JPH0660032B2 - Optical fiber base material manufacturing equipment - Google Patents
Optical fiber base material manufacturing equipmentInfo
- Publication number
- JPH0660032B2 JPH0660032B2 JP992687A JP992687A JPH0660032B2 JP H0660032 B2 JPH0660032 B2 JP H0660032B2 JP 992687 A JP992687 A JP 992687A JP 992687 A JP992687 A JP 992687A JP H0660032 B2 JPH0660032 B2 JP H0660032B2
- Authority
- JP
- Japan
- Prior art keywords
- glass rod
- optical fiber
- glass
- preheating
- burner
- 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
- 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]
- C03B37/0148—Means for heating preforms during or immediately prior to deposition
-
- 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
-
- 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
- C03B2207/54—Multiple burner arrangements combined with means for heating the deposit, e.g. non-deposition burner
-
- 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
- C03B2207/62—Distance
-
- 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
- C03B2207/64—Angle
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母材製造装置に係り、特にガラス棒
を増径加工して母材を製造する装置に関するものであ
る。Description: TECHNICAL FIELD The present invention relates to an optical fiber preform manufacturing apparatus, and more particularly to an apparatus for manufacturing a preform by increasing the diameter of a glass rod.
［従来の技術］ 従来、シングルモード光ファイバは次のようにして製造
されていた。すなわち、まずコア径／クラッド径を1/4
〜1/6 程度に設定してクラッド付コアガラス棒を作製
し、このガラス棒の外周部にさらにクラッド用スート層
を堆積して増径した後、これを透明ガラス化する方法で
ある。[Prior Art] Conventionally, a single-mode optical fiber has been manufactured as follows. In other words, first, the core diameter / clad diameter is 1/4
It is a method in which a core glass rod with a clad is produced by setting it to about 1/6, and a soot layer for clad is further deposited on the outer peripheral portion of the glass rod to increase the diameter thereof, and then this is made into a transparent vitrification.
ところで、このようなシングルモード光ファイバではそ
のコア及びクラッド共に高純度であることが望まれてい
るが、上述したガラス棒の増径加工の際ガラス棒とその
外周部に形成されたスート層との界面（以下、外付界面
と称する）に気泡が発生しやすいという問題があった。By the way, in such a single mode optical fiber, it is desired that both the core and the clad have high purity, but when the glass rod is increased in diameter as described above, the glass rod and the soot layer formed on the outer peripheral portion of the glass rod are used. There is a problem that bubbles are likely to be generated at the interface (hereinafter, referred to as an external interface).
そこで、これを解消するためにスート層の堆積直前にガ
ラス棒を予熱バーナにより予熱するといった提案が特開
昭60−264338号公報になされた。この提案によれば、ガ
ラス棒が予熱されているのでガラス棒に対するスートの
付着が良好となり、気泡の発生が抑制される。Then, in order to solve this, a proposal of preheating a glass rod by a preheating burner immediately before deposition of a soot layer was made in Japanese Patent Laid-Open No. 264338/1985. According to this proposal, since the glass rod is preheated, the soot adheres well to the glass rod and the generation of bubbles is suppressed.
［発明が解決しようとする問題点］ しかしながら、この方法においても反応容器内に浮遊し
たスートや微細な塵がガラス棒の表面に付着することが
多く、これが起因して外付界面に気泡が発生するという
問題があった。この気泡は線引による光ファイバ化にお
いて光ファイバの強度を劣化させる要因となるものであ
る。[Problems to be Solved by the Invention] However, also in this method, soot and fine dust floating in the reaction vessel are often attached to the surface of the glass rod, which causes bubbles at the external interface. There was a problem of doing. This bubble becomes a factor that deteriorates the strength of the optical fiber when it is made into an optical fiber by drawing.
さらに、ガラス棒を予熱バーナで予熱することによりガ
ラス棒の表面からその内部に水分が侵入し、その結果光
ファイバの伝送損失が大きくなるという問題もあった。Further, there is a problem that preheating the glass rod with a preheating burner causes moisture to penetrate from the surface of the glass rod into the inside thereof, resulting in a large transmission loss of the optical fiber.
かくして本発明の目的は上記従来技術の問題点を解消
し、高強度で且つ伝送特性の優れた光ファイバを得るこ
とができる光ファイバ母材製造装置を提供することにあ
る。Thus, an object of the present invention is to solve the above-mentioned problems of the prior art and to provide an optical fiber preform manufacturing apparatus capable of obtaining an optical fiber having high strength and excellent transmission characteristics.
［問題点を解決するための手段］ 上記目的を達成するために第１の発明に係る光ファイバ
母材製造装置は、鉛直に配置されたガラス棒を回転上昇
させると共に上記ガラス棒の外周部にガラス生成用バー
ナにより生成されたスートを堆積する光ファイバ母材製
造装置において、上記ガラス生成用バーナの下方に設け
られると共に上記ガラス棒を予熱するための予熱用バー
ナと、該予熱用バーナからの火炎が当たる位置から下側
の上記ガラス棒を内挿すべくその上端が開放され且つ鉛
直に設けられた保護管と、該保護管内に上方に向けて不
活性ガスを供給するガス供給手段とを備えたものであ
る。[Means for Solving the Problems] In order to achieve the above object, the optical fiber preform manufacturing apparatus according to the first aspect of the present invention rotates a glass rod arranged vertically and raises it at the outer peripheral portion of the glass rod. In an optical fiber preform manufacturing apparatus for depositing soot produced by a glass producing burner, a preheating burner for preheating the glass rod provided under the glass producing burner and a preheating burner for preheating the glass rod. The protective tube is provided with its upper end opened vertically to insert the lower glass rod from the position where the flame hits, and a gas supply means for supplying an inert gas upward into the protective tube. It is a thing.
また、第２の発明に係る光ファイバ母材製造装置は、鉛
直に配置されたガラス棒を回転上昇させると共に上記ガ
ラス棒の外周部にガラス生成用バーナにより生成された
スートを堆積する光ファイバ母材製造装置において、上
記ガラス生成用バーナの下方に設けられると共に上記ガ
ラス棒を予熱するための予熱用バーナと、該予熱用バー
ナからの火炎が当たる位置から下側の上記ガラス棒を内
挿すべくその上端が開放され且つ鉛直に設けられた保護
管と、該保護管内に上方に向けて塩素ガスあるいはガラ
ス原料とならない塩素化合物ガスを供給するガス供給手
段とを備えたものである。An optical fiber preform manufacturing apparatus according to a second aspect of the present invention is an optical fiber preform for rotating and vertically raising a vertically arranged glass rod and depositing soot generated by a glass generation burner on an outer peripheral portion of the glass rod. In a material manufacturing apparatus, a preheating burner for preheating the glass rod, which is provided below the glass production burner, and the lower glass rod to be inserted from the position where the flame from the preheating burner hits The protective tube is provided with its upper end opened and provided vertically, and a gas supply means for supplying chlorine gas or a chlorine compound gas which is not a glass raw material upward into the protective tube.
［作 用］ 以上のような構成とすることにより、ガラス棒は予熱直
前まで保護管内に挿入保護され、その後保護管の上部開
口端から放出される不活性ガスあるいは塩素ガスあるい
はガラス原料とならない塩素化合物ガスの雰囲気中にお
いて予熱用バーナにより予熱されてからガラス生成用バ
ーナによってスートの堆積が行なわれることとなる。従
って、予熱前及び予熱中においても反応容器内で発生し
た浮遊スートや塵のガラス棒への付着が防止される。[Operation] With the above configuration, the glass rod is inserted and protected in the protective tube until just before preheating, and then the inert gas or chlorine gas released from the upper open end of the protective tube or chlorine that does not become a glass raw material. The soot is deposited by the glass forming burner after being preheated by the preheating burner in the atmosphere of the compound gas. Therefore, even before and during preheating, floating soot and dust generated in the reaction vessel are prevented from adhering to the glass rod.
また、第２の発明のようにガス供給手段が保護管内に塩
素ガスあるいはガラス原料とならない塩素化合物ガスを
投入することにより、さらにガラス棒内への水分の侵入
が阻止され、これにより低OH基化が図られる。Further, as in the second aspect of the present invention, when the gas supply means introduces chlorine gas or a chlorine compound gas that does not serve as a glass raw material into the protective tube, further invasion of water into the glass rod is prevented, which results in a low OH group. Be promoted.
［実施例］ 以下、本発明の実施例を添付図面に従って説明する。EXAMPLES Examples of the present invention will be described below with reference to the accompanying drawings.
実施例１ 添付図は本発明の一実施例に係る光ファイバ母材製造装
置の構成を示す断面図である。反応容器１の側面部に予
熱用バーナ２とガラス生成用バーナ３及び４とが順次下
から鉛直方向に配列されており、これらバーナに対向し
て排気管５が設けられている。また、反応容器１の底部
には石英ガラス製の内径30mmの保護管６が鉛直に設けら
れている。この保護管６の上端部は開放されており、下
端部には供給管７を介してガス供給装置８が接続されて
いる。Example 1 The attached drawings are sectional views showing the configuration of an optical fiber preform manufacturing apparatus according to an example of the present invention. A preheating burner 2 and glass forming burners 3 and 4 are sequentially arranged in the vertical direction from the bottom on the side surface of the reaction vessel 1, and an exhaust pipe 5 is provided so as to face these burners. A protective tube 6 made of quartz glass and having an inner diameter of 30 mm is vertically provided at the bottom of the reaction vessel 1. The upper end of the protection pipe 6 is open, and the lower end is connected to a gas supply device 8 via a supply pipe 7.
なお、予熱用バーナ２及びガラス生成用バーナ３は共に
四重管構造を、ガラス生成用バーナ４は九重管構造をそ
れぞれ有している。また、各バーナ２〜４の反応容器１
の鉛直軸９に対する噴射角θ１〜θ３はそれぞれ70゜と
し、各バーナ２〜４の先端から鉛直軸９までの距離ｌ１
〜ｌ３をそれぞれｌ１＝40mm，ｌ２＝70mm，ｌ３＝ 100
mmに設定した。Both the preheating burner 2 and the glass-producing burner 3 have a quadruple tube structure, and the glass-producing burner 4 has a nine-fold tube structure. Also, the reaction vessel 1 of each burner 2-4
The injection angles θ 1 to θ 3 with respect to the vertical axis 9 are 70 °, and the distance l 1 from the tip of each burner 2 to 4 to the vertical axis 9 is 1.
~ L 3 are respectively l 1 = 40 mm, l 2 = 70 mm, l 3 = 100
set to mm.
このような装置を用いて母材の製造を行なった。The base material was manufactured using such an apparatus.
まず、ガラス棒１０を反応容器１の鉛直軸９に沿って導
入し、その下端部を保護管６内に挿入する。ここで、ガ
ラス棒１０としては、GeO2−SiO2（△＝0.33％）からな
るコア用ガラスとSiO2からなるクラッド用ガラスとを有
するクラッド径／コア径＝６のガラス棒を予め加熱延伸
して直径20mmに減径したものを用いている。First, the glass rod 10 is introduced along the vertical axis 9 of the reaction vessel 1, and the lower end portion thereof is inserted into the protective tube 6. Here, as the glass rod 10, a glass rod having a clad diameter / core diameter = 6 having a core glass made of GeO 2 —SiO 2 (Δ = 0.33%) and a clad glass made of SiO 2 is preheated and drawn. The diameter is reduced to 20 mm.
そして、ガス供給装置８から流量10/minのN2ガスを保
護管６内に供給すると共に予熱用バーナ２から予熱用火
炎を形成させる一方、ガラス生成用バーナ３及び４から
ガラス原料を噴出してこれを火炎加水分解反応させ、ス
ートを生成させる。また、反応容器１内の排気圧を− 4
mmH2O として排気管５より排気し、この状態でガラス棒
１０を回転させつつ引上速度60mm/hで引上げる。すなわ
ち、ガラス棒１０は保護管６の上端部のすぐ上方でN2雰
囲気中において予熱用バーナ２により予熱された後、さ
らにその外周部にガラス生成用バーナ３及び４によって
生成されたスートが堆積される。Then, while supplying N 2 gas at a flow rate of 10 / min from the gas supply device 8 into the protective tube 6 and forming a preheating flame from the preheating burner 2, the glass raw materials are jetted from the glass production burners 3 and 4. This causes flame hydrolysis reaction to generate soot. Moreover, the exhaust pressure in the reaction vessel 1 is set to −4.
The gas is exhausted from the exhaust pipe 5 as mmH 2 O, and in this state, the glass rod 10 is rotated and pulled up at a pulling rate of 60 mm / h. That is, the glass rod 10 is preheated by the preheating burner 2 in the N 2 atmosphere just above the upper end portion of the protection tube 6, and then the soot generated by the glass generation burners 3 and 4 is further accumulated on the outer peripheral portion thereof. To be done.
このようにして、ガラス棒１０の外周部に直径 100mmの
スート層１１を形成した。さらに、これをHe及びCl２混
合の雰囲気中で電気炉（図示せず）により透明ガラス化
し、直径40mmの光ファイバ母材を得た。Thus, the soot layer 11 having a diameter of 100 mm was formed on the outer peripheral portion of the glass rod 10. Further, this was made into transparent glass by an electric furnace (not shown) in an atmosphere of a mixture of He and Cl 2 to obtain an optical fiber preform with a diameter of 40 mm.
この光ファイバ母材の外付界面を観察したところ、気泡
の発生は全く見られなかった。Observation of the external interface of this optical fiber preform showed no generation of bubbles.
なお、保護管６内に供給したガスはN2ガスに限るもので
はなく、He，Ar等の他の不活性ガスを用いても同様の効
果が得られる。The gas supplied into the protective tube 6 is not limited to the N 2 gas, and the same effect can be obtained by using another inert gas such as He or Ar.
実施例２ 添付図のガス供給装置８として流量 1/minの塩素ガス
を供給する装置を用いた他は上記実施例１と同様にして
光ファイバ母材の製造を行なった。ただし、ガラス棒１
０は直径20mmに減径した後、その外周面に存在する高OH
基含有部をHFによりエッチングしてからスートの堆積を
行なった。Example 2 An optical fiber preform was manufactured in the same manner as in Example 1 except that a chlorine gas supply device having a flow rate of 1 / min was used as the gas supply device 8 in the attached drawing. However, 1 glass rod
0 is high OH existing on the outer peripheral surface after the diameter is reduced to 20 mm.
The soot was deposited after etching the base-containing part with HF.
そして製造された光ファイバ母材の外付界面を観察した
ところ、気泡の発生は全く見られなかった。When the outer interface of the manufactured optical fiber preform was observed, no bubbles were found.
さらに、この光ファイバ母材をファイバ化してシングル
モード光ファイバを作製しその伝送特性を測定したとこ
ろ、波長 1.39 μｍでのOH基吸収損失が最大 0.5dB／mm
以下と極めて優れた特性を示した。すなわち、この実施
例２で製造された光ファイバ母材は低OH基化が達成され
ていることが確認された。Furthermore, the optical fiber base material was made into a fiber to fabricate a single mode optical fiber, and its transmission characteristics were measured. The OH group absorption loss at a wavelength of 1.39 μm was 0.5 dB / mm at maximum.
The following excellent characteristics were shown. That is, it was confirmed that the optical fiber preform manufactured in Example 2 achieved low OH grouping.
なお、塩素ガスの他、ガラス原料とならないSOCl２，CC
l４，CCl2F２等の塩素化合物ガスを用いても同様の効果
が得られる。In addition to chlorine gas, SOCl 2 , CC that is not a glass raw material
The same effect can be obtained by using a chlorine compound gas such as l 4 and CCl 2 F 2 .
また、上記実施例１及び２における保護管６としては耐
熱ガラスあるいはセラミックスから構成することもでき
る。Further, the protective tube 6 in Examples 1 and 2 may be made of heat-resistant glass or ceramics.
［発明の効果］ 以上説明したように本発明によれば、次の如き優れた効
果が発揮される。[Effects of the Invention] As described above, according to the present invention, the following excellent effects are exhibited.
(1) 反応容器内で発生する浮遊スートや塵のガラス棒
外周部への付着が防止され、気泡を含まない光ファイバ
母材が得られる。その結果、高強度の光ファイバを製造
することができるようになる。(1) Floating soot and dust generated in the reaction vessel are prevented from adhering to the outer periphery of the glass rod, and an optical fiber preform containing no bubbles can be obtained. As a result, it becomes possible to manufacture a high-strength optical fiber.
(2) 保護管内に塩素ガスあるいはガラス原料とならな
い塩素化合物ガスを供給することにより、ガラス棒内へ
の水分の侵入を阻止してOH基含有量の極めて小さい光フ
ァイバ母材が得られる。その結果、伝送特性の優れた光
ファイバを製造することができる。(2) By supplying chlorine gas or a chlorine compound gas that does not serve as a glass raw material into the protective tube, it is possible to prevent the intrusion of water into the glass rod and obtain an optical fiber preform having an extremely small OH group content. As a result, it is possible to manufacture an optical fiber having excellent transmission characteristics.
添付図は本発明の一実施例に係る光ファイバ母材製造装
置の構成を示す断面図である。 図中、２は予熱用バーナ、３及び４はガラス生成用バー
ナ、６は保護管、７は供給管、８はガス供給装置、１０
はガラス棒、１１はスート層である。The attached drawing is a sectional view showing the construction of an optical fiber preform manufacturing apparatus according to an embodiment of the present invention. In the figure, 2 is a preheating burner, 3 and 4 are glass generating burners, 6 is a protective tube, 7 is a supply tube, 8 is a gas supply device, 10
Is a glass rod, and 11 is a soot layer.
Claims (2)
ると共に上記ガラス棒の外周部にガラス生成用バーナに
より生成されたスートを堆積する光ファイバ母材製造装
置において、上記ガラス生成用バーナの下方に設けられ
ると共に上記ガラス棒を予熱するための予熱用バーナ
と、該予熱用バーナからの火炎が当たる位置から下側の
上記ガラス棒を内挿すべくその上端が開放され且つ鉛直
に設けられた保護管と、該保護管内に上方に向けて不活
性ガスを供給するガス供給手段とを備えたことを特徴と
する光ファイバ母材製造装置。1. An optical fiber preform manufacturing apparatus for rotating and vertically raising a glass rod arranged vertically and depositing soot generated by a glass-forming burner on the outer peripheral portion of the glass rod, wherein A preheating burner for preheating the glass rod, which is provided below, and an upper end thereof is opened and vertically provided so that the lower glass rod is inserted from a position hit by a flame from the preheating burner. An optical fiber preform manufacturing apparatus comprising: a protective tube; and gas supply means for supplying an inert gas upward into the protective tube.
ると共に上記ガラス棒の外周部にガラス生成用バーナに
より生成されたスートを堆積する光ファイバ母材製造装
置において、上記ガラス生成用バーナの下方に設けられ
ると共に上記ガラス棒を予熱するための予熱用バーナ
と、該予熱用バーナからの火炎が当たる位置から下側の
上記ガラス棒を内挿すべくその上端が開放され且つ鉛直
に設けられた保護管と、該保護管内に上方に向けて塩素
ガスあるいはガラス原料とならない塩素化合物ガスを供
給するガス供給手段とを備えたことを特徴とする光ファ
イバ母材製造装置。2. An optical fiber preform manufacturing apparatus for rotating and vertically raising a vertically arranged glass rod and depositing soot produced by a glass producing burner on an outer peripheral portion of the glass rod, A preheating burner for preheating the glass rod, which is provided below, and an upper end thereof is opened and vertically provided so that the lower glass rod is inserted from a position hit by a flame from the preheating burner. An optical fiber preform manufacturing apparatus comprising: a protection tube; and a gas supply means for supplying chlorine gas or a chlorine compound gas that does not become a glass raw material upward into the protection tube.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP992687A JPH0660032B2 (en) | 1987-01-21 | 1987-01-21 | Optical fiber base material manufacturing equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP992687A JPH0660032B2 (en) | 1987-01-21 | 1987-01-21 | Optical fiber base material manufacturing equipment |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63182232A JPS63182232A (en) | 1988-07-27 |
| JPH0660032B2 true JPH0660032B2 (en) | 1994-08-10 |
Family
ID=11733684
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP992687A Expired - Lifetime JPH0660032B2 (en) | 1987-01-21 | 1987-01-21 | Optical fiber base material manufacturing equipment |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0660032B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA2125508C (en) * | 1993-06-16 | 2004-06-08 | Shinji Ishikawa | Process for producing glass preform for optical fiber |
| JP4813869B2 (en) | 2004-11-09 | 2011-11-09 | 臼井国際産業株式会社 | Externally controlled fan coupling device |
-
1987
- 1987-01-21 JP JP992687A patent/JPH0660032B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPS63182232A (en) | 1988-07-27 |
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