as to protrude relative to the connecting end face 91a of the magnetic structure 90a, and similarly, the connecting end face of the ferrule 60b is positioned so as to protrude relative to the connecting end face 91b of the magnetic structure 90b. Both of the magnetic structures 90a and 90b are made of a soft magnetic material such as SUS403.

[0107] The difference from the first to third embodiments is that magnetic structures 100, 101 (third magnetic structure) are disposed between the magnetic structures 90a and 90b. Both connection end faces of the magnetic structures 100, 101 facing the magnetic structures 90a, 90b are inclined by 8° with respect to the XY plane perpendicular to the Z-axis direction so as to be approximately parallel to the connection end faces 91a, 91b of the magnetic structures 90a, 90b.

[0108] The magnetic structures 100 and 101 are made of a hard magnetic material (so-called magnet). The magnetization directions of the north and south poles of the magnetic structures 100 and 101 are set along the Z-axis direction. The magnetic structures 100 and 101 are each made of a hard magnetic material having a half-split structure obtained by splitting a square tube in half. The magnetic structures 100 and 101 are combined to form a square tube shape, so that the connection end surfaces of the ferrules 60a and 60b can be accommodated inside the tube. As described above, the magnetization directions of the N and S poles of the magnetic structures 100 and 101 are set along the Z-axis direction, but the magnetization directions of the N and S poles are set to be opposite to each other so that they are integrated by magnetic attraction. For example, the magnetization direction of the magnetic structure 100 is set so that the S pole is in the order of N pole along the Z-axis direction from the magnetic structure 90a side, while the magnetization direction of the magnetic structure 101 is set so that the N pole is in the order of S pole along the Z-axis direction from the magnetic structure 90a side.

[0109] There is no need to fix the magnetic structures 100 and 101 to the ferrules 60a and 60b. After the ferrules 60a and 60b are connected, the magnetic structures 100 and 101 are attached later, so that a magnetic attractive force can be generated between the magnetic structures 90a and 90b.

[0110] When disconnecting the optical connectors 9a and 9b, the magnetic attraction between the magnetic structures 90a and 90b can be eliminated by removing the magnetic structures 100, 101, so that the connection between the ferrules 60a and 60b can be easily disconnected, and the optical connectors 9a and 9b can be easily attached and detached.

[0111] In order to insert the magnetic structures 100 and 101, it is necessary to set the length of the magnetic structure 90b shorter than the distance between the magnetic structures 90a and 90b. Due to mechanical tolerances, etc., a slight gap will be generated between the magnetic structures 90a and 100, 101 or between the magnetic structures 90b and 100, 101, and the gap can be a factor in reducing the magnetic attractive force.

[0112] Therefore, a soft magnetic material such as a magnetic metal foil may be added between the magnetic structures 90a and 100, 101 or between the magnetic structures 90b and 100, 101. By adding a soft magnetic material, it is possible to suppress the decrease in the magnetic attractive force.

[0113] In this embodiment, the connection end faces of the ferrules 60a, 60b can be attached and detached from each other in separate steps, and the magnetic structures 100, 101 can be attached and detached in separate steps, making it easy to attach and detach the optical connectors 9a, 9b. When disconnecting the optical connectors 9a and 9b, the magnetic structures 100, 101 are removed, and then the connection between the ferrules 60a and 60b can be disconnected. This allows the connection to be disconnected with a small force, improving the ease of use when disconnecting.

[0114] In addition, in this embodiment, by adopting a configuration in which the magnetic structures 100 and 101 are attached later, there is no need to be concerned about the magnetic attractive force between the magnetic structures 90a and 90b when connecting the ferrules 60a and 60b, and therefore workability during connection can be improved. The magnetic structures 100 and 101 are attached after the connection of the ferrules 60a and 60b, but since they are not attached at the same time as the connection of the ferrules 60a and 60b, a sudden collision between the magnetic structures 90a and 90b and the magnetic structures 100 and 101 can be easily prevented by using a jig or the like.

[0115] Furthermore, in this embodiment, even if chipped powder occurs from the magnetic structures 100, 101, it is unlikely that the powder will adhere to the connection end faces of the ferrules 60a, 60b after the connection between the ferrules 60a and 60b is completed, and the optical characteristics are unlikely to deteriorate.

[0116] In this embodiment, similarly to the first embodiment, the connection end faces of the ferrules 60a, 60b, the connection end faces of the optical fibers 5a, 5b, and the end faces of the magnetic structures 90a, 90b, 100, 101 may be perpendicular to the Z-axis direction.

[0117] In addition, in this embodiment, the magnetic structures 100, 101 may be a combination of two or more hard magnetic materials instead of a two-half structure, and a cylindrical third magnetic structure combining these hard magnetic materials may be attached around the connection end faces of the ferrules 60a, 60b.

[0118] Although the first to fourth embodiments have been described above, it goes without saying that the present invention can be applied to any combination of the connection objects, connection structures, connection end faces, positioning structures, magnetic structures, materials and arrangements of various components described in the first to fourth embodiments. [Industrial Applicability]

[0119] The present invention can be applied to techniques for connecting optical connectors. [Explanation of symbols]

[0120] 1a, 1b, 5a, 5b...optical fiber, 2a, 2b, 6a, 6b, 9a, 9b...optical connector, 3...guide pin, 20a, 20b, 60a, 60b...ferrule, 21a, 21b, 61a, 61b...boot, 22a, 22b, 40, 41, 62a, 62b, 63b, 70, 71, 80, 81, 90b, 90b, 100, 101...magnetic structure, 23a, 23b...guide pin hole, 25...spacer part, 26...microlens, 27, 29, 43, 44...protrusion, 28, 30, 45, 46, 47, 48...groove, 66...gap.

Claims

1. a first optical connector attached to a tip of a first optical fiber; a second optical connector attached to a tip of a second optical fiber and connectable to the first optical connector; The first optical connector comprises: a first alignment component configured to secure the first optical fiber; a first magnetic structure integral with the first alignment component; The second optical connector includes: a second alignment component configured to secure the second optical fiber; and a second magnetic structure integral with the second alignment component; the first magnetic structure is made of a soft magnetic material; the second magnetic structure is made of a soft magnetic material and has a length in a longitudinal direction of the optical fiber shorter than that of the first magnetic structure; a third magnetic structure made of a hard magnetic material is disposed on an end surface of the second magnetic structure opposite to an end surface connected to the first magnetic structure; the third magnetic structure is made of two hard magnetic materials; the magnetization directions of the N and S poles of the two hard magnetic materials are set along the longitudinal direction of the first and second optical fibers, and the magnetization directions of the N and S poles of the two hard magnetic materials are set to be opposite to each other; The third magnetic structure, which is a cylindrical structure combining the two hard magnetic materials, is attached around the second alignment component; the second magnetic structure is made of two or more soft magnetic materials, the soft magnetic materials being arranged around the second alignment component in a manner spaced apart from one another via gaps filled with air or a non-magnetic material; An optical connector connection structure, characterized in that the gap is provided at a position near a connection portion of the two hard magnetic materials that constitute the third magnetic structure.

2. A first optical connector attached to a tip of a first optical fiber; a second optical connector attached to a tip of a second optical fiber and connectable to the first optical connector; The first optical connector comprises: a first alignment component configured to secure the first optical fiber; a first magnetic structure integral with the first alignment component; The second optical connector includes: a second alignment component configured to secure the second optical fiber; and a second magnetic structure integral with the second alignment component; the first magnetic structure is made of a soft magnetic material; the second magnetic structure is made of a soft magnetic material and has a length in a longitudinal direction of the optical fiber shorter than that of the first magnetic structure; a third magnetic structure made of a hard magnetic material is disposed on an end surface of the second magnetic structure opposite to an end surface connected to the first magnetic structure; a fourth magnetic structure made of a soft magnetic material is disposed on an end surface of the third magnetic structure opposite to an end surface connected to the second magnetic structure; the third magnetic structure is made of two hard magnetic materials; the magnetization directions of the N and S poles of the two hard magnetic materials are set along the longitudinal direction of the first and second optical fibers, and the magnetization directions of the N and S poles of the two hard magnetic materials are set to be opposite to each other; The third magnetic structure, which is a cylindrical structure combining the two hard magnetic materials, is attached around the second alignment component; The fourth magnetic structure is made of two or more soft magnetic materials, and a cylindrical fourth magnetic structure made of a combination of these soft magnetic materials is attached around the second alignment component; An optical connector connection structure, characterized in that the connection positions of the two hard magnetic materials constituting the third magnetic structure are different from the connection positions of the two or more soft magnetic materials constituting the fourth magnetic structure.

3. 3. The optical connector connection structure according to claim 1, An optical connector connection structure characterized in that the first and second alignment parts and the first and second magnetic structures each have positioning structures for determining the positional relationship between the first alignment part and the first magnetic structure, and the positional relationship between the second alignment part and the second magnetic structure.

4. 3. The optical connector connection structure according to claim 1, 2. An optical connector connection structure, wherein the second magnetic structure is molded integrally with the second alignment component.

Images