JP3106564B2 - Manufacturing method of optical fiber and silica-based optical fiber - Google Patents
Manufacturing method of optical fiber and silica-based optical fiberInfo
- Publication number
- JP3106564B2 JP3106564B2 JP18458791A JP18458791A JP3106564B2 JP 3106564 B2 JP3106564 B2 JP 3106564B2 JP 18458791 A JP18458791 A JP 18458791A JP 18458791 A JP18458791 A JP 18458791A JP 3106564 B2 JP3106564 B2 JP 3106564B2
- Authority
- JP
- Japan
- Prior art keywords
- core
- optical fiber
- glass
- preform
- base material
- 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]
- C03B37/01446—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
- C03B2201/20—Doped silica-based glasses doped with non-metals other than boron or 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)
- Glass Compositions (AREA)
Description
【0001】[0001]
【産業上の利用分野】本発明は石英系光ファイバ及びそ
の製造に関するものであり、特に純石英ガラスをコアと
し、フッ素添加石英系ガラスをクラッドとする光ファイ
バの製造に適用してコア内の残留応力を低減して製造で
きる方法に関するものである。The present invention relates is related to the production of silica-based fiber-optic and its <br/>, and in particular the core of pure quartz glass
The present invention also relates to a method for reducing the residual stress in the core by applying the method to the production of an optical fiber having a fluorine-doped quartz glass clad .
【0002】[0002]
【従来の技術】光ファイバ用母材を大量生産する一般的
な方法としてVAD(Vapor Phase Axial Deposition)
法が知られている。VAD法は、回転する出発部材例え
ばガラス棒の上に酸水素火炎中で生成したガラス微粒子
を堆積させて円柱状の多孔質母材を作り、この多孔質母
材を焼結して透明な光ファイバ用ガラス母材を製造する
方法である。VAD法において、多孔質母材を焼結し、
透明ガラス化するには、母材を不活性気体雰囲気中で1
600℃以上に加熱する必要がある。また水分の混入が
あると得られる光ファイバの通信波長域における損失特
性が損なわれるため、通常透明化前または透明化と同時
に多孔質母材を脱水することが行われる。脱水処理とし
て多孔質母材を塩素系ガスを添加した不活性ガス雰囲気
中で高温加熱処理する方法が知られている。2. Description of the Related Art VAD (Vapor Phase Axial Deposition) is a general method for mass producing optical fiber preforms.
The law is known. In the VAD method, glass fine particles generated in an oxyhydrogen flame are deposited on a rotating starting member, for example, a glass rod, to form a cylindrical porous base material, and the porous base material is sintered to form a transparent light source. This is a method for producing a glass preform for fiber. In the VAD method, the porous base material is sintered,
To make the glass transparent, the base material is placed in an inert gas atmosphere for 1 hour.
It is necessary to heat to 600 ° C. or higher. In addition, since the loss characteristic in the communication wavelength region of the obtained optical fiber is impaired if water is mixed, the porous preform is usually dehydrated before or simultaneously with the transparency. As a dehydration treatment, a method is known in which a porous base material is heated at a high temperature in an inert gas atmosphere to which a chlorine-based gas is added.
【0003】[0003]
【発明が解決しようとする課題】ところで、近年特に光
ファイバの低損失化の観点から、コアに純粋石英ガラ
ス、クラッドにフッ素添加石英ガラスを用いたシングル
モードファイバが有望視されている。純粋石英をコアと
する光ファイバは、コアにGeO2 を添加しないことか
ら、散乱損失を低減できて、低損失化には極めて有利で
ある。ところが、純粋石英コア−フッ素添加石英クラッ
ドからなる光ファイバの場合、断面積の小さなコア部の
粘性がクラッド部より大きいため、線引時の張力の大部
分がコアにかかることになる。その結果、ガラス固化時
にはコア部に引張応力が残り、種々の不具合が生じてい
た。つまり引張応力によりコア部の屈折率が低下(光弾
性効果)してコア−クラッド間の比屈折率差が低下する
結果、プリフォームの段階で予想したλc (カットオフ
波長)、MFD(モールドフィールド径)、λ0 (零分
散波長)にずれが生じるとともに、引張応力の残留は製
造条件(線引条件)にも強く依存するため、条件安定化
に非常に注意する必要があった。本発明は、以上のよう
な純粋石英コア−フッ素添加クラッド構造のファイバの
問題点を解決し、設計した構造の光ファイバを製造でき
る方法及び問題点を解決された石英系光ファイバを提供
することを目的としてなされたものである。In recent years, single mode fibers using pure silica glass for the core and fluorine-doped silica glass for the cladding have been considered promising, particularly from the viewpoint of reducing the loss of the optical fiber. An optical fiber having pure silica as a core does not add GeO 2 to the core, so that scattering loss can be reduced, which is extremely advantageous for reducing the loss. However, pure silica core - if the optical fiber made of a fluorine-added silica cladding, the viscosity of the small core portion of the cross-sectional area is larger than that of the clad portion, most of the tension at the time of drawing will be exerted on the core. As a result, during the vitrification, tensile stress remains in the core, causing various problems. That is, the refractive index of the core portion is reduced by the tensile stress (photoelastic effect), and the difference in the relative refractive index between the core and the clad is reduced. As a result, λc (cutoff wavelength) predicted at the preform stage, MFD (mold field) (Diameter) and λ 0 (zero dispersion wavelength), and the residual tensile stress strongly depends on the manufacturing conditions (drawing conditions). Therefore, great care must be taken to stabilize the conditions. The present invention is more pure silica core such as - to solve the problems of fiber fluoridation cladding structure, providing a silica-based optical fibers that have been resolved methods and problems of fiber-optic can be prepared having a structure designed It is done for the purpose of.
【0004】[0004]
【課題を解決するための手段】本発明者らは上述したと
ころに鑑み、コアとなる純粋石英ガラスの粘性を下げる
ことにより、クラッドとなるフッ素添加石英ガラスの粘
性との差を相対的に小さくし、これにより線引時のコア
への応力集中を緩和させようと考え、種々検討の結果、
純粋石英ガラス中に微量のハロゲンを含有させることで
問題が解決できることを見出し、本発明に到達した。す
なわち、上記問題を解決する本発明の製造方法は、石英
を主成分とする多孔質母材を脱水処理および透明ガラス
化してガラス母材とした後に線引して光ファイバを得る
方法において、該脱水処理工程および/又は透明ガラス
化工程においてハロゲン系ガスを含む雰囲気中で加熱処
理することにより石英ガラス中にハロゲンを0.3〜1
重量%含ませ、これにより得られたガラス母材を光ファ
イバのコアとして用い、且つフッ素添加石英系ガラスを
クラッドとして用いることを特徴とする。本発明におい
て石英ガラス中に含有させるハロゲンとしては、塩素が
特に好ましい。また本発明は、コアとフッ素添加石英系
ガラスクラッドを有してなり、かつ該コアは塩素を含む
ハロゲンを0.3〜1重量%含ませた石英ガラスからな
ることを特徴とする石英系光ファイバを提供する。Means for Solving the Problems In view of the above, the present inventors have reduced the viscosity of pure silica glass serving as a core so that the difference between the viscosity of fluorine-doped silica glass serving as a clad and the viscosity thereof can be relatively reduced. We thought that this would reduce the stress concentration on the core during drawing, and as a result of various studies,
The inventors have found that the problem can be solved by adding a trace amount of halogen to pure quartz glass, and have reached the present invention. That is, the manufacturing method of the present invention that solves the above problem is a method of obtaining an optical fiber by drawing a porous preform containing quartz as a main component after dehydration and vitrification into a glass preform to obtain an optical fiber. In the dehydration step and / or the transparent vitrification step, heat treatment is performed in an atmosphere containing a halogen-based gas to reduce the halogen content in the quartz glass to 0.1%. 3 to 1
% By weight, and the obtained glass preform is used as a core of an optical fiber, and a fluorine-containing quartz glass is used as a clad. In the present invention, chlorine is particularly preferable as the halogen contained in the quartz glass. Further, the present invention has a core and a fluorine-containing quartz glass clad, and the core contains 0.1% of halogen containing chlorine. Provided is a silica-based optical fiber comprising silica glass containing 3 to 1% by weight.
【0005】[0005]
【作用】前記した純粋石英ガラスの粘性の影響を調べる
ためにハロゲンとしてはClを代表として用いて、石英
ガラス中のCl量をイオンクロマトグラフ法で分析し、
定量化するとともに、該石英母材をコアとして、シング
ルモードファイバを製造して、構造(λc,MFD),
残留応力及びファイバの屈折率分布からコアとクラッド
の比屈折率差を測定した。Cl量が多くなるにつれ、フ
ァイバ内の残留応力は小さくなり、その結果コアとクラ
ッドと比屈折率差はプリフォーム状態で測定した値に近
づくことが明らかとなった(図1及び図2)。また、フ
ァイバ構造(λc,MFD)もプリフォーム段階での予
測値にほぼ一致した(図3)。以上のことから、純石英
ガラス中のCl量を多くすることにより、石英ガラスの
粘性を下げることができるので、ファイバ構造がプリフ
ォーム段階での予測値からずれることはなくなり、また
線引条件に対する依存性も緩和されることから、純石英
コアシングルモードファイバを製造するのに非常に有効
に作用する。純石英ガラス中のCl量は、0.3重量%
〜1重量%であることが好ましい。0.3重量%未満で
はCl含有の効果が発現せずプリフォーム段階での予測
値から大きくずれるため好ましくない。また、ほぼ1重
量%の含有量でプリフォームの予測値とほぼ一致するの
でこれを越えての含有は不要である。なお、石英ガラス
の粘性を下げる作用を有する他のハロゲン元素の添加の
場合も同様であった。フッ素は屈折率を下げる作用も有
するので、フッ素を添加する場合にはコアへの添加量以
上にクラッドにフッ素を添加する必要がある。その他ヨ
ウ素(I)、臭素(Br)も有効であるが、脱水作用が
一番大きく、屈折率への影響がない点では塩素系ガスを
用いることが有利である。塩素系ガスとしては、例えば
Cl2 、CCl4 、SiCl4 、SOCl2 、SCl2
等を挙げることができる。ただし、例えば脱水処理だけ
塩素系ガスを用いて行い、透明化処理では他のハロゲン
系ガスを用いる、あるいは脱水処理は他のハロゲン系ガ
スを用いて透明化処理は塩素系ガスを用いることも可能
である。In order to investigate the influence of the viscosity of the above-mentioned pure quartz glass, Cl is used as a representative halogen, and the amount of Cl in the quartz glass is analyzed by ion chromatography.
Quantitatively, a single mode fiber was manufactured using the quartz base material as a core, and the structure (λc, MFD),
The relative refractive index difference between the core and the clad was measured from the residual stress and the refractive index distribution of the fiber. It became clear that the residual stress in the fiber decreased as the Cl amount increased, and as a result, the relative refractive index difference between the core and the clad approached the value measured in the preform state (FIGS. 1 and 2). Further, the fiber structure (λc, MFD) almost coincided with the predicted value at the preform stage (FIG. 3). From the above, the viscosity of quartz glass can be reduced by increasing the amount of Cl in pure quartz glass, so that the fiber structure does not deviate from the predicted value at the preform stage, and Since the dependence is also reduced, it is very effective in producing a pure silica core single mode fiber. The amount of Cl in pure quartz glass is 0. 3 % by weight
It is preferably about 1% by weight. If the content is less than 0.3% by weight, the effect of Cl content is not exhibited, and it is not preferable because it largely deviates from the predicted value at the preform stage. Further, since the content of approximately 1% by weight substantially matches the predicted value of the preform, the content beyond this value is unnecessary. The same applies to the case of adding another halogen element having an effect of lowering the viscosity of quartz glass. Since fluorine also has a function of lowering the refractive index, when fluorine is added, it is necessary to add fluorine to the cladding in an amount equal to or more than the amount added to the core. In addition, iodine (I) and bromine (Br) are also effective, but it is advantageous to use a chlorine-based gas in that dehydration is the largest and there is no influence on the refractive index. Examples of the chlorine-based gas include Cl 2 , CCl 4 , SiCl 4 , SOCl 2 , and SCl 2
And the like. However, for example, only dehydration treatment is performed using a chlorine-based gas, and another halogen-based gas is used in the transparency treatment, or another halogen-based gas is used in the dehydration treatment, and a chlorine-based gas is used in the transparency treatment. It is.
【0006】実際に、純石英ガラス中にハロゲンを0.
3重量%〜1重量%の範囲内で含有させるには、ハロゲ
ン化物の中から適当なものを選択し、ハロゲン化物とH
e 等の不活性ガスからなり常圧〜3kg/cm2 程度の
加圧の雰囲気下、温度1000℃〜1700℃の範囲で
加熱して多孔質母材と反応させ、透明ガラス化する。具
体的には、多孔質母材をハロゲン化物ガスを含む雰囲気
中で加熱処理するのは、a)多孔質母材の脱水処理工
程、b)多孔質母材の透明ガラス化処理工程、c)脱水
処理工程および透明ガラス化処理工程、のa)〜c)の
いずれで行ってもよく、特に好ましくはa)又はc)で
ある。添加量の制御は、ガス濃度、処理温度等の調整で
可能であるが、本発明者らの実験では調整の幅はせいぜ
い1.5倍程度までであった。むしろハロゲン化物ガス
の種類の選択の方が添加量の調整には有効であり、例え
ば塩素ガス使用では0.2〜0.4重量%であったの
が、SiCl4 ガスを使用すると0.5〜0.8重量%
となった。つまり、含有量は使用するガス種により大き
く変化させることが可能である。なお、本発明に用いる
多孔質母材としてはこの種の技術分野で公知の手段によ
り作成されたものを用いることができ、例えばVAD
法、OVD法等の気相合成による多孔質母材が挙げられ
るが、これに限定されるものではない。多孔質母材のカ
サ密度も特に限定されるところはないが、一般的には
0.2〜0.4g/cm3 程度である。また、上記説明
では純石英の多孔質体を示したが、石英を主成分とする
多孔質体であればよい。[0006] Actually, halogen is added to pure quartz glass in an amount of 0.1%.
In order to make the content within the range of 3 % by weight to 1% by weight, an appropriate one is selected from the halides,
In an atmosphere consisting of an inert gas such as e and a pressure of normal pressure to about 3 kg / cm 2, it is heated at a temperature in the range of 1000 ° C. to 1700 ° C. to react with the porous base material to form a transparent glass. Specifically, the heat treatment of the porous base material in an atmosphere containing a halide gas includes the following steps: a) a step of dehydrating the porous base material, b) a transparent vitrification step of the porous base material, and c). It may be performed in any of a) to c) of the dehydration treatment step and the transparent vitrification treatment step, and particularly preferably a) or c). The addition amount can be controlled by adjusting the gas concentration, the processing temperature, and the like. However, in experiments performed by the present inventors, the width of the adjustment was at most about 1.5 times. Rather, the choice of the type of halide gas is more effective in adjusting the amount of addition. For example, when chlorine gas was used, the content was 0.2 to 0.4% by weight, but when SiCl 4 gas was used, it was 0.5%. ~ 0.8% by weight
It became. That is, the content can be largely changed depending on the type of gas used. As the porous base material used in the present invention, those prepared by means known in the technical field of this type can be used.
And a porous base material obtained by a gas phase synthesis such as an OVD method. However, the present invention is not limited thereto. Although the bulk density of the porous base material is not particularly limited, it is generally about 0.2 to 0.4 g / cm 3 . In the above description, a porous body made of pure quartz is shown, but any porous body containing quartz as a main component may be used.
【0007】[0007]
【実施例】実施例1 まず図5に示したようにVAD法によって垂直に支持さ
れた出発部材3の下端にバーナ2を対向させ、このバー
ナ2内にSiCl4 1400cc/分を供給し、またH
2 35リットル/分、O2 35リットル/分、Ar10
リットル/分を供給して、SiO2 ガラス微粒子(多孔
質母材)1を出発部材3の下端に堆積させた。得られた
多孔質母材1は直径125mmφ、長さ500mmであ
った。該多孔質母材1を図6に示す炉心管5とヒータ4
を有する焼結炉内に挿入した。密閉系内に挿入された多
孔質母材1は1200℃に維持された炉内にHe10リ
ットル/分、ハロゲン化物ガス(塩素系ガス)としてS
iCl4 200cc/分を供給し、脱水処理した。引き
続き炉温を1600℃に昇温し、He10リットル/
分、SiCl4 200cc/分を供給してコア用透明ガ
ラスロッド(コアロッド)を得た。この母材のCl量を
イオンクロマトグラフ法で分析したところ、0.8重量
%であった。次にこの母材(コアロッド)を直径5mm
に延伸したのち、その周りに外付け法によりSiO2 ガ
ラス微粒子を140mm厚に堆積させた。得られた母材
(コアロッドとガラス微粒子堆積体の複合体)を135
0℃に維持された炉内に挿入し、He 10リットル/
分、SiF4 300cc/分を供給して、フッ素添加し
た後、同雰囲気にて炉温を1550℃に昇温して透明ガ
ラス化した。こうして得られたコア−クラッドを有する
母材(プリフォーム)を外径125μmのファイバに
し、特性を調べた。図4は得られたファイバの屈折率分
布を示す。EXAMPLE 1 First, as shown in FIG. 5, a burner 2 was opposed to a lower end of a starting member 3 vertically supported by the VAD method, and 1400 cc / min of SiCl 4 was supplied into the burner 2. H
2 35 l / min, O 2 35 l / min, Ar10
At a rate of 1 liter / minute, the SiO 2 glass fine particles (porous base material) 1 were deposited on the lower end of the starting member 3. The obtained porous preform 1 had a diameter of 125 mmφ and a length of 500 mm. The porous preform 1 was prepared by using a furnace tube 5 and a heater 4 shown in FIG.
Was inserted into a sintering furnace having The porous preform 1 inserted into the closed system is placed in a furnace maintained at 1200 ° C. as He 10 liter / min. As a halide gas (chlorine-based gas).
Dehydration treatment was performed by supplying 200 cc / min of iCl 4 . Subsequently, the furnace temperature was raised to 1600 ° C., and He 10 liter /
Then, 200 cc / min of SiCl 4 was supplied to obtain a transparent glass rod for core (core rod) . When the Cl content of this base material was analyzed by ion chromatography, it was 0.8% by weight. Next, this base material ( core rod ) is 5 mm in diameter.
After that, SiO 2 glass fine particles were deposited to a thickness of 140 mm therearound by an external method. The obtained base material
(Composite of core rod and glass particle deposit) 135
Inserted in a furnace maintained at 0 ° C., He 10 liters /
After supplying 300 cc / min of SiF 4 and adding fluorine, the furnace temperature was increased to 1550 ° C. in the same atmosphere to form a transparent glass. The base material (preform) having the core-cladding thus obtained was made into a fiber having an outer diameter of 125 μm, and the characteristics were examined. FIG. 4 shows the refractive index distribution of the obtained fiber.
【0008】実施例2 実施例1と同様の方法にて、塩素系ガスとしてCl2 を
用い、純粋石英ガラスロッド(コアロッド)を作成し
た。脱水処理、透明化処理の際の炉内雰囲気はHe 10
リットル/分、Cl2 200cc/分である。この母材
(コアロッド)のCl量は0.3重量%であった。次に
この母材(コアロッド)を直径5mmに延伸したのち、
その周りに外付け法によりSiO2 ガラス微粒子を14
0mm厚に堆積させた。得られた母材(コアロッドとガ
ラス微粒子堆積体の複合体)を1350℃に維持された
炉内に挿入し、He 10リットル/分、SiF4 300
cc/分を供給して、フッ素添加した後、同雰囲気にて
炉温を1550℃に昇温して透明ガラス化した。こうし
て得られたコア−クラッドを有する母材(プリフォー
ム)を外径125μmのファイバにし、特性を調べた。Example 2 In the same manner as in Example 1, a pure silica glass rod (core rod) was prepared using Cl 2 as a chlorine-based gas. The atmosphere in the furnace at the time of the dehydration treatment and the transparency treatment is He 10
Liter / minute, Cl 2 200 cc / minute. This base material
The Cl content of the (core rod) was 0.3% by weight. Next, after stretching this base material (core rod) to a diameter of 5 mm,
Around this, 14 fine particles of SiO 2 glass were
Deposited 0 mm thick. The obtained base material (core rod and
(Composite of lath particulates) was inserted into a furnace maintained at 1350 ° C., and He 10 L / min, SiF 4 300
After supplying cc / min and adding fluorine, the furnace temperature was raised to 1550 ° C. in the same atmosphere to form a vitrified transparent glass. The thus obtained base material having a core-clad (preform
Was made into a fiber having an outer diameter of 125 μm, and the characteristics were examined.
【0009】比較例1 実施例1と同様の方法にて、塩素系ガスとしてCCl4
を用い、純粋石英ガラスロッド(コアロッド)を作成し
た。脱水処理、透明化の際の炉内雰囲気は、He 10リ
ットル/分、CCl4 20cc/分、O2 60cc/分
である。この母材(コアロッド)のCl量は0.05重
量%であった。次にこの母材(コアロッド)を直径5m
mに延伸したのち、その周りに外付け法によりSiO2
ガラス微粒子を140mm厚に堆積させた。得られた母
材(コアロッドとガラス微粒子堆積体の複合体)を13
50℃に維持された炉内に挿入し、He 10リットル/
分、SiF4 300cc/分を供給して、フッ素添加し
た後、同雰囲気にて炉温を1550℃に昇温して透明ガ
ラス化した。こうして得られたコア−クラッドを有する
母材(プリフォーム)を外径125μmのファイバに
し、特性を調べた。Comparative Example 1 In the same manner as in Example 1, CCl 4 was used as a chlorine-based gas.
Was used to produce a pure quartz glass rod (core rod) . The atmosphere in the furnace at the time of dehydration treatment and clarification is He 10 liter / min, CCl 4 20 cc / min, and O 2 60 cc / min. The Cl content of this base material (core rod) was 0.05% by weight. Next, this base material ( core rod ) is
m, and then SiO 2 is stretched around it by an external method.
Glass particles were deposited to a thickness of 140 mm. The obtained base material (composite of core rod and glass fine particle deposit) was added to 13
Inserted in a furnace maintained at 50 ° C., He 10 liters /
After supplying 300 cc / min of SiF 4 and adding fluorine, the furnace temperature was increased to 1550 ° C. in the same atmosphere to form a transparent glass. The base material (preform) having the core-cladding thus obtained was made into a fiber having an outer diameter of 125 μm, and the characteristics were examined.
【0010】実施例1,2と比較例1から作製されたフ
ァイバ特性の比較 以上のようにして得たCl量の異なる3本のファイバに
ついて、各々残留応力、比屈折率差、ファイバ構造(λ
c,MFD)を調べた結果を、図1〜図3に比較して示
す。図1から判るように、純粋石英ガラス中のCl量が
多いほど、線引後の残留応力が小さくなる。即ち、Cl
量が多い母材ほど石英ガラスの粘度が小さくなると推定
される。ファイバ内残留応力が少なくなった結果、図2
に示すように、コア−クラッドの比屈折率差は、Cl量
が多いほど高くなっていて、プリフォームでの測定値に
近い。図3はCl量の異なる各々のファイバのλc,M
FD測定結果を示したものである。図3から明らかなよ
うに、Cl量が多いファイバほど、比屈折率差はプリフ
ォームの段階での測定値に近いことから、λc,MFD
は予測値に近く、変動幅が小さい。Comparison of Fiber Characteristics Made from Examples 1 and 2 and Comparative Example 1 Regarding the three fibers having different Cl contents obtained as described above, the residual stress, the relative refractive index difference, and the fiber structure (λ
c, MFD) are shown in comparison with FIGS. As can be seen from FIG. 1, the greater the Cl content in the pure quartz glass, the smaller the residual stress after drawing. That is, Cl
It is estimated that the viscosity of the quartz glass decreases as the amount of the base material increases. As a result of reducing the residual stress in the fiber, FIG.
As shown in the figure, the relative refractive index difference between the core and the clad increases as the Cl content increases, and is close to the measured value of the preform. FIG. 3 shows λc, M of each fiber having a different Cl amount.
9 shows FD measurement results. As is clear from FIG. 3, since the relative refractive index difference is closer to the measured value at the preform stage for a fiber having a larger Cl content, λc, MFD
Is close to the predicted value and the fluctuation range is small.
【0011】[0011]
【発明の効果】以上示したように、本発明によれば純粋
石英ガラス中のハロゲン量、特にはCl量を多くするこ
とにより純石英コア−フッ素添加石英クラッドシングル
モードファイバのコア部の粘性をさげることができ、そ
の結果、線引時に生じる残留応力を低減することができ
る。従って、線引後のコア−クラッド比屈折率差はプリ
フォーム段階での実測値とほぼ一致し、λc,MFD特
性も予測値とほぼ一致させることが可能となり、極めて
効果的である。As described above, according to the present invention, the viscosity of the core portion of a pure quartz core -fluorine-doped quartz clad single mode fiber can be reduced by increasing the amount of halogen, particularly Cl, in pure quartz glass. As a result, the residual stress generated at the time of drawing can be reduced. Therefore, the core-clad relative refractive index difference after drawing almost matches the actual measurement value at the preform stage, and the λc and MFD characteristics can almost match the predicted values, which is extremely effective.
【図1】純粋石英ガラス化中のCl量と、ファイバの残
留応力との関係を示す図である。FIG. 1 is a graph showing the relationship between the amount of Cl during vitrification of pure silica and the residual stress of a fiber.
【図2】純粋石英ガラス化中のCl量と、ファイバのコ
ア−クラッド間比屈折率差との関係を示す図である。FIG. 2 is a graph showing the relationship between the Cl content during vitrification of pure silica and the relative refractive index difference between a core and a clad of a fiber.
【図3】純粋石英ガラス化中のCl量と、ファイバのλ
c,MFDとの関係を示す図である。FIG. 3: Cl content during vitrification of pure silica and λ of fiber
It is a figure which shows the relationship with c, MFD.
【図4】純石英コア−フッ素添加石英クラッドファイバ
の屈折率分布を示す図である。FIG. 4 is a diagram showing a refractive index distribution of a pure quartz core-fluorine-doped quartz clad fiber.
【図5】ガラス微粒子体の作成方法を示す概略図であ
る。FIG. 5 is a schematic view showing a method for producing a glass particle body.
【図6】多孔質母材の焼結工程を示す概略図である。FIG. 6 is a schematic view showing a step of sintering a porous preform.
1 ガラス微粒子体(多孔質母材) 2 バーナ 3 出発部材 4 ヒータ 5 炉心管 DESCRIPTION OF SYMBOLS 1 Glass particulate body (porous base material) 2 Burner 3 Starting member 4 Heater 5 Core tube
───────────────────────────────────────────────────── フロントページの続き (58)調査した分野(Int.Cl.7,DB名) C03B 37/00 - 37/16 C03C 1/00 - 14/00 ──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. 7 , DB name) C03B 37/00-37/16 C03C 1/00-14/00
Claims (3)
理および透明ガラス化してガラス母材とした後に線引し
て光ファイバを得る方法において、該脱水処理工程およ
び/又は透明ガラス化工程においてハロゲン系ガスを含
む雰囲気中で加熱処理することにより石英ガラス中にハ
ロゲンを0.3〜1重量%含ませ、これにより得られた
ガラス母材を光ファイバのコアとして用い、且つフッ素
添加石英系ガラスをクラッドとして用いることを特徴と
する光ファイバの製造方法。1. A method for obtaining an optical fiber by dehydrating a transparent preform containing quartz as a main component and vitrifying the porous preform to obtain a glass preform, wherein the dehydrating step and / or the transparent vitrification are performed. In the process, halogen is added to quartz glass by heat treatment in an atmosphere containing a halogen-based gas. A method for producing an optical fiber, comprising 3 to 1% by weight, using the glass preform obtained as a core of the optical fiber, and using a fluorine-doped quartz glass as a clad.
する請求項1記載の光ファイバの製造方法。2. The method according to claim 1, wherein said halogen is chlorine.
を有してなり、かつ該コアは塩素を含むハロゲンを0.
3〜1重量%含ませた石英ガラスからなることを特徴と
する石英系光ファイバ。3. A core and a fluorine-doped quartz glass clad, wherein the core contains chlorine-containing halogen in an amount of 0.1 to 1 mm.
A quartz-based optical fiber comprising quartz glass containing 3 to 1% by weight.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP18458791A JP3106564B2 (en) | 1991-07-24 | 1991-07-24 | Manufacturing method of optical fiber and silica-based optical fiber |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP18458791A JP3106564B2 (en) | 1991-07-24 | 1991-07-24 | Manufacturing method of optical fiber and silica-based optical fiber |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH0524873A JPH0524873A (en) | 1993-02-02 |
JP3106564B2 true JP3106564B2 (en) | 2000-11-06 |
Family
ID=16155819
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP18458791A Expired - Lifetime JP3106564B2 (en) | 1991-07-24 | 1991-07-24 | Manufacturing method of optical fiber and silica-based optical fiber |
Country Status (1)
Country | Link |
---|---|
JP (1) | JP3106564B2 (en) |
Families Citing this family (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6334338B1 (en) | 1998-07-02 | 2002-01-01 | Lucent Technologies Inc. | Sol gel process of making a fiber preform with removal of oxide particles |
WO2000042458A1 (en) | 1999-01-18 | 2000-07-20 | Sumitomo Electric Industries, Ltd. | Optical fiber and method of manufacture thereof |
CN1285522C (en) * | 2001-06-13 | 2006-11-22 | 住友电气工业株式会社 | Glass precast rod and method for producing glass precast rod |
US8015878B2 (en) * | 2006-10-05 | 2011-09-13 | Delaware State University Foundation, Inc. | Fiber optics sound detector |
US9618692B2 (en) * | 2014-07-10 | 2017-04-11 | Corning Incorporated | High chlorine content low attenuation optical fiber |
US9594210B2 (en) | 2015-06-30 | 2017-03-14 | Corning Incorporated | Optical fiber with large effective area and low bending loss |
JP6951852B2 (en) | 2017-03-27 | 2021-10-20 | 古河電気工業株式会社 | Optical fiber and manufacturing method of optical fiber |
-
1991
- 1991-07-24 JP JP18458791A patent/JP3106564B2/en not_active Expired - Lifetime
Also Published As
Publication number | Publication date |
---|---|
JPH0524873A (en) | 1993-02-02 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
Schultz | Fabrication of optical waveguides by the outside vapor deposition process | |
JP2959877B2 (en) | Optical fiber manufacturing method | |
US4846867A (en) | Method for producing glass preform for optical fiber | |
GB1597041A (en) | Method of making optical waveguides | |
Blankenship et al. | The outside vapor deposition method of fabricating optical waveguide fibers | |
JPH11209141A (en) | Production of segment core optical waveguide preform | |
JP3106564B2 (en) | Manufacturing method of optical fiber and silica-based optical fiber | |
CA1266403A (en) | Method for producing glass preform for optical fiber containing fluorine in cladding | |
JPH05350B2 (en) | ||
JPH0380740B2 (en) | ||
JPH0416427B2 (en) | ||
JPH07230015A (en) | Dispersion shift type single-mode optical fiber, and preform for the same and its manufacture | |
DK167463B1 (en) | PROCEDURE FOR PREPARING A PRIOR STAGE TO AN OPTICAL FIBER | |
WO2001072648A1 (en) | Substrate tube and process for producing a preform for an optical fiber | |
US5641333A (en) | Increasing the retention of Ge02 during production of glass articles | |
JP2017024917A (en) | Optical fiber preform, optical fiber, and manufacturing method for optical fiber | |
JPH0820574B2 (en) | Dispersion shift fiber and manufacturing method thereof | |
JP3174682B2 (en) | Method for producing glass preform for optical fiber | |
JPS6313946B2 (en) | ||
JPH0798671B2 (en) | Method for manufacturing preform for optical fiber | |
AU698054B2 (en) | Increasing the retention of GeO2 during production of glass articles | |
JPH06219765A (en) | Production of preform for optical fiber | |
JP3439258B2 (en) | Method for producing glass preform for optical fiber | |
JPS61251539A (en) | Optical fiber | |
JPH02201403A (en) | Optical fiber and production of base material thereof as well as production of optical fiber |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
FPAY | Renewal fee payment (prs date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20070908 Year of fee payment: 7 |
|
FPAY | Renewal fee payment (prs date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20080908 Year of fee payment: 8 |
|
FPAY | Renewal fee payment (prs date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20090908 Year of fee payment: 9 |
|
FPAY | Renewal fee payment (prs date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20090908 Year of fee payment: 9 |
|
FPAY | Renewal fee payment (prs date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100908 Year of fee payment: 10 |
|
FPAY | Renewal fee payment (prs date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100908 Year of fee payment: 10 |
|
FPAY | Renewal fee payment (prs date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110908 Year of fee payment: 11 |
|
EXPY | Cancellation because of completion of term |