JP2742830B2 - Optical fiber terminal fixing method - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for fixing an optical fiber terminal while maintaining the relative positions of a plurality of optical fibers.

[Prior Art] As a conventional method of fixing an optical fiber terminal of this type, for example, there is a method disclosed in Japanese Patent Application Laid-Open No. 1-300207.

According to this method, in a method for manufacturing an optical fiber array in which a plurality of optical fibers are arranged at predetermined positions, a silicon material is provided with a V-groove made of a crystal plane, and the silicon fiber is used to mold the optical fiber by the V-groove. It is characterized in that it is arranged at a predetermined position, and is manufactured by filling a molding material into a mold made of the silicon material and molding.

[Problems to be Solved by the Invention] However, in such a conventional method for fixing an end of an optical fiber, a structure is employed in which a plurality of optical fibers are fixed by a molding material. In addition, there is a problem that the dimensional stability after molding is poor due to molding shrinkage at the time of curing, and is easily affected by heat.

The present invention has been made in view of such a conventional problem, and fixes a plurality of optical fibers with a grooved jig having a plurality of aligned V-grooves. It is an object of the present invention to solve the above-mentioned problem by performing a batch and fixing a plurality of optical fiber terminals collectively.

Means for Solving the Problems In order to achieve the above object, a method for fixing an end of an optical fiber according to the present invention comprises exposing an optical fiber by stripping a coating of an end of a plurality of optical fiber cores, and exposing the optical fiber. After covering the exposed surface of the fiber with a metal coating, the optical fibers are respectively arranged and fixed in the respective V-grooves of the grooved jig having a plurality of aligned V-grooves. Is characterized by performing an electroforming process on the entire periphery of the optical fiber and fixing a plurality of optical fiber terminals collectively by an electroformed product.

[Operation] A plurality of optical fibers are arranged in each V-groove and fixed to a grooved jig. In this state, an optical fiber terminal is subjected to electroforming to maintain a predetermined interval between adjacent optical fibers. Thus, the terminals of the plurality of optical fibers can be fixed collectively by the electroformed product. In addition, since the electroformed product is a metal having a small coefficient of thermal expansion and does not cause molding shrinkage during curing unlike a molding material, a terminal fixing structure that has excellent dimensional stability and is not easily affected by heat. can get.

Example Next, an example of the present invention will be described with reference to the drawings.

1 to 4 show one embodiment of the present invention.
It is the figure applied to the tape type four core optical fiber.

In FIG. 1, reference numeral 1 denotes an optical fiber core, which comprises an optical fiber 2 composed of a core and a clad, and a coating material 3 coated on the optical fiber 2 in order to prevent strength deterioration or the like due to scratches. The coating material 3 generally has a two-layer structure of a plastic coating (primary coating) such as a silicone resin or an epoxy resin and a secondary coating (nylon resin or the like) for easy handling. It may have a three-layer structure in which a buffer layer is provided between the primary coating and the primary coating.
It may have a layered structure.

The coating material 3 at the terminal portion of the optical fiber core 1 is peeled to expose the optical fiber 2, and the entire surface of the optical fiber 2 and the end of the coating material 3 are covered with the conductive metal film 4. As a typical method, for example, various surface treatment methods such as electroless plating and vapor deposition can be applied.

The tips of the plurality of optical fibers 2 provided with the metal coating 4 are sandwiched and held by the grooved jig 5 to fix the relative positions of the adjacent optical fibers 2. The grooved jig 5 includes a V-block 7 having a plurality of aligned V-grooves 6, a holding plate 8 for holding the optical fiber 2 between the V-block 7, and a holding plate 8 for holding the holding plate 8 and the V-block 7. And a plurality of clips 9 to be held. The width, depth, angle, and interval of the V-grooves 6 are preliminarily manufactured to predetermined values with high precision, and the relative positions of the optical fibers 2 disposed in the respective V-grooves 6 are within the range of an allowable error. Set to.

Next, a plurality of optical fibers 2 are inserted into each V groove 6 of the V block 7.
2 and 3, a holding plate 8 is arranged on the V-groove 6 side to sandwich the optical fiber 2, and a clip 9 is hung on the V-block 7 and the holding plate 8 and held. I do. Then, an electrode 10 for plating is attached to the end of the coating material 3 of the optical fiber 1, and the electrode 10 is connected to the metal film 4.

Thereafter, as shown in FIG. 1, the lower part of the electrode 10 of the optical fiber core 1 is dipped together with the grooved jig 5 into a metal salt solution, and the other electrode 11 is inserted into the solution.
Electroforming is performed by electrolysis of the metal salt solution. Then, as shown in FIG. 4 and the like, the electroformed portion 12 is thickened so that the thickness of the electroformed portion 12 is substantially the same as the thickness of the coating material 3 so that there is no gap between the adjacent optical fibers 2. Thereby, the interval between the adjacent optical fibers 2 can be maintained with the same high precision as the highly accurate V-groove 6 previously set in the V block 7, and the relative position can be fixed with high precision. Various electroconductive metals such as nickel, chromium, and copper can be used as the electrodeposited metal.

Next, after taking out the optical fiber 1 from the metal salt solution and removing the electrode 10, the clip 9 is removed and the V-block 7 and the holding plate 8 are removed. Then, a portion (for example, surface A) of the electroformed portion 12 close to the grooved jig 5 is cut and polished. Thus, the relative positions of the four optical fibers 2 can be held and fixed at predetermined intervals, and the end faces of the optical fibers 2 can be processed with high accuracy.

In this case, an expensive grooved jig 5 having a V-groove 6 requiring high-precision machining can be used repeatedly many times. can get. In particular, fixing the end portion of the optical fiber by electroforming as in the present invention has the following advantages as compared with the case where a conventional plastic adhesive is used.

That is, since the coefficient of thermal expansion of the electroformed portion 12 is smaller than that of plastic (usually about 1/10) and there is no shrinkage during curing
The influence of heat on the terminal portion can be significantly reduced. In fixing the optical fiber, fixing means such as welding and soldering can be used.

The method for fixing an optical fiber terminal according to the present embodiment having the above-described functions and effects is particularly effective when used for a fiber array of an array module used for optical communication or an optical coupling section of a splitter module.

In the above embodiment, an example in which the present invention is applied to a tape type four-core optical fiber has been described. However, the present invention is not limited to this, and it is needless to say that the present invention can be applied to a tape type optical fiber having five or more cores. The present invention can be applied to other types of optical fibers other than the mold.

[Effects of the Invention] As described above, the present invention is configured as described above, and has the following effects.

A plurality of optical fibers are arranged in each V-groove and fixed to a grooved jig, and in this state, an electroforming process is performed on an optical fiber terminal, so that a relative position between adjacent optical fibers is maintained at a predetermined interval. Thus, the terminals of a plurality of optical fibers can be fixed collectively by electroforming. Therefore, a fiber array reproducing the dimensional accuracy of the V-groove of the grooved jig can be easily manufactured, and a highly accurate fiber end face can be obtained. Also,
Since the electroformed part is a metal with a small coefficient of thermal expansion and does not cause molding shrinkage during curing unlike molding materials, it has excellent dimensional stability and a terminal fixing structure that is not easily affected by heat. can get.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view showing one embodiment of the present invention, FIG. 2 is a partially sectional side view showing a terminal fixing structure according to the present invention, FIG. 3 is a front view thereof, and FIG. FIG. 4 is a sectional view taken along line IV-IV of FIG. 2. 1: optical fiber core wire, 2: optical fiber 3: coating material, 4: metal coating 5: grooved jig, 6: V groove 7: V block, 8: holding plate 9: clip, 10, 11: electrode 12 : Electroformed part

Claims (1)

(57) [Claims] An optical fiber is exposed by stripping the coating of the ends of a plurality of optical fiber cores, exposing the exposed surface of the optical fiber with a metal film, and then forming a groove having a plurality of aligned V grooves. The optical fibers are arranged and fixed in the respective V-grooves of the jig, and thereafter, the entire periphery of the metal film of the optical fiber is subjected to electroforming, and the terminals of the plurality of optical fibers are collectively formed by the electroformed product. A method of fixing an optical fiber terminal, wherein