JP4040633B2 - Optical cable - Google Patents

Description

  The present invention relates to an optical cable used as an optical drop cable, an optical indoor cable, or the like for drawing and wiring from a wiring system cable to a subscriber's house such as a building or a general house.

  In recent years, with the spread of communication services such as the Internet, FTTH (Fiber To The Home) connecting all sections from a communication carrier to a subscriber's home with optical fiber has been rapidly expanding. In such FTTH, the optical wiring network in the vicinity of the subscriber's home is generally an overhead wiring using a power pole, and the main method is to drop the wiring cable from the wiring pole to the subscriber's home using an optical drop cable. Has been adopted.

  FIG. 7 shows an example of such an optical drop cable. As shown in the figure, this optical drop cable has two single-core optical fiber cores 1 sandwiched between strength members 2 and 2 on both sides and a support line 3 on one side. The outer periphery 4 has a structure in which a thermoplastic resin such as polyethylene is collectively extruded and coated on the outer periphery. A connecting portion (neck portion) 7 that divides the cable into a supporting wire portion 5 and a cable portion 6 is provided between the supporting wire 3 and the strength member 2 of the cable. Notches 8 and 8 having a V-shaped cross-section for tearing are provided at substantially central portions of the upper and lower surfaces.

  When drawing such an optical drop cable into a subscriber's house, the cable part 6 is separated from the support line part 5 and pulled into the interior, and then wired as it is, or in a termination box attached to the building wall. A method is used in which the cable portion 6 separated from the support wire portion 5 is connected to the optical indoor cable and is drawn indoors. Recently, a method of installing the latter termination box has been widely used with emphasis on the indoor landscape. This is because optical drop cables use black resin with carbon black blended with polyethylene, etc. in consideration of weather resistance, while optical indoor cables are colored with a colorant other than black. This is because a good non-black resin is used and a good indoor landscape can be obtained.

  However, such a beautiful optical indoor cable is poor in weather resistance, so it has been necessary to take measures such as attaching a protective cover to the portion exposed outdoors.

  Under these circumstances, a good landscape during indoor wiring is guaranteed, and there is no need to take measures such as wearing a protective cover for outdoor wiring, as well as good weather resistance and reliability. There is a demand for an optical drop cable that enables highly reliable outdoor wiring and that provides a good landscape when indoor wiring is performed.

  By the way, an optical cable having a two-layer structure of an outer sheath 4 that collectively covers the optical fiber core wire 1 and the strength members 2 and 2 as shown in FIG. (For example, refer to Patent Document 1). By providing a coating 4b with good wear resistance on the outside of the coating 4a made of a flame retardant polyolefin having excellent inner flame retardancy and leadability but poor wear resistance, the respective characteristics of both coatings 4a and 4b can be obtained. They complement each other. In this optical cable, the tearing notches 8 and 8 are provided on the surface of the outer coating 4b so that the tips thereof reach the inner coating 4a.

However, as described above, a good landscape can be obtained for indoor wiring, and it is not necessary to take protective measures such as wearing a protective cover for outdoor wiring. A good and reliable outdoor wiring is possible, and an optical drop cable that can provide a good landscape has not been obtained yet.
JP 2004-205979 A

  The present invention has been made in response to the above-described problems of the prior art, and it is necessary to take a countermeasure such as providing a good landscape when indoor wiring is performed and installing a protective cover when outdoor wiring is performed. Provides an optical cable that is useful as an optical indoor cable, or an optical cable that can be used for outdoor wiring with good weather resistance and high reliability. The purpose is to do.

To achieve the above object, an optical cable of the present invention is a cable used for an optical indoor cables or optical drop cables, at a single-fiber optical fiber, the distance on both sides of the single-core optical fiber In an optical cable comprising first and second strength members arranged in parallel and a jacket covering them all together, the jacket is made of an inner coating made of non-black resin and a black resin peelable from the inner coating. is a two-layer structure of the outer coating of the inner coating surface inner coating tear notch is provided on the, outer covering tear notch is provided on the outer covering of the surface except the upper inner cover tear notch, and , the single core optical fiber and said first and second strength member and said outer covering tear notch is configured to parallel substantially coplanar It is characterized in that there.

  According to the optical cable of the present invention, a good landscape can be obtained in indoor wiring, and highly reliable wiring can be performed without attaching a protective cover or the like in outdoor wiring.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a cross-sectional view showing a first embodiment of the optical cable of the present invention.

  The optical cable 101 of this embodiment is used as an optical drop cable for drawing and wiring from a wiring cable installed between utility poles to a subscriber's house such as a building or a general house. And a connecting portion 30 for connecting them.

  The cable unit 10 is arranged in parallel with a distance between the two single-core optical fiber cores 11 and on both sides of the single-core optical fiber core wires 11 so that their centers are located on substantially the same plane. A first and second strength members 12a and 12b made of steel wire, glass fiber reinforced plastic, aramid fiber reinforced plastic, and the like, and a two-layer outer cover 15 made up of an inner coating 13 and an outer coating 14 that collectively coat them. It has. Both the inner coating 13 and the outer coating 14 have an oval cross section.

  On the other hand, the support wire portion 20 is composed of a support wire 21 made of a steel wire or the like, and a sheath 22 that is integrally coated with the outer sheath 14 of the cable portion 10 and the connecting portion 30 on the outer periphery thereof. The covering 22 has a circular cross section.

And in this embodiment, the inner coating 13 of the jacket 15 of the cable portion 10 is formed of a polyolefin-based non-black resin, and the outer coating 14, the connecting portion 30, and the coating 22 of the support wire portion 20 are It is formed of a black resin.
That is, the inner coating 13 is formed of a polyolefin resin such as polyethylene or polypropylene, a polyolefin elastomer resin, or a resin in which a colorant other than black, such as cream, yellow, or blue, is added to these resins. And therefore has a good aesthetic. On the other hand, the coating 22 of the outer coating 14, the connecting portion 30, and the support wire portion 20 is made of a polyolefin resin such as polyethylene and polypropylene, a thermoplastic resin such as a vinyl chloride resin, a polyamide resin, and a polyurethane resin blended with carbon black. Although it is formed and exhibits a black color, it is inferior in aesthetics, but has good weather resistance. These resins may contain a flame retardant and other additives as long as the effects of the present invention are not impaired. Examples of the polyolefin resin include polyethylene-polypropylene, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, ethylene-propylene copolymer, and the like.

  In addition, a pair of cross-sectional V-shapes are provided on the upper surface and the lower surface of the inner coating 13 where the single-core optical fiber core 11 is located so that the single-core optical fiber core 11 can be easily taken out during cable terminal processing. Inner coating tearing notches 16a, 16b are provided on the mold, and a pair of V-shaped outer coating tearing notches 17a, 17b are provided on the surface of the outer coating 14. One outer covering tear notch 17a is closer to the support line 21 than the central portion of the upper surface of the outer covering 13, and the other outer covering tear notch 17b is opposite to the support line 21 from the central portion of the lower surface of the outer covering 13. It is provided near. The outer covering tear notches 17a and 17b are not particularly limited as long as the outer covering 14 can be torn and the positions other than the inner covering tear notches 16a and 16b are excluded. That is, it is only necessary that the outer coating 14 is formed at a position where only the outer coating 14 is selectively torn when the outer coating 14 is torn from the outer coating tearing notches 17a and 17b.

  In the optical cable 101 of the present embodiment, the outer cover 15 of the cable portion 10 has a two-layer structure of the inner cover 13 and the outer cover 14, and the outer cover 14 can be selectively torn off the outer cover 14. Since the tearing notches 17a and 17b are provided, the cable part 10 is separated from the support line part 20 after being pulled down from the wiring cable hung on the power pole to the subscriber's house, and is then drawn indoors. It is possible to perform indoor wiring in a state in which only the inner covering 13 is covered by tearing and removing only the tearing notches 17a and 17b. Since the inner coating 13 is formed of non-black resin as described above, it is possible to perform wiring with a good scenery. On the other hand, until the cable is drawn indoors, the outer coating 14, the coating 22 of the support wire portion 20, the connecting portion 30, and the surface of the cable are all covered with a coating made of a black resin having good weather resistance. High outdoor wiring is possible.

In this embodiment, when forming the outer covering tearing notches 17a and 17b, the optical fiber core wire 11 is not positioned on the extension lines (indicated by L ₁ and L ₂ in FIG. 1) of the respective tips. Alternatively, it is preferable that inclusions (in the example of FIG. 1, the first and second strength members 12a and 12b) other than the jacket 15 be positioned between the optical fiber core wire 11. By comprising in this way, damage to the optical fiber core wire 11 by a semi (especially Kumazemi) egg-laying tube can be prevented. That is, the outer covering tearing notches 17a and 17b are formed on the surface of the outer jacket 15 and have a V-shaped cross section, so that a semi-vibrating tube is very easily inserted, and an extension line L ₁ at the tip thereof. If the optical fiber core wire 11 is disposed on the L ₂ without any inclusions other than the jacket 15, the optical fiber core wire 11 may be damaged by the egg-laying tube and possibly broken. In forming the outer covering tearing notches 17a and 17b, the optical fiber core wire 11 is not positioned on the extension lines L ₁ and L ₂ at the respective ends, or even if it is positioned, By making inclusions other than the jacket 15 intervene between them, it is possible to prevent the occurrence of such damage caused by the cicada oviposition tube.

  In the present invention, instead of forming the outer covering tearing notches 17a and 17b, a tearing string 18 made of polyester resin, aramid fiber, or the like may be embedded in the outer covering 14, as shown in FIG.

  That is, FIG. 2 is a cross-sectional view showing a modification of the first embodiment. The optical cable 102 shown in this example is the same as the optical cable 101 shown in FIG. 1 except that the outer covering tear notches 17a and 17b are not formed and the tear string 18 is embedded in the outer covering 14. It is constituted similarly.

  Also in the optical drop cable 102 configured as described above, the outer cover 13 of the cable portion 10 has a two-layer structure of the inner covering 13 and the outer covering 14, and the tearing strap 18 is embedded in the outer covering 14. Therefore, after being pulled down from the wiring cable interfering with the utility pole to the subscriber's house, the cable portion 10 is separated from the support wire portion 20 and drawn indoors, and then only the outer covering 14 is removed by tearing with the tear string 18. In addition, indoor wiring can be performed in a state where only the inner covering 13 is covered. Since the inner coating 13 is formed of a non-black resin, it is possible to perform wiring with good scenery. On the other hand, until the cable is drawn indoors, the outer coating 14, the coating 22 of the support wire portion 20, the connecting portion 30, and the surface of the cable are covered with a coating made of a black resin having a good weather resistance. High outdoor wiring is possible.

  In this example, the outer coating tearing notches 17a and 17b are not provided on the surface of the outer coating 14, so that the semi-vibrating tube is not easily damaged.

  The position where the tear string 18 is embedded is preferably within the notches 16a and 16b for inner coating tearing from the viewpoint of easy removal of the outer coating 14 and stability of the shape during cable manufacture. In this case, the tear string 18 may be embedded only in one of the inner covering tear notches 16a and 16b, or may be embedded in both of them.

  Next, another embodiment of the present invention will be described.

  FIG. 3 is a cross-sectional view according to the second embodiment of the present invention, and parts common to FIG.

  The optical cable 103 according to the present embodiment is used as a so-called optical indoor cable, in which an optical fiber drawn to a subscriber's home using an optical drop cable is drawn into the subscriber's home and wired indoors. The optical drop cable is connected in a termination box attached to the wall surface of the subscriber's house. The optical cable 103 can also be used as an underground optical drop cable laid in the basement.

  As shown in FIG. 3, this optical cable 103 has the same configuration as that of the optical drop cable 101 shown in FIG. 1 except that outer coating tearing notches 17a and 17b are provided at substantially the center of both side surfaces of the outer coating 14. The configuration is almost the same as the cable portion 10.

  That is, the two single-core optical fiber cores 11 and the first and second optical fibers 11 arranged in parallel at an interval so that the centers of the single-core optical fiber core wires 11 are located on substantially the same plane on both sides of the single-core optical fiber core wire 11. A second tensile strength member 12a, 12b and a two-layered outer cover 15 comprising an inner coating 13 and an outer coating 14 for covering them all together, both of the inner coating 13 and the outer coating 14 having an oval cross section. It is formed into a shape. The inner coating 13 is made of a polyolefin-based non-black resin, and the outer coating 14 is made of a black resin. In addition, a pair of V-shaped inner coating tearing notches 16a and 16b are provided on the upper surface and the lower surface of the inner coating 13 where the single-core optical fiber core wire 11 is located. Outer coating tearing notches 17a and 17b are provided at substantially central portions of both side surfaces.

  In the optical cable 103 according to the present embodiment, the outer cover 15 has a two-layer structure of an inner cover 13 and an outer cover 14, and the outer cover 14 can be torn the outer cover 14 selectively. 17b, so that after pulling into the subscriber's house from the termination box attached to the building wall, only the outer covering 14 is removed by tearing the notch 17b for tearing, and only the inner covering 13 is covered. Indoor wiring can be performed. Since the inner coating 13 is formed of non-black resin as described above, it is possible to perform wiring with a good scenery. On the other hand, since the outer coating 14 made of a black resin with good weather resistance is applied until it is drawn indoors, it is not necessary to take measures such as mounting a conventional protective cover.

  As in the case of the first embodiment, the outer covering tear notches 17a and 17b are selectively used only when the outer covering 14 is torn when the outer covering tear notches 17a and 17b are used as starting points. It may be formed at a position where it can be torn, and is not particularly limited to the example of the drawings.

Also in this embodiment, when forming the outer covering tearing notches 17a and 17b, the optical fiber core wire 11 is not positioned on the extension lines L ₁ and L ₂ at the respective ends, or the optical fiber core wire 11 It is preferable that inclusions other than the outer jacket 15 be positioned between the optical fibers on the extension lines L ₁ and L ₂ at the tips of the outer coating tearing notches 17a and 17b in the example of FIG. Although the core wire 11 is located, the first and second strength members 12a and 12b are interposed between the single-core optical fiber core wire 11). By comprising in this way, the damage of the single core optical fiber core wire 11 by a semi-laying oviduct can be prevented.

  In the present invention, instead of forming the outer covering tear notches 17a and 17b, a tear string 18 made of polyester resin, aramid fiber or the like may be embedded in the outer covering 14, as shown in FIG.

  That is, FIG. 4 is a cross-sectional view showing a modification of the second embodiment. The optical cable 104 shown in this example is not formed with the outer coating tearing notches 17a and 17b, and the optical cable 103 shown in FIG. It is constituted similarly.

  Also in the optical cable 104 configured as described above, the outer cover 15 has a two-layer structure of the inner cover 13 and the outer cover 14, and the outer cover 14 can tear the outer cover 14 selectively. Since 18 is embedded, after being drawn into the subscriber's house from the termination box attached to the building wall, only the outer covering 14 is removed by tearing with the tear string 18 and only the inner covering 13 is covered. It can be performed. Since the inner coating 13 is formed of a non-black resin, it is possible to perform wiring with good scenery. On the other hand, since the outer coating 14 made of a black resin with good weather resistance is applied until it is drawn indoors, it is not necessary to take measures such as mounting a conventional protective cover.

  In this example, the outer coating tearing notches 17a and 17b are not provided on the surface of the outer coating 14, so that the semi-vibrating tube is not easily damaged.

  The position where the tear string 18 is embedded is preferably within the notches 16a and 16b for inner coating tearing from the viewpoint of easy removal of the outer coating 14 and stability of the shape during cable manufacture. In this case, the tear string 18 may be embedded only in one of the inner covering tear notches 16a and 16b, or may be embedded in both of them.

  FIG. 5 is a cross-sectional view according to the third embodiment of the present invention, and parts common to FIG.

  Similar to the optical cable shown in FIGS. 3 and 4, the optical cable 105 according to the present embodiment is a so-called optical fiber in which an optical fiber drawn to a subscriber's house using an optical drop cable is drawn into the subscriber's house and wired indoors. It is mainly used as an indoor cable.

  As shown in FIG. 5, this optical cable 105 includes two single-core optical fibers 11, and an aramid fiber, a polyarylate fiber, a polyparaphenylene benzbisoxazole (PBO) fiber, and the like provided around the optical fiber core wire 11. A cushioning material layer 19 made of tensile strength fibers and a jacket 15 having a circular cross section provided outside thereof are provided. The outer jacket 15 has a two-layer structure consisting of an inner coating 13 made of a polyolefin-based non-black resin and an outer coating 14 made of a black resin. The inner coating 13 includes a steel wire and a glass fiber reinforced plastic. The first and second strength members 12a and 12b made of aramid fiber reinforced plastic are embedded so as to be symmetrical with respect to the center of the cable. Further, inner coating tearing notches 16a and 16b having a V-shaped cross section are provided on the surface of the inner coating 13 at a position rotated by approximately 90 ° in the circumferential direction from each of the first and second strength members 12a and 12b. Furthermore, outer coating tearing notches 17a and 17b having a V-shaped cross section are also provided on the surface of the outer coating 14. The outer covering tear notches 17a and 17b are further rotated by about 90 ° in the circumferential direction from the inner covering tear notches 16a and 16b, that is, the outer covering 14 on the first and second strength members 12a and 12b. It is provided on the surface.

  In the optical cable 105 of the present embodiment, the outer cover 15 has a two-layer structure of an inner covering 13 and an outer covering 14, and the tearing notch 17 a that can selectively tear the outer covering 14 on the outer covering 14. 17b is provided, and after pulling into the subscriber's house from the termination box attached to the building wall, only the outer covering 14 is removed by tearing with the tearing notches 17a and 17b, and only the inner covering 13 is covered. Indoor wiring can be performed in the state. Since the inner coating 13 is made of a non-black resin, it is possible to perform wiring with good aesthetics. On the other hand, since the outer coating 14 made of a black resin with good weather resistance is applied until it is drawn indoors, it is not necessary to take measures such as mounting a conventional protective cover.

  Also in this embodiment, the outer covering tear notches 17a and 17b can selectively tear only the outer covering 14 when the outer covering 14 is torn starting from the outer covering tear notches 17a and 17b. As long as it is formed in such a position, it is not particularly limited to the example of the drawings.

Further, in forming the outer covering tearing notches 17a and 17b, the optical fiber core wire 11 is not positioned on the extension lines L ₁ and L ₂ at the respective ends, or the jacket is formed between the outer fiber tear wire 11 and the optical fiber core wire 11. It is preferable that inclusions other than 15 are located (in the example of FIG. 5, the optical fiber core 11 is located on the extension lines L ₁ and L ₂ at the tips of the outer covering tearing notches 17a and 17b. However, the first and second strength members 12a and 12b and the buffer material layer 19 are interposed between the single-core optical fiber core 11). By comprising in this way, the damage of the single core optical fiber core wire 11 by a semi-laying oviduct can be prevented.

  Further, instead of forming the outer covering tearing notches 17a and 17b, as shown in FIG. 6, a tearing string 18 made of polyester resin, aramid fiber or the like may be embedded in the outer covering 14.

  That is, FIG. 6 is a cross-sectional view showing a modification of the third embodiment. The optical cable 106 shown in this example is the same as the optical cable 105 shown in FIG. 5 except that the outer covering tearing notches 17a and 17b are not formed and the tear string 18 is embedded in the outer covering 14. It is constituted similarly.

  Also in the optical cable 106 configured in this manner, the outer cover 15 has a two-layer structure of the inner covering 13 and the outer covering 14, and the outer covering 14 can be torn the outer covering 14 selectively. Since 18 is embedded, after being pulled into the subscriber's house from the termination box attached to the building wall, only the outer covering 14 is torn and removed by the tear string 18 and only the inner covering 13 is covered. It can be performed. Since the inner coating 13 is made of a non-black resin, it is possible to perform wiring with good aesthetics. On the other hand, since the outer coating 14 made of a black resin with good weather resistance is applied until it is drawn indoors, it is not necessary to take measures such as mounting a conventional protective cover.

  In this example, the outer coating tearing notches 17a and 17b are not provided on the surface of the outer coating 14, so that the semi-vibrating tube is not easily damaged.

  The position where the tear string 18 is embedded is preferably within the notches 16a and 16b for inner coating tearing from the viewpoint of easy removal of the outer coating 14 and stability of the shape during cable manufacture. In this case, the tear string 18 may be embedded only in one of the inner covering tear notches 16a and 16b, or may be embedded in both of them.

  As the single-core optical fiber core wire 11 used in the present invention, for example, one in which the outer periphery of the optical fiber is coated with silicone resin, ultraviolet curable resin, or the like, and the outer periphery is further coated with polyamide resin or the like can be cited. However, the present invention is not limited to these. Moreover, the number to accommodate is not specifically limited, either 1 or 3 or more. Furthermore, instead of the single-core optical fiber core 11, an optical fiber tape core wire in which a plurality of optical fiber strands are arranged in parallel and the outer periphery thereof is collectively covered may be used.

  Next, examples of the present invention will be described, but the present invention is not limited to the following examples.

Example 1
An optical cable having the structure shown in FIG. 3 was manufactured.
First, two UV-curable resin-coated single-core optical fibers 11 having an outer diameter of 250 μm and two strength members 12a and 12b made of G-FRP (glass fiber reinforced plastic) having an outer diameter of 0.4 mm. As shown in FIG. 3, it is introduced into the first extruder in a parallel state, and polyethylene blended with a cream colorant is batch-extruded on the outer periphery thereof, and a cream-colored inner coating tear notch 16a is formed on the surface. , 16b was formed. Further, this coated wire is introduced into a second extruder, and polyethylene coated with carbon black on the outer periphery thereof is collectively extrusion coated to have outer coated tear notches 17a and 17b on the surface, and an outer coating of about 0.5 mm thickness. 14 was manufactured, and an optical cable having a width of about 4 mm and a height of about 3 mm was manufactured.

Example 2
An optical cable having the structure shown in FIG. 5 was manufactured.
First, two aramid fibers are vertically attached to the outer periphery of two UV-curable resin-coated single-core optical fibers 11 having an outer diameter of 250 μm, and two G-FRPs (glass fiber reinforced plastics) having an outer diameter of 0.4 mm. As shown in FIG. 5, the tensile strength members 12a and 12b are introduced into the first extruder, and the outer periphery of the tensile strength members 12a and 12b is batch-extruded with polyethylene blended with a cream colorant, so that the cream-colored surface is covered. An inner coating 13 having inner coating tear notches 16a, 16b was formed. Further, this coated wire is introduced into a second extruder, and polyethylene coated with carbon black on the outer periphery thereof is collectively extrusion coated to have outer coated tear notches 17a and 17b on the surface, and an outer coating of about 0.5 mm thickness. 14 was produced, and an optical cable having an outer diameter of about 4 mm was manufactured.

  About each obtained optical cable, while measuring transmission loss ((lambda) = 1550nm), a heat cycle test (-30 degreeC-+70 degreeC, 3 cycles) is performed, the increase amount of transmission loss ((lambda) = 1550nm) is measured, Its temperature characteristics were evaluated. Further, the outer coating 14 was torn starting from the outer coating tearing notches 17a and 17b, and the removal property thereof, that is, the taking-out property of the inner coated wire was examined. These results are shown in Table 1.

表１からも明らかなように、各光ケーブルは、いずれも十分に実用可能な伝送特性、温度特性を有するとともに、外側被覆１４を容易に除去することができることが確認された。

As is apparent from Table 1, it was confirmed that each optical cable has sufficiently practical transmission characteristics and temperature characteristics, and the outer coating 14 can be easily removed.

It is sectional drawing which shows the optical cable which concerns on the 1st Embodiment of this invention. It is sectional drawing which shows the modification of 1st Embodiment. It is sectional drawing which shows the optical cable which concerns on the 2nd Embodiment of this invention. It is sectional drawing which shows the modification of 2nd Embodiment. It is sectional drawing which shows the optical cable which concerns on 3rd Embodiment. It is sectional drawing which shows the modification of 3rd Embodiment. It is sectional drawing which shows an example of the conventional optical cable. It is sectional drawing which shows the other example of the conventional optical cable.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Cable part, 11 ... Single-core optical fiber core wire, 12a, 12b ... 1st and 2nd strength member, 13 ... Outer coating, 14 ... Inner coating, 15 ... Outer coating, 16a, 16b ... For inner coating tearing Notches, 17a, 17b ... Notches for outer covering tearing, 18 ... Tear string, 19 ... Buffer layer, 20 ... Supporting wire portion, 21 ... Supporting wire, 22 ... Covering, 30 ... Connecting portion, 101-106 ... Optical cable

Claims (3)

A cable for use as an optical indoor cables or optical drop cables, and single-fiber optical fiber, the first and second strength members which are parallel spaced on both sides of the single-core optical fiber In an optical cable having a jacket for covering them all together,
The envelope is a two-layer structure of an outer coating of peelable black resin from the inside coated with the inner coating of the non-black resin, the inner covering tear notch is provided on a surface of said inner coating, said inner coating An outer coating tear notch is provided on a surface of the outer coating except on the tear notch , and the single-core optical fiber core, the first and second strength members, and the outer coating tear notch are approximately An optical cable characterized by being arranged in parallel on the same plane . Wherein the outer covering tear notch, optical cable according to claim 1, wherein the cross section is V-shaped. The single-core optical fiber buffer material layer around is provided for, according to claim 1 or 2 optical cable, wherein the jacket is provided on its outer side.

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