JP2001356222A - Manufacturing method and manufacturing device for multi-fiber bundled type fiber grating - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a multi-batch type grating having stable characteristics by uniformizing tension exerted on individual optical fibers when a grating is formed in a multi-fiber bundled type optical fiber. SOLUTION: In the method for manufacturing the multi-fiber bundled type fiber grating wherein the grating is formed in the multi-fiber bundled type optical fiber which is formed by coating plural optical fibers arranged in parallel at a prescribed pitch, a coating removing process for removing the coating of the end of the multi-fiber bundled type optical fiber, a stretching process for impressing prescribed tension in the axial direction of the fiber to all optical fibers in which glass is exposed by removing the coating, and an irradiating process for making light having a wavelength which generates the change of a refractive index irradiate onto all optical fibers in which glass is exposed after the tensile process are included.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for manufacturing a multi-core fiber grating for manufacturing an optical waveguide grating by forming a refractive index modulation in a core region of an optical waveguide such as an optical fiber.

[0002]

2. Description of the Related Art Conventionally, for example, Japanese Patent Application Laid-Open No. H11-32665.
As disclosed in Japanese Patent Laid-Open Publication No. 5 (1993) -5, a multi-core optical fiber (hereinafter, referred to as a “tape fiber”) in which a plurality of optical fiber strands are arranged in parallel at a predetermined pitch, coated, and formed in a tape shape Is known). In order to form a grating on this tape fiber, the following method is employed.

That is, at an intermediate position not including the end of the tape fiber, the coating is removed using a cutter such as a cutter to expose a plurality of optical fibers. Next, each of the tape portions sandwiching the exposed plurality of optical fiber wires is gripped by a fiber holder, and the exposed plurality of optical fiber wires are irradiated with light having a wavelength capable of causing a change in the refractive index. Thereby, a grating can be formed collectively for a plurality of optical fiber wires.

When a grating is formed on such a tape fiber, since the tension applied to each optical fiber affects the characteristics, a fiber grating having the same characteristics is used for all the optical fibers. It is extremely important to make the tension uniform on all the optical fiber strands in order to make them.

[0005]

However, in the conventional tape fiber, in the process of arranging a plurality of optical fiber wires in parallel at a predetermined pitch, applying a coating, and forming a tape, non-identical residual stress is present at each core. Therefore, the tension applied to each optical fiber is not uniform. For this reason, in the grating forming method disclosed in the above-mentioned publication, the residual stress is released at the stage where the coating of the intermediate portion of the tape fiber is removed, and the tension applied to each optical fiber becomes uneven, and each optical fiber becomes uneven. A length shift occurs between the fiber strands.

Empirically, removing the coating at an intermediate position not including the end of the tape fiber lengthens the central optical fiber in the width direction of the tape fiber, causing slack. It is said that this is because the degree of shrinkage of the resin at the intermediate position not including the end of the tape fiber is larger on the inside than on the outside when the tape is formed. In the tape fiber making process, the difference in the length of each optical fiber can be reduced to 2 mm per meter by carefully setting the conditions for tape conversion. Will occur.

As described above, usually, a maximum of 5 mm
When the coating at the intermediate position not including the end of the tape fiber having a length difference of 40 mm is removed in the fiber axis direction by 40 mm, the difference between the maximum value and the minimum value of the tension applied to each optical fiber is 49903. 3 [dyn] (50 g weight). On the other hand, the wavelength change rate of the grating is 980.6
Since it is about 1.0 × 10 ⁻⁵ per 65 [dyn] (1 g weight), the center wavelength is 1550 nm, and the tension is 49033.
1550 × 5 when 3 [dyn] (50 g weight)
A wavelength shift of 0 × 1.0 × 10 ⁻⁵ = 0.775 nm occurs between the fibers.

In the technique disclosed in the above publication, when forming a grating on a tape fiber, a method of removing a coating on an intermediate portion of the tape fiber is adopted. There is tape coverage at both ends of the wire. For this reason, even if the tape portions at both ends are pulled, since the optical fiber strands having a difference in wire length are pulled at one time, the tension difference applied to each optical fiber strand cannot be eliminated.

[0009] Furthermore, it is not impossible to make a tape fiber so as to minimize the length deviation,
There is a problem that the cost increases. In addition, since it is technically difficult to reduce the length deviation to zero, it is difficult to make the characteristics of the grating uniform with the conventional technology.

The present invention has been made in view of such circumstances, and when forming a grating in a multi-core optical fiber, the tension applied to each of the optical fibers is made uniform so that the multi-core optical fiber is made multi-core. It is an object of the present invention to provide a multi-core batch type fiber grating manufacturing method and a manufacturing apparatus which can collectively obtain gratings having stable characteristics.

[0011]

According to a first aspect of the present invention, there is provided a multi-core batch type fiber grating manufacturing method, wherein a multi-core optical fiber formed by coating a plurality of optical fibers arranged in parallel at a predetermined pitch is provided. A method for manufacturing a multi-core optical fiber grating for forming a grating on a collective optical fiber, comprising: a coating removing step of removing a coating on an end of the multi-core optical fiber; and removing the coating to expose the glass. A tensioning step of applying a predetermined tension in the fiber axis direction to all the optical fibers, and irradiating light having a wavelength capable of causing a change in the refractive index to all the optical fibers whose glass is exposed after the tensioning step. A configuration including an irradiation step is adopted.

As described above, by removing the coating on the end portion of the multi-core optical fiber, the residual stress applied to each optical fiber can be released. Further, by applying a predetermined tension in the fiber axis direction, the tension applied to each optical fiber can be made uniform. As a result, it is possible to obtain a grating with stable characteristics in a multi-core optical fiber.

According to a second aspect of the present invention, there is provided the method of manufacturing a multi-core collective fiber grating according to the first aspect, wherein each of the optical fiber strands of the multi-core collective optical fiber having undergone the irradiation step and any one of the optical fibers before and after the irradiation. A configuration including a connection step of fusion-splicing the element wire is adopted.

As described above, by fusion-splicing each of the optical fiber strands of the set of multi-core optical fibers after the irradiation step and one of the optical fiber strands before and after the irradiation,
It is possible to obtain a multicore optical fiber in which a grating is formed in an intermediate portion.

According to a third aspect of the present invention, there is provided the method of manufacturing a multi-core optical fiber grating according to the first or second aspect, wherein the multi-core optical fiber after the irradiation step is divided into individual optical fiber wires. A configuration including steps is adopted.

As described above, after the irradiation step is completed, the multi-core collective optical fiber is divided into individual optical fiber strands.
It is possible to form a grating for a plurality of optical fiber wires at once. Conventionally, when a single-core fiber grating is formed, it has to be set one by one in a manufacturing apparatus, and the operation is complicated. However, according to the present invention, a plurality of optical fiber Since processing is possible, work efficiency can be improved.

According to a fourth aspect of the present invention, there is provided an apparatus for manufacturing a multi-core optical fiber grating, wherein the multi-core optical fiber is formed by coating a plurality of optical fibers arranged in parallel at a predetermined pitch. An apparatus for manufacturing a multi-core collective fiber grating for forming a grating, comprising: a first fiber holder for mounting a plurality of optical fibers in which glass is exposed by removing an end portion of the multi-core collective optical fiber. A first fixing means for fixing a plurality of optical fibers mounted on the first fiber holder, a second fiber holder for mounting a coated portion or a glass portion of the multi-core optical fiber, and a second fiber holder Second fixing means for fixing the covering portion or the glass portion of the multi-core optical fiber placed on the optical fiber, and a tensioner for applying a predetermined tension to each of the fixed optical fibers. A configuration with a door.

As described above, since a predetermined tension is applied in the axial direction of the fiber after removing the coating of the end portion of the multi-core collective optical fiber, the residual stress applied to each optical fiber is released, and then each optical fiber is released. Can be made uniform. As a result, it is possible to obtain a grating with stable characteristics in a multi-core optical fiber.

According to a fifth aspect of the present invention, in the multi-core batch type fiber grating manufacturing apparatus according to the fourth aspect, the first fixing means comprises: an axis orthogonal to a surface of the first fiber holder on which the optical fiber is placed; A pressing means for pressing all the optical fibers placed along this axis evenly is adopted.

As described above, since the pressing means presses all the optical fibers vertically toward the first fiber holder, it is possible to prevent the displacement of the optical fibers and to fix the optical fibers at an appropriate position. . In particular, when the optical fiber is placed on the placement means, the optical fiber may be displaced in the fiber axis direction. Such displacement of the optical fiber can be prevented by the pressing means.

According to a sixth aspect of the present invention, in the multi-core batch type fiber grating manufacturing apparatus according to the fifth aspect, the pressing means has a configuration in which the pressing force on the optical fiber placed above is variable.

As described above, since the force for pressing the optical fiber can be increased or decreased, the optical fiber is pulled up to the moment of sliding while pressing, and the pressing force by the pressing means is further increased to fix the optical fiber. Light can be applied. This makes it possible to obtain a grating having stable characteristics in a multi-core optical fiber.

According to a seventh aspect of the present invention, in the multi-fiber bundled fiber grating manufacturing apparatus according to any one of the fourth to sixth aspects, the pulling means grips a coated portion of the multi-fiber bundled optical fiber. A configuration including a gripping means and a moving means for moving the gripping means so as to apply a predetermined tension in the fiber axis direction is adopted.

As described above, since the moving means always moves the optical fiber by a predetermined distance at once,
It is possible to always make the tension applied to the multi-core optical fiber uniform.

According to an eighth aspect of the present invention, in the multi-core batch type fiber grating manufacturing apparatus according to any one of the fourth to seventh aspects, the first fiber holder is provided with an optical fiber for mounting the optical fiber. A V-groove for regulating the position in the direction perpendicular to the axis of the fiber is provided.

With this configuration, since the position of the optical fiber in the direction perpendicular to the axis of the optical fiber is regulated, it is possible to prevent the optical fiber from shifting in the direction perpendicular to the axis when the optical fiber is pulled. it can.

According to a ninth aspect of the present invention, in the multi-core batch type fiber grating manufacturing apparatus according to any one of the fourth to eighth aspects, a plurality of first fixing means are provided on the first fiber holder. When fixing the optical fiber, the first
An end face of the fiber holder on the second fiber holder side;
A configuration is adopted in which the end face of the fixing means on the second fiber holder side coincides with the fiber axis direction.

As described above, since the end face of the first fiber holder on the side of the second fiber holder and the end face of the first fixing means on the side of the second fiber holder coincide with each other in the fiber axis direction, a plurality of optical fibers can be connected. At the time of fixing, it is possible to prevent the fiber from being bent in the up, down, left, and right directions, or from becoming loose.

According to a tenth aspect of the present invention, in the multi-fiber bundled fiber grating manufacturing apparatus according to any one of the fourth to ninth aspects, the second fixing means is mounted on the second fiber holder. When fixing the covering portion or the glass portion of the collective optical fiber, the first
A configuration is adopted in which the end face on the fiber holder side and the end face on the first fiber holder side of the second fixing means coincide with the fiber axis direction.

As described above, since the end face of the second fiber holder on the first fiber holder side and the end face of the second fixing means on the first fiber holder side are aligned in the fiber axis direction, the multi-core collective light is used. When fixing the coated portion or the glass portion of the fiber, it is possible to prevent the fiber from being bent in the up, down, left, and right directions and from becoming loose.

[0031]

Embodiments of the present invention will be described below with reference to the drawings. In each of the drawings, the same elements are denoted by the same reference numerals, and redundant description will be omitted.
Also, the dimensional ratios in the drawings do not always match those described.

FIG. 1 is an exploded perspective view of an apparatus for manufacturing a multicore fiber grating according to an embodiment of the present invention. FIG. 2 is an enlarged perspective view of a part of FIG.
In the apparatus for manufacturing a multicore fiber grating according to the present embodiment, the first fiber holder 1, the second fiber holder 2, the first fixing means 3, and the second fixing means 4 are provided on the base 5. Have been. Further, the base 5 is provided with gripping means 6 for gripping the coated portion or the glass portion of the multicore optical fiber α, and moving means 7 for moving the gripping means 6 by a predetermined distance in the fiber axis direction. . The first fiber holder 1 and the second fiber holder 2 are provided with a pair of guide pins 8 parallel to the fiber axis so as to sandwich the optical fiber. The diffraction grating holder 9 is positioned by the pair of guide pins 8.

As shown in FIG. 2, the first fiber holder 1 has a cross section perpendicular to the fiber axis direction formed in a substantially convex shape, and the uppermost surface 1a at the highest position has a plurality of light beams. In order to place the fiber β, the cross section is V-shaped.
A plurality of grooves 1b are provided. A plurality of optical fibers β (glass portions) from which the coating has been removed can be placed in the V-groove 1b. Also, two guide pins 8 are respectively engaged on a pair of guide pin mounting surfaces 1d which are located below the uppermost surface 1a and have the same height with respect to the lowermost surface 1c. A groove 1e is provided. The guide groove 1e is
The cross section is formed in a substantially V shape. Note that the set of guide pin mounting surfaces 1d may have different heights.

As shown in FIG. 2, the second fiber holder 2 has a cross section perpendicular to the fiber axis direction formed in a substantially convex shape. In order to mount the mold optical fiber α, a groove 2b having a substantially rectangular cross section is provided. Also, two guide pins 8 are respectively engaged with a pair of guide pin mounting surfaces 2d located below the uppermost surface 2a and having the same height with respect to the lowermost surface 2c. A groove 2e is provided. The guide groove 2e has a substantially V-shaped cross section. Note that the set of guide pin mounting surfaces 2d may have different heights. Further, in the present embodiment, the cross section of the groove 2b is formed in a substantially rectangular shape in order to mount the tape portion of the multi-core collective optical fiber α. Can be formed in a V-shape in order to place the groove 2b.

The first fixing means 3 includes the first fiber holder 1
Axis 3a orthogonal to the uppermost surface 1a of the optical fiber, and pressing means 3b for uniformly pressing all the optical fibers β along the axis 3a.
And The pressing means 3b is formed in a substantially block shape, and has holes 3c at both ends through which the shaft 3a passes. Further, it has a predetermined weight for pressing the optical fiber β. By changing the number of the pressing means 3b, the force for pressing the optical fiber β can be changed. Further, in the present embodiment, two first fixing means 3 are provided continuously in the fiber axis direction so that the fixing position can be changed according to the length of the optical fiber β.

A pair of fixing screws 3d fix the pressing means 3b to the base 5. The fixing screw 3d has a spring (not shown), and can change the force with which the pressing means 3b presses the optical fiber β according to the amount of screwing. It is also possible to use a push-pull gauge in place of the fixing screw 3d.

As described above, in the present embodiment, since the force for pressing the optical fiber can be increased or decreased, the optical fiber is pulled to the moment of sliding while pressing, and the number of pressing means 3b is reduced. The pressing force can be increased by increasing or increasing the screwing amount of the fixing screw 3d, and light can be emitted after fixing the optical fiber. This makes it possible to obtain a grating having stable characteristics in a multi-core optical fiber.

Further, since the pressing means 3b presses all the optical fibers β vertically toward the uppermost surface 1a of the first fiber holder 1, the displacement of the optical fibers β is prevented, and the optical fibers β are properly positioned. Can be fixed. In particular, when the optical fiber β is placed in the V-groove 1b as the placing means, the optical fiber β may be displaced in the fiber axis direction. Can be prevented.

One end of the second fixing means 4 is rotatably supported by the base 5 so as to sandwich the coated portion of the multi-core optical fiber α placed in the groove 2b of the second fiber holder 2. Fixed to.

The gripping means 6 grips the coated portion of the multi-core optical fiber α by a rotatably supported gripping member 6a, and the moving means 7 moves the gripping means 6 by a predetermined distance in the fiber axis direction. . That is, the moving means 7 includes the first
The optical fiber β fixed by the fixing means 3 is pulled via the gripping means 6, and tension is applied in a range from the time when the optical fiber β is pulled to the moment when the optical fiber β starts to slide. The moving means 7 will be described with reference to FIG. As shown in FIG. 6, the moving means 7 includes a micrometer head 71.
A micrometer head support member 72 fixed to the base 5 and supporting the micrometer head 71; and a spring 73 connecting the micrometer head support member 72 and the holding means 6 to each other. The end 71 a of the micrometer head 71 on the gripping means 6 side abuts on the gripping means 6. In FIG. 6, when the micrometer head 71 is moved in the direction of A, the end 71 a tends to move away from the gripping means 6.
However, the holding means 6 and the micrometer head support member 7
2 is provided between the spring 73 and the spring 73.
The gripping means 6 moves in the direction A by the tension of. The tension of the spring 73 is linearly applied to the holding means 6 with the operation of the micrometer head 71 within a range not exceeding the frictional force of the first fixing means 3. When the tension of the spring 73 exceeds the frictional force in the first fixing means 3, the optical fiber β
Begins to slip.

As described above, since the moving means 7 always moves the holding means 6 by a predetermined distance, it is possible to always make the tension applied to the multi-core optical fiber uniform. Note that the moving means 7 may adopt a configuration in which the gripping means 6 is moved by a combination of a bolt and a nut.

As shown in FIG. 3A, when the first fixing means 3 fixes the plurality of optical fibers β placed on the first fiber holder 1, the second fiber of the first fiber holder 1 is fixed. The end face 1f on the holder 2 side and the second fixing means 3
The end face 3e on the fiber holder 2 side coincides with the fiber axis direction. When the second fixing means 4 fixes the coated portion of the multi-core optical fiber α placed on the second fiber holder 2, an end face 2 f of the second fiber holder 2 on the first fiber holder 1 side, The end face 4a of the second fixing means 4 on the first fiber holder 1 side coincides with the fiber axis direction.

For example, as shown in FIG. 3B, the end face 3f of the first fixing means 3 on the side of the second fiber holder 2 is closer to the end face 1f of the first fiber holder 1 on the side of the second fiber holder 2. If it is shifted to the opposite side from the two-fiber holder 2, the optical fiber β will bend upward. As shown in FIG. 3C, the end face 3e of the first fixing means 3 on the side of the second fiber holder 2 is opposed to the end face 3f of the first fiber holder 1 on the side of the second fiber holder 2. If it shifts to the second side, the optical fiber β will bend downward. In the present embodiment, the second fiber holder 2 of the first fiber holder 1
When the plurality of optical fibers β are fixed, the fiber bends in the vertical and horizontal directions because the end face 1 f of the first side and the end face 3 e of the first fixing means 3 on the side of the second fiber holder 2 coincide with each other in the fiber axis direction. Or loosening can be prevented.

Similarly, the end face 2f of the second fiber holder 2 on the first fiber holder 1 side and the end face 4a of the second fixing means 4 on the first fiber holder 1 side coincide with the fiber axis direction. When the covering portion of the multi-core collective optical fiber α is fixed, it is possible to prevent the fiber from bending in the vertical and horizontal directions and from becoming loose.

Next, a description will be given of a method of forming a grating using the apparatus for manufacturing a multi-core batch type fiber grating according to the above-described embodiment. First, the coating on the end of the multi-core optical fiber α is removed. By removing the coating from the end in this way, the residual stress can be released. Next, as shown in FIG. 4, the optical fiber β whose glass has been exposed by removing the coating is placed in the V-groove 1b of the first fiber holder 1, and the coated portion of the multi-core optical fiber α is removed. It is placed in the groove 2b. Next, the hole 3c of the pressing means 3b is
a to hold down the optical fiber β. Furthermore, the second
By rotating the fixing means 4, the coated portion of the multicore optical fiber α is fixed. Furthermore, the coated portion of the multi-core optical fiber α is gripped by the gripping member 6a.

Next, when the diffraction grating holder 9 is placed on the pair of guide pins 8, the structure shown in FIG. 5 is obtained. Next, the holding means 6 is moved by the moving means 7 to the first fiber holder 1.
Is moved a predetermined distance in the direction of the second fiber holder 2. As shown in FIG. 6, when the micrometer head 71 is moved in the direction of A, the end 71 a tends to move away from the gripping means 6. However, since the spring 73 is provided between the holding means 6 and the micrometer head support member 72, the holding means 6 moves in the direction A by the tension of the spring 73. The tension of the spring 73 is linearly applied to the holding means 6 with the operation of the micrometer head 71 within a range not exceeding the frictional force of the first fixing means 3. Spring 7
3 exceeds the frictional force of the first fixing means 3,
The optical fiber β starts to slip. At this time, the first fixing means 3
Is fixed so that the optical fiber β does not slip.

As described above, since the optical fiber β is fixed at the moment when the optical fiber β fixed by the first fixing means 3 starts sliding, the tension of each core can be equalized.

Finally, light having a wavelength capable of causing a change in the refractive index is applied to all the optical fibers β via the diffraction grating 9a held in the diffraction grating holder 9.

As described above, the residual stress applied to each optical fiber can be released by removing the coating on the end of the multi-core optical fiber. Further, by applying a predetermined tension in the fiber axis direction, the tension applied to each optical fiber can be made uniform. As a result, it is possible to obtain a grating with stable characteristics in a multi-core optical fiber.

In the above description, the method of removing the coating on the end of the multi-core optical fiber has been described. However, it is intended to form a grating at the intermediate portion of the multi-core optical fiber as in the prior art. In such a case, the optical fiber strands of a set of multi-core optical fibers obtained by the above method are fusion-spliced.

As described above, by fusion-splicing the optical fiber strands of a set of multi-core collective optical fibers that have undergone the irradiation step, the multi-core collective optical fiber having a grating formed in the middle portion is formed. It is possible to obtain.

When a so-called single-core fiber grating is required, the multi-core optical fiber obtained by the above method is divided into individual optical fiber strands.

As described above, after the irradiation step, the multi-core collective optical fiber is divided into individual optical fiber wires,
It is possible to form a grating for a plurality of optical fiber wires at once. Conventionally, when a single-core fiber grating is formed, it has to be set one by one in a manufacturing apparatus, and the operation is complicated. However, according to the present invention, a plurality of optical fiber Since processing is possible, work efficiency can be improved.

[0054]

As described above, the method for manufacturing a multi-core optical fiber grating according to the present invention provides a multi-core optical fiber grating formed by covering a plurality of optical fibers arranged in parallel at a predetermined pitch. A method of manufacturing a multi-core optical fiber grating for forming a grating on an optical fiber, comprising: a coating removing step of removing a coating on an end portion of the multi-core optical fiber; and a glass being exposed by removing the coating. A tensioning step of applying a predetermined tension in the fiber axis direction to all optical fibers, and an irradiation of irradiating light having a wavelength capable of causing a change in refractive index to all the optical fibers whose glass is exposed after the tensioning step. And a configuration including steps.

As described above, by removing the coating on the end of the multi-core optical fiber, the residual stress applied to each optical fiber can be released. Further, by applying a predetermined tension in the fiber axis direction, the tension applied to each optical fiber can be made uniform. As a result, it is possible to obtain a grating with stable characteristics in a multi-core optical fiber.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of an apparatus for manufacturing a multicore fiber grating according to an embodiment of the present invention.

FIG. 2 is an enlarged perspective view of the vicinity of first and second fiber holders.

FIG. 3 is a sectional view showing a state where an optical fiber is fixed.

FIG. 4 is a perspective view showing a state where a multi-core optical fiber is mounted.

FIG. 5 is a perspective view showing a state in which a multi-core collective optical fiber is fixed.

FIG. 6 is a schematic configuration diagram of a moving unit.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... 1st fiber holder, 2 ... 2nd fiber holder, 3
... first fixing means, 4 ... second fixing means, 5 ... substrate, 6 ... holding means, 7 ... moving means, α ... multi-core optical fiber, β
... optical fiber.

Continued on the front page (72) Inventor Ken Hashimoto 1 Tayacho, Sakae-ku, Yokohama-shi, Kanagawa Prefecture Inside Sumitomo Electric Industries, Ltd. (72) Inventor Maki Omura 1-Tayacho, Sakae-ku, Yokohama, Kanagawa Prefecture F term in Yokohama Works (reference) 2H050 AC82 AC84 AD00

Claims (10)

[Claims] 1. A multi-core package fiber grating manufacturing method for forming a grating on a multi-core package optical fiber formed by coating a plurality of optical fibers arranged in parallel at a predetermined pitch. A coating removing step of removing the coating of the end of the multi-core optical fiber; and a tensioning step of applying a predetermined tension in the fiber axis direction to all the optical fibers from which the coating has been removed and the glass has been exposed. And a irradiating step of irradiating light having a wavelength capable of causing a change in the refractive index to all the optical fibers in which the glass is exposed after the pulling step. . 2. The method according to claim 1, further comprising a splicing step of fusion splicing each of the optical fiber strands of the multi-core optical fiber after the irradiation step and one of the optical fiber strands before and after the irradiation. 2. The method for producing a multicore fiber grating according to claim 1. 3. The manufacturing method of a multi-core fiber grating according to claim 1, further comprising a dividing step of dividing the multi-core optical fiber after the irradiation step into individual optical fiber wires. Method. 4. A multi-core batch fiber grating manufacturing apparatus for forming a grating on a multi-core batch optical fiber formed by coating a plurality of optical fiber strands arranged in parallel at a predetermined pitch. And a first fiber holder for mounting a plurality of optical fibers, the coating of which is removed from an end of the multi-core optical fiber, and exposing the glass; and the plurality of optical fibers mounted on the first fiber holder. First fixing means for fixing an optical fiber; a second fiber holder for mounting a coated portion or a glass portion of the multi-core optical fiber; and the multi-core collective light mounted on the second fiber holder. A second fixing means for fixing a coated portion or a glass portion of the fiber; and a pulling means for applying a predetermined tension to each of the fixed optical fibers. Type fiber grating fabrication apparatus. 5. The first fixing means uniformly presses an axis orthogonal to a surface of the first fiber holder on which the optical fiber is placed, and all the optical fibers placed along the axis along the axis. 5. A pressing means, comprising:
The multi-core batch type fiber grating manufacturing apparatus described in the above. 6. The pressing means according to claim 5, wherein the pressing force on said optical fiber is variable.
The multi-core batch type fiber grating manufacturing apparatus described in the above. 7. The pulling means includes a gripping means for gripping the coated portion of the multi-core optical fiber, and a moving means for moving the gripping means so as to apply a predetermined tension in the fiber axis direction. The multi-core batch type fiber grating manufacturing apparatus according to any one of claims 4 to 6, wherein: 8. The optical fiber according to claim 4, wherein the first fiber holder is provided with a V-groove for regulating a position in a direction perpendicular to an axis of the optical fiber with respect to the optical fiber to be placed.
The multi-core batch type fiber grating manufacturing apparatus according to any one of claims 1 to 7. 9. When the first fixing means fixes the plurality of optical fibers placed on the first fiber holder,
The end face of the first fiber holder on the side of the second fiber holder and the end face of the first fixing means on the side of the second fiber holder coincide with each other in the fiber axis direction. 8. The multi-core collective fiber grating manufacturing apparatus according to any one of 8. 10. The first fiber holder of the second fiber holder when the second fixing means fixes a covering portion or a glass portion of the multi-core optical fiber placed on the second fiber holder. The end face on the side of the first fiber holder and the end face on the side of the first fiber holder of the second fixing means coincide with each other in the fiber axial direction.
The multi-core batch type fiber grating manufacturing apparatus according to any one of the above.