JPH0782163B2 - Fiber optic polarizer bobbin - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical fiber bobbin used as a polarizer of an optical system.

[0002]

2. Description of the Related Art A polarizer is an element that is inserted into an optical circuit of optical communication or various measuring instruments to select linearly polarized light from natural light, circularly polarized light and elliptically polarized light. It is one of the essential optical circuit elements. 1
There is one that passes only polarized light in one direction and the other that separates X and Y polarized waves in two directions orthogonal to each other.

As such a conventional polarizer, a polarizer composed of a compound polarized light prism using a crystal such as calcite or quartz having birefringence is generally used.

By the way, a general optical fiber is easily affected by the disturbance of the polarization state due to a weak disturbance, and a polarization-maintaining optical fiber has been developed for propagating while maintaining the phase information and polarization state of light stably. In an all-optical fiber gyro using an optical fiber, all optical circuit elements such as a polarizer, a phase modulator, and a directional coupler are configured by the polarization-maintaining optical fiber.

The optical fiber polarizer in the above-mentioned optical circuit element has an optical fiber wound around a resin bobbin with a diameter of 30 mm, for example, and a bending stress is applied to the optical fiber so that X,
It is configured to take out only the X polarization of the Y polarization.
The optical fiber is fixed to the bobbin with an adhesive.

[0006]

However, in such a conventional optical fiber polarizer bobbin, when tension is applied excessively when the optical fiber is wound, the loss of the light amount increases. Further, the tension changes due to the thermal expansion of the resin bobbin or the creep of the resin bobbin and the optical fiber sheath, and the polarization characteristics also change accordingly.

Further, as a problem at the time of manufacture, it takes a curing time because the optical fiber is fixed with an adhesive, or the bobbin is made by injection-molding resin, but the body part is deformed due to molding shrinkage, and the aligned winding cannot be performed. There's a problem.

In the present invention, in consideration of various problems of the conventional optical fiber polarizer bobbin described above, the conventional bobbin is simply processed to prevent the polarization performance from deteriorating, and the optical fiber polarization is easy to manufacture. The challenge is to provide child bobbins.

[0009]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention has a cylindrical body having a predetermined diameter around which an optical fiber is wound, and has a collar at both ends thereof. The optical fiber polarizer bobbin has a small hole penetrating from the brim to the brim so as to bulge.

It is preferable to provide a notch for attaching the temporary fixing tape to a part of the collar of the bobbin.

[0011]

Since the polarizer bobbin of the present invention is constructed as described above, when the optical fiber is wound to manufacture the polarizer, the pin is inserted into the small hole to wind the optical fiber, and the optical fiber is fixed. When the rear pin is pulled out, the tension of the optical fiber becomes free and the extra tension does not act at all. Therefore, even if there is thermal expansion of the bobbin, the characteristics of the polarizer do not change, and a stable action can be obtained.

[0012]

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

FIG. 1 shows an optical fiber polarizer bobbin 1 of the embodiment.
3 is an external perspective view of FIG. As shown, the bobbin 1 is composed of a columnar body 2 having collars 3 at both ends. Bobbin 1
A small hole 4 penetrates from the brim to the brim and is provided in parallel with the central axis of the cylindrical body 2. A cylindrical pin 5 shown in the figure is inserted into the small hole 4 until a process in the middle of manufacturing the polarizer. Also, a part of the collar 3 is provided with a notch 6 for attaching the temporary fixing tape. In addition, the bobbin 1 of the embodiment
Is a resin having a cylindrical body 2 with a diameter of 30 mm and a collar diameter of 33 mm.

An optical fiber polarizer is produced by winding one layer of the optical fiber a around the bobbin 1 having the above-mentioned structure.

As shown in FIG. 2A, the optical fiber a
The pin 5 is inserted into the bobbin 1 in advance before winding. From above, the optical fiber a is wound within a predetermined tension by a winding machine (not shown). After the winding is completed, the optical fiber a is fixed by the fixing method described below, and then the pin 5 is pulled out. Then, the tension of the optical fiber becomes free, and only bending is applied. Therefore, excessive tension is prevented, and the tension of the optical fiber does not change even if the diameter changes due to thermal expansion of the bobbin 1. Therefore, the characteristics of the polarizer are stable.

After the winding is completed, as shown in (b), the temporary fixing tape b is attached at the position of the notch 6 of the collar 3 to temporarily fix the optical fiber a. In this state, the bobbin 1 is removed from the winding machine, and an adhesive is applied around the optical fiber a and cured to fix the same.

The cylindrical body 2 of the bobbin 1 is formed so that its cross section is slightly tapered as shown in FIG. By providing this taper, it is possible to prevent the cross section from becoming arcuate due to contraction when the bobbin 1 is molded by injection molding, and it is possible to prevent deviation when the optical fiber a is wound.

[0018]

As described in detail above, the optical fiber polarizer bobbin of the present invention is provided with a small hole penetrating from the brim to the brim and the optical fiber is wound around the bobbin and fixed while the pin is inserted into the small hole. The tension of the optical fiber is set to be free when the rear pin is pulled out, so that the tension of the optical fiber is not applied to the optical fiber, and the stress variation to the optical fiber due to thermal expansion and creep is prevented and stable polarizer characteristics are maintained. Is obtained. Further, if a notch is provided in a part of the brim, a tape can be easily attached and temporarily fixed at the time of production, and an advantage that a polarizer with high accuracy can be produced can be obtained.

[Brief description of drawings]

FIG. 1 is an external perspective view of a polarizer bobbin of an example.

FIG. 2 is a diagram illustrating a method of manufacturing a polarizer bobbin.

[Explanation of symbols]

 1 Optical Fiber Polarizer Bobbin 2 Cylindrical Body 3 Collar 4 Small Hole 5 Pin 6 Notch a Optical Fiber b Temporary Fixing Tape

Claims (2)

[Claims] 1. A small-diameter cylindrical body around which an optical fiber is wound has collars at both ends, and when a columnar pin is inserted, a small hole is passed through the collar to the collar so that a part of the winding body surface swells. An optical fiber polarizer bobbin provided. 2. The optical fiber polarizer bobbin according to claim 1, wherein a notch for attaching the temporary fixing tape is provided in a part of the collar of the bobbin.