JP2582592B2 - Method for manufacturing base material for optical functional element - Google Patents
Method for manufacturing base material for optical functional elementInfo
- Publication number
- JP2582592B2 JP2582592B2 JP62252287A JP25228787A JP2582592B2 JP 2582592 B2 JP2582592 B2 JP 2582592B2 JP 62252287 A JP62252287 A JP 62252287A JP 25228787 A JP25228787 A JP 25228787A JP 2582592 B2 JP2582592 B2 JP 2582592B2
- Authority
- JP
- Japan
- Prior art keywords
- base material
- optical fiber
- rare earth
- optical functional
- functional element
- 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 - Fee Related
Links
- 239000000463 material Substances 0.000 title claims description 25
- 238000000034 method Methods 0.000 title claims description 20
- 238000004519 manufacturing process Methods 0.000 title claims description 12
- 230000003287 optical effect Effects 0.000 title claims description 11
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 claims description 21
- 229910052761 rare earth metal Inorganic materials 0.000 claims description 16
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 11
- 239000011521 glass Substances 0.000 claims description 6
- 150000002910 rare earth metals Chemical class 0.000 claims description 6
- 239000010419 fine particle Substances 0.000 claims description 4
- 239000013307 optical fiber Substances 0.000 description 24
- 239000000835 fiber Substances 0.000 description 3
- 238000005245 sintering Methods 0.000 description 3
- 238000009826 distribution Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005470 impregnation Methods 0.000 description 2
- 230000010355 oscillation Effects 0.000 description 2
- 238000004017 vitrification Methods 0.000 description 2
- 229910005793 GeO 2 Inorganic materials 0.000 description 1
- 229910052779 Neodymium Inorganic materials 0.000 description 1
- 238000002835 absorbance Methods 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 230000000996 additive effect Effects 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 239000001307 helium Substances 0.000 description 1
- 229910052734 helium Inorganic materials 0.000 description 1
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 description 1
- 238000007654 immersion Methods 0.000 description 1
- QEFYFXOXNSNQGX-UHFFFAOYSA-N neodymium atom Chemical compound [Nd] QEFYFXOXNSNQGX-UHFFFAOYSA-N 0.000 description 1
- ATINCSYRHURBSP-UHFFFAOYSA-K neodymium(iii) chloride Chemical compound Cl[Nd](Cl)Cl ATINCSYRHURBSP-UHFFFAOYSA-K 0.000 description 1
- 239000010453 quartz Substances 0.000 description 1
- -1 rare earth chloride Chemical class 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 239000004071 soot Substances 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]
- C03B37/01413—Reactant delivery systems
- C03B37/01433—Reactant delivery systems for delivering and depositing additional reactants as liquids or solutions, e.g. for solution doping of the porous glass preform
-
- 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
- C03B2201/30—Doped silica-based glasses doped with metals, e.g. Ga, Sn, Sb, Pb or Bi
- C03B2201/34—Doped silica-based glasses doped with metals, e.g. Ga, Sn, Sb, Pb or Bi doped with rare earth metals, i.e. with Sc, Y or lanthanides, e.g. for laser-amplifiers
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Geochemistry & Mineralogy (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Chemical & Material Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Glass Compositions (AREA)
- Glass Melting And Manufacturing (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、例えば光ファイバレーザ、増幅器、光ファ
イバセンサ等の機能性ファイバ等、光機能素子を得るた
めの母材を製造する方法に関するものである。Description: TECHNICAL FIELD The present invention relates to a method for manufacturing a base material for obtaining an optical functional element such as a functional fiber such as an optical fiber laser, an amplifier and an optical fiber sensor. It is.
（従来技術及びその問題点） 光機能素子の一例として機能性ファイバがある。この
機能性ファイバとは、例えば光ファイバレーザや光ファ
イバ増幅器や光ファイバセンサ等であり、通常の光ファ
イバのコアに希土類元素をドーピングしたものである。
このような希土類元素等をドーピングした光ファイバの
母材の製造方法として、従来、例えば特開昭62−59535
号公報に記載されているように、VAD法により母材を製
造するに際して、１気圧を超える添加剤含有雰囲気ガス
中で多孔質母材を焼結して透明ガラス化することにより
希土類元素等をドーピングする方法があった。また浸漬
による方法が特開昭56−73638号公報に記載されてい
る。(Prior Art and Problems) There is a functional fiber as an example of the optical functional element. The functional fiber is, for example, an optical fiber laser, an optical fiber amplifier, an optical fiber sensor, or the like, and is obtained by doping a normal optical fiber core with a rare earth element.
As a method for producing a base material of such an optical fiber doped with a rare earth element or the like, conventionally, for example, Japanese Patent Application Laid-Open No. 62-59535
As described in the publication, when manufacturing a base material by the VAD method, a rare earth element or the like is obtained by sintering a porous base material in an additive-containing atmosphere gas exceeding 1 atm to form a transparent glass. There was a method of doping. A method by immersion is described in JP-A-56-73638.
しかしながら、このような従来の方法では、いずれに
しても高濃度に希土類元素をドーピングすることができ
ないという不都合があった。However, such a conventional method has a disadvantage that a rare earth element cannot be doped at a high concentration in any case.
（問題点を解決するための手段） 上記問題点を解決するため、本発明の光機能素子用母
材の製造方法は、VAD法によりガラス微粒子の半焼結体
である多孔質母材を作製し、この多孔質母材に希土類ア
ルコール溶液を含浸させ、これを乾燥させてアルコール
を蒸発させた後、焼結することによりガラス化するもの
である。(Means for Solving the Problems) In order to solve the above problems, the method for producing a base material for an optical functional device of the present invention comprises producing a porous base material which is a semi-sintered body of glass fine particles by a VAD method. Then, the porous base material is impregnated with a rare earth alcohol solution, dried and evaporated to evaporate the alcohol, and then sintered to be vitrified.
（実施例） 以下、本発明の一実施例を第１図〜第４図に基づいて
説明する。(Embodiment) An embodiment of the present invention will be described below with reference to FIGS.
第１図は本発明の一実施例における光機能素子用母材
の製造方法の工程説明図で、本実施例では希土類元素と
してNd（ネオジム）をドーピングした単一モード光ファ
イバのコアの母材を製造する。まず、工程１において、
周知のVAD法（Vaper Phase Axial Deposition）により
ガラス微粒子の半焼結体である多孔質母材（スート）を
作製する。このとき、屈折率制御のためにGeO2等を添加
することも可能である。次に工程２において、NdCl
3（塩化ネオジム）のメタノール溶液に前記多孔質母材
を室温にて24時間程度浸漬する。なお、希土類塩化物は
アルコールに溶けやすいので、この溶液は容易に作製で
きる。次に工程３において、前記多孔質母材を室温にて
１週間程度放置し、メタノールを蒸発させる。これによ
り、多孔質母材にNdCl3が沈着する。次に工程４におい
て、通常の1500℃程度のHe（ヘリウム）雰囲気条件にて
焼結し、透明ガラス化を行なう。これにより光ファイバ
のコア母材（コアロッド）か完成する。FIG. 1 is a process explanatory view of a method of manufacturing a preform for an optical functional device according to one embodiment of the present invention. In this embodiment, a preform of a core of a single mode optical fiber doped with Nd (neodymium) as a rare earth element is shown. To manufacture. First, in step 1,
A porous base material (soot), which is a semi-sintered body of glass fine particles, is prepared by a well-known VAD method (Vaper Phase Axial Deposition). At this time, GeO 2 or the like can be added for controlling the refractive index. Next, in step 2, NdCl
3 Immerse the porous base material in a methanol solution of (neodymium chloride) at room temperature for about 24 hours. Since the rare earth chloride is easily dissolved in alcohol, this solution can be easily prepared. Next, in step 3, the porous base material is left at room temperature for about one week to evaporate methanol. Thereby, NdCl 3 is deposited on the porous base material. Next, in step 4, sintering is performed under normal He (helium) atmosphere conditions of about 1500 ° C., and vitrification is performed. Thereby, the core preform (core rod) of the optical fiber is completed.
以上の手順により、外径10mm、長さ200mmのコアロッ
ドを、NdCl3メタノール溶液の濃度を種々に変えた多数
製作した。そして溶液の濃度とNdのドープ量との関係を
調べたところ、第２図のような結果が得られた。すなわ
ち、溶液の濃度が大きいほどドープ量も大きくなり、ほ
ぼ２重量％の濃度の時に最大20000p.p.m.までの高濃度
ドーピングが可能であった。これ以上のドープ量では、
透明ガラス化が困難であった。なお、ドープ量は波長0.
8μｍの光の吸光度より求めた。また、作製したコアロ
ッドの両端のドープ量の変動を調べた結果、10％以内に
収まっており、均一にドーピングされていることが確認
された。By the above procedure, a large number of core rods having an outer diameter of 10 mm and a length of 200 mm were manufactured with various concentrations of the NdCl 3 methanol solution. When the relationship between the concentration of the solution and the doping amount of Nd was examined, the results shown in FIG. 2 were obtained. That is, the higher the concentration of the solution, the larger the doping amount. At a concentration of approximately 2% by weight, high-concentration doping up to 20,000 ppm was possible. With a higher doping amount,
Transparent vitrification was difficult. The doping amount is wavelength 0.
It was determined from the absorbance of 8 μm light. In addition, as a result of examining the fluctuation of the doping amount at both ends of the manufactured core rod, it was found to be within 10%, and it was confirmed that the doping was uniform.
次に、上記コアロッドのうち、2000p.p.m.の濃度にド
ーピングされたコアロッド（比屈折率差ΔＮ＝0.8％）
の屈折率分布を調べたところ、第３図のようであつた。
さらにこのコアロッドに純粋石英クラッド層を合成し、
コア径5.0μｍの光ファイバを作製して損失波長特性を
調べたところ、第４図のようであった。すなわち第４図
（Ａ）のように、波長0.4〜1.0μｍの範囲では高濃度の
Ndによる吸収が見られた。また第４図（Ｂ）のように、
波長1.0〜1.2μｍの範囲では3dB/km以下の低損失値を示
しており、使用したメタノールの影響は全く認められな
かった。Next, of the above core rods, a core rod doped at a concentration of 2000 ppm (relative refractive index difference ΔN = 0.8%)
When the refractive index distribution was examined, it was as shown in FIG.
Furthermore, a pure quartz clad layer is synthesized on this core rod,
When an optical fiber having a core diameter of 5.0 μm was manufactured and loss wavelength characteristics were examined, it was as shown in FIG. That is, as shown in FIG. 4 (A), in the wavelength range of 0.4 to 1.0 μm,
Absorption by Nd was observed. Also, as shown in FIG.
A low loss value of 3 dB / km or less was shown in the wavelength range of 1.0 to 1.2 μm, and the effect of methanol used was not recognized at all.
このように、VAD法と含浸法との有機的な組合わせに
より、希土類元素が極めて高濃度にしかも均一にドーピ
ングされた光機能素子用母材を製造できる。したがって
この母材を用いて例えば単一モードの光ファイバを製作
することにより、高濃度ドーピングのしかも低損失の光
ファイバを得ることができ、さらにはこの光ファフイバ
を光ファイバレーザとして用いることにより、高濃度ド
ーピングが可能であることから発振効率が向上し、小形
化を実現できる。また、VAD法を利用したので極めて大
きな母材を製造でき、したがって光ファイバの外にも各
種の光機能素子に使用でき、その利用範囲を大幅に拡大
できる。特に本実施例の場合、NdCl3メタノール溶液の
濃度をNdCl3の重量％で0.5〜２にすることにより、ドー
ピングの濃度を10000〜20000p.p.m.程度の極めて高い濃
度にすることができ、非常に好ましい。As described above, by the organic combination of the VAD method and the impregnation method, a base material for an optical functional element in which a rare earth element is doped at an extremely high concentration and uniformly can be manufactured. Therefore, for example, by manufacturing a single-mode optical fiber using this base material, it is possible to obtain a high-concentration doping and low-loss optical fiber, and further, by using this optical fiber as an optical fiber laser, Since high-concentration doping is possible, oscillation efficiency is improved, and downsizing can be realized. In addition, since the VAD method is used, an extremely large preform can be manufactured, so that it can be used for various optical functional elements besides optical fibers, and the range of use can be greatly expanded. Especially in the case of this embodiment, by 0.5 to 2 concentration of NdCl 3 methanol in weight percent of NdCl 3, can be the concentration of the doping to a very high concentration of about 10000～20000P.Pm, very preferable.
（別の実施例） 上記実施例においては、ドーピングする希土類元素と
してNdを用いた例について説明したが、本発明はこれに
限定されるものではなく。他のいかなる希土類元素をド
ーピングする場合であっても本発明を用いることができ
る。(Another Example) In the above example, an example was described in which Nd was used as the rare earth element to be doped, but the present invention is not limited to this. The present invention can be used for doping with any other rare earth element.
また上記実施例においては、アルコールとしてメタノ
ールを用いた例について説明したが、本発明はこれに限
定されるものではなく、他のいかなるアルコールを用い
てもよい。Further, in the above-described embodiment, an example in which methanol is used as the alcohol has been described. However, the present invention is not limited to this, and any other alcohol may be used.
また上記実施例においては、光ファイバのコア母材を
製造した例について説明したが、本発明はこれに限定さ
れるものではなく、コアとクラッドとを含めた光ファイ
バ全体の母材を製造することもでき、さらには光ファイ
バ以外の光機能素子の母材を製造することもできる。Further, in the above embodiment, the example in which the core preform of the optical fiber was manufactured was described, but the present invention is not limited to this, and the preform of the entire optical fiber including the core and the clad was manufactured. It is also possible to manufacture a base material of an optical functional element other than an optical fiber.
（発明の効果） 以上説明したように、本発明によれば、VAD法により
ガラス微粒子の半焼結体である多孔質母材を作製し、こ
の多孔質母材に希土類アルコール溶液を含浸させ、これ
を乾燥させてアルコールを蒸発させた後、焼結すること
によりガラス化するので、VAD法と含浸法との有機的な
組合わせにより、希土類元素が極めて高濃度にしかも均
一にドーピングされた光機能素子用母材を製造できる。
したがってこの母材を用いて例えば単一モードの光ファ
イバを製作することにより、高濃度ドーピングのしかも
低損失の光ファイバを得ることができ、さらにはこの光
ファイバを光ファイバレーザとして用いることにより、
高濃度ドーピングが可能であることから発振効率が向上
し、小形化を実現できる。また、VAD法を利用したので
極めて大きな母材を製造でき、したがって光ファイバの
外にも各種の光機能素子に使用でき、その利用範囲を大
幅に拡大できる。(Effects of the Invention) As described above, according to the present invention, a porous base material, which is a semi-sintered body of glass fine particles, is prepared by the VAD method, and the porous base material is impregnated with a rare earth alcohol solution. After drying and evaporating the alcohol, the glass is vitrified by sintering. By using an organic combination of the VAD method and the impregnation method, the rare earth element can be doped at a very high concentration and uniformly. A base material for an element can be manufactured.
Therefore, for example, by manufacturing a single-mode optical fiber using this base material, it is possible to obtain a high-concentration doping and low-loss optical fiber, and further, by using this optical fiber as an optical fiber laser,
Since high-concentration doping is possible, oscillation efficiency is improved, and downsizing can be realized. In addition, since the VAD method is used, an extremely large preform can be manufactured, so that it can be used for various optical functional elements besides optical fibers, and the range of use can be greatly expanded.
第１図は本発明の一実施例における光機能素子用母材の
製造方法の工程説明図、第２図は第１図の工程により得
られた母材の希土類アルコール溶液濃度と希土類ドープ
量との関係の説明図、第３図は同母材の屈折率分布の説
明図、第４図は同母材により製作されたコアを有する光
ファイバの損失波長特性の説明図である。FIG. 1 is a process explanatory view of a method of manufacturing a base material for an optical functional device according to an embodiment of the present invention, and FIG. 2 is a diagram showing a rare earth alcohol solution concentration and a rare earth dope amount of the base material obtained by the process of FIG. FIG. 3 is an explanatory view of a refractive index distribution of the base material, and FIG. 4 is an explanatory view of a loss wavelength characteristic of an optical fiber having a core manufactured by the base material.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 林 徳治 兵庫県伊丹市池尻４丁目３番地 三菱電 線工業株式会社伊丹製作所内 (72)発明者 吉田 実 兵庫県伊丹市池尻４丁目３番地 三菱電 線工業株式会社伊丹製作所内 (72)発明者 田中 紘幸 兵庫県伊丹市池尻４丁目３番地 三菱電 線工業株式会社伊丹製作所内 (72)発明者 新谷 健 兵庫県伊丹市池尻４丁目３番地 三菱電 線工業株式会社伊丹製作所内 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tokuharu Hayashi 4-3 Ikejiri, Itami-shi, Hyogo Mitsubishi Electric Wire Industry Co., Ltd. Itami Works (72) Inventor Minoru Yoshida 4-3-3 Ikejiri, Itami-shi, Hyogo Mitsubishi Electric (72) Inventor Hiroyuki Tanaka 4-33 Ikejiri, Itami-shi, Hyogo Mitsubishi Electric Corporation (72) Inventor Takeshi Kenya 4-43, Ikejiri, Itami-shi, Hyogo Mitsubishi Electric Wire Industry Co., Ltd. Itami Works
Claims (2)
る多孔質母材を作製し、この多孔質母材に希土類アルコ
ール溶液を含浸させ、これを乾燥させてアルコールを蒸
発させた後、焼結することによりガラス化することを特
徴とする光機能素子用母材の製造方法。1. A porous preform which is a semi-sintered body of glass fine particles is prepared by a VAD method, a rare earth alcohol solution is impregnated in the porous preform, and the porous preform is dried to evaporate the alcohol. A method for producing a base material for an optical functional element, comprising vitrifying by tying.
溶液として、NdCl3を0.5〜２重量％含んだメタノールを
用いる特許請求の範囲第１項に記載の光機能素子用母材
の製造方法。2. The method according to claim 1, wherein the rare earth alcohol solution impregnated in the porous base material is methanol containing 0.5 to 2% by weight of NdCl 3 .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62252287A JP2582592B2 (en) | 1987-10-06 | 1987-10-06 | Method for manufacturing base material for optical functional element |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62252287A JP2582592B2 (en) | 1987-10-06 | 1987-10-06 | Method for manufacturing base material for optical functional element |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0196021A JPH0196021A (en) | 1989-04-14 |
| JP2582592B2 true JP2582592B2 (en) | 1997-02-19 |
Family
ID=17235155
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62252287A Expired - Fee Related JP2582592B2 (en) | 1987-10-06 | 1987-10-06 | Method for manufacturing base material for optical functional element |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2582592B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2828284B2 (en) * | 1989-11-13 | 1998-11-25 | 株式会社フジクラ | Method for producing rare earth element doped glass |
| JP2766420B2 (en) * | 1992-04-07 | 1998-06-18 | 株式会社フジクラ | Method for producing erbium-doped quartz |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS583980A (en) * | 1981-06-30 | 1983-01-10 | エリス・テイ−・クレイトン | Portable mechanical plating device and plating method thereby |
| JPS6259535A (en) * | 1985-09-06 | 1987-03-16 | Nippon Telegr & Teleph Corp <Ntt> | Production of quartz glass and apparatus therefor |
-
1987
- 1987-10-06 JP JP62252287A patent/JP2582592B2/en not_active Expired - Fee Related
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS583980A (en) * | 1981-06-30 | 1983-01-10 | エリス・テイ−・クレイトン | Portable mechanical plating device and plating method thereby |
| JPS6259535A (en) * | 1985-09-06 | 1987-03-16 | Nippon Telegr & Teleph Corp <Ntt> | Production of quartz glass and apparatus therefor |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0196021A (en) | 1989-04-14 |
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