JPH0334724Y2 - - Google Patents

Description

[Detailed explanation of the idea] (Technical field of invention) The present invention relates to improvements in optical fiber splitters.

(Technical background of the invention) Currently, optical fiber splitters are used as optical devices to branch optical signals from an optical fiber or to collect optical signals from two optical fibers into one optical fiber. .

As this type of optical fiber splitter, one is known that includes an optical branching member formed by side-welding a plurality of optical fibers and a connector plug attached to the optical branching member.

By the way, this type of optical fiber splitter conventionally involves stretching the fused portion of the optical branching member to an appropriate length to create a portion with the same outer diameter, and inserting and fixing this outer diameter portion into a connector plug. It is assembled by.

(Problems in the background art) However, it is extremely difficult to stretch the fused portion of the optical branching member to a constant outer diameter within the tolerance range because the fused portion is formed into a tapered shape by side fusion. , and requires advanced creation technology. For this reason, in the past, it took a lot of time and effort to manufacture an optical fiber splitter, and the splitter itself had the disadvantage of being expensive.

Furthermore, if the fused portion is stretched to a constant outer diameter, the optical fiber splitter becomes larger by that amount, which is another drawback.

(Object of the invention) An object of the invention is to provide an inexpensive and compact optical fiber splitter having a structure that is extremely easy to manufacture.

(Summary of the invention) The invention provides a branch connector plug with a small-diameter hole and a large-diameter hole that are opened on one end surface of the plug so as to communicate with each other, and the small-diameter portion of the tapered fused portion of the optical branching member is inserted into the small-diameter hole. At the same time as direct insertion, the large diameter part of the fused part is located in the large diameter hole, and one end surface of the plug is polished to near the position where the small diameter hole and the large diameter hole communicate with each other, thereby creating a tapered fused part. The present invention is characterized in that the small diameter portion of the fused portion is positioned within the plug with almost no error without providing portions with the same outer diameter.

(Embodiments of the invention) Hereinafter, embodiments of the invention will be described with reference to the drawings.

The optical fiber splitter according to the present invention includes an optical branching member 1, as shown in FIG. This optical branching member 1 includes a pair of optical fibers 2, 2 (see Fig. 2).
Fiber wires 2a, 2a exposed at one end side
It has a tapered fused part 3 formed by side-welding the ends of the fused part 3, and branch parts 4, 4 consisting of the fiber strands 2a continuous to the large diameter part 3a of this fused part 3. There is.

This optical branch member 1 is attached to a branch connector plug 5. The branch connector plug 5 has a small diameter hole 5a with a diameter of 120 to 125 μm that opens on one end side.
and a large-diameter hole 5b with a diameter of 280 to 300 μm, which is open on the other end surface side and communicates with the small-diameter hole 5a. The small diameter hole 5a has a length L of 500 μm before polishing, and the large diameter hole 5b has a length L' of 8 mm. The optical branch member 1 is connected to this branch connector plug 5.
The small diameter portion 3b of the fused portion 3 is fitted and fixed into the small diameter hole 5a of the plug 5, and the large diameter portion 3a of the fused portion 3 and the branch portions 4, 4 are placed in the large diameter hole 5b. However, in this state where the small diameter portion 3b is simply inserted into the small diameter hole 5a, the small diameter portion 3b is attached to the small diameter hole 5a.
Since b is tapered, there is a gap between the inner wall surface of the small diameter hole 5a and the circumferential surface of the tip of the small diameter portion 3b on the open end side of the small diameter hole 5a, and a gap exists between the center of the small diameter portion 3b and the center of the plug 5. There is a risk that an error may occur. Therefore, in the present invention, the branch connector plug 5
One end face of the hole 5 is polished to a width of several hundred μm along with the small diameter portion 3b up to the vicinity of the communication position P between the small diameter hole 5a and the large diameter hole 5b. Therefore, after polishing, the centers of the small diameter portion 3b and the plug 5 coincide with each other with high precision.

After polishing the branch connector plug 5, attach the connector plugs 6, 6 to the other ends of the optical fibers 2, 2, respectively, as shown in FIG. An optical fiber branching device is produced by molding the mixed fiber with epoxy resin 7 and storing it in a case.

In this way, when the branch connector plug 5 is directly attached to the fusion splice 3 without providing a portion with the same outer diameter, the case can be made smaller by that amount, and the optical fiber splitter can be made smaller. In addition, by simply fitting the small diameter portion 3b of the tapered fused portion 3 obtained only by side fusion of the optical fiber end into the small diameter hole 5a of the plug 5, and polishing the end surface of the plug 5, the fusion can be performed at the center of the plug 5. Since the centers of the attachment portions 3 can be aligned with high precision, an optical fiber splitter that is extremely easy to manufacture and inexpensive can be obtained.

FIG. 3 shows a branch connector plug 5 according to the present invention.
A modified example is shown. In this modification, an even larger diameter hole 5c is provided which communicates with the large diameter hole 5b, and a portion of the optical fibers 2, 2 near the optical branching member 1 is accommodated in this hole 5c.

(Effects of the invention) According to the invention, the small diameter portion of the tapered fused portion of the optical branching member is directly inserted into the small diameter hole of the branch connector plug to position the small diameter portion, and the end face of the plug is aligned with the fused portion. By polishing together with the small diameter part to the vicinity of the communication position between the large diameter hole of the plug where the large diameter part is arranged and the small diameter hole, the plug can be easily fused at the center of the plug without having the same outer diameter part in the fusion part. The centers of the parts can be aligned. Therefore, it is possible to provide an inexpensive optical fiber splitter that is small and extremely easy to manufacture.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a branch connector plug according to the present invention, Fig. 2 is a plan view showing an optical fiber splitter according to the present invention with the case omitted, and Fig. 3 is a modification of the branch connector plug according to the present invention. It is a sectional view showing an example. 1... Optical branching member, 2... Optical fiber, 3...
Fusion part, 3a...large diameter part, 3b...small diameter part,
4... Branch part, 5... Branch connector plug, 5a
...Small diameter hole, 5b...Large diameter hole.

Claims (1)

[Claims for Utility Model Registration] 1. Consisting of an optical branching member having a tapered fused portion formed by side-welding one ends of a plurality of optical fibers, and a branching connector plug attached to the optical branching member. In an optical fiber splitter,
The branch connector plug is open on one end side,
A small diameter hole into which the small diameter portion of the fused portion of the light branching member is inserted and fixed, and a large diameter hole communicating with the small diameter hole and in which the large diameter portion of the fused portion is disposed, are provided, respectively. An optical fiber splitter characterized in that one end surface is polished together with the small diameter portion to the vicinity of a communicating position between the small diameter hole and the large diameter hole. 2. The utility model registration claim is characterized in that the branch connector plug is provided with a hole of a larger diameter on the other end surface side, in which the optical fiber portion connected to the fused portion of the optical branch member is disposed. The optical fiber splitter according to scope 1.