JPS6141108A - Method and device for manufacturing optical fiber branching part - Google Patents

Abstract

PURPOSE:To give a branching function to existing optical fibers and to form an economical branching part by heating said fibers to unite to one body, extending it and then making its outer periphery coincide with the outer periphery of a punch fiber. CONSTITUTION:A coating part of an existing 5-core tape core line 8, on which a branching part is to be formed, is removed, and said core line is arranged at array parts 9 so as to form a figure similar to a flat punch fiber to be connected to said core line, and is fixed to fixing parts 10. A voltage is impressed to a discharging part 11 in this state to make fibers in the heated and molten state, and simultaneously, a movable part 12 to which the array parts 9 and fixing parts 10 are fitted is pulled to extend the optical fiber so that its outer periphery will coincide with the outer periphery of the punch fiber to be connected. After that, the specified connection is carried out. Since the branching function is given to the existing optical fibers in this manner, a separate branching circuit is not necessary, thereby forming a practical and economical branching part.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention is an optical line using bunch fibers, in which a plurality of optical signals propagating through each core of the bunch fibers are extracted to a plurality of optical fibers, and a plurality of The present invention relates to a method and apparatus for manufacturing an optical fiber branch for propagating individual optical signals propagating through an optical fiber to each core of a bunch fiber.

(Conventional technology) Bunch fibers consist of a plurality of claddings that are fused and integrated, and have uniform grooves along the longitudinal direction of the outer periphery.This makes them less distinguishable than conventional multi-core fibers. Excellent. Furthermore, since the density is higher than that of current fibers, it is possible to manufacture optical cables at low cost by using bunch fibers.

Figures 6 and 7 show cross sections of typical bunch fibers.
As shown in the figure. FIG. 6 shows a flat bunch fiber in which each core 1 is arranged in a rectangular shape. FIG. 7 shows a star-shaped punch 7-eyeper in which each core 1 is arranged in a circle. The diameter of the cladding 2 surrounding one core 1 in a bunch fiber is usually 60 to 9
The cladding diameter of current optical fibers is between 0 μm and 11 μm.
The diameter is smaller than 15 μm, and each of these claddings is arranged in high density, so in optical lines using bunch fibers as subscriber line cables, it is difficult to use optical fibers with different cladding diameters and core diameters. The biggest problem is how to branch out. Under these circumstances, branching methods using small-diameter optical fibers, lens systems, planar optical waveguides, etc. have been proposed. The main conditions required for the branch section include ease of manufacture, ease of handling, and low insertion loss, but the conventional branching methods do not fully satisfy these points.

FIG. 8 shows an example of branching when a narrow-diameter 7-eyeper is used.

In the method shown in FIG. 8, a thin optical fiber 4 having the same diameter as the cladding surrounding one core of the bunch fiber 8 is used. When used as a branching optical fiber, various improvements are required, such as an increase in microbending loss, which is an essential problem with small-diameter optical fibers.

In the branching using the cell 7 lens 5 in FIG. 9, it is difficult to accurately correspond to the positional relationship between each core of the bunch fiber 8 and the light 7 eye <6 located at the other end via the selfoc lens 6. Considerable difficulties are expected in the field work.

An example of branching when using a planar guided waveguide is shown in the first ([1).
Many issues remain to be considered, such as how to fix the optical waveguide and the planar optical waveguide 7.

(Problems to be Solved by the Invention) As in the above-mentioned branching example, there is a common problem of whether a large number of optical fibers can accurately correspond to each other through a branching part in a bunch fiber having a plurality of cores. be.

(Means for Solving the Problems) In the present invention, in order to solve the above-mentioned problems, a special branching section is not required, and a part of the currently used optical fiber is provided with a branching function. The present invention will be explained in detail below with reference to the drawings.

FIG. 2 shows an embodiment of a branch manufactured by the method according to the invention, where 6 is an optical fiber. The basic principle of conventional branching methods is to insert a new branch between a bunch fiber and an individual optical fiber. On the other hand, this method is characterized in that the existing optical fiber 6 has a function as a branch, so that the new fiber 6 is
No circuit required.

The basic principle of this method is to arrange multiple optical fibers in a similar shape to the array of each core in a bunch fiber, draw them at the same time as external heating, and draw multiple optical fibers with the same cross section as the bunch fiber. It is formed within the cross section of the optical fiber bundle. By externally heating and drawing, a plurality of optical fiber bundles are inevitably fused and integrated, and high efficiency can be expected at the time of splicing. Possible heat sources for external heating include electric furnaces, high-power lasers, electric discharges, etc.
Among these, heating by electric discharge is the most suitable considering portability 1 handling during on-site work etc. 0 heating 11
! The aWk optical fiber bundle that has been f-quenched becomes tapered as shown in FIG. 9 around the heated part. By cutting at , it is possible to provide a plurality of optical fiber bundles with a sufficient function as a branching section.

FIG. 1 shows an embodiment of a branch manufacturing apparatus according to the present invention. FIG. 1 shows the case where a branch part for a flat bunch fiber is manufactured using a six-fiber tape core 5I8. In this method, it is first necessary to remove the covering portion of the six-fiber ribbon. Reference numeral 9 denotes an optical fiber array section in which optical fibers from which coating portions have been removed are arranged so as to be similar to the array of cores in the cross section of the bunch fiber. In the case of flat bunch fibers, multiple optical fibers are densely arranged on one plane.
A similar arrangement of optical fibers with each core in a bunch fiber is possible. IO is a (branch) running part for fixing a plurality of lights 7/aiba. Reference numeral 11 is a discharge section for melting the optical fiber. In this case, in order to form a discharge path uniformly in the longitudinal direction of the optical fiber, it is also effective to use a discharge section consisting of multiple electrodes. 12 is a movable part for drawing the optical fiber in a molten state.

In this embodiment, the tape core wires arranged in a similar shape to each core of the bunch fiber are brought into a molten state by electric discharge. By moving the fixed part and the movable part including the array part in synchronization with the discharge so as to apply a tensile force to the optical fiber, it is possible to form a branched part that is melted and integrated.

FIG. 8 shows a branching section for a flat bunch fiber produced by the branching section manufacturing apparatus shown in FIG. 1, where 6 is an optical fiber and 18 is a coating. Each optical fiber 6 in the tape core has only a line contact portion in the longitudinal direction of the optical fiber, and the outer periphery of the fused and integrated branch portion has an uneven portion similar to that of a bunch fiber. . Therefore, even after being fused and integrated, each core has an axis alignment standard that corresponds to the core, and the identification is good. Figure 4 shows an example of a limb manufacturing device by Mizumoto and Akira. show. FIG. 4 shows the case where a branch part for a star-shaped bunch fiber is manufactured using a five-core round optical fiber core $14. Fourth
In the figure, 9 is an optical fiber arrangement section, 10 is an optical fiber fixing section, 11 is a discharge section, and 12 is a movable section. In this method, the reference numeral 9 is composed of a hollow pipe, and the optical fibers in the round optical fiber cores are densely arranged in the hollow pipe so as to be similar to the arrangement of the cores of the bunch fibers.

FIG. 6 shows a branch section for round bunch fibers produced by the limb manufacturing apparatus in FIG. 4, and 6 is an optical fiber;
18 is a coating.

As an example, the core wires in which a plurality of optical fibers shown in FIG. 8 and FIG. It is also effective for multiple optical fibers.

(Effects of the Invention) As explained above, the optical fiber having the branching 5411 function according to the present invention does not particularly require or require a separate branching circuit, so it is highly practical and extremely economical. be. Since separate branch circuits are not required, there is only one connection point between the bunch fibers and the individual fibers to be connected, resulting in a low-loss branch circuit configuration.

[Brief explanation of the drawing]

Fig. 1 is a diagram of an embodiment of an apparatus for manufacturing a branch part for flat bunch fibers, Fig. 2 is a diagram of an embodiment of an optical fiber branch part manufactured according to the present invention, and Fig. 8 is a diagram of an embodiment of a branch part for flat bunch fibers. Embodiment diagrams, FIG. 4 is an embodiment diagram of an apparatus for manufacturing a branch part for a house-shaped bunch fiber, FIG. 6 is an embodiment diagram of a branch part for a star-shaped bunch fiber, FIG. 6 is a sectional view of a flat bunch fiber, Figure 7 is a cross-sectional view of a star-shaped bunch fiber, Figure 8 is a branch contingency using a small-diameter 7-eyeper, Figure 9 is a limb contingency using a self-off lens, and Figure 1θ is a planar light guide. FIG. 3 is an example diagram of a branching circuit using a wave path. 1... Core 2... Clad 8...
Flat bunch fiber group...Small diameter optical fiber 6...
SELFOC lens 6...Hikari Fudeiva? ... Planar optical waveguide 8 ... Five-core tape core 9 ... Optical fiber arrangement section 10 ... Optical fiber fixing section 11 ... Discharge section 12 ... Movable section 18 ... Coating
14... Round optical fiber coated wire patent applicant
Nippon Telegraph and Telephone Public Corporation Figure 2 Figure 1 Figure 3 Figure 4 Figure 5 Figure 6

Claims (1)

[Claims] 1. A plurality of optical fibers are arranged in a similar shape to the arrangement of each core in a cross section of a bunch fiber to be connected, and a part of the arranged plurality of optical fiber bundles is heated by electric discharge heating. 1. A method for manufacturing an optical fiber branch section, which comprises simultaneously fusion-bonding and unifying the fusion-bonding section and stretching the fusion-bonding section so that the outer periphery of the fusion-bonding section coincides with the outer periphery of a bunch fiber. 2. An optical fiber array section for arranging a plurality of optical fibers in a shape similar to the arrangement of each core in the bunch fiber cross section, a discharge section for fusing and integrating the arranged plurality of optical fibers, and a plurality of Manufacture of an optical fiber branch comprising optical fiber fixing parts located on both sides of a discharge path for fixing the optical fiber, the fixing part having a mechanism movable in the longitudinal direction of the fixed optical fiber. Device.