JPH038743A - Optical fiber preform and preparation thereof - Google Patents
Optical fiber preform and preparation thereofInfo
- Publication number
- JPH038743A JPH038743A JP14326989A JP14326989A JPH038743A JP H038743 A JPH038743 A JP H038743A JP 14326989 A JP14326989 A JP 14326989A JP 14326989 A JP14326989 A JP 14326989A JP H038743 A JPH038743 A JP H038743A
- Authority
- JP
- Japan
- Prior art keywords
- base material
- fluorine
- optical fiber
- porous glass
- fiber preform
- 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.)
- Granted
Links
- 239000013307 optical fiber Substances 0.000 title claims abstract description 38
- 238000002360 preparation method Methods 0.000 title abstract 2
- 239000000463 material Substances 0.000 claims abstract description 63
- 229910052731 fluorine Inorganic materials 0.000 claims abstract description 48
- 239000011737 fluorine Substances 0.000 claims abstract description 48
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 claims abstract description 44
- 239000005373 porous glass Substances 0.000 claims abstract description 35
- 239000011521 glass Substances 0.000 claims abstract description 16
- 150000003377 silicon compounds Chemical class 0.000 claims abstract description 7
- 238000000034 method Methods 0.000 claims description 23
- 238000005253 cladding Methods 0.000 claims description 15
- 150000002222 fluorine compounds Chemical class 0.000 claims description 13
- 239000001307 helium Substances 0.000 claims description 8
- 229910052734 helium Inorganic materials 0.000 claims description 8
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 claims description 8
- 238000004519 manufacturing process Methods 0.000 claims description 8
- 239000002245 particle Substances 0.000 claims description 7
- 230000003301 hydrolyzing effect Effects 0.000 claims description 3
- 239000011159 matrix material Substances 0.000 claims 1
- 230000007847 structural defect Effects 0.000 abstract description 31
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 abstract description 25
- 238000005245 sintering Methods 0.000 abstract description 13
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 abstract description 11
- 230000005540 biological transmission Effects 0.000 abstract description 10
- 239000001257 hydrogen Substances 0.000 abstract description 7
- 229910052739 hydrogen Inorganic materials 0.000 abstract description 7
- 238000010438 heat treatment Methods 0.000 abstract description 3
- 230000007547 defect Effects 0.000 abstract description 2
- 239000010419 fine particle Substances 0.000 abstract description 2
- VZGDMQKNWNREIO-UHFFFAOYSA-N tetrachloromethane Chemical compound ClC(Cl)(Cl)Cl VZGDMQKNWNREIO-UHFFFAOYSA-N 0.000 abstract 2
- ZZUFCTLCJUWOSV-UHFFFAOYSA-N furosemide Chemical compound C1=C(Cl)C(S(=O)(=O)N)=CC(C(O)=O)=C1NCC1=CC=CO1 ZZUFCTLCJUWOSV-UHFFFAOYSA-N 0.000 abstract 1
- 239000000835 fiber Substances 0.000 description 12
- 238000010521 absorption reaction Methods 0.000 description 11
- 239000007789 gas Substances 0.000 description 10
- 239000010453 quartz Substances 0.000 description 9
- 238000009792 diffusion process Methods 0.000 description 7
- 238000009826 distribution Methods 0.000 description 7
- 230000007062 hydrolysis Effects 0.000 description 6
- 238000006460 hydrolysis reaction Methods 0.000 description 6
- ABTOQLMXBSRXSM-UHFFFAOYSA-N silicon tetrafluoride Chemical compound F[Si](F)(F)F ABTOQLMXBSRXSM-UHFFFAOYSA-N 0.000 description 6
- 230000007423 decrease Effects 0.000 description 5
- 238000006243 chemical reaction Methods 0.000 description 4
- 230000018044 dehydration Effects 0.000 description 4
- 238000006297 dehydration reaction Methods 0.000 description 4
- 238000000151 deposition Methods 0.000 description 4
- 150000002221 fluorine Chemical class 0.000 description 4
- 239000011148 porous material Substances 0.000 description 4
- 239000010703 silicon Substances 0.000 description 4
- 229910052710 silicon Inorganic materials 0.000 description 4
- 238000004017 vitrification Methods 0.000 description 4
- 230000015572 biosynthetic process Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 3
- 238000009987 spinning Methods 0.000 description 3
- VXEGSRKPIUDPQT-UHFFFAOYSA-N 4-[4-(4-methoxyphenyl)piperazin-1-yl]aniline Chemical compound C1=CC(OC)=CC=C1N1CCN(C=2C=CC(N)=CC=2)CC1 VXEGSRKPIUDPQT-UHFFFAOYSA-N 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- KZBUYRJDOAKODT-UHFFFAOYSA-N Chlorine Chemical compound ClCl KZBUYRJDOAKODT-UHFFFAOYSA-N 0.000 description 2
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 239000000460 chlorine Substances 0.000 description 2
- 229910052801 chlorine Inorganic materials 0.000 description 2
- 150000001805 chlorine compounds Chemical class 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 239000002019 doping agent Substances 0.000 description 2
- OJCDKHXKHLJDOT-UHFFFAOYSA-N fluoro hypofluorite;silicon Chemical compound [Si].FOF OJCDKHXKHLJDOT-UHFFFAOYSA-N 0.000 description 2
- 229910052732 germanium Inorganic materials 0.000 description 2
- GNPVGFCGXDBREM-UHFFFAOYSA-N germanium atom Chemical compound [Ge] GNPVGFCGXDBREM-UHFFFAOYSA-N 0.000 description 2
- 230000009257 reactivity Effects 0.000 description 2
- 239000005049 silicon tetrachloride Substances 0.000 description 2
- 239000007858 starting material Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 229910052717 sulfur Inorganic materials 0.000 description 2
- 239000011593 sulfur Substances 0.000 description 2
- SFZCNBIFKDRMGX-UHFFFAOYSA-N sulfur hexafluoride Chemical compound FS(F)(F)(F)(F)F SFZCNBIFKDRMGX-UHFFFAOYSA-N 0.000 description 2
- TXEYQDLBPFQVAA-UHFFFAOYSA-N tetrafluoromethane Chemical compound FC(F)(F)F TXEYQDLBPFQVAA-UHFFFAOYSA-N 0.000 description 2
- 101000856246 Arabidopsis thaliana Cleavage stimulation factor subunit 77 Proteins 0.000 description 1
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 description 1
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical compound F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 description 1
- 101000716729 Homo sapiens Kit ligand Proteins 0.000 description 1
- 102100020880 Kit ligand Human genes 0.000 description 1
- 229910004014 SiF4 Inorganic materials 0.000 description 1
- QPAXMPYBNSHKAK-UHFFFAOYSA-N chloro(difluoro)methane Chemical compound F[C](F)Cl QPAXMPYBNSHKAK-UHFFFAOYSA-N 0.000 description 1
- KYKAJFCTULSVSH-UHFFFAOYSA-N chloro(fluoro)methane Chemical compound F[C]Cl KYKAJFCTULSVSH-UHFFFAOYSA-N 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 150000002431 hydrogen Chemical class 0.000 description 1
- 229910000040 hydrogen fluoride Inorganic materials 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
- 229960000909 sulfur hexafluoride Drugs 0.000 description 1
- OBTWBSRJZRCYQV-UHFFFAOYSA-N sulfuryl difluoride Chemical compound FS(F)(=O)=O OBTWBSRJZRCYQV-UHFFFAOYSA-N 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
- LSJNBGSOIVSBBR-UHFFFAOYSA-N thionyl fluoride Chemical compound FS(F)=O LSJNBGSOIVSBBR-UHFFFAOYSA-N 0.000 description 1
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]
- C03B37/01446—Thermal after-treatment of preforms, e.g. dehydrating, consolidating, sintering
-
- 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
- C03B2201/12—Doped silica-based glasses doped with boron or fluorine or other refractive index decreasing dopant doped with fluorine
Abstract
Description
【発明の詳細な説明】
［産業上の利用分野］
本発明は光ファイバ用母材、特には伝送損失に関係する
構造欠陥が極めて少なく、化学処理、熱処理、水素ｆｉ
埋に対して伝送損失増をもたらさない光ファイバ用母材
およびその製造方法に関するものである。[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a base material for optical fibers, which has extremely few structural defects related to transmission loss, and which is suitable for chemical treatment, heat treatment, and hydrogen fibre.
The present invention relates to an optical fiber base material that does not cause an increase in transmission loss compared to fibers, and a method for manufacturing the same.
［従来の技術］
光ファイバ用母材については所望の屈折率分布を得るた
めにコア部にゲルマニウムをドープし、クラッド部を純
石英からなるものとしたもの、コア部を純石英からなる
ものとし、クラッド部にフッ素をドープしたものなどが
知られており、これらにより製造された光ファイバーは
コア部またはクラッド部に構造欠陥が存在し伝送特性が
劣化し、ファイバ紡系条件や水素処理などによって構造
欠陥に関係する吸収損失増が生じ、光伝送に使用する１
、３μｍ、 １．５５ａｍ帯の損失増がもたらされるこ
とも知られている。[Prior art] In order to obtain a desired refractive index distribution, the base material for optical fiber is doped with germanium in the core, the cladding is made of pure quartz, and the core is made of pure quartz. Optical fibers manufactured using these methods have structural defects in the core or cladding, resulting in deterioration in transmission characteristics, and fiber spinning conditions or hydrogen treatment may cause structural defects. Increased absorption loss related to defects occurs, and 1
It is also known that loss increases in the , 3 μm, and 1.55 am bands.
また、構造欠陥を埋めるドープ剤の添加も種々検討され
ており、フッ素をドープした石英ガラスは化学的に安定
であり、耐熱、耐水素特性にすぐれていることが知られ
ているが、このコア部、クラッド部に対するフッ素のド
ープについては上記したけい素化合物の気相加水分解時
にフッ素化合物を添加する方法、多孔質ガラス母材の焼
結ガラス工程でフッ素化合物を添加する方法、この焼結
時における１、０００〜１，２００℃の温度下における
脱水工程でフッ素化合物を添加する方法などが知られて
いる。In addition, various studies are being conducted on the addition of dopants to fill in structural defects, and it is known that fluorine-doped silica glass is chemically stable and has excellent heat and hydrogen resistance properties. Regarding the doping of fluorine into the cladding part, there are two methods: a method of adding a fluorine compound during gas phase hydrolysis of a silicon compound, a method of adding a fluorine compound during the glass sintering process of a porous glass base material, and a method of adding a fluorine compound during the sintering process of a porous glass base material. A method is known in which a fluorine compound is added during a dehydration step at a temperature of 1,000 to 1,200°C.
［発明によって解決されるべき課題］
しかし、このフッ素ドープをけい素化合物の気相加水分
解時に行なうとシリカ微粒子の生成過程においてフッ素
がドープされる反応と同時に構造欠陥が生じるために、
この多孔質ガラス母材製造時にフッ素ドープによって構
造欠陥を効果的に消滅させることはできない。また、多
孔質ガラス母材の焼結ガラス工程でフッ素化合物を添加
すると透明ガラス化が高温で行なわれるためにフッ素の
拡散によってフッ素ドープ反応は非常に速く行なわれる
が、多孔質ガラス母材の収縮も同時に起るためにフッ素
化合物を微量添加した場合にこのフッ素ドープは母材の
周辺部で多く、中心部で少なくなる傾向があるし、凸状
の屈折率分布が形成されると同時に母材中心部に構造欠
陥が残存するという欠点があり、さらに焼結時の脱水工
程でフッ素ドープをするときにはフッ素のドープ反応が
フッ素の拡散より速いのでフッ素ドープされた石英母材
のガラス化温度が下がって多孔質ガラス母材が収縮する
ために、微量のフッ素で母材の全域にわたって均一に構
造欠陥を消滅させることが難しいという不利がある。[Problems to be Solved by the Invention] However, if this fluorine doping is performed during gas phase hydrolysis of a silicon compound, structural defects will occur at the same time as the fluorine doping reaction in the process of producing silica particles.
Structural defects cannot be effectively eliminated by fluorine doping during the production of this porous glass base material. In addition, when a fluorine compound is added during the sintering process of the porous glass base material, transparent vitrification occurs at high temperatures, so the fluorine doping reaction occurs very quickly due to the diffusion of fluorine, but the shrinkage of the porous glass base material fluorine doping occurs at the same time, so when a small amount of fluorine compound is added, this fluorine dope tends to be large at the periphery of the base material and less at the center, and at the same time a convex refractive index distribution is formed. It has the disadvantage that structural defects remain in the center, and when fluorine is doped during the dehydration process during sintering, the fluorine doping reaction is faster than the fluorine diffusion, so the vitrification temperature of the fluorine-doped quartz base material decreases. Since the porous glass base material shrinks during the process, there is a disadvantage that it is difficult to eliminate structural defects uniformly over the entire area of the base material with a small amount of fluorine.
なお、この構造欠陥を消滅させる効果的なドープ剤とし
ては通常脱水に用いられる塩素化合物も考えられるけれ
ども、けい素と塩素の結合がけい素とフッ素の結合より
弱く、光ファイバ用母材の延伸やファイバ紡糸などの高
温での処理条件によってはけい素と塩素の結合が切れて
構造欠陥が再生され易いことから、この塩素化合物によ
って構造欠陥を効果的に消滅させることは困難である。Although chlorine compounds, which are commonly used for dehydration, can be considered as an effective doping agent to eliminate these structural defects, the bond between silicon and chlorine is weaker than the bond between silicon and fluorine, making it difficult to stretch the optical fiber base material. It is difficult to effectively eliminate structural defects with this chlorine compound because the bonds between silicon and chlorine are likely to be broken and structural defects are likely to be regenerated depending on high-temperature treatment conditions such as fiber spinning or fiber spinning.
［課題を解決するための手段〕
本発明はこのような不利、欠点を解決した光ファイバ用
母材およびその°製造方法に関するもので、これはガス
状のけい素化合物を酸水素火炎で加水分解して得たガラ
ス微粒子を担体上に堆積して、多孔質ガラス母材とし、
これを焼結、ガラス化してなる光ファイバ用母材におい
て、コア部および／またはクラッド部がフッ素を実質的
に０．０１〜０．２重量％含有するものであることを特
徴とする光ファイバ用母材、およびガス状のけい素化合
物を酸水素火炎で加水分解してガラス微粒子を生成させ
、担体上に堆積して多孔質ガラス母材を作り、ついでこ
れをフッ素雰囲気中において２００〜１．０００℃の温
度で熱処理したのち、焼結ガラス化することを特徴とす
る光ファイバ用母材の製造方法に関するものである。[Means for Solving the Problems] The present invention relates to an optical fiber base material that solves the above-mentioned disadvantages and drawbacks, and a method for producing the same. The obtained glass particles are deposited on a carrier to form a porous glass base material,
An optical fiber base material obtained by sintering and vitrifying the same, wherein the core portion and/or cladding portion substantially contains 0.01 to 0.2% by weight of fluorine. A porous glass base material is produced by hydrolyzing a glass base material and a gaseous silicon compound with an oxyhydrogen flame, and deposited on a carrier to create a porous glass base material, which is then heated in a fluorine atmosphere to The present invention relates to a method for producing an optical fiber base material, which is characterized in that it is heat-treated at a temperature of .000° C. and then sintered and vitrified.
すなわち、本発明者らは構造欠陥の少ない光ファイバ用
母材を得る方法について種々検討した結果、光ファイバ
用母材に存在する構造欠陥は主に多孔質ガラス母材の製
造工程およびその焼結工程で発生するが、この構造欠陥
の生成を防止するにはけい素との結合が強く、熱的にも
化学的にも安定であるフッ素ドープによってこの構造欠
陥を埋めることが有効であり、このフッ素を光ファイバ
用母材のコア部および／またはクラッド部にこれが０．
０１〜０．２重量％となる量で添加することが効果的で
あることを見出すと共に、このフッ素ドープ方法につい
ての研究を進めて本発明を完成させた。That is, as a result of various studies conducted by the present inventors on methods for obtaining optical fiber preforms with few structural defects, it was found that the structural defects present in optical fiber preforms are mainly due to the manufacturing process of the porous glass preform and its sintering. This occurs during the process, but in order to prevent the formation of these structural defects, it is effective to fill them with fluorine dope, which has a strong bond with silicon and is thermally and chemically stable. Fluorine is added to the core and/or cladding of the optical fiber base material at a rate of 0.
They found that it is effective to add fluorine in an amount of 0.01 to 0.2% by weight, and completed the present invention by conducting research on this method of doping fluorine.
以下にこれをさらに詳述する。This will be explained in further detail below.
［作 用］
本発明はガス状のけい素化合物を酸水素火炎で加水分解
して得たガラス微粒子を担体上に堆積して多孔質ガラス
母材とし、これを焼結ガラス化して得た光ファイバ用母
材に関するものであるが、このものは火炎加水分解で得
た多孔質ガラス母材にフッ素をドープすることによって
構造欠陥の極めて少ない光ファイバ用母材とされる。[Function] The present invention produces a porous glass base material by depositing glass particles obtained by hydrolyzing a gaseous silicon compound with an oxyhydrogen flame on a carrier, and then sintering and vitrifying the glass particles. Regarding fiber preforms, this material is a porous glass preform obtained by flame hydrolysis and doped with fluorine to produce an optical fiber preform with extremely few structural defects.
この火炎加水分解で作られた多孔質ガラス母材はすでに
構造欠陥を有しており、この構造欠陥ニツイてはＥ′セ
ンタ（＝Ｓｉ・）、ＮＢＯＨＣ（ミ５ｔ−０・）、パー
オキシラジカル（ミ５ｔ−０−０・）の３形態のあるこ
とが知られているが、このような構造欠陥をもったシロ
キサン結合は他の安定なガラスのシロキサン結合よりも
反応性に富むものとなるので、これをフッ素ドープする
とこの構造欠陥は次式
％式％
の反応によって、フッ素によって容易に切断されて安定
な５ｔ−Ｆ結合を形成するので、この構造欠陥は消滅す
ることになる。The porous glass base material made by this flame hydrolysis already has structural defects, and these structural defects are caused by E′ center (=Si・), NBOHC (Mi5t-0・), and peroxy radical. It is known that there are three forms of glass (Mi5t-0-0・), and siloxane bonds with such structural defects are more reactive than siloxane bonds in other stable glasses. Therefore, when this is doped with fluorine, this structural defect is easily cleaved by fluorine to form a stable 5t-F bond through the reaction of the following formula %, and thus this structural defect disappears.
このフッ素ドープに使用するフッ素化合物としてはフッ
化炭素、フッ化塩化炭素、フッ化イオウ、フッ化けい素
、オキシフッ化けい素、具体的にはＣＦ４． Ｃ２Ｆ６
． Ｃ３ＦＢ、 ＣＣＮ２Ｆ２． ＣＣｌＦ２゜ＳＦ４
． ＳＦ６． ＳＯＦ２． ＳＯ２Ｆ２． ＳｉＦ４．
５ｉ２ＦＢ、 ５ｉ２０Ｆ６゜５ｉ３０．Ｆａなどが例
示されるが、炭素、イオウを含む化合物は炭素、イオウ
の残存によって新たな構造欠陥を生成するおそれがある
ので、これは好ましくはフッ化けい素、オキシフッ化け
い素とすることがよい。このフッ素化合物はヘリウムガ
スと混合してフッ素化合物が容積比で０．１〜１％の範
囲となるようにして併給すればよいが、多孔質ガラス母
材へのフッ素ドープは吸着水分があるとこの水分がフッ
素化合物と激しく反応してフッ化水素を生じ、多孔質ガ
ラスを損傷するので、吸着水分の存在下で行なうのは好
ましくない。また、この多孔質ガラス母材のフッ素ドー
プは多孔質ガラス母材のかさ密度がフッ素の拡散速度お
よびシリカ微粒子の反応性に影響を与えるので、低濃度
のフッ素ドープをする場合の多孔質ガラス母材のかさ密
度は０．３ｇ／ｃｍ３以下とすることが好ましい。The fluorine compounds used in this fluorine dope include carbon fluoride, carbon fluoride chloride, sulfur fluoride, silicon fluoride, silicon oxyfluoride, and specifically CF4. C2F6
．． C3FB, CCN2F2. CClF2゜SF4
．． SF6. SOF2. SO2F2. SiF4.
5i2FB, 5i20F6゜5i30. Examples include Fa, but compounds containing carbon and sulfur may generate new structural defects due to residual carbon and sulfur, so silicon fluoride and silicon oxyfluoride are preferably used. good. This fluorine compound can be mixed with helium gas and co-supplied so that the fluorine compound is in the range of 0.1 to 1% by volume. It is not preferable to carry out the process in the presence of adsorbed moisture, since this moisture reacts violently with the fluorine compound to produce hydrogen fluoride, which damages the porous glass. In addition, when doping this porous glass base material with fluorine, the bulk density of the porous glass base material affects the diffusion rate of fluorine and the reactivity of the silica particles. The bulk density of the material is preferably 0.3 g/cm3 or less.
このフッ素化合物で多孔質ガラス母材にフッ素ドープす
るために必要とされるフッ素量は０．０１重量％より小
さいと均一にドープすることが困難となるが構造欠陥を
埋めるには０．２重量％で十分であり、０．２重量％よ
り多くするとガラス化温度が低下し後工程の脱水が困難
となるので、これは０．０１〜０．２重量％の範囲とす
ることが必要とされるし、このフッ素ドープ温度は２０
０℃より低いとフッ素が多孔質ガラス母材に残存する水
分と激しく反応して多孔質ガラス母材を損傷させ、また
１、０００℃より高い温度とすると多孔質ガラス母材の
収縮が始まってフッ素の拡散が妨げられ、均一にドープ
することが困難となるので、２００〜ｉ、ｏｏｏ℃の範
囲とする必要があるが、このドープ時間はフッ素化合物
の反応性と多孔質ガラス母材の外径、かさ密度による拡
散時間を考慮して適宜に選択すればよい。The amount of fluorine required to dope the porous glass base material with this fluorine compound is less than 0.01% by weight, which makes it difficult to dope uniformly, but it is 0.2% by weight to fill in structural defects. % is sufficient, and if it exceeds 0.2% by weight, the vitrification temperature will drop and dehydration in the subsequent process will become difficult, so it is necessary to set it in the range of 0.01 to 0.2% by weight. Therefore, this fluorine doping temperature is 20
If the temperature is lower than 0℃, fluorine reacts violently with the moisture remaining in the porous glass base material and damages the porous glass base material, and if the temperature is higher than 1,000℃, the porous glass base material starts to shrink. Since diffusion of fluorine is hindered and it becomes difficult to dope uniformly, it is necessary to keep the doping temperature in the range of 200 to 1,000°C, but this doping time depends on the reactivity of the fluorine compound and the outsideness of the porous glass base material. It may be selected appropriately by considering the diffusion time depending on the diameter and bulk density.
このようにしてフッ素ドープされた多孔質ガラス母材は
これによって構造欠陥が極めて小さいものとされるので
、ついでこれを“焼結炉で加熱しガラス化し、脱水すれ
ば目的とする光ファイバ用母材とすることができるが、
これによれば構造欠陥が極めて少なく、したがって伝送
損失が極めて低く、熱安定性、耐水素特性のすぐれた光
ファイバを与える光ファイバ用母材を有利に得ることが
できるという有用性が与えられる。The porous glass base material doped with fluorine in this way has extremely small structural defects, so it is then heated in a sintering furnace to vitrify it and dehydrated to form the desired optical fiber base material. It can be used as a material, but
According to this method, it is possible to advantageously obtain an optical fiber preform that has extremely few structural defects, has extremely low transmission loss, and has excellent thermal stability and hydrogen resistance.
［実施例コ つぎに本発明の実施例をあげる。[Example code] Next, examples of the present invention will be given.
実施例１
四塩化けい素をガス化させて酸水素火炎バーナに送り、
ここでの火炎加水分解で発生したガラス微粒子を出発材
の石英ガラス棒に堆積させて直径８０ｍ＋ｎ、長さ４５
０ｍｍでかさ密度が０．２３０ｇ／ｃｍ３の多孔質ガラ
ス母材を作った。Example 1 Silicon tetrachloride is gasified and sent to an oxyhydrogen flame burner,
The glass particles generated by the flame hydrolysis here are deposited on a quartz glass rod as a starting material, with a diameter of 80 m + n and a length of 45 mm.
A porous glass base material having a thickness of 0 mm and a bulk density of 0.230 g/cm3 was prepared.
ついでこの多孔質ガラス母材を管状電気炉内にセットし
、ヘリウムガス雰囲気下で５００℃まで昇温させ、ヘリ
ウムガス３．０ＩｌＺ分に対しフッ化けい素（ＳｉＦ４
）を０．００６ ＩＬ１分の割合で混合したガス雰囲気
下に４５０℃から５００℃の温度域で滞留時間が３０分
となるように多孔質ガラス母材を８勤してこれをフッ素
処理したのち、１，１５０℃で塩素ガスを含むヘリウム
ガス雰囲気下で脱水し、ヘリウムガス雰囲気に１，４５
０℃に加熱し透明ガラス化して石英ガラスロッドを作っ
た。Next, this porous glass base material was set in a tubular electric furnace, heated to 500°C in a helium gas atmosphere, and silicon fluoride (SiF4
) in a gas atmosphere mixed at a ratio of 0.006 IL/min for 8 times in a temperature range of 450°C to 500°C for a residence time of 30 minutes, and then treated with fluorine. , dehydrated at 1,150°C in a helium gas atmosphere containing chlorine gas, and 1,45% in a helium gas atmosphere.
It was heated to 0°C to make it transparent and a quartz glass rod was made.
つぎにこの石英ガラスロンドのフッ素含有量をしらべた
ところ、これは０．１１重量％であり、これを延伸して
純粋石英のジャケット管で被覆したものの屈折率をしら
べたところ、石英基準での屈折率低下は０．０３％であ
った。また、この石英ガラスロッドをコアとしてその外
周部に多孔質体を堆積したのち、焼結時にフッ素をドー
プして石英基準で屈折率を０．３５％下げたクラッドを
形成し、このようなりラッド部形成を２回繰返してシン
グルモード光ファイバ用母材を形成したところ、この光
ファイバ用母材の屈折率分布は第１図に示したように屈
折率差Δｎが０．３２％でクラッド／コアの径比は１３
．４であった。Next, we investigated the fluorine content of this quartz glass iron, and found that it was 0.11% by weight.When we stretched it and covered it with a pure quartz jacket tube, we examined the refractive index, and found that it was 0.11% by weight. The refractive index decrease was 0.03%. In addition, after using this quartz glass rod as a core and depositing a porous material on its outer periphery, we doped it with fluorine during sintering to form a cladding with a refractive index lowered by 0.35% based on quartz. When a single-mode optical fiber preform was formed by repeating the section formation twice, the refractive index distribution of this optical fiber preform was as shown in FIG. 1, with a refractive index difference Δn of 0.32% and a clad/ The core diameter ratio is 13
．． It was 4.
なお、この光ファイバ用母材についてはこれを紡糸して
外径＋２５ＩＪｍ 、長さ６ＫＩＴｌのファイバとし、
このファイバ特性を測定したところ、波長！、３．ｕ＋
ｎ、１．５５μｍでの伝送損失はそれぞれ０．３５ｄＢ
／Ｋｍ。This optical fiber base material was spun into a fiber with an outer diameter of +25 IJm and a length of 6 KITl.
When we measured the characteristics of this fiber, we found that the wavelength! , 3. u+
The transmission loss at n and 1.55 μm is 0.35 dB, respectively.
/Km.
０．１８ｄＢ／に１で１．３９４ｍの水酸基による吸収
も０．７ｄＢ／ＫｒＱと良好であり、これには０．６４
ｏｎから１．［ｉ４ｍの波長範囲での構造欠陥による特
異な吸収ピークは認められなかった。また、この光ファ
イバについては１気圧の水素ガス雰囲気下に２００℃で
４時間熱処理を行なったところ、水素の拡散によるｌ、
２４μｍの水素ガス吸収がわずか０．０３ｄＢ／にｍ増
加した以外は構造欠陥による新たな吸収ピークは見られ
ず、１．３μｍ、 １．５５μｍの両波長における損失
値に変化はなかった。The absorption by the hydroxyl group of 1.394 m at 0.18 dB/1 is also good at 0.7 dB/KrQ, which includes 0.64
1 from on. [No unique absorption peak due to structural defects was observed in the i4m wavelength range. When this optical fiber was heat-treated at 200°C for 4 hours in a hydrogen gas atmosphere of 1 atm, it was found that due to the diffusion of hydrogen, l,
No new absorption peaks due to structural defects were observed, except that the hydrogen gas absorption at 24 μm increased by only 0.03 dB/m, and there was no change in the loss value at both wavelengths of 1.3 μm and 1.55 μm.
実施例２
四塩化けい素をガス化させて酸水素火炎バーナーに送り
、ここでの火炎加水分解で発生したシリカ微粒子を出発
材の石英ガラス棒に堆積させ、この際コア部はゲルマニ
ウムをドープし、クラッド部は純石英として直径１００
ｍｍ 、長さ［ｉ００＋ｎｍでかさ密度が０．２１ｇ／
ｃｍ３であるコア部とクラッド部より成る多孔質ガラス
母材を一体合成で製造した。Example 2 Silicon tetrachloride is gasified and sent to an oxyhydrogen flame burner, and the silica fine particles generated by flame hydrolysis here are deposited on a quartz glass rod as a starting material. At this time, the core portion is doped with germanium. , the cladding part is made of pure quartz with a diameter of 100 mm.
mm, length [i00+nm and bulk density 0.21 g/
A porous glass base material consisting of a core portion and a cladding portion having a size of cm3 was manufactured by integral synthesis.
ついでこの多孔質ガラス母材を管状電気炉にセットし、
ヘリウムガス雰囲気下で６００℃まで昇温させ、ヘリウ
ムガス６．０℃／分に対してフッ化けい素（ＳｉＦ＋）
を０．０ＯＩｉ １１／分の割合で混合したガス７囲気
下に５５０℃から６００℃の温度域での滞留時間が３５
分となるように多孔質ガラス母材を移動してフッ素処理
したのち、１，２００℃で塩素ガスを含むヘリウムガス
雰囲気下で脱水し、ヘリウムガス雰囲気に１，４３０℃
に加熱し透明ガラス化して石英ガラスロッドを作った。Next, set this porous glass base material in a tubular electric furnace,
Silicon fluoride (SiF+) was heated to 600℃ in a helium gas atmosphere, and silicon fluoride (SiF+)
The residence time in the temperature range from 550℃ to 600℃ under 7 atmospheres is 35 minutes.
After moving the porous glass base material to a temperature of 300°C and subjecting it to fluorine treatment, it was dehydrated at 1,200°C in a helium gas atmosphere containing chlorine gas, and then heated to 1,430°C in a helium gas atmosphere.
A quartz glass rod was made by heating it to a transparent vitrification.
つぎにこの石英ガラスロッドを延伸し純粋石英のジャケ
ットで被覆したものの屈折率をしらべたところ、コア部
の屈折率上昇が０．３１％、クラッド部の屈折率低下が
０．０２％で、このクラッド／コアの径比は４．８であ
り、このコア部、クラッド部のフッ素含有量は化学分析
の結果、いずれも０．０７５重量％であった。また、こ
の石英ガラスロッドの外周部にシリカ微粒子よりなる多
孔質体を堆積したのち、フッ素のドープ方法は本例と同
じ方法で行ない、透明ガラス化してシングルモード光フ
ァイバ用母材を形成したところ、この光ファイバ用母材
の屈折率分布は第２図に示したようにコア部の屈折率上
昇が０．３１％、クラッド部の屈折率低下が０．０２％
、コア部とクラッド部との相対的屈折率差は０．３３％
であり、このもののクラッド部／コア部の径比は１４．
５であった。Next, when we examined the refractive index of this quartz glass rod stretched and covered with a pure quartz jacket, we found that the refractive index increase in the core part was 0.31%, and the refractive index decrease in the cladding part was 0.02%. The clad/core diameter ratio was 4.8, and the fluorine content in both the core and clad parts was 0.075% by weight as a result of chemical analysis. In addition, after depositing a porous material made of fine silica particles on the outer periphery of this quartz glass rod, the fluorine doping method was carried out in the same manner as in this example, and the material was made into transparent glass to form a base material for a single mode optical fiber. As shown in Figure 2, the refractive index distribution of this optical fiber base material is such that the refractive index increase in the core part is 0.31% and the refractive index decrease in the cladding part is 0.02%.
, the relative refractive index difference between the core part and the cladding part is 0.33%
The cladding/core diameter ratio of this product is 14.
It was 5.
なお、この光ファイバ用母材を外径１２５ＩＪｍ 、長
さ８にｍのファイバに紡糸し、このファイバ特性を測定
したところ、波長１．３４１１１１．１．５５μｍでの
伝送損失がそれぞれ０．３７ｄＢ／にｍ、 ０．１９ｄ
Ｂ／Ｋｍであり、１．３９μｍの水酸基による吸収もｏ
、２ｄａ／にｍと良好であり、これには０ 、６ｐｍか
ら１．６１Ｊｍの波長範囲での構造欠陥による特異な吸
収ピークは認められなかった。When this optical fiber base material was spun into a fiber with an outer diameter of 125 IJm and a length of 8 m, the fiber characteristics were measured, and the transmission loss at a wavelength of 1.3411111.1.55 μm was 0.37 dB/m, respectively. m, 0.19d
B/Km, and the absorption by hydroxyl group of 1.39μm is also o
, 2 da/m, and no peculiar absorption peak due to structural defects was observed in the wavelength range from 0.6 pm to 1.61 Jm.
また、この光ファイバについてはこれを１気圧の水素ガ
ス雰囲気下に２００℃で４時間熱処理したが、水素ガス
の拡散による１、２４μｍの水素ガスによる吸収が僅か
０．０４ｄＢ／にｍ増加した以外は構造欠陥による新た
な吸収ピークは見られず、１ 、３ｐｍ 。Furthermore, this optical fiber was heat-treated at 200°C for 4 hours in a hydrogen gas atmosphere of 1 atm, but the absorption by hydrogen gas of 1.24 μm due to diffusion of hydrogen gas increased by only 0.04 dB/m. No new absorption peaks due to structural defects were observed at 1.3 pm.
１．５５ｔＪｍの両波長における損失値に変化はなかっ
た。比較例
実施例１と同じ方法で多孔質ガラス母材を作ったが、こ
の多孔質ガラス母材については焼結時にフッ素処理をせ
ずに実施例１と同じ方法で脱水、焼結して石英ガラスロ
ッドを作り、この石英ガラスロッドを延伸してコア部と
し、その外周部に多孔質体を堆積し、これを焼結すると
きにフッ素ドープをして純粋石英基準で屈折率低下が０
．３２％となるクラッド部を形成し、このように多孔質
体の堆積と焼結時のフッ素ドープを２回繰り返してシン
グルモード光ファイバ用母材を作ったところ、この光フ
ァイバ用母材の屈折率分布は第３図に示したように屈折
率差が０．３２％であり、このもののクラッド部／コア
部の径比は１３，４であった。There was no change in the loss value at both wavelengths of 1.55 tJm. Comparative Example A porous glass base material was made in the same manner as in Example 1, but this porous glass base material was dehydrated and sintered in the same manner as in Example 1 without fluorine treatment during sintering to form quartz. A glass rod is made, this quartz glass rod is stretched to form a core part, a porous material is deposited on the outer periphery of the rod, and when this is sintered, it is doped with fluorine so that the refractive index decrease is 0 compared to pure quartz.
．． When a single-mode optical fiber base material was made by forming a cladding portion with a 32% concentration and repeating the deposition of the porous material and the fluorine doping during sintering twice, the refraction of this optical fiber base material was As shown in FIG. 3, the refractive index difference was 0.32%, and the cladding/core diameter ratio was 13.4.
ついで、この光ファイバ用母材を外径１２５μｍ、長さ
６にｍのファイバに紡糸してそのファイバ特性を測定し
たところ、波長１．３μｍ、１．５５μｍでの伝送損失
がそれぞれ０．５５ｄＢ／にｍ、 ０．３２ ｄＢ／Ｋ
ｍで、１．３９７、ｉｍでの水酸基による吸収も１１．
２ｄＢ／Ｋｍであり、これはまた０、６３μｍに構造欠
陥にもとづく吸収ピークがみられ、０．６３．ｕｍでの
伝送損失もｌｏ、８ｄＢ／Ｋｍであった。Next, this optical fiber base material was spun into a fiber with an outer diameter of 125 μm and a length of 6 m, and the fiber characteristics were measured. As a result, the transmission loss at wavelengths of 1.3 μm and 1.55 μm was 0.55 dB/m, respectively. m, 0.32 dB/K
m is 1.397, absorption by hydroxyl group at im is also 11.
2 dB/Km, which also shows an absorption peak at 0.63 μm due to structural defects, and 0.63 μm. The transmission loss at um was also lo, 8 dB/Km.
また、この光ファイバについてはこれを１気圧の水素ガ
ス雰囲気下に２００℃で４時間熱処理したところ、波長
１．２４μｍ、 １．３９％ｍでそれぞれ２．５ｄＢ／
にｍ、 ４．０ｄＢ／Ｋｍの損失増加がみられたほか、
１．５２．ａｍに構造欠陥による＠、収ビークＱ、１（
ｌｄＢ／にｍが生じ、１．３ｐｍ、 １．５５４ＩＩ１
１における伝送損失もそれぞれ０．６２ｄＢ／Ｋｍ、
０．４０ｄＢ／にｍに増加した。In addition, when this optical fiber was heat-treated at 200°C for 4 hours in a hydrogen gas atmosphere of 1 atm, the optical fiber was heated to 2.5 dB/2 at wavelengths of 1.24 μm and 1.39% m, respectively.
In addition to the increase in loss of 4.0 dB/Km,
1.52. @ due to structural defects in am, collection peak Q, 1 (
m occurs in ldB/, 1.3pm, 1.554II1
The transmission loss at 1 is also 0.62 dB/Km, respectively.
increased to 0.40 dB/m.
第１図は本発明の実施例１において製造された光ファイ
バ用母材の屈折率分布図、第２図は本発明の実施例２に
おいて製造された光ファイバ用母材の屈折率分布図、第
３図は比較例において製造された光ファイバ用母材の屈
折率分布図を示したものである。
第１図
第２図
Ｄ７”１３．４FIG. 1 is a refractive index distribution diagram of the optical fiber base material manufactured in Example 1 of the present invention, FIG. 2 is a refractive index distribution diagram of the optical fiber base material manufactured in Example 2 of the present invention, FIG. 3 shows a refractive index distribution diagram of an optical fiber base material manufactured in a comparative example. Figure 1 Figure 2 D7”13.4
Claims (1)
得たガラス微粒子を担体上に堆積して、多孔質ガラス母
材とし、これを焼結、ガラス化してなる光ファイバ用母
材において、コア部および／またはクラッド部がフッ素
を実質的に０．０１〜０．２重量％含有するものである
ことを特徴とする光ファイバ用母材。 ２、ガス状のけい素化合物を酸水素火炎で加水分解して
ガラス微粒子を生成させ、担体上に堆積して多孔質ガラ
ス母材を作り、ついでこれをフッ素雰囲気中において２
００〜１，０００℃の温度で熱処理したのち、焼結、ガ
ラス化することを特徴とする請求項１に記載の光ファイ
バ用母材の製造方法。 ３、フッ素雰囲気がフッ素化合物とヘリウムとからなる
ものである請求項２に記載の光ファイバ用母材の製造方
法。 ４、多孔質ガラス母材のカサ密度が０．３ｇ／ｃｍ＾３
以下である請求項２に記載の光ファイバ用母材の製造方
法。[Claims] 1. Fine glass particles obtained by hydrolyzing a gaseous silicon compound with an oxyhydrogen flame are deposited on a carrier to form a porous glass base material, which is then sintered and vitrified. 1. A preform for an optical fiber, characterized in that the core portion and/or the cladding portion substantially contain 0.01 to 0.2% by weight of fluorine. 2. Gaseous silicon compounds are hydrolyzed with an oxyhydrogen flame to produce glass particles, which are deposited on a carrier to create a porous glass matrix, which is then placed in a fluorine atmosphere to produce glass particles.
2. The method for manufacturing an optical fiber preform according to claim 1, wherein the preform is heat-treated at a temperature of 00 to 1,000[deg.] C., and then sintered and vitrified. 3. The method for manufacturing an optical fiber preform according to claim 2, wherein the fluorine atmosphere consists of a fluorine compound and helium. 4. The bulk density of the porous glass base material is 0.3 g/cm^3
The method for manufacturing an optical fiber preform according to claim 2, which is as follows.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1143269A JPH0813689B2 (en) | 1989-06-06 | 1989-06-06 | Manufacturing method of optical fiber preform |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1143269A JPH0813689B2 (en) | 1989-06-06 | 1989-06-06 | Manufacturing method of optical fiber preform |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH038743A true JPH038743A (en) | 1991-01-16 |
| JPH0813689B2 JPH0813689B2 (en) | 1996-02-14 |
Family
ID=15334824
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1143269A Expired - Lifetime JPH0813689B2 (en) | 1989-06-06 | 1989-06-06 | Manufacturing method of optical fiber preform |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0813689B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2000024685A1 (en) * | 1998-10-28 | 2000-05-04 | Asahi Glass Company Ltd. | Synthetic quartz glass and method for production thereof |
| WO2000039040A1 (en) * | 1998-12-25 | 2000-07-06 | Asahi Glass Company, Limited | Synthetic quartz glass and method for preparation thereof |
| JP2012246157A (en) * | 2011-05-26 | 2012-12-13 | Ohara Inc | Method for producing synthetic silica glass and the synthetic silica glass |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6096545A (en) * | 1983-10-28 | 1985-05-30 | Nippon Telegr & Teleph Corp <Ntt> | Optical fiber |
-
1989
- 1989-06-06 JP JP1143269A patent/JPH0813689B2/en not_active Expired - Lifetime
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6096545A (en) * | 1983-10-28 | 1985-05-30 | Nippon Telegr & Teleph Corp <Ntt> | Optical fiber |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2000024685A1 (en) * | 1998-10-28 | 2000-05-04 | Asahi Glass Company Ltd. | Synthetic quartz glass and method for production thereof |
| US6499317B1 (en) | 1998-10-28 | 2002-12-31 | Asahi Glass Company, Limited | Synthetic quartz glass and method for production thereof |
| US7022633B2 (en) | 1998-10-28 | 2006-04-04 | Asahi Glass Company, Limited | Synthetic quartz glass and process for producing it |
| WO2000039040A1 (en) * | 1998-12-25 | 2000-07-06 | Asahi Glass Company, Limited | Synthetic quartz glass and method for preparation thereof |
| EP1067097A4 (en) * | 1998-12-25 | 2004-03-31 | Asahi Glass Co Ltd | Synthetic quartz glass and method for preparation thereof |
| JP2012246157A (en) * | 2011-05-26 | 2012-12-13 | Ohara Inc | Method for producing synthetic silica glass and the synthetic silica glass |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0813689B2 (en) | 1996-02-14 |
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