JP2612941B2 - Method for producing porous optical fiber preform - Google Patents
Method for producing porous optical fiber preformInfo
- Publication number
- JP2612941B2 JP2612941B2 JP1247225A JP24722589A JP2612941B2 JP 2612941 B2 JP2612941 B2 JP 2612941B2 JP 1247225 A JP1247225 A JP 1247225A JP 24722589 A JP24722589 A JP 24722589A JP 2612941 B2 JP2612941 B2 JP 2612941B2
- Authority
- JP
- Japan
- Prior art keywords
- burner
- optical fiber
- burners
- diameter
- carrier
- 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
- C03B2207/00—Glass deposition burners
- C03B2207/42—Assembly details; Material or dimensions of burner; Manifolds or supports
-
- 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
- C03B2207/52—Linear array of like burners
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B2207/00—Glass deposition burners
- C03B2207/60—Relationship between burner and deposit, e.g. position
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B2207/00—Glass deposition burners
- C03B2207/60—Relationship between burner and deposit, e.g. position
- C03B2207/66—Relative motion
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B2207/00—Glass deposition burners
- C03B2207/70—Control measures
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Manufacture, Treatment Of Glass Fibers (AREA)
Description
【発明の詳細な説明】 （産業上の利用分野） 本発明は光ファイバ多孔質母材、特にはけい素化合物
を複数の酸水素火炎バーナーで加水分解して得たガラス
微粒子を担体上に堆積させる外付けCVD法により、大型
の光ファイバ多孔質母材を生産性よく製造する方法に関
するものである。DETAILED DESCRIPTION OF THE INVENTION (Industrial application field) The present invention deposits, on a carrier, glass microparticles obtained by hydrolyzing an optical fiber porous preform, particularly a silicon compound, with a plurality of oxyhydrogen flame burners. The present invention relates to a method for manufacturing a large-sized optical fiber porous preform with high productivity by an external CVD method.
（従来の技術） 光ファイバ母材は、けい素化合物を酸水素火炎バーナ
ーで加水分解して得たガラス微粒子を耐熱性の担体上に
堆積するという外付けCVD法によって多孔質母材を作
り、これを焼結し、透明ガラス化することによって作ら
れているが、この多孔質母材の大型化およびその生産性
向上のためにはこのバーナーを複数個使用する方法が汎
用されている。(Prior art) An optical fiber preform is made of a porous preform by an external CVD method in which glass particles obtained by hydrolyzing a silicon compound with an oxyhydrogen flame burner are deposited on a heat-resistant carrier. It is produced by sintering the glass to form a transparent glass. In order to increase the size of the porous base material and improve its productivity, a method using a plurality of burners is widely used.
（発明が解決しようとする課題） しかし、この外付けCVD法による多孔質母材の製造に
おいて複数のバーナーを用いる場合、通常このバーナー
は一定間隔で設置されており、この間隔が小さくて２つ
のバーナーが近づきすぎると火炎同志が干渉し合うため
にガラス微粒子の堆積効率が低下し、またこの間隔が大
きくてバーナー間隔が開きすぎるとガラス微粒子堆積部
の両端テーパー部が大きくなって有効部が短かくなり、
歩留りがわるくなるという不利がある。(Problems to be Solved by the Invention) However, when a plurality of burners are used in the production of the porous base material by the external CVD method, the burners are usually installed at regular intervals. If the burners are too close, the flames interfere with each other and the deposition efficiency of the glass particles decreases, and if this interval is too large and the burner interval is too wide, the taper at both ends of the glass particle deposition area becomes large and the effective area becomes short. It becomes
There is a disadvantage that the yield becomes poor.
（課題を解決するための手段） 本発明はこのような不利を解決することのできる光フ
ァイバ多孔質母材の製造方法に関するものであり、これ
は複数のバーナーを用いて外付けCVD法により担体上に
ガラス微粒子を堆積させた光ファイバ多孔質母材を製造
する方法において、該バーナーの間隔をガラス微粒子を
堆積の有効堆積部にではバーナー径の４倍以上とし、テ
ーパー部においてはバーナー径の３倍以下とすることを
特徴とするものである。(Means for Solving the Problems) The present invention relates to a method for producing an optical fiber porous preform that can solve such disadvantages, and this method uses a plurality of burners and a carrier by an external CVD method. In a method of manufacturing an optical fiber porous preform having glass fine particles deposited thereon, the interval between the burners is set to four times or more the burner diameter in an effective deposition portion for depositing the glass fine particles, and the burner diameter is reduced in a tapered portion. It is characterized by being three times or less.
すなわち、本発明者らは酸水素火炎バーナーを複数本
使用する外付けCVD法によって光ファイバ多孔質母材を
製造する方法において、これを効率よく実施する方法に
ついて種々検討した結果、第２図に示すようにここに使
用する複数個のバーナーの間隔を固定化せずにこれを可
動とし、有効堆積部においてはのバーナー間隔をバーナ
ー径の４倍以上とすると各バーナーの火炎同志が干渉し
合うことがなくなるので、この部分でのガラス微粒子の
堆積効率を85％以上とすることができること、また第３
図に示すようにテーパー部についてはこのバーナー間隔
をバーナー径の３倍以下とするとこのテーパー部をほぼ
一定で最小値とすることができることを見出し、その結
果有効堆積部を最長とすることができるということを確
認して本発明を完成させた。That is, the present inventors have conducted various studies on a method for efficiently performing the optical fiber porous preform by the external CVD method using a plurality of oxyhydrogen flame burners, and as a result, FIG. As shown in the figure, if the interval between the plurality of burners used here is not fixed, but is made movable, and the interval between the burners in the effective deposition portion is set to four times or more the burner diameter, the flames of the respective burners interfere with each other. Therefore, the deposition efficiency of the glass particles in this portion can be made 85% or more.
As shown in the figure, it has been found that, when the burner interval is set to three times or less of the burner diameter, the taper portion can be made almost constant and the minimum value. As a result, the effective deposition portion can be made the longest. After confirming that, the present invention was completed.
以下これをさらに詳述する。 This will be described in more detail below.
（作用） 本発明による光ファイバ多孔質母材の製造は外付けCV
D法で行なわれる。(Operation) The production of the optical fiber porous preform according to the present invention is performed by using an external CV.
Performed by the D method.
これは四塩化けい素（SiCl4）などのけい素化合物を
酸水素火炎バーナーに送り、この酸水素火炎で加水分解
してガラス微粒子を生成させ、これを合成石英、炭化け
い素、炭素などの耐熱性材料からなる担体上に堆積して
多孔質ガラスを母材とするのであるが、この担体上への
ガラス微粒子の堆積を増加させるために本発明の方法で
はこの酸水素火炎バーナーが２個または２個以上の複数
個で行なわれる。This sends a silicon compound such as silicon tetrachloride (SiCl 4 ) to an oxyhydrogen flame burner, which hydrolyzes it into fine glass particles, which is then converted to synthetic quartz, silicon carbide, carbon, etc. The porous glass is used as a base material deposited on a carrier made of a heat-resistant material. In order to increase the deposition of glass particles on the carrier, the method of the present invention uses two oxyhydrogen flame burners. Alternatively, it is performed by two or more pieces.
つぎにこれを添付の図面にともづいて説明する。第１
図は本発明の方法による光ファイバ多孔質母材の製造装
置の縦断面図を示したものであり、光ファイバ多孔質母
材１は合成石英、炭化けい素、炭素などのような耐熱性
の担体２の上に、四塩化けい素などのガス状けい素化合
物を送入している酸水素火炎バーナー３−1,3−２・・
・などでけい素化合物を加水分解して得たガラス微粒子
４を堆積させることによって作られるが、このバーナー
３−1,3−２はバーナー台５にバーナー間隔が調整でき
るように載置されており、このものは多孔質母材の直径
を略々均一にするということから担体２またはこのバー
ナー台５のいずれかまたは両者が左右に一定の速度で移
動できるようにされている。Next, this will be described with reference to the accompanying drawings. First
The figure shows a longitudinal sectional view of an apparatus for manufacturing a porous optical fiber preform according to the method of the present invention. The porous optical fiber preform 1 is made of a heat-resistant material such as synthetic quartz, silicon carbide, carbon or the like. An oxyhydrogen flame burner 3-1, 3-2,... Which feeds a gaseous silicon compound such as silicon tetrachloride onto a carrier 2.
The burners 3-1 and 3-2 are formed by depositing glass fine particles 4 obtained by hydrolyzing a silicon compound by, for example, such that the burner interval can be adjusted. Since the diameter of the porous base material is made substantially uniform, one or both of the carrier 2 and the burner base 5 can be moved right and left at a constant speed.
このようにして作られた多孔質母材は図に示されてい
るように径が略々均一とされている直胴部（以下これを
有効堆積部と略記する）と三角形状の端末部（以下これ
をテーパー部と略記する）とによって構成されている
が、本発明の方法ではこの多孔質母材１を大型のものと
すること、またこの生産性を向上させるために酸水素火
炎バーナー３が複数個使用されている。As shown in the figure, the porous base material thus produced has a straight body (hereinafter referred to as an effective deposition part) having a substantially uniform diameter and a triangular end ( In the method of the present invention, the porous base material 1 is made large and the oxyhydrogen flame burner 3 is used in order to improve the productivity. Are used more than once.
しかして、この酸水素火炎バーナーは有効堆積部を形
成させるために少なくとも２本（３−１、３−２）が使
用されるが、この２本の酸水素火炎バーナー３−１、３
−２のバーナー間隔はバーナー径の４倍以上とする必要
がある。これはバーナー間隔がバーナー径の４倍以下で
あるとバーナー火炎同志が干渉し合ってガラス微粒子４
の担体２への堆積収率が低下してしまうが、これをバー
ナー径の４倍以上とすればバーナー火炎同志が干渉し合
うことがなくなるので、ガラス微粒子の有効堆積部への
堆積収率を85％以上とすることができる。Thus, at least two (3-1, 3-2) oxyhydrogen flame burners are used in order to form an effective deposition portion, and the two oxyhydrogen flame burners 3-1 and 3-2 are used.
The burner interval of -2 must be at least four times the burner diameter. If the burner interval is less than 4 times the burner diameter, the burner flames will interfere with each other and cause
The deposition yield of the fine particles on the carrier 2 is reduced, but if this is set to four times or more the burner diameter, the burner flames will not interfere with each other. It can be 85% or more.
また、このテーパ部におけるガラス微粒子の堆積はこ
のテーパー部が最終的には有効堆積部から切り離されて
回収されるもので光ファイバとされるものではなく、し
たがってできるだけ小さいものとすることがよいので、
酸水素火炎バーナー３−１、３−２が担体２の両末端に
移動してきたときにはこのバーナー間隔をバーナー径の
３倍以下と小さくすることが必要であり、これによれば
この部位ではバーナー火炎同志が干渉し合うのでガラス
微粒子４の担体２への堆積収率がわるくなるが、テーパ
ー部を最小とすることができる。In addition, the deposition of the glass particles in the tapered portion is preferably such that the tapered portion is finally separated from the effective deposition portion and collected, and is not used as an optical fiber. ,
When the oxyhydrogen flame burners 3-1 and 3-2 have moved to both ends of the carrier 2, it is necessary to reduce the burner interval to three times or less the burner diameter. Since the particles interfere with each other, the deposition yield of the glass fine particles 4 on the carrier 2 becomes poor, but the tapered portion can be minimized.
すなわち、本発明による光ファイバ多孔質母材の製造
は、前記したように複数のバーナーを用いて外付けCVD
法で光ファイバ多孔質母材の製造する方法において、該
バーナーの間隔を有効堆積部ではバーナー径の４倍以上
とし、テーパー部ではバーナー径の３倍以下とするもの
であるが、これによれば最長の有効堆積部を得ることが
でき、ここでのガラス微粒子の堆積収率を85％以上とす
ることができるので大口径の光ファイバ多孔質母材を生
産性よく製造することができるし、テーパー部は少さく
することができるのでこの面からも生産性を向上させる
ことができるという有利性が与えられる。That is, the production of the optical fiber porous preform according to the present invention is performed by using an external CVD method using a plurality of burners as described above.
In the method of producing a porous optical fiber preform by the method, the interval between the burners is set to be four times or more the burner diameter in the effective deposition portion, and to three times or less the burner diameter in the tapered portion. In this case, the longest effective deposited portion can be obtained, and the deposition yield of the glass particles can be 85% or more, so that a large-diameter optical fiber porous preform can be manufactured with high productivity. In addition, since the number of tapered portions can be reduced, the advantage that productivity can be improved from this aspect is also provided.
（実施例） つぎに本発明の実施例をあげる。(Example) Next, an example of the present invention will be described.
実施例 担体軸方向に平行に左右に往復運動できるように口径
25mmの可動性酸水素バーナー２個を設置した第１図に示
した外付CVD法装置を使用し、これに担体として直径40m
mφ、長さ800mmのコア用石英ガラスロッドを設置し、40
rpmで回転させた。Example: Diameter so that it can reciprocate right and left in parallel with the carrier axis direction
The external CVD method shown in Fig. 1 equipped with two movable oxyhydrogen burners of 25 mm was used, and the diameter of the carrier was 40 m.
A quartz glass rod for core with mφ and length of 800 mm is installed, and 40
Rotated at rpm.
ついで装置中央に２本の酸水素火炎バーナーをバーナ
ー間隔がバーナー径の５倍である125mmとなすように設
置する（図中の（Ｂ））と共に、これらを担体と平行に
左右に100mm/分の速度で往復運動するようにし、このバ
ーナーに四塩化けい素（SiCl4）を300g/時、酸素ガスを
4m3/時、水素ガスを4m3/時で供給して着火し、この火炎
中でのSiCl4の加水分解で発生したシリカ微粒子を担体
上に堆積させ、このバーナーが担体の両端に近づいたと
き（図中の（Ａ）、（Ｃ））にはこの２本のバーナー間
隔をバーナー径の３倍以下である40mmになるようにし、
10時間ガラス微粒子の担体上への堆積を行なったとこ
ろ、有効堆積部92％、テーパー部８％の直径が150mmφ
である多孔質ガラス母材が得られ、このものの平均堆積
収率は75％であった。Then, two oxyhydrogen flame burners are installed at the center of the apparatus so that the interval between the burners is 125 mm, which is five times the burner diameter ((B) in the figure). Reciprocate at a speed of 300 g / h of silicon tetrachloride (SiCl 4 ) and oxygen gas.
At 4 m 3 / h, hydrogen gas was supplied at 4 m 3 / h to ignite, silica fine particles generated by hydrolysis of SiCl 4 in this flame were deposited on the carrier, and this burner approached both ends of the carrier At this time ((A) and (C) in the figure), the interval between these two burners is set to 40 mm, which is three times or less the burner diameter.
When the glass particles were deposited on the carrier for 10 hours, the effective deposition area was 92% and the diameter of the tapered section 8% was 150 mmφ.
Was obtained, and its average deposition yield was 75%.
しかし、比較のためにこの２本のバーナー間隔をバー
ナー径の３倍である75mmに固定したほかは上記と同様に
処理したところ、得られた多孔質ガラス母材の有効堆積
部は84％でテーパー部は16％であり、このときのシリカ
微粒子の平均堆積収率は50％となった。However, for the purpose of comparison, the same process was performed except that the distance between these two burners was fixed to 75 mm, which is three times the burner diameter, and the effective deposition portion of the obtained porous glass base material was 84%. The tapered portion was 16%, and the average deposition yield of the silica fine particles at this time was 50%.
（発明の効果） 本発明は光ファイバ多孔質ガラス母材の製造法に関す
るものであり、これは前記したように複数の酸水素火炎
バーナーを用いるCVD法において、この２本のバーナー
間隔を有効堆積部においてはバーナー径の４倍以上と
し、テーパー部ではこれをバーナー径の３倍以下とする
ものであるが、これによればテーパー部を最小とするこ
とができるし、有効堆積部ではバーナー火炎同志の干渉
がなくなるのでこの堆積収率を85％以上とすることがで
き、平均堆積収率を上げることができるという工業的な
有利性が与えられる。(Effects of the Invention) The present invention relates to a method for producing an optical fiber porous glass preform, and as described above, in a CVD method using a plurality of oxyhydrogen flame burners, the effective deposition between the two burners is performed. In the part, the burner diameter is set to four times or more, and in the taper part, the diameter is set to three times or less. However, according to this, the taper part can be minimized, and the burner flame in the effective deposition part. Since there is no interference between competitors, the deposition yield can be made 85% or more, which gives an industrial advantage that the average deposition yield can be increased.
第１図は本発明の方法に使用されるCVD法による多孔質
ガラス母材製造装置の縦断面図を示したものであり、第
２図はバーナー間隙と堆積効率との関係図、第３図はバ
ーナー間隙とテーパー部の長さとの関係図を示したもの
である。１ ……光ファイバ多孔質母材 ２……担体 ３−１ ３−２……酸水素火炎バーナー ４……ガラス微粒子、５……バーナー台 ｌ……バーナー間隔、ｄ……バーナー径FIG. 1 is a longitudinal sectional view of a porous glass preform manufacturing apparatus by a CVD method used in the method of the present invention. FIG. 2 is a view showing the relationship between burner gap and deposition efficiency. FIG. 4 shows a relationship diagram between the burner gap and the length of the tapered portion. DESCRIPTION OF SYMBOLS 1 ... Optical fiber porous preform 2 ... Carrier 3-1 3-2 ... Oxy-hydrogen flame burner 4 ... Glass fine particle 5, ... Burner stand l ... Burner interval, d ... Burner diameter
Claims (1)
り担体上にガラス微粒子を堆積させた光ファイバ多孔質
母材の製造方法において、該バーナーの間隔をガラス微
粒子堆積の有効堆積部においてはバーナー径の４倍以上
とし、テーパー部においてはバーナー径の３倍以下とす
ることを特徴とする光ファイバ多孔質母材の製造方法。In a method of manufacturing an optical fiber porous preform in which glass fine particles are deposited on a carrier by an external CVD method using a plurality of burners, the distance between the burners is set to an effective deposition part for glass fine particle deposition. A method for producing a porous optical fiber preform, characterized in that the diameter is at least four times the burner diameter and at the taper portion is three times or less the burner diameter.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1247225A JP2612941B2 (en) | 1989-09-22 | 1989-09-22 | Method for producing porous optical fiber preform |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1247225A JP2612941B2 (en) | 1989-09-22 | 1989-09-22 | Method for producing porous optical fiber preform |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH03109231A JPH03109231A (en) | 1991-05-09 |
| JP2612941B2 true JP2612941B2 (en) | 1997-05-21 |
Family
ID=17160317
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1247225A Expired - Lifetime JP2612941B2 (en) | 1989-09-22 | 1989-09-22 | Method for producing porous optical fiber preform |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2612941B2 (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2791663B1 (en) * | 1999-04-01 | 2001-06-29 | Cit Alcatel | PROCESS FOR MANUFACTURING A REFORM FOR FIBER OPTICS AND MORE PARTICULARLY A PREFORM OF HIGH STRENGTH |
| DE60019029T2 (en) | 1999-07-02 | 2006-02-16 | Shin-Etsu Chemical Co., Ltd. | Method and apparatus for producing a glass optical fiber preform by the external deposition method |
| DE10047100B4 (en) * | 2000-09-21 | 2004-09-30 | Heraeus Tenevo Ag | Method and device for producing a cylinder made of doped quartz glass |
| BR0107776A (en) * | 2000-11-24 | 2002-11-12 | Sumitomo Electric Industries | Production method for depositing glass particles and apparatus used for this purpose |
| JP3512027B2 (en) * | 2001-09-20 | 2004-03-29 | 住友電気工業株式会社 | Method for producing porous base material |
| WO2007073031A1 (en) * | 2005-12-19 | 2007-06-28 | Ls Cable Ltd. | Method for fabricating optical fiber preform with low oh concentration using mcvd process |
| KR101695400B1 (en) * | 2015-11-03 | 2017-01-23 | 주식회사 아론 | Manufacturing device for optical fiber preform |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0383831A (en) * | 1989-08-25 | 1991-04-09 | Fujikura Ltd | Preparation of optical fiber base material |
-
1989
- 1989-09-22 JP JP1247225A patent/JP2612941B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH03109231A (en) | 1991-05-09 |
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