JPS6327296B2 - - Google Patents
Info
- Publication number
- JPS6327296B2 JPS6327296B2 JP56071949A JP7194981A JPS6327296B2 JP S6327296 B2 JPS6327296 B2 JP S6327296B2 JP 56071949 A JP56071949 A JP 56071949A JP 7194981 A JP7194981 A JP 7194981A JP S6327296 B2 JPS6327296 B2 JP S6327296B2
- Authority
- JP
- Japan
- Prior art keywords
- sintered body
- glass
- glass sintered
- refractive index
- optical fiber
- 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
- 239000011521 glass Substances 0.000 claims description 36
- 238000009826 distribution Methods 0.000 claims description 28
- 239000013307 optical fiber Substances 0.000 claims description 17
- 239000000463 material Substances 0.000 claims description 13
- 238000000034 method Methods 0.000 claims description 13
- 239000002019 doping agent Substances 0.000 claims description 12
- 239000002994 raw material Substances 0.000 claims description 11
- 238000004519 manufacturing process Methods 0.000 claims description 6
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 5
- 230000012010 growth Effects 0.000 claims description 5
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 claims description 4
- 229910001882 dioxygen Inorganic materials 0.000 claims description 4
- 239000007789 gas Substances 0.000 claims description 2
- 239000002245 particle Substances 0.000 claims description 2
- 238000004017 vitrification Methods 0.000 claims description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims 1
- 239000001257 hydrogen Substances 0.000 claims 1
- 229910052739 hydrogen Inorganic materials 0.000 claims 1
- 239000001301 oxygen Substances 0.000 claims 1
- 229910052760 oxygen Inorganic materials 0.000 claims 1
- 230000005540 biological transmission Effects 0.000 description 6
- 239000010419 fine particle Substances 0.000 description 4
- 238000006460 hydrolysis reaction Methods 0.000 description 3
- 238000007254 oxidation reaction Methods 0.000 description 3
- 230000002194 synthesizing effect Effects 0.000 description 3
- 229910005793 GeO 2 Inorganic materials 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- YBMRDBCBODYGJE-UHFFFAOYSA-N germanium dioxide Chemical compound O=[Ge]=O YBMRDBCBODYGJE-UHFFFAOYSA-N 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 230000021332 multicellular organism growth Effects 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- 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 1
- 229910004298 SiO 2 Inorganic materials 0.000 description 1
- UIZLQMLDSWKZGC-UHFFFAOYSA-N cadmium helium Chemical compound [He].[Cd] UIZLQMLDSWKZGC-UHFFFAOYSA-N 0.000 description 1
- 229940119177 germanium dioxide Drugs 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000000386 microscopy Methods 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 239000010453 quartz Substances 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 239000005049 silicon tetrachloride Substances 0.000 description 1
- IEXRMSFAVATTJX-UHFFFAOYSA-N tetrachlorogermane Chemical compound Cl[Ge](Cl)(Cl)Cl IEXRMSFAVATTJX-UHFFFAOYSA-N 0.000 description 1
- 239000012808 vapor phase Substances 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]
- C03B37/01413—Reactant delivery systems
- C03B37/0142—Reactant deposition burners
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B2207/00—Glass deposition burners
- C03B2207/60—Relationship between burner and deposit, e.g. position
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B2207/00—Glass deposition burners
- C03B2207/70—Control measures
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)
- Manufacture, Treatment Of Glass Fibers (AREA)
Description
【発明の詳細な説明】
本発明は気相連続軸付法（VAD法）により、
光フアイバ用母材を製造するようにした方法に関
する。[Detailed description of the invention] The present invention uses the vapor phase continuous axial attachment method (VAD method) to
The present invention relates to a method for producing a base material for optical fiber.
光通信用伝送媒体として用いられる光フアイバ
は、一般に光フアイバの母材をあらかじめ合成
し、この母材を加熱溶融して線引きして得られ
る。この際に使用する母材は、既知のVAD法や
MCVD法、OVPO法等によつて製造されている。 Optical fibers used as transmission media for optical communications are generally obtained by synthesizing an optical fiber base material in advance, heating and melting this base material, and drawing the base material. The base material used in this case is the known VAD method or
Manufactured by MCVD method, OVPO method, etc.
この光フアイバを用いて伝送できる情報量は伝
送帯域に依存しており、この伝送帯域は光フアイ
バコア部の屈折率分布によつて制限されている。 The amount of information that can be transmitted using this optical fiber depends on the transmission band, and this transmission band is limited by the refractive index distribution of the optical fiber core.
このため、光フアイバ中心部の屈折率が高く、
周辺部の屈折率が低くなるように、また２乗分布
に近い屈折率分布となるように、光フアイバコア
部を制御する必要がある。 Therefore, the refractive index at the center of the optical fiber is high,
It is necessary to control the optical fiber core portion so that the refractive index of the peripheral portion is low and the refractive index distribution is close to a square distribution.
MCVD法やOVPO法は、ガラス原料中のドー
パント（一般にGeCl4やPCl3は屈折率を高め、
BBr3やBCl3は屈折率を低下させる）量を半径方
向について変化させ、成分の異なつたガラス層を
多数半径方向に合成することによつて屈折率分布
を制御している。 In the MCVD method and OVPO method, dopants in the glass raw materials (generally GeCl 4 and PCl 3 increase the refractive index,
The refractive index distribution is controlled by varying the amount of BB r3 and BCl 3 (which lower the refractive index) in the radial direction and by synthesizing many glass layers with different components in the radial direction.
VAD法では、MCVD法やOVPO法とは異な
り、ドーパントを含んだガラス原料を高温に加熱
し、酸化反応および加水分解反応によつて、ガラ
ス微粒子を生成し、かつ各々のガス流量、バーナ
の設置条件等を変えることにより、半径方向の屈
折率分布を瞬間的に形成しながら、軸方向に連続
的に光フアイバ母材を合成している。 Unlike the MCVD method and OVPO method, in the VAD method, glass raw materials containing dopants are heated to high temperatures, and glass fine particles are generated through oxidation and hydrolysis reactions. By changing the conditions, etc., the optical fiber base material is synthesized continuously in the axial direction while instantaneously forming the refractive index distribution in the radial direction.
このため、高速でガラス焼結体を生成すること
ができるという大きな特徴を有しているが、酸化
反応および加水分解反応を利用しているので、バ
ーナのガス流量条件の変動、バーナ設置条件の設
定変動によつて、得られる屈折率分布も所望の分
布と異なつてしまう。その結果、伝送帯域が狭く
なるという問題があつた。 For this reason, it has the great feature of being able to produce glass sintered bodies at high speed, but since it uses oxidation reactions and hydrolysis reactions, it is possible to change the burner gas flow conditions and the burner installation conditions. Due to setting variations, the obtained refractive index distribution also differs from the desired distribution. As a result, there was a problem that the transmission band became narrow.
本発明はこれらの問題を解決するためになされ
たもので、ガラス焼結体の成長面に紫外線を照射
し、ガラス焼結体中に含まれている元素（主にド
ーパント）の螢光を検出することによつて屈折率
分布を検出し、該分布を所望の分布と一致するよ
うに、製造条件を制御することを特徴としたもの
であり、その目的は所望の屈折率分布を有する光
フアイバ母材を製造することにある。 The present invention was made to solve these problems, and the growth surface of the glass sintered body is irradiated with ultraviolet rays, and the fluorescence of the elements (mainly dopants) contained in the glass sintered body is detected. It is characterized by detecting the refractive index distribution by detecting the refractive index distribution and controlling the manufacturing conditions so that the distribution matches the desired distribution.The purpose is to manufacture an optical fiber having the desired refractive index distribution. The purpose is to manufacture the base material.
第１図は本発明の一実施例の構成図であつて、
１はバーナ、２はガラス焼結体、３は紫外線の光
源、４は偏向器、５はガラス焼結体成長面、６は
カメラ、７は紫外線、１０はガラス原料、１１は
ドーパント原料、１２は酸素ガス、１３は水素ガ
ス、３０は１０，１１，１２，１３の流量制御
系、１４はガラスとドーパントの微粒子、２０は
信号処理系、２１は屈折率分布信号発生器、２２
は演算機である。 FIG. 1 is a configuration diagram of an embodiment of the present invention,
1 is a burner, 2 is a glass sintered body, 3 is an ultraviolet light source, 4 is a deflector, 5 is a glass sintered body growth surface, 6 is a camera, 7 is an ultraviolet ray, 10 is a glass raw material, 11 is a dopant raw material, 12 is oxygen gas, 13 is hydrogen gas, 30 is a flow rate control system for 10, 11, 12, and 13, 14 is glass and dopant fine particles, 20 is a signal processing system, 21 is a refractive index distribution signal generator, 22
is a computing machine.
つぎにこれを動作するには、バーナ１に水素ガ
ス１３と酸素ガス１２を導入して燃焼させる。こ
の中にガラス原料１０、ドーパント原料１１を供
給して、高温火炎中で酸化反応および加水分解反
応によつて、ガラスとドーパントの微粒子１４を
合成する。 Next, to operate this, hydrogen gas 13 and oxygen gas 12 are introduced into the burner 1 and burned. A glass raw material 10 and a dopant raw material 11 are supplied into this, and glass and dopant fine particles 14 are synthesized by an oxidation reaction and a hydrolysis reaction in a high-temperature flame.
この微粒子は回転しながら、かつ成長速度と同
期して上方に引き上げられているガラス焼結体２
の成長面５に堆積する。 The fine particles are rotated and pulled upward in synchronization with the growth rate of the glass sintered body 2.
is deposited on the growth surface 5 of.
一方、光源３から発した紫外線７を偏向器４で
ガラスの焼結体の成長面５の直径上を走査するよ
うに偏向する。 On the other hand, the ultraviolet light 7 emitted from the light source 3 is deflected by a deflector 4 so as to scan the diameter of the growth surface 5 of the glass sintered body.
紫外線に照射されたガラス焼結体中の元素は、
その元素に応じた螢光を発光するが、その螢光の
強度は、元素の含有量に応じて変化する。 The elements in the glass sintered body exposed to ultraviolet light are
It emits fluorescent light depending on the element, and the intensity of the fluorescent light changes depending on the content of the element.
この螢光をカメラ６で記録し、信号処理系２０
で半径方向の元素含有量に変換し、屈折率分布を
算出する。 This fluorescence is recorded by the camera 6, and the signal processing system 20
Convert to the element content in the radial direction and calculate the refractive index distribution.
ついで、屈折率分布信号発生器２１で発生させ
た所望の屈折率分布信号と信号処理系２０の出力
信号を演算機２２で比較し、その差分に応じた信
号を流量制御系３０へフイードバツクする。 Next, the desired refractive index distribution signal generated by the refractive index distribution signal generator 21 and the output signal of the signal processing system 20 are compared by the calculator 22, and a signal corresponding to the difference is fed back to the flow rate control system 30.
この実施例は以上説明した構成となつているの
で、ガラス焼結体を合成しながら、その半径方向
の屈折率分布を所望の値に調整することができ
る。 Since this embodiment has the configuration described above, the refractive index distribution in the radial direction can be adjusted to a desired value while synthesizing the glass sintered body.
つぎに、本発明の具体的な実施例について述べ
る。 Next, specific examples of the present invention will be described.
バーナ１中に10％の四塩化ゲルマニウムをドー
パントとして含む四塩化けい素を毎分300c.c.流し、
半径60mmφのガラス焼結体２を合成速度25ｇ／分
で合成した。この際、ガラス焼結体の成長面を照
射する光線として、ヘリウム・カドミウム（He
−Cd）レーザから発する波長0.325μｍの紫外線
を用いた。 Flowing silicon tetrachloride containing 10% germanium tetrachloride as a dopant into burner 1 at a rate of 300 c.c./min.
A glass sintered body 2 having a radius of 60 mmφ was synthesized at a synthesis rate of 25 g/min. At this time, helium cadmium (He
-Cd) Ultraviolet light with a wavelength of 0.325 μm emitted from a laser was used.
この紫外線はガラス焼結体の直径を走査するよ
うに、ガルバノメータ型偏向器を用いて調整し
た。 This ultraviolet light was adjusted using a galvanometer type deflector so as to scan the diameter of the glass sintered body.
ガラス焼結体中にドーパントとして含まれてい
る二酸化ゲルマニウム（GeO2）は、波長0.24μｍ
〜0.38μｍの所に吸収帯を有しており、この吸収
によつて波長0.42μｍ近傍において螢光を発した。
この螢光をビデオカメラで記憶し、その強度分布
を測定し、屈折率分布に換算した。 Germanium dioxide (GeO 2 ) contained as a dopant in the glass sintered body has a wavelength of 0.24 μm.
It has an absorption band at ~0.38 μm, and this absorption causes it to emit fluorescence at a wavelength of around 0.42 μm.
This fluorescence was recorded with a video camera, and its intensity distribution was measured and converted into a refractive index distribution.
0.325μｍの紫外線は、GeO2の存在によつて螢
光を発し、ガラスの主成分SiO2では観察できな
かつた。このようにして測定した屈折率分布の測
定結果と、同一ガラス焼結体から透明ガラス化に
よつて得られた光フアイバ母材を干渉顕微鏡法に
よつて求めた屈折率分布と比較した結果、屈折率
差の測定精度は±２×10-4程度であつた。 Ultraviolet rays of 0.325 μm emitted fluorescence due to the presence of GeO 2 and could not be observed with SiO 2 , the main component of the glass. As a result of comparing the measurement results of the refractive index distribution measured in this way with the refractive index distribution determined by interference microscopy of an optical fiber base material obtained by transparent vitrification from the same glass sintered body, The measurement accuracy of the refractive index difference was approximately ±2×10 −4 .
ついで、流量制御系３０を用いて所望の屈折率
分布となるように、フイードバツクしながら合成
したガラス焼結体を透明ガラス化した。 Next, the synthesized glass sintered body was made into transparent glass while feedback was provided using the flow rate control system 30 so as to obtain a desired refractive index distribution.
コア部の直径が50μｍ、外径が125μｍの光フア
イバとなるように、光フアイバ母材の表面に市販
の石英管をかぶせて寸法合わせをし、10Km〜50Km
長の光フアイバに線引きした。 A commercially available quartz tube is placed over the surface of the optical fiber base material to adjust the dimensions so that the core diameter is 50 μm and the outer diameter is 125 μm.
A line was drawn on the long optical fiber.
これらの光フアイバの伝送帯域を波長1.3μｍの
半導体レーザを光源として、ベースバンドスイー
プ法によつて測定したところ、6dB低下帯域周波
数の平均値は2GHz・Kmであり、最低でも1.5G
Hz・Kmであつた。 When the transmission band of these optical fibers was measured by the baseband sweep method using a semiconductor laser with a wavelength of 1.3 μm as a light source, the average value of the band frequency with a 6 dB decrease was 2 GHz Km, which was at least 1.5 G.
It was hot in Hz/Km.
以上説明したように、本発明の方法によると、
光フアイバ母材合成中の屈折率分布をオンライン
で測定しながら、所望の屈折率分布に制御するこ
とが可能であるので、伝送帯域の広い光フアイバ
の母材を合成できる利点がある。 As explained above, according to the method of the present invention,
Since it is possible to control the refractive index distribution to a desired one while measuring the refractive index distribution online during synthesis of the optical fiber base material, there is an advantage that it is possible to synthesize an optical fiber base material with a wide transmission band.
図は本発明の一実施例の構成図である。
１……バーナ、２……ガラス焼結体、３……紫
外線の光源、４……偏向器、５……ガラス焼結体
成長面、６……カメラ、７……紫外線、１０……
ガラス原料、１１……ドーパント原料、１２……
酸素ガス、１３……水素ガス、１４……ガラスと
ドーパントの微粒子、２０……信号処理系、２１
……屈折率分布信号発生器、２２……演算機、３
０……１０，１１，１２，１３の流量制御系。
The figure is a configuration diagram of an embodiment of the present invention. 1... Burner, 2... Glass sintered body, 3... Ultraviolet light source, 4... Deflector, 5... Glass sintered body growth surface, 6... Camera, 7... Ultraviolet light, 10...
Glass raw material, 11... Dopant raw material, 12...
Oxygen gas, 13...Hydrogen gas, 14...Glass and dopant particles, 20...Signal processing system, 21
... Refractive index distribution signal generator, 22 ... Computing machine, 3
0...10, 11, 12, 13 flow rate control system.
Claims (1)
にガラス成分を含む原料ガスを導いてガラス化反
応を起こし、ガラス焼結体を種棒下端に堆積さ
せ、順次種棒を上方に移動させてガラス焼結体を
長さ方向に成長させるようにした光フアイバ用母
材の製造方法において、 ガラス焼結体成長面に紫外線を照射し、ガラス
焼結体に含まれている元素が紫外線照射によつて
発する螢光を検出することによつて、ガラス焼結
体に含まれている元素の分布を測定し、該分布と
所望の分布が一致するように、ガラス原料、ドー
パント原料、酸素ガスおよび水素ガスの供給流量
を調整することを特徴とする光フアイバ母材の製
造方法。[Claims] 1 Oxygen hydrogen is burned in a burner, and a raw material gas containing a glass component is introduced into the oxyhydrogen flame to cause a vitrification reaction, and a glass sintered body is deposited at the lower end of the seed rod, and the seed rod is sequentially heated. In a method for manufacturing an optical fiber base material in which a rod is moved upward to grow a glass sintered body in the lengthwise direction, ultraviolet rays are irradiated onto the growth surface of the glass sintered body to remove particles contained in the glass sintered body. The distribution of the elements contained in the glass sintered body is measured by detecting the fluorescence emitted by the elements contained in the glass sintered body when exposed to ultraviolet irradiation, and the glass raw materials are adjusted so that the distribution matches the desired distribution. A method for producing an optical fiber base material, which comprises adjusting the supply flow rates of a dopant raw material, oxygen gas, and hydrogen gas.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7194981A JPS57188423A (en) | 1981-05-13 | 1981-05-13 | Manufacture of base material for optical fiber |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7194981A JPS57188423A (en) | 1981-05-13 | 1981-05-13 | Manufacture of base material for optical fiber |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS57188423A JPS57188423A (en) | 1982-11-19 |
| JPS6327296B2 true JPS6327296B2 (en) | 1988-06-02 |
Family
ID=13475239
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP7194981A Granted JPS57188423A (en) | 1981-05-13 | 1981-05-13 | Manufacture of base material for optical fiber |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS57188423A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6588236B2 (en) | 1999-07-12 | 2003-07-08 | Kitagawa Industries Co., Ltd. | Method of processing a silica glass fiber by irradiating with UV light and annealing |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5650135A (en) * | 1979-09-26 | 1981-05-07 | Nippon Telegr & Teleph Corp <Ntt> | Manufacture of optical fiber base material |
-
1981
- 1981-05-13 JP JP7194981A patent/JPS57188423A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5650135A (en) * | 1979-09-26 | 1981-05-07 | Nippon Telegr & Teleph Corp <Ntt> | Manufacture of optical fiber base material |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS57188423A (en) | 1982-11-19 |
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