JPS6232444B2 - - Google Patents
Info
- Publication number
- JPS6232444B2 JPS6232444B2 JP59222972A JP22297284A JPS6232444B2 JP S6232444 B2 JPS6232444 B2 JP S6232444B2 JP 59222972 A JP59222972 A JP 59222972A JP 22297284 A JP22297284 A JP 22297284A JP S6232444 B2 JPS6232444 B2 JP S6232444B2
- Authority
- JP
- Japan
- Prior art keywords
- optical fiber
- optical
- tapered
- fiber bundle
- optical fibers
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 239000013307 optical fiber Substances 0.000 claims description 91
- 239000000835 fiber Substances 0.000 claims description 17
- 238000004519 manufacturing process Methods 0.000 claims description 14
- 238000005253 cladding Methods 0.000 claims description 11
- 238000010438 heat treatment Methods 0.000 claims description 9
- 238000000034 method Methods 0.000 claims description 6
- 239000000463 material Substances 0.000 claims 1
- 238000004804 winding Methods 0.000 claims 1
- 230000003287 optical effect Effects 0.000 description 21
- 238000010586 diagram Methods 0.000 description 6
- 238000007796 conventional method Methods 0.000 description 4
- 238000009826 distribution Methods 0.000 description 3
- 230000005855 radiation Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 2
- 239000003365 glass fiber Substances 0.000 description 2
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- 238000005452 bending Methods 0.000 description 1
- 230000004927 fusion Effects 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 230000000644 propagated effect Effects 0.000 description 1
- 230000001902 propagating effect Effects 0.000 description 1
Landscapes
- Optical Fibers, Optical Fiber Cores, And Optical Fiber Bundles (AREA)
Description
【発明の詳細な説明】
〔発明の技術分野〕
本発明は、例えば光フアイバ通信用の光分配器
として用いられるテーパ状光フアイバ束の製造方
法に関する。DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a method for manufacturing a tapered optical fiber bundle used, for example, as an optical distributor for optical fiber communications.
第２図は、テーパ状光フアイバ束の一つの応用
例である、光分配器を示したものである。図にお
いて、２１１，２１２はテーパ状光フアイバ束で
あり、２２はこれらの光フアイバ束２１１，２１
２を連結する、均一な屈折率を有するミキサロツ
ドである。この光分配器の光学的動作は次の通り
である。いま、左側の光フアイバ束２１１を入力
側とすると、この光フアイバ束２１１の任意の光
フアイバに入射した光は、そのテーパ部で導波モ
ードからクラツドモードに変換され、ミキシング
される。さらにその光は、ミキサロツド２２によ
つてほぼ完全にミキシングされて右側の光フアイ
バ束２１２に伝搬され、クラツドモードから導波
モードに変換されてテーパ状光フアイバ束２１２
を構成する各光フアイバに均一に分配される。例
えば、光フアイバ束２１１がｎ本の光フアイバか
らなり、光フアイバ束２１２がｍ本の光フアイバ
からなる場合、この光分配器はｎ×ｍ光分配器と
して作用する。
FIG. 2 shows an optical distributor, which is one application example of a tapered optical fiber bundle. In the figure, 21 1 , 21 2 are tapered optical fiber bundles, and 22 is these optical fiber bundles 21 1 , 21
It is a mixer rod with a uniform refractive index that connects the two . The optical operation of this optical distributor is as follows. Now, assuming that the optical fiber bundle 211 on the left side is the input side, light incident on any optical fiber of this optical fiber bundle 211 is converted from a waveguide mode to a cladding mode at its tapered portion and mixed. Further, the light is almost completely mixed by the mixer rod 22 and propagated to the optical fiber bundle 212 on the right side, where the cladding mode is converted into a waveguide mode and the tapered optical fiber bundle 212
is evenly distributed to each optical fiber that makes up the fiber. For example, if the optical fiber bundle 21 1 consists of n optical fibers and the optical fiber bundle 21 2 consists of m optical fibers, this optical splitter acts as an n×m optical splitter.
テーパ状光フアイバ束は、以上の応用例の他、
１×ｎ光分配器や各種光結合器などにも用いるこ
とができる。 In addition to the above-mentioned applications, tapered optical fiber bundles can also be used for
It can also be used for 1×n optical splitters and various optical couplers.
第３図は、この様な光分配器を構成するテーパ
状光フアイバ束の従来の製造方法を示すものであ
る。第３図ａに示すように、洗浄した複数本の光
フアイバ３１を最密状態になるように束ね、その
一部を第３図ｂに示すようにバーナ３２等の加熱
手段を用いて加熱し、これを第３図ｃに示すよう
に引き伸ばしてテーパ部を形成する。このように
してつくられるテーパ状光フアイバ束は、テーパ
部において各光フアイバのクラツド層が互いに融
着されて一体化構造をなしている。 FIG. 3 shows a conventional method of manufacturing a tapered optical fiber bundle constituting such a light distributor. As shown in FIG. 3a, a plurality of cleaned optical fibers 31 are bundled in a close-packed state, and a portion of the cleaned optical fibers 31 is heated using a heating means such as a burner 32 as shown in FIG. 3b. , this is stretched to form a tapered portion as shown in FIG. 3c. The tapered optical fiber bundle thus produced has an integrated structure in which the cladding layers of each optical fiber are fused to each other at the tapered portion.
ところで、このような従来の光フアイバ束の製
造方法においては、束ねる光フアイバの本数が増
す程、テーパ部で各光フアイバが完全に融着する
ことの歩留りが低下する傾向がある。光フアイバ
の本数は通常２〜100本であるが、例えば30本程
度では全光フアイバが融着される歩留りは20％程
度になつてしまう。 By the way, in such a conventional method for manufacturing an optical fiber bundle, as the number of optical fibers to be bundled increases, the yield rate of completely fusing each optical fiber at the tapered portion tends to decrease. The number of optical fibers is usually 2 to 100, but if there are, for example, about 30 optical fibers, the yield of all the optical fibers being fused will be about 20%.
光フアイバの本数が増した時に、テーパ状光フ
アイバ束の製造歩留りを向上させる方法として、
光フアイバ束をねじりながら引張る方法が知られ
ている。その製造工程を第４図に示す。第４図ａ
に示すように、複数本の光フアイバ３１を最密状
態になるように束ねて、その一部をバーナ３２等
の加熱手段で加熱し、第４図ｂに示すように光フ
アイバ３１の束にねじりを加えながら引張ること
により、第４図ｃに示すようにテーパ部を形成す
る。この場合、高い歩留りを確保するためには、
ねじる角度を180度以上にする必要があることが
経験的に知られている。 As a method to improve the manufacturing yield of tapered optical fiber bundles when the number of optical fibers increases,
A method is known in which an optical fiber bundle is pulled while being twisted. The manufacturing process is shown in FIG. Figure 4a
As shown in FIG. 4B, a plurality of optical fibers 31 are bundled in a close-packed state, and a part of the fibers is heated with a heating means such as a burner 32 to form a bundle of optical fibers 31 as shown in FIG. 4B. By pulling while applying twist, a tapered portion is formed as shown in FIG. 4c. In this case, to ensure high yield,
It is known from experience that the twist angle needs to be 180 degrees or more.
しかしながら、この様なねじりを加えながらの
加工を行なつて得られたテーパ状光フアイバ束を
第２図に示すような光分配器に用いると、光を均
等に分配する機能が低下することが実験的に確認
された。その原因として、
束ねた光フアイバの中心近傍に位置するもの
と外周部に位置するものでは、ねじれ方が異な
る、
ねじりを加えた時に光フアイバの整列が乱
れ、この整列の乱れに起因して各光フアイバに
異なる曲り応力が加わる、
などが考えらえれ、その結果導波モードとクラツ
ドモードの変換・再変換が均一に行われなくなる
ものである。 However, when a tapered optical fiber bundle obtained through processing with such twisting is used in an optical distributor as shown in Figure 2, the ability to evenly distribute light may deteriorate. Confirmed experimentally. The reason for this is that the optical fibers located near the center of the bundle are twisted differently than those located on the outer periphery.When twisting is applied, the alignment of the optical fibers is disturbed, and this disturbance in alignment causes each fiber to be twisted differently. It is possible that different bending stresses are applied to the optical fiber, and as a result, the guided mode and cladding mode are not converted and reconverted uniformly.
本発明は上述した欠点を改良するもので、光分
配器に適用したときに各出力光フアイバへ分配さ
れる光のばらつきが小さいテーパ状光フアイバ束
を歩留り良く製造する方法を提供することを目的
とする。
SUMMARY OF THE INVENTION The present invention aims to improve the above-mentioned drawbacks, and aims to provide a method for manufacturing a tapered optical fiber bundle with high yield in which when applied to an optical distributor, the variation in light distributed to each output optical fiber is small. shall be.
本発明は、複数本の光フアイバをほぼ最密状態
に束ね、これに整列用の光フアイバを巻きつけ
て、上記複数本の光フアイバの一部を加熱しなが
ら、光フアイバの束に極力ねじりを加えないよう
にして引き伸ばしてテーパ状に加工することを特
徴とする。
The present invention involves bundling a plurality of optical fibers in a nearly dense state, wrapping optical fibers for alignment around this, and twisting the bundle of optical fibers as much as possible while heating a part of the plurality of optical fibers. It is characterized by stretching and processing it into a tapered shape without adding any.
本発明によれば、整列用の光フアイバが複数本
の光フアイバの束の整列状態をより緊密に保つた
め、テーパ加工時の熱融着の成功率を高めること
ができ、したがつてテーパ状光フアイバ束の製造
歩留りを高めることができる。更に、光フアイバ
束にねじりを加えないようにしてテーパ加工する
ため、本発明の方法により得られるテーパ状光フ
アイバ束を光分配器に適用した時に、各出力光フ
アイバへの光の分配が均等になるという効果が得
られる。
According to the present invention, since the optical fibers for alignment keep the bundle of optical fibers more closely aligned, it is possible to increase the success rate of thermal fusion during taper processing, and therefore the tapered The manufacturing yield of optical fiber bundles can be increased. Furthermore, since the optical fiber bundle is tapered without twisting, when the tapered optical fiber bundle obtained by the method of the present invention is applied to an optical splitter, the light is evenly distributed to each output optical fiber. You can get the effect of becoming.
以下本発明の実施例を説明する。 Examples of the present invention will be described below.
第１図は一実施例の製造工程を示すものであ
る。まず、第１図ａに示すように、洗浄した複数
本の光フアイバ１１をほぼ最密状態になるように
束ね、これに整列用の光フアイバ（以下、補助フ
アイバという）１２を巻きつける。光フアイバ１
１が多成分系ガラスからなるステツプ・インデツ
クス形フアイバのばあい、補助フアイバ１２とし
ては、光フアイバ１１のクラツド層の屈折率以下
の屈折率を持ち、軟化点が光フアイバ１１のそれ
とほぼ等しい、コアのない均質なガラスフアイバ
を用いる。この補助フアイバ１２の両端は、機械
的にまたは接着材やワツクスなどを用いて光フア
イバ１１の束に固定しておく。この後、第１図ｂ
に示すように、バーナ１３等の加熱手段により束
ねた光フアイバ１１の一部を加熱し、極力ねじり
を加えないようにして第１図ｃに示すように引き
伸ばしてテーパ加工を行なう。 FIG. 1 shows the manufacturing process of one embodiment. First, as shown in FIG. 1a, a plurality of cleaned optical fibers 11 are bundled in a substantially close-packed state, and optical fibers 12 for alignment (hereinafter referred to as auxiliary fibers) are wound around this. optical fiber 1
In the case of a step-index fiber 1 made of multi-component glass, the auxiliary fiber 12 has a refractive index lower than the refractive index of the cladding layer of the optical fiber 11 and a softening point approximately equal to that of the optical fiber 11. A homogeneous glass fiber without a core is used. Both ends of the auxiliary fiber 12 are fixed to the bundle of optical fibers 11 mechanically or using adhesive, wax, or the like. After this, Figure 1b
As shown in FIG. 1C, a part of the bundled optical fibers 11 is heated by a heating means such as a burner 13, and the optical fibers 11 are stretched and tapered as shown in FIG. 1C while minimizing twisting.
この実施例によれば、束ねた光フアイバ１１の
整列状態が補助フアイバ１２により保持される結
果、本数が多い場合にも全光フアイバが確実に融
着される。またテーパ加工時にねじりを与えてい
ないから、得られたテーパ状光フアイバ束を用い
て光分配器を構成した時、各出力光フアイバへの
光分配は均等に行われる。更にこの実施例では、
補助フアイバ１２として光フアイバ１１のクラツ
ド層の屈折率以下の屈折率を持つガラスフアイバ
を用いているため、テーパ加工後はこの補助フア
イバ１２はそのまま光フアイバ束のクラツド層と
して作用する。従つてこの補助フアイバ１２によ
る光の損失は殆どない。ところで、厳密には本発
明のように束ねた光フアイバ１１のテーパ状部分
のクラツド層の外側に補助光フアイバ１２がある
と、伝搬する光は一部がテーパ状部分において光
フアイバ１１のクラツド層から補助光フアイバ１
２中に進行し、さらにその一部が補助光フアイバ
１２の端面から外部へ漏れ出て一種の放射損失が
生じる。この放射損失の大きさは補助光フアイバ
１２による光フアイバ束のクラツド層の断面積の
増加に依存するが、補助光フアイバによる光フア
イバ束全体としての断面積の増加は極く僅かであ
るから、この放射損失の増加は無視できる程度に
抑えられる。 According to this embodiment, the aligned state of the bundled optical fibers 11 is maintained by the auxiliary fibers 12, so that all the optical fibers are reliably fused even when there are a large number of optical fibers. Further, since no twist is applied during taper processing, when an optical distributor is constructed using the obtained tapered optical fiber bundle, light is evenly distributed to each output optical fiber. Furthermore, in this example,
Since a glass fiber having a refractive index lower than the refractive index of the cladding layer of the optical fiber 11 is used as the auxiliary fiber 12, the auxiliary fiber 12 acts as it is as the cladding layer of the optical fiber bundle after tapering. Therefore, there is almost no loss of light through this auxiliary fiber 12. By the way, strictly speaking, if the auxiliary optical fiber 12 is placed outside the cladding layer of the tapered portion of the bundled optical fibers 11 as in the present invention, a portion of the propagating light will pass through the cladding layer of the optical fiber 11 in the tapered portion. to auxiliary optical fiber 1
2, and a part of it leaks out from the end face of the auxiliary optical fiber 12, causing a kind of radiation loss. The magnitude of this radiation loss depends on the increase in the cross-sectional area of the cladding layer of the optical fiber bundle due to the auxiliary optical fiber 12, but since the increase in the cross-sectional area of the optical fiber bundle as a whole due to the auxiliary optical fiber is extremely small, This increase in radiation loss is suppressed to a negligible level.
本実施例によるテーパ状光フアイバ束を用いて
構成した光分配器の特性が優れていることを、デ
ータに基いて明らかにする。第５図は、本実施例
により得られたテーパ状光フアイバ束を用いた光
分配器の、全ての入力フアイバと出力フアイバの
組み合わせに対する過剰損失のヒストグラムであ
る。ここで、過剰損失とは、理想的な光分配が行
われた場合の損失（例えば２分配の場合であれ
ば、3dB）と他の要因による損失を含む現実の損
失との差をいう。第６図は、第４図で説明した従
来の方法によるテーパ状光フアイバ束を用いた光
分配器の過剰損失のヒストグラムである。両者を
比較すれば明らかなように、本実施例によるテー
パ状光フアイバ束を用いた光分配器に於ける光の
分配の均一性は、従来法によるテーパ状光フアイ
バ束を用いた光分配器に比べてはるかに優れてい
る。 It will be clarified based on data that the optical distributor constructed using the tapered optical fiber bundle according to this example has excellent characteristics. FIG. 5 is a histogram of excess loss for all input fiber and output fiber combinations of the optical splitter using the tapered optical fiber bundle obtained in this example. Here, the excess loss refers to the difference between the loss when ideal optical distribution is performed (for example, 3 dB in the case of two distribution) and the actual loss including loss due to other factors. FIG. 6 is a histogram of excess loss of an optical splitter using a tapered optical fiber bundle according to the conventional method described in FIG. As is clear from comparing the two, the uniformity of light distribution in the optical distributor using the tapered optical fiber bundle according to this embodiment is higher than that in the optical distributor using the tapered optical fiber bundle according to the conventional method. much better than.
本発明は上記実施例に限られるものではない。
例えば補助フアイバは１本でなくてもよく、束ね
る光フアイバの本数等に応じて２〜３本用いても
よい。また本発明に於ける整列部材のまきつけ
は、加熱部の全域に限らず、テーパ部の一部であ
つてもよい。また加熱手段としては、バーナの
他、気体放電、CO2ガスレーザなどを用いること
ができる。 The present invention is not limited to the above embodiments.
For example, the number of auxiliary fibers does not need to be one; two or three may be used depending on the number of optical fibers to be bundled. Further, in the present invention, the alignment member may be wrapped around not only the entire area of the heating section but also a part of the tapered section. Further, as the heating means, in addition to a burner, gas discharge, CO 2 gas laser, etc. can be used.
第１図ａ〜ｃは本発明の一実施例のテーパ状光
フアイバ束の製造工程を示す図、第２図はテーパ
状光フアイバ束を用いた光分配器の構成例を示す
図、第３図ａ〜ｃは従来のテーパ状光フアイバ束
の製造工程例を示す図、第４図ａ〜ｃは従来のテ
ーパ状光フアイバ束の他の製造工程例を示す図、
第５図は実施例により得られた光フアイバ束を用
いて構成した光分配器の過剰損失ヒストグラムを
示す図、第６図は第４図で説明した従来法による
テーパ状光フアイバ束を用いて構成した光分配器
の過剰損失ヒストグラムを示す図である。
１１……光フアイバ、１２……補助フアイバ
（整列部材）、１３……バーナ。
1A to 1C are diagrams showing the manufacturing process of a tapered optical fiber bundle according to an embodiment of the present invention, FIG. 2 is a diagram showing an example of the configuration of an optical distributor using a tapered optical fiber bundle, and FIG. Figures a to c are diagrams showing an example of a conventional manufacturing process for a tapered optical fiber bundle, and Figures 4a to c are diagrams showing another example of a manufacturing process for a conventional tapered optical fiber bundle.
FIG. 5 is a diagram showing an excess loss histogram of an optical splitter constructed using the optical fiber bundle obtained in the example, and FIG. FIG. 6 is a diagram showing an excess loss histogram of the configured optical splitter. 11... Optical fiber, 12... Auxiliary fiber (alignment member), 13... Burner.
Claims (1)
して引き伸ばすことによりテーパ状光フアイバ束
を製造する方法において、束ねた複数本の光フア
イバの加熱部に整列用の光フアイバを巻きつけて
加熱、引き伸ばし加工を行なうことを特徴とする
テーパ状光フアイバ束の製造方法。 ２ 前記整列用の光フアイバは、その屈折率が前
記複数本の光フアイバのクラツド層の屈折率以下
である均質な物質からなることを特徴とする特許
請求の範囲第１項記載のテーパ状光フアイバ束の
製造方法。[Claims] 1. In a method of manufacturing a tapered optical fiber bundle by bundling a plurality of optical fibers and heating and stretching a part of the fibers, a heating part of the bundled plurality of optical fibers is provided for alignment. A method for producing a tapered optical fiber bundle, which comprises winding optical fibers, heating and stretching them. 2. The tapered light beam according to claim 1, wherein the alignment optical fiber is made of a homogeneous material whose refractive index is less than or equal to the refractive index of the cladding layer of the plurality of optical fibers. Method for manufacturing fiber bundles.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22297284A JPS61102613A (en) | 1984-10-25 | 1984-10-25 | Production of tapered optical fiber bundle |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22297284A JPS61102613A (en) | 1984-10-25 | 1984-10-25 | Production of tapered optical fiber bundle |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS61102613A JPS61102613A (en) | 1986-05-21 |
| JPS6232444B2 true JPS6232444B2 (en) | 1987-07-15 |
Family
ID=16790772
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP22297284A Granted JPS61102613A (en) | 1984-10-25 | 1984-10-25 | Production of tapered optical fiber bundle |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS61102613A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH05142446A (en) * | 1991-11-22 | 1993-06-11 | Seiko Giken:Kk | Optical branching/coupling device and production thereof |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58193515A (en) * | 1983-03-24 | 1983-11-11 | Toshiba Corp | Manufacture of optical distributor |
| JPS59195615A (en) * | 1983-04-21 | 1984-11-06 | Sumitomo Electric Ind Ltd | Production of branch of optical fiber |
| JPS60150011A (en) * | 1984-01-18 | 1985-08-07 | Fuji Electric Corp Res & Dev Ltd | Manufacture of optical demultiplexing and multiplexing part |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS54112021U (en) * | 1978-01-20 | 1979-08-07 |
-
1984
- 1984-10-25 JP JP22297284A patent/JPS61102613A/en active Granted
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58193515A (en) * | 1983-03-24 | 1983-11-11 | Toshiba Corp | Manufacture of optical distributor |
| JPS59195615A (en) * | 1983-04-21 | 1984-11-06 | Sumitomo Electric Ind Ltd | Production of branch of optical fiber |
| JPS60150011A (en) * | 1984-01-18 | 1985-08-07 | Fuji Electric Corp Res & Dev Ltd | Manufacture of optical demultiplexing and multiplexing part |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS61102613A (en) | 1986-05-21 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EXPY | Cancellation because of completion of term |