JPS60154204A - Multicore optical fiber and its manufacture - Google Patents
Multicore optical fiber and its manufactureInfo
- Publication number
- JPS60154204A JPS60154204A JP59011425A JP1142584A JPS60154204A JP S60154204 A JPS60154204 A JP S60154204A JP 59011425 A JP59011425 A JP 59011425A JP 1142584 A JP1142584 A JP 1142584A JP S60154204 A JPS60154204 A JP S60154204A
- Authority
- JP
- Japan
- Prior art keywords
- optical fiber
- core
- plastic
- coating
- bonded
- 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.)
- Pending
Links
- 239000013307 optical fiber Substances 0.000 title claims description 35
- 238000004519 manufacturing process Methods 0.000 title claims description 11
- 239000011248 coating agent Substances 0.000 claims description 17
- 238000000576 coating method Methods 0.000 claims description 17
- 239000004033 plastic Substances 0.000 claims description 15
- 229920003023 plastic Polymers 0.000 claims description 15
- 239000000835 fiber Substances 0.000 claims description 14
- 239000003365 glass fiber Substances 0.000 claims 3
- 239000010410 layer Substances 0.000 description 13
- 238000005253 cladding Methods 0.000 description 7
- 238000000034 method Methods 0.000 description 7
- 230000003287 optical effect Effects 0.000 description 5
- 230000000694 effects Effects 0.000 description 4
- 239000002904 solvent Substances 0.000 description 4
- 238000007526 fusion splicing Methods 0.000 description 3
- 238000010438 heat treatment Methods 0.000 description 3
- 230000003014 reinforcing effect Effects 0.000 description 3
- 229920002050 silicone resin Polymers 0.000 description 3
- 239000004677 Nylon Substances 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 2
- 238000004891 communication Methods 0.000 description 2
- 230000004927 fusion Effects 0.000 description 2
- 229920001778 nylon Polymers 0.000 description 2
- 229920005989 resin Polymers 0.000 description 2
- 239000011347 resin Substances 0.000 description 2
- 239000007921 spray Substances 0.000 description 2
- 239000004593 Epoxy Substances 0.000 description 1
- JOYRKODLDBILNP-UHFFFAOYSA-N Ethyl urethane Chemical compound CCOC(N)=O JOYRKODLDBILNP-UHFFFAOYSA-N 0.000 description 1
- NIXOWILDQLNWCW-UHFFFAOYSA-N acrylic acid group Chemical group C(C=C)(=O)O NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- -1 etc. Polymers 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 239000006223 plastic coating Substances 0.000 description 1
- 229920005749 polyurethane resin Polymers 0.000 description 1
- 239000011241 protective layer Substances 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/44—Mechanical structures for providing tensile strength and external protection for fibres, e.g. optical transmission cables
- G02B6/4401—Optical cables
- G02B6/4403—Optical cables with ribbon structure
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/04—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings formed by bundles of fibres
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Manufacture, Treatment Of Glass Fibers (AREA)
- Optical Fibers, Optical Fiber Cores, And Optical Fiber Bundles (AREA)
Abstract
(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.
Description
【発明の詳細な説明】
（技術分野）
本発明は、７本の通信用光ファイバの中に複数心の光フ
ァイバを含む多心光ファイバ素線に関するものである。DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a multi-core optical fiber wire including a plurality of optical fibers among seven communication optical fibers.
（従来技術とその問題点）
高密度で多心の通信用光ファイバとしては、従来ン本の
光ファイバの中に複数本のコアが共通のクラッドの中に
配置された第１図のようなマルチコアファイバタイプ（
同図において１はコア、２はクラッド）、あるいは第２
図のようにクラッドが接点で１１％したパンチファイバ
タイプ（同図において１はコア、２はクラッド）と、単
心の素線あるいは心線が複数本束ねられた第３図のよう
な光ケーブルタイプ（同図において１はコア、２はクラ
ッド、３はシリコン樹脂−４はナイロン）がある。(Prior art and its problems) As a high-density, multi-core communication optical fiber, conventional optical fibers have multiple cores arranged in a common cladding, as shown in Figure 1. Multi-core fiber type (
In the figure, 1 is the core, 2 is the cladding), or the second
As shown in the figure, there is a punch fiber type in which the cladding is 11% at the contact point (in the figure, 1 is the core and 2 is the cladding), and an optical cable type in which a single core wire or multiple core wires are bundled together as shown in Figure 3. (In the figure, 1 is a core, 2 is a cladding, 3 is a silicone resin, and 4 is a nylon).
前者のクラッドが共通あるいは接した一体桝造の多心光
ファイバは、高密度多心ケーブルを実玩する上で極めて
有用で、また、その形状から光フアイバ同志の一括接続
が容易であるという利点がある。しかし、光フアイバ両
端において各コアを別々に光信号を入射励振し、また、
光信号を取出すために分岐することが困絵であるという
欠点がある。The former type of multi-core optical fiber with a single-walled structure in which the cladding is common or in contact is extremely useful for experimenting with high-density multi-core cables, and also has the advantage that it is easy to connect optical fibers together due to its shape. There is. However, each core is separately excited with an optical signal at both ends of the optical fiber, and
The disadvantage is that it is difficult to branch to extract the optical signal.
一方、後者の光ケーブルタイプは前者に比べ、両端末の
処理は容易であるが、高密度化と接続の容易さの点゛（
・劣っている。On the other hand, the latter optical cable type is easier to process both terminals than the former, but has the disadvantages of high density and ease of connection.
・Inferior.
（発明の構成と実施例）
本発明は、上記の点に倣みなされた多心光ファイバで、
薄肉の補強層をコーティングした単心の光ファイバが伽
数本互いに接着した構造を特徴とし、高密度化、一括接
続２分岐が可能なものである０
第４図は本発明による多心光ファイバ構造例で同図（イ
）は同心状７心光フアイバ、（→は平型を心光ファイバ
を示す。５は薄肉のプラスチック−次装置で、製造時多
心を束ねる際、および接続時、シリコン樹脂等よりなる
二次ｈａ除去の際、ファイバを外傷より保護するために
設けた補強層で、エポキシ糸、ウレタン糸、アクリル糸
等の樹脂を利用できる。６は一部′ｆ＆ｍをさらに補強
するためのプラスチック等からなる二次被覆で、シリコ
ン樹脂、ポリウレタン樹脂等が用いられる。(Structure and Embodiments of the Invention) The present invention is a multi-core optical fiber that is based on the above points,
It is characterized by a structure in which a small number of single-core optical fibers coated with a thin reinforcing layer are bonded to each other, and it is possible to increase the density and connect them at once into two branches.0 Figure 4 shows a multi-core optical fiber according to the present invention. In the structural example, (a) in the same figure shows a concentric 7-core optical fiber, (→ indicates a flat core optical fiber. 5 is a thin-walled plastic-type device, which is used when bundling multiple fibers during manufacturing and when connecting. This is a reinforcing layer provided to protect the fiber from damage when removing the secondary ha made of silicone resin, etc., and resins such as epoxy thread, urethane thread, acrylic thread, etc. can be used. 6 further reinforces some 'f&m' A secondary coating made of plastic, etc., used for coating, such as silicone resin, polyurethane resin, etc.
第５図は本発明による多心光フアイバ素線の別の構造例
である。−次被搬層は２層の異種プラスチツ４りからな
り、第１層５′は製造、接続時の外傷からの保論層で、
各ファイバは第２層５″により互いに接着し・第１層５
′に比べ溶剤に容易に溶ける相質を選択することにより
、ファイバに外傷を与えることなく分岐できる。なお、
６はブラスチツクニ次扱激である。FIG. 5 shows another structural example of a multi-core optical fiber according to the present invention. - The next transfer layer consists of two layers of dissimilar plastics, the first layer 5' being a protective layer from damage during manufacturing and connection;
Each fiber is bonded together by a second layer 5'' and a first layer 5''.
By selecting a phase that is more easily soluble in solvents than ', branching can be achieved without damaging the fibers. In addition,
6 is a blast to deal with.
第４図および第５図に示した構造は、図示した以外にい
かなる心数の多心光ファイバに対しても適用できる。The structures shown in FIGS. 4 and 5 can be applied to multi-core optical fibers having any number of fibers other than those shown.
本発明における多心光ファイバのプラスチック １−次
に＆の厚さはコア寸法によって規定される。 ′厚い一
部級波を均一に施すのは齢かしく、一方一括融着接続時
コアの位置決めは、コアが中心にあることを前提に■溝
等を利用する方法が一般に行われ、−次扱櫃の偏肉と接
続点での伝送損失の間に密接な関係が存在するためであ
る。Plastic of Multicore Optical Fiber in the Invention 1-The thickness of the & is defined by the core dimensions. ``It is old-fashioned to uniformly apply thick, one-grade waves; on the other hand, when positioning the core during bulk fusion splicing, it is generally done by using grooves, etc., assuming that the core is in the center. This is because there is a close relationship between uneven thickness of the box and transmission loss at the connection point.
、第６図に光ファイバの軸ずれ量と接続効率の関係を測
定した結果を示す。同図によれは、−次被覆の厚さく偏
肉がある場合は平均厚）がコア半径のゾ３以下の場合は
、いかに−次被億の偏肉が大きくても正規化軸ずれ量は
偽以下となり、接続効果は０５以上にすることができる
。, FIG. 6 shows the results of measuring the relationship between the amount of optical fiber axis misalignment and the splicing efficiency. According to the figure, if the thickness of the -th coating (or average thickness if there is an uneven thickness) is less than 3 of the core radius, no matter how large the uneven thickness of the -th cover, the normalized axis deviation amount is It becomes false or lower, and the connection effect can be 05 or higher.
接続点での伝送損失の点以外でも一般にプラスチック−
次被覆は、製造、接続時の補強効果に影智を受けない範
囲で薄い方が望ましい。Other than the transmission loss at the connection point, plastics are generally
It is desirable that the next coating be as thin as possible without affecting the reinforcing effect during manufacturing and connection.
それは、一括融着接続時、−次被億が厚いと、プラスチ
ックの燃焼１分解が不完全となりやすく、気泡の発生や
接続強度の低さを引き起こすからである。This is because, when bulk fusion splicing is performed, if the cladding is thick, the combustion and decomposition of the plastic tends to be incomplete, resulting in the generation of bubbles and low joint strength.
第７図に本発明による多心光ファイバの製造方法の一例
ヲ庁、ス。これに基づいて本発明の製造方法を説明する
。FIG. 7 shows an example of the method for manufacturing a multi-core optical fiber according to the present invention. Based on this, the manufacturing method of the present invention will be explained.
多数本の光フアイバプリフォーム１１を同時に線引炉１
２で加熱線引きした直後に、−次被覆をコーティングす
る。−次ｍｍをする方法としては、一般にスプレー法か
用いられ、本例ではスプレーノズル１３より噴出した一
次被覆プラスチック原料は各ファイバ表面に薄く付着し
、その直後硬化炉１４により硬化する（スプレー法以外
にもフェルトでコーティングする等の方法もある）。そ
の後、絞りダイス１５により一括集合された後、−次被
覆プラスチックを溶融軟化または溶剤塗布加熱等の方法
として弗７図では軟化融着炉１６により融着し、さらに
プラスチックの二次被覆をコーティングする。本例では
加熱融着により一次被覆プラスチック層を融着し、コー
ティングダイス１７により二次［１ｔプラスチツク液を
塗布し、硬化炉１Ｂで硬化すせ、巻取機１９に巻取る。A large number of optical fiber preforms 11 are simultaneously drawn in the drawing furnace 1.
Immediately after hot drawing in step 2, a second coating is applied. - Spraying is generally used as a method for coating the fibers. There are also methods such as coating it with felt). Thereafter, after being gathered together by a drawing die 15, the secondary coated plastic is melted and softened or melted and bonded in a softening and fusing furnace 16 using a method such as solvent coating and heating, and further coated with a secondary plastic coating. . In this example, the primary coating plastic layer is fused by heat fusion, a secondary [1t plastic liquid is applied by a coating die 17, hardened in a curing furnace 1B, and wound up by a winder 19.
第８図に本発明による多心光コアイノ々の異なる製造方
法例を示す。FIG. 8 shows examples of different methods of manufacturing multi-core optical cores according to the present invention.
２層の異棟プラスチックの一次被覆を図示するようにス
プレーノズル１３′および１３でコーティングした直後
（各ノズル通過後第１硬化炉１４．第２硬化炉１４′′
を通る）・複数本のファイバを絞りダイス１５′で絞り
ながら第２層のみを溶解する溶剤を塗布した後加熱炉１
６で加熱し、二次ｈａミコーティングダイス１フ次いで
硬化炉１８を経て第５図に示すような構造の多心光ファ
イバが得られ、巻取機１９に巻取られる。Immediately after coating the two-layer plastic primary coating with spray nozzles 13' and 13 as shown (after passing through each nozzle, the first curing oven 14, the second curing oven 14''
)・After applying a solvent that dissolves only the second layer while squeezing the multiple fibers with a squeezing die 15', the heating furnace 1
6, passed through a secondary hami coating die and then through a curing furnace 18 to obtain a multi-core optical fiber having a structure as shown in FIG. 5, which was then wound into a winder 19.
（発明の効果）
本発明の多心光ファイバは、薄い一部被覆プラスチック
で互いに融着しているため、一括接続が可能であるが、
溶剤等を用いてその被握層を除去することが口」能なた
め、バラバラに分岐できる効果を有しているので、従来
にない脩れた高密度光ファイバケーブル用ファイバとし
て利用できるものである。(Effects of the Invention) Since the multi-core optical fibers of the present invention are fused to each other with thin partially coated plastic, it is possible to connect them all at once.
Since it is possible to remove the gripping layer using a solvent, etc., it has the effect of being able to branch into pieces, so it can be used as a fiber for unprecedented high-density optical fiber cables. be.
また、その映造方法も複数本のガラスコアイノくを同時
に互いに接触させずに線引した直後、コーティングを施
すため、高強度のファイバが得られ、また、−良の紛引
により多心の素棚が得られ、量産性に擾れているという
効果を有している。In addition, the projection method uses coating immediately after drawing multiple glass cores without contacting each other at the same time, resulting in a high-strength fiber. This has the effect of hindering mass production.
第１図はマルチコアファイバの断面図、第２図はパンチ
ファイバの断面図、第３図は多心光フアイバ心線の断面
図、第４図は本発明の多心光ファイバの実施例で、（イ
）は同心状多心光ファイバの断面図、（ロ）は平型を心
光ファイバの断面図、第５図は本発明の多心光フアイバ
素線の構造側断面図。
第６図は光ファイバの融着接続時における軸すれ量と接
続効率の関係測定結果のグラフ、第７−１第８図は本発
明の多心光ファイバのそれぞれ異なる製造方法の説明図
である。
１・・・コア、２・・・クラッド、３・・・シリコン樹
脂、４・・・ナイロン、５・・・薄肉プラスチック−次
被慣、ダ・・・第１層被覆、ｓＬ／・・・第２層被筒、
６・・・プラスチツクニ次ｍＷ、１１・・・光フアイバ
プリフォーム、１２・・・線引炉、１３１１３’ １１
３″・・・スプレーノズル、１４．１４’。
１４ｑ・・・硬化炉、１５．１５’・・・絞りダイス、
１６・・・軟化融着 □炉、１６・・・加熱炉、１７・
・・二次被償コーティングダイ （ス、１８・・・硬化
炉、１９・・・巻取機。
Ｎ 〜
エ規化報１室ｔ（４）
第７図 第８図FIG. 1 is a cross-sectional view of a multi-core fiber, FIG. 2 is a cross-sectional view of a punched fiber, FIG. 3 is a cross-sectional view of a multi-core optical fiber, and FIG. 4 is an embodiment of a multi-core optical fiber of the present invention. (A) is a cross-sectional view of a concentric multi-core optical fiber, (B) is a cross-sectional view of a flat core optical fiber, and FIG. 5 is a side cross-sectional view of the structure of the multi-core optical fiber of the present invention. Fig. 6 is a graph of the measurement results of the relationship between the amount of axial slippage and splicing efficiency during fusion splicing of optical fibers, and Figs. 7-1 and 8 are explanatory diagrams of different manufacturing methods of the multi-core optical fiber of the present invention. . DESCRIPTION OF SYMBOLS 1...Core, 2...Clad, 3...Silicon resin, 4...Nylon, 5...Thin plastic-secondary wear, D...First layer coating, sL/... second layer jacket,
6... Plastic second order mW, 11... Optical fiber preform, 12... Drawing furnace, 13113' 11
3″... Spray nozzle, 14.14'. 14q... Hardening furnace, 15.15'... Drawing die,
16...Softening fusion □Furnace, 16...Heating furnace, 17.
... Secondary coating die (S, 18... Hardening furnace, 19... Winding machine.
Claims (1)
れた複数本のがラスファイバが互いに接着してなること
を特徴とする多心光ファイバ。 ２、特許請求の範囲第１項においてガラスファイバが２
層以上の輿梱プラスチックで被覆され、外層のプラスチ
ックで互いに接着してなることを特徴とする多心光ファ
イバ。 ３ 厚さがコア半径のη以下のプラスチックで被覆され
たー数本のガラスファイバが互いに接着してなる多心光
ファイバを製造するに、複ｉ本のガラスファイバを互い
に接触させずに同時に腺引きし、そのま＼直ちに他の物
体に接触する前に厚さがコア径のｌｈ ＠以下のコーテ
ィングを施した後、さらにそのま＼直ちに束ねて互いに
接着することを特徴とする多心光ファイバの製造方法。[Scope of Claims] 1. A multi-core optical fiber comprising a plurality of lath fibers coated with plastic having a thickness of 5 or less of the core radius and bonded to each other. 2. In claim 1, the glass fiber is 2.
A multi-core optical fiber characterized by being coated with more than one layer of plastic and bonded to each other with outer plastic layers. 3. To manufacture a multi-core optical fiber consisting of several glass fibers coated with plastic with a thickness less than the core radius η and bonded to each other, it is necessary to simultaneously bond multiple i glass fibers without contacting each other. A multicore optical fiber characterized in that it is coated with a coating having a thickness less than lh of the core diameter before it is pulled out and immediately comes into contact with another object, and then it is immediately bundled and bonded to each other. manufacturing method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59011425A JPS60154204A (en) | 1984-01-24 | 1984-01-24 | Multicore optical fiber and its manufacture |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59011425A JPS60154204A (en) | 1984-01-24 | 1984-01-24 | Multicore optical fiber and its manufacture |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS60154204A true JPS60154204A (en) | 1985-08-13 |
Family
ID=11777704
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP59011425A Pending JPS60154204A (en) | 1984-01-24 | 1984-01-24 | Multicore optical fiber and its manufacture |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS60154204A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4828349A (en) * | 1986-08-05 | 1989-05-09 | Sumitomo Electric Industries, Ltd. | Multicore optical fiber |
| FR2684192A1 (en) * | 1991-11-26 | 1993-05-28 | Fort Fibres Optiques Rech Tec | MULTI-FIBER OPTICAL CABLE, AND ITS MANUFACTURING METHOD. |
| US5761361A (en) * | 1995-05-10 | 1998-06-02 | Siemens Aktiengesellschaft | Elongated optical transmission element |
| KR20000047141A (en) * | 1998-12-31 | 2000-07-25 | 강병호 | Optical cable |
| US6538045B1 (en) | 1999-12-23 | 2003-03-25 | Dsm N.V. | Optical fiber coating compositions containing secondary or tertiary amino silicone-containing additive |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5915907A (en) * | 1982-07-19 | 1984-01-27 | Nippon Telegr & Teleph Corp <Ntt> | Production of plural-cored optical fiber bundle |
-
1984
- 1984-01-24 JP JP59011425A patent/JPS60154204A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5915907A (en) * | 1982-07-19 | 1984-01-27 | Nippon Telegr & Teleph Corp <Ntt> | Production of plural-cored optical fiber bundle |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4828349A (en) * | 1986-08-05 | 1989-05-09 | Sumitomo Electric Industries, Ltd. | Multicore optical fiber |
| FR2684192A1 (en) * | 1991-11-26 | 1993-05-28 | Fort Fibres Optiques Rech Tec | MULTI-FIBER OPTICAL CABLE, AND ITS MANUFACTURING METHOD. |
| US5761361A (en) * | 1995-05-10 | 1998-06-02 | Siemens Aktiengesellschaft | Elongated optical transmission element |
| KR20000047141A (en) * | 1998-12-31 | 2000-07-25 | 강병호 | Optical cable |
| US6538045B1 (en) | 1999-12-23 | 2003-03-25 | Dsm N.V. | Optical fiber coating compositions containing secondary or tertiary amino silicone-containing additive |
| US7041712B2 (en) | 1999-12-23 | 2006-05-09 | Dsm Ip Assets B.V. | Optical fiber coating compositions containing secondary or tertiary amino silicone-containing additive |
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