JPS6054939A - Manufacture of preform rod for single mode fiber - Google Patents
Manufacture of preform rod for single mode fiberInfo
- Publication number
- JPS6054939A JPS6054939A JP16230083A JP16230083A JPS6054939A JP S6054939 A JPS6054939 A JP S6054939A JP 16230083 A JP16230083 A JP 16230083A JP 16230083 A JP16230083 A JP 16230083A JP S6054939 A JPS6054939 A JP S6054939A
- Authority
- JP
- Japan
- Prior art keywords
- rod
- quartz
- dopant
- quartz tube
- quartz rod
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000000835 fiber Substances 0.000 title claims abstract description 15
- 238000004519 manufacturing process Methods 0.000 title claims description 10
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims abstract description 62
- 239000010453 quartz Substances 0.000 claims abstract description 59
- 239000002019 doping agent Substances 0.000 claims abstract description 25
- 239000007787 solid Substances 0.000 claims abstract description 3
- 238000000034 method Methods 0.000 claims description 15
- 230000002093 peripheral effect Effects 0.000 claims description 7
- 238000007711 solidification Methods 0.000 claims 1
- 230000008023 solidification Effects 0.000 claims 1
- 235000012239 silicon dioxide Nutrition 0.000 abstract description 54
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 abstract description 10
- 238000010438 heat treatment Methods 0.000 abstract description 9
- 239000007789 gas Substances 0.000 abstract description 7
- 229910052786 argon Inorganic materials 0.000 abstract description 5
- 239000004071 soot Substances 0.000 abstract description 5
- 239000000463 material Substances 0.000 abstract description 4
- 238000001704 evaporation Methods 0.000 abstract description 3
- 239000011521 glass Substances 0.000 abstract description 3
- 238000000151 deposition Methods 0.000 abstract description 2
- 239000002994 raw material Substances 0.000 abstract description 2
- 229910052681 coesite Inorganic materials 0.000 abstract 1
- 229910052906 cristobalite Inorganic materials 0.000 abstract 1
- 230000003247 decreasing effect Effects 0.000 abstract 1
- 230000008020 evaporation Effects 0.000 abstract 1
- 230000008018 melting Effects 0.000 abstract 1
- 238000002844 melting Methods 0.000 abstract 1
- 239000000377 silicon dioxide Substances 0.000 abstract 1
- 229910052682 stishovite Inorganic materials 0.000 abstract 1
- 229910052905 tridymite Inorganic materials 0.000 abstract 1
- 238000005253 cladding Methods 0.000 description 14
- 238000006243 chemical reaction Methods 0.000 description 4
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 description 3
- 229910001882 dioxygen Inorganic materials 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- VXEGSRKPIUDPQT-UHFFFAOYSA-N 4-[4-(4-methoxyphenyl)piperazin-1-yl]aniline Chemical compound C1=CC(OC)=CC=C1N1CCN(C=2C=CC(N)=CC=2)CC1 VXEGSRKPIUDPQT-UHFFFAOYSA-N 0.000 description 1
- SDTHIDMOBRXVOQ-UHFFFAOYSA-N 5-[bis(2-chloroethyl)amino]-6-methyl-1h-pyrimidine-2,4-dione Chemical compound CC=1NC(=O)NC(=O)C=1N(CCCl)CCCl SDTHIDMOBRXVOQ-UHFFFAOYSA-N 0.000 description 1
- 244000205754 Colocasia esculenta Species 0.000 description 1
- 235000006481 Colocasia esculenta Nutrition 0.000 description 1
- 229910004014 SiF4 Inorganic materials 0.000 description 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 239000005049 silicon tetrachloride Substances 0.000 description 1
- ABTOQLMXBSRXSM-UHFFFAOYSA-N silicon tetrafluoride Chemical compound F[Si](F)(F)F ABTOQLMXBSRXSM-UHFFFAOYSA-N 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B37/00—Manufacture or treatment of flakes, fibres, or filaments from softened glass, minerals, or slags
- C03B37/01—Manufacture of glass fibres or filaments
- C03B37/012—Manufacture of preforms for drawing fibres or filaments
- C03B37/014—Manufacture of preforms for drawing fibres or filaments made entirely or partially by chemical means, e.g. vapour phase deposition of bulk porous glass either by outside vapour deposition [OVD], or by outside vapour phase oxidation [OVPO] or by vapour axial deposition [VAD]
- C03B37/018—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] by glass deposition on a glass substrate, e.g. by inside-, modified-, plasma-, or plasma modified- chemical vapour deposition [ICVD, MCVD, PCVD, PMCVD], i.e. by thin layer coating on the inside or outside of a glass tube or on a glass rod
- C03B37/01861—Means for changing or stabilising the diameter or form of tubes or rods
- C03B37/01869—Collapsing
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)
Abstract
Description
【発明の詳細な説明】
（発明の技術分野）
本発明は、純石英コアを有するシングルモードファイバ
を得るためのプリフォーノ・ロッドの製造方法に関する
。TECHNICAL FIELD OF THE INVENTION The present invention relates to a method for manufacturing a preforno rod for obtaining a single mode fiber with a pure quartz core.
（発明の技術的背景とその問題点）
従来、シングルモードファイバ用のプリフォームロッド
は、ターゲ、−，１・にその＠１１方向にスートを堆積
させる軸伺は法により製造されている。しかし、この軸
付け法では、Ｇｅ等の高ｂｉｔ 、１）ｊ率ドーパント
を含むコア部をイｊするプリフォーノ・ロッドは比較的
容易に作成すること１」できるが、例えば、耐放射線用
ファイバを１！するための純石英コア部を有するプリフ
ォームロッドはその作成が非常に困雌である。(Technical Background of the Invention and Problems Therewith) Conventionally, preform rods for single mode fibers have been manufactured by a shafting method in which soot is deposited in the @11 direction on targets, -, 1, and so on. However, with this axial mounting method, it is relatively easy to create a preforno rod with a high-bit content such as Ge and a core containing a j-rate dopant. 1! Preform rods with pure quartz cores for this purpose are extremely difficult to manufacture.
そこで、従来は石英／ｉ；に高純度の四ｊ１１化ケイ素
（Ｓ ｉ Ｃ１４）を導入し、管内に純石英ガラス層を
形成する内付け法により純石英コア部を有するプリフォ
ームロッドを製造することが行われている。しかし、こ
の内封は法では、純石英コア部を形成するために５ｉＣ
ｕ４のみを熱酸化反応させることから、１７００℃以」
−の反応温度が必要となるので、純石英コア部の成形中
に石英管が収縮してしまうという欠点を有する。従って
、この方法においては石英管の収縮を防止するための種
々の手段及び装置が不可欠である。また、ドーパントを
含まない四酸化ケイ素のみではその反応速度が遅いので
、プリフォームロッドの製造に多大の時間を要してしま
う。Therefore, conventionally, a preform rod having a pure quartz core is manufactured by an internal attachment method in which high-purity silicon tetrachloride (S i C14) is introduced into quartz/i and a pure silica glass layer is formed inside the tube. things are being done. However, this inner sealing method requires 5iC to form a pure quartz core.
1700℃ or higher because only U4 undergoes a thermal oxidation reaction.
Since a reaction temperature of - is required, there is a drawback that the quartz tube shrinks during molding of the pure quartz core. Therefore, various means and devices for preventing shrinkage of the quartz tube are essential in this method. Furthermore, since the reaction rate of silicon tetroxide alone without a dopant is slow, it takes a lot of time to manufacture the preform rod.
その他、純石英コア林に低屈折率ドーパントを含む５ｉ
Ｃｕ４スートを吹き付けるロッドインチューブ法にて純
石英コア部を有するプリフォームロッドを製造すること
も行われているが、かかる方法では、水分の極めて少な
い良質の純石英コア林を用いなければならないので、材
料費がその分だけ高くなってしまう。また、この方法に
より得られたロッドからシングルモードファイバを作成
すると、通常、コアとクラッドとの界面が不完全になる
ことが多いことから構造散乱が大きくなってしまい、長
波長で低損失のファイバを得ることは困難である。In addition, 5i containing low refractive index dopant in pure quartz core forest
Preform rods with pure quartz cores have also been manufactured using the rod-in-tube method of spraying Cu4 soot, but this method requires the use of high-quality pure quartz core forests with extremely low moisture content. , the material cost will increase accordingly. In addition, when single-mode fibers are made from rods obtained by this method, the interface between the core and cladding is often incomplete, resulting in large structural scattering, resulting in long-wavelength, low-loss fibers. is difficult to obtain.
（発明の目的）
本発明の目的は、安価な材料を用いて簡単かつ短時間で
特性の優れた純石英コアを有するシングルモードファイ
バが得られるプリフォームロッドを製造するための方法
を提供することにある。(Objective of the Invention) An object of the present invention is to provide a method for manufacturing a preform rod that can easily and quickly produce a single mode fiber having a pure quartz core with excellent characteristics using inexpensive materials. It is in.
（発明の概要）
本発明は、低屈折率ドーパントを含む石英管を加熱する
ことでその内周面から低屈折率ドーパントを蒸発させて
内周面に純石英層を形成すると共に石英管を中実化する
ことを特徴とする。(Summary of the Invention) The present invention heats a quartz tube containing a low refractive index dopant to evaporate the low refractive index dopant from the inner peripheral surface to form a pure quartz layer on the inner peripheral surface, and at the same time, the quartz tube is heated. It is characterized by materialization.
（発明の実施例） 以下、本発明の実施例を図面を参照１．て説明する。(Example of the invention) Hereinafter, embodiments of the present invention will be described with reference to the drawings.1. I will explain.
先ず、第１図に示すように、タロ￥２０＋＋ｓ、肉厚１
．５＋ｗｍの天然石英管１を用意し、この石英管ｌを図
示しないガラス旋盤に取す付げた後１分間に数十回転の
速度で回転させた。そして、同時にこの石英管ｌに、Ｓ
Ｉ ＣＪＬ４１００ＣＣ／ｌ１ｉｎ 、Ｓ ＩＦ４２
００ ｃｃ／ｗｉｎを一定で導入すると共に反応用酸素
ガス０２を２０００ ｃｃ／ ｍａｉｎで導入し、石英
管ｌの軸方向に沿って酸水素バーナ（図示せず）をｌ
ＯＯｍｖｍ／ ｌ１ｉｎの速度で移動させ、石英管１の
外壁を１５５０℃にて連続的に加熱した。この加熱によ
り５ｉＣｕ４及びドーパン）Ｆを有するＳｉＦ４が酸素
ガス０２と反応し、Ｆを含む５ｉ０２スートが石英管１
の内周面に堆積すると共に溶融され、ガラス化された。First, as shown in Figure 1, taro ¥20++s, wall thickness 1
．． A 5+wm natural quartz tube 1 was prepared, and after being attached to a glass lathe (not shown), the quartz tube 1 was rotated at a speed of several tens of revolutions per minute. At the same time, S
I CJL4100CC/l1in, S IF42
00 cc/win was introduced at a constant rate, and reaction oxygen gas 02 was introduced at 2000 cc/main, and an oxyhydrogen burner (not shown) was installed along the axial direction of the quartz tube.
The outer wall of the quartz tube 1 was continuously heated at 1550° C. by moving at a speed of OOmvm/l1in. By this heating, SiF4 containing 5iCu4 and dopant F reacts with oxygen gas 02, and 5i02 soot containing F reacts with the quartz tube 1.
It was deposited on the inner circumferential surface of the tube and was melted and vitrified.
本実施例では上述の動作を２０回繰り返しく堆積回数２
０回）、第１図に示すように、石英管１の内周面にＦを
含むクラッド層２を形成した。In this example, the above-mentioned operation is repeated 20 times, and the number of depositions is 2.
As shown in FIG. 1, a cladding layer 2 containing F was formed on the inner peripheral surface of a quartz tube 1.
このようにして１石英管ｌにクラッド層２を設けた後は
」−記ガラス原料ガスの供給を停止し、石英管ｌにアル
ゴンガスを流して内圧を加えつつバーナを更に移動させ
、２０００℃の温度で石英管ｌを加熱した。この加熱に
よりクラッド層２の内周側のドーパン）Ｆが蒸発し、又
同時に縮径した。この加熱はバーナの往復動で数回繰り
返したので、その都度Ｆが蒸発し、かつ石英管ｌが縮径
し、クラッド層２の内周面にコア部となる純石英層が形
成された。After providing the cladding layer 2 in the quartz tube 1 in this way, the supply of glass raw material gas was stopped, argon gas was flowed through the quartz tube 1, the burner was further moved while applying internal pressure, and the temperature was raised to 2000°C. The quartz tube 1 was heated to a temperature of . Due to this heating, the dopant (F) on the inner peripheral side of the cladding layer 2 was evaporated and the diameter was reduced at the same time. This heating was repeated several times by reciprocating the burner, so that F was evaporated each time, the diameter of the quartz tube l was reduced, and a pure quartz layer serving as a core was formed on the inner peripheral surface of the cladding layer 2.
最後に、石英管ｌへのアルゴンガスの供給を停止し、収
縮した石英管１を１８００℃程ＩＷで加熱することによ
り中実化（コラプス）し、プリフォームロッドを製造し
た。Finally, the supply of argon gas to the quartz tube 1 was stopped, and the shrunken quartz tube 1 was heated to about 1800° C. with IW to collapse, thereby producing a preform rod.
このプリフォームロッドの屈折率分布を実測したところ
、第２図に示すように、クラッド層２の中央に立ち」ユ
がりの急激な高屈折の大きいコア部が形成されていた。When the refractive index distribution of this preform rod was actually measured, as shown in FIG. 2, a core portion with a high refractive index and a sharp bend was formed in the center of the cladding layer 2.
この製造したプリフォームロッドを外径１２５ＩＬｍに
紡糸したところ、コア径が７．５＃ｌ−■で屈折率差が
０．００５のシングルモードファイバを得ることができ
た。この得られたファイバは散乱損失が極めて小さかっ
た。これはクラッド層２にドーパンｌ−Ｆを蒸発させて
純石英層を一体的に形成したことでコアとクラッドとの
界面の変動が極めて小さくなって構造損失が減少したこ
とによると考えられる。When this manufactured preform rod was spun to have an outer diameter of 125 ILm, a single mode fiber with a core diameter of 7.5 #l-■ and a refractive index difference of 0.005 could be obtained. The resulting fiber had extremely low scattering loss. This is thought to be due to the fact that by evaporating dopane l-F in the cladding layer 2 and integrally forming a pure quartz layer, fluctuations at the interface between the core and the cladding become extremely small, thereby reducing structural loss.
ところで、石英管ｌ内では、−に述したように、５ｉＣ
ＪＬ４のみを反応させずにＳｉＣ見４とドーパントＦを
含む５ｔＦａとを酸素ガスと反応させているが、このよ
うにドーパントＦを含んだ状態で反応させると、反応温
度としては１４００℃〜１６００℃の低温でよく、又５
ｉＣｕ４のみの場合と比べて４〜５倍の量の５ｉＣＪ１
４を反応させることができる。従って、石英管ｌを殆ど
縮径させずに短時間でクラッド層２を形成することがで
きる。By the way, in the quartz tube l, as mentioned in -, 5iC
SiC Mi4 and 5tFa containing dopant F are reacted with oxygen gas without reacting only JL4, but when reacting in a state containing dopant F in this way, the reaction temperature is 1400 ° C to 1600 ° C It is fine at a low temperature of 5.
4-5 times the amount of 5iCJ1 compared to iCu4 alone
4 can be reacted. Therefore, the cladding layer 2 can be formed in a short time without reducing the diameter of the quartz tube l.
−Ｆ記実施例ではドーパン）Ｆを含まない天然石英管を
用いてその周面に肉付は法にてＦを含むクラッド層２を
形成しているが、予めドーパントＦを含む石英管を用意
すると、前記クラッド層２の形成工程を省略し、直接こ
の石英管を加熱してＦを内側から蒸発させることで石英
管内壁に純石英層を形成することができる。従って、プ
リフォームロッドの製造が更に簡単化され、また短時間
で行うことができる。- In the example described above, a natural quartz tube that does not contain dopant (F) is used, and a cladding layer 2 containing F is formed on the circumferential surface by a filling method, but a quartz tube containing dopant F is prepared in advance. Then, by omitting the step of forming the cladding layer 2 and directly heating the quartz tube to evaporate F from the inside, a pure quartz layer can be formed on the inner wall of the quartz tube. Therefore, the production of the preform rod is further simplified and can be carried out in a short time.
また、上記実施例ではドーパントＦを蒸発する工程とコ
ラプスする工程とを分離しているが、石英管をコラプス
するために加熱するだけでドーパントＦが蒸発するので
、コラプスと同時にドーパントＦを蒸発させるようにし
てもよい。Further, in the above embodiment, the process of evaporating the dopant F and the process of collapsing are separated, but since the dopant F is evaporated simply by heating the quartz tube to collapse, the dopant F is evaporated at the same time as the collapse. You can do it like this.
尚、低屈折率ドーパントとじてＩ」Ｆに限られず、例え
ばＢであってもよく、要は加熱により効率的に蒸発する
低Ｊｉｉｉ折率ドーパントであればよい。Note that the low refractive index dopant is not limited to I''F, but may also be B, for example, as long as it is a low JIII refractive index dopant that evaporates efficiently by heating.
（発明の効果）
本発明によれば、低屈折率ドーパントを直接又はクラッ
ド層どして含む石英管を加熱し、その内周面から前記低
屈折率ドーパントを蒸発させてコア部と成る純石英層を
形成し、かつ中実化するだけであることから、材料とし
て良質の石英管を用いる必要がなく、例えば天然石英管
を用いることができ又石英管の収縮を全く考慮せずに筒
中かつ短時間で純石英コア部を有するシングルモードフ
ァイバ用のプリフォームロッドを製造することができる
。従って、安価なシングルモードファイバを提供するこ
とができる。また、クラッド層と一体的にコア部となる
純石英層を形成するので、クラッドとコアとの界面での
構浩散＾１．の小さい優れたシングルモードファイバが
得られる。(Effects of the Invention) According to the present invention, a quartz tube containing a low refractive index dopant directly or as a cladding layer is heated, and the low refractive index dopant is evaporated from the inner peripheral surface of the pure quartz tube to form the core portion. Since it is only necessary to form a layer and make it solid, there is no need to use a high-quality quartz tube as a material.For example, a natural quartz tube can be used, and the inside of the cylinder and A preform rod for a single mode fiber having a pure quartz core can be manufactured in a short time. Therefore, an inexpensive single mode fiber can be provided. In addition, since the pure quartz layer that becomes the core part is formed integrally with the cladding layer, the structure at the interface between the cladding and the core is expanded^1. An excellent single-mode fiber with a small value can be obtained.
第１図は本発明に係る製造方法を説明するための概略図
、第２図は本発明方法により製造したプリフォームロッ
ドの屈折率分布図である。
１−−−一−−石英管、
２−−−−−−クラッド層。
第２図
第１ＭFIG. 1 is a schematic diagram for explaining the manufacturing method according to the present invention, and FIG. 2 is a refractive index distribution diagram of a preform rod manufactured by the method of the present invention. 1---1---quartz tube, 2---clad layer. Figure 2 1M
Claims (1)
周面から前記低屈折率ドーパントを蒸発させ、前記石英
管を中実化することを特徴とするシングルモードファイ
バ用プリフォームロッドの製造方法。 ２、前記石英管としてその内周面側に低屈折率ドーパン
トを含む層が形成されている石英管を用いることを特徴
とする特許請求の範囲第１項に記載のシングルモードフ
ァイバ用プリフォームロッドの製造方法。 ３、前記石英管を加熱して中実化と同時に前記低屈折率
ドーパントを蒸発させることを特徴とする特許請求の範
囲第１項に記載のシングルモードファイバ用プリフォー
ムロッドの製造方法。[Claims] 1. A single mode fiber characterized in that a quartz tube containing a low refractive index dopant is heated to evaporate the low refractive index dopant from its inner circumferential surface, thereby making the quartz tube solid. Method for manufacturing preform rods. 2. The preform rod for a single mode fiber according to claim 1, wherein a quartz tube is used as the quartz tube, and a layer containing a low refractive index dopant is formed on the inner peripheral surface of the quartz tube. manufacturing method. 3. The method of manufacturing a preform rod for a single mode fiber according to claim 1, wherein the quartz tube is heated to evaporate the low refractive index dopant at the same time as solidification.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16230083A JPS6054939A (en) | 1983-09-02 | 1983-09-02 | Manufacture of preform rod for single mode fiber |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16230083A JPS6054939A (en) | 1983-09-02 | 1983-09-02 | Manufacture of preform rod for single mode fiber |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS6054939A true JPS6054939A (en) | 1985-03-29 |
Family
ID=15751875
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP16230083A Pending JPS6054939A (en) | 1983-09-02 | 1983-09-02 | Manufacture of preform rod for single mode fiber |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6054939A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4735648A (en) * | 1984-07-25 | 1988-04-05 | Stc Plc | Optical fibre manufacture |
-
1983
- 1983-09-02 JP JP16230083A patent/JPS6054939A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4735648A (en) * | 1984-07-25 | 1988-04-05 | Stc Plc | Optical fibre manufacture |
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