JP2019066769A - Optical fiber fusion-splicing method, optical fiber fusion-splicing structure, and optical wiring member - Google Patents

Abstract

To suppress an expansion in intervals between optical fiber ribbons due to fusion-splicing when using two or more optical fiber ribbons stacking one on top of another.SOLUTION: An optical fiber fusion-splicing method involves splicing each other by fusion a first and a second optical fiber ribbon group in which two or more optical fiber ribbons 31, 33, each including a plurality of optical fibers 20 arrayed in one direction, are stacked one on top of another, the method including a step of repeating, as many times as the number of optical fiber ribbons, a first step for fusion-bonding one end of one optical fiber ribbon included in the first optical fiber ribbon group and one end of one optical fiber ribbon included in the second optical fiber ribbon group to each other, and a second step for covering the fusion-spliced parts 31c, 33c formed by fusion-bonding with protective sleeves 31d, 33d. To ensure that the protective sleeves do not overlap each other, the fusion-spliced positions of two or more optical fiber ribbons are shifted from each other.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an optical fiber fusion splice method, an optical fiber fusion splice structure, and an optical wiring member.

  Patent Document 1 describes a multicore optical connector and a method of manufacturing the same.

JP, 2014-013309, A

  With the recent increase in the amount of data communication, the number of optical fibers disposed in one optical transmission path has been steadily increasing. For this reason, so-called optical fiber ribbons are used in which a plurality of (for example, 12 or 16) optical fibers are arranged in one direction and fixed with a resin. Furthermore, it is also considered to use two or more optical fiber ribbons in layers. For example, when drawing optical fibers for the number of cores from a multi-fiber optical connector such as an MT connector, two optical fiber ribbons are overlapped and used if the number of optical fiber arrays of the multi-fiber optical connector is two.

  As described above, even when two or more optical fiber ribbons are overlapped and used, it may be necessary to connect the optical fiber ribbons by fusion. In that case, the resin coating at one end is peeled off for each optical fiber ribbon, and fusion bonding of bare fibers is performed, and the formed fusion connection is covered with a resin protective sleeve. However, in general, the protective sleeve contains a reinforcing member for maintaining the mechanical strength of the bare fiber and a heat melting resin tube, and the protective sleeve becomes much thicker than the optical fiber ribbon. ing. Therefore, when two or more protective sleeves overlap each other, the distance between the optical fiber ribbons increases. Therefore, the miniaturization of the device provided with the two or more optical fiber ribbons is hindered. Also, the other end of the optical fiber tape core is connected to a connection object such as a multi-core optical connector, for example, but if the distance between the optical fiber tape cores in the connection object is set small, the optical fiber tape The center line will be inclined. Therefore, there is a possibility that excessive bending may occur in the optical fiber ribbon at the connection portion with the connection object. Excessive bending of the optical fiber ribbon may increase the bending loss of the optical fibers constituting the optical fiber ribbon and may damage the optical fibers.

  The present invention has been made in view of such problems, and when two or more optical fiber ribbons are overlapped and used, the expansion of the interval between the optical fiber tapes by fusion bonding is suppressed. It is an object of the present invention to provide an optical fiber fusion splice method, an optical fiber fusion splice structure, and an optical wiring member.

  In order to solve the problems described above, a fusion splicing method of optical fibers according to an embodiment is a method in which two or more optical fiber ribbons, each including a plurality of optical fibers arranged in one direction, are overlapped with each other. A method of interconnecting a first optical fiber ribbon and a second optical fiber ribbon by fusion bonding, comprising: one end of one optical fiber ribbon included in the first optical fiber ribbon; A first step of mutually fusing the one end of the optical fiber ribbon included in the optical fiber ribbon, and a second step of covering the fusion spliced portion formed by the fusion with a protective sleeve; , As many as the number of optical fiber ribbons. In this method, the positions of the fusion splices of the two or more optical fiber ribbons are mutually offset so that the protective sleeves do not overlap each other.

  Also, the fusion spliced structure of optical fibers according to one embodiment includes the first and second optical fibers in which two or more optical fiber ribbons, each including a plurality of optical fibers arranged in one direction, are overlapped with each other. A tape core group, one end of each optical fiber core core included in the first optical fiber tape core group, and one end of each optical fiber core core included in the second optical fiber tape core group The two or more fusion spliced parts mutually fused, and two or more protective sleeves which respectively cover the two or more fusion spliced parts. The two or more fusion splices are offset from one another so that the protective sleeves do not overlap one another.

  Moreover, the optical wiring member which concerns on one Embodiment is equipped with several said fusion-bonding structure and the wiring part by which several optical waveguides were wired. A multicore optical connector is attached to the other end of each first optical fiber ribbon. The plurality of optical waveguides have an aggregated end aggregated for each corresponding second optical fiber tape core group. The concentrated end is positioned at the edge of the wiring portion and connected to the other end of the corresponding second optical fiber ribbon.

  According to the fusion splicing method of optical fibers, fusion splicing structure of optical fibers, and optical wiring member according to the present invention, the optical fiber tape by fusion splicing when two or more optical fiber ribbons are overlapped and used It is possible to suppress the expansion of the distance between the cords.

(A) and (b) of FIG. 1 are a plan view and a side sectional view showing a configuration of an optical wiring member according to an embodiment. FIG. 2 is an enlarged view of the optical fiber structure. (A) and (b) of FIG. 3 are a perspective view and a front view respectively showing a specific structural example of the protective sleeve. FIG. 4 is a flowchart showing the fusion splicing method of one embodiment. (A) and (b) of FIG. 5 are a plan view and a cross-sectional view showing the configuration of an optical wiring member as a comparative example. FIG. 6 is an enlarged view of the optical fiber structure. (A) and (b) of FIG. 7 is a figure for demonstrating the other effect by the fusion splicing method of one Embodiment, and the fusion splicing structure.

Description of the embodiment of the present invention
First, the contents of the embodiment of the present invention will be listed and described. A fusion splicing method of optical fibers according to one embodiment includes first and second optical fiber tapes in which two or more optical fiber ribbons, each including a plurality of optical fibers arranged in one direction, are overlapped with each other. A method for interconnecting wire groups by fusion, comprising: one end of one optical fiber ribbon included in a first optical fiber ribbon, and second end included in a second optical fiber ribbon The number of optical fiber ribbons: a first step of mutually fusing the one end of the optical fiber ribbon and a second step of covering the fusion spliced portion formed by the fusion with a protective sleeve Only repeat steps. In this method, the positions of the fusion splices of the two or more optical fiber ribbons are mutually offset so that the protective sleeves do not overlap each other.

  Also, the fusion spliced structure of optical fibers according to one embodiment includes the first and second optical fibers in which two or more optical fiber ribbons, each including a plurality of optical fibers arranged in one direction, are overlapped with each other. A tape core group, one end of each optical fiber core core included in the first optical fiber tape core group, and one end of each optical fiber core core included in the second optical fiber tape core group The two or more fusion spliced parts mutually fused, and two or more protective sleeves which respectively cover the two or more fusion spliced parts. The two or more fusion splices are offset from one another so that the protective sleeves do not overlap one another.

  In the fusion splicing method described above, the positions of the fusion splices of the two or more optical fiber ribbons are mutually shifted so that the protective sleeves do not overlap each other. In the fusion spliced structure described above, the positions of the two or more fusion splices are offset from each other, and the protective sleeves do not overlap each other. Thus, when two or more optical fiber ribbons are overlapped and used, it is possible to suppress the expansion of the interval between the optical fiber ribbons by fusion bonding. Therefore, the apparatus provided with two or more optical fiber ribbons can be miniaturized. In addition, since excessive bending of the optical fiber ribbon at the connection portion with the connection object can be suppressed, bending loss of each optical fiber constituting the optical fiber ribbon can be suppressed, and damage to each optical fiber can be reduced. It can be reduced.

  Moreover, the optical wiring member which concerns on one Embodiment is equipped with several said fusion-bonding structure and the wiring part by which several optical waveguides were wired. A multicore optical connector is attached to the other end of each first optical fiber ribbon. The plurality of optical waveguides have an aggregated end aggregated for each corresponding second optical fiber tape core group. The concentrated end is positioned at the edge of the wiring portion and connected to the other end of the corresponding second optical fiber ribbon. Since this optical wiring member is provided with the fusion spliced structure, it can be miniaturized and light loss can be reduced.

Details of the Embodiment of the Present Invention
The fusion splicing method of the optical fiber, the fusion splicing structure of the optical fiber, and the specific example of the optical wiring member according to the embodiment of the present invention will be described below with reference to the drawings. The present invention is not limited to these exemplifications, but is shown by the claims, and is intended to include all modifications within the meaning and scope equivalent to the claims. In the following description, the same reference numerals are given to the same elements in the description of the drawings, and the redundant description will be omitted.

  (A) and (b) of FIG. 1 are a plan view and a side sectional view showing the configuration of an optical wiring member 1A according to an embodiment. An XYZ orthogonal coordinate system is shown in (a) and (b) of FIG. 1 for easy understanding. FIG. 1A is a plan view seen from the Z direction. Further, (b) of FIG. 1 is a cross-sectional view along the XZ plane. The optical wiring member 1A includes a wiring portion 22, M (M is an integer of 4 or more) optical fiber structures 30A, N (N is an integer of 4 or more) optical fiber structures 30B, and M pieces A multicore optical connector 41 and N multicore optical connectors 42 are provided. The optical fiber structures 30A and 30B are examples of the fusion spliced structure in the present embodiment.

  In the wiring portion 22, a plurality of optical waveguides (optical fibers) 20 are wired. Each of the plurality of optical fibers 20 wired in the wiring portion 22 corresponds to one of the optical fiber structures 30A at one end. The plurality of optical fibers 20 have an aggregation end 23 aggregated at each of the corresponding optical fiber structures 30A. Each of the plurality of optical fibers 20 corresponds to one of the optical fiber structures 30B at the other end. The plurality of optical fibers 20 have, at the other end, an aggregation end 25 aggregated for each corresponding optical fiber structure 30B. The aggregated ends 23, 25 may be taped ends which are taped (ribbed) for each of the corresponding optical fiber structures 30A, 30B. In that case, the plurality of optical fibers 20 are arranged along the Y direction at the aggregation ends 23 and 25.

  In the example shown in FIG. 1, (M × N) optical fibers 20 in the wiring portion 22 are disposed to intersect each other in three dimensions. The optical fiber 20 forms M aggregated end portions 23 in which N optical fibers 20 are aggregated for each corresponding optical fiber structure 30A at each one end side. In addition, the optical fiber 20 forms, at each other end side, N aggregation end portions 25 in which M optical fibers 20 are aggregated for each corresponding optical fiber structure 30B. At each concentration end 23, N optical fibers 20 are arranged along the Y direction. At each concentration end 25, M optical fibers 20 are arranged along the Y direction. Each of the N optical fibers 20 of each aggregation end 23 extends toward each of the N aggregation ends 25. In other words, each of the M optical fibers 20 of each aggregation end 25 extends toward each of the M aggregation ends 23. The wiring form of such an optical fiber 20 may be referred to as shuffled optical wiring.

  The wiring form of the wiring section 22 is not limited to such shuffled optical wiring. The number of (M × N) may be different from the total number of optical fibers 20. The wiring portion 22 can have various wiring configurations between the M aggregation ends 23 and the N aggregation ends 25. Depending on the configuration, a certain aggregation end 23 and a certain aggregation end may be provided. Two or more optical fibers 20 connecting the unit 25 may be taped.

  The aggregated ends 23 and 25 are positioned at the edge of the wiring portion 22. That is, the M aggregation ends 23 are positioned at the edge Sa of the wiring portion 22, and the N aggregation ends 25 are positioned at the edge Sb of the wiring portion 22.

  The M optical fiber structures 30A are arranged to be separated from each other along the Y direction. The proximal end of each optical fiber structure 30A is connected to the corresponding aggregation end 23. A multi-core optical connector 41 is attached to the tip of each of the optical fiber structures 30A. The multicore optical connector 41 is, for example, an MT connector. The multi-core optical connector 41 collectively connects N optical fibers constituting each optical fiber structure 30A. The multicore optical connector 41 is connected to the optical receptacle of the external device to which the optical wiring member 1A is attached.

  FIG. 2 is an enlarged view of the optical fiber structure 30A. Each of the optical fiber structures 30A is composed of two or more fusion spliced optical fiber ribbons. The optical fiber structure 30A of the present embodiment is constituted by the fusion spliced portion-attached optical fiber tape core wire 31 and the fusion spliced portion-attached optical fiber tape core wire 33. Among them, the fusion spliced optical fiber ribbon 31 has optical fiber ribbons 31a and 31b, a fusion splice 31c, and a protective sleeve 31d. The optical fiber ribbon 31a and the optical fiber ribbon 31b are connected to each other through the fusion splice 31c. Also, the fusion spliced optical fiber tape core wire 33 has optical fiber tape core wires 33a and 33b, a fusion spliced portion 33c, and a protective sleeve 33d. The optical fiber ribbon fiber core 33a and the optical fiber tape fiber core wire 33b are connected to each other through the fusion splice 33c.

  Each of the optical fiber ribbons 31a, 31b, 33a, and 33b is solidified with a resin (for example, an ultraviolet curable resin) in a state in which N / 2 optical fibers are arranged in one direction (Y direction). It is ribbonized). The arrangement direction of the optical fibers in the optical fiber ribbons 31 b and 33 b is the same as the arrangement direction of the optical fibers 20 at the concentration end 23.

  The optical fiber ribbons 31a and 33a are superimposed on each other in the Z direction intersecting with both the arrangement direction (Y direction) of the optical fibers and the extension direction (X direction) of the optical fibers. The optical fiber ribbons are composed of The optical fiber ribbons 31b and 33b are also overlapped with each other in the Z direction intersecting with both the arrangement direction (Y direction) of the optical fibers and the extension direction (X direction) of the optical fibers. The two optical fiber ribbons are constructed.

  The fusion spliced portion 31c has one end of the optical fiber ribbon 31A at which the coating resin is peeled off and the bare fiber is exposed and one end of the optical fiber ribbon 31b at which the coating resin is peeled off and the bare fiber is exposed. And are mutually fusion-bonded. The protective sleeve 31 d covers the fusion splice 31 c to protect the bare fiber. The protective sleeve 31d is provided from the surface of the coating resin of the optical fiber ribbon 31a to the surface of the coating resin of the optical fiber ribbon 31b so as to completely cover the bare fibers of the optical fiber ribbon 31a, 31b. Be Similarly, in the fusion splice 33c, one end of the optical fiber ribbon 33a, in which the coating resin is peeled off and the bare fiber is exposed, and the coating resin is peeled off, and the bare fiber is exposed in the optical fiber ribbon 33b. One end is fusion-bonded to one another. The protective sleeve 33d covers the fusion splice 33c to protect the bare fiber. The protective sleeve 33d is provided from the surface of the covering resin of the optical fiber ribbon 33a to the surface of the covering resin of the optical fiber ribbon 33b so as to completely cover the bare fibers of the optical fiber ribbons 33a, 33b. Be

  A multi-core optical connector 41 is attached to the other ends of the optical fiber ribbons 31a and 33a. Also, the other ends of the optical fiber ribbons 31 b and 33 b are connected to the corresponding aggregated end 23.

  (A) and (b) of FIG. 3 are a perspective view and a front view showing a specific structural example of the protective sleeves 31d and 33d, respectively. Referring to (a) and (b) of FIG. 3, the protective sleeves 31d and 33d have a metal reinforcing member 35 extending in the longitudinal direction of the protective sleeves 31d and 33d, and a cross section as a covering member surrounding the reinforcing member 35. And an oval heat-shrinkable tube 36. The reinforcing member 35 defines, in the heat-shrinkable tube 36, a first region 37a and a second region 37b which are disposed with the reinforcing member 35 interposed therebetween. Further, the protective sleeves 31 d and 33 d have one heat melting resin tube 38 having an elliptical cross section disposed in the heat shrinking tube 36, and the first region 37 a is the heat melting resin tube 38. It is covered by The fusion spliced portions 31c and 33c and the bare fiber portions before and after the fusion spliced portions 31c and 33c are accommodated and held in the first region 37a. The reinforcing member 35 is a thin flat plate made of, for example, metal or glass. The thickness of the reinforcing member 35 is, for example, about 0.2 mm to 0.3 mm.

  As shown in FIG. 2, in the present embodiment, the positions of the fusion splices 31c and 33c in the longitudinal direction (X direction) of the optical fiber structure 30A are offset from each other. Specifically, fusion spliced portion 31c is located between fusion spliced portion 33c and concentrated end portion 23 in the X direction, and fusion spliced portion 33c is multi-cored with fusion spliced portion 31c in the X direction. It is located between it and the optical connector 41.

  Further, the protective sleeve 31 d and the protective sleeve 33 d do not overlap with each other (do not interfere with each other) in the stacking direction of the optical fiber ribbons 31 and 33 with the fusion splice portion. Specifically, one end 31e of the protective sleeve 31d on the optical fiber tape core 31a side is located on the side of the collective end 23 with respect to the one end 33e of the protective sleeve 33d on the optical fiber tape core 33b side, and the one end 33e is , One end 31e is located on the multi-core optical connector 41 side. Accordingly, the whole of the protective sleeve 31d overlaps with the optical fiber ribbon 33b, and the whole of the protective sleeve 33d overlaps with the optical fiber ribbon 31a.

  Refer to (a) and (b) of FIG. 1 again. The N optical fiber structures 30B have the same configuration as the M optical fiber structures 30A described above. That is, the N optical fiber structures 30B are disposed in a state of being separated from each other along the Y direction. The proximal end of each optical fiber structure 30 B is connected to the corresponding aggregated end 25. A multicore optical connector 42 is attached to the tip of each optical fiber structure 30B. The multicore optical connector 42 is, for example, an MT connector. The multicore optical connector 42 collectively connects the M optical fibers constituting each of the optical fiber structures 30B. The multicore optical connector 42 is connected to an optical receptacle of an external device to which the optical wiring member 1A is attached.

  Each of the optical fiber structures 30B, like the optical fiber structure 30A, is constituted by two or more fusion spliced optical fiber ribbons. The optical fiber structure 30B of the present embodiment is constituted by the fusion spliced optical fiber tape core wire 32 and the fusion spliced optical fiber tape core wire 34. Among them, the fusion spliced optical fiber ribbon 32 has optical fiber ribbons 32a and 32b, a fusion splice 32c, and a protective sleeve 32d. The optical fiber ribbon 32a and the optical fiber ribbon 32b are connected to each other via the fusion splice 32c. The fusion spliced optical fiber ribbon 34 has optical fiber ribbons 34a and 34b, a fusion splice 34c, and a protective sleeve 34d. The optical fiber ribbon 34a and the optical fiber ribbon 34b are connected to each other through the fusion splice 34c.

  Each of the optical fiber ribbons 32a, 32b, 34a, and 34b is solidified with a resin (for example, an ultraviolet curable resin) in a state in which M / 2 optical fibers are arranged in one direction (Y direction). It is ribbonized). The arrangement direction of the optical fibers in the optical fiber ribbons 32 b and 34 b is the same as the arrangement direction of the optical fibers 20 at the aggregation end 25.

  The optical fiber ribbons 32a and 34a are overlapped with each other in a direction intersecting with both the arrangement direction of the optical fibers (Y direction) and the extension direction of the optical fibers (X direction), and the first in the present embodiment. Configure optical fiber ribbons. The optical fiber ribbons 32b and 34b are also overlapped with each other in a direction intersecting both the arrangement direction (Y direction) of the optical fibers and the extension direction (X direction) of the optical fibers, and the second in the present embodiment The optical fiber ribbons are composed of

  The fusion splice 32c has one end of an optical fiber ribbon 32a with the bare fiber exposed by peeling the coating resin and one end of the optical fiber ribbon 32b with the naked bare fiber exposed. And are mutually fusion-bonded. The protective sleeve 32d covers the fusion splice 32c and protects the bare fiber. The protective sleeve 32d is provided from the surface of the coating resin of the optical fiber ribbon 32a to the surface of the coating resin of the optical fiber ribbon 32b so as to completely cover the bare fibers of the optical fiber ribbons 32a, 32b. Be Similarly, for the fusion splice 34c, one end of the optical fiber ribbon 34a where the coating resin is peeled off and the bare fiber is exposed, and the fusion resin 34b of the optical fiber ribbon 34b where the coating resin is peeled off and the bare fiber is exposed One end is fusion-bonded to one another. The protective sleeve 34d covers the fusion splice 34c to protect the bare fiber. The protective sleeve 34d is provided from the surface of the coating resin of the optical fiber ribbon 34a to the surface of the coating resin of the optical fiber ribbon 34b so as to completely cover the bare fibers of the optical fiber ribbons 34a, 34b. Be

  The protective sleeves 32d and 34d have the same configuration as the protective sleeves 31d and 33d shown in FIG. Further, a multi-fiber optical connector 42 is attached to the other ends of the optical fiber ribbons 32a and 34a. The other ends of the optical fiber ribbons 32 b and 34 b are connected to the corresponding aggregated end 25.

  The positions of the fusion splices 32c and 34c in the longitudinal direction (X direction) of the optical fiber structure 30B are offset from each other. In other words, the fusion spliced part 32c is located between the fusion spliced part 34c and the aggregated end 25 in the X direction, and the fusion spliced part 34c has the fusion spliced part 32c and the multicore optical connector in the X direction. Located between 42 and

  Further, the protective sleeve 32d and the protective sleeve 34d do not overlap with each other (do not interfere with each other) in the stacking direction of the fusion spliced optical fiber ribbons 32, 34. Specifically, one end of the protective sleeve 32d on the side of the optical fiber ribbon 32a is located on the side of the aggregated end 25 with respect to one end of the protective sleeve 34d on the side of the optical fiber ribbon 34b. One end on the side of the fiber tape core 34b is located on the side of the multi-core optical connector 42 with respect to one end on the side of the optical fiber ribbon 32a of the protective sleeve 32d. Therefore, the entire protective sleeve 32d overlaps the optical fiber ribbon 34b, and the entire protective sleeve 34d overlaps the optical fiber ribbon 32a.

  Here, the fusion splicing method of the optical fiber according to the present embodiment will be described. FIG. 4 is a flowchart showing the fusion splicing method of the present embodiment. In the following description, although the optical fiber structure 30A is described as an example, the same applies to the optical fiber structure 30B.

  In this method, a first optical fiber ribbon including a plurality of optical fiber ribbons each including N / L optical fibers aligned in one direction is overlapped with N / L optical fibers aligned in one direction. The second optical fiber ribbons, each including L optical fibers, are connected to each other by fusion bonding. Here, the number L of 2 or more represents the number of optical fiber ribbons included in one optical fiber ribbon. Therefore, one end of one optical fiber ribbon included in the first optical fiber ribbon and one end of one optical fiber ribbon included in the second optical fiber ribbon are mutually set. The first step of fusing and the second step of covering the fusion spliced portion formed by the fusion with the protective sleeve are repeated for the number (L times) of the optical fiber ribbons.

  Specifically, first, the covering resin of a predetermined length is peeled off from one end of each of the optical fiber ribbons 31a and 31b to form a bare fiber. Then, one end of the optical fiber ribbon 31A and one end of the optical fiber ribbon 31b are fused to each other to form a fusion spliced part 31c (step S1, the first step described above). At this time, N / 2 optical fibers are simultaneously fused at the same position in the X direction. Next, the fusion spliced portion 31c is covered with a protective sleeve 31d (step S2, the second step described above). In this step, the protective sleeve 31d is previously passed through the optical fiber ribbon 31a or 31b, and after fusion, the protective sleeve 31d is moved to cover the fusion spliced portion 31c. Then, the heat-shrinkable tube 36 shown in FIG. 3 is shrunk by heating and the heat-meltable resin tube 38 is melted.

  Subsequently, the coating resin of a predetermined length is peeled off from one end of each of the optical fiber ribbons 33a and 33b to form a bare fiber. Then, the fusion spliced portion 33c is formed by fusing one end of the optical fiber ribbon fiber 33a and one end of the optical fiber ribbon fiber 33b to each other (step S3, the above-mentioned first step). At this time, N / 2 optical fibers are simultaneously fused at the same position in the X direction. Further, the position of the fusion spliced portion 33c in the X direction is shifted relative to the position of the fusion spliced portion 31c in the X direction. Next, the fusion spliced portion 33c is covered with a protective sleeve 33d (step S4, the above-mentioned second step). In this step, the protective sleeve 33d is previously passed through the optical fiber ribbon 33a or 33b, and after fusion, the protective sleeve 33d is moved to cover the fusion spliced portion 33c. At this time, the X-direction position of the protective sleeve 33d is determined so that the protective sleeve 33d does not overlap with the protective sleeve 31d. Then, the heat-shrinkable tube 36 shown in FIG. 3 is shrunk by heating and the heat-meltable resin tube 38 is melted. As described above, when the number of optical fiber ribbons is two, the first step and the second step are sequentially repeated only twice.

  The effects obtained by the fusion splicing method of the present embodiment described above, the optical fiber structures (fusion splice structures) 30A and 30B, and the optical wiring member 1A will be described together with the problems of the comparative example. (A) and (b) of FIG. 5 are a plan view and a cross-sectional view showing the configuration of the optical wiring member 100 as a comparative example. (A) of FIG. 5 is a plan view seen from the Z direction. FIG. 5B is a cross-sectional view along the XZ plane. The optical wiring member 100 includes optical fiber structures 130A and 130B instead of the optical fiber structures 30A and 30B of the present embodiment. In the optical fiber structures 130A and 130B, the fusion splices 31c and 33c are formed at the same X-direction position, and the protective sleeves 31d and 33d overlap each other. Similarly, the fusion splices 32c and 34c are formed at the same X-direction position, and the protective sleeves 32d and 34d overlap each other.

  FIG. 6 is an enlarged view of the optical fiber structure 130A. As shown in FIG. 6, when the protective sleeves 31d and 33d overlap each other, the distance between the fusion spliced portions 31c and 33c increases. As shown in FIG. 3, the protective sleeves 31d and 33d contain a reinforcing member 35 and a heat melting resin tube 38 for maintaining the mechanical strength of bare fibers, and the protective sleeves 31d and 33d are light beams. This is because it is much thicker than the fiber ribbons 31a, 33a, 31b, and 33b. The other ends of the optical fiber ribbons 31a and 33a are connected to the multifiber optical connector 41. However, when the distance between the optical fiber ribbons 31a and 33a in the multifiber optical connector 41 is set small, the optical fiber The tape cores 31a and 33a are inclined to be away from each other toward the fusion splices 31c and 33c. Therefore, if the distance between the fusion spliced parts 31c and 33c and the multicore optical connector 41 is short, there is a possibility that the optical fiber ribbons 31a and 33a may be excessively bent at the connection part A with the multicore optical connector 41. . When the optical fiber ribbons 31a and 33a are excessively bent, the bending loss of each of the optical fibers constituting the optical fiber ribbons 31a and 33a increases, and the optical fibers may be damaged. The other ends of the optical fiber ribbons 31b and 33b are connected to the aggregation end 23, but if the distance between the optical fiber ribbons 31b and 33b at the aggregation end 23 is set small, the optical fiber The tape cores 31b and 33b are inclined to be away from each other toward the fusion splices 31c and 33c. Therefore, if the distance between the fusion spliced portions 31c and 33c and the concentrated end portion 23 is short, there is a possibility that the optical fiber ribbons 31b and 33b may be excessively bent at the connection portion B with the concentrated end portion 23. When the optical fiber ribbons 31b and 33b are excessively bent, the bending loss of each of the optical fibers constituting the optical fiber ribbons 31b and 33b may be increased, and the optical fibers may be damaged. These problems similarly occur in the optical fiber structure 130B.

  On the other hand, in the fusion splicing method of this embodiment, the X direction positions of the fusion spliced parts 31c, 33c are mutually shifted so that the protective sleeves 31d, 33d do not overlap each other. Similarly, the positions of the fusion spliced portions 32c and 34c in the X direction are shifted from each other so that the protective sleeves 32d and 34d do not overlap each other. Further, in the optical fiber structure 30A of the present embodiment, the X direction positions of the fusion spliced portions 31c and 33c are shifted from each other, and the protective sleeves 31d and 33d do not overlap each other. Similarly, in the optical fiber structure 30B, the X-direction positions of the fusion splices 32c and 34c are shifted from each other, and the protective sleeves 32d and 34d do not overlap with each other. As a result, the distance between the fusion spliced parts 31c and 33c and the spacing between the fusion spliced parts 32c and 34c can be narrowed as compared with FIG. Excessive bending of 31a to 34a and 31b to 34b can be suppressed. Therefore, it is possible to suppress the bending loss of each of the optical fibers constituting the optical fiber ribbons 31a to 34a and 31b to 34b, and to reduce the damage to each of the optical fibers.

  FIGS. 7A and 7B are diagrams for explaining another effect of the fusion splicing method and the optical fiber structures 30A and 30B of the present embodiment. As shown in FIG. 7A, in the optical fiber structure 130A of the comparative example, the protective sleeves 31d and 33d overlap with each other, so the thickness T1 of the optical fiber structure 130A becomes thick. The same applies to the optical fiber structure 130B. Therefore, the miniaturization of the device provided with the optical fiber structures 130A and 130B is hindered. On the other hand, as shown in FIG. 7B, in the present embodiment, the protective sleeves 31d and 33d do not overlap with each other, so the thickness T2 of the optical fiber structure 30A can be reduced. Similarly, since the protective sleeves 32d and 34d do not overlap with each other, the thickness of the optical fiber structure 30B can be reduced. Therefore, the device provided with the optical fiber structures 30A and 30B can be miniaturized.

  Further, the optical wiring member 1A of the present embodiment includes the optical fiber structures 30A and 30B having the above-described effect, and the wiring portion 22 in which a plurality of optical fibers 20 are wired. For example, in a facility in which a large number of optical communication lines such as a base station for optical communication or a data center are laid, an optical line such as a shuffle optical line member is provided with a wiring portion in which a large number of optical waveguides (for example, optical fibers) are wired Parts are required. In such an optical wiring member, an optical fiber ribbon having a multicore optical connector is fused to an optical fiber ribbon extending from the wiring portion for connection to an external device. However, since the space of facilities such as base stations or data centers is limited, miniaturization of optical wiring members is required. The height required for the chassis of the shuffled optical wiring member is, for example, 10 mm or less. In addition, it is required that the optical loss be extremely low for the optical wiring members used in these facilities. The optical wiring member 1A according to the present embodiment includes the optical fiber structures 30A and 30B having the above-described effects, so that miniaturization is possible and optical loss can be reduced.

  The embodiment of the present invention has been described in detail with reference to the drawings, but the specific configuration is not limited to this embodiment. For example, in the above-described embodiment, an aspect in which two optical fiber ribbons are overlapped with each other in the fusion spliced structure (optical fiber structures 30A and 30B) is exemplified, but three or more optical fiber ribbons are illustrated. It may be superimposed on each other. Even in such a case, the same effects as those of the above embodiment can be obtained by mutually shifting the positions of the fusion splices.

  DESCRIPTION OF SYMBOLS 1A ... Optical wiring member, 20 ... Optical fiber, 22 ... Wiring part, 23, 25 ... Aggregation end part, 30A, 30B ... Optical fiber structure, 31-34 ... Optical fiber tape core wire with a fusion splicing part, 31a ~ 34a, 31b to 34b: optical fiber ribbon, 31c to 34c: fusion spliced part, 31d to 34d: protective sleeve, 35: reinforcing member, 36: heat shrinkable tube, 38: heat fusible resin tube, 41, 42 ... multi-core optical connector, A, B ... connection part, Sa, Sb ... edge part.

Claims (3)

A method of mutually interconnecting first and second optical fiber ribbons in which two or more optical fiber ribbons, each including a plurality of optical fibers arranged in one direction, are overlapped. ,
One end of the optical fiber tape core wire included in the first optical fiber tape core wire group and one end of the optical fiber tape core wire included in the second optical fiber tape core wire group And repeating the first step of mutually fusing, and the second step of covering the fusion-bonded portion formed by the fusion with a protective sleeve by the number of the optical fiber ribbons.
A fusion splice method of optical fibers, wherein positions of the fusion splices of the two or more optical fiber ribbons are mutually shifted so that the protective sleeves do not overlap with each other. First and second optical fiber ribbons in which two or more optical fiber ribbons each including a plurality of optical fibers arranged in one direction are overlapped with each other;
One end of each optical fiber ribbon included in the first optical fiber ribbon group and one end of each optical fiber ribbon included in the second optical fiber ribbon are mutually fused Two or more fusion splices, and
Two or more protective sleeves respectively covering the two or more fusion splices;
Equipped with
An optical fiber fusion splice structure in which the positions of the two or more fusion splices are mutually offset and the protective sleeves do not overlap each other. A plurality of fusion spliced structures according to claim 2;
A wiring portion in which a plurality of optical waveguides are wired;
Equipped with
A multi-fiber optical connector is attached to the other end of each of the first optical fiber ribbons,
The plurality of optical waveguides have an aggregated end portion aggregated for each of the corresponding second optical fiber ribbons.
The optical wiring member, wherein the aggregated end portion is positioned at an edge portion of the wiring portion and connected to the other end of the corresponding second optical fiber tape core group.

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