JPH02187708A - Optical fiber coupler - Google Patents

Abstract

PURPOSE:To extremely facilitate a fusion stretching operation and to improve yield by removing the coatings of two coated tape optical fibers and fusion stretching the parts of these two fibers where the coatings are removed, thereby exactly paralleling the optical fibers. CONSTITUTION:The coatings 4 of the coated tape optical fibers for optical communication are partly removed to a prescribed length to form the parts where the coatings are removed to expose the two optical fibers. The parts where the coatings are removed are brought into contact with each other and the contact parts are heated by a high-temp. heat source, such as oxyhydrogen flame, and are thereby fused; further, these parts are stretched to form the fusion stretched part, by which the optical fiber coupler 1 is formed. The previous exact paralleling of the two optical fibers at the time of the fusion stretching is, therefore, easy and the fusion stretching operation is extremely easily carried out.

Description

[Detailed Description of the Invention] "Industrial Application Field" This invention relates to an optical fiber in an optical fiber ribbon,
An optical fiber coupler used when branching or combining light with another optical fiber of the same optical fiber tape, another optical fiber single core, or another optical fiber tape. It is related to.

``Prior Art'' Traditionally, as one of the optical fiber couplers used for coupling or branching optical signals, fusion splicing is a method in which a portion of multiple optical fibers is fused and stretched to form a fusion-stretched part. Stretched optical fiber couplers are known. To manufacture this fused and stretched type optical fiber coupler, first, a part of the coating of a single optical fiber or a bare optical fiber is removed to form a removed portion where the bare optical fiber is exposed, and then the coating is removed. It is produced by arranging a plurality of optical fibers with removed portions in parallel, heat-sealing a portion of the optical fibers exposed from the coat-removed portions, and further stretching to form a fused and stretched portion.

``Problem to be Solved by the Invention'' However, in the optical fiber coupler as described above, it is necessary to align each coat removal part extremely accurately and perform fusing and stretching. When producing an optical fiber coupler by fusion-drawing two single-core optical fibers, the two single-core optical fibers are placed in parallel and the part where the coating is removed and its vicinity are removed using a precision jig. The fibers were fixed and each end fiber +1' was fixed so that the core wires did not rub each other, and fusion and drawing was performed. There were problems in that the workability was poor, the work required a lot of skill, and the yield of high-performance optical fiber couplers was low.

In addition, the remaining optical fiber length portions (lead portions) of two optical fibers on each side of the optical fiber coupler fabricated in this way are separated from each other, which causes trouble when processing the excess length. was there.

The present invention has been made in view of the above circumstances, and has the following objects: (1) to provide an optical fiber coupler that can easily carry out the fusion-stretching operation and can smoothly process the excess length of the lead portion. There is.

[Means for Solving the Problems] - [As a means of achieving one object, in the present invention, a plurality of optical fibers are bundled into a tape, and the coating of the optical fiber tape is removed and exposed. The destination fiber and any other optical fiber of the same optical fiber tape, or an optical fiber of the removed portion of another single optical fiber, or an optical fiber of the removed portion of another optical fiber tape. The optical fiber was fused and stretched to form a fused and stretched portion to construct an optical fiber.

[Function-1 Light of optical fiber tape core] The fiber and the other end fiber of the same optical fiber tape core or the optical fiber of the coated part of another optical fiber single core wire or another optical fiber tape core Since the fused and drawn portion is formed by fusion-drawing one of the optical fibers in the portion where the coating is removed, it is extremely difficult to align the plurality of optical fibers accurately in advance during the fusion-drawing operation. It becomes easier. In addition, the excess length of the optical fiber coupler is collected into one fiber, allowing smooth processing of the excess length. Further, since a plurality of sets of end fiber couplers can be produced by fusion-stretching the optical fibers in the optical fiber ribbon, it is possible to increase the density of the optical fiber coupler.

Embodiment FIG. 1 is a diagram showing a first embodiment of the present invention, and reference numeral 1 in the figure represents an optical fiber coupler.

This optical fiber coupler 1 removes a part of the coating 4 of an optical fiber tape core 3 made by bundling two optical fibers 2 into a tape shape, and fuses and stretches the exposed part of the optical fiber 2. The fused and stretched portion 5 is formed by holding the fused and stretched portion 5 together.

”-The fiber toe 2 is commonly used for optical communications;
Various optical fibers can be used, such as a silica-based non-glue mode optical fiber, a graded-index optical fiber, or a stress-applied polarization-maintaining optical fiber.

In the fusion-stretching section 5, the cores of the two optical fibers 2 in the optical fiber tape core 3 are brought close to each other, allowing optical coupling between the respective optical fibers 2. That is,
The fusion/stretching section 5 is configured to branch incident light such that an optical signal propagating within one optical fiber 2 is branched to the other optical fiber 2, or to couple a plurality of incident lights.

” - Fabricate the optical fiber coupler l with the following configuration as follows. First, a predetermined length of a portion of the coating 4 of the optical fiber ribbon 3 is removed to form a removed portion where two optical fibers 2 are exposed, as shown in FIG. Then,
Both ends of the two exposed fibers 2 are bundled and fixed, and a portion of the two optical fibers 2 are brought into contact. Next,
The portion where the two optical fibers 2 are brought into contact is heated with a high-temperature heating source such as an oxygen-hydrogen flame to be fused and then further stretched to form a fused and stretched portion 5. Through the following operations, the optical fiber coupler 1 shown in FIG. 1 is manufactured. Note that the fused and stretched portion 5 of the fiber coupler I produced in this way is as follows:
Reinforce it with synthetic resin if necessary.

This optical fiber coupler 1 is constructed by fusion-stretching two optical fibers 2 of an optical fiber tape core 3 to form a fusion-stretching section 5. It becomes extremely easy to align the optical fibers 2 accurately.

Further, the extra length of the optical fiber coupler 1 is collected into one fiber, and the extra length can be processed smoothly.

FIG. 3 is a diagram showing a second embodiment of the present invention, and reference numeral 6 in the figure represents an optical fiber coupler. The optical fiber coupler 6 according to this example is constructed by removing a part of the coating 8 of an optical fiber tape core 7 formed by bundling ten optical fibers 2 into a tape, and combining the exposed ten optical fibers 2 into two. There are five sets of optical fibers in each set, and the two optical fibers of each set are fused and stretched to form a fused and stretched section 5. This optical fiber coupler 6 connects 10 of the optical fiber tape cores 7.
The book optical fibers 2 are made into 5 sets of 2, and each set is 2×
Since it can act as a two-cedar coupler and five couplers can be made in the optical fiber tape core 6, it is possible to increase the density of the optical fiber couplers.

In addition, in this example, an example is shown in which five pairs of couplers are formed using the optical fiber ribbon 7 which is a bundle of ten optical fibers 2, but the number of optical fibers in the optical fiber ribbon is two. There is no particular limitation as long as it is above, and 1
A fusion-stretched portion may be formed by fusion-stretching three or more optical fibers using one coupler.

FIG. 4 is a diagram showing a third embodiment of the present invention, and reference numeral 9 in the figure represents an optical fiber coupler. This optical fiber coupler 9 connects the coating 11 of the optical fiber tape core wire IO, which is made by bundling four optical fibers 2 into a tape, to the four optical fibers 2.
Two of the optical fibers are removed so as to be partially exposed, and the exposed two optical fibers 2 are fused and stretched to form a fused and stretched portion 5. Two optical fibers 2 of each optical fiber tape core 1O become lead portions (extra length portions) of the coupler, and the other two are used as normal optical communication fibers.

The optical fiber coupler 9 of this example has the same effect as the optical fiber coupler l of the first embodiment, and also has an optical fiber 2 other than the one used as a coupler in the optical fiber ribbon IO. Therefore, optical fiber coupler and optical communication can be performed using the same optical fiber ribbon.

FIG. 5 is a diagram showing a fourth embodiment of the present invention, and reference numeral 12 in the figure is an optical fiber coupler. This optical fiber coupler 12 connects a coating 11 of an optical fiber ribbon 10, which is a tape-like bundle of four optical fibers 2, to one of the outermost optical fibers 2 among the four optical fibers 2. One optical fiber 2 exposed from the removed portion is fused to a tip fiber 15 exposed by removing a portion of the coating 14 of another single optical fiber 13. Stretched u
It is configured by tightening it to form a fused and stretched portion 5. The remaining three optical fibers 2 of this optical fiber ribbon 10 are used as normal optical communication fibers.

The optical fiber coupler 12 of this example provides substantially the same effect as the optical fiber coupler 9 of the third embodiment.

FIG. 6 is a diagram showing a fifth embodiment of the present invention, and reference numeral 16 in the figure is an optical fiber coupler. This optical fiber coupler 16 includes a coating 1 of a four-core optical fiber ribbon IO.
1 to expose a part of the outermost one of the four optical fibers 2. 1; The exposed optical fibers 2 of the two optical fiber tape cores 10a and 1Ob that have been removed are fused and stretched to form a fused and stretched portion 5.

In this optical fiber coupler I6, one optical fiber 2 of each of the two optical fiber tapes toa and Job becomes the extra length of the coupler, and each optical fiber tape cable 10a,
It is possible to perform optical coupling or branching between the optical fibers 2 and 10b, and also to perform normal optical communication using another optical fiber 2. This provides the following effects.

Light from an optical fiber in an optical fiber tape core and another optical fiber in the same optical fiber tape core or an optical fiber in a removed portion of a single optical fiber wire or a removed portion of another optical fiber tape core wire. Since the fused and drawn portion is formed by fusion-drawing any one of the optical fibers of the fiber, it is extremely easy to align multiple optical fibers accurately in advance during the fusion-drawing operation, resulting in high performance. Optical fiber couplers can be used to increase yield. In addition, the extra length of the optical fiber coupler is combined into one fiber, making it possible to process the extra length smoothly.

Since it is possible to fabricate a plurality of sets of optical fiber couplers by fusion-stretching the optical fibers in the optical fiber tape, it is possible to increase the density of the optical fiber couplers.

[Brief explanation of the drawing]

FIG. 1 is a plan view of an optical fiber coupler showing a first embodiment of the present invention, and FIG. 2 is a diagram for explaining a method of manufacturing the optical fiber coupler shown in FIG. FIG. 3 is a plan view of an optical fiber coupler showing a second embodiment of the present invention, and FIG. 4 is a plan view of an optical fiber coupler showing a third embodiment of the present invention. FIG. 5 is a plan view of an optical fiber coupler showing a fourth embodiment of the invention, and FIG. 6 is a plan view of an optical fiber coupler showing a fifth embodiment of the invention. 5...Fused and stretched portion. 3...Optical fiber center line

Claims (1)

[Claims] Removal of the coating from an optical fiber tape that bundles multiple optical fibers into a tape to expose the exposed optical fibers, as well as removal of the coating from other optical fibers of the same optical fiber tape or another single optical fiber. An optical fiber coupler characterized in that the optical fiber of the section or the optical fiber of the coated removed section of another optical fiber tape core is fused and stretched to form a fused and stretched section. .