JPH01138518A - Tape-shaped optical fiber core - Google Patents

Abstract

PURPOSE:To enable the easy tearing of a covering layer so that a tape-shaped optical fiber can be branched to plural optical fibers by connecting the covering layers in a part to be branched by a small connecting material having a low elongation rate. CONSTITUTION:The tape-shaped optical fiber is constituted of 4 pieces of the optical fibers. Coating layers 2a, 2b of the fibers on one side and the coating layers 2c, 2d of the fibers on the other wise are in contact with each other. Four pieces of the optical fibers constitute respectively two pieces of the optical fibers which are integrated to each other by the covering layers 3a, 3b. The connecting material 4 which integrates these fibers is formed of a thermosetting resin or UV curing resin and has the smaller elongation rate than the elongation rate of the covering layer 3. The tape-shaped optical fiber is thus branched to the plural optical fibers by easily tearing the covering layer.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a tape-shaped optical fiber core.

[Prior art and its problems]

BACKGROUND ART Conventionally, a tape-shaped optical fiber core wire is known in which a plurality of optical fiber strands are arranged in parallel and a coating layer is provided all at once to form a single optical fiber core wire. FIG. 3 is a perspective view of a conventional example. As shown in the figure, the optical fiber consists of a glass fiber 1 consisting of a core and a cladding, and a coating layer 2 coated on the outside thereof. Here, the coating layer 2 is made of silicone resin, for example,
It forms a buffer layer that prevents mechanical impact from being applied to the glass fiber 1. The four optical fiber strands thus constructed are arranged in parallel on a plane and are integrated by a coating layer 3 made of resin or the like as shown in FIG.

Incidentally, in recent years, the introduction of subscriber optical fiber cables has been progressing, but for this purpose it becomes necessary to branch out multi-core optical fibers.

However, it is not easy to branch a tape-shaped optical fiber into a plurality of cores. Specifically, for example, the third
As shown by the dotted line A in Figure (a), it is not easy to cut a tape-shaped optical fiber core lengthwise into two core wires, and when it is actually cut, the stress caused by the process causes the glass to become thinner. The transmission characteristics of the fiber I often deteriorated.

On the other hand, as shown in FIG. 3(b), after removing the coating layer 3 together with the coating layer 2 to expose the glass fiber 1, the glass fiber 1 is connected to an optical connector (not shown) or other Another method is to connect to optical fiber. However, this method requires a step of removing the coating layer 2 and the covering layer 3, and also requires highly accurate alignment, which makes branching work extremely difficult.

Therefore, an object of the present invention is to provide a tape-shaped optical fiber core i that can be easily branched into a plurality of optical fiber cores without deteriorating the transmission characteristics of the destination fiber.

[Means for solving problems]

The tape-shaped optical fiber core wire according to the present invention is a tape-shaped optical fiber core wire in which a plurality of optical fiber wires are arranged in parallel on a predetermined plane and covered with a coating layer. A coating layer is separate between at least one optical fiber and another optical fiber adjacent to one side of the optical fiber, and these are a connecting material between the separate coating layers. The elongation rate of this connecting material is smaller than the elongation rate of the covering layer.

[Effect]

According to the tape-shaped optical fiber core wire of the present invention, the coating layer is separate at the part to be branched, and these are integrated by a connecting material with a lower elongation rate than the coating layer, so it is easy to It can be cut into multiple optical fibers.

〔Example〕

Hereinafter, the present invention will be described in detail with reference to FIGS. 1 and 2 of the accompanying drawings. In addition, in the description of the drawings, the same elements are given the same reference numerals, and redundant description will be omitted.

FIG. 1 is a perspective view of a tape-shaped optical fiber core according to an embodiment. As shown in the figure, this tape-shaped optical fiber core has 4
The coating layer 2a of the strands on one side is composed of optical fiber strands.

2b and a coating layer 2c of the strands on the other side.

2d are in contact with each other. The coating layers 2b and 2c of the two intermediate optical fiber strands adjacent to each other are separated by a constant interval. Therefore, each of the four optical fibers constitutes two optical fiber cores,
These are the coating layers 3a made of, for example, urethane acrylate resin.

3b. A connecting member 4 for integrating these core wires is formed with a constriction at this interval portion (branch portion).

Here, the connecting member 4 is formed of a thermosetting resin or an ultraviolet curable resin, and has a lower elongation rate (ultimate elongation rate) than the coating layer 3.

According to this tape-shaped coated optical fiber, branching into two coated optical fibers can be easily performed.

That is, since the physical strength is reduced at the connecting member 4 (it breaks quickly when stress is applied), the glass fiber la is cut at this point.

One optical fiber core containing 1b and glass fiber l
It can be easily branched to the other optical fiber core including c and ld. At this time, since each of the optical fiber strands is covered with coating layers 3a and 3b having a high elongation rate, the strands are not exposed after branching.

FIG. 2 is a sectional view showing a modification of the above embodiment. In the tape-shaped optical fiber coated wire of FIG. Although the covering layers 3 are separate from each other, they are in contact with each other, and a connecting material 4 with a small elongation rate is provided between them. Therefore, since the physical strength of this part is reduced, if stress is applied, the connecting member 4 will break first, and it can easily branch into two core wires.

In the tape-shaped optical fiber core shown in FIG.
The coating layers 3 are separate from each other among the three optical fiber cores including the real glass fiber 1, and these are integrated by a connecting material 4 having a small elongation rate. Therefore,
By applying stress to break and tear the connecting member 4, it is possible to branch into two core wires.

In addition, in the tape-shaped optical fiber coated wire shown in FIG. There is. Although these are integrated by a connecting member 4, they are not constricted.

However, since the connecting member 4 is made of a material with a low elongation rate, its physical strength is low and it is easily torn, so that it can easily branch into two core wires.

Thus, in the present invention, it is not an essential requirement that the branch portion be constricted.

Furthermore, in the tape-shaped optical fiber coated wire shown in FIG. 2(d), the coating layers 3 are separate and in contact with each other between the two optical fiber coated wires each including two glass fibers 1. These are integrated by a connecting member 4 that covers the entire body. Even in this case, since the elongation rate of the connecting member 4 is small, branching into two optical fibers can be easily performed.

The present invention is not limited to what has been described above, and various modifications are possible.

For example, the covering material and the connecting material are not limited to UV resins, but may also be thermosetting resins, in which case they will be cured using a heater or an electron beam.

As the UV resin, for example, a urethane acrylate-based UV curing resin can be used, and the elongation rate can be appropriately set by selecting the type and amount of the additive. Therefore,
For example, the same resin may be used as the covering material and the connecting material, and an additive that reduces the elongation rate may be added only to the connecting material. Furthermore, one or more wire rods may be embedded in the connecting member 4 in the longitudinal direction. In this way, by pulling the wire rod in a direction perpendicular to the longitudinal direction, the connecting member can be preliminarily cut to facilitate branching.

〔Effect of the invention〕

As explained above in detail, according to the tape-shaped optical fiber core wire of the present invention, the coating layer is connected by a connecting material with a small elongation rate at the part where it should be branched, so it can be easily cut here and divided into multiple pieces. It can be an optical fiber core. Therefore, it is possible to branch into a plurality of coated optical fibers without deteriorating the transmission characteristics of the optical fiber or exposing the bare optical fiber.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a ribbon-shaped optical fiber according to an embodiment of the present invention, FIG. 2 is a sectional view of a modified example thereof, and FIG. 3 is a perspective view of a tape-shaped optical fiber according to a conventional example. be. 1.1a-1d...Glass fiber, 2.2a-2d
... Coating layer, 3... Covering layer, 4... Connecting material. Patent applicant: Sumitomo Electric Industries, Ltd. Representative patent attorney Yoshiki Hase Figure 1 Figure 2 Conventional example Figure 3

Claims (1)

[Scope of Claim] A tape-shaped coated optical fiber in which a plurality of optical fiber strands are arranged in parallel on a predetermined plane and covered with a coating layer, comprising: at least one of the plurality of optical fiber strands;
The coating layer is separate from another optical fiber adjacent to one side of this optical fiber, and these are integrated by a connecting material between the separate coating layers. 1. A tape-shaped optical fiber core wire, characterized in that the elongation rate of the connecting material is smaller than the elongation rate of the coating layer.