JP2005352510A - Optical fiber tape unit and optical fiber cable - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical fiber tape unit with which a coated optical fiber tape is hardly disconnected to respective optical fibers and can be easily branched, plural sheets of coated optical fiber tapes are connected and the live-line branching can be easily performed. <P>SOLUTION: The optical fiber tape unit is made by arranging the plural sheets of coated optical fiber tapes 1, which are made by arranging a plurality of the optical fibers 3 in parallel and integrating the optical fibers 3 over the whole length with resin 4, in parallel and connecting the coated optical fiber tapes 1 with a connecting resin 2. The coated optical fiber tapes 1 are satisfied by the following relation: T<SB>1</SB>≤d+40 (μm), wherein the maximum value of the thickness of the coated optical fiber tapes 1 is T<SB>1</SB>(μm) and an outer diameter of the optical fiber is d (μm). <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention provides an optical fiber tape unit in which a plurality of optical fiber ribbons in which the plurality of optical fibers are integrated with resin over the entire length are arranged in parallel, and the plurality of optical fiber ribbons are connected by a connecting resin. And an optical fiber cable using the optical fiber tape unit.

As an optical fiber tape core wire in which a plurality of optical fibers are arranged and integrated in a tape shape, for example, there is one described in Patent Document 1.
In Patent Document 1, as shown in FIG. 14, an optical fiber tape in which a colored layer is provided on the outermost periphery of the optical fiber and a collective coating layer is provided to cover the entire circumference of the optical fiber. In the embodiment of the core wire, reference numeral 101 denotes an optical fiber, which has an optical fiber 102 in the center, and a first covering layer 103 and a second layer made of, for example, an ultraviolet curable resin around it. The coating layer 104 is sequentially applied, and a colored layer 105 coated with a colored ink made of an ultraviolet curable resin is provided around the coating layer 104. A plurality of the coating layers, usually 4n ( n is 2, ...), and in this embodiment, 8 are arranged in parallel in one row. Reference numeral 106 is made of, for example, an ultraviolet curable resin in which the strands of the optical fiber strands 101 arranged in parallel are filled and integrated, and the outer periphery of the strand 101 is coated to a thickness h = 10 μm or less. It is a collective coating layer. (A) is the top view of the said optical fiber ribbon, Comprising: As clearly shown there, the lump coating layer 106 is stripped off intermittently in the longitudinal direction, and the optical fiber 101 The intermittent part 107 without the covering layer exposed is formed, and the covering part 108 where the covering layer 106 is left and the intermittent part are alternately arranged. (B) shows a cross-sectional view of the covering portion 108.

Moreover, as what connected the some optical fiber tape core wire, there exist some which were described in patent document 2, for example. In Patent Document 2, as shown in FIG. 15, a split type optical fiber ribbon 201, 202 is a glass fiber, 203 is a protective coating layer, 204 is a colored layer, 205 is a batch resin coating layer, and 206 is an optical fiber. A fiber tape core wire 207 is a connecting resin.
The full text of Japanese Utility Model Publication No. 4-75304 JP-A-10-197767

  When using a plurality of optical fibers, these optical fibers may be integrated with a resin and used as an optical fiber ribbon. The optical fiber ribbon may be branched from the optical fiber ribbon to the optical fiber depending on how the optical fiber is used. In this branching operation, if the number of optical fibers accommodated in the optical fiber ribbon is small, remove the integrated resin, dispose of each optical fiber, take out the required optical fiber, and branch off. Yes. However, in the case of an optical fiber ribbon that accommodates a large number of optical fibers, when the optical fiber is branched from the optical fiber ribbon, if the optical fibers are separated from each other, the optical fibers are entangled. Branching work takes time because everything is separated.

  Therefore, when a large number of optical fibers are integrated and used, a plurality of optical fibers are integrated into an optical fiber ribbon, and a plurality of optical fiber ribbons are arranged, and these optical fiber ribbons are connected. When connected and used as an optical fiber tape unit, branching work can be performed efficiently. As an example of the branching operation, when branching an optical fiber from an installed optical fiber tape unit, light that is not used as a transmission line from an optical fiber ribbon that is already part of the optical fiber used as a transmission line The fiber may be branched (hereinafter referred to as hot line branching).

  In the branching operation of the optical fiber tape unit including such a live wire, if there is a lot of resin that integrates the optical fiber or a lot of resin that connects the optical fiber tape core wires, when removing these resins However, it requires a lot of force and takes time for branching. Furthermore, when removing these resins, the optical fiber ribbon may be bent or pressed more than necessary. In such a case, the transmission loss of the optical fiber used as the transmission line is reduced. It can be increased or the optical signal can be interrupted. Conversely, if the resin that integrates the optical fiber is reduced or the resin that connects the optical fiber ribbons is reduced, the optical fiber cannot be integrated (taped), or the resin is applied with a slight external force. There is a possibility that cracks and breakage may occur and be scattered on each optical fiber. In particular, when the number of optical fibers is large, such a tendency is strong. Therefore, the resin that integrates the optical fibers and the resin that connects the optical fiber ribbons have an important influence on the hot branching. found.

  It is an object of the present invention to provide an optical fiber tape unit in which an optical fiber tape core is difficult to be scattered on each optical fiber and can be easily branched, and a plurality of optical fiber ribbons are connected to easily perform live line branching. It is to provide.

  An optical fiber tape unit according to the present invention includes a plurality of optical fiber tapes in which a plurality of optical fibers are arranged in parallel, and a plurality of optical fiber ribbons in which a plurality of optical fibers are integrated with resin over the entire length are arranged in parallel. An optical fiber tape unit in which cores are connected by a connecting resin, where the maximum value of the thickness of the optical fiber ribbon is T1 (μm) and the outer diameter of the optical fiber is d (μm), T1 An optical fiber ribbon that is ≦ d + 40 (μm) is used.

  Further, the optical fiber tape unit according to the present invention may use an optical fiber tape core wire in which the entire circumferences of a plurality of optical fibers are coated and integrated with resin, and T1 ≦ d + 25 (μm). A certain optical fiber ribbon may be used.

  The optical fiber tape unit according to the present invention may use an optical fiber ribbon in which adjacent optical fibers in the optical fiber ribbon are in contact with each other and integrated.

  Further, the optical fiber tape unit according to the present invention may use an optical fiber ribbon in which a concave portion is formed by a resin integrated according to a depression between adjacent optical fibers of the optical fiber ribbon.

  In the optical fiber tape unit according to the present invention, when the outer diameter of the optical fiber is d (μm) and the thickness of the concave portion of the optical fiber ribbon is g1 (μm), g1 ≦ d (μm) Or an optical fiber ribbon that satisfies g1 ≦ 0.8 × d (μm) may be used.

  In the optical fiber tape unit according to the present invention, the optical fiber tape has an adhesion force between the optical fiber and the resin integrating the optical fiber in the range of 0.245 (mN) to 2.45 (mN). A core wire may be used, and an optical fiber tape core wire in which the yield point stress of the resin integrated with the optical fiber is in the range of 20 (MPa) to 45 (MPa) may be used.

  The optical fiber tape unit according to the present invention may use an optical fiber whose loss increase at a wavelength of 1.55 μm is 0.1 (dB / turn) or less when the optical fiber is bent to a diameter of 15 mm. When the optical fiber tape unit is divided into optical fiber ribbons, the loss increase generated in the optical fiber may be 1.0 (dB) or less at a wavelength of 1.55 (μm).

In addition, when the optical fiber tape unit according to the present invention branches from the optical fiber ribbon to the optical fiber, an increase in loss generated in the optical fiber is 1.0 (dB) or less at a wavelength of 1.55 (μm). An optical fiber ribbon may be used, an optical fiber having a mode field diameter of 10 (μm) or less at a wavelength of 1.55 (μm), or a bundle of optical fiber tapes. An optical fiber ribbon having a polarization mode dispersion in a state of 0.2 (ps / km ^1/2 ) or less may be used.

  In the optical fiber tape unit according to the present invention, the connecting resin may be connected by covering the entire circumference of the plurality of optical fiber ribbons, and a part of the optical fiber ribbons may be connected. In an exposed state, a plurality of optical fiber ribbons may be connected by a connecting resin.

  Further, in the optical fiber tape unit according to the present invention, the connecting resin may be provided only in the recess formed by the optical fiber tape core wires, and the concave portion formed by the resin integrated with the optical fiber. May be provided with a connecting resin.

  In the optical fiber tape unit according to the present invention, T1 + 4 (μm) ≦ T2 (μm), where T2 is the maximum thickness of the optical fiber tape unit and T1 is the maximum thickness of the optical fiber ribbon. ) ≦ T1 + 25 (μm).

  Further, in the optical fiber tape unit according to the present invention, a valley portion may be formed by a connecting resin according to the depression between adjacent optical fiber tape core wires, and the thickness of the optical fiber tape core wire may be When the maximum value is T2 and the thickness at the valley is g2, g2 ≦ T1 may be satisfied.

  The optical fiber cable according to the present invention may be a collection of the optical fiber tape units of the present invention, and may further be provided with a tensile body.

  According to the optical fiber tape unit of the present invention, since the optical fiber ribbon is not easily separated and easily branched, a plurality of the optical fiber ribbons are connected. Can be easily performed. Further, since the resin connecting the optical fiber ribbons has a desired thickness and a desired shape, the optical fiber ribbons can be easily divided into hot wires. In addition, a plurality of optical fiber cores in which a plurality of optical fibers are integrated are connected, and when the optical fiber is branched, the optical fibers that are not branched can be collected as an optical fiber tape core.

  Hereinafter, an example of the best mode for carrying out the present invention will be described in detail with reference to the drawings and tables.

  1A is a cross-sectional view showing a first embodiment of an optical fiber tape unit according to the present invention, FIG. 1B is a perspective view thereof, and FIG. 1C is a cross-sectional view of an optical fiber. . In the optical fiber tape unit 100, a plurality of optical fiber ribbons 1 (two in this embodiment are used as an example) are arranged and connected around the optical fiber ribbons 1 and 1 with a resin 2. , Integrated. As the coupling resin 2, any resin such as a thermosetting resin or a thermoplastic resin can be applied. However, as an example, the coupling resin 2 is coupled using an ultraviolet curable resin. FIG. 1 shows an example in which the two optical fiber ribbons 1 and 1 are arranged in contact with each other, but the two optical fiber ribbons 1 and 1 are not in contact with each other. What was integrated is also contained in this invention.

  Each of the optical fiber ribbons 1 and 1 is integrally covered with a resin 4 in a state where a plurality of optical fibers 3 (four in this embodiment are used as an example) are in contact with each other, The resin 4 covers the four optical fibers over the entire length in the longitudinal direction of the optical fiber ribbon. As this resin, any resin such as a thermosetting resin or a thermoplastic resin can be used, but as an example, an ultraviolet curable resin is used in the present embodiment. The optical fiber ribbon 1 is integrated by bringing the optical fibers 3 into contact with each other, but those in which the optical fibers 3 are not in contact with each other are also included in the present invention. Here, being in contact means that at least two optical fibers 3 included in the optical fiber ribbon 1 or at least two optical fiber ribbons 1 included in the optical fiber tape unit 100 are in contact. This means that at least two optical fibers 3 or at least two optical fiber ribbons 1 are not in contact.

  Comparing the case where the optical fiber tape cores 1 or the optical fibers 3 are in contact with the case where they are not in contact, the one in contact is divided from the optical fiber tape unit 100 into the optical fiber tape core 1. The optical fiber tape core wire 1 tends to branch to the optical fiber 3. When the optical fiber ribbons 1 or 3 are not in contact with each other, the distance between the optical fibers 1 or 3 is preferably about 10 μm or less in consideration of branching. This makes it possible to reduce the amount of resin that enters between the optical fiber ribbons 1 and to reduce the amount of resin that enters between the optical fibers 3, thus making it easy to split live lines and branch hot lines. Because it can.

  FIG. 1C shows a cross-sectional view of an optical fiber used in the optical fiber tape unit according to the present invention. The optical fiber 3 includes a glass fiber 5 including a core 5 a and a clad 5 b, the glass fiber 5 is covered with a protective coating 6 on the outer periphery thereof, and the outer periphery of the protective coating 6 is further covered with a colored layer 7. The glass fiber applicable to the present invention is not limited to the glass fiber 5 described above, and a glass fiber having any refractive index distribution such as a glass fiber including a core and a plurality of cladding layers can be used. Further, the protective coating 6 may be composed of a plurality of protective coatings, and even an optical fiber that does not include the colored layer 7 is applicable to the present invention.

  In the optical fiber tape unit 100 of this embodiment, the optical fiber ribbons 1 and 1 are covered with a resin 2, and the resin 2 has flat portions 2a and 2a. Further, the optical fibers of the optical fiber ribbons 1 and 1 are integrated with a resin 4, and the resin also has flat portions 4a and 4a. In such an optical fiber unit 100, when some optical fibers are used as transmission lines and other parts are not used as transmission lines, the optical fiber unit 100 including them is not used as a transmission line. Taking out the used optical fiber is called live branching.

  This live branching operation will be described with reference to FIGS. FIG. 2 is a cross-sectional view illustrating a method of dividing an optical fiber tape unit 100 including two optical fiber ribbons 1 and 1 into two optical fiber ribbons 1 and 1. The dividing tool 10 includes an upper mold 11 and a lower mold 12. The upper mold 11 is fixed to the upper frame 13 at the upper part thereof, and the lower mold 12 is fixed to the lower frame 14 at the lower part thereof. Further, the upper frame 13 is fixed to the upper guide 15 at one end thereof, and the lower frame is fixed to the lower guide 16 at one end thereof. When the optical fiber tape unit 100 is divided, both guides 15 and 16 are By following the side surfaces of the upper and lower molds 11 and 12, accurate vertical movement of the dividing tool 10 is realized.

  First, the dividing tool 10 is arranged at the dividing position of the optical fiber tape unit 100, and the optical fiber tape unit 100 is arranged between the upper mold 11 and the lower mold 12, as shown in FIG. The upper frame 13 is lowered downward so that the upper guide 15 is along the side surface of the lower mold 12, and is moved in the direction of arrow A until the lower surface 15a of the upper guide 15 contacts the upper surface 14a of the lower frame. . At this time, the resin 2 between the two optical fiber ribbons 1 and 1 is torn off by the upper die 11 and the lower die 12, and as shown in FIG. It is divided into 1 and 1. In the dividing method using the dividing tool 10, the upper frame 13 is divided by moving it downward. However, the lower frame 14 may be moved upward, and the upper and lower frames 13, 14 may be connected to each other. It may be moved.

  Next, as shown in FIG. 3, the split rod 20 is sandwiched between the split portions 2A and moved in the longitudinal direction (arrow B direction) of the optical fiber tape unit 100 to enlarge the split portion 2A. In this divided portion 2A, the connection between the two optical fiber ribbons 1 and 1 is broken, and the necessary optical fiber 3 is taken out from one of the optical fiber ribbons 1 among them. Become. At this time, since the connecting resin 2 is attached around the optical fiber ribbon 1, the connecting resin 2 is removed.

  FIG. 4 shows an example of an operation for removing the connecting resin 2 using the removal brush 25. The removal brush (removal tool) 25 has an upper base 26 and a lower base 27 provided with wire rods 28 and 29, respectively. The optical fiber tape core wire 1 is sandwiched between the wire rods 28 and 29, and the removal brush 25 The connecting resin 2 is removed from the optical fiber tape core 1 by reciprocating 25 or moving one side of the optical fiber tape core 25 in the longitudinal direction of the optical fiber tape core 1. In addition, as long as the kind, shape, dimension, etc. of a wire can be hot-wire branched, any kind is applicable.

  When the connecting resin 2 is removed from the optical fiber ribbon 1, the integrated resin 4 with which the optical fiber 3 is integrated is removed using a branch brush 30 as shown in FIG. The branch brush 30 (branch tool) is provided with wire rods 33 and 34 on an upper base 31 and a lower base 32, respectively. The optical fiber tape core wire 1 is disposed between the wire rods 33 and 34, and is integrated resin. 4 is sandwiched between the wire rods 33 and 34, and the branch brush 30 is reciprocated or moved to one side to remove the integrated resin 4. In addition, as long as the kind, shape, dimension, etc. of a wire can be hot-wire branched, any kind is applicable.

  In the above-described hot-line branching operation, the removal brush 25 is used to remove the connecting resin 2 and the branch brush 30 is used to remove the integrated resin 4. However, when the required optical fiber 3 is taken out. If live line branching is possible, the connecting resin 2 and the integrated resin 4 can be removed by one branch tool. Further, when one of the two optical fiber ribbons 1 and 1 is hot-branched and the optical fiber 3 is taken out, the other optical fiber ribbon 1 is not required to be branched. The optical fibers 3 can be gathered together with the optical fiber ribbon 1 without separating the optical fibers.

  In the live branching described above, the flat portion 2a of the resin 2 that covers and connects the optical fiber ribbon 1 of the optical fiber unit 100 and the resin 4 that integrates the optical fiber 3 of the optical fiber ribbon 1 are integrated. It has been found that the flat portion 4a has a great influence on the transmission loss of the optical fiber used as the transmission path. In other words, good branching workability, suppression of increase in transmission loss at the time of hot branching, and optical fiber tape cores should be made so that a plurality of optical fibers are not integrated (maintained integration). In view of the above, it has been found that there is a certain range in the thickness of the flat portions 2a and 4a.

  Table 1 shows branching and transmission loss when four optical fibers 3 having an outer diameter d = 250 μm are used and the thickness of the flat portion 4a of the resin 4 in which these optical fibers 3 are integrated are changed. The result of examining the increase (live line loss increase) is shown. Here, the thickness of the flat portion 4a of the resin 4 indicates a maximum value T1 of the thickness of the optical fiber ribbon 1 as shown in FIG.

  In Table 1, branching is evaluated by the time required for the branching work (branch time) from the optical fiber tape core to branching the optical fiber. When the branching time is 5 minutes or more, the branching is indicated by x. When the branching time is within 5 minutes, Δ is shown when it is within 3 minutes. The increase in hot line loss in Table 1 is indicated by x when the increase in transmission loss of the optical fiber at the time of branching is 1.0 dB or more at a wavelength of 1.55 μm, and Δ, 0.5 dB when 1.0 dB or less. It is indicated by ○ in the following cases. The resin thickness t1 represents the distance between the common tangent S1 of the optical fiber 3 and the flat portion 4a.

  Here, FIG. 6 shows a method of measuring the increase in loss at the time of branching. As shown in FIGS. 6A and 6B, an optical fiber tape unit 100 is prepared, and the glass fibers of the fiber 3a and the optical fiber 3e are respectively connected to the light source 40 from one end. At the other end of the optical fiber tape unit 100, the glass fibers of the two optical fibers 3a and 3d are fused and the glass fibers of the two optical fibers 3e and 3h are fused. On one end side of the optical fiber tape unit 100, the glass fibers of the two optical fibers 3d and 3h are connected to the light receiver 41, respectively. The light receiver 41 is connected to a storage oscilloscope 42, thereby measuring an increase value of transmission loss when splitting from the optical fiber tape unit or an increase value of transmission loss when branching from the optical fiber ribbon.

  When light having a wavelength of 1.55 μm is derived from the light emitter 41, the light is sent to the optical fibers 3 a and 3 e, received by the light receiver 41 through the optical fibers 3 d and 3 h, and then received by the storage oscilloscope 42. It is converted into the amount (value) of transmission loss. As shown in FIG. 6 (C), the optical fiber tape unit 100 is divided into two optical fiber tape cores 1 and 1 and this divided area is enlarged by about 50 cm in the longitudinal direction. Measure the increase in loss. Thereafter, one of the optical fiber ribbons 1 is branched into four optical fibers 3e, 3f, 3g, and 3h, and an increase in transmission loss at the time of branching is measured.

  As shown in Table 1, when the resin thickness t1 was 25 μm, the evaluation of branching property and increase in hot line loss were both x, and the hot line could not be branched. In this case, since the resin 4 is thick, the branching operation takes time and the increase in the loss of the optical fiber is large. If the resin thickness t1 was 20 μm or less, that is, T1 ≦ d + 40 μm, the live lines could be branched. When the resin thickness t1 was 15 to 20 μm, there was a slight increase in loss, but the live line could be branched without instantaneously interrupting the optical signal of the optical fiber. Furthermore, when the resin thickness t1 was 5 to 12.5 μm, that is, when T1 ≦ d + 25 μm, the live lines could be satisfactorily branched in a short time with almost no increase in loss. Further, when the optical fiber tape core is T1 ≦ d + 40 μm or T1 ≦ d + 25 μm, the optical fiber is integrated without being scattered even if the resin with which the optical fiber 3 is integrated is thin. It was also confirmed that the sex can be maintained.

  In the optical fiber tape unit according to the present embodiment, the entire circumference of a plurality of optical fiber ribbons is covered with a connecting resin. Therefore, when the optical fiber tape unit is divided into optical fiber ribbons, even if an external force or the like acts to crack the resin that integrates the optical fiber, it is covered with the connecting resin. Integration maintenance as a fiber tape core is possible.

  In the optical fiber tape unit according to the present invention, whether or not hot branching is possible also affects the characteristics of the optical fiber used. For example, when the optical fiber 3 is bent to a diameter of 15 mm, if the increase in loss at a wavelength of 1.55 μm is 0.1 dB / turn or less, live branching is possible. By using such an optical fiber that is resistant to small-diameter bending, an increase in loss can be suppressed even if it is bent during a branching operation. Under the above conditions, if the increase in loss exceeds 0.1 dB / turn, the hot branch may not be possible depending on the way of working at the branch.

Moreover, if the mode field diameter (MFD) at a wavelength of 1.55 μm of the optical fiber used in the present invention is 10 μm or less, it is possible to suppress an increase in loss at the time of hot branching, and if the MFD exceeds 10 μm, Depending on the way of branching, hot branching may not be possible. In order to improve the transmission capacity, wavelength division multiplexing (WDM) technology for overlapping signals of a large number of subscribers on one optical fiber is effective, and an optical fiber cable that has a small PMD and can be transmitted at high speed and long distance. desired. When the link PMD is 0.2 (ps / km ^1/2 ) or less as in the optical fiber unit according to the present invention, the transmission distance is 625 km when the transmission speed is 40 Gbps, and the transmission speed is 80 Gbps. 156 km, more preferable.

  Further, the optical fiber ribbon used in the present invention may affect the increase in transmission loss at the time of branching and the branching work efficiency depending on the material of the resin 4 integrated with the optical fiber. The material of the resin 4 is preferably such that the yield point stress is in the range of 20 MPa to 45 MPa, and branching can be easily performed, or transmission loss at the time of hot branching can be suppressed. The yield point stress of the resin is measured according to JIS-K7113 with a No. 2 test piece at a pulling speed of 50 mm / min. When the yield point stress is less than 20 MPa, when the optical fiber tape unit is formed, the resin may be cracked by an external force and scattered to the optical fiber. On the other hand, when the yield stress of the resin exceeds 45 MPa, it is difficult to remove the resin at the time of branching, and branching workability may not be good.

  In the optical fiber ribbon used in the present invention, it is desirable that the adhesion between the optical fiber and the resin in which the optical fiber is integrated is in the range of 0.245 mN to 2.45 mN. If the adhesion is within this range, the optical fiber can be easily branched. When the adhesion force is less than 0.245 mN, the adhesion force is small, the optical fiber is easily separated from the optical fiber ribbon, and it may be difficult to maintain the integrity as the optical fiber ribbon. On the other hand, if the adhesion force exceeds 2.45 mN, it may be difficult to perform good branching work, or the colored layer or protective coating of the optical fiber may be peeled off during branching.

  A method for measuring the above-described adhesion force will be described with reference to FIG. One side and approximately half of the resin integrated with the optical fiber 3 of the optical fiber ribbon 1 are removed to expose the optical fiber 3. An arbitrary optical fiber is taken out from the integrated resin 4 so as to be lifted, and the force at that time is measured.

  In the optical fiber unit according to the present invention, the thickness of the resin covering and connecting the plurality of optical fiber ribbons may affect the hot branching. If this resin coating is thick, for example, when branching to two optical fiber ribbons, a large force is required, and this large force may act on the optical fiber, making it impossible to branch the live line. As a result of examining the thickness of this resin, it was confirmed that if the resin thickness is in the range of 2 μm to 12.5 μm, the optical fiber can be satisfactorily branched from the optical fiber tape unit. That is, as shown in FIG. 1, when the maximum value of the thickness of the optical fiber tape unit is T2, and the maximum value of the thickness of the optical fiber ribbon is T1, T1 + 4 (μm) ≦ T2 (μm) ≦ T1 + 25 If it is within the range of (μm), the increase in transmission loss when splitting into the optical fiber ribbon 1 becomes 1.0 dB or less at a wavelength of 1.55 μm, so that live line branching can be performed satisfactorily.

  When the resin thickness is less than 2 μm, it is difficult for a plurality of optical fiber tape cores to maintain their integrity as an optical fiber tape unit, and even when a small external force is applied, the optical fiber tape core wires are easily separated. There are many cases. On the other hand, if the resin thickness exceeds 10 μm, a large force is required when dividing into optical fiber ribbons, and as described above, live line branching becomes difficult.

  FIG. 8 shows a second embodiment of the optical fiber tape unit according to the present invention, in which (A) is a sectional view, (B) is a perspective view, and (C) is a sectional view of the optical fiber. As an example, the optical fiber tape unit 100A has two optical fiber ribbons 1A and 1A, and the outer periphery of the two optical fiber ribbons 1A and 1A is connected by a connecting resin 2. As an example, the optical fiber ribbon 1 </ b> A is obtained by integrating the outer periphery of four optical fibers 3 with a resin 4. The contact / non-contact between the optical fiber ribbons 1A, 1A or the contact / non-contact between the optical fibers 3, 3 is the same as in the first embodiment, and the description thereof is omitted here. The configuration and other applications of the optical fiber used in this embodiment are the same as those in the first embodiment, and a description thereof is omitted.

  In the optical fiber ribbon 1A according to the present embodiment, the outer peripheral shape of the resin 4 with which the optical fiber 3 is integrated is different from that of the first example. That is, at the depression formed by the adjacent optical fibers 3 and 3, the resin integrated according to the depression forms the depression 4b. Therefore, the hot line branching work can be performed better and easily. That is, the resin 4 in which the optical fiber 3 is integrated, and the concave resin 4b formed at the recess between the optical fibers 3 and 3 is thinner than the optical fiber tape core wire 1 of the first embodiment. The integrated resin can be easily removed.

  As shown in FIG. 1, the result shown in Table 2 below is that the outer diameter d of the optical fiber 3 is 250 μm and the maximum thickness T1 of the optical fiber ribbon 1A is 290 μm, that is, the optical fiber 3 is integrated. The thickness of the resin is 20 μm, and the depth Y of the concave portion 4b described above is changed in various ways, and the branching property and the increase in the hot wire loss are examined. The recess depth Y refers to the distance between the common tangent S2 on the outer periphery of the integrated resin 4 of the optical fiber ribbon 1A and the bottom of the recess 4b. The branching method was the same as that in the first embodiment. In addition, Δ and ○ in each column of Table 2 indicate the same evaluation results as in Table 1. In the evaluation of branching property, ◎ indicates that the branching time is within 2 minutes. Further, as shown in FIG. 1, the thickness of the concave portion of the optical fiber ribbon 1A is g1.

  From the results shown in Table 2, when the depth of the recess is in the range of 1 to 10 μm, the evaluation of the branching property and the increase in the live line loss is Δ, and although the transmission loss increased, the branching operation was performed over time. For example, the live line could be branched. Although the transmission loss increased when the depth Y of the recess was in the range of 20 to 40 μm, the branching operation could be performed satisfactorily. That is, at the recess depth Y of 20 to 30 μm, the thickness g1 of the optical fiber ribbon 1A in this recess is 250 to 210 μm, which is smaller than the outer diameter d of the optical fiber 3 = 250 μm. Therefore, if g1 ≦ d, branching can be performed satisfactorily. Furthermore, when the concave portion depth Y is in the range of 50 to 100 μm, an increase in transmission loss can be suppressed and the evaluation of branching becomes ◎, and branching can be performed very well. From the above results, it was confirmed that when T1 ≦ d + 40 μm and the recess depth Y was increased, extremely good branching workability was exhibited.

  Next, when the maximum thickness T1 of the optical fiber ribbon 1A is 275 μm, that is, the thickness 4 of the resin integrated with the optical fiber 3 is 12.5 μm, the depth Y of the concave portion is variously changed to be branched. Table 3 shows the results of examining the increase in the hot wire loss. The other conditions are the same as those used in Table 2. In Table 3, the evaluation of the increase in the hot wire loss indicates that the increase in the loss of the optical fiber at the time of branching was 0.2 dB or less at a wavelength of 1.55 μm.

  In the range where the recess depth Y is 1 to 10 μm, the evaluation of branching property and increase in hot wire loss are both good, and the hot wire can be branched well. When g1 <d, the evaluation of the branching property was further improved, and it was marked as ◎, and the branching was very good. Furthermore, when the relationship of g1 <0.8d was satisfied, the evaluation of the increase in the live line loss was evaluated as “◎”, the increase in the transmission loss was considerably suppressed, and the live line branching was very good. Compared to the optical fiber ribbon used in Table 2, the optical fiber tape used in Table 3 has a thinner resin integrated with the optical fiber, and therefore, T1 ≦ d + 20 μm, and g1 It was confirmed that extremely good branching properties were obtained when <d or g1 <0.8d. It was also confirmed that even if the integrated resin 4 of the optical fiber ribbon 1A is thin like this, the integration can be sufficiently maintained against some bending.

  In the optical fiber ribbon 1A used in Table 2 or Table 3, the characteristics of the optical fiber 3, the characteristics of the resin 4 in which the optical fiber 3 is integrated, the adhesion between the optical fiber 3 and the resin 4, etc. This is the same as in the first embodiment, and the description thereof is omitted here.

  Next, the splitting property to the optical fiber tape core 1A when the thickness t2 of the resin connecting the optical fiber tape cores 1A of the optical fiber tape unit 100A according to the present embodiment is changed, the hot wire loss The increase and the damage resistance were examined, and the results are shown in Table 4. The resin thickness t2 refers to the distance between the flat portion 2a of the resin 2 of the optical fiber tape unit 100A and the common tangent S2 on the outer periphery of the integrated resin 4 of the optical fiber ribbon 1A. The dividing method is performed using the method shown in FIG. 2. In the evaluation, Δ can be divided into the optical fiber ribbons 1A and 1A, but the resin 4 in which the optical fibers are integrated in the optical fiber ribbon. Part of this indicates that the upper and lower molds 11 and 12 (see FIG. 2) rubbed or peeled off. The mark “◯” in the evaluation of the splitting property indicates that although the rubbing or peeling occurred slightly, the splitting was possible. The increase in the hot wire loss is a measured value measured by the method shown in FIG. 6C, and the evaluation Δ is that the loss increase value is 1.0 dB or less, and the ◯ mark is 0.5 dB or less. It shows that there was. As shown in FIG. 8, the used optical fiber ribbon 1A has an outer diameter d = 250 .mu.m of the optical fiber 3, the maximum thickness of the optical fiber ribbon 1A is 290 .mu.m, and the adjacent optical fibers 3, 3. The resin 4 that integrates the optical fibers according to the depressions formed by the step 4 forms the recess 4b.

  The test method of the damage resistance shown in Table 4 will be described with reference to FIG. The optical fiber tape unit 100 </ b> A according to the present embodiment is wound around the bobbin 45, and the optical fiber tape unit 100 </ b> A is unwound from the bobbin 45 and wound on the downstream bobbin 46. On the way, accumulator rollers 47 and 48 are provided. A 400 g weight is suspended from the accumulator roller 48. The optical fiber tape unit 100A passes through the accumulator rollers 47 and 48. Further downstream, two fixing rods 49 and 50 are provided, and the optical fiber tape unit 100A is bent by approximately 90 degrees while being subjected to friction by the first fixing rod 49.

  Further, the optical fiber tape unit 100A is bent by approximately 90 degrees while receiving friction in the second fixed rod 50 downstream, and accordingly, both surfaces of the optical fiber tape unit 100A are squeezed. The squeezed optical fiber tape unit 100A is wound around the bobbin 46, and the wound optical fiber tape unit 100A is inspected for trauma. In this evaluation of the trauma resistance, the case where the optical fiber tape core wire was broken due to breakage of the connecting resin 2 of the optical fiber tape unit 100A was marked with a cross. Further, even when scratches or the like occur in the connecting resin 2, the case where the integrity of the optical fiber tape unit 100A is maintained is indicated by Δ, and the case where no faint scratches are generated on the connecting resin is indicated by ○.

  From the results shown in Table 4, when the thickness t2 of the resin 2 connecting the optical fiber ribbons 1A is in the range of 20 to 25 μm, the evaluation of splitting property and increase in hot wire loss is both Δ, and the split optical fiber Even though the tape core wire 1A was rubbed or slipped, it could be divided. This is because the connecting resin connecting the optical fiber ribbons 1A is thick, and when divided, the connecting resin is pressed by the upper and lower molds 11 and 12, and the optical fiber tape unit 100A is divided in a twisted state. it is conceivable that. Further, the evaluation of the damage resistance was “good”, and the integrity was satisfactorily maintained without being scattered on the optical fiber ribbon.

  When the thickness of the connecting resin 2 was reduced to 12.5 μm, the evaluation of splitting was “good”, and the live lines could be split although there was a slight increase in transmission loss. Furthermore, when the thickness of the connecting resin 2 was 5 μm or 2 μm, the evaluation of the increase in the live line loss was also good, and the live line was successfully divided. It was confirmed that the damage resistance was evaluated as “good”, and the integrity could be maintained well without being scattered on the optical fiber ribbon. From the above, when the connecting resin is thinned, the splitting property is improved. When the maximum thickness of the optical fiber ribbon 1A is T1 and the maximum thickness of the optical fiber tape unit is T2, T1 + 4 μm ≦ T2 μm ≦ T1 + 25 μm It was confirmed that if it was within the range, a good live line dividing operation could be performed.

  Table 5 shows the results of examining the splitting property, the increase in hot wire loss, and the damage resistance using the optical fiber ribbon 1A having a maximum thickness of 275 μm. The configuration of the optical fiber unit is the same except that the maximum thickness of the optical fiber ribbon 1A is different, and the same method and the same evaluation as those shown in Table 4 were performed.

  From the results shown in Table 5, the same evaluation results as in the case of the optical fiber tape core wire 1A having a thickness of 290 μm used in Table 4 were obtained for the splitting property, the increase in the hot wire loss, and the damage resistance. That is, when the thickness of the connecting resin is in the range of 20 to 25 μm, both the splitting property and the evaluation of increase in the hot wire loss are Δ, while the evaluation of the scratch resistance is ○, and when the connecting resin thickness is 10 μm, the splitting is performed. When the property was improved to ◯ and the thickness of the connecting resin was 2 μm or 5 μm, all evaluations of splitting property, increase in hot wire loss, and damage resistance were ◯. Therefore, as in the case of Table 4, it was confirmed that a satisfactory hot-line dividing operation could be performed within the range of T1 + 4 μm ≦ T2 μm ≦ T1 + 25 μm.

  In the optical fiber tape unit 100A used in Table 4 or Table 5, the characteristics of the optical fiber 3, the characteristics of the resin 4 with which the optical fiber 3 is integrated, the adhesion between the optical fiber 3 and the resin 4, etc. This is the same as in the first and second embodiments, and the description thereof is omitted here.

  FIG. 10 shows a third embodiment of the optical fiber tape unit according to the present invention. In this optical fiber tape unit 100B, the outer circumferences of two optical fiber ribbons 1B and 1B are connected by a resin 2. In the optical fiber ribbon 1B, a resin 4 integrated with an optical fiber forms a recess 4b in a recess formed by adjacent optical fibers 3, 3, and the second embodiment described above. This is the same as the optical fiber ribbon 1A used in the above. In the connecting resin 2 connecting the optical fiber ribbons 1B, the connecting resin 2 forms a valley 2c in accordance with the depression formed by the two optical fiber ribbons 1B and 1B. . The valley 2c is effective when the optical fiber tape unit 100B is divided into the optical fiber ribbons 1B and 1B. That is, since the connecting resin 2 forms the troughs 2c at the divided portions and thins the connecting resin, for example, when the dividing resin 10 is divided into the optical fiber ribbons 1B and 1B using the dividing tool 10 shown in FIG. It can be easily divided with a small force.

  In this third embodiment, the dividing property and activity when the optical fiber tape unit 100B is divided into the optical fiber ribbons 1B by changing the depth of the valley 2c of the connecting resin 2 of the optical fiber tape unit 100B are various. Table 6 shows the results of examining the increase in line loss. Here, the thickness of the optical fiber tape unit at the trough 2c is g2, and the trough depth Y1 is the distance from the flat portion 2a of the connecting resin 2 to the deepest bottom of the trough 2c. The optical fiber ribbon 1B used is the same as that shown in Table 4, and the maximum thickness T1 of the optical fiber ribbon 1B is 290 μm. In addition, the evaluation of the splitting evaluation and the evaluations Δ and ○ of the increase in the live line loss are the same as those in Tables 4 and 5. “A” in the evaluation of the splitting property indicates that the optical fiber tape core wire 1B was hardly scraped or peeled off at the time of splitting and could be split very well. The evaluation ◎ of the increase in the hot wire loss indicates that the loss increase value was 0.2 dB or less. The maximum thickness of the optical fiber tape unit 100B is 315 μm.

  As shown in Table 6, when the valley depth Y1 is 1 μm to 10 μm, the division property was good, but an increase in transmission loss was observed. This is because the valley 2c is shallow, This is probably because the effect of the part 2c is not achieved. When the trough depth Y1 was as deep as 20 μm, the effect of the trough 2c began to appear, and the evaluation of the splitting property and the increase in the hot line loss was both good. When the valley portion 2c depth Y1 is in the range of 20 to 50 μm, the evaluation of the splitting ability becomes “◎”, and the live line splitting can be performed extremely well. In addition, the increase in the live line loss was evaluated as ○ and ◎, and the increase in transmission loss could be suppressed. Accordingly, when the valley portion 2c is formed in the connecting resin 2, the splitting property increases the hot wire loss, and in particular, the maximum value of the thickness of the optical fiber ribbon 1B is T1, and the optical fiber tape unit at the valley portion 2c. When the thickness of 100B was g2, it was confirmed that live line division could be performed very well when g2 ≦ T1.

  Next, when the optical fiber tape core wire 1B having a maximum thickness as thin as 275 μm was used, the division property and the increase in the hot wire loss were examined, and the results are shown in Table 7. Except the thickness of the optical fiber ribbon 1B is 275 μm, it is the same as that used in Table 6. The maximum thickness of the optical fiber tape unit 100B is 300 μm.

  It can be confirmed that even when the valley depth Y1 is 1 μm, the splitting property is good, and if the optical fiber tape core wire 1B is thin, the splitting property can be improved even if the slight valley portion 2c is formed. It was. In the range where the valley depth Y1 is in the range of 20 to 50 μm, it was confirmed that the live line was divided very well as in Table 6. Regarding the increase in hot wire loss, when the optical fiber ribbon 1B was thin, the evaluation was good or bad. Further, as in Table 6, it was confirmed that the live line could be divided very well when g2 ≦ T1.

  In the optical fiber tape unit used in Table 6 or Table 7, the characteristics of the optical fiber ribbon, the characteristics of the optical fiber 3, the characteristics of the resin 4 in which the optical fiber 3 is integrated, and the adhesion between the optical fiber 3 and the resin 4 About force etc., it is the same as that of 1st, 2nd embodiment, The description was abbreviate | omitted here.

  Next, a fourth embodiment of the optical fiber tape unit according to the present invention will be described with reference to FIG. In this optical fiber tape unit 100C, as an example, two optical fiber ribbons 1C and 1C are arranged, and a connecting resin 2d is provided only at a recess formed by the optical fiber ribbons 1C and 1C. It is connected. Therefore, the optical fiber ribbon 1C is exposed except for the connecting resin 2d. The optical fiber ribbon 1C has a plurality of optical fibers integrated by an integrated resin 4 and a recess 4b, which is the same as that described in the second and third embodiments. Description is omitted.

  When such an optical fiber tape unit 100C is used, for example, when dividing into two optical fiber tape cores 1C and 1C, live line division can be easily performed without using a dividing tool. Alternatively, the connecting resin 2d can be peeled simply by bending the two optical fiber ribbons 1C and 1C to each other.

  Next, 5th Embodiment of the optical fiber tape unit concerning this invention is described using FIG. As an example, this optical fiber tape unit 100D is obtained by connecting two optical fibers 1D and 1D similar to those shown in the second to fourth embodiments by a connecting resin 2. The resin 2 is attached so that the concave portion 4b of the resin 4 integrating the optical fiber of the optical fiber ribbon 1D is filled with the resin 2e, and is formed by the optical fiber ribbons 1D and 1D. It is connected by resin 2f at the depression. The optical fiber ribbon 100D is exposed from the optical fiber ribbon 1D except for the resin 2e and the resin 2f, and is entirely flat due to the exposed optical fiber ribbon, the resin 2e, and the resin 2f. It has become. Therefore, when such an optical fiber tape unit 100D is laminated and used, it becomes easy to laminate. Further, since the amount of the resin 2 (2e, 2f) used is small, the splitting property and the branching property are good. Furthermore, since the recess 4b is filled with the resin 2e, the resin 2e can prevent the optical fiber tape core wire from being bent even if it is about to be bent unexpectedly.

  As described above, the optical fiber tape unit according to the present invention has been described with two optical fiber tape cores arranged side by side. However, the present invention is not limited to this example of the present invention. An example is shown in FIG. FIG. 13A shows an optical fiber tape unit 100E in which three optical fiber ribbons 1E in which four optical fibers 3 are integrated are connected by a connecting resin 2. FIG. 13B shows an optical fiber tape unit 100 </ b> F in which four optical fiber ribbons 1 </ b> F integrated with two optical fibers 3 are connected by a connecting resin 2. Also, a plurality of optical fiber tape units according to the present invention can be used to collect the optical fiber cables to form an optical fiber cable. Further, a plurality of SZ-direction grooves can be formed in the circumferential direction in a slot in which a tensile strength member is arranged at the center, and an optical fiber cable in which a plurality of optical fiber tape units according to the present invention are laminated in these grooves can be obtained.

1A and 1B show a first embodiment of an optical fiber tape unit according to the present invention. FIG. 1A is a sectional view, FIG. 1B is a perspective view, and FIG. 1C is a sectional view of an optical fiber. 2A and 2B are cross-sectional views of the dividing tool of the optical fiber tape unit according to the present invention, in which FIG. 2A shows before division and FIG. 2B shows after division. FIG. 3 is a perspective view showing a place where the divided portion of the optical fiber tape unit according to the present invention is opened. FIG. 4 is an explanatory view showing a state where the connecting resin is removed from the optical fiber ribbon of the optical fiber tape unit according to the present invention. FIG. 5 is an explanatory view showing the removal of the integrated resin of the optical fiber ribbon of the optical fiber tape unit according to the present invention. FIG. 6 is an explanatory diagram showing a measurement method for measuring transmission loss at the time of splitting and branching of the optical fiber tape unit according to the present invention. FIG. 7 is a perspective view showing a measuring method for measuring the adhesion force between the optical fiber tape core integrated resin and the optical fiber of the optical fiber tape unit according to the present invention. FIG. 8 shows a second embodiment of the optical fiber tape unit according to the present invention, in which (A) is a sectional view, (B) is a perspective view, and (C) is a sectional view of the optical fiber. FIG. 9 is an explanatory view showing a test method for the damage resistance of the optical fiber tape unit according to the present invention. FIG. 10 shows a third embodiment of an optical fiber tape unit according to the present invention, in which (A) is a cross-sectional view, (B) is a perspective view, and (C) is a cross-sectional view of the optical fiber. FIG. 11 shows a fourth embodiment of an optical fiber tape unit according to the present invention, in which (A) is a cross-sectional view, (B) is a perspective view, and (C) is a cross-sectional view of the optical fiber. FIG. 12 shows a fifth embodiment of an optical fiber tape unit according to the present invention, in which (A) is a sectional view, (B) is a perspective view, and (C) is a sectional view of the optical fiber. FIG. 13 is a cross-sectional view of an optical fiber tape unit according to the present invention, in which (A) is a structure in which four optical fiber ribbons integrated with four optical fibers are used and connected by a connecting resin; (B) is one in which two optical fiber ribbons, in which two optical fibers are integrated, are connected by a connecting resin. FIG. 14 shows a conventional example of an optical fiber ribbon, where (A) is a plan view and (B) is a cross-sectional view. FIG. 15 shows a conventional example of a split optical fiber ribbon.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Optical fiber ribbon 2 Connection resin 2a Flat part 3 Optical fiber 4 Integration resin 4a Flat part 5 Glass fiber 6 Protection resin 7 Coloring resin

Claims (8)

A plurality of optical fiber ribbons in which a plurality of optical fibers are arranged in parallel, the plurality of optical fibers are integrated with resin over the entire length, are arranged in parallel, and the plurality of optical fiber ribbons are connected by a connecting resin. An optical fiber tape unit,
When the maximum value of the thickness of the optical fiber ribbon is T ₁ (μm) and the outer diameter of the optical fiber is d (μm), an optical fiber ribbon that satisfies T ₁ ≦ d + 25 (μm) The optical fiber tape unit used. The optical fiber tape unit according to claim 1,
An optical fiber tape unit in which a trough is formed by the connecting resin according to a depression between adjacent optical fiber ribbons. An optical fiber tape unit according to claim 2,
When T ₁ the maximum thickness of the optical fiber _ribbon, the thickness at the valley was g _2, the optical fiber ribbon unit is g ₂ ≦ T _1. The optical fiber tape unit according to any one of claims 1 to 3,
An optical fiber tape unit in which the connecting resin covers and connects the entire circumference of the plurality of optical fiber ribbons. The optical fiber tape unit according to any one of claims 1 to 3,
An optical fiber tape unit in which the plurality of optical fiber ribbons are connected by the connecting resin in a state where a part of the optical fiber ribbon is exposed. The optical fiber tape unit according to any one of claims 1 to 3,
An optical fiber tape unit in which the connecting resin is provided only in a recess formed by optical fiber tape cores. The optical fiber tape unit according to any one of claims 1 to 6,
An optical fiber tape unit using an optical fiber ribbon in which adjacent optical fibers in the optical fiber ribbon are in contact with each other and integrated.   The optical fiber cable which concentrated the optical fiber tape unit of any one of Claims 1-7.

Images