JPH0886920A - Holding structure for optical fiber - Google Patents

Abstract

PURPOSE: To integrally handle a long-length optical fiber without loosening and to maintain the fiber without producing microbending or the like by sealing the optical fiber with a soft resin into a sheet state and holding it. CONSTITUTION: A long optical fiber 1 is circulated into an annular state and its circulating position is dislocated from each other on a plane so as not to stack the fiber to give a volume in the width direction. This optical fiber 1 is sealed with a soft resin 2 in a sheet state and held. As for the soft resin 2, for example, silicon-based resin is used, or a urethane rubber, UV resin, and epoxy resin can be used. The optical fiber 1 may be circulated like a '8' shape, spiral or drum while the circulating position is dislocated on a plane and then sealed with a soft resin 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for holding a long optical fiber.

[0002]

2. Description of the Related Art Generally, in a device such as an optical fiber amplifier or an optical fiber gyroscope, a long optical fiber is used as its element.

For example, an optical fiber amplifier is provided with an amplification optical fiber doped with a rare earth element such as Er in the core of the optical fiber. The optical amplification factor of this amplification optical fiber is the concentration of the element to be doped and the optical density. It depends on the so-called concentration length product, which is the product of the fiber length.

Therefore, in order to obtain a large amplification factor,
Although it is only necessary to set the concentration product to a large value, in that case, if the concentration of the element to be doped is excessively high, disadvantages such as vitrification are hindered. The length is set to be somewhat longer.

As described above, when assembling a device using a long optical fiber, it is necessary to store the optical fibers as a group in the device.

Therefore, conventionally, as shown in FIG.
Processing such as winding a long optical fiber a around a reel b, or drawing and mounting the optical fiber in the apparatus is performed.

[0007]

However, the reel is
In the case of using b, conventionally, in order to perform the aligned winding, the optical fiber a is continuously wound around the reel b in a state of being tensioned.
In a portion where a is overlapped with each other, a local slight bending, so-called microbending, occurs, which causes a problem such as an increase in loss of the optical fiber a.

Further, when the optical fiber is routed inside the apparatus, the optical fiber is hooked on the hook portion or the like at a predetermined pitch while maintaining an appropriate curvature so as to prevent the bending loss from increasing or coming apart. It has to be done and it takes time to store.

The present invention has been made in order to solve the above-mentioned problems, and it is possible to handle a long optical fiber as a whole without the entire optical fiber being dislocated, and it is troublesome to arrange the optical fiber in the apparatus. Therefore, an object is to enable stable holding without causing microbending or the like.

[0010]

The present invention adopts the following constitution in order to solve the above problems.

That is, in the optical fiber holding structure according to the first aspect of the present invention, the optical fibers are arranged such that their circling positions are displaced from each other in a plane.
The sheet is sealed and held by a soft resin.

In the optical fiber holding structure of the present invention according to the second aspect, the optical fibers are held by being sealed with a soft resin in a state of being bundle-wound in an annular shape.

[0013]

In either of the first and second aspects of the invention, since the optical fiber is sealed with the soft resin,
The whole can be handled as one without being disassembled and can be easily arranged in the device. In addition, the influence of external vibration and temperature change is mitigated, and stable holding is achieved without causing microbending.

In particular, according to the first aspect of the invention, since the sheet is entirely formed, the sheet is thin, and since the whole can be bent and deformed due to the soft resin, the mounting density can be increased, A device using this holding structure can be downsized.

[0015]

Embodiment 1 FIG. 1 is an embodiment according to the invention described in claim 1 and is a plan view showing a holding structure of an optical fiber, and FIG. 2 is AA of FIG.
It is sectional drawing which follows the line.

The optical fiber holding structure of the first embodiment is
The long optical fibers 1 are circularly circulated so that they do not overlap each other and are not bulky in the thickness direction, and the circling positions are arranged so as to be displaced from each other in plan view. 1 is held by being sealed with a soft resin 2 in a sheet shape.

The above-mentioned soft resin 2 is applied, for example, because a silicon-based resin has an advantage that it is stable without being deteriorated for a long period of time, and is used. However, a urethane resin, a UV resin, an epoxy resin is used. Etc. can also be used.

Next, a manufacturing method for obtaining the optical fiber holding structure having the above structure will be described with reference to FIGS.

First, using an adhesive tape (for example, a tape made of a material such as polyester resin, polypropylene resin, polyethylene resin, and fluororesin) 3, the optical fiber 1 is circulated in an annular shape on the adhesive tape 3. At the same time, the lap positions are attached so as to be displaced from each other in a plane.

Next, a rectangular form 4 is placed from above,
In this mold 4, after applying a release agent, a soft resin
(For example, silicone rubber) is poured and applied so as to be thin and uniform throughout.

After the soft resin is cured, the form 4 and the adhesive sheet 3 are removed.

As a result, the optical fiber 1 is sealed with the soft resin 2 in a sheet form.

Therefore, the optical fiber 1 is composed of the soft resin 2
Since it is fixed at, it can be handled as a whole without being loosened. Therefore, it can be easily stored in the device.

Moreover, the soft resin 2 alleviates the effects of external vibrations and temperature changes, and holds it stably without causing microbending.

Further, since it is in the form of a sheet and is thin as a whole, it is sandwiched by a frame 6 made of a hard resin (for example, polyester resin, polypropylene resin, polyethylene resin, etc.) as shown in FIG. Then, as shown in FIG. 6, it is possible to arrange a plurality of them in parallel and mount them in the apparatus. This way
The mounting density can be significantly increased as compared with the conventional one.

Furthermore, since the soft resin 2 is used to hold the optical fiber 1, bending deformation is possible to some extent. Therefore, when the space in the device is limited, as shown in FIG. 7, the device can be arranged in an arcuate curved state.

In the first embodiment shown in FIG. 1, the optical fibers 1 are circularly circulated so as not to be bulky in the thickness direction, but the positions of the optical fibers 1 are displaced from each other in a plane. , As shown in FIG.
(Fig. (A)), spiral (Fig. (B)), or drum (Fig. (C)), while arranging in a state in which the orbital positions are shifted in plan view, It is also possible to seal with the soft resin 2.

Embodiment 2 FIG. 9 is an embodiment according to the invention described in claim 2 and is a perspective view showing a holding structure of an optical fiber.

The holding structure of the second embodiment has a light-weight storage case 8 made of synthetic resin or another material for storing the optical fiber 1. The storage case 8 has an inner cylindrical portion 8
The outer cylindrical portion 8b, the outer cylindrical portion 8b, and the bottom portion 8c connecting the two portions 8a and 8b are formed in a concave shape in cross section, and the inner cylindrical portion 8a is provided with two mounting portions 8d for screwing.

Then, the optical fiber 1 is accommodated in a state in which the optical fiber 1 is wound from the opening side of the accommodating case 8 and the soft resin 2 is accommodated therein.
It is sealed and held by.

As the soft resin 2 described above, a silicon-based resin is applied as in the case of the first embodiment, but a urethane rubber or the like may be used.

Next, a manufacturing method for obtaining the optical fiber holding structure having the above structure will be described.

First, as shown in FIG. 10 (a), the optical fiber 1 is wound around a drum or the like in a free state where no tension is applied.

Subsequently, as shown in FIG. 3B, the optical fiber 1 bundled in the annular shape is placed in the housing case 8.

Next, the soft resin 2 is injected from above,
This soft resin 2 is cured.

As a result, the optical fiber 1 is stored in the storage case 8
It is in a state of being integrally sealed with the soft resin 2 inside.

In this way, the optical fiber can be handled integrally without being scattered, so that it can be easily arranged in the apparatus.

Further, since the optical fiber 1 is wound up without applying excessive tension and is sealed with the soft resin 2, the influence of external vibration and temperature change is mitigated, and micro bending etc. It is stably maintained without causing.

In the second embodiment, the optical fiber 1
Is used as it is stored in the storage case 8, but the storage case 8 is regarded as a mere formwork, and the optical fiber 1 sealed with the soft resin 2 is removed from this formwork and used. It is also possible to do so.

In this case, since the entire body can be bent and deformed to some extent, when the space in the apparatus is limited, the apparatus can be arranged in a curved state.

[0041]

According to the present invention, the following effects can be obtained.

(1) In the inventions according to claims 1 and 2, since the optical fiber is sealed with the soft resin, the entire optical fiber can be handled integrally without being scattered. Therefore, it can be easily arranged in the device.

Moreover, the soft resin alleviates the effects of external vibration and temperature change, and the optical fiber is held stably without causing micro-bending.

(2) Particularly, in the invention according to claim 1, since it is in the form of a sheet as a whole, it is thin and
Since the entire structure can be bent and deformed, the mounting density can be increased, and the device using this holding structure can be downsized.

[Brief description of drawings]

FIG. 1 is a plan view showing an optical fiber holding structure according to a first embodiment.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a plan view for explaining a manufacturing method for obtaining the optical fiber holding structure of the first embodiment.

4 is a cross-sectional view taken along the line BB of FIG.

FIG. 5 is a plan view showing a modified example of the optical fiber holding structure according to the first embodiment.

FIG. 6 is a perspective view showing a state in which a plurality of optical fiber holding structures of FIG. 5 are arranged in parallel.

FIG. 7 is a perspective view showing a state where the optical fiber holding structure of FIG. 1 is bent.

FIG. 8 is a perspective view showing a modified example of the optical fiber holding structure of the first embodiment.

FIG. 9 is a perspective view showing a holding structure for an optical fiber according to a second embodiment.

FIG. 10 is a perspective view for explaining a manufacturing method for obtaining the optical fiber holding structure of the second embodiment.

FIG. 11 is a perspective view showing a conventional example in which an optical fiber is wound on a reel.

[Explanation of symbols]

1 ... Optical fiber, 2 ... Soft resin, 3 ... Adhesive tape, 4 ...
Formwork, 6 ... Frame, 8 ... Storage case.

Claims (2)

[Claims] 1. An optical fiber holding device, characterized in that the optical fibers are arranged with their circling positions displaced from each other in a plane and are sealed and held in a sheet shape with a soft resin. Construction. 2. An optical fiber holding structure, characterized in that the optical fiber is held in a state of being wound in an annular bundle by being sealed with a soft resin.