Optical fiber ribbon core with optical connection component and method for manufacturing optical fiber ribbon core with optical connection component

Abstract

This optical fiber ribbon core with an optical connection component includes: an intermittently fixed optical fiber ribbon core in which a plurality of optical fibers are intermittently connected by a ribbon material; and an optical connection component provided at an end of the intermittently fixed optical fiber ribbon core. In a longitudinal direction, identification marks are provided at constant intervals on the surface of the intermittently fixed optical fiber ribbon core, and the identification marks and the ribbon material are not disposed in a specific range, which is larger than the interval between the identification marks, from a base end of the optical connection component from which the intermittently fixed optical fiber ribbon core extends.

Description

Optical Fiber Tape Core Wire with Optical Connection Component and Manufacturing Method of Optical Fiber Tape Core Wire with Optical Connection Component

[0001] The present invention relates to an optical fiber tape core wire with an optical connection component and a manufacturing method of an optical fiber tape core wire with an optical connection component. This application claims priority based on Japanese Patent Application No. 2024-228190 filed in Japan on December 25, 2024, and incorporates its content herein by reference.

[0002] Patent Document 1 discloses an optical fiber tape core wire having an identification pattern on the surface of the coating of the optical fiber tape core wire in order to identify each of a plurality of optical fiber tape core wires.

[0003] Japanese Patent Application Laid-Open No. 2007-178883

[0004] In recent years, in optical fiber cords and cables, intermittent fixed optical fiber tape core wires may be used to mount optical fibers at high density. Also, optical fibers having a rotational directionality may be used for intermittent fixed optical fiber tape core wires. Examples of optical fibers having a rotational directionality include multi-core fibers. In an optical fiber having a rotational directionality, rotational centering is performed to stabilize the connection of light. Rotational centering is to adjust the position (phase) of the optical fiber in the rotational direction. For example, when connecting two optical fibers, one optical fiber is rotated to match the phase of the other optical fiber. Hereinafter, rotational centering may be simply referred to as centering.

[0005] Here, in optical fiber cords and cables, in order to identify a plurality of intermittently fixed optical fiber tape core wires that are mounted, an identification mark may be provided on the surface of the intermittently fixed optical fiber tape core wire. There was a possibility that this identification mark would affect the centering accuracy by causing the rotation axis during centering to deviate from the central axis of the optical fiber.

[0006] The present invention has been made in consideration of such circumstances, and an object thereof is to provide an optical fiber tape core wire with an optical connection component and a manufacturing method of an optical fiber tape core wire with an optical connection component that can improve the accuracy of the centering angle of the optical fiber fixed to the optical connection component.

[0007] To solve the above problems, an optical fiber ribbon core with an optical connector component according to Embodiment 1 of the present invention comprises an intermittently fixed optical fiber ribbon core in which a plurality of optical fibers are intermittently connected by a tape material, and an optical connector component provided at the end of the intermittently fixed optical fiber ribbon core, wherein, in the longitudinal direction, identification marks are provided at regular intervals on the surface of the intermittently fixed optical fiber ribbon core, and the identification marks and the tape material are not arranged in a specific range that is larger than the interval between the identification marks, from the base end of the optical connector component from which the intermittently fixed optical fiber ribbon core extends.

[0008] Furthermore, in embodiment 2 of the present invention, in the optical fiber ribbon core with optical connection component of embodiment 1, the specified range is 300 mm or less.

[0009] Furthermore, in embodiment 3 of the present invention, in the optical fiber ribbon core with optical connection components of embodiment 1 or 2, the interval between the identification marks is 150 to 200 mm.

[0010] Furthermore, aspect 4 of the present invention is an optical fiber ribbon core with an optical connection component according to any one of aspects 1 to 3, wherein the optical fiber is a multicore fiber or a polarization-maintaining optical fiber.

[0011] Furthermore, a method for manufacturing an optical fiber ribbon core with an optical connection component according to aspect 5 of the present invention involves preparing an intermittently fixed optical fiber ribbon core in which a plurality of optical fibers are intermittently connected by a tape material and identification marks are provided at regular intervals on the surface in the longitudinal direction, removing at least the identification mark closest to the end of the intermittently fixed optical fiber ribbon core and the tape material closest to the end, performing rotational alignment of the optical fibers, and fixing the rotationally aligned optical fibers to an optical connection component.

[0012] Furthermore, in embodiment 6 of the present invention, in the method for manufacturing an optical fiber ribbon core with optical connection components of embodiment 5, the optical fiber is a multicore fiber, and the rotationally aligned multicore fiber is inserted into the main body of the connector.

[0013] Furthermore, in embodiment 7 of the present invention, in the method for manufacturing an optical fiber ribbon core with optical connection components of embodiment 5, the optical fiber is a polarization-maintaining optical fiber, and the rotationally aligned polarization-maintaining optical fiber is fixed in a groove of a fiber array.

[0014] According to the above-described aspect of the present invention, it is possible to provide an optical fiber ribbon core with an optical connector that can improve the accuracy of the alignment angle of the optical fiber fixed to the optical connector, and a method for manufacturing an optical fiber ribbon core with an optical connector.

[0015] This is a side view of an optical fiber ribbon core with optical connection components according to the first embodiment. This is a cross-sectional view of the core of a multicore fiber. This is a cross-sectional view of the core of a PANDA fiber. This is a perspective view of a fiber array on which optical fibers are mounted. This is a view of the fiber array of Figure 4 from the direction of arrow V.

[0016] The optical fiber ribbon cable 100 with optical connection components according to this embodiment will be described below with reference to the drawings. As shown in Figure 1, the optical fiber ribbon cable 100 with optical connection components comprises an optical fiber ribbon cable 10 having a plurality of optical fibers 20 and an optical connection component 50.

[0017] (Direction Definitions) In this embodiment, the longitudinal direction of the optical fiber ribbon core 100 with optical connection components is simply called the longitudinal direction and is represented by the Z axis in the drawing. One side (the tip side) in the longitudinal direction is called the +Z side, and the opposite side (the base side) is called the -Z side. Also, when viewed from the longitudinal direction, the direction in which the multiple optical fibers 20 are arranged is called the first direction and is represented by the X axis in the drawing. One side in the first direction is called the +X side, and the other side is called the -X side. The first direction and the horizontal direction do not have to coincide. The direction that is perpendicular to both the longitudinal direction and the first direction is called the second direction and is represented by the Y axis in the drawing. One side (the +Y side) in the second direction is called the upward direction, and the other side (the -Y side) is called the downward direction. The second direction Z and the vertical direction do not have to coincide.

[0018] (Optical fiber ribbon cable 10) The optical fiber ribbon cable 10 has a plurality of optical fibers 20 and a tape material 30 that adheres adjacent optical fibers 20 together.

[0019] The optical fiber 20 has a bare fiber 21 (see Figures 2-3) and a covering portion 22. The bare fiber 21 is made of, for example, quartz glass. The covering portion 22 covers the bare fiber 21 and serves to protect it.

[0020] The optical fiber 20 in this embodiment has rotational directionality. In this specification, "having rotational directionality" means that when the optical fiber 20 is rotated around the central axis O, the arrangement of the core 21a or the optical transmission characteristics change with this rotation. In other words, when the optical fiber 20 is rotated, the cross-sectional structure perpendicular to the central axis O changes with that rotation. Here, the cross-sectional structure refers to the distribution of the materials constituting the optical fiber 20, or the refractive index distribution resulting therefrom. Examples of optical fiber 20 include multicore fiber 20a, as well as polarization-maintaining fibers such as PANDA (Polarization-maintaining AND Absorption-reducing) type, bowtie type, and elliptical clad type. The optical fiber 20 is not limited to these, and any optical fiber 20 having rotational directionality can be appropriately changed. Below, specific examples of multicore fiber 20a and PANDA type polarization-maintaining fiber (hereinafter simply referred to as PANDA fiber 20b) will be described. Note that in Figures 2 and 3, only the bare fiber 21 is shown, and the illustration of the coating portion is omitted.

[0021] As shown in Figure 2, the bare fiber 21 of the multicore fiber 20a has multiple (four in the illustrated example) cores 21a and a cladding 21b that covers the cores 21a. The multiple cores 21a are arranged inside the cladding 21b. The refractive index of the cladding 21b is lower than that of the cores 21a. Therefore, in the multicore fiber 20a, light can be confined inside each core 21a. The cross-sectional shape of the cores 21a is circular, and the outer diameters of the multiple cores 21a are equal to each other.

[0022] In this embodiment, the cores 21a are arranged side by side at equal intervals in the A-axis direction and the B-axis direction which is perpendicular to the A-axis direction. The centers of the four cores 21a are all at the same distance from the central axis O. Therefore, the centers of the four cores 21a are in rotationally symmetric positions that are 4 times symmetric with respect to the central axis O. Note that the number of cores 21a in a single multicore fiber 20a is not limited to four, but can be two or more. Also, the arrangement is not limited to the case where the distance from the center of all cores 21a to the central axis O is equal to each other. The arrangement of the cores 21a may be n times symmetric (where n is an integer of 2 or more). In such a multicore fiber 20a, the core 21a implementation density can be increased compared to an optical fiber with only one core, thus enabling high-capacity information transmission.

[0023] ・PANDA fiber 20b As shown in Figure 3, the bare fiber 21 of the PANDA fiber 20b comprises a core 21a, a pair of stress-applying portions 21s arranged at intervals on both sides of the core 21a, and a cladding 21b surrounding the core 21a and the pair of stress-applying portions 21s. The cladding 21b may comprise a plurality of cladding layers with different refractive indices (first cladding layer 21b-1, second cladding layer 21b-2, and third cladding layer 21b-3). The PANDA fiber 20b shown in Figure 3 is twofold symmetric because a pair of stress-applying portions 21s are provided with the core 21a as the center. The polarization-maintaining optical fiber is not limited to the PANDA fiber 20b, and may be an optical fiber having stress-applying portions 21s of various shapes or configurations. The polarization-maintaining optical fiber has polarization-maintaining properties due to the stress-applying section 21s, and such a polarization-maintaining optical fiber ribbon core 100 with optical connection components is used in optical transmission systems and the like when connecting optical devices that have polarization dependence.

[0024] The coating portion 22 of the optical fiber 20 is formed of resin or the like. For example, the material of the coating portion 22 may be a UV-curing resin or the like. The coating portion 22 may be formed from only one layer or from multiple layers. For example, the coating portion 22 has a primary layer provided on the outer surface of the bare fiber 21, a secondary layer provided on the outer surface of the primary layer, and a colored layer 22c provided on the outer surface of the secondary layer. The colored layers 22c of the optical fibers 20 included in the optical fiber ribbon cable 10 are each different colors, and the individual optical fibers 20 in the optical fiber ribbon cable 10 can be identified by the color of the colored layer 22c. In the example shown in Figure 1, in the optical fiber ribbon cable 10, the outermost colored layer 22c of the optical fiber 20 is exposed in the portion where the tape material 30 is not provided.

[0025] (Intermittently Fixed Optical Fiber Ribbon Cable 10) The optical fiber ribbon cable 10 of this embodiment is an intermittently fixed optical fiber ribbon cable 10 having a plurality of connecting sections A1 in which adjacent optical fibers 20 are connected to each other, and unconnected sections A2 in which the optical fibers 20 are not connected to each other. At the connecting section A1, two adjacent optical fibers 20 are bonded in a first direction by a tape material 30. As the tape material 30, a thermosetting resin or a UV-curing resin can be used.

[0026] In the intermittently fixed optical fiber ribbon cable 10, when multiple optical fibers 20 are pulled in a first direction, they spread out in a mesh-like (spiderweb-like) pattern. Specifically, one optical fiber 20 is bonded to the two adjacent optical fibers 20 at different positions in the longitudinal direction by tape material 30 provided at the connecting portion A1. Furthermore, adjacent optical fibers 20 are bonded to each other by the connecting portion A1 at a certain distance in the longitudinal direction.

[0027] In the example shown in Figure 1, the tape material 30 is provided only on the mutually opposing surfaces of the two adjacent optical fibers 20 at the connecting portion A1. However, the example is not limited to this, and for example, the tape material 30 may cover the entire circumference of the two optical fibers 20. In the longitudinal direction, the tape material 30 does not have to be provided at the non-connecting portion A2, or the tape material 30 may be provided on the surface of the individual optical fibers 20 at the non-connecting portion A2. Also, in the example shown in Figure 1, the number of optical fibers 20 in the intermittently fixed optical fiber ribbon cable 10 is four, but the example is not limited to four; two or more are acceptable. Furthermore, in the example shown, the length of the connecting portion A1 is shorter than the length of the non-connecting portion A2 in the longitudinal direction. However, the example is not limited to this, and the length of the connecting portion A1 may be equal to or greater than the length of the non-connecting portion A2.

[0028] (Identification Mark 40) The optical fiber ribbon core 10 of this embodiment has identification marks 40 on its surface. The identification marks 40 are provided on the surface of the optical fiber ribbon core 10 at regular intervals in the longitudinal direction. In other words, in areas where the tape material 30 is not provided, the identification marks 40 are provided on the colored layer 22c, and in areas where the tape material 30 is provided, the identification marks 40 are provided on the tape material 30.

[0029] The pattern of the identification mark 40 corresponds to an identification number used to identify each individual optical fiber ribbon core 10. In the optical fiber ribbon core 10 shown in Figure 1, one set of identification marks 40 has a first mark 41 and a second mark 42 that is longer in the longitudinal direction than the first mark 41. By changing the presence, number, and arrangement of the first mark 41 and second mark 42 in a set of identification marks 40, marks indicating different identification numbers can be created. For example, if a set of identification marks 40 has 1 to 4 first marks 41, it represents optical fiber ribbon core 10 with identification numbers 1 to 4, and if a set of identification marks 40 has 1 second mark 42 and 0 to 4 first marks 41, it can represent optical fiber ribbon core 10 with identification numbers 5 to 9, respectively. Furthermore, the set of identification marks 40 is not limited to the example shown by a combination of the first mark 41 and the second mark 42, and the identification number of the optical fiber ribbon core 10 may be represented by various patterns, characters, or the color of the marks.

[0030] The identification mark 40 is made of ink, thermosetting resin, UV-curing resin, etc., applied periodically to the surface of the optical fiber ribbon core 10. The identification mark 40 is made of, for example, black ink or resin, so that it is visible even on a colored layer 22c such as blue or red. The material and color of the identification mark 40 may be changed as appropriate. For example, the identification mark 40 may be formed by periodically applying ink to the surface of the optical fiber ribbon core 10 using an inkjet device and evaporating the solvent in the ink. Alternatively, the identification mark 40 may be formed by periodically applying uncured resin onto the optical fiber ribbon core 10 and curing the resin by heating or UV irradiation. The identification mark 40 may be provided only on the surface of the optical fiber ribbon core 10 facing the +Y direction. In other words, the identification mark 40 does not need to be provided on the surface of the optical fiber ribbon core 10 facing the -Y direction.

[0031] The identification marks 40 are used to verify the individual identification numbers of multiple optical fiber ribbon cores 10 at a branching point where the optical fiber ribbon cores 10 are exposed from the end of an optical fiber cord or cable. Therefore, the spacing M1 between the identification marks 40 must be set shorter than the longitudinal length of the branching point (i.e., the length to which the optical fiber ribbon cores 10 are exposed from the end of the cord or cable) so that at least one identification mark 40 can be visually confirmed at the branching point when verifying the identification number. For this reason, the spacing M1 between the identification marks 40 is generally set to about 150 to 200 mm.

[0032] Here, the interval M1 between identification marks 40 is the distance between the -Z side end 40a of the +Z side identification mark 40 and the +Z side end 40b of the -Z side identification mark 40, of two sets of identification marks 40 adjacent in the longitudinal direction. If the length of one set of identification marks 40 is the length of the identification mark 40 M2, then the sum of the length M2 of the identification mark 40 and the interval M1 between the identification marks 40 is the length of one period of the identification mark 40. The interval M1 between the identification marks 40 is longer than the length M2 of the identification mark 40. In the example in Figure 1, the length of one period of the identification mark 40 (M1 + M2) is shorter than the length of the connected and unconnected parts of the intermittently fixed optical fiber ribbon core 10 (A1 + A2), but this example is not limited to this example, and the length of one period of the identification mark 40 (M1 + M2) may be equal to or greater than the length of the connected and unconnected parts (A1 + A2).

[0033] (Optical connection component 50) The optical connection component 50 is provided at the tip of the optical fiber ribbon core 10. Examples of the optical connection component 50 include, but are not limited to, a fiber array 50A and an MT ferrule connector 50B. At least the portion of the optical fiber 20 where the covering portion 22 at the tip has been removed and the bare fiber 21 is exposed is fixed to the optical connection component 50. Specific examples of the fiber array 50A and the MT ferrule connector 50B will be described below.

[0034] ・Fiber Array 50A As shown in Figures 4-5, the fiber array 50A includes a main body 51. The main body 51 is rectangular parallelepiped and has grooves 51g extending in the longitudinal direction on its upper surface. When viewed from the longitudinal direction, the grooves 51g are roughly V-shaped. At least a portion of the bare fiber 21 of each optical fiber 20 is housed inside the grooves 51g. The optical fibers 20 are fixed to the grooves 51g by adhesive 51r in a state where they are rotated and centered at a predetermined angle. The fiber array 50A of this embodiment has a plurality of grooves 51g, but the number of grooves 51g only needs to be equal to or greater than the number of optical fibers 20 mounted on the fiber array 50A. The fiber array 50A has a tip portion 50a on the +Z side and a base portion 50b on the -Z side from which a plurality of optical fibers 20 extend. The end faces of the optical fibers 20 may be positioned on the +Z side of the tip portion 50a. The fiber array 50A may also include components other than the main body 51. Optical fibers having a rotational directionality are fixed in a rotationally aligned state within the fiber array 50A. As shown in Figure 5, multicore fibers 20a may be fixed, or PANDA fibers 20b may be fixed. For example, a fiber array 50A with PANDA fibers 20b fixed is suitably used when connecting optical devices having polarization dependence.

[0035] MT Ferrule Connector 50B As shown in Figure 1, the MT ferrule connector 50B (hereinafter also simply referred to as connector 50B) has a main body 51 (ferrule 51), the aforementioned fiber array 50A arranged in the internal space 51s of the main body 51, and guide pins 53. The fiber array 50A arranged inside the connector 50B is the same as the fiber array 50A described above, so a detailed explanation is omitted.

[0036] The main body 51 is rectangular parallelepiped in shape. The main body 51 has optical fiber holes (not shown) extending in the longitudinal direction, into which the tips of optical fibers 20 (bare fibers 21) are inserted. The main body 51 further has a pair of guide pin holes 53p arranged to sandwich the multiple fiber holes in the first direction. The pair of guide pin holes 53p are two holes extending in the longitudinal direction, and the rear ends of the guide pins 53 inserted into the guide pin holes 53p are fixed to the main body 51 at the base end side of the main body 51. Furthermore, the main body 51 has an internal space 51s on the -Z side, and a fiber array 50A is arranged in the internal space 51s. The connector 50B is manufactured by inserting the tips of multiple optical fibers 20, which are fixed to the fiber array 50A in a rotationally centered state, into the ferrule 51. The connector 50B has a tip portion 50a on the +Z side that has a bonding end surface where the end face of the optical fiber 20 is exposed, and a base portion 50b on the -Z side from which a plurality of optical fibers 20 extend.

[0037] In the example shown in Figure 1, a male connector is illustrated in which guide pins 53 are inserted into guide pin holes 53p, but a female connector without guide pins may also be used. Furthermore, the connector 50B may have components other than the main body 51. For example, a boot (not shown) may be provided behind the main body 51. The connector 50B is not limited to an MT ferrule connector 50B, and the main body 51 may be housed in a housing (not shown). Also, the connector may not have a fiber array 50A to which rotationally aligned optical fibers 20 are fixed, but rather the rotationally aligned optical fibers 20 may be fixed to the main body 51. For example, a connector to which a multicore fiber 20a is fixed is suitably used when connecting optical devices that perform high-capacity information transmission.

[0038] (Optical fiber ribbon cable 100 with optical connector) At the tip 50a of the optical fiber ribbon cable 100 with optical connector, the end faces of the multiple optical fibers 20 of the optical fiber ribbon cable 10 are exposed in a rotationally aligned state. Therefore, the optical fiber ribbon cable 100 with optical connector can be optically connected well to the optical fibers of an object to be connected, which are similarly rotationally aligned, by the optical connector 50. In the optical fiber ribbon cable 100 with optical connector in this embodiment, the identification marks 40 and tape material 30 are not arranged in a specific range R that is larger than the interval M1 between the identification marks 40 from the base end 50b of the optical connector 50. The reason why the identification marks 40 and tape material 30 are not arranged in the specific range R will be explained below, along with the manufacturing method of the optical fiber ribbon cable 100 with optical connector.

[0039] (Method for manufacturing optical fiber ribbon cable 100 with optical connector components) The method for manufacturing optical fiber ribbon cable 100 with optical connector components will be described below. Note that the following manufacturing method is merely an example, and other manufacturing methods may be used.

[0040] First, prepare the optical fiber ribbon core 10 (preparation step). For example, expose the optical fiber ribbon core 10 from the end of an optical fiber cord or cable. If multiple optical fiber ribbon cores 10 are mounted on an optical fiber cord or cable, visually check the identification marks 40 and find the end of the optical fiber ribbon core 10 with the identification mark 40 indicating the target identification number.

[0041] Next, at least the identification mark 40 closest to the end of the intermittently fixed optical fiber ribbon core 10 and the tape material 30 closest to the end are removed (removal step). In Figure 1, the positions of the removed identification mark 40d and tape material 30d are shown by dashed lines. For example, the surface of the optical fiber ribbon core 10 is rubbed with a file to remove the tape material 30d and identification mark 40d. A special tool for removing the tape material 30 may be used to remove the tape material 30d and identification mark 40d. As a result, the optical fibers 20 are separated in a specific range R, and the colored layer 22c is exposed.

[0042] Next, the coating portion 22 at the tip of the optical fiber 20 is removed to expose the bare fiber 21 (bare fiber exposure step). Next, the optical fiber 20 is rotationally centered (rotational centering step). With a fiber holding portion (not shown) of the rotational centering mechanism, a portion of the optical fiber 20 behind the exposed bare fiber 21 is gripped or sucked, and the optical fiber 20 is rotated around the central axis O to adjust the rotation angle. That is, the fiber holding portion holds the portion where the colored layer 22c is exposed in the optical fiber 20. While observing the rotation angle of the optical fiber 20 from the side or end face, the optical fiber 20 is rotated to the target angle. The rotation angle of the optical fiber 20 is set according to the posture of the optical fiber of the connection target to which the optical fiber ribbon core wire 100 with an optical connection component is connected. For example, the optical fiber 20 is rotated so that the A-axis direction or B-axis direction of the optical fiber 20 shown in FIGS. 2 to 3 coincides with the first direction or second direction of the optical connection component 50.

[0043] Next, the rotationally centered optical fiber 20 is fixed to the optical connection component 50 (fixing step). For example, the bare fiber 21 of the rotationally centered optical fiber 20 is disposed in the groove 51g of the fiber array 50A and fixed with the adhesive 51r.

[0044] Next, when the optical connection component 50 is the connector 50B, the tip portion of the bare fiber 21 is inserted into the fiber hole, the optical fiber 20 protruding from the tip portion 50a of the connector 50B is cut and polished, and the connector 50B is completed (connector forming step). Through the above steps, the optical fiber ribbon core wire 100 with an optical connection component is manufactured.

[0045] In the rotational alignment process, it is preferable that the part of the optical fiber 20 that the optical fiber holding part of the rotational alignment mechanism contacts the optical fiber 20 does not have identification marks 40 or tape material 30 on its surface. This is because if there are identification marks 40 or tape material 30 on the surface of the optical fiber 20, the outer diameter of the optical fiber 20 may fluctuate radially or uneven thickness may occur. If such unevenness occurs, the rotation center of the optical fiber 20 will deviate from the central axis O during rotational alignment, which may lead to a deterioration in the accuracy of rotational alignment. Furthermore, if there are identification marks 40 or tape material 30 on the surface of the optical fiber 20, the outer diameter of the part that is held by the optical fiber holding part will be larger than the outer diameter of the optical fiber 20 without these foreign objects. Therefore, the optical fiber 20 may not be properly held by the fiber holding part, which may lead to a deterioration in the accuracy of rotational alignment or make it impossible to rotate the optical fiber 20 to the desired rotation angle.

[0046] Typically, the length over which the optical fiber holder contacts the optical fiber 20 is approximately 150 mm in the longitudinal direction. If there are no identification marks 40 or tape material 30 on the outer circumference of the optical fiber 20 at the point where the optical fiber holder contacts the optical fiber 20, it is possible to properly hold the optical fiber 20. However, if there are foreign objects such as identification marks 40 or tape material 30 near the optical fiber holder, or if the connecting part A1 where two optical fibers 20 are connected is near the optical fiber holder, the rotation of the optical fiber 20 may be restricted, making it impossible to rotate the optical fiber 20 to the desired angle. Furthermore, in the rotational alignment process, finding a location on the end of the optical fiber ribbon core 10 where the identification marks 40 and tape material 30 are not positioned so as not to affect the rotational alignment work even when held by the optical fiber holder requires considerable effort and time, which can lead to a decrease in work efficiency.

[0047] Taking these into consideration, in the removal process, at least the identification mark 40 closest to the terminal of the intermittent fixed optical fiber tape core wire 10 and the tape material 30 closest to the terminal are removed. Note that at the terminal of the intermittent fixed optical fiber tape core wire 10, the identification mark 40 at the location closest to the terminal appears at an arbitrary position. Also, the tape material 30 of the intermittent fixed optical fiber tape core wire 10 similarly appears at an arbitrary position. For this reason, when fabricating the branching portion of the optical fiber cord and the cable, the identification mark 40 closest to the terminal may appear at a position equivalent to the tip of the intermittent fixed optical fiber tape core wire 10. Also, the tape material 30 may appear overlapping the rear end of the identification mark 40 closest to the terminal. In such a case, considering the ease of the rotation alignment operation, at least one identification mark 40 closest to the terminal of the intermittent fixed optical fiber tape core wire 10 and the tape material 30 provided on the tip side of the intermittent fixed optical fiber tape core wire 10 rather than the at least one identification mark 40 may be removed. Or, one identification mark 40 closest to the terminal of the intermittent fixed optical fiber tape core wire 10 and the tape material 30 provided on the tip side of the intermittent fixed optical fiber tape core wire 10 rather than the second closest identification mark 40 from the terminal may be removed. Further, the identification mark 40 and the tape material 30 may be removed within the range up to 300 mm backward from the portion that becomes the base end portion 50b of the optical connection component 50.

[0048] Thereby, in the rotation alignment process after the removal process, the optical fiber 20 can be surely rotated to a desired angle, and the working efficiency can be improved. Also, in the optical fiber tape core wire 100 with the fabricated optical connection component, the identification mark 40 and the tape material 30 are not arranged in a specific range R longer than the interval M1 between the identification marks 40 from the portion that becomes the base end portion 50b of the optical connection component 50.

[0049] Here, the specified range R is longer than the interval M1 between the identification marks 40. Furthermore, it is more preferable that the specified range R is 300 mm or less. If the specified range R is less than or equal to the interval M1 between the identification marks 40, the optical fiber holder may not be able to properly hold the optical fiber 20 during rotational alignment, which may worsen the accuracy of rotational alignment. If the specified range R is larger than 300 mm, it takes time to remove the identification marks 40 and tape material 30, which reduces work efficiency. In addition, the area where the identification marks 40 and tape material 30 are not provided becomes longer, making it difficult to confirm the identification number of the optical fiber ribbon core 10, and the longer the section in which the optical fibers 20 are individually separated may lead to a decrease in the handling of the optical fiber bundle.

[0050] As described above, the optical fiber ribbon cable 100 with optical connection components of this embodiment comprises an intermittently fixed optical fiber ribbon cable 10 in which a plurality of optical fibers 20 are intermittently connected by a tape material 30, and an optical connection component 50 provided at the end of the intermittently fixed optical fiber ribbon cable 10. In the longitudinal direction, identification marks 40 are provided at regular intervals on the surface of the intermittently fixed optical fiber ribbon cable 10, and in a specific range R that is larger than the interval M1 between the identification marks 40, the identification marks 40 and the tape material 30 are not arranged from the base end 50b of the optical connection component 50 from which the intermittently fixed optical fiber ribbon cable 10 extends.

[0051] This makes it possible to improve the accuracy of the alignment angle of the optical fiber 20 fixed to the optical connector 50. In addition, it is possible to improve the work efficiency when aligning the optical fiber 20 and fixing it to the optical connector 50.

[0052] Furthermore, the specific range R is 300 mm or less. This prevents a decrease in work efficiency when connecting the optical connection component 50 and a decrease in the handling of the optical fiber bundle near the optical connection component 50.

[0053] Furthermore, the spacing M1 between the identification marks 40 is 150 to 200 mm. This allows the identification marks 40 to be visually confirmed at branching points where the optical fiber ribbon core 10 is exposed from optical fiber cords or cables.

[0054] Furthermore, the optical fiber 20 is either a multicore fiber 20a or a polarization-maintaining optical fiber. In the optical fiber ribbon cable 100 with optical connection components of this embodiment, since these optical fibers 20 having a rotational direction are fixed in a rotationally aligned state, it becomes possible to suitably connect to an object having similarly rotationally aligned optical fibers 20.

[0055] Furthermore, the manufacturing method of the optical fiber ribbon core 100 with optical connection components of this embodiment involves preparing an intermittently fixed optical fiber ribbon core 10 in which a plurality of optical fibers 20 are intermittently connected by a tape material 30, and identification marks 40 are provided at regular intervals on the surface in the longitudinal direction. At least the identification mark 40 closest to the end of the intermittently fixed optical fiber ribbon core 10 and the tape material 30 closest to the end are removed, the optical fibers 20 are rotated and centered, and the rotated and centered optical fibers 20 are fixed to the optical connection component 50.

[0056] This makes it possible to improve the accuracy of the alignment angle of the optical fiber 20 fixed to the optical connector 50. In addition, it is possible to improve the work efficiency when aligning the optical fiber 20 and fixing it to the optical connector 50.

[0057] Furthermore, the optical fiber 20 is a multicore fiber 20a, and the rotationally aligned multicore fiber 20a is inserted into the main body 51 of the connector 50B. This makes it possible to manufacture an optical fiber ribbon 10 having an optical connection component 50 that can suitably connect the multicore fiber 20a.

[0058] Furthermore, the optical fiber 20 is a polarization-maintaining optical fiber, and the rotationally aligned polarization-maintaining optical fiber is fixed in the groove 51g of the fiber array 50A. This makes it possible to manufacture an optical fiber ribbon 10 having an optical connection component 50 that can suitably connect polarization-maintaining optical fibers.

[0059] The technical scope of the present invention is not limited to the embodiments described above, and various modifications can be made without departing from the spirit of the invention.

[0060] For example, the optical fiber 20 having rotational directionality is not limited to an optical fiber 20 that is n-fold symmetric. For example, a marker core with a refractive index different from that of the core 21a and cladding 21b may be provided in the bare fiber 21 at a position that breaks the symmetry. Alternatively, a recess may be provided on the outer surface of the bare fiber 21. In this case, the rotational alignment of the optical fiber 20 may be performed based on the positions of the marker core and the recess.

[0061] Furthermore, without departing from the spirit of the present invention, the components in the above-described embodiments may be replaced with well-known components as appropriate, and the above-described embodiments and modifications may be combined as appropriate.

[0062] 10...Optical fiber ribbon (intermittently fixed optical fiber ribbon), 20...Optical fiber, 20a...Multicore fiber, 20b...PANDA fiber (polarization-maintaining optical fiber), 21...Bare fiber, 30...Tape material, 40...Identification mark, 50...Optical connection component, 50A...Fiber array, 50B...Connector, 50b...Base end, 51...Main body, 51g...Groove, 100...Optical fiber ribbon with optical connection component, M1...Spacing between identification marks, R...Specific range

Claims

1. An optical fiber ribbon core with an optical connector, comprising: an intermittently fixed optical fiber ribbon core in which multiple optical fibers are intermittently connected by a tape material; and an optical connector provided at the end of the intermittently fixed optical fiber ribbon core, wherein, in the longitudinal direction, identification marks are provided at regular intervals on the surface of the intermittently fixed optical fiber ribbon core, and the identification marks and the tape material are not arranged in a specific range greater than the interval between the identification marks from the base end of the optical connector from which the intermittently fixed optical fiber ribbon core extends.

2. The optical fiber ribbon core with optical connection component according to claim 1, wherein the specified range is 300 mm or less.

3. The optical fiber ribbon core with optical connection component according to claim 1 or 2, wherein the interval between the identification marks is 150 to 200 mm.

4. The optical fiber ribbon cable with optical connector according to any one of claims 1 to 3, wherein the optical fiber is a multicore fiber or a polarization-maintaining optical fiber.

5. A method for manufacturing an optical fiber ribbon core with an optical connector, comprising: preparing an intermittently fixed optical fiber ribbon core in which multiple optical fibers are intermittently connected by a tape material and identification marks are provided at regular intervals on the surface in the longitudinal direction; removing at least the identification marks closest to the end of the intermittently fixed optical fiber ribbon core and the tape material closest to the end; performing rotational alignment of the optical fibers; and fixing the rotationally aligned optical fibers to an optical connector.

6. The method for manufacturing an optical fiber ribbon core with an optical connection component according to claim 5, wherein the optical fiber is a multicore fiber, and the rotationally aligned multicore fiber is inserted into the main body of the connector.

7. The method for manufacturing an optical fiber ribbon core with optical connection components according to claim 5, wherein the optical fiber is a polarization-maintaining optical fiber, and the rotationally aligned polarization-maintaining optical fiber is fixed in a groove of a fiber array.

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