JP4243273B2 - Optical fiber sheet - Google Patents

Description

  The present invention relates to an optical fiber sheet, and more particularly to an optical fiber sheet in which an optical fiber is wound in a ring shape and fixed to a substrate.

  In general, in a fiber type dispersion compensator, an optical fiber amplifier, and the like, a long optical fiber is often used as an element. In such a case, it is preferable to wind the optical fiber on a reel or the like in order to save the space of the apparatus and suppress the deterioration of the optical fiber characteristics.

  However, even when the optical fiber is wound around a reel or the like and accommodated in the apparatus, the optical fiber may receive a side pressure from the bottom of the reel or may be subjected to internal stress due to local bending. As a result, the optical fiber is deformed, resulting in deterioration of optical fiber characteristics such as a large transmission loss. Therefore, a device for reducing the side pressure and internal stress and accommodating the optical fiber in the apparatus has been proposed.

  For example, Patent Document 1 discloses an optical fiber coil. In this method of manufacturing an optical fiber coil, first, an optical fiber is wound around a reel body, and then the wound optical fiber is bonded and fixed to a reel flange, and then the reel body is removed. .

  Patent Document 2 discloses an optical fiber coil. In this optical fiber coil, a dummy optical fiber is wound around the bottom of the reel.

  Patent Document 3 discloses an optical fiber holder. In this optical fiber holder, an optical fiber wound in an annular shape is disposed on a base material, and the lower surface of the optical fiber and the base material are bonded and fixed, and the covering member is sandwiched between the optical fibers. It is put on the base material. In addition, an adhesive such as UV curable resin is applied to a part of the circumferential direction of the optical fiber wound in an annular shape, so that the contact portions of the optical fiber wound in an annular shape are bonded and fixed to each other. ing.

Patent Document 4 discloses an optical fiber sheet. In this optical fiber sheet, an optical fiber bundled in a coil shape is heat-sealed to two resin films and sealed.
JP 2000-275446 A JP 2001-213573 A JP 2003-287627 A JP 2003-344670 A

  As described above, when the contact portions of the optical fibers wound in a ring shape are bonded and fixed, the winding of the optical fiber wound in a ring shape can be prevented from being unwound. However, since an external force such as a binding force is applied to the portion of the optical fiber that is bonded and fixed, the optical fiber is deformed, resulting in a large light transmission loss. That is, if the contact portions of the optical fibers wound in a ring shape are bonded and fixed using an adhesive, there is a risk of deteriorating the optical fiber characteristics.

  On the other hand, if the portions of the optical fibers wound in a ring shape are fixed to the substrate without bonding and fixing, the optical fibers may be unwound over time. If the winding of the optical fiber is unwound, the unwound optical fiber may come into contact with other parts in the apparatus, leading to deformation of the optical fiber, damage to other parts, and the like.

  This invention is made | formed in view of this point, The place made into the objective is providing the optical fiber sheet which can bundle an optical fiber, without causing deterioration of an optical fiber characteristic.

  The optical fiber sheet of the present invention is an optical fiber sheet in which an optical fiber is wound in a ring shape and fixed to a substrate. Specifically, the optical fibers wound in a ring shape are bundled with a binding material. And, a part of the binding material is in contact with and bonded to the other part of the binding material, and at the place where the binding material and the optical fiber wound in the ring shape are in contact with each other, both are not bonded. .

  In such a configuration, the binding material binds the optical fiber without being bonded to the optical fiber wound in a ring shape. Therefore, it is possible to prevent the binding force or the like from being applied to the optical fiber wound in a ring shape. Therefore, deformation to the optical fiber can be prevented, and as a result, deterioration of the optical fiber characteristics can be prevented.

  Here, “non-adhesive” means a state in which the binding material and the optical fiber wound in a ring shape are in contact with each other without using an adhesive, and the binding material itself does not pass through the adhesive. It is not included when it has an adhesive force to the optical fiber.

  In the optical fiber sheet of the present invention, the binding material is preferably a tape having adhesiveness between the tapes and substantially free of adhesiveness with the optical fiber, more preferably a tape having self-bonding property. Tetrafluoroethylene tape.

  Here, the “tape having self-bonding property” means a tape that, when the tapes are left in contact with each other, the contact portions are deformed and bonded with the passage of time.

  In the optical fiber sheet of the present invention, a covering material is bonded and fixed to the substrate, and the covering material is preferably covered with an optical fiber wound in a ring shape between the substrate and the substrate. . With such a configuration, the optical fiber bundle can be more reliably prevented from separating from the substrate, so that the optical fiber sheet can be used stably.

  According to the present invention, optical fibers can be bundled without causing deterioration of optical fiber characteristics.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The present invention is not limited to the following embodiment.

  In this embodiment, the structure and manufacturing method of the optical fiber sheet 10 are shown using FIG.1 and FIG.2. FIG. 1 is a perspective view showing an optical fiber sheet 10, and FIG. 2 is a cross-sectional view taken along the line II-II shown in FIG. Note that “upper” means “upper” in each drawing.

  The optical fiber sheet 10 is accommodated in a fiber-type dispersion compensator, an optical fiber amplifier (both not shown) or the like, and a long optical fiber 17 is wound in a ring shape and fixed to the substrate 11. As shown in FIG. 1, the optical fiber sheet 10 includes a substrate 11, an optical fiber wound in a ring shape (hereinafter referred to as “optical fiber bundle”) 15, binding materials 19, 19,. I have. The adhesive 13 is applied to the entire upper surface 11 a of the substrate 11, and the optical fiber bundle 15 and the covering material 21 are fixed to the upper surface 11 a of the substrate 11 via the adhesive 13. Further, the binding materials 19, 19,... Are wound around the optical fiber bundle 15.

  The substrate 11 is made of PET (polyethylene terephthalate), is a plate having a substantially square planar shape, and has at least an upper surface 11a formed in a planar sheet shape.

  The optical fiber bundle 15 is bonded and fixed to the upper surface 11a so that the center axis of the ring is substantially perpendicular to the upper surface 11a, and a long optical fiber 17 is wound in a ring shape. The outer shape is cylindrical as shown in FIG. Thus, by accommodating the long optical fiber 17 as the optical fiber bundle 15 in a fiber type dispersion compensator, an optical fiber amplifier, or the like, it is possible to reduce the size of the fiber type dispersion compensator, the optical fiber amplifier, or the like. .

  The inner diameter of the ring of the optical fiber bundle 15 is preferably equal to or larger than the allowable bending diameter of the optical fiber 17 and is, for example, 60 mm or larger. Thereby, the deterioration of the optical fiber characteristics due to bending can be prevented. The optical fiber 17 used is, for example, 1.3 μm SMF (Single Mode Fiber), EDF (Erbium Doped Fiber), DCF (Dispersion Compensating Fiber), or 1.55 μm DSF (Dispersion Shifted Fiber). The total length is generally about 10 to 20 km.

  Each binding material 19 is a tape having self-bonding properties, for example, a polytetrafluoroethylene tape (tape width is 13 mm). Here, the self-bonding tape in the present embodiment means that when the tapes are left in contact with each other and left to stand, the contact portion is deformed and bonded over time, while there is no adhesive force to the outer surface of the optical fiber 17. It means tape or very small tape. Moreover, the tape whose adhesive force with respect to the outer surface of the optical fiber 17 is very small means a tape whose adhesive force is 0.5 N / cm or less, for example.

  The binding members 19, 19,... Are wound around the optical fiber bundle 15 so as to bundle the wound optical fibers 17 at positions where the ring of the optical fiber bundle 15 is equally divided into four in the circumferential direction. In other words, each binding material 19 is wound substantially perpendicularly to the winding direction of the optical fiber 17 in the optical fiber bundle 15.

  The winding method of each binding material 19 will be described in detail. Each binding material 19 is wound around the optical fiber bundle 15 so that both ends thereof are in contact with each other, and thereby the optical fiber bundle 15 can be bound. it can. On the other hand, each binding material 19 is wound around the optical fiber bundle 15 without being bonded to the optical fiber 17. For this reason, it is possible to prevent an external force such as a binding force from being applied to the optical fiber 17 at a portion bound by each binding material 19, thereby preventing the optical fiber 17 from being deformed. Thereby, deterioration of the optical fiber characteristics can be prevented. As mentioned above, if the optical fiber bundle 15 is bundled using each binding material 19, the optical fiber bundle 15 can be bundled without deteriorating the optical fiber characteristics.

  The covering material 21 is, for example, a sheet made of heat flexible resin (polyethylene (PE) or the like) having a thickness of 100 μm, and is adhered and fixed to the upper surface 11 a of the substrate 11 and is covered with the optical fiber bundle 15.

  Next, the manufacturing method of the optical fiber sheet 10 is shown.

  First, an optical fiber bundle 15 is formed using an optical fiber winding device (not shown). Specifically, first, the long optical fiber 17 is spirally wound around the outer surface of the bobbin body, and the optical fiber 17 is wound around the entire outer surface of the bobbin body. An optical fiber 17 is spirally wound on the optical fiber. Thus, the optical fiber bundle 15 having a substantially cylindrical shape can be formed by winding the optical fiber 17 in a ring shape.

  Next, the binding materials 19, 19,... Are wound around the optical fiber bundle 15. Specifically, each binding material 19 is wound so that the wound optical fibers 17 are bundled, and both ends of each binding material 19 are brought into contact with each other. In addition, it is preferable to wind the binding materials 19, 19,. Thereafter, the optical fiber bundle 15 is removed from the bobbin.

  Subsequently, a substrate in which the adhesive 13 is applied to the upper surface 11a of the substrate 11 is prepared. Then, the center axis of the ring of the optical fiber bundle 15 is disposed substantially perpendicular to the upper surface 11a of the substrate 11, and one end 15a of the optical fiber bundle 15 is bonded and fixed to the upper surface 11a.

  Then, the covering material 21 is placed on the upper surface 11 a of the substrate 11. Specifically, the coating material 21 that has been softened by heating is covered from above the optical fiber bundle 15 while evacuating. Thereby, the optical fiber sheet 10 is completed.

  Below, the effect which the optical fiber sheet 10 of this embodiment shows is shown.

  In the optical fiber sheet 10 of this embodiment, the binding materials 19, 19,... Are wound around the optical fiber bundle 15. Since each binding material 19 is wound around the optical fiber bundle 15 at both ends thereof, the optical fiber bundle 15 can be bundled. Each binding material 19 is wound around the optical fiber bundle 15 without being bonded to the optical fiber 17. For this reason, it is possible to prevent an external force such as a binding force from being applied to the optical fiber 17 even at a location where the binding material 19 is bound, and thus deformation of the optical fiber 17 can be prevented. As described above, each binding material 19 can bind the optical fibers 17 without deformation of the optical fibers 17, so that the optical fiber bundles 15 can be bound without causing deterioration of the optical fiber characteristics.

  The binding material is not limited to a polytetrafluoroethylene tape as long as it has the above self-bonding property. For example, a butyl rubber tape may be used, and an ethylene propylene rubber (EPM) may be used. EPDM) tape. Moreover, the location around which the binding material is wound and the number of binding materials are not limited to the above description.

  The type of optical fiber is not limited to the above description. For example, a dummy fiber for a measuring instrument, an SMF for a line test, an EDF for a fiber amplifier, a DCF for a fiber dispersion compensator, and a rotational speed are measured. An optical fiber gyro used as a sensor may be used.

  Moreover, when attaching an optical fiber sheet to an apparatus or the like, the optical fiber bundle may be attached with the optical fiber bundle up, as shown in FIG.

In this example, the strain characteristics of the optical fiber in the optical fiber sheet of the above embodiment and the strain characteristics of the optical fiber wound around the coil were examined.
<Measurement method of strain characteristics>
First, the optical fiber sheet of the above embodiment and the one obtained by winding an optical fiber around a coil were prepared. Here, the optical fiber of the optical fiber sheet was SMF having a total length of 200 m, and the inner diameter of the optical fiber bundle of the optical fiber sheet was 60 mm. The optical fiber wound around the coil was an SMF having a total length of 200 m, and the outer diameter of the coil was 350 mm.

  Next, the strain in the longitudinal direction of the optical fiber of the optical fiber wound around the optical fiber sheet and the coil was measured using an optical fiber strain measuring device (BOTDR, AQ8603 type, manufactured by Yokogawa Electric Corporation).

In this embodiment, the strain in the longitudinal direction of the optical fiber is defined as the ratio of the stress applied to the optical fiber to the Young's modulus of the glass, and the strain of the straight optical fiber not subjected to the stress is 0%. It is.
<Measurement results>
The strain characteristic of the optical fiber wound around the bobbin was 0.13%. This is considered to be a distortion characteristic derived from the pulling bending stress when the optical fiber is wound around the bobbin.

  On the other hand, the strain characteristic of the optical fiber of the optical fiber sheet was 0.003% to 0.005%. From the above, the distortion characteristics of the optical fiber are improved by about two digits when the optical fiber is fixed to the optical fiber sheet as in this embodiment, compared to the case where the optical fiber is wound around the bobbin.

  As described above, the present invention is useful for optical fiber sheets, and is effective when bundling long optical fibers without degrading optical fiber characteristics.

It is a perspective view of an optical fiber sheet. It is sectional drawing of an optical fiber sheet.

Explanation of symbols

10 optical fiber sheet 11 substrate 15 optical fiber bundle (optical fiber wound in a ring shape)
17 Optical fiber 19 Bundling material 21 Coating material

Claims (4)

An optical fiber sheet in which an optical fiber is wound in a ring shape and fixed to a substrate,
The optical fiber wound in a ring shape is bundled by a binding material,
Part of the binding material is in contact with and bonded to the other part of the binding material,
An optical fiber sheet in which the binding material and the optical fiber wound in the ring shape are in non-adhesion at a portion where the binding material and the optical fiber wound in the ring shape are in contact with each other. The optical fiber sheet according to claim 1,
The binding material is an optical fiber sheet which is a self-bonding tape. In the optical fiber sheet according to claim 1 or 2,
The binding material is an optical fiber sheet which is a tape made of polytetrafluoroethylene. In the optical fiber sheet according to any one of claims 1 to 3,
A covering material is fixed to the substrate,
The said coating | covering material is an optical fiber sheet covered with the optical fiber wound by the said ring shape pinched | interposed between the said board | substrates.

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