JP2010164692A - Optical fiber cable - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an intermittent fixing configuration that imparts a proper side pressure to an optical fiber in a groove and that obtains superior transmission characteristics. <P>SOLUTION: The optical fiber cable 1 includes: one groove slot rod 7 having one groove 5 in which one or more optical fibers 3 are twined and stored inside; a vertically attached tape 13 vertically attached in a manner covering the opening 11 of the groove 5 of this slot rod 7; and a sheath 15 for covering the vertically attached tape 13 and the periphery of the slot rod 7. With the purpose of intermittently fixing the one or more optical fibers 3 in the groove 5 of the slot rod 7, a UV fixing material 19 is installed by intermittently fixing UV resin 17 in advance in the longitudinal direction on the vertically attached tape 13. A relationship between the pitch (P<SB>UV</SB>) of the UV fixing material 19 and the twisting pitch (P<SB>F</SB>) of the one or more optical fibers 3 is configured such that the pitch P<SB>UV</SB>of the UV fixing material is greater than the fiber twisting pitch P<SB>F</SB>of the optical fiber(s) 3. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an optical fiber cable, and more particularly, one or more optical fibers are twisted and housed in a groove of a single groove slot rod, and the optical fiber in the groove is covered when the periphery of the slot rod is covered with a sheath. The present invention relates to an optical fiber cable fixed intermittently.

  As a conventional optical fiber cable, the periphery of a slot rod (for example, a C-type slot) having one groove for accommodating the optical fiber is covered with an eccentric sheath. There exists patent document 1 as what corresponds to this.

  Conventionally, when manufacturing optical fiber cables, especially when one or more optical fibers are accommodated and cabled, the optical fibers are twisted at a constant pitch to ensure a certain excess length ratio. can do. It is a well-known technique to obtain good transmission characteristics by relaxing the distortion of the optical fiber due to the effects of bending, temperature expansion and contraction, etc. throughout the twist.

  For such optical fibers that are twisted together, there is an intermittent fixing method that applies a lateral pressure that does not deteriorate the transmission characteristics while suppressing the movement of the optical fiber using intermittently arranged intermittent fixing materials. In Patent Document 2, an optical fiber is fixed using an intermittent fixing material, and the length is specified as shown below.

  (1) The intermittent fixing length is not less than 10 mm and not more than the sheath removal length.

  (2) The intermittent fixing length is not less than 10 mm and not more than the aerial closure length.

  (3) The intermittent fixing length is 10 mm or more and the underground closure length or less.

JP 2008-76898 A JP 2004-191506 A

  By the way, in the intermittent fixing method, if the lateral pressure applied by the intermittent fixing material is too large with respect to one pitch of the optical fiber twist, the above-described distortion relaxation effect is reduced, and there is a possibility that transmission characteristics are deteriorated. Furthermore, when the optical fiber moves in the groove, a pull-in or pop-out phenomenon may occur at the end portion of the optical fiber. However, in the optical fiber cable of Patent Document 2, any provision of the intermittent fixing length is centered on workability, and the relationship between the twisted length of the optical fiber and the intermittent fixing material for obtaining good transmission characteristics is described. It is not done.

  An object of the present invention is to achieve an intermittently fixed configuration in which an appropriate lateral pressure is applied when an optical fiber accommodated in a groove is intermittently fixed and good transmission characteristics can be obtained.

In order to solve the above-described problems, an optical fiber cable of the present invention includes a one-groove slot rod having one groove in which one or more optical fibers are twisted and housed, and an opening portion of the groove of the slot rod. In an optical fiber cable composed of a longitudinally attached tape so as to cover the sheath, and a sheath covering the longitudinally attached tape and the periphery of the slot rod,
In order to intermittently fix one or more optical fibers in the slot of the slot rod, UV curable resin is intermittently fixed in advance in the longitudinal direction to the longitudinal tape, and a UV fixing material is provided.
The relationship between the pitch of the UV fixing material and the twist pitch of the one or more optical fibers is as follows:
The pitch of the UV fixing material is greater than the fiber twist pitch of the optical fiber.

The optical fiber cable according to the present invention also includes a one-groove slot rod having one groove in which one or more optical fibers are twisted and housed inside, and a longitudinally attached so as to cover the opening of the groove of the slot rod. In an optical fiber cable comprising an attachment tape, and a longitudinal attachment tape and a sheath covering the periphery of the slot rod,
In order to intermittently fix one or more optical fibers in the slot of the slot rod, UV curable resin is intermittently fixed in advance in the longitudinal direction to the longitudinal tape, and a UV fixing material is provided.
The relationship between the length of the UV fixing material and the twist pitch of the one or more optical fibers is:
Length of UV fixing material ≦ fiber twist pitch of optical fiber / 2
It is characterized by being.

The optical fiber cable according to the present invention also includes a one-groove slot rod having one groove in which one or more optical fibers are twisted and housed inside, and a longitudinally attached so as to cover the opening of the groove of the slot rod. In an optical fiber cable comprising an attachment tape, and a longitudinal attachment tape and a sheath covering the periphery of the slot rod,
In order to intermittently fix one or more optical fibers in the slot of the slot rod, UV curable resin is intermittently fixed in advance in the longitudinal direction to the longitudinal tape, and a UV fixing material is provided.
The relationship between the pitch of the UV fixing material and the twist pitch of the one or more optical fibers is as follows:
The pitch of the UV fixing material> the fiber twist pitch of the optical fiber, and the relationship between the length of the UV fixing material and the twist pitch of the one or more optical fibers is
Length of UV fixing material ≦ fiber twist pitch of optical fiber / 2
It is characterized by being.

The optical fiber cable according to the present invention also includes a one-groove slot rod having one groove in which one or more optical fibers are twisted and housed inside, and a longitudinally attached so as to cover the opening of the groove of the slot rod. In an optical fiber cable comprising an attachment tape, and a longitudinal attachment tape and a sheath covering the periphery of the slot rod,
In order to intermittently fix the plurality of optical fibers in the slot of the slot rod, the adhesive tape is intermittently fixed in advance in the longitudinal direction of the longitudinal tape, and an adhesive fixing material is provided.
The relationship between the pitch of the adhesive fixing material and the twist pitch of the one or more optical fibers is as follows:
Pitch of adhesive fixing material> Fiber twist pitch of optical fiber / 2
It is characterized by being.

The optical fiber cable according to the present invention also includes a one-groove slot rod having one groove in which one or more optical fibers are twisted and housed inside, and a longitudinally attached so as to cover the opening of the groove of the slot rod. In an optical fiber cable comprising an attachment tape, and a longitudinal attachment tape and a sheath covering the periphery of the slot rod,
In order to intermittently fix the plurality of optical fibers in the slot of the slot rod, the adhesive tape is intermittently fixed in advance in the longitudinal direction of the longitudinal tape, and an adhesive fixing material is provided.
The relationship between the length of the adhesive fixing material and the twist pitch of the one or more optical fibers is as follows:
Length of adhesive fixing material ≦ Fiber twist pitch of optical fiber / 2
It is characterized by being.

The optical fiber cable according to the present invention also includes a one-groove slot rod having one groove in which one or more optical fibers are twisted and housed inside, and a longitudinally attached so as to cover the opening of the groove of the slot rod. In an optical fiber cable comprising an attachment tape, and a longitudinal attachment tape and a sheath covering the periphery of the slot rod,
In order to intermittently fix one or more optical fibers in the slot of the slot rod, an adhesive resin is intermittently fixed in advance in the longitudinal direction to the longitudinal tape, and an adhesive fixing material is provided.
The relationship between the pitch of the adhesive fixing material and the twist pitch of the one or more optical fibers is as follows:
The relationship between the pitch of the adhesive fixing material> the fiber twist pitch of the optical fiber, and the length of the adhesive fixing material and the twist pitch of the one or more optical fibers (fiber twist pitch),
Length of adhesive fixing material ≦ Fiber twist pitch of optical fiber / 2
It is characterized by being.

  As can be understood from the means for solving the above problems, according to the present invention, the relationship between the pitch of the UV fixing material and the fiber twist pitch of the optical fiber is expressed as follows: UV fixing material pitch> optical fiber fiber By setting the twist pitch, good loss temperature fluctuation characteristics can be obtained at a wavelength of 1.55 μm that is normally used in transmission lines. Therefore, it is possible to provide an optical fiber cable that eliminates the pulling and jumping of the optical fiber into the groove of the slot rod structure and does not impair the transmission loss characteristics.

  Further, according to the present invention, the relationship between the length of the UV fixing material and the fiber twist pitch of the optical fiber is set to the length of the UV fixing material ≦ the fiber twist pitch of the optical fiber / 2, so that it is used in the normal transmission line. Good loss temperature fluctuation characteristics can be obtained at a wavelength of 1.55 μm. Therefore, it is possible to provide an optical fiber cable that eliminates the pulling and jumping of the optical fiber into the groove of the slot rod structure and does not impair the transmission loss characteristics.

  According to the present invention, the relationship between the pitch of the UV fixing material and the fiber twist pitch of the optical fiber is such that the pitch of the UV fixing material> the fiber twist pitch of the optical fiber, and the length of the UV fixing material and the length of the optical fiber In relation to the fiber twist pitch, the length of the UV fixing material ≦ the fiber twist pitch of the optical fiber / 2, and in addition to the wavelength of 1.55 μm normally used in the transmission line, the wavelength of 1.625 μm Also good loss temperature fluctuation characteristics can be obtained. Therefore, it is possible to provide an optical fiber cable that eliminates the pulling and jumping of the optical fiber into the groove of the slot rod structure and does not impair the transmission loss characteristics.

  Further, according to the present invention, the relationship between the pitch of the adhesive fixing material and the fiber twist pitch of the optical fiber is such that the pitch of the adhesive fixing material is greater than the fiber twist pitch of the optical fiber. Good loss temperature fluctuation characteristics can be obtained at a wavelength of .55 μm. Therefore, it is possible to provide an optical fiber cable that eliminates the pulling and jumping of the optical fiber into the groove of the slot rod structure and does not impair the transmission loss characteristics.

  Further, according to the present invention, the relationship between the length of the adhesive fixing material and the fiber twist pitch of the optical fiber is 1.55 μm which is normally used in a transmission line by setting the adhesive fixing material length ≦ the fiber twist pitch / 2. It is possible to obtain a good loss temperature fluctuation characteristic at a wavelength of. Therefore, it is possible to provide an optical fiber cable that eliminates the pulling and jumping of the optical fiber into the groove of the slot rod structure and does not impair the transmission loss characteristics.

  According to the present invention, the relationship between the pitch of the adhesive fixing material and the fiber twist pitch of the optical fiber is such that the pitch of the adhesive fixing material> the fiber twist pitch of the optical fiber, and the adhesive fixing material length and the fiber twist pitch By making the relationship of adhesive fixing material length ≦ fiber twist pitch / 2, in addition to the wavelength of 1.55 μm normally used in transmission lines, good loss temperature fluctuation characteristics are obtained even at a wavelength of 1.625 μm. be able to. Therefore, it is possible to provide an optical fiber cable that eliminates the pulling and jumping of the optical fiber into the groove of the slot rod structure and does not impair the transmission loss characteristics.

It is sectional drawing of the optical fiber cable of embodiment of this invention. It is sectional drawing of the arrow II-II line | wire of FIG. It is a schematic perspective view which shows the manufacturing method of the optical fiber cable of embodiment of this invention. It is the schematic diagram showing the twisted state of the optical fiber of FIG. 1, and the arrangement | positioning state of UV fixing material. It is explanatory drawing which classified the data of Table 1 into classification. It is a graph of the cable characteristic corresponding to (Formula 1) at a wavelength of 1.55 μm. It is a graph of the cable characteristic which does not correspond to (Formula 1) in the wavelength of 1.55 micrometer. It is a graph of the cable characteristic corresponding to (Formula 2) at a wavelength of 1.55 μm. It is a graph of the cable characteristics not corresponding to (Formula 2) at a wavelength of 1.55 μm. It is a graph of the cable characteristic applicable to (Formula 1) and (Formula 2) in the wavelength of 1.625 micrometers. It is a graph of the cable characteristic which does not correspond to (Formula 1) in the wavelength of 1.625 micrometers. It is a graph of the cable characteristic which does not correspond to (Formula 2) in the wavelength of 1.625 micrometers. It is a graph of the cable characteristic which does not correspond to (Formula 1) and (Formula 2) in the wavelength of 1.625 micrometers.

  Embodiments of the present invention will be described below with reference to the drawings.

  Referring to FIGS. 1 and 2, an optical fiber cable 1 according to this embodiment is a one-groove slot type optical fiber cable, and is a 1 for twisting one or more optical fibers 3 and accommodating them inside. A slot rod 7 provided with two grooves 5, a tensile member 9 (tension member) as an optical fiber protection filament embedded in the slot rod 7, and an opening of the slot 5 in the slot 5 11, and a longitudinally attached tape 13 that is vertically attached so as to cover 11, and an uneven thickness sheath 15 as a sheath that covers the periphery of the longitudinally attached tape 13 and the slot rod 7. Further, one or more optical fibers 3 in the groove 5 of the slot rod 7 are intermittently preliminarily coated with ultraviolet curable resin 17 (hereinafter simply referred to as “UV resin”) in the longitudinal direction of the longitudinal tape 13. It is fixed intermittently by a UV fixing material 19 formed by adhering. That is, the UV resin 17 is used as an intermittent fixing material.

  In addition, as a material of the vertical tape 13, a non-woven fabric, a water-absorbing non-woven fabric, a plastic tape such as a PET tape, and the like can be given. Further, as the UV resin 17, it is desirable to select a soft material that does not give a side pressure that deteriorates loss characteristics and can suppress optical fiber movement, that is, a material having a Young's modulus of 800 Mpa or less.

  Further, in this embodiment, as shown in FIG. 1, the slot rod 7 is a so-called “C-type slot” in which the groove 5 has a circular cross section, and one or more light beams are formed inside the groove 5. In FIG. 1, for example, ten four-fiber optical fiber ribbons as the optical fiber 3 are accommodated. The optical fiber 3 is not limited to the optical fiber ribbon, and an optical fiber, an optical fiber, or another form of optical fiber is used. Further, the cross-sectional shape of the groove 5 is not limited to a circular shape, but may be a U-shape or other cross-sectional shapes.

  Moreover, as said tensile body 9, it is extended | stretched in the longitudinal direction of the slot rod 7 in the thick part of the slot rod 7, and a steel wire, FRP, etc. can be used.

  The uneven thickness sheath 15 is made of a resin such as polyethylene resin, for example, and the sheath thickness on the opening 11 side of the groove 5 is relatively thicker than the sheath thickness on the opposite side to the opening 11 side of the groove 5. It has an eccentric sheath structure. The sheath is not limited to the above-described uneven thickness sheath 15, but may be a sheath having a substantially constant thickness.

  Next, a method for manufacturing the optical fiber cable 1 according to this embodiment will be described.

Referring also to FIG. 3, one or more optical fibers 3, that is, ten optical fiber ribbons as shown in FIG. Twisted in the direction. When the reference numerals (1) to (10) are attached to the ten optical fiber ribbons, one pitch of the optical fibers 3 is twisted as shown in FIG. The twisting pitch of the optical fiber 3 at this time is referred to as “fiber twisting pitch P _F ”.

  More specifically, the above-described stranded wire machine 21 includes, for example, a rotating body 25 provided with a rotating shaft 23 so as to be rotatable about the rotating shaft 23, and the rotation speed is controlled by a drive motor (not shown). It is the structure driven rotationally. Further, a plurality of optical fiber reels 27 in which the optical fiber 3 is wound in a roll shape are arranged on the rotary body 25 on the rotary shaft 23. In this embodiment, ten optical fiber reels 27 are arranged on the rotating body 25.

  Therefore, when the rotating body 25 rotates, the plurality of optical fibers 3 drawn from the plurality of optical fiber reels 27 rotate around the rotation shaft 23, so that the ten optical fibers 3 are gathered by the concentrating dies 29. It will be twisted in one direction at a point.

  Thereafter, the twisted optical fiber 3 is accommodated in the fiber assembly 31 in the groove 5 of the one-groove slot rod 7 (“C-type slot” in this embodiment).

  On the other hand, the vertically attached tape 13 is fed so that the surface in contact with the slot rod 7 is reversed in advance and the surface in contact with the slot rod 7 becomes the upper surface. The vertical tape 13 is intermittently jetted and supplied with UV resin 17 from a UV resin filling device 33 provided above, and the UV resin 17 is placed on the vertical tape 13 approximately in the center in the width direction. And intermittently applied in the longitudinal direction of the longitudinal tape 13. Immediately after that, each UV resin 17 on the vertical tape 13 is cured by the ultraviolet rays 37 irradiated from the UV lamp 35 provided in front of the vertical tape 13 in the feeding direction, and fixed to the vertical tape 13. The UV fixing material 19 is formed.

Referring to FIG. 4, in this embodiment, the pitch of the UV fixing material 19 is referred to as “UV fixing material pitch P _UV ”. That is, the UV fixing material pitch P _UV is a coating pitch of the UV resin 17 and is a distance from the head of the intermittently applied UV resin 17 to the head of the next UV resin.

The length of each UV fixing material 19 is referred to as “UV fixing material length L _UV ”. That is, the UV fixing material length L _UV is a coating dimension of the UV resin 17 and is a distance from the top to the end of the UV fixing material 19.

  As another method of irradiating ultraviolet rays, for example, a transparent resin tape that transmits ultraviolet rays 37 is used as the longitudinally attached tape 13, and the ultraviolet rays 37 are irradiated from the lower surface side of the longitudinally attached tape 13. The UV resin 17 can be fixed to the vertical tape 13 by passing through the vertical tape 13 and curing the UV resin 17.

  Then, the vertical tape 13 is reversed by the vertical tape reversing section 43 in the middle of being sent to the vertical tape collecting section 41 through the guide roller 39, so that the UV fixing material 19 fixed to the vertical tape 13 is directed downward. become. In other words, the vertical tape 13 is reversed so that the surface on which the UV fixing material 19 is placed contacts the slot rod 7.

  Next, when the one-slot slot rod 7 storing one or more optical fibers 3 in the groove 5 passes through the vertically-attached tape collecting portion 41, the above-mentioned vertically-attached tape 13 is formed in the groove 5 of the slot rod 7. Vertically attached so as to cover the opening 11. At this time, the UV fixing material 19 applied to the longitudinal tape 13 is pushed into the groove 5 of the slot rod 7. The UV fixing material 19 can be inserted into the groove 5 without resistance by being filled in advance so as to have a size equal to or smaller than the width of the groove 5 of the slot rod 7. Then, as shown in FIGS. 1 and 2, the plurality of optical fibers 3 inside the groove 5 of the slot rod 7 are intermittently fixed by the UV fixing material 19.

  As described above, in the intermittent fixing material filling method, the UV fixing material 19 is formed by applying and fixing the UV resin 17 intermittently on the vertical tape 13 in advance, and the vertical tape 13 is then attached. This is a method of pushing into the groove 5 of the slot rod 7.

  Next, the slotted rod 7 and the slotted rod 7 are placed in the extrusion head 47 of the extrusion molding machine 45 in a state where the slot 11 is vertically attached so that the opening 11 of the groove 5 is covered with the longitudinally attached tape 13. The optical fiber cable 1 is molded by being covered with an eccentric sheath 15 having an eccentric periphery and extruded.

Even if only the UV fixing material length L _UV (the coating length of the UV resin 17) is defined in the optical fiber cable 1, it is difficult to obtain good transmission characteristics. relationship and configuration of fiber twisting pitch P _F and UV fixed member 19 of the optical fiber 3 to be mounted on the optical fiber cable 1 is important.

That is, in the optical fiber cable 1 according to this embodiment, the UV resin 17 is used as an intermittent fixing material, and the UV fixing material pitch P _UV (application pitch of the UV resin 17) and the UV fixing material length L _UV (UV A test cable was manufactured by changing the resin 17 application dimension) and the fiber twist pitch P _F (twist pitch of the optical fiber 3). Further, as the optical fiber 3, one obtained by twisting 12 optical fiber strands having a diameter of 0.25 mm and 10 four-core tape core wires (40 fibers in total) were used. And the loss temperature fluctuation characteristic of each test cable was measured and evaluated. The results are as shown in Table 1.

Analysis of the Table 1, the pitch _{P UV} of UV fixing member, and the length _{L UV} of UV fixing material, the relationship between the fiber twist pitch _{P F} of the optical fiber 3 of the following (1) to (3) The street was found to be a condition for obtaining good transmission characteristics.

(1) Pitch _{P UV} relationships UV fixing material between the fiber twist pitch _{P F} of the pitch _{P UV} and optical fiber UV fixing material,
Fiber twist pitch _P F · · · · · · · of the pitch _{P UV>} optical fiber UV fixing material (Equation 1)
Need to be.

  It has been confirmed that the loss temperature fluctuation characteristics of the test cable corresponding to (Equation 1) are better than those of the test cable not corresponding to the same condition at the wavelength of 1.55 μm normally used in the transmission line. It was.

  The reason for this is that by twisting one or more optical fibers 3 at a constant pitch, a certain extra length ratio can be secured, and the entire twist is light due to the influence of bending, temperature expansion and contraction, etc. Although the distortion of the fiber 3 is alleviated, when the twisted optical fiber 3 is intermittently fixed by the UV fixing material 19, the lateral pressure is set so as not to deteriorate the transmission characteristics while suppressing the movement of the optical fiber 3. It is required to give. In this respect, if there is a lateral pressure applied by a plurality of intermittent fixing materials in one pitch of the optical fiber 3 twisted, the above-described distortion relaxation effect may be reduced, which may cause deterioration of transmission characteristics. (Formula 1) is a condition for avoiding this.

(2) For the same thought relationships described above (1) with fiber twist pitch _{P F} of length _{L UV} and optical fiber UV fixing member, UV fixing member length _{L UV} is
Length of UV fixing material L _UV ≦ Fiber twist pitch of optical fiber P _F / 2 (Equation 2)
Need to be.

  It is confirmed that the loss temperature fluctuation characteristics of the test cable corresponding to (Equation 2) are better than those of the test cable not corresponding to the same condition at the wavelength of 1.55 μm normally used in the transmission line. It was.

  This depends on the strain relaxation effect caused by twisting of the optical fiber 3, and in order to remove both compression and elongation strain, the optical fiber 3 fixed by the UV fixing material 19 is at the twisting angle. It shows that a free moving part of 180 ° or more is necessary.

(3) Relationship satisfying both the conditions of (Expression 1) and (Expression 2) described above The pitch P _UV of the UV fixing material is
Fiber twist pitch _P F · · · · · · · of the pitch _{P UV>} optical fiber UV fixing material (Equation 1)
And
The length L _UV of the UV fixing material is
Length of UV fixing material L _UV ≦ Fiber twist pitch of optical fiber P _F / 2 (Equation 2)
Need to be.

  As described above, when both the conditions of (Expression 1) and (Expression 2) are satisfied, in addition to the wavelength of 1.55 μm normally used in the transmission line, 1.625 μm used mainly for long-distance transmission. Good temperature characteristics were exhibited even at a wavelength of.

  Next, the three conditions (1) to (3) described above will be described in more detail based on the data in Table 1. As a criterion for determination, it is acceptable that the loss temperature fluctuation characteristic is 0.3 dB / km or less.

  Data numbers 1 to 19 are attached to the data in Table 1, and as shown in FIG. 5, the data corresponding to the above three conditions (1) to (3) are indicated by hatching, and it corresponds to it. The data not to be displayed was classified by stippling. Furthermore, the average value, the maximum value, and the minimum value of the data for each classification are shown in the graphs of FIGS. 6 to 9 are data of loss temperature fluctuation characteristics at a wavelength of 1.55 μm, and FIGS. 10 to 13 are data of loss temperature fluctuation characteristics at a wavelength of 1.625 μm, and other data are omitted. is doing.

  FIG. 6 is a graph showing loss temperature fluctuation characteristics data at a wavelength of 1.55 μm for the test cable corresponding to the condition of (Equation 1) in Table 1. That is, in Table 1, the average value, the maximum value, and the minimum value of the data at 1.55 μm marked with ○ in the (Equation 1) pass column are illustrated.

  As can be seen from this graph, the average value, the maximum value, and the minimum value of the loss temperature fluctuation characteristics are 0.3 dB / km or less at any of the initial characteristics, low temperature (−30 ° C.), and high temperature (+ 70 ° C.). is there. Therefore, the optical fiber cable 1 that satisfies the condition of (Equation 1) can obtain good transmission characteristics.

  FIG. 7 is a graph showing data of loss temperature fluctuation characteristics at 1.55 μm for a test cable not corresponding to the condition of (Equation 1) in Table 1. That is, in Table 1, the average value, the maximum value, and the minimum value of the data marked with “x” are shown in the column of (Equation 1) pass.

  As can be seen from this graph, the average value and the maximum value of the loss temperature fluctuation characteristics at low temperatures (−30 ° C.) exceed 0.3 dB / km.

  FIG. 8 is a graph showing loss temperature fluctuation characteristics data at a wavelength of 1.55 μm for the test cable corresponding to the condition of (Equation 2) in Table 1. That is, in Table 1, the average value, the maximum value, and the minimum value of the data marked with “◯” are shown in the (Equation 2) pass column.

  As can be seen from this graph, the average value, the maximum value, and the minimum value of the loss temperature fluctuation characteristics are 0.3 dB / km or less at any of the initial characteristics, low temperature (−30 ° C.), and high temperature (+ 70 ° C.). is there. Therefore, the optical fiber cable 1 that satisfies the condition of (Equation 2) can obtain good transmission characteristics.

  FIG. 9 is a graph showing data of loss temperature fluctuation characteristics at 1.55 μm for a test cable not satisfying the condition of (Equation 2) in Table 1. That is, in Table 1, the average value, the maximum value, and the minimum value of the data marked with “x” are shown in the (Equation 2) pass column.

  As can be seen from this graph, the average value and the maximum value of the loss temperature fluctuation characteristics at low temperatures (−30 ° C.) exceed 0.3 dB / km.

  FIG. 10 is a graph showing loss temperature fluctuation characteristics data at a wavelength of 1.625 μm for the test cable corresponding to both the conditions (Equation 1) and (Equation 2) in Table 1. That is, in Table 1, the average value, the maximum value, and the minimum value of the data marked with ○ are shown in the (Equation 1) pass column and (Equation 2) pass column.

  As can be seen from this graph, the average value, the maximum value, and the minimum value of the loss temperature fluctuation characteristics are 0.3 dB / km or less at any of the initial characteristics, low temperature (−30 ° C.), and high temperature (+ 70 ° C.). is there. Therefore, the optical fiber cable 1 that satisfies both the conditions of (Expression 1) and (Expression 2) can obtain good transmission characteristics even at a wavelength of 1.625 μm in addition to a wavelength of 1.55 μm.

  FIG. 11 is a graph showing loss temperature fluctuation characteristics data at 1.625 μm for a test cable not satisfying the condition of (Equation 1) in Table 1. That is, in Table 1, the average value, the maximum value, and the minimum value of the data indicated by x are shown in the column of (Equation 1) pass.

  As can be seen from this graph, the maximum value of the loss temperature fluctuation characteristic exceeds 0.3 dB / km, and the average value, minimum value, and maximum value of the loss temperature fluctuation characteristic at a low temperature (−30 ° C.) are the initial characteristics. The average value and the maximum value of the loss temperature fluctuation characteristics at high temperature (+ 70 ° C.) exceed 0.3 dB / km.

  FIG. 12 is a graph showing loss temperature fluctuation characteristics data at a wavelength of 1.625 μm with a test cable not satisfying the condition of (Equation 2) in Table 1. That is, in Table 1, the average value, the maximum value, and the minimum value of the data marked with “x” are shown in the (Equation 2) pass column.

  As can be seen from this graph, the initial characteristic has an average value and a maximum value of the loss temperature fluctuation characteristic exceeding 0.3 dB / km, and an average value and a minimum value of the loss temperature fluctuation characteristic at a low temperature (−30 ° C.), The maximum value exceeds 0.3 dB / km, and the average value and the maximum value of the loss temperature fluctuation characteristics at high temperature (+ 70 ° C.) exceed 0.3 dB / km.

  FIG. 13 is a graph showing loss temperature fluctuation characteristics data at a wavelength of 1.625 μm in a test cable that does not satisfy both the conditions of (Equation 1) and (Equation 2) in Table 1. That is, in Table 1, the average value, the maximum value, and the minimum value of the data marked by X are shown in both the (Formula 1) pass column and the (Formula 2) pass column.

  As can be seen from this graph, the average value and the maximum value of the loss temperature fluctuation characteristics exceed 0.3 dB / km, and both the low temperature (−30 ° C.) and the high temperature (+ 70 ° C.) The average value, minimum value, and maximum value of the loss temperature fluctuation characteristics exceed 0.3 dB / km.

  In addition, although one of (Equation 1) and (Equation 2) passes (circle), the case where the other fails (×) is not shown in the graph, this point For example, in data numbers 6, 14, 16, and 17 in which (Equation 1) is acceptable (circle) and (Equation 2) is unacceptable (x), the wavelength is 1.55 μm. Loss temperature fluctuation characteristics are good at 0.3 dB / km or less at all locations, but the loss temperature fluctuation characteristics at a wavelength of 1.625 μm are poor with some locations exceeding 0.3 dB / km. .

  On the other hand, the loss temperature at a wavelength of 1.55 μm is obtained for data numbers 2, 7, 8, 10, and 18 in which (Equation 2) is acceptable (circle) and (Equation 1) is not acceptable (x). The fluctuation characteristics are good at 0.3 dB / km or less at all locations, but the loss temperature fluctuation characteristics at a wavelength of 1.625 μm are poor because there are places where the frequency exceeds 0.3 dB / km.

  Therefore, when either one of (Formula 1) and (Formula 2) passes (circle mark), it turns out that the loss temperature fluctuation characteristic in the wavelength of 1.55 micrometer is favorable.

  In the embodiment described above, the optical fiber 3 has been described with the twisting direction of the optical fiber 3 as an example, but the present invention can be applied even in the SZ direction.

  In the above-described embodiment, the slot type optical fiber cable 1 having a C-shaped single groove has been described as an example. However, the effects of the three conditions (1) to (3) described above are the same as those of the C-type. Similar to the slot type optical fiber cable having one groove, the slot type optical fiber cable having one U-shaped groove and the center tube type optical fiber cable have the same effect.

  Further, in the above-described embodiment, the example in which the intermittent fixing material using the UV resin 17 is used has been described. However, as another example, an adhesive resin such as a hot melt resin is used as the intermittent fixing material, and The relationship between the adhesive fixing material pitch (adhesive resin coating pitch), the adhesive fixing material length (adhesive resin coating dimension), and the fiber twist pitch (optical fiber 3 twist pitch) affects the loss temperature fluctuation characteristics. Regarding the influence, when an optical fiber cable was prototyped and analyzed, it was basically the same as the case of the intermittent fixing material of the UV resin 17 described above.

  That is, in this case, the following three conditions (1) to (3) are conditions for obtaining good transmission characteristics.

(1) The relationship between the pitch of the adhesive fixing material (adhesive fixing material pitch) and the twist pitch (fiber twist pitch) of the one or more optical fibers is:
The pitch of the adhesive fixing material> the fiber twist pitch of the optical fiber.

(2) The relationship between the length of each adhesive fixing material (adhesive fixing material length) and the twist pitch (fiber twist pitch) of the optical fiber of the one or more optical fibers is:
The length of the adhesive fixing material ≦ the fiber twist pitch of the optical fiber / 2.

(3) The relationship between the pitch of the adhesive fixing material (adhesive fixing material pitch) and the twist pitch (fiber twist pitch) of the plurality of optical fibers is as follows:
Pitch of adhesive fixing material> Fiber twist pitch of optical fiber ...
The relationship between the length of the adhesive fixing material (adhesive fixing material length) and the twist pitch (fiber twist pitch) of the one or more optical fibers is:
The length of the adhesive fixing material ≦ the fiber twist pitch of the optical fiber / 2.

  Since the operation and effect are substantially the same as those of the intermittent fixing material of the UV resin 17 described above, a detailed description thereof will be omitted.

1 Optical fiber cable (in this embodiment)
3 Optical fiber 5 Groove 7 Slot rod 9 Strength member (tension member)
11 Opening 13 Vertically attached tape 15 Uneven thickness sheath 17 UV curable resin (UV resin)
19 UV fixing material (intermittent fixing material)
21 Stranding Machine 23 Rotating Shaft 25 Rotating Body 27 Optical Fiber Reel 29 Concentration Die 31 Fiber Gathering Unit 33 UV Resin Filling Device 35 UV Lamp 37 Ultraviolet Light 39 Guide Roller 41 Vertical Tape Gathering Unit 43 Vertical Tape Reversing Unit 45 Extruder 47 Extrusion head

Claims (6)

A one-groove slot rod having one groove in which one or more optical fibers are twisted and housed inside, a longitudinally attached tape covering the opening of the slot of the slot rod, the longitudinally attached tape, In an optical fiber cable comprising a sheath covering the periphery of a slot rod,
In order to intermittently fix one or more optical fibers in the slot of the slot rod, UV curable resin is intermittently fixed in advance in the longitudinal direction to the longitudinal tape, and a UV fixing material is provided.
The relationship between the pitch of the UV fixing material and the twist pitch of the one or more optical fibers is as follows:
An optical fiber cable characterized in that the pitch of the UV fixing material> the fiber twist pitch of the optical fiber. A one-groove slot rod having one groove in which one or more optical fibers are twisted and housed inside, a longitudinally attached tape covering the opening of the slot of the slot rod, the longitudinally attached tape, In an optical fiber cable comprising a sheath covering the periphery of a slot rod,
In order to intermittently fix one or more optical fibers in the slot of the slot rod, UV curable resin is intermittently fixed in advance in the longitudinal direction to the longitudinal tape, and a UV fixing material is provided.
The relationship between the length of the UV fixing material and the twist pitch of the one or more optical fibers is:
Length of UV fixing material ≦ fiber twist pitch of optical fiber / 2
An optical fiber cable characterized by A one-groove slot rod having one groove in which one or more optical fibers are twisted and housed inside, a longitudinally attached tape covering the opening of the slot of the slot rod, the longitudinally attached tape, In an optical fiber cable comprising a sheath covering the periphery of a slot rod,
In order to intermittently fix one or more optical fibers in the slot of the slot rod, UV curable resin is intermittently fixed in advance in the longitudinal direction to the longitudinal tape, and a UV fixing material is provided.
The relationship between the pitch of the UV fixing material and the twist pitch of the one or more optical fibers is as follows:
The pitch of the UV fixing material> the fiber twist pitch of the optical fiber, and the relationship between the length of the UV fixing material and the twist pitch of the one or more optical fibers is
Length of UV fixing material ≦ fiber twist pitch of optical fiber / 2
An optical fiber cable characterized by A one-groove slot rod having one groove in which one or more optical fibers are twisted and housed inside, a longitudinally attached tape covering the opening of the slot of the slot rod, the longitudinally attached tape, In an optical fiber cable comprising a sheath covering the periphery of a slot rod,
In order to intermittently fix one or more optical fibers in the slot of the slot rod, an adhesive resin is intermittently fixed in advance in the longitudinal direction to the longitudinal tape, and an adhesive fixing material is provided.
The relationship between the pitch of the adhesive fixing material and the twist pitch of the one or more optical fibers is as follows:
Pitch of adhesive fixing material> Fiber twist pitch of optical fiber / 2
An optical fiber cable characterized by One slot slot rod having one groove in which one or more optical fibers are twisted and housed inside, a longitudinal tape attached vertically to cover the opening of the slot of the slot rod, the longitudinal tape, In an optical fiber cable comprising a sheath covering the periphery of a slot rod,
In order to intermittently fix the plurality of optical fibers in the slot of the slot rod, the adhesive tape is intermittently fixed in advance in the longitudinal direction of the longitudinal tape, and an adhesive fixing material is provided.
The relationship between the length of the adhesive fixing material and the twist pitch of the one or more optical fibers is as follows:
Length of adhesive fixing material ≦ Fiber twist pitch of optical fiber / 2
An optical fiber cable characterized by A one-groove slot rod having one groove in which one or more optical fibers are twisted and housed inside, a longitudinally attached tape covering the opening of the slot of the slot rod, the longitudinally attached tape, In an optical fiber cable comprising a sheath covering the periphery of a slot rod,
In order to intermittently fix the plurality of optical fibers in the slot of the slot rod, the adhesive tape is intermittently fixed in advance in the longitudinal direction of the longitudinal tape, and an adhesive fixing material is provided.
The relationship between the pitch of the adhesive fixing material and the twist pitch of the one or more optical fibers is as follows:
The relationship between the pitch of the adhesive fixing material> the fiber twist pitch of the optical fiber, and the length of each adhesive fixing material and the twist pitch of the one or more optical fibers,
Length of adhesive fixing material ≦ Fiber twist pitch of optical fiber / 2
An optical fiber cable characterized by

Images