JPS58193514A - Optical distributor and its manufacture - Google Patents

Abstract

PURPOSE:To obtain an optical distributor which is free of variance of distribution and mode dependency and has good operativity by tapering an optical fiber bundle, and then cutting a taper waist part and inserting a columnar optical member. CONSTITUTION:Optical fibers 31 and 32 are bundled and heat-sealed and both ends are drawn to form tapered parts 38 and 39. The taper waist part is cut and the columnar optical member 36 having nearly the same composition with the optical fibers 31 and 32 is connected to the cut surface 34 by sealing. The member 36 is cut to specific length and connected to the other end surface 35 by sealing to form a distributor. Consequently, light incident to the optical fiber 31 is converted by the tapered part from a code mode to a clad mode and diffused by the columnar member 36 to travel in the clad mode, so that it is distributed to optical fibers 31' and 32'. Therefore, this optical distributor is free of variance of distribution and mode dependency and has good operativity.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical field to which the invention pertains This invention relates to an optical splitter used in optical fiber communication and a manufacturing method thereof. In order to reduce mode dependence and distribution ratio variations, the optical distributor shown in Figures 1 and 2 has been proposed. Figure 111 shows optical 7 eyepers (1), <2) placed side by side, heated, bonded and tapered, both tapers 15 (1), (2) cut at the waist part (3) of the tapers, and then one side Taper IIt" is rotated 90 degrees, and the waist cutting surface (3
) to be heat fused. (Force, (8) is the core of the optical fiber, but as you can see from the A-A' cross section, this optical distributor also distributes light by overlapping cores, so
Dispersion of distribution and mode dependence are reduced. However, with this optical splitter, when the number of boats increases, it becomes difficult to line up the source fibers in a row and heat-seal them.Moreover, when the optical fiber is a converging type optical fiber, the light is concentrated at the center of the optical fiber core. Therefore, there is a drawback that light cannot be equally distributed to the cores of each fiber.

In addition, in the optical distributor shown in Fig. 2, columnar optical materials are fused and spliced between optical fibers aυ and 0 and 0 and 4, and the fibers are heated and fused and stretched so that the columnar optical materials become Taber waists. It is a light splitter with This optical distributor has a Theno (waisted columnar optical material a
! In No. 9, the mixture is mixed outside the core, so distribution variations and mode dependence are reduced. However, as the number of Koaino boats increases, it becomes extremely difficult to arrange them, as placing columnar optical members of fixed length between each of the seven Koaino boats requires a huge amount of work. .

OBJECTS OF THE INVENTION An object of the present invention is to improve the above-mentioned drawbacks, to provide an optical distributor that is free from distribution variations, mode dependence, and has good workability, and a method for manufacturing the same.

Summary of the invention That is, the optical distributor according to the present invention is made by bundling 97 eyepers into a tapered shape, cutting the vicinity of the taper waist M, and inserting a columnar optical material. The present invention will now be explained in detail.

The third factor-1 is an embodiment of the optical splitter according to the present invention.

clll(to) and 6υ(to) are optical fibers, each optical fiber is equipped with Taber S(to), OIt,
At the tip of the taper, it is connected to the columnar optical material at junctions m and (to). In this optical splitter, for example, if light is incident on the optical fiber □6υ,
The core mode of most of the light is converted to the cladding mode. However, there is also light in a low-order mode that maintains the core mode even with the Taber part, and the existence of this light in a low-order mode causes variation in the distribution ratio and mode dependence. The light distributor according to the present invention behaves as a cladding mode in the columnar optical material, including this low-order mode. In other words, even low-order mode light propagating through the optical fiber 0at is diffused by the columnar optical material and becomes light 7.
It has a structure in which it is distributed into eye/seat 6 and -. Theba S (to) is the light 7 eye pa o at the joint surface (to) of the tip of Te + Ha
6. The purpose of this is to convert the light from the cladding that cannot enter the core into the core mode. Therefore, the optical splitter according to the present invention also has the feature of low loss.

Figures 3(ml to 3(e)) show an example of a method for manufacturing an optical distributor according to the present invention. First, optical fibers /<01) and (to) are bundled, heat fused, and the fibers are Stretch both ends and make a taber as shown in (a). At this time, make sure that the cross section of the waist part is circular □.Next,
) Cut the waist part as shown in l.

Kirani (c) As shown in K, the columnar optical material Al19 is heat-bonded to the cutting gap. This columnar optical material is an optical fiber 6υ.

Materials with almost the same composition as (to) are suitable for heat fusion.

Also, the thickness should be the same as Teba's Quest) 4.

Next, the columnar optical material is cut to a predetermined length as shown in -. The columnar optical material requires at least several tens of times the outer diameter. Then, the columnar optical material is heat-sealed to the end face of the rear Fi (as shown in el) II and the columnar optical material. Note that as a heat source for thermal fusion, an oxyhydrogen burner, a gas discharge, an 00R radar, an electric heater, etc. may be used.

It goes without saying that it can be used as a columnar optical material in place of an optical fiber tube with a low NA.In addition, the Taber was made twice, cut to the same diameter each time, and each It may be manufactured using both sides of the same.

Effect of f&river Since the light distributor according to the present invention requires only one insertion of the columnar optical material, the work is particularly easy when manufacturing a light distributor for multiple boats, and there is no particularly difficult work. Furthermore, when increasing the number of ports, it is not necessary to arrange the optical fibers in a single row as shown in FIG. 4, so that fusion can be easily performed when tapering.

As explained above, according to the present invention, an optical distributor with small mode dependence and distribution ratio variation and low loss can be easily manufactured with good workability.

[Brief explanation of drawings]

#E1 and II2 are configuration diagrams of a conventional optical distributor, FIG. 3 is a working diagram of one embodiment of the present invention, and FIG. 4 is a diagram of another embodiment of the present invention. 0υ, (to), e6. ai, 稙υ, ゛(c), lord, (goods) tone, -1μη, 肱i, -9-...Optical fiber (to)
, C(7) , --... Columnar optical material (b), (c),
4. -...Cut plane @"L6υ, -... Taper department agent Patent attorney Noriyuki Chika (and 1 other person) No. 1
Figure 3 Figure 4 Procedure Amendment (Method) 195 production 6. 90 Commissioner of the Japan Patent Office 1. Indication of the case Patent Application No. 81 of 1981 2. Name of the invention Optical distributor and its manufacturing method 3. Relationship with the person making the amendment Patent applicant (307) Tokyo Shibaura Dankei Co., Ltd. Company No. 4 Managing Director 1-1-6 Uchisara-cho, Chiyo EB-ku, Tokyo 100 Tokyo Office, Toki Shibaura Electric Co., Ltd. 4L May 31, 158 (shipment date) 6. Subject to amendment Figure 1 M

Claims (3)

[Claims] (1) Each of the plurality of optical 7-eyepers is formed into a tapered line shape, and the first and second tapered fiber bundles are combined with the two layers of optical fiber glue at the tip end. The tapered tips of the Ml and second tapered fiber bundles have substantially equal diameters and face each other, and there is a gap between the image tips of the first and second tapered 7-eye fibers. A light distributor characterized in that the light distributor is connected by a columnar optical member having a diameter substantially equal to the diameter of the tip. (2) As a columnar optical material, the composition of Hikari 7 Eyepa is t! 2. A light distributor according to claim 1, characterized in that a material having an equally uniform refractive index is used. (3) Bundle multiple optical fibers and heat-fuse 5 parts,
The optical fiber is stretched to form a tapered shape and cut at a predetermined thickness of the tapered part to obtain the Ml and the second Taber 7 Aiba bundle, and the tip of the first Taber 7 Aiba bundle and the columnar shape are cut. The end face of the optical material is brought into contact with the end face of the optical material and heat fused, and if the columnar optical material is longer than necessary, the columnar optical material is cut to a predetermined length, and then the tip of the second Taber fiber bundle and the columnar optical material are A method for manufacturing an optical distributor, characterized in that the end faces of the remaining optical materials are brought together and thermally fused and connected.