JPS62216934A - Device for doping treatment of porous base material for optical fiber - Google Patents
Device for doping treatment of porous base material for optical fiberInfo
- Publication number
- JPS62216934A JPS62216934A JP5909486A JP5909486A JPS62216934A JP S62216934 A JPS62216934 A JP S62216934A JP 5909486 A JP5909486 A JP 5909486A JP 5909486 A JP5909486 A JP 5909486A JP S62216934 A JPS62216934 A JP S62216934A
- Authority
- JP
- Japan
- Prior art keywords
- pressure
- reaction vessel
- optical fiber
- vessel
- gas
- 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 abstract description 33
- 239000000463 material Substances 0.000 title abstract description 14
- 239000007789 gas Substances 0.000 claims abstract description 27
- 238000010438 heat treatment Methods 0.000 claims abstract description 17
- 239000002019 doping agent Substances 0.000 claims abstract description 10
- 239000011261 inert gas Substances 0.000 claims abstract description 8
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 claims description 5
- 239000010453 quartz Substances 0.000 claims description 5
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 5
- 230000001105 regulatory effect Effects 0.000 abstract description 6
- 230000002349 favourable effect Effects 0.000 abstract 1
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 description 6
- 229910052731 fluorine Inorganic materials 0.000 description 6
- 239000011737 fluorine Substances 0.000 description 6
- 229910052751 metal Inorganic materials 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 230000009172 bursting Effects 0.000 description 2
- 229910004074 SiF6 Inorganic materials 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-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
- C03B37/0146—Furnaces therefor, e.g. muffle tubes, furnace linings
-
- 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
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Physics & Mathematics (AREA)
- General Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Thermal 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)
Abstract
Description
【発明の詳細な説明】
〈産業上の利用分野〉
本発明は、多孔質光ファイバ母材に屈折率等を変えるた
めのドーパントを効率良く含浸させるためのドーピング
処理装置に関する。DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a doping treatment apparatus for efficiently impregnating a porous optical fiber base material with a dopant for changing the refractive index and the like.
〈従来の技術〉
ＶＡＤ法で得られた多孔質光ファイ／ｓ＋母材をドーピ
ング処理する際、ドーピングガスを加圧状態にすること
によって、反応効率を高めることができることは知られ
ている。例えば、加圧された弗素系ガス下で多孔質光フ
ァイバ母材をドーピング処理することによって、多量の
弗素を多孔質光ファイバ母材中へ効果的にドープするこ
とができる。<Prior Art> It is known that when doping a porous optical fiber/s+ base material obtained by the VAD method, the reaction efficiency can be increased by pressurizing the doping gas. For example, by doping the porous optical fiber preform under pressurized fluorine-based gas, a large amount of fluorine can be effectively doped into the porous optical fiber preform.
かかる多孔質光ファイバ母材のドーピング装置の一例を
表す第２図に示すように、回転自在の支持棒１に取付け
られた多孔質光ファイバ母材２は反応圧力容器３′の中
に保持さ１＋。As shown in FIG. 2, which shows an example of such a doping apparatus for a porous optical fiber preform, a porous optical fiber preform 2 attached to a rotatable support rod 1 is held in a reaction pressure vessel 3'. 1+.
る０反応圧力容器３′は加熱体４によってドーピング処
理温度に加熱される。反応圧力容器３′中へはドーピン
グガス、例えば弗素系ではＳＦｂ 、 ＣＦ４ 、 Ｃ
２Ｆ４． ＳｉＦ＜、 Ｂ７ 、５ｉｚＦ６等が４気圧
程度の圧力に加圧供給される。反応圧力容器３′の下端
のガス供給ロアからこのようなドーピングガスが供給さ
れ、上端のガス排出口８から排出される。なお、図中の
符号で、６はシール、９は圧力調整弁、１０は反応圧力
容器３′の内圧を測定する圧力計であり、加熱体４を大
気から遮断して不活性ガスで蔽う保護容器４ａが設けら
れている。The zero reaction pressure vessel 3' is heated by a heating element 4 to a doping treatment temperature. A doping gas such as SFb, CF4, C in the case of fluorine is introduced into the reaction pressure vessel 3'.
2F4. SiF<, B7, 5izF6, etc. are supplied under pressure to about 4 atmospheres. Such a doping gas is supplied from the gas supply lower at the lower end of the reaction pressure vessel 3', and is discharged from the gas outlet 8 at the upper end. In addition, in the symbols in the figure, 6 is a seal, 9 is a pressure regulating valve, and 10 is a pressure gauge for measuring the internal pressure of the reaction pressure vessel 3'.The heating element 4 is protected from the atmosphere and covered with inert gas. A container 4a is provided.
〈発明が解決しようとする問題点〉
第２図に示した従来の多孔質光ファイバ母材のドーピン
グ処理装置では、反応圧力容器３′を１０００″近い高
温と数気圧の内圧とに耐えるように設計しなければなら
ない。反応圧力容ｉ１Ｂ ３ｒとして石英又は酸化アル
ミニウムを用いる場合は、内圧に耐えられるような構造
的強度を保つため、相当に厚肉のものを使用する必要が
ある。従ってこのような反応圧力容器３′は品温高圧下
で使用されるため、絶えず破裂の心配があり、取扱いに
は極めて注意を要する。また、容器も非常に高価になる
。<Problems to be Solved by the Invention> In the conventional doping treatment apparatus for a porous optical fiber base material shown in FIG. When using quartz or aluminum oxide as the reaction pressure volume i1B 3r, it is necessary to use a material with a considerably thick wall to maintain the structural strength to withstand the internal pressure. Since the reaction pressure vessel 3' is used at high temperature and pressure, there is a constant fear of rupture and must be handled with great care.The vessel is also very expensive.
一方、金属の反応圧力容器３′を使用する場合は、多孔
質光ファイバ母材が反応圧力容器３′を構成する金属に
汚染され易く、良質の光ファイバを得ることができない
、更に、ドーピングガスは一般に腐食性が強くて金属製
の反応圧力容器３′では短期間に消損して使用不能にな
る欠点があった。On the other hand, when using a metal reaction pressure vessel 3', the porous optical fiber base material is easily contaminated by the metal constituting the reaction pressure vessel 3', making it impossible to obtain a high quality optical fiber. Generally, they are highly corrosive and have the drawback that they are consumed in a short period of time and become unusable in the metal reaction pressure vessel 3'.
本発明はかかる従来技術の欠点に鑑みてなされたもので
、薄肉の石英又は酸化アルミニウムの反応容器を用いる
ことが可能な多孔質光ファイバ母材のドーピング処理装
置を提０（することを目的とする。The present invention has been made in view of the drawbacks of the prior art, and aims to provide a doping treatment apparatus for a porous optical fiber base material that can use a thin-walled quartz or aluminum oxide reaction vessel. do.
く問題点を解決するための手段〉
本発明による多孔質光ファイバ母材のドーピング処理装
置は、多孔質光ファイバ母材を収容してこの多孔質光フ
ァイバ母材にドーパントを含浸させる反応容器と、該反
応容器内に前記ドーパントを含むドーピングガスを加圧
状態で送給するドーピングガス供給手段と、前記反応容
器内を加熱する加熱体と、この加熱体と前記反応容器と
を収容する圧力容器と、この圧力容器内に加圧状態の不
活性ガスを送給する不活性ガス供給手段と、前記圧力容
器内のガス圧と上記反応容器内のガス圧との圧力差を一
定に制御する圧力調整装置とを具えたことを特徴とする
ものである。Means for Solving the Problems> A doping treatment apparatus for a porous optical fiber preform according to the present invention comprises a reaction vessel for accommodating a porous optical fiber preform and impregnating the porous optical fiber preform with a dopant. , a doping gas supply means for feeding a doping gas containing the dopant into the reaction vessel under pressure, a heating body for heating the inside of the reaction vessel, and a pressure vessel housing the heating body and the reaction vessel. , an inert gas supply means for supplying pressurized inert gas into the pressure vessel, and a pressure for controlling the pressure difference between the gas pressure in the pressure vessel and the gas pressure in the reaction vessel to be constant. The invention is characterized in that it includes an adjustment device.
く作 用〉
多孔質光ファイバ母材を収容する反応容器の内圧と、こ
の反応容器と反応容器を加熱する加熱体とを収容する圧
力容器の内圧とを圧力ＩＪＲ整装置によって自動的にほ
ぼ等しく保っており、反応容器の内外で大きな圧力差が
発生しない。Function> The pressure IJR adjustment device automatically equalizes the internal pressure of the reaction vessel that houses the porous optical fiber preform and the internal pressure of the pressure vessel that houses the reaction vessel and the heating element that heats the reaction vessel. The pressure difference between the inside and outside of the reaction vessel does not occur.
〈実 施 例〉
本発明による多孔質光ファイバ母材のドーピング処理装
置の一実施例の概略構造を表す第１図に示すように、多
孔質光ファイバ母材２は支持棒ｌによって回転可能に支
持され、反応容器３の中央部に挿入されている。反応容
器３へは加圧されたドーピングガス、例えば弗素系では
ＳＦａ 、 ＣＦａ ｒ ＣｚＦ＆、 Ｓｒ’ｓ、 Ｂ
ＦＩ。<Embodiment> As shown in FIG. 1, which shows a schematic structure of an embodiment of the doping treatment apparatus for a porous optical fiber preform according to the present invention, a porous optical fiber preform 2 is rotatable by a support rod l. It is supported and inserted into the center of the reaction vessel 3. A pressurized doping gas, for example, SFa, CFa, CzF&, Sr's, B in the case of fluorine, is supplied to the reaction vessel 3.
FI.
ＳｉＦ６等が供給ロアから供給されると共に排出口８か
ら排出され、反応容器３内ではドーピングガスは圧力調
整弁９の調整で所望の気圧に保たれている。また、加熱
体４は反応容器３を取り巻いており反応容器３内を所望
の処理温度、例えば８００℃以上に加熱している。SiF6 and the like are supplied from the supply lower and discharged from the discharge port 8, and the doping gas is maintained at a desired pressure inside the reaction vessel 3 by adjusting the pressure regulating valve 9. Further, the heating body 4 surrounds the reaction vessel 3 and heats the inside of the reaction vessel 3 to a desired processing temperature, for example, 800° C. or higher.
この加熱によって反応容器３内ではドーピングガス中の
ドーパント、例えば弗素系ガスでは弗素成分が多孔質光
ファイバ母材２に効果的に含浸されて行く。反応容器３
と加熱体４とは鋼製等の圧力容器５で囲まれており、圧
力容器５内へは不活性ガスが配管１３及び圧力制御弁１
４を経て供給される。制御装置１２には反応容器３０内
の気圧を計４１すする圧力計１０及び圧力容器５内の気
圧を計測する圧力計１１からの圧力情報が大ツノされ、
圧力容器５へ流入する不活性ガスの流量を、圧力容器５
内の圧力が反応容器３内の圧力と等しいか或いは水柱で
数ミリメートル程度大となるように、配管１３に装置さ
れた圧力制御弁１４を介して制御している。尚、図中の
符号で６は反応容器３０の気密性を高めるシールである
。By this heating, the dopant in the doping gas, for example, a fluorine component in the case of a fluorine-based gas, is effectively impregnated into the porous optical fiber base material 2 in the reaction vessel 3. Reaction vessel 3
The heating body 4 is surrounded by a pressure vessel 5 made of steel or the like, and an inert gas is supplied into the pressure vessel 5 through a pipe 13 and a pressure control valve 1.
4. The control device 12 receives pressure information from a pressure gauge 10 measuring the atmospheric pressure inside the reaction vessel 30 and a pressure gauge 11 measuring the atmospheric pressure inside the pressure vessel 5.
The flow rate of the inert gas flowing into the pressure vessel 5 is
The pressure inside the reaction vessel 3 is controlled via a pressure control valve 14 installed in the piping 13 so that it is equal to the pressure inside the reaction vessel 3 or approximately several millimeters higher in water column. Note that the reference numeral 6 in the figure is a seal that increases the airtightness of the reaction container 30.
従って、反応容器３の内外圧を、圧力計１０゜１１及び
制御装置１２及び圧力制御弁１４からなる圧力調整装置
によって自動的にほぼ等しく保っている。このため、反
応容器３には圧力が殆んど作用せず、比較的薄い石英や
酸化アルミニウムといった材料で反応容器３を形成する
ことができる０反応容器３は上述した理由から薄肉でも
破裂する心配がなく、多孔質光ファイバ母材２に急速に
ドーピングガスの中のドーパント成分を加圧した状態で
ドープすることができる。Therefore, the internal and external pressures of the reaction vessel 3 are automatically maintained approximately equal by a pressure regulating device comprising a pressure gauge 10.degree. 11, a control device 12, and a pressure control valve 14. For this reason, almost no pressure acts on the reaction vessel 3, and the reaction vessel 3 can be made of relatively thin materials such as quartz or aluminum oxide.For the reasons mentioned above, there is no risk of the reaction vessel 3 bursting even with a thin wall. Therefore, the porous optical fiber preform 2 can be rapidly doped with the dopant component in the doping gas under pressure.
〈発明の効果〉
本発明の多孔質光ファイバ母材のドーピング処理装置に
よれば、反応容器を反応容器内の加圧されたドーピング
ガスの圧力とほぼ等しい圧力に保たれた圧力容器内に収
容することによって、反応容器を石英或いは酸化アルミ
ニウム等の如き光ファイバを汚染しない薄肉材料で形成
できる。従って、反応容器のコストを著しく削減でき、
装置全体のコストを低下させることができた。また、従
来のものの如く反応容器が内圧のために破裂するといっ
た心配はなくなり、長期間に互って安全に使用できる上
に高い生産性で純度の高い光ファイバ母材を得ることが
できるようになった。<Effects of the Invention> According to the doping treatment apparatus for a porous optical fiber preform of the present invention, the reaction vessel is housed in a pressure vessel maintained at a pressure approximately equal to the pressure of the pressurized doping gas in the reaction vessel. By doing so, the reaction vessel can be made of a thin material such as quartz or aluminum oxide that does not contaminate the optical fiber. Therefore, the cost of reaction vessels can be significantly reduced,
The cost of the entire device could be reduced. In addition, there is no need to worry about the reaction vessel bursting due to internal pressure as in conventional systems, and it is now possible to safely use each other for a long period of time, and to obtain high-purity optical fiber preforms with high productivity. became.
第１図は本発明による多孔質光ファイバ母材のドーピン
グ処理装置の一実施例の構造を表す断面図、第２図は従
来の多孔質光ファイバ母１オのドーピング処理装置の一
例を表す断面図である。
図面中、ｌは支持棒、２は多孔質光ファイバ母材、３は
反応容器、４は加熱体、５は圧力容器、７はガス供給口
、８はガス排気口、９は圧力調整弁、１２は制御装置、
１３はガス供給口、１４は圧力制御弁である。FIG. 1 is a cross-sectional view showing the structure of an embodiment of a doping processing apparatus for a porous optical fiber preform according to the present invention, and FIG. 2 is a cross-sectional view showing an example of a conventional doping processing apparatus for a porous optical fiber preform. It is a diagram. In the drawings, l is a support rod, 2 is a porous optical fiber preform, 3 is a reaction vessel, 4 is a heating element, 5 is a pressure vessel, 7 is a gas supply port, 8 is a gas exhaust port, 9 is a pressure regulating valve, 12 is a control device;
13 is a gas supply port, and 14 is a pressure control valve.
Claims (2)
ァイバ母材にドーパントを含浸させる反応容器と、該反
応容器内に前記ドーパントを含むドーピングガスを加圧
状態で送給するドーピングガス供給手段と、前記反応容
器内を加熱する加熱体と、この加熱体と前記反応容器と
を収容する圧力容器と、この圧力容器内に加圧状態の不
活性ガスを送給する不活性ガス供給手段と、前記圧力容
器内のガス圧と上記反応容器内のガス圧との圧力差を制
御する圧力調整装置とを具えたことを特徴とする多孔質
光ファイバ母材のドーピング処理装置。(1) A reaction vessel that accommodates a porous optical fiber preform and impregnates the porous optical fiber preform with a dopant, and a doping gas that supplies the doping gas containing the dopant under pressure into the reaction vessel. a supply means, a heating body for heating the inside of the reaction vessel, a pressure vessel for accommodating the heating body and the reaction vessel, and an inert gas supply for feeding pressurized inert gas into the pressure vessel. 1. An apparatus for doping a porous optical fiber preform, comprising: means for controlling the pressure difference between the gas pressure in the pressure vessel and the gas pressure in the reaction vessel.
ていることを特徴とする特許請求の範囲第１項に記載し
た多孔質光ファイバ母材のドーピング処理装置。(2) The doping treatment apparatus for a porous optical fiber preform as set forth in claim 1, wherein the reaction vessel is made of quartz or aluminum oxide.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5909486A JPS62216934A (en) | 1986-03-19 | 1986-03-19 | Device for doping treatment of porous base material for optical fiber |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5909486A JPS62216934A (en) | 1986-03-19 | 1986-03-19 | Device for doping treatment of porous base material for optical fiber |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS62216934A true JPS62216934A (en) | 1987-09-24 |
Family
ID=13103401
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP5909486A Pending JPS62216934A (en) | 1986-03-19 | 1986-03-19 | Device for doping treatment of porous base material for optical fiber |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS62216934A (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5145507A (en) * | 1985-03-18 | 1992-09-08 | Sumitomo Electric Industries, Ltd. | Method for producing glass preform for optical fiber |
| US5203899A (en) * | 1985-03-18 | 1993-04-20 | Sumitomo Electric Industries, Ltd. | Method for producing glass preform for optical fiber |
| US5364428A (en) * | 1985-03-18 | 1994-11-15 | Sumitomo Electric Industries, Ltd. | Method for producing glass preform for optical fiber |
| JP2007051020A (en) * | 2005-08-17 | 2007-03-01 | Asahi Glass Co Ltd | Method and apparatus for treating porous glass |
| KR101310761B1 (en) * | 2012-04-23 | 2013-09-25 | 한국광기술원 | Apparatus for adding doping solution for optical fiber core |
| WO2020251798A1 (en) * | 2019-06-11 | 2020-12-17 | Corning Incorporated | Apparatuses and methods for processing optical fiber preforms |
-
1986
- 1986-03-19 JP JP5909486A patent/JPS62216934A/en active Pending
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5145507A (en) * | 1985-03-18 | 1992-09-08 | Sumitomo Electric Industries, Ltd. | Method for producing glass preform for optical fiber |
| US5203899A (en) * | 1985-03-18 | 1993-04-20 | Sumitomo Electric Industries, Ltd. | Method for producing glass preform for optical fiber |
| US5364428A (en) * | 1985-03-18 | 1994-11-15 | Sumitomo Electric Industries, Ltd. | Method for producing glass preform for optical fiber |
| JP2007051020A (en) * | 2005-08-17 | 2007-03-01 | Asahi Glass Co Ltd | Method and apparatus for treating porous glass |
| JP4666253B2 (en) * | 2005-08-17 | 2011-04-06 | 旭硝子株式会社 | Method for processing porous glass |
| KR101310761B1 (en) * | 2012-04-23 | 2013-09-25 | 한국광기술원 | Apparatus for adding doping solution for optical fiber core |
| WO2020251798A1 (en) * | 2019-06-11 | 2020-12-17 | Corning Incorporated | Apparatuses and methods for processing optical fiber preforms |
| US11554981B2 (en) | 2019-06-11 | 2023-01-17 | Corning Incorporated | Apparatuses and methods for processing optical fiber preforms |
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