JPS6291439A - Production of fluorine-added transparent quartz glass body - Google Patents
Production of fluorine-added transparent quartz glass bodyInfo
- Publication number
- JPS6291439A JPS6291439A JP23098385A JP23098385A JPS6291439A JP S6291439 A JPS6291439 A JP S6291439A JP 23098385 A JP23098385 A JP 23098385A JP 23098385 A JP23098385 A JP 23098385A JP S6291439 A JPS6291439 A JP S6291439A
- Authority
- JP
- Japan
- Prior art keywords
- fluorine
- atmosphere
- stage
- heat treatment
- contg
- 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
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
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)
- Glass Melting And Manufacturing (AREA)
- Manufacture, Treatment Of Glass Fibers (AREA)
- Glass Compositions (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は弗素添加透明石英ガラス体の製造方法に関する
ものであって、本発明によシ得られる該ガラス体は高純
度で屈折率の低いガラスであるため、光フアイバ用ガラ
ス、特に光ファイバのクラッド部のガラスとして例えば
純５１０２をコアとしたファイバのクラッド部用ガラス
として、好適に用いることができる。[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for manufacturing a fluorine-doped transparent quartz glass body, and the glass body obtained by the present invention has high purity and a low refractive index. Since it is a glass, it can be suitably used as a glass for optical fibers, particularly as a glass for the cladding portion of an optical fiber, for example, as a glass for the cladding portion of a fiber having a pure 5102 core.
従来、弗素を添加した石英（ｓｔｏ２）ガラスを合成す
る方法として、■ＡＤ法等により得られる純シリカガラ
ス微粒子体（以下スート体と称する）を、通常８Ｆ６．
ＯＦ４ 等の気相弗化物を原料とする弗素雰囲気中
にて加熱処理する方法が知られている。これは、能率よ
く弗素添加５１０２ガラスを合成できる方法である。Conventionally, as a method for synthesizing fluorine-doped quartz (STO2) glass, pure silica glass fine particles (hereinafter referred to as soot bodies) obtained by the AD method etc. are usually 8F6.
A method of heat treatment in a fluorine atmosphere using a gas phase fluoride such as OF4 as a raw material is known. This is a method that can efficiently synthesize fluorine-doped 5102 glass.
しかし、上記した従来法には以下のような欠点があった
。However, the conventional method described above has the following drawbacks.
すなわち、弗素をガラス中に均一に、かつ高濃度に添加
しようとすると、石英ガラス等からなる炉心管が、弗化
物原料によるエツチング作用を強くうけて、劣化もしく
は消耗が著るしいという問題があったことである。In other words, if fluorine is added uniformly and at a high concentration into glass, there is a problem in that the reactor core tube made of quartz glass or the like is strongly etched by the fluoride raw material, resulting in significant deterioration or wear. That's what happened.
例えば温度１４００℃以上の高温の弗素雰囲気でスート
体を加熱処理して弗素を添加しようとすると、ガラスロ
ッドの外周部により多く弗素が添加され、このため得ら
れたガラス体の径方向の屈折率分布は第２図のような分
布になり易い。For example, if an attempt is made to add fluorine by heat-treating the soot body in a fluorine atmosphere at a high temperature of 1400°C or higher, more fluorine will be added to the outer periphery of the glass rod, resulting in a radial refractive index of the resulting glass body. The distribution tends to be as shown in Figure 2.
一方、例えば温度１２００℃程度の低温において弗素を
添加し、次にこれに透明ガラス化のための熱処理を行う
と、ガラスロッドの外周部より弗素の揮散が生じ、この
ために得られたガラス体の屈折率分布としては第６図の
ような分布となシ易い。On the other hand, when fluorine is added at a low temperature of about 1200°C and then heat treated to make it transparent, fluorine volatilizes from the outer periphery of the glass rod, resulting in the glass body being obtained. The refractive index distribution is likely to be as shown in FIG.
そして、スート体を低温から高温まで昇温しながら弗素
雰囲気にて加熱処理をするときには、第１図のような径
方向に均一な屈折率分布のガラス体を得ることができる
。しかるに、この場合には弗素雰囲気下における加熱が
高温で長時間行なわれるため、上記した炉心管の劣化が
非常に激しくなってしまうのである。When the soot body is heated in a fluorine atmosphere while being heated from a low temperature to a high temperature, a glass body having a uniform refractive index distribution in the radial direction as shown in FIG. 1 can be obtained. However, in this case, heating in a fluorine atmosphere is carried out at high temperatures for a long period of time, resulting in extremely severe deterioration of the above-mentioned furnace core tube.
本発明は上記した問題点を解決し、弗素添加濃度が径方
向で均一なガラス体を、炉心管劣化の少ない状態で得る
という新規な弗素添加透明石英ガラス体の製造方法を提
供せんとするものである。The present invention solves the above-mentioned problems and provides a novel method for producing a fluorine-doped transparent quartz glass body, in which a glass body having a uniform fluorine doping concentration in the radial direction can be obtained with little deterioration of the furnace tube. It is.
本発明はシリカガラス微粒子体を弗化物雰囲気で加熱処
理して弗素添加透明石英ガラス体を得る方法において、
該シリカガラス微粒子体を１２００℃以上１４００℃の
温度でＨθを含み弗化物を含壕ない雰囲気にて第１段加
熱処理を行い、次に該第１段加熱処理よりも低い温度で
弗化物を含む雰囲気にて第２段加熱処理を行ない、この
後さらに上記第１段加熱処理よりも高い温度で少なくと
もＨθ を含む雰囲気にて第６段加熱処理を行って透明
ガラス化する、ことを特徴とする弗素添加透明石英ガラ
ス体の製造方法である。The present invention provides a method for obtaining a fluorine-doped transparent quartz glass body by heat-treating a silica glass fine particle body in a fluoride atmosphere.
The silica glass fine particles are subjected to a first heat treatment at a temperature of 1200° C. or more to 1400° C. in an atmosphere containing Hθ and not containing fluoride, and then subjected to a fluoride treatment at a temperature lower than the first heat treatment. A second stage heat treatment is performed in an atmosphere containing Hθ, and then a sixth stage heat treatment is performed in an atmosphere containing at least Hθ at a higher temperature than the first stage heat treatment to obtain transparent vitrification. This is a method for producing a fluorine-doped transparent quartz glass body.
本発明の特に好ましい実施態様としては、シリカガラス
微粒子体がＶＡＤ法により形成されたものである上記方
法又は第１段加熱処理において雰囲気に塩素もしくは塩
化物ガスを添加して行う上記方法が挙げられる。Particularly preferred embodiments of the present invention include the above method in which the silica glass fine particles are formed by a VAD method, or the above method in which chlorine or chloride gas is added to the atmosphere in the first stage heat treatment. .
本発明者らは鋭意研究の結果、加熱処理の温度とその際
の雰囲気を調整することで、弗素濃度が第１図のように
径方向に均一なガラス体を、炉心管の劣化が少なく得ら
れることを見出した。As a result of intensive research, the inventors of the present invention have found that by adjusting the heat treatment temperature and atmosphere, it is possible to create a glass body with a uniform fluorine concentration in the radial direction as shown in Figure 1, with less deterioration of the furnace tube. I found out that it can be done.
以下図面を参照して本発明の詳細な説明する。The present invention will be described in detail below with reference to the drawings.
第４図はＶＡＤ法によりスート体を合成する方法の説明
図であって、バーナ１にはＨ２＋ ０２ ＋Ａｒ等のシ
ールガス、及びＳ ｉ Ｃｔ４等の原料ガスが供給され
、フレーム２の中で形成された０、 １μｍ以下の５ｉ
０２ ガラス微粒子（スート）は、回転しつつ徐々に引
き上げられる回転棒３の先端に堆積して、スート体４が
形成される。スート体４のカサ密度は通常０．２〜０．
４ ：／／ｃ−程度である。所定の大きさのスート体が
得られた後、このスート体を、ヒート長の長い均熱炉（
第５図に概略の構成を示す）、或いはヒート長が短かく
上下移動が必要なゾーン炉（第６図に概略の構成を示す
）に挿入し、熱処理を行う。本発明の方法は均熱炉、ゾ
ーン炉のどちらの炉についても適用し得るものである。FIG. 4 is an explanatory diagram of a method for synthesizing a soot body by the VAD method, in which a seal gas such as H2+02+Ar and a raw material gas such as S i Ct4 are supplied to the burner 1, and soot is formed in the frame 2. 5i of less than 0 or 1 μm
02 Glass fine particles (soot) are deposited on the tip of the rotating rod 3 which is gradually pulled up while rotating, and the soot body 4 is formed. The bulk density of the soot body 4 is usually 0.2 to 0.
4: //c- level. After obtaining a soot body of a predetermined size, this soot body is placed in a soaking furnace with a long heat length (
5), or a zone furnace with a short heat length that requires vertical movement (the schematic configuration is shown in FIG. 6) for heat treatment. The method of the present invention can be applied to both soaking furnaces and zone furnaces.
１
以下、主に均熱炉を例に説明する。第５図において５は
ヒータであジ、スートの全長がとのヒータ５によ勺、は
ぼ均一に加熱される。６は炉心管であり、７は雰囲気ガ
スの導入管である。1 The explanation will be given below mainly using a soaking furnace as an example. In FIG. 5, reference numeral 5 denotes a heater, and the entire length of the soot is heated almost uniformly by the heater 5. 6 is a furnace core tube, and 7 is an atmospheric gas introduction tube.
炉心管６としては、高温加熱時に不純物揮散が少なく耐
熱性の高い石英ガラス製のものが好ましい。The furnace core tube 6 is preferably made of quartz glass, which has high heat resistance and less volatilization of impurities during high-temperature heating.
本発明においては、第１段加熱処理として、１２００〜
１４００℃の温度範囲で加熱する。In the present invention, as the first stage heat treatment, 1200~
Heat in the temperature range of 1400°C.
この際の雰囲気はＨｅ を流しながら行うと、最終製品
にアワの残留がなく好ましい。また、弗化物ガスの存在
は、ガラスの粘性低下による急檄な焼結を生じるため、
好ましくない。またこの第１段加熱処理において、脱水
を充分に行う目的で、雰囲気ガスに塩素もしくは塩化物
を添加することができる。加熱時間としては、スートの
サイズにもよるが、１時間程度が適している。この第１
段加熱処理によシ、カサ密度がスート体の径方向で比較
的一様な半焼結体が得られる。加熱温度が１４００℃以
上になると、焼結が大きく生じるために、次の段階にて
行う弗素の添加効率が下がる。また、１２００℃以下で
は、弗素を均一に導入するという効果が薄れる。このよ
うな第１段加熱処理工程の導入によシ、透明ガラス化処
理時の弗素の揮散がほぼ完全におさえられることが判明
した。It is preferable to carry out the process while flowing He 2 in the atmosphere so that no bubbles remain in the final product. In addition, the presence of fluoride gas causes rapid sintering due to a decrease in the viscosity of the glass.
Undesirable. In addition, in this first stage heat treatment, chlorine or chloride can be added to the atmospheric gas for the purpose of sufficient dehydration. The suitable heating time is about 1 hour, although it depends on the size of the soot. This first
By performing the step heat treatment, a semi-sintered body having a relatively uniform bulk density in the radial direction of the soot body can be obtained. If the heating temperature exceeds 1400° C., sintering will occur to a large extent, which will reduce the efficiency of adding fluorine in the next step. Further, below 1200° C., the effect of uniformly introducing fluorine is weakened. It has been found that by introducing such a first heat treatment step, volatilization of fluorine during transparent vitrification treatment can be almost completely suppressed.
以上の第１段加熱処理が終った後、ヒータ温度を該第１
段加熱温度よシ低温にて、第２段加熱処理を行う。この
とき雰囲気に例えばＳＦ６゜ＣＦ４ 、 Ｃ０４２Ｆ２
、 ＳｉＦ４ 等の弗化物ガスの導入することによ
りガラスへの弗素添加を行うが、Ｈｅと弗化物ガス量の
比率を変えることにより、ガラス中の弗素濃度を変える
ことができる。加熱温度を上げることによっても、ガラ
ス中の弗素濃度を上げ得る場合もあるが、炉心管の劣化
あるいは不純物の混入が増加するので好ましく々い。通
常この第２段加熱処理は温度１２００℃以下かで時間は
２時間程度好ましい。After the first stage heat treatment is completed, the heater temperature is adjusted to the first stage.
The second stage heat treatment is performed at a lower temperature than the stage heating temperature. At this time, the atmosphere contains, for example, SF6°CF4, C042F2.
Although fluorine is added to the glass by introducing a fluoride gas such as , SiF4, etc., the fluorine concentration in the glass can be changed by changing the ratio of He to fluoride gas. In some cases, the fluorine concentration in the glass can be increased by increasing the heating temperature, but this is not preferred since it increases the deterioration of the furnace tube or the contamination of impurities. Usually, this second stage heat treatment is preferably performed at a temperature of 1200° C. or lower and for a time of about 2 hours.
第２段加熱処理の終了後、ヒータ温度を第１段加熱処理
の温度より更に高く上げ、第３段加熱処理を行ない、半
焼結体を完全透明ガラス化する。このときの加熱温度は
、ガラス中の弗素添加量に依存するが、約１４５０℃〜
１６００℃である。このときの雰囲気はＨｅ １００％
雰囲気が好ましい。この段階での弗化物の添加は、炉心
管の寿命を極めて短かくするので、好ましくない。After the second-stage heat treatment is completed, the heater temperature is raised higher than the temperature of the first-stage heat treatment, and a third-stage heat treatment is performed to completely transform the semi-sintered body into transparent glass. The heating temperature at this time depends on the amount of fluorine added in the glass, but is approximately 1450°C ~
The temperature is 1600°C. The atmosphere at this time was 100% He.
The atmosphere is favorable. Addition of fluoride at this stage is undesirable because it extremely shortens the life of the furnace tube.
実施例１
第４図の構成によｊＤＶＡＤ法にて作製した、外径１０
０ｍｍ）長さ５００ ｍｍの純５ｉｎ２のスート体を、
第５図のような均熱炉にセットし、表１の条件にて加熱
処理したところ、その屈折率分布が第１図グラフのよう
に径方向に一様であシ、その屈折率値が純石英に比べて
０．３チ低い透明ガラス体が得られた。Example 1 An outer diameter of 10 was produced by the jDVAD method with the configuration shown in Fig. 4.
0mm) A pure 5in2 soot body with a length of 500mm,
When it was placed in a soaking furnace as shown in Figure 5 and heat treated under the conditions shown in Table 1, the refractive index distribution was uniform in the radial direction as shown in the graph in Figure 1, and the refractive index value was A transparent glass body 0.3 inches lower than pure quartz was obtained.
同一条件にて、同一母材（透明ガラス体）をくシ返し作
製したところ、肉厚ｓｍｍの石英ガラス製炉心管は３０
本以上の母材作製まで使用することができ、従来法に比
し、大巾に炉心管寿命が延びた。When the same base material (transparent glass body) was fabricated under the same conditions, the quartz glass furnace core tube with a wall thickness of smm was 30 mm.
It can be used to produce base metals larger than 100 mm, and the life of the furnace tube has been greatly extended compared to conventional methods.
表 １
実施例２
第１段加熱処理においてａｔ２＠ ｏ、 〃分 添加し
た以外はすべて実施例１と同様に行って、透明ガラス体
を作製した。得られたガラス体について、赤外分光光度
計によシ残留水分の分析を行ったところ、検知限界（０
，１ｐｐｍ ）以下のレベルであった。なお、実施例１
で得られたガラスにはｃＬ２〜［１３ｐｐｍのＯＨ量が
検知された。Table 1 Example 2 A transparent glass body was produced in the same manner as in Example 1 except that at2@o, 〃min was added in the first stage heat treatment. When the obtained glass body was analyzed for residual moisture using an infrared spectrophotometer, the detection limit (0
, 1 ppm) or less. In addition, Example 1
An OH amount of cL2 to 13 ppm was detected in the glass obtained.
比較例１〜３
実施例１と同様なスート体を表２の条件にて加熱処理し
た。その結果を表２に示す。Comparative Examples 1 to 3 Soot bodies similar to those in Example 1 were heat-treated under the conditions shown in Table 2. The results are shown in Table 2.
以上は均熱炉の場合を例にしたが、第６図のようなゾー
ン炉を用いても同様に効果を挙げうる。なお、第６図に
おいて４はスート体、５はヒータ、６は炉心管を示す。The above example uses a soaking furnace, but the same effect can be obtained by using a zone furnace as shown in FIG. In addition, in FIG. 6, 4 indicates a soot body, 5 a heater, and 6 a furnace core tube.
本発明の方法は、弗素添加量がガラスの径方向において
ほぼ均一な透明石英ガラスを、炉心管の劣化をひき起こ
さずに製造できるので、安定した品質のものを製造コス
トを安く得ることができる。The method of the present invention makes it possible to produce transparent quartz glass in which the amount of fluorine added is almost uniform in the radial direction of the glass without causing deterioration of the furnace tube, making it possible to obtain products of stable quality at low production costs. .
第１図ないし第５図はガラスの径方向における屈折率分
布を示すグラフであって、第１図は本発明の目的とする
一様な屈折率分布を示し、第２図及び第３図は一様でな
い屈折率分布の例を示す。
第４図はＶＡＤ法によシスート体を製造する方法の概略
説明図、
第５図は均熱炉を用いて加熱処理を行う方法の説明図、
第６図はゾーン炉を用いる場合の説明図である。1 to 5 are graphs showing the refractive index distribution in the radial direction of glass, in which FIG. 1 shows a uniform refractive index distribution which is the object of the present invention, and FIGS. An example of a non-uniform refractive index distribution is shown. Figure 4 is a schematic explanatory diagram of a method for producing a cysuto body by the VAD method, Figure 5 is an explanatory diagram of a method of heat treatment using a soaking furnace, and Figure 6 is an explanatory diagram of a method in which a zone furnace is used. It is.
Claims (3)
して弗素添加透明石英ガラス体を得る方法において、該
シリカガラス微粒子体を １２００℃以上１４００℃の温度でＨｅを含み弗化物を
含まない雰囲気にて第１段加熱処理を行い、次に該第１
段加熱処理よりも低い温度で弗化物を含む雰囲気にて第
２段加熱処理を行ない、この後さらに上記第１段加熱処
理よりも高い温度で少なくともＨｅを含む雰囲気にて第
３段加熱処理を行つて透明ガラス化する、ことを特徴と
する弗素添加透明石英ガラス体の製造方法。(1) In a method for obtaining a fluorine-doped transparent quartz glass body by heat-treating a silica glass fine particle body in a fluoride atmosphere, the silica glass fine particle body is heated at a temperature of 1200°C or more to 1400°C in an atmosphere containing He and not containing fluoride. The first stage heat treatment is performed at
A second stage heat treatment is performed in an atmosphere containing fluoride at a temperature lower than that of the stage heat treatment, and then a third stage heat treatment is performed in an atmosphere containing at least He at a temperature higher than the first stage heat treatment. 1. A method for manufacturing a fluorine-doped transparent quartz glass body, the method comprising the steps of:
化物ガスを添加して行う特許請求の範囲第（１）項に記
載される弗素添加透明石英ガラスの製造方法。(2) A method for producing fluorine-doped transparent quartz glass according to claim (1), which is performed by adding chlorine or chloride gas to the atmosphere in the first stage heat treatment.
たものである特許請求の範囲第（１）項に記載される弗
素添加透明石英ガラス体の製造方法。(3) A method for producing a fluorine-doped transparent quartz glass body according to claim (1), wherein the silica glass fine particles are formed by a VAD method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60230983A JPH0653590B2 (en) | 1985-10-18 | 1985-10-18 | Method for producing fluorine-containing transparent quartz glass body |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60230983A JPH0653590B2 (en) | 1985-10-18 | 1985-10-18 | Method for producing fluorine-containing transparent quartz glass body |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6291439A true JPS6291439A (en) | 1987-04-25 |
| JPH0653590B2 JPH0653590B2 (en) | 1994-07-20 |
Family
ID=16916388
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP60230983A Expired - Lifetime JPH0653590B2 (en) | 1985-10-18 | 1985-10-18 | Method for producing fluorine-containing transparent quartz glass body |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0653590B2 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS62182126A (en) * | 1986-02-04 | 1987-08-10 | Sumitomo Electric Ind Ltd | Production of glass preform for optical fiber |
| JPH02145448A (en) * | 1988-11-25 | 1990-06-04 | Furukawa Electric Co Ltd:The | Production of preform of optical fiber |
| EP1221430A2 (en) * | 2001-01-05 | 2002-07-10 | Lucent Technologies Inc. | Process of manufacturing fluorine-doped preforms for optical fibres |
| 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 |
|---|---|---|---|---|
| JPS6090843A (en) * | 1983-10-20 | 1985-05-22 | Sumitomo Electric Ind Ltd | Manufacture of glass base material for optical fiber |
-
1985
- 1985-10-18 JP JP60230983A patent/JPH0653590B2/en not_active Expired - Lifetime
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6090843A (en) * | 1983-10-20 | 1985-05-22 | Sumitomo Electric Ind Ltd | Manufacture of glass base material for optical fiber |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS62182126A (en) * | 1986-02-04 | 1987-08-10 | Sumitomo Electric Ind Ltd | Production of glass preform for optical fiber |
| JPH0791079B2 (en) * | 1986-02-04 | 1995-10-04 | 住友電気工業株式会社 | Method for manufacturing glass base material for optical fiber |
| JPH02145448A (en) * | 1988-11-25 | 1990-06-04 | Furukawa Electric Co Ltd:The | Production of preform of optical fiber |
| EP1221430A2 (en) * | 2001-01-05 | 2002-07-10 | Lucent Technologies Inc. | Process of manufacturing fluorine-doped preforms for optical fibres |
| EP1221430A3 (en) * | 2001-01-05 | 2003-01-08 | Lucent Technologies Inc. | Process of manufacturing fluorine-doped preforms for optical fibres |
| 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 |
|---|---|
| JPH0653590B2 (en) | 1994-07-20 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JPH0372583B2 (en) | ||
| JPS60260434A (en) | Manufacture of anhydrous glass preform for optical transmission | |
| JPS61247633A (en) | Production of glass base material for optical fiber | |
| JPS5844619B2 (en) | Manufacturing method of optical fiber base material | |
| JPS6291439A (en) | Production of fluorine-added transparent quartz glass body | |
| DK163658B (en) | PROCEDURE FOR MANUFACTURING A GLASS FRAME FOR OPTICAL FIBERS | |
| JPH08183621A (en) | Production of high-purity highly heat resistant silica glass | |
| JP3274955B2 (en) | Method for producing synthetic quartz glass base material for optical components for use in ultraviolet region, and method for producing synthetic quartz glass material | |
| JPH0952722A (en) | Optical synthetic quartz glass preform, its production and synthetic quartz glass product using the same | |
| JP2000026125A (en) | Transparent quartz glass and its production | |
| JPS62108744A (en) | Transparent vitrification method of porous glass base material | |
| JPH02217329A (en) | Production of glass preform for optical glass fiber | |
| JPS63190734A (en) | Production of optical fiber base material | |
| JPS6283323A (en) | Production of glass | |
| JP4230073B2 (en) | Method for producing aluminum-added glass base material | |
| JP2002249342A (en) | Glass body and method for manufacturing it | |
| JPH0416412B2 (en) | ||
| JPH03115136A (en) | Optical fiber preform and its production | |
| JPS63176325A (en) | Production of glass preform for optical fiber | |
| JP2022049501A (en) | Method for manufacturing optical fiber glass preform | |
| JPS61168544A (en) | Production of glass tube mainly composed of quartz | |
| JPH04325433A (en) | Production of optical fiber preform | |
| JP2003300736A (en) | Method for manufacturing glass preform | |
| JPH0226848A (en) | Production of high-purity quartz glass | |
| JPS62143834A (en) | Production of preform for optical fiber |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EXPY | Cancellation because of completion of term |