JP3710624B2 - Method for manufacturing polarization maintaining optical fiber bundle - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for manufacturing an optical fiber bundle that can be used as a component of an optical signal processing system that uses polarization, and is applied to the field of optical communication.
[0002]
[Prior art]
Conventional optical fiber bundles are used in the medical field such as endoscope cameras, for example, and many optical fiber strands are packed into a glass tube, and then heated and integrated to draw an image fiber. Yes.
The fiber bundle according to the present invention relates to an optical fiber bundle that can be used as a component of an optical signal processing system using polarized waves as described above, and is different from the normal bundle fiber in the number and structure of the fibers.
[0003]
That is, if a typical example of such a polarization maintaining fiber is shown in the drawing, as shown in the cross-sectional view of FIG. 1, circular stress applying portions 2 are provided on both sides of the core 1, and the clad portion concentric with the core 1 is provided. A polarization maintaining fiber 5 having a cross section covering these in a circular shape 3 and having a polarization maintaining shaft 4 in the center axis of the core 1 and the stress applying portion 2 is known. FIG. 2 is a partially omitted cross-sectional view showing a bundle obtained by aligning the polarization angles of the five polarization planes. That is, a plurality of, for example, 10 strips of the polarization maintaining fiber 5 are manufactured and the polarization maintaining optical fiber bundle 7 is manufactured by aligning the direction of polarization in a certain direction and bonding them together with the adhesive 6.
[0004]
Conventionally, the polarization maintaining optical fiber bundle is manufactured by bundling a plurality of polarization maintaining optical fiber cores 11 whose end faces are cut as shown in FIG. Are arranged in front of the CCD camera 13 in a generally aligned state. Then, the end face of each optical fiber is confirmed on the TV monitor 14, the end faces of all optical fibers are confirmed on the TV monitor, and the polarization maintaining axes of all the optical fibers are aligned and fixed with an adhesive.
Therefore, the polarization maintaining axis is determined from the geometric pattern of the end face of the optical fiber as shown in FIG.
[0005]
[Problems to be solved by the invention]
However, when the above-described conventional method is used, it is difficult to completely align the end faces of the optical fibers. Therefore, when the end faces are imaged with a CCD camera, the end faces of the optical fibers are simultaneously imaged with all the core wires. do not do. For this reason, when adjusting the angle of the polarization maintaining axis, it is necessary to form an image for each core wire, and there is a problem that it takes a very long time to adjust the angle.
[0006]
[Means for Solving the Problems]
The present invention has been made to solve the above problems, and the invention according to claim 1 is characterized in that the angles of the polarization maintaining axes of the plurality of polarization maintaining optical fibers subjected to the end face cut are aligned. In the bundling operation, the end faces of each of the plurality of polarization maintaining optical fibers are collectively abutted against a glass plate transparent to visible light so that the positions of the end faces of the optical fibers are aligned and fixed with an adhesive. This is a method for manufacturing a polarization maintaining optical fiber bundle.
According to a second aspect of the present invention, the glass plate is made of quartz glass having a high ultraviolet transmittance, and an ultraviolet curable adhesive is used as the adhesive, and the glass plate is cured with ultraviolet light. It is a manufacturing method of the polarization-maintaining optical fiber bundle of description.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
As an embodiment of the present invention, for example, a case where 10 optical fibers are bundled will be described. As shown in FIG. 3, 10 optical fibers are bundled together, and the end face 12 is cut to maintain polarization. Then, when the bundle is fixed by aligning the angles of the holding shafts, a predetermined number of end faces of the polarization-maintaining optical fiber core 11 are aligned with the glass plate 15 and abut against the glass plate 15 to make all the optical fiber cores. The polarization maintaining optical fiber bundle having a stable structure can be easily obtained by aligning the end face positions between the optical fibers 11 and bonding and fixing the optical fiber core wires 11 with an adhesive.
[0008]
That is, when the method of the present invention is compared with the conventional method, according to the conventional method, when the adjustment work of the end faces of the optical fiber cores is completed, the connection using the CCD camera and the TV monitor is completed. The image work must be done 10 times. That is, since the fiber whose angle has been adjusted first is used after the adjustment work is completed, there is often an angle shift, and it is usually necessary to repeat the angle adjustment work about three times.
For this reason, the image forming operation was very troublesome because it was very large (10 fibers) × (3 repetitions) = 30 times. On the other hand, according to the method of the present invention, no matter how many times the fiber angle adjustment work is repeated, only one imaging operation is required.
[0009]
That is, according to the method of the present invention, as shown in FIG. 3, the glass plate 15 is installed in front of the CCD camera 13, and the end surface 12 of the optical fiber core wire 11 is abutted against the glass plate 15. As a result, the end faces of the optical fiber core wires 11 are all uniformly aligned with the glass plate 15 surface. Further, since the gas plate 15 is transparent to visible light, it can be imaged by the CCD camera 13 and the end face 12 of the optical fiber can be confirmed by the TV monitor 14. Since the end face 12 of the optical fiber 11 when imaged by the CCD camera 13 is imaged simultaneously with all the core wires, it is not necessary to image each core wire, and the angle adjustment time can be greatly shortened. .
[0010]
As a material of the glass plate 15 used in the present invention, it is desirable to use quartz glass having a high ultraviolet transmittance. After the work of adjusting the angle of the end face of the optical fiber core, all the optical fiber cores are bonded and fixed with an adhesive such as an epoxy or acrylate UV curable adhesive, so if the ultraviolet transmittance of the glass plate is high, There is no need to remove the glass plate when the adhesive is cured. The fact that it is not necessary to remove the glass plate is important not only for improving the unit production efficiency but also for increasing the axial angle of the optical fiber.
[0011]
【The invention's effect】
According to the method of the present invention, a plurality of polarization maintaining optical fiber bundles having the same polarization maintaining axis can be manufactured in a short time and with high accuracy. Therefore, it is possible to easily match the extinction ratio of each optical fiber before bundling to the overall extinction ratio after bundling.
[Brief description of the drawings]
FIG. 1 is an end view of a polarization maintaining optical fiber. FIG. 2 is a partially omitted end view of a polarization maintaining optical fiber bundle. FIG. 3 is an illustration of a method of the present invention. Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Core 2 Stress imparting part 3 Clad part 4 Polarization maintaining axis 5 Polarization maintaining optical fiber 6 Polarizing maintaining optical fiber 7 Polarizing maintaining optical fiber bundle 11 Polarization maintaining optical fiber 12 End face 13 CCD camera 14 TV monitor 15 Glass plate

Claims (2)

A glass plate in which the end faces of the polarization maintaining optical fibers are bundled by aligning the angles of the polarization maintaining axes of the plurality of polarization maintaining optical fibers subjected to the end face cut , and transparent to the visible light. A method for manufacturing a polarization maintaining optical fiber bundle, wherein the optical fiber end faces are aligned with each other and the optical fibers are bonded and fixed together with an adhesive. 2. The method of manufacturing a polarization-maintaining optical fiber bundle according to claim 1, wherein the glass plate is quartz glass having a high ultraviolet transmittance, and an ultraviolet curable adhesive is used as an adhesive, and the glass plate is cured with ultraviolet rays. .

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