JPH11231231A - Optical fiber non-reflection terminator and production thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate the production of a non-reflection terminator and to shorten production time by holding an optical fiber inserted through the inserting hole of a pipe while bending it into prescribed shape through the modification of the pipe. SOLUTION: This non-reflection terminator is composed of an optical fiber 1 and a pipe 2 having the inserting hole for inserting the optical fiber 1. The pipe 2 is formed from a shape memory alloy and made almost cylindrical before modification. By performing heat treatment due to hot water or hot air, this pipe 2 is bent in lengthwise direction and modified into coil shape. At such a time, the inserting hole is deformed from the state through the lengthwise direction of the pipe 2 to the state bent into coil shape as well. Then, the optical fiber 1 is inserted through the inserting hole of the pipe 2 and held by the modified pipe 2 while being bent into coil shape.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical fiber non-reflection terminator used in optical communication and optical coherent measurement technical fields, and a method of manufacturing the same.

[0002]

2. Description of the Related Art An optical fiber non-reflection terminator is for attenuating return light generated at the end of an optical fiber. For example, as shown below, a plurality of semiconductor laser light sources (hereinafter, referred to as LD light sources) are used. It is used, for example, when the light emitted from the optical coupler is multiplexed by an optical coupler.

FIG. 5 is a diagram showing an embodiment of an optical fiber anti-reflection terminator. In FIG. 5, reference numeral 7 denotes a wavelength of 1.31.
μm LD light source, 8 is a 1.55 μm wavelength LD light source, 9
Is an optical coupler, 10 is an optical fiber anti-reflection terminator, and 7a is L
The outgoing light from the D light source 7, 8a is the outgoing light from the LD light source 8, and 11a and 11b are the combined lights. LD light source 7, 8
Are split by the optical coupler 9 into multiplexed lights 11a and 11b. In this case, the combined light 11a
Are used as propagating light, and the combined light 11b becomes unnecessary light. Here, when the multiplexed light 11b, which is unnecessary light, is reflected at the end of the optical coupler 9, the reflected light re-enters the LD light sources 7, 8 and causes a decrease in the stability of the LD light sources 7, 8. Therefore, an optical fiber non-reflection terminator 10 is required at the end of the optical coupler 9.

FIG. 6 is a configuration diagram showing an example of a conventional optical fiber non-reflection terminator. In FIG. 6, reference numeral 1 denotes an optical fiber, and a ferrule 5 is attached to the optical fiber 1. Then, by polishing the end 1b of the optical fiber 1 obliquely, Fresnel reflection generated at the end 1b is escaped so as not to return to the optical fiber 1.

FIG. 7 is a configuration diagram showing an example of a conventional optical fiber non-reflection terminator. As shown in FIG. 7, the optical fiber 1 is fixed by an adhesive or the like while being wound around an aluminum rod 6. The optical fiber 1 fixed in such a state causes a loss due to bending, and the optical fiber 1
The amount of Fresnel reflection generated at the end 1b of the light source is attenuated.

[0006]

However, in the optical fiber anti-reflection terminator shown in FIG.
Furthermore, it took a very long time to perform the oblique polishing work of the terminal end 1b and its manufacture. Also, in the optical fiber non-reflection terminator shown in FIG. 6, it takes a very long time to wind the optical fiber 1 around the aluminum rod 6 and to bond and fix the optical fiber 1 after winding.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is easy to manufacture the optical fiber non-reflection terminator capable of shortening the manufacturing time, and the manufacturing thereof. The aim is to provide a method.

[0008]

In order to solve the above-mentioned problems, an optical fiber non-reflection terminator according to the first aspect of the present invention comprises:
An optical fiber, having a through hole through which the optical fiber is inserted, and a pipe made of a shape memory alloy that can be transformed into a predetermined shape by heating, wherein the optical fiber inserted through the through hole is a transformation of the pipe. Thus, it is configured to be held in a state of being bent into the predetermined shape.

According to the first aspect of the present invention, the optical fiber inserted through the insertion hole of the pipe is held in a state of being bent into the predetermined shape by the transformation of the pipe. The return light due to Fresnel reflection generated at the end of the optical fiber can be attenuated by the bending loss. Then, after the optical fiber is inserted through the insertion hole of the pipe, it is possible to transform the pipe made of the shape memory alloy into a predetermined shape by heating, so that it is easy to insert the optical fiber into the insertion hole. At the same time, it becomes easy to deform the optical fiber inserted into the insertion hole into a predetermined shape. Therefore, the manufacturing time of the optical fiber non-reflection terminator can be reduced as compared with the related art.

[0010] Specifically, the predetermined shape is, for example, a coil shape, a curved shape such as a wave shape, or a combination thereof.

According to a second aspect of the present invention, there is provided the optical fiber non-reflection terminator according to the first aspect, wherein the pipe can be transformed into a coil shape by heating.

According to the second aspect of the present invention, since the pipe can be transformed into a coil shape by heating, it is possible to bend the optical fiber into a coil shape and maintain the state.

According to a third aspect of the present invention, there is provided the optical fiber non-reflection terminator according to the first aspect, wherein the pipe can be transformed into a waveform by heating.

According to the third aspect of the present invention, since the pipe can be transformed into a waveform by heating, it is possible to bend the optical fiber into a waveform and maintain that state.

According to a fourth aspect of the present invention, there is provided an optical fiber non-reflection terminator, wherein an optical fiber, a shape memory alloy rod which can be transformed into a predetermined shape by heating, and an insertion hole for inserting the optical fiber and the shape memory alloy rod. Having a heat-shrinkable tube that shrinks by heating, wherein the optical fiber inserted through the insertion hole together with the shape-memory alloy rod is brought into close contact with the shape-memory alloy rod by contraction of the heat-shrinkable tube,
The shape memory alloy rod was held in a state of being bent into the predetermined shape by the transformation of the sticking shape memory alloy rod.

According to the fourth aspect of the present invention, the optical fiber having the insertion hole of the heat-shrinkable tube inserted together with the shape-memory alloy rod is brought into close contact with the shape-memory alloy rod by contraction of the heat-shrinkable tube, and the shape of the closely-fitted shape is Since the memory alloy rod is held in a bent state by the transformation, the return light due to Fresnel reflection generated at the end of the optical fiber can be attenuated due to the loss of the optical fiber bending. Then, after inserting the optical fiber together with the shape memory alloy rod into the insertion hole of the heat shrink tube, by heating,
Since it is possible to transform the shape memory alloy rod and shrink the heat-shrinkable tube, it is easy to insert the optical fiber and the shape memory alloy rod into the insertion hole of the heat-shrinkable tube, and to insert the heat-shrinkable tube. It is also easy to deform the optical fiber inserted into the hole into a predetermined shape. Therefore, the manufacturing time of the optical fiber non-reflection terminator can be reduced as compared with the related art.

Specifically, the predetermined shape is, for example, a coil shape, a curved shape such as a wave shape, or a combination thereof.

According to a fifth aspect of the present invention, there is provided the optical fiber non-reflection terminator according to the fourth aspect, wherein the shape memory alloy rod can be transformed into a coil shape by heating.

According to the fifth aspect of the present invention, since the shape memory alloy rod can be transformed into a coil shape by heating, it is possible to bend the optical fiber into a coil shape and maintain that state.

According to a sixth aspect of the present invention, there is provided the optical fiber non-reflection terminator according to the fourth aspect, wherein the shape memory alloy rod can be transformed into a waveform by heating.

According to the sixth aspect of the present invention, since the shape memory alloy rod can be transformed into a waveform by heating, the optical fiber can be bent into a waveform and maintained in that state.

According to a seventh aspect of the present invention, there is provided the method for manufacturing an optical fiber non-reflection terminator according to any one of the first to third aspects, wherein the optical fiber is inserted into an insertion hole of the pipe before transformation. Thereafter, the pipe is transformed by heating to deform the optical fiber into the predetermined shape.

According to the seventh aspect of the present invention, since the optical fiber is inserted into the insertion hole of the pipe before transformation and then the pipe is transformed by heating, the optical fiber can be inserted into the insertion hole. It is easy and it is easy to deform the optical fiber inserted into the insertion hole into a predetermined shape. Therefore, the manufacturing time of the optical fiber non-reflection terminator can be reduced as compared with the related art.

According to an eighth aspect of the present invention, there is provided the method for manufacturing an optical fiber non-reflection terminator according to any one of the fourth to sixth aspects, wherein the optical fiber is provided together with the shape memory alloy rod before transformation. After being inserted through the insertion hole of the heat-shrinkable tube before shrinking, the heat-shrinkable tube is shrunk by heating, and the optical fiber is brought into close contact with the shape-memory alloy rod, and the shape-memory alloy rod is removed. The optical fiber is transformed by heating to deform the optical fiber into the predetermined shape.

According to the eighth aspect of the invention, the optical fiber is inserted into the insertion hole of the heat-shrinkable tube before shrinkage together with the shape-memory alloy rod before transformation, and then the heat-shrinkable tube is shrunk by heating. The optical fiber is brought into close contact with the shape memory alloy rod, and the shape memory alloy rod is transformed by heating to deform the optical fiber into a predetermined shape. It is easy to insert the optical fiber through the insertion hole of the tube, and it is also easy to deform the optical fiber inserted into the insertion hole of the heat-shrinkable tube into a predetermined shape. Therefore,
The manufacturing time of the optical fiber non-reflection terminator can be reduced as compared with the related art.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to FIGS.

[First Embodiment] FIG. 1 is a diagram showing an optical fiber non-reflection terminator according to a first embodiment of the present invention.

As shown in FIG. 1, an optical fiber non-reflection terminator 10 of this embodiment comprises an optical fiber 1 and a pipe 2 having an insertion hole 2A through which the optical fiber 1 is inserted. The pipe 2 is formed of a shape memory alloy, and has a substantially cylindrical shape (state (a)) before transformation. By performing a heat treatment such as hot water or hot air, the pipe 2 is bent in its length direction and transformed into a coil shape (state (b)).
At this time, the insertion hole 2A also deforms from a state penetrating in the length direction of the pipe 2 to a state bent into a coil shape. The optical fiber 1 is inserted through the insertion hole 2A of the pipe 2 and is held by the transformed pipe 2 in a state of being bent into a coil shape.

When manufacturing the optical fiber non-reflection terminator 10, first, the optical fiber 1 is inserted into the insertion hole 2A of the pipe 2 before transformation (state (a)).
The pipe 2 is subjected to heat treatment such as hot water or hot air to transform the pipe 2 into a coil shape (state (b)). Then, the optical fiber 1 inserted through the insertion hole 2A becomes the insertion hole 2A.
At the same time, it is deformed into a coil shape and held in that state. Here, when the size of the coil formed by the optical fiber 1 is, for example, 5 turns or more at φ5 mm, the optical fiber 1 generates a loss due to bending of about 30 dB, and generates a loss of about 60 dB in reciprocation. I do. The Fresnel reflection generated at the end of the optical fiber 1 is reduced to 14
Considering dB, the optical fiber non-reflection terminator 10 of about 70 dB can be formed by this method.

The pipe 2 may be transformed into a wavy shape, for example, as shown below. FIG. 2 is a diagram showing a modification of the optical fiber non-reflection terminator of FIG. In FIG. 2, the optical fiber 1 inserted through the insertion hole 2A of the pipe 2 is deformed in a wave shape with the transformation of the pipe 2 by the heat treatment, and is held in that state ((b)).
State). The optical fiber 1 thus deformed in a wave shape
As in the case where the optical fiber 1 is deformed into a coil shape, return light due to Fresnel reflection generated at the end of the optical fiber 1 can be attenuated by bending loss.

As described above, according to the optical fiber non-reflection terminator 10 of the first embodiment, after the optical fiber 1 is inserted into the insertion hole of the pipe 2 before transformation, the pipe 2 is transformed by heat treatment. Thus, the optical fiber 1 can be easily inserted into the insertion hole 2A, and the optical fiber 1 inserted into the insertion hole 2A can be easily deformed into a coil shape or a waveform. Therefore, the manufacturing time of the optical fiber non-reflection terminator 10 can be reduced as compared with the related art.

The shape of the pipe 2 after transformation is not limited to the coil shape or the wave shape shown in the present embodiment, but the insertion hole 2A through which the optical fiber 1 is inserted is deformed into a bent state. Any shape may be used if possible.

[Second Embodiment] An optical fiber non-reflection terminator according to a second embodiment of the present invention will be described with reference to FIGS. In the second embodiment, the same parts as those in the above-described first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

FIG. 3 is a diagram showing an optical fiber non-reflection terminator according to a second embodiment of the present invention. As shown in FIG. 3, the optical fiber non-reflection terminator 20 of this embodiment includes an optical fiber 1, a shape memory alloy rod 3, and an insertion hole 4A through which the optical fiber 1 and the shape memory alloy rod 3 are inserted. And a heat-shrinkable tube 4. The shape memory alloy rod 3 can be transformed by heat treatment such as hot water or hot air. Before transformation, the shape memory alloy rod 3 becomes rod-shaped ((a) state), while after transformation, its length direction is bent. , Coil shape (state of (b)).
The heat-shrinkable tube 4 can be shrunk by heat treatment such as hot water or hot air. And the optical fiber 1
The insertion hole 4A of the heat-shrinkable tube 4 is inserted together with the shape-memory alloy rod 3 so that the heat-shrinkable tube 4 is in close contact with the shape-memory alloy rod 3 due to the shrinkage of the heat-shrinkable tube 4, and the transformation of the shape-memory alloy rod 3 is in close contact. Is held in a state of being bent into a coil shape.

In manufacturing the optical fiber anti-reflection terminator 20, first, the optical fiber 1 is inserted into the insertion hole 4 of the heat-shrinkable tube 4 before shrinkage together with the shape memory alloy rod 3 before transformation.
A (state (a)). Then, the heat-shrinkable tube 4 is shrunk by heat treatment such as hot water or hot air, and the shape memory alloy rod 3 is transformed into a coil shape (state (b)). Then, the optical fiber 1 inserted through the insertion hole 4 </ b> A adheres to the shape memory alloy rod 3 by the contraction of the heat shrinkable tube 4, and is held in a state of being bent into a coil shape by the transformation of the closely adhered shape memory alloy rod 3. It will be. The optical fiber 1 thus deformed into a coil shape can attenuate return light due to Fresnel reflection generated at the end of the optical fiber 1 due to bending loss, as in the first embodiment.

Further, the shape memory alloy rod 3 may be transformed into a wavy shape, for example, as shown below. FIG.
FIG. 4 is a diagram showing a modification of the optical fiber non-reflection terminator of FIG. 3. In FIG. 4, the optical fiber 1 inserted through the insertion hole 4A of the heat-shrinkable tube 4 before shrinkage together with the shape-memory alloy rod 3 before transformation causes the transformation of the shape-memory alloy rod 3 by heat treatment and shrinkage of the heat-shrinkable tube 4. At the same time, it is deformed into a wave shape and is held in that state (state (b)). The optical fiber 1 thus deformed in a wave shape can attenuate return light due to Fresnel reflection generated at the end of the optical fiber 1 due to bending loss, similarly to the case where the optical fiber 1 is deformed into a coil shape.

As described above, according to the optical fiber non-reflection terminator 20 of the second embodiment, the optical fiber 1 is transferred to the heat-shrinkable tube 4 before shrinkage together with the shape memory alloy rod 3 before transformation.
Then, the heat-shrinkable tube 4 is shrunk by heat treatment to bring the optical fiber 1 into close contact with the shape memory alloy rod 3, and the shape memory alloy rod 3 is transformed, Since the fiber 1 is deformed into a coil shape or a waveform, the optical fiber 1 and the shape memory alloy rod 3 can be easily inserted into the insertion hole 4A of the heat-shrinkable tube 4, and the insertion hole 4A of the heat-shrinkable tube 4 can be easily inserted. It is also easy to deform the optical fiber 1 inserted into the coil into a coil shape or a waveform. Therefore, the manufacturing time of the optical fiber non-reflection terminator 20 can be reduced as compared with the related art.

The shape of the shape memory alloy rod 3 after transformation is not limited to the coil shape or the wave shape shown in this embodiment, but may be any shape as long as it is bent. . In addition, in each of the above embodiments, the detailed structure and the like specifically shown can be appropriately changed without departing from the gist of the invention.

[0039]

According to the first aspect of the present invention, the optical fiber inserted through the insertion hole of the pipe is held in a state of being bent into the predetermined shape by the transformation of the pipe. The return light due to Fresnel reflection generated at the end of the optical fiber can be attenuated by the bending loss of the optical fiber. Then, after the optical fiber is inserted into the insertion hole of the pipe, it is possible to transform the pipe made of the shape memory alloy into a predetermined shape by heating, so that it is easy to insert the optical fiber into the insertion hole. At the same time, it becomes easy to deform the optical fiber inserted into the insertion hole into a predetermined shape. Therefore, the manufacturing time of the optical fiber non-reflection terminator can be reduced as compared with the related art.

According to the second aspect of the present invention, the pipe is
Since it can be transformed into a coil shape by heating, it becomes possible to bend the optical fiber into a coil shape and hold that state.

According to the third aspect of the present invention, the pipe is
Since it can be transformed into a waveform by heating, it is possible to bend the optical fiber into a waveform and maintain that state.

According to the fourth aspect of the present invention, the optical fiber in which the insertion hole of the heat-shrinkable tube is inserted together with the shape-memory alloy rod comes into close contact with the shape-memory alloy rod by the contraction of the heat-shrinkable tube, and the closely-fitted shape-memory alloy rod. Since the alloy rod is held in a bent state by the transformation, the return light due to the Fresnel reflection generated at the end of the optical fiber can be attenuated due to the loss of the optical fiber.
Then, after inserting the optical fiber into the insertion hole of the heat-shrinkable tube together with the shape-memory alloy rod, the shape-memory alloy rod can be transformed by heating, and the heat-shrinkable tube can be shrunk. It is easy to insert the memory alloy rod through the insertion hole of the heat-shrinkable tube, and it is also easy to deform the optical fiber inserted into the insertion hole of the heat-shrinkable tube into a predetermined shape. Therefore, the manufacturing time of the optical fiber non-reflection terminator can be reduced as compared with the related art.

According to the fifth aspect of the present invention, since the shape memory alloy rod can be transformed into a coil shape by heating,
It becomes possible to bend the optical fiber into a coil shape and hold that state.

According to the sixth aspect of the present invention, since the shape memory alloy rod can be transformed into a waveform by heating, it is possible to bend the optical fiber into a waveform and maintain that state.

According to the seventh aspect of the present invention, since the optical fiber is inserted into the insertion hole of the pipe before transformation and then the pipe is transformed by heating, it is easy to insert the optical fiber into the insertion hole. In addition, it becomes easy to deform the optical fiber inserted into the insertion hole into a predetermined shape. Therefore, the manufacturing time of the optical fiber non-reflection terminator can be reduced as compared with the related art.

According to the eighth aspect of the present invention, the optical fiber is inserted into the insertion hole of the heat-shrinkable tube before shrinkage together with the shape-memory alloy rod before transformation, and then the heat-shrinkable tube is shrunk by heating. Since the optical fiber is brought into close contact with the shape memory alloy rod and the shape memory alloy rod is transformed by heating to deform the optical fiber into a predetermined shape, the optical fiber and the shape memory alloy rod are heat-shrinkable. And the optical fiber inserted through the insertion hole of the heat-shrinkable tube can be easily deformed into a predetermined shape. Therefore, the manufacturing time of the optical fiber non-reflection terminator can be reduced as compared with the related art.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an optical fiber non-reflection terminator according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a modification of the optical fiber non-reflection terminator of FIG.

FIG. 3 is a diagram showing an optical fiber non-reflection terminator according to a second embodiment of the present invention.

FIG. 4 is a diagram showing a modified example of the optical fiber non-reflection terminator of FIG. 3;

FIG. 5 is a diagram showing an embodiment of an optical fiber anti-reflection terminator.

FIG. 6 is a configuration diagram showing an example of a conventional optical fiber non-reflection terminator.

FIG. 7 is a configuration diagram showing an example of a conventional optical fiber non-reflection terminator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Optical fiber 2 Pipe 2A insertion hole 3 Shape memory alloy rod 4 Heat shrinkable tube 4A insertion hole 10 Optical fiber non-reflection terminator 20 Optical fiber non-reflection termination

Claims (8)

[Claims] 1. An optical fiber, comprising: a pipe having an insertion hole through which the optical fiber is inserted, and a pipe made of a shape memory alloy which can be transformed into a predetermined shape by heating, wherein the optical fiber inserted through the insertion hole is The optical fiber non-reflection terminator, which is held in a state of being bent into the predetermined shape by the transformation of the pipe. 2. An optical fiber non-reflection terminator according to claim 1, wherein said pipe can be transformed into a coil shape by heating. 3. An optical fiber non-reflection terminator according to claim 1, wherein said pipe is capable of being transformed into a waveform by heating. 4. An optical fiber, a shape memory alloy rod capable of being transformed into a predetermined shape by heating, a heat shrinkable tube having an insertion hole through which the optical fiber and the shape memory alloy rod are inserted, and shrinking by heating. The optical fiber, which has been inserted through the insertion hole together with the shape memory alloy rod, is brought into close contact with the shape memory alloy rod by contraction of the heat-shrinkable tube, and is transformed into the predetermined shape by transformation of the closely adhered shape memory alloy rod. An optical fiber non-reflection terminator, which is held in a bent state. 5. The optical fiber non-reflection terminator according to claim 4, wherein said shape memory alloy rod can be transformed into a coil shape by heating. 6. An optical fiber non-reflection terminator according to claim 4, wherein said shape memory alloy rod can be transformed into a waveform by heating. 7. The method of manufacturing an optical fiber non-reflection terminator according to claim 1, wherein the pipe is inserted after the optical fiber is inserted into the pipe before transformation. A method for manufacturing an optical fiber non-reflection terminator, wherein the optical fiber is deformed into the predetermined shape by being transformed by heating. 8. The method for manufacturing an optical fiber non-reflection terminator according to claim 4, wherein the heat shrinkage of the optical fiber together with the shape memory alloy rod before transformation is performed before the shrinkage. After being inserted into the insertion hole of the tube, the heat-shrinkable tube is shrunk by heating to bring the optical fiber into close contact with the shape memory alloy rod, and the shape memory alloy rod is transformed by heating, A method of manufacturing an optical fiber non-reflection terminator, comprising: deforming the optical fiber into the predetermined shape.