JPH0236535B2 - - Google Patents
Info
- Publication number
- JPH0236535B2 JPH0236535B2 JP56056764A JP5676481A JPH0236535B2 JP H0236535 B2 JPH0236535 B2 JP H0236535B2 JP 56056764 A JP56056764 A JP 56056764A JP 5676481 A JP5676481 A JP 5676481A JP H0236535 B2 JPH0236535 B2 JP H0236535B2
- Authority
- JP
- Japan
- Prior art keywords
- base material
- glass
- porous
- core
- stress
- 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 - Lifetime
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B37/00—Manufacture or treatment of flakes, fibres, or filaments from softened glass, minerals, or slags
- C03B37/01—Manufacture of glass fibres or filaments
- C03B37/012—Manufacture of preforms for drawing fibres or filaments
- C03B37/014—Manufacture of preforms for drawing fibres or filaments made entirely or partially by chemical means, e.g. vapour phase deposition of bulk porous glass either by outside vapour deposition [OVD], or by outside vapour phase oxidation [OVPO] or by vapour axial deposition [VAD]
- C03B37/01413—Reactant delivery systems
- C03B37/0142—Reactant deposition burners
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B2201/00—Type of glass produced
- C03B2201/06—Doped silica-based glasses
- C03B2201/08—Doped silica-based glasses doped with boron or fluorine or other refractive index decreasing dopant
- C03B2201/10—Doped silica-based glasses doped with boron or fluorine or other refractive index decreasing dopant doped with boron
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B2201/00—Type of glass produced
- C03B2201/06—Doped silica-based glasses
- C03B2201/30—Doped silica-based glasses doped with metals, e.g. Ga, Sn, Sb, Pb or Bi
- C03B2201/31—Doped silica-based glasses doped with metals, e.g. Ga, Sn, Sb, Pb or Bi doped with germanium
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B2201/00—Type of glass produced
- C03B2201/06—Doped silica-based glasses
- C03B2201/30—Doped silica-based glasses doped with metals, e.g. Ga, Sn, Sb, Pb or Bi
- C03B2201/40—Doped silica-based glasses doped with metals, e.g. Ga, Sn, Sb, Pb or Bi doped with transition metals other than rare earth metals, e.g. Zr, Nb, Ta or Zn
- C03B2201/42—Doped silica-based glasses doped with metals, e.g. Ga, Sn, Sb, Pb or Bi doped with transition metals other than rare earth metals, e.g. Zr, Nb, Ta or Zn doped with titanium
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B2203/00—Fibre product details, e.g. structure, shape
- C03B2203/30—Polarisation maintaining [PM], i.e. birefringent products, e.g. with elliptical core, by use of stress rods, "PANDA" type fibres
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B2207/00—Glass deposition burners
- C03B2207/50—Multiple burner arrangements
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Optical Fibers, Optical Fiber Cores, And Optical Fiber Bundles (AREA)
- Manufacture, Treatment Of Glass Fibers (AREA)
Description
【発明の詳細な説明】
本発明は低損失特性を有し、かつ偏光保持性に
優れた単一モード光フアイバの製造方法に関す
る。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a single mode optical fiber having low loss characteristics and excellent polarization retention.
従来、偏光特性の優れた単一偏波単一モード光
アイバ用母材の製造方法としては、IEEE、
Journal of Quantum Electionics、Vol.QE−
17、No.１、p.15（1981）に報告されている
「Polarization in Optical Fibers」なる題名の論
文に見られるように、MCVD法（化学気相堆積
法）で製造された第１図ａに示すコア用丸棒状透
明ガラス母材１を、第１図ｂに示すように、軸に
平行な相向かう両面を研磨し、両面研磨母材２を
作製した後、コア径の大きさを調節するため、第
１図ｃに示すように、該研磨母材２にジヤケツト
用ガラス管３をかぶせ、炭素抵抗加熱炉等で線引
きする方法が一般的であつたが、この方法ではコ
ア形状が楕円になり、フアイバ間の接続上の問題
点があつた。 Conventionally, methods for producing base materials for single-polarization single-mode optical fibers with excellent polarization properties include IEEE,
Journal of Quantum Electionics, Vol.QE−
17, No. 1, p. 15 (1981), Fig. 1a manufactured by the MCVD method (chemical vapor deposition). As shown in FIG. 1b, the round bar-shaped transparent glass base material 1 for the core is polished on both sides parallel to the axis to produce a double-sided polished base material 2, and then the core diameter is adjusted. In order to do this, the common method was to cover the polished base material 2 with a glass tube 3 for jacket and draw it in a carbon resistance heating furnace, etc., as shown in FIG. This caused problems in connection between fibers.
さらにこの方法では、コア形状を楕円率ｅ＝
ａ−ｂ／ａ＋ｂ（ａ：長径、ｂ：短径）が40％の場合で
複屈折性が10-5程度の大きさしか得られず、必ず
しも十分ではなかつた。 Furthermore, in this method, the core shape has an ellipticity e=
When a-b/a+b (a: major axis, b: minor axis) is 40%, a birefringence of only about 10 -5 can be obtained, which is not necessarily sufficient.
本発明はこれらの欠点を除くため、コア用ガラ
ス部の形状を真円に保つたまま、クラツド部のガ
ラス組成を非軸対称にすることにより、コア内部
に応力分布を持つた光フアイバを製造する方法を
提供しようとするものである。以下、図面により
本発明を詳細に説明する。 In order to eliminate these drawbacks, the present invention manufactures an optical fiber with stress distribution inside the core by making the glass composition of the cladding part non-axisymmetric while keeping the shape of the core glass part perfectly circular. The aim is to provide a method to do so. Hereinafter, the present invention will be explained in detail with reference to the drawings.
実施例 １
多孔質母材の段階で応力付与構造とする方法
第２図〜第５図は本発明の一実施例を示し、４
はコア用トーチ、５および６は合成クラツド用ト
ーチ、７は反応球、８は排気部、９は支持棒、１
０は回転部、１１はコア用多孔質母材、１２は合
成クラツド用母材である。Example 1 Method for creating a stress-applying structure at the stage of porous base material Figures 2 to 5 show an example of the present invention, and 4
1 is a torch for the core, 5 and 6 are torches for synthetic cladding, 7 is a reaction bulb, 8 is an exhaust part, 9 is a support rod, 1
0 is a rotating part, 11 is a porous base material for the core, and 12 is a base material for the synthetic cladding.
本発明において初めに、コア用多孔質母材およ
び合成クラツド用多孔質母材を形成するため、回
転部１０によつて5rpmで回転する支持棒９の上
にコア用トーチ４を通して６／minの酸素ガ
ス、４／minの水素ガスとともに、Arガスで
輸送される100c.c.／minのSiCl4ガス、10c.c.／min
のGeCl4ガス、５c.c.／minのPOCl3ガスを流し、
コア用トーチ４の前面でH2−O2炎を形成し、火
炎内でSiCl4、GeCl4、POCl3を火炎加水分解反応
させてガラス微粒子を形成し、まずコア用多孔質
母材１１を合成する。 In the present invention, first, in order to form a porous base material for the core and a porous base material for the synthetic cladding, the torch 4 for the core is passed over the support rod 9 which is rotated at 5 rpm by the rotating part 10 at a rate of 6 rpm. 100 c.c./min of SiCl 4 gas transported by Ar gas, 10 c.c./min with oxygen gas, 4 /min of hydrogen gas
of GeCl 4 gas, 5 c.c./min of POCl 3 gas,
A H 2 -O 2 flame is formed in front of the core torch 4, and SiCl 4 , GeCl 4 , and POCl 3 are subjected to a flame hydrolysis reaction in the flame to form glass particles. Synthesize.
支持棒９はコア用多孔質母材１１の成長速度に
合わせて上方に引き上げ、成長端は一定位置に保
たれる。またコア用多孔質母材１１の成長に従
い、該側面に合成クラツド用トーチ５および６か
ら流す５／minのO2ガス、４／minのH2ガ
ス、Arガスで輸送される200c.c.／minのSiCl4ガス
を、同様に火炎加水分解反応させて、合成クラツ
ド用多孔質母材１２を形成する。 The support rod 9 is pulled upward in accordance with the growth rate of the core porous base material 11, and the growth end is kept at a constant position. In addition , as the porous base material 11 for the core grows, 200 c.c. /min of SiCl 4 gas is similarly subjected to a flame hydrolysis reaction to form the porous base material 12 for the synthetic cladding.
続いて該母材を炭素抵抗炉内に入れ、1200℃の
温度で１時間、熱処理を施し、半焼結させる。 Subsequently, the base material is placed in a carbon resistance furnace and heat-treated at a temperature of 1200° C. for 1 hour to semi-sinter it.
次に第３図ａ，ｂに示すように、該半焼結多孔
質母材１３の外側に応力付与用多孔質ガラスを堆
積させる。１４，１５，１６，１７は応力付与用
多孔質ガラス用トーチ、１８は回転部、１９は
SiO2・B2O3・GeO2から成る多孔質ガラス、２０
はSiO2・TiO2から成る多孔質ガラス、２１は排
気部、２２は反応球、２３は支持棒である。 Next, as shown in FIGS. 3a and 3b, stress-applying porous glass is deposited on the outside of the semi-sintered porous base material 13. 14, 15, 16, 17 are stress-applying porous glass torches, 18 is a rotating part, and 19 is a
Porous glass consisting of SiO 2・B 2 O 3・GeO 2 , 20
2 is a porous glass made of SiO 2 and TiO 2 , 21 is an exhaust section, 22 is a reaction ball, and 23 is a support rod.
これを動作させるには、トーチ１４，１５から
H2、O2、SiCl4、BBr3、GeCl4ガスを流し、
SiO2・B2O3・GeO2から成る多孔質ガラス１９を
半焼結多孔質母材１３の側面に母材の軸と平行に
堆積させる。トーチ１６，１７によつてH2、O2、
SiCl4、TiCl4を流し、同様にSiO2・TiO2から成
る多孔質ガラスを前記ガラスと直角な角度に堆積
させる。応力付与用多孔質ガラスの成長に伴い、
支持棒２３は回転させずに、成長端が一定位置に
保たれるように上方に移動させる。このようにし
て得た多孔質ガラスを焼結、透明ガラス化させた
ものを所望の太さになるように延伸加工した後、
第４図に示すようにコア径が単一モード条件を満
たすようにジヤケツト用ガラス管２４をかぶせ、
線引きして、光フアイバを得る。第４図におい
て、２５はコア、２６は合成クラツド、２７，２
８は応力付与用クラツドである。 To make this work, start with torches 14 and 15.
Flow H 2 , O 2 , SiCl 4 , BBr 3 , GeCl 4 gas,
A porous glass 19 made of SiO 2 .B 2 O 3 .GeO 2 is deposited on the side surface of the semi-sintered porous base material 13 parallel to the axis of the base material. H 2 , O 2 ,
SiCl 4 and TiCl 4 are poured, and porous glass made of SiO 2 and TiO 2 is similarly deposited at a right angle to the glass. With the growth of porous glass for applying stress,
The support rod 23 is not rotated but is moved upward so that the growth end is kept at a constant position. The porous glass thus obtained is sintered and made into transparent glass, which is then stretched to the desired thickness.
As shown in FIG. 4, cover the jacket with a glass tube 24 so that the core diameter satisfies the single mode condition.
Draw to obtain optical fiber. In Fig. 4, 25 is the core, 26 is the synthetic cladding, 27, 2
8 is a stress applying clad.
第５図ａは光フアイバの断面を示し、第５図ｂ
および第５図ｃはそれぞれｘ軸、ｙ軸方向の断面
の熱膨脹係数の分布を示したものである。 Figure 5a shows a cross section of the optical fiber, Figure 5b
FIG. 5c shows the distribution of the coefficient of thermal expansion in the cross section in the x-axis and y-axis directions, respectively.
第５図ａにおいて２６は合成クラツド用、２７
はB2O3・SiO2から成る応力付与用ガラス、２８
はTiO2・SiO2から成る応力付与用ガラス、２９
はジヤケツトガラスである。 In Figure 5a, 26 is for synthetic cladding, 27
is a stress-applying glass composed of B 2 O 3 and SiO 2 , 28
is a stress-applying glass made of TiO 2 and SiO 2 , 29
is jacket glass.
SiO2、GeO2・SiO2、B2O3・SiO2・TiO2・
SiO2の熱膨脹係数（参考文献：Martin Emery
Nordberg；U.S.Patent Specifications 538、
891、1941）をそれぞれα0、α1、α2、α3とすると、
α1＞α0
α2＞α0
α3＜α0α0＝5.5×10-7℃-1
α1＝9.4×10-7℃-1
α2＝11.0×10-7℃-1
α3＝0.1×10-7℃-1
であるので、ｘ方向、ｙ方向の熱膨脹係数の分布
は第５図ｂおよび第５図ｃに示すようになる。直
交する２方向の熱膨脹係数の分布が異なることか
ら、フアイバ内の応力分布は非軸対称となり、そ
の結果として複屈折性が得られる。このようにし
て得られた複屈折性は５×10-4の大きさに達し
た。また0.5dB／Km、50Kmの低損失、長尺化も可
能となる。 SiO 2 , GeO 2・SiO 2 , B 2 O 3・SiO 2・TiO 2・
Thermal expansion coefficient of SiO 2 (Reference: Martin Emery
Nordberg; US Patent Specifications 538;
891, 1941) are α 0 , α 1 , α 2 , α 3 respectively, then α 1 > α 0 α 2 > α 0 α 3 <α 0 α 0 =5.5×10 -7 ℃ -1 α 1 =9.4 ×10 -7 °C -1 α 2 = 11.0 × 10 -7 °C -1 α 3 = 0.1 × 10 -7 °C -1 , so the distribution of the coefficient of thermal expansion in the x and y directions is as shown in Figure 5b and Figure 5b. The result is as shown in Figure 5c. Due to the different distribution of thermal expansion coefficients in two orthogonal directions, the stress distribution within the fiber is non-axisymmetric, resulting in birefringence. The birefringence thus obtained reached a magnitude of 5×10 −4 . It also enables low loss of 0.5 dB/Km, 50 km, and long length.
実施例 ２
応力付与用ガラス部の形状について
応力付与用ガラスに研磨加工を施すことによ
り、応力付与用ガラス部を第６図ａ，ｂ，ｃ，ｄ
に示すように、種々の形状にすることが可能であ
つた。Example 2 About the shape of the stress-applying glass part By polishing the stress-applying glass part, the stress-applying glass part is shaped like the shapes shown in Fig. 6 a, b, c, and d.
As shown in the figure, it was possible to make it into various shapes.
なお本発明の単一モード光フアイバの製造方法
において、コア中心軸に対して、相対向する１組
の応力付与用ガラスの熱膨脹係数がSiO2より大
きく、他方の１組の応力付与用ガラスの熱膨脹係
数がSiO2より小さくなるように、応力付与用ガ
ラス原料を選定することもできる。 In the method for manufacturing a single-mode optical fiber of the present invention, one set of stress-applying glasses facing opposite to each other with respect to the core central axis has a coefficient of thermal expansion larger than SiO 2 , and the other pair of stress-applying glasses has a thermal expansion coefficient of The stress-applying glass raw material can also be selected so that its coefficient of thermal expansion is smaller than that of SiO 2 .
また本発明の単一モード光フアイバの製造方法
において、コア用ガラスとして、GeO2・SiO2、
P2O5・SiO2、GeO2・P2O5・SiO2のいずれか
一つとなるように、コア用ガラス原料を選定し、
２組の応力付与用ガラスの一方をTiO2・SiO2、
他方をB2O3・SiO2、B2O3・GeO2・SiO2、
GeO2・Ｆ・SiO2、B2O3・P2O5・SiO2、
Ｆ・P2O5・SiO2のいずれか一つとなるように、
応力付与用ガラス原料を選定することもできる。 Furthermore, in the method for manufacturing a single mode optical fiber of the present invention, GeO 2 ·SiO 2 , GeO 2 ·SiO 2 ,
Select the glass raw material for the core to be one of P 2 O 5 · SiO 2 and GeO 2 · P 2 O 5 · SiO 2 ,
One of the two sets of stress-applying glasses is made of TiO 2 /SiO 2 ,
The other side is B 2 O 3 · SiO 2 , B 2 O 3 · GeO 2 · SiO 2 ,
GeO2 ・F・SiO2 , B2O3・P2O5・SiO2 ,
So that it is one of F・P 2 O 5・SiO 2 ,
It is also possible to select a glass raw material for applying stress.
以上説明したように、本発明の製造方法によれ
ば、コア形状を円形とし、対称性を保つたまま、
従来構造のフアイバより大きな複屈折性を有し、
長尺、低損失で、かつ接続の容易な単一モード光
フアイバが得られるので、コヒーレント伝送が可
能となるという利点がある。 As explained above, according to the manufacturing method of the present invention, the core shape is made circular, and while maintaining symmetry,
It has greater birefringence than conventionally structured fibers,
Since a long, low-loss, and easily connectable single-mode optical fiber can be obtained, there is an advantage that coherent transmission is possible.
第１図は従来の偏光特性を有する単一モード光
フアイバを製造する方法の説明図、第２図〜第５
図は本発明の一実施例の説明図、第６図は本発明
の他の実施例の説明図である。
１……コア用丸棒状透明ガラス母材、２……両
面研磨母材、３……ジヤケツト用ガラス管、４…
…コア用トーチ、５，６……合成クラツド用トー
チ、７……反応球、８……排気部、９……支持
棒、１０……回転部、１１……コア用多孔質母
材、１２……合成クラツド用母材、１３……半焼
結多孔質母材、１４，１５，１６，１７……応力
付与用多孔質母材用トーチ、１８……回転部、１
９……SiO2・B2O3・GeO2から成る多孔質ガラ
ス、２０……SiO2・TiO2から成る多孔質ガラス、
２１……排気部、２２……反応球、２３……支持
棒、２４……ジヤケツト用ガラス管、２５……コ
ア、２６……合成クラツド、２７，２８……応力
付与用クラツド、２９……クラツド。
Figure 1 is an explanatory diagram of a conventional method for manufacturing a single mode optical fiber with polarization characteristics, Figures 2 to 5
The figure is an explanatory diagram of one embodiment of the present invention, and FIG. 6 is an explanatory diagram of another embodiment of the present invention. 1...Round bar-shaped transparent glass base material for core, 2...Double-sided polished base material, 3...Glass tube for jacket, 4...
... Torch for core, 5, 6 ... Torch for synthetic cladding, 7 ... Reaction sphere, 8 ... Exhaust part, 9 ... Support rod, 10 ... Rotating part, 11 ... Porous base material for core, 12 ... Base material for synthetic cladding, 13... Semi-sintered porous base material, 14, 15, 16, 17... Torch for porous base material for applying stress, 18... Rotating part, 1
9... Porous glass consisting of SiO 2 · B 2 O 3 · GeO 2 , 20... Porous glass consisting of SiO 2 · TiO 2 ,
21...Exhaust part, 22...Reaction bulb, 23...Support rod, 24...Glass tube for jacket, 25...Core, 26...Synthetic clad, 27, 28...Stress applying clad, 29... Cratsud.
Claims (1)
そのまわりにクラツド用多孔質ガラスを堆積さ
せ、これを仮焼結させて半焼結多孔質母材とし、
該半焼結多孔質母材の中心軸を含み互いに直交す
る二つの面により区画される四つの部分の側曲面
上に、熱膨脹係数の異なる２種の応力付与用多孔
質ガラスを、交互にそれぞれ前記中心軸に対して
対称的に堆積させ、全体を焼結、透明ガラス化さ
せた母材を、必要に応じてジヤケツト用ガラス管
でジヤケツトし、線引きすることを特徴とする単
一モード光フアイバの製造方法。1 Depositing porous glass for the core and porous glass for the cladding around it by the VAD method, and pre-sintering this to make a semi-sintered porous base material,
Two types of stress-applying porous glasses having different coefficients of thermal expansion are alternately placed on the side curved surfaces of four portions defined by two mutually orthogonal surfaces including the central axis of the semi-sintered porous base material. A single mode optical fiber characterized in that the base material is deposited symmetrically with respect to the central axis, the whole is sintered and made into transparent glass, and the base material is jacketed with a jacket glass tube as necessary and drawn. Production method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP56056764A JPS57170835A (en) | 1981-04-15 | 1981-04-15 | Manufacture of single-mode optical fiber |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP56056764A JPS57170835A (en) | 1981-04-15 | 1981-04-15 | Manufacture of single-mode optical fiber |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS57170835A JPS57170835A (en) | 1982-10-21 |
| JPH0236535B2 true JPH0236535B2 (en) | 1990-08-17 |
Family
ID=13036556
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP56056764A Granted JPS57170835A (en) | 1981-04-15 | 1981-04-15 | Manufacture of single-mode optical fiber |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS57170835A (en) |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS60173505A (en) * | 1984-02-07 | 1985-09-06 | Nippon Telegr & Teleph Corp <Ntt> | Optical fiber for maintaining polarized wave |
| JPS60260430A (en) * | 1984-06-04 | 1985-12-23 | Sumitomo Electric Ind Ltd | Manufacture of base material for optical fiber containing fluorine in clad part |
| JPS6333710A (en) * | 1986-07-28 | 1988-02-13 | Nippon Telegr & Teleph Corp <Ntt> | Quartz optical waveguide with stress applying part |
| JPH0646245B2 (en) * | 1986-08-11 | 1994-06-15 | 日本電信電話株式会社 | Single-mode optical waveguide with groove for stress relief |
| JP2519959Y2 (en) * | 1988-10-21 | 1996-12-11 | 株式会社フジクラ | Polarization-maintaining optical fiber |
| US5043002A (en) * | 1990-08-16 | 1991-08-27 | Corning Incorporated | Method of making fused silica by decomposing siloxanes |
| US5296012A (en) * | 1992-12-28 | 1994-03-22 | Corning Incorporated | Method of making optical waveguide preforms |
| KR100274807B1 (en) | 1998-06-24 | 2000-12-15 | 김효근 | Optical fiber and bragg grating filter using the same |
-
1981
- 1981-04-15 JP JP56056764A patent/JPS57170835A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS57170835A (en) | 1982-10-21 |
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