JPH06230246A - Optical fiber array, parts for arraying the same and production of optical fiber array - Google Patents

Abstract

PURPOSE:To provide the optical fiber array which does not require the use of X-axis and Y-axis optical stages at the time of aligning polarization planes by rotating the polarization plane-maintaining optical fibers, the parts for arraying the optical fiber array and the process for production of the optical fiber array. CONSTITUTION:A guide 20 for optical fibers is fixed onto a upper plane part 18 of a V-groove base plate 10. The polarization plane-maintaining optical fibers 30 are then inserted into the V-groove base plate 10 from behind and optical fiber exposed parts 31 are placed in the V-grooves 11. The polarization planes of the polarization plane-maintaining optical fibers 30 are aligned by rotating the polarization plane-maintaining optical fibers 30 with the space between the V-groove base plate 10 and the rear surface 21 of the guide 20 for the optical fibers as a guide for rotation of the optical fibers in the state of placing the optical fiber exposed parts 31 in the V-grooves 11. An optical fiber-retaining base plate 40 is thereafter provided on the optical fiber exposed parts 31 and the polarization plane-maintaining optical fibers 30 are fixed by a resin type adhesive 60.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical fiber array in which a plurality of optical fibers are aligned and fixed, a component for the alignment, and a method of manufacturing the optical fiber array.

[0002]

2. Description of the Related Art Polarization-maintaining optical fibers are used in various fields such as communication and measurement using optical fibers. This polarization-maintaining optical fiber has the characteristic of being able to preserve the polarization plane of propagating light, and has applications in various sensors that utilize the polarization and phase characteristics of light, and in coherent communication. Has been done.

Various aligning components are used to arrange a plurality of polarization-maintaining optical fibers at predetermined intervals so as to be integrally fixed as an optical fiber array. And, when connecting a plurality of polarization-maintaining optical fiber arrays aligned in this way with other optical components,
It is necessary to hold the polarization planes of a plurality of polarization-maintaining optical fibers at desired angular positions.

For this reason, conventionally, for example, as shown in FIG. 3, a plurality of polarization-maintaining optical fibers are held at desired angular positions and are aligned at predetermined intervals.

That is, first, as shown in FIG. 3A, the resin coating portion 39 of the polarization-maintaining single-mode fiber 30 is placed on the concave portion 15 of the V-groove substrate 10 and the resin coating portion 39 of the polarization-maintaining single-mode fiber 30 is formed. The polarization-maintaining optical fiber 30 is positioned above the V-groove substrate 10 so that the optical fiber exposed portions 31 exposed from the resin coating portion 39 by removal are positioned on the V-groove 11.

Next, the polarization-maintaining optical fiber 30 is moved in the X-axis direction 70 and the Y-axis direction 80 using an optical stage (not shown) to expose the optical fiber, as shown in FIG. 3B. The polarization plane-maintaining optical fiber 30 is rotated in a state where 31 is aligned in the V groove 11, and the polarization plane of the polarization-plane maintaining optical fiber 30 is aligned.

Thereafter, as shown in FIG. 3C, an optical fiber pressing board 50 is provided on the optical fiber exposed portion 31.

Next, as shown in FIG. 3D, a resin adhesive 60 is introduced from an adhesive injection port 55 formed in the optical fiber pressing substrate 50, and the resin adhesive 60 is cured by heating, irradiation of ultraviolet rays, or the like. And the polarization-maintaining optical fiber 30,
The V-groove substrate 10 and the optical fiber pressing substrate 50 are integrally fixed.

After that, the end faces of the polarization-maintaining optical fiber 30 are exposed by polishing the front ends of the polarization-maintaining optical fiber 30, the V-groove substrate 10 and the optical fiber pressing substrate 50 that are integrally fixed.

The polarization-maintaining optical fiber 30 is provided with stress applying portions 33 on both sides of the core 34 in order to preserve the polarization plane of the light, and the optical fiber exposed portion 31 is a side surface of the V groove 11. 12, 13 and optical fiber pressing board 50
Is fixed in contact with the three surfaces of the lower surface 51 of the.

[0011]

However, in such a conventional method, each polarization-maintaining optical fiber 3 is used.
At least two X-axis and Y-axis optical stages are required for each 0 (in some cases, two more optical stages are required to adjust the tilt in both the X-axis and Y-axis directions). At least, an optical stage having twice the number of cores of the polarization maintaining optical fiber 30 used in the optical fiber array is required. Since such an optical stage is expensive, the jig for assembling the optical fiber array becomes very expensive as the number of cores of the polarization-maintaining optical fiber 30 increases.

Further, it is necessary to operate at least the X-axis and Y-axis optical stages for each polarization-maintaining optical fiber 30, and there is a problem that alignment using such an optical stage takes a very long time. It was

Further, adjacent polarization-maintaining optical fibers 30 are also provided.
The interval (that is, the pitch of the V groove 11) is several hundred μm
If the number of cores of the polarization-maintaining optical fiber 30 is reduced to 8
In the above case, there is a problem that the space for disposing the optical stage can no longer be secured and the optical fiber array cannot be assembled even by the conventional method.

Further, even when the optical fiber is not a polarization-maintaining optical fiber but a normal optical fiber having no stress applying portion, these optical fibers are placed in the V groove. There is also a problem that it is necessary to use a special jig for it and it takes time.

Therefore, an object of the present invention is to rotate the polarization plane-maintaining optical fiber to perform polarization plane alignment, and
An object of the present invention is to provide an optical fiber array that does not require the use of a Y-axis optical stage, its alignment component, and a method for manufacturing the optical fiber array.

Another object of the present invention is to provide an optical fiber array in which an optical fiber can be easily mounted in a V groove, a component for aligning the optical fiber, and a method for manufacturing the optical fiber array.

[0017]

According to the present invention, a V-groove substrate having V-grooves formed therein, an optical fiber placed in the V-groove, and an optical fiber pressing member provided on the optical fiber are provided. In an optical fiber array in which and are integrally fixed, an optical fiber array is provided on the V-groove substrate, the lower surface of which is provided with a guide for an optical fiber separated from the top of the optical fiber by a predetermined distance. To be

Further, according to the present invention, a V-groove substrate having a V-groove on which an optical fiber is mounted and a V-groove substrate provided on the optical fiber for holding the optical fiber in the V-groove. An optical fiber array aligning component including an optical fiber pressing member, further comprising an optical fiber guide provided on the V-groove substrate with a lower surface thereof separated from a top portion of the optical fiber by a predetermined distance. A fiber array alignment component is obtained.

Furthermore, according to the present invention, a V-groove substrate having a V-groove on which a polarization-maintaining optical fiber is mounted and a lower surface of the V-groove substrate are separated from the top of the polarization-maintaining optical fiber for a predetermined period. As described above, using the space between the lower surface of the optical fiber guide provided on the V-groove substrate and the lower surface as a guide, the polarization plane alignment of the polarization plane maintaining optical fiber is performed, and then the polarization plane maintaining light. And a step of fixing the fibers to the V-grooves. In this case, preferably, an optical fiber holding member is provided on the polarization-maintaining optical fiber, and the polarization-maintaining optical fiber is in contact with three surfaces of the lower surface of the optical fiber holding member and both side surfaces of the V groove. Then, the polarization-maintaining optical fiber is fixed to the V groove.

Furthermore, according to the present invention, a V-groove substrate having a V-groove on which an optical fiber is placed, and the V-groove substrate, the lower surface of which is separated from the top of the optical fiber by a predetermined distance.
A step of inserting the optical fiber into the V groove using the space between the lower surface of the optical fiber guide provided on the groove and the guide as a guide, and then fixing the optical fiber to the V groove. And a method for manufacturing an optical fiber array, which comprises:

[0021]

In the present invention, the V-groove substrate is provided with an optical fiber guide whose lower surface is separated from the top of the optical fiber by a predetermined distance, or the lower surface is separated from the top of the optical fiber by a predetermined distance. A V-groove substrate provided with an optical fiber guide provided on the V-groove substrate, or a V-groove substrate having a V-groove on which a polarization-maintaining optical fiber is mounted;
Aligning the polarization planes of the polarization-maintaining optical fiber with the space between the lower surface of the polarization-maintaining optical fiber and the lower surface of the optical fiber guide provided on the V-groove substrate so as to be separated from the top of the polarization-maintaining optical fiber by a predetermined distance. By doing so, the optical fiber guide can be used as a guide for rotating the optical fiber, and when the polarization plane preserving optical fiber is rotated in the V groove to perform polarization plane alignment, There is no need to use an optical stage. Therefore, the jig for assembling the optical fiber array becomes inexpensive. Further, since it is not necessary to perform the alignment using the optical stage, which takes time, the assembly time is shortened and the manufacturing cost is reduced. In addition, X for each optical fiber
Since there is no need to use an optical stage for the axis and the Y axis,
There is no need to secure a space for disposing these optical stages, and therefore, there is no limitation on the number of optical fiber cores that can be assembled.

In the present invention, an optical fiber guide whose lower surface is separated from the top of the optical fiber by a predetermined distance is provided on the V-groove substrate, or the lower surface is spaced from the top of the optical fiber by a predetermined distance. By providing a guide for the optical fiber which is separately provided on the V-groove substrate, or
A V-groove substrate having a V-groove on which an optical fiber is placed,
A lower surface of an optical fiber guide provided on the V-groove substrate such that its lower surface is separated from the top of the optical fiber by a predetermined distance,
By inserting the optical fiber into the V groove using the space between them as a guide, the optical fiber guide can be used as an optical fiber insertion guide.
The optical fiber can be easily aligned in the groove,
As a result, the manufacturing cost of the optical fiber array is reduced.

In the optical fiber guide, the distance between the lower surface of the optical fiber guide and the top of the optical fiber is 5 μm or more, and the lower surface of the optical fiber guide and the upper surface of the V groove substrate on which the V groove is formed. It is preferable that the distance from the section is designed to be equal to or smaller than the diameter of the optical fiber. The distance between the bottom of the optical fiber guide and the top of the optical fiber is 5 μm
If it is smaller, it becomes difficult to insert the optical fiber into the space between the V-groove substrate and the optical fiber guide, and
There is also a problem that the end face of the optical fiber is easily chipped. Further, if the distance between the lower surface of the optical fiber guide and the upper flat surface of the V-groove substrate on which the V-groove is formed is larger than the diameter of the optical fiber, the optical fiber can go out of the V-groove. This is because it becomes impossible to reliably guide the optical fiber into the V groove.

Further, more preferably, the distance between the lower surface of the optical fiber guide and the top of the optical fiber is designed to be about ½ of the diameter of the optical fiber. For example, when a communication single-mode optical fiber having a diameter of 125 μm is used as the optical fiber, this distance is designed to be about 50 μm. This is because it is easy to insert the optical fiber into the space between the V-groove substrate and the lower surface of the optical fiber guide, and the optical fiber dances less when the polarization-maintaining optical fiber rotates.

Furthermore, more preferably, it is designed so that the distance between the lower surface of the optical fiber guide and the upper flat surface of the V-groove substrate on which the V-groove is formed is about ½ of the diameter of the optical fiber. It For example, when an optical fiber having a diameter of 125 μm is used, the distance is designed to be about 50 μm. If the distance between the lower surface of the optical fiber guide and the upper flat surface of the V-groove substrate on which the V-groove is formed exceeds about 1/2 of the diameter of the optical fiber, the optical fiber falls while rotating. Therefore, the optical fiber is twisted, and when it is bonded with a thermosetting resin, the optical fiber rotates so that the spring stretches, and the direction of the stress applying part of the optical fiber after manufacturing, that is, the polarization of the optical fiber This is because the direction is wrong.

[0026]

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

As shown in FIG. 1A, a plurality of V grooves 11 are provided in parallel with each other on the upper flat surface portion 18 of the V groove substrate 10. The polarization-maintaining optical fiber 30 communicates with the plurality of V-grooves 11 and
The V-groove substrate 10 is provided with a recess 15 for inserting the resin coating portion 39 of FIG.

Next, as shown in FIG. 1B, the V groove substrate 10 is formed.
The optical fiber guide 20 is fixed to the upper flat surface portion 18 of the. This fixing is performed by fixing the bottom surfaces of the leg portions 23 provided at both ends of the optical fiber guide 20 to both end portions of the upper flat surface portion 18 of the V-groove substrate 10 with an adhesive.

Next, as shown in FIG. 1C, the polarization-maintaining optical fiber 30 is inserted from the rear side of the V-groove substrate 10 and the resin-coated portion 39 of the polarization-maintaining optical fiber 30 is removed to coat the resin. The optical fiber exposed portion 31 exposed from the portion 39 is placed on the V groove 11. At this time, the front end face of the polarization-maintaining single-mode fiber 30 is made to substantially coincide with the front end face of the V-groove substrate 10, and the resin-coated portion 39 of the polarization-maintaining single-mode fiber 30 is inserted into the recess 15 of the V-groove substrate 10 and the optical fiber. It is housed in the space between the lower surface 21 of the guide 20.

FIG. 2 is a view of FIG. 1C seen from the front side, and an interval a is provided between the lower surface 21 of the optical fiber guide 20 and the top 35 of the optical fiber exposed portion 31 of the polarization-maintaining optical fiber 30. A space b is provided between the lower surface 21 of the optical fiber guide 20 and the upper flat surface portion 18 of the V-groove substrate 10. Polarization maintaining optical fiber 3 used in this embodiment
0 is composed of the outer cladding 32 and the central core 34, and the diameter of the optical fiber exposed portion 31, that is, the diameter of the cladding 32 is 125 μm. In this embodiment, the distance a is 50 μm and the distance b is 113 μm.
m. The polarization-maintaining optical fiber 30 is provided with stress applying portions 33 on both sides of the core 34 in order to preserve the polarization plane of light.

Next, referring again to FIG. 1C, with the optical fiber exposed portion 31 of the polarization-maintaining optical fiber 30 placed on the V groove 11, the V groove substrate 10 and the lower surface 21 of the optical fiber guide 20. The polarization-maintaining optical fiber 30 is rotated by using the space between and as a guide to rotate the polarization-maintaining optical fiber 30.
Polarization plane alignment is performed by aligning the polarization plane of 0 with a desired angular position.

In this case, since the optical fiber guide 20 is provided on the V-groove substrate 10, while the polarization-maintaining optical fiber 30 is rotating, the polarization-maintaining optical fiber 30 is V-shaped.
The side surface 12 of the V-shaped groove 11 is not separated from the groove 11,
It is positioned at a predetermined position with respect to 13. Therefore, X
The polarization plane preserving optical fiber 30 can be rotated to easily perform polarization plane alignment without using the optical axes of the axis and the Y axis.

Thereafter, as shown in FIG. 1D, an optical fiber pressing board 40 is provided on the optical fiber exposed portion 31. In this case, the front end portion of the optical fiber pressing board 40 was made to substantially coincide with the front end surface of the polarization-maintaining optical fiber 30 and the front end surface of the V-groove substrate 10.

Next, as shown in FIG. 1E, a resin adhesive 60 is introduced from an adhesive injection port 25 formed in the optical fiber guide 20. A thermosetting resin is used for the resin adhesive 60, and the resin adhesive 60 is cured by heating to integrate the polarization-maintaining optical fiber 30, the V-groove substrate 10, the optical fiber guide 20, and the optical fiber holding substrate 40. To be fixed firmly. When an ultraviolet curable resin is used as the resin adhesive 60, the resin adhesive 60 is irradiated with ultraviolet rays to cure the resin adhesive 60.

Thereafter, by polishing the front ends of the polarization-maintaining single-mode fiber 30, the V-groove substrate 10 and the optical fiber pressing substrate 40 that are integrally fixed to each other, the end faces of the polarization-maintaining optical fiber 30 are exposed so that light is emitted. Assemble the fiber array.

In the thus-assembled optical fiber array, the optical fiber exposed portion 31 is fixed in contact with the side surfaces 12 and 13 of the V groove 11 and the lower surface 41 of the optical fiber pressing substrate 40. There is.

Although a polarization-maintaining optical fiber is used as the optical fiber in this embodiment, the optical fiber array, the alignment component thereof, and the method of manufacturing the optical fiber array of the present invention are provided with a stress applying portion. It can also be applied to a non-optical fiber, and even in that case, the space between the V-groove substrate 10 and the lower surface 21 of the optical fiber guide 20 is used as an optical fiber insertion guide to facilitate the optical fiber. It can be placed in the V groove 11.

[0038]

According to the present invention, an optical fiber guide is provided on the V-groove substrate, the lower surface of which is separated from the top of the optical fiber by a predetermined distance, or the lower surface of the V groove substrate is separated from the top of the optical fiber by a predetermined distance. By providing an optical fiber guide separately provided on the V-groove substrate, or by forming a V-groove on which the polarization-maintaining optical fiber is mounted and a lower surface of the V-groove-maintaining optical fiber. The polarization plane of the polarization-maintaining optical fiber is aligned by using the space between the top and the lower surface of the optical fiber guide provided on the V-groove substrate so as to be separated from the top by a predetermined distance to guide the optical fiber guide. It can now be used as a rotation guide for an optical fiber, and uses an X-axis and Y-axis optical stage when performing polarization plane alignment by rotating a polarization-maintaining optical fiber in a V groove. That it is no longer necessary. Therefore, the jig for assembling the optical fiber array becomes inexpensive. Further, since it is not necessary to perform the alignment using the optical stage, which takes time, the assembly time is shortened and the manufacturing cost is reduced. Furthermore, since it is not necessary to use an X-axis or Y-axis optical stage for each optical fiber, it is not necessary to secure a space for disposing these optical stages, and therefore, there is no limitation on the number of optical fiber cores that can be assembled. .

In the present invention, an optical fiber guide whose lower surface is separated from the top of the optical fiber by a predetermined distance is provided on the V-groove substrate, or the lower surface is separated from the top of the optical fiber by a predetermined distance. By providing a guide for the optical fiber which is separately provided on the V-groove substrate, or
A V-groove substrate having a V-groove on which an optical fiber is placed,
A lower surface of an optical fiber guide provided on the V-groove substrate such that its lower surface is separated from the top of the optical fiber by a predetermined distance,
By inserting the optical fiber into the V groove using the space between them as a guide, the optical fiber guide can be used as an optical fiber insertion guide.
The optical fiber can be easily aligned in the groove,
As a result, the manufacturing cost of the optical fiber array is reduced.

[Brief description of drawings]

FIG. 1 is a perspective view for explaining an embodiment of the present invention.

FIG. 2 is a front view of FIG. 1C.

FIG. 3 is a perspective view for explaining a conventional technique.

[Explanation of symbols]

 10 ... V-groove substrate 11 ... V-groove 12 ... Side surface 13 ... Side surface 15 ... Recessed portion 18 ... Upper flat surface portion 20 ... Optical fiber guide 21 ... Lower surface 25 ... Adhesive injection port 30 ... Polarization preserving optical fiber 31 ... Optical fiber exposure Part 32 ... Clad 34 ... Core 35 ... Top part 39 ... Resin coating part 40 ... Optical fiber pressing board 41 ... Lower surface 60 ... Resin adhesive 70 ... X-axis direction 80 ... Y-axis direction

Claims (5)

[Claims] 1. An optical fiber in which a V-groove substrate having a V-groove formed therein, an optical fiber mounted in the V-groove, and an optical fiber pressing member provided on the optical fiber are integrally fixed to each other. In the array, an optical fiber array is provided on the V-groove substrate, the lower surface of which is provided with an optical fiber guide which is separated from the top of the optical fiber by a predetermined distance. 2. A V-groove substrate having a V-groove on which an optical fiber is placed, and an optical fiber pressing member provided on the optical fiber for holding the optical fiber against the V groove. The optical fiber array aligning component, further comprising an optical fiber guide provided on the V-groove substrate, the lower surface of which is separated from the top of the optical fiber by a predetermined distance. 3. A V-groove substrate on which a V-groove for mounting a polarization-maintaining optical fiber is formed, and a V-groove substrate on the lower surface of which a lower surface is separated from the top of the polarization-maintaining optical fiber by a predetermined distance. A step of performing polarization plane alignment of the polarization-maintaining optical fiber by using a space between the lower surface of the provided optical fiber guide and the guide as a guide, and thereafter, fixing the polarization-maintaining optical fiber to the V groove. A method for manufacturing an optical fiber array, comprising: 4. The method of manufacturing an optical fiber array according to claim 3, wherein an optical fiber holding member is provided on the polarization-maintaining optical fiber, and the polarization-maintaining optical fiber is provided on the lower surface of the optical fiber holding member and the V. A method of manufacturing an optical fiber array, characterized in that the polarization-maintaining optical fiber is fixed to the V groove while being in contact with three surfaces of the groove, which are both side surfaces. 5. A V-groove substrate in which a V-groove for mounting an optical fiber is formed, and an optical fiber guide provided on the V-groove so that its lower surface is separated from the top of the optical fiber by a predetermined distance. A step of inserting the optical fiber into the V-groove using a space between the lower surface and the guide as a guide; and a step of subsequently fixing the optical fiber to the V-groove. Manufacturing method of fiber array.