JPS6120908A - Production of optical fiber consisting of mixed crystal material of metallic halide compound - Google Patents

Production of optical fiber consisting of mixed crystal material of metallic halide compound

Info

Publication number
JPS6120908A
JPS6120908A JP59142034A JP14203484A JPS6120908A JP S6120908 A JPS6120908 A JP S6120908A JP 59142034 A JP59142034 A JP 59142034A JP 14203484 A JP14203484 A JP 14203484A JP S6120908 A JPS6120908 A JP S6120908A
Authority
JP
Japan
Prior art keywords
mixed crystal
halide compound
crystal material
metallic halide
fiber
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
Application number
JP59142034A
Other languages
Japanese (ja)
Inventor
Hiroyuki Kanamori
金森　浩行
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
New Japan Radio Co Ltd
Japan Radio Co Ltd
Original Assignee
New Japan Radio Co Ltd
Japan Radio Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by New Japan Radio Co Ltd, Japan Radio Co Ltd filed Critical New Japan Radio Co Ltd
Priority to JP59142034A priority Critical patent/JPS6120908A/en
Publication of JPS6120908A publication Critical patent/JPS6120908A/en
Pending legal-status Critical Current

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]
    • C03B37/018—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
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B2201/00—Type of glass produced
    • C03B2201/80—Non-oxide glasses or glass-type compositions
    • C03B2201/84—Halide glasses other than fluoride glasses, i.e. Cl, Br or I glasses, e.g. AgCl-AgBr "glass"

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)
  • Optical Fibers, Optical Fiber Cores, And Optical Fiber Bundles (AREA)

Abstract

PURPOSE:To obtain an optical fiber which is particularly suitable for IR rays and of which the refractive index changes gradually from the core to the clad by depositing and diffusing the mixed crystal material of a metallic halide compd. or the metallic halide mixed crystal material of the compsn. different from the above-mentioned mixed crystal by evaporation on the surface of the mixed crystal material of the fiber- shaped metallic halide. CONSTITUTION:A branch pipe 14 for contg. the metallic halide 16 is provided in the central part of a straight pipe part 12 made of a thick-walled transparent quartz tube and the part 12 and 14 are arranged to be heated respectively by heaters 18, 19, by which the straight pipe part of the device is constituted. The fiber 24 made of the mixed crystal material of the metallic halide such as TlBr-TlI or AgCl-AgBr is supported between a pair of supports 20 and 22 and is supported into such straight pipe part. The inside of the pipes 12, 14 is evacuated to a vacuum and is then heated and TlBr different from the mixed crystal material 24 or AgCl-AgBr different from the mixed crystal 24 in the compsn. ratio is deposited by evaporation as the metallic halide 16, by which the optical fiber having the refractive index changing continuously from the core to the clad part is obtd. The loss in the fiber side face is thus decreased, the divergence of the light at the end face is decreased and the condensability is improved.

Description

【発明の詳細な説明】 〔発明の利用分野〕 本発明は、赤外線光ファイバとして使用される金属ハロ
ゲン化合物混晶体を素材とした光ファイバの製造方法に
関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a method for manufacturing an optical fiber made of a metal halide compound mixed crystal material used as an infrared optical fiber.

〔発明の背景〕[Background of the invention]

光ファイバは、コアのみで構成すると、ファイバの側面
から光が発散して損失が大きくなるばかりでなく、ファ
イバ端面から出射された光の発散角度が大きく、集光が
困難である。また、ファイバは、ダイスを介して押出し
形成されるため、側面を完全に滑らかに良好な状態に仕
上げることが極めて難しい。このため、ファイバの側面
における光の散乱に基づく側面の損失を無視することが
できない。従って、光ファイバは、一般に中心部のコア
と、このコアの周囲にコアとは屈折率の異なるクラッド
層を設けている。そして、金属ハロゲン化合物混晶体に
よる赤外線光ファイバにおいても、コアとクラッドとか
ら構成することＫより、集光性を上げる方法が試みられ
ている。When an optical fiber is composed of only a core, not only does light diverge from the side surfaces of the fiber, resulting in a large loss, but also the light emitted from the end face of the fiber has a large divergence angle, making it difficult to condense the light. Furthermore, since the fiber is extruded through a die, it is extremely difficult to finish the side surface completely smooth and in good condition. Therefore, side losses due to light scattering at the sides of the fiber cannot be ignored. Therefore, an optical fiber generally includes a central core and a cladding layer around the core having a refractive index different from that of the core. Also, in the case of infrared optical fibers made of metal halide compound mixed crystals, attempts have been made to improve light convergence by constructing the fibers with a core and a cladding.

クラッド層の具体的な形成方法の一つとして、ＡｌＣｌ
　−ＡｊＢｒからなるコア部の周囲Ｋ　ＡｌｌＣｌ　を
設けたファイバを押出し法によシ所定の寸法に形成する
ものがある。この方法によるときは、コア部とクラッド
部との屈折率が段階的に変化する、いわゆるステップイ
ンデックス型のファイバを得ることができるが、クラッ
ド層の屈折率が連続的に変化していくグレイテッドイン
デックス型のファイバを得ることができないという欠点
があった。As one of the specific methods for forming the cladding layer, AlCl
There is a method in which a fiber having a core made of -AjBr and a circumference K AllCl is formed into a predetermined size by an extrusion method. When this method is used, it is possible to obtain a so-called step-index type fiber in which the refractive index of the core and cladding layers changes stepwise. The disadvantage was that index type fibers could not be obtained.

〔発明の目的〕[Purpose of the invention]

本発明は、コアからクラッドへ漸次屈折率が変化するグ
レイテッドインデックス型光ファイバを一得ることがで
きる金属ノ・ロゲン化合物混晶体光ファイバの製造方法
を提供することを目的とする。SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing a metal-no-rogen compound mixed crystal optical fiber, which allows obtaining a graded-index optical fiber in which the refractive index gradually changes from the core to the cladding.

〔発明の概要〕[Summary of the invention]

本発明は、コアとなる金属ノ・ロゲン化合物混晶体の表
面に、との混晶体とは異々る金属ノ・ロゲン化合物混晶
体または金属・・ロゲン化合物を蒸着、拡散させること
により、表層一部の組成比率を変化させ、コアからクラ
ッド部への屈折率が漸次変化するように構成したもので
ある。The present invention has been developed by depositing and diffusing a metal-rogen compound mixed crystal or a metal-rogen compound different from the metal-rogen compound mixed crystal on the surface of the metal-rogen compound mixed crystal that serves as the core. The refractive index from the core to the cladding portion gradually changes by changing the composition ratio of the cladding portion.

〔発明の実施例〕[Embodiments of the invention]

本発明に係る金属ハロゲン化合物混晶体光ファイバの製
造方法の好ましい実施例を、添付図面に従って詳説する
。A preferred embodiment of the method for manufacturing a metal halide mixed crystal optical fiber according to the present invention will be described in detail with reference to the accompanying drawings.

図は、本発明に係る金属ノ・ロゲ／化合物混晶体光ファ
イバを製造する装置の一例を示したものである。図にお
いて、蒸着室１０は、Ｔ字状をなしている。即ち、蒸着
室１０は、肉厚の透明石英管からなる直管部１２のほぼ
中央部に、同様の材質からなシ金属ノ・ロゲン化合物１
６を収納する枝管部１４が形成しである。そして、直管
部１２と枝管部１４との周囲にはヒータ１ｉ、ｘ９が配
設しである。また、直管部】２内には、一対の支持具２
０．２２が配置してあり、この一対の支持具２０．２２
間にＴ７Ｂｒ　−Ｔｌ工、ＡｇＣ１−ＡｊＢｒ　等の金
属ハロゲン化合物混晶体のファイバ２４を張ることがで
きるようになっている。なお、直管部１２の一端部（図
において左側端部）は封じられておシ、他端部が開口し
ていて、この開口部がパイレックスガラスによシ形成さ
れたクランク状をなすパイプ２６の一端に接続しである
。パイプ２６の８字部２８は、水槽３０内の冷却水中に
浸漬してあシ、パイプ２６の他端が図示しない真空系に
接続しである。The figure shows an example of an apparatus for producing a metal/compound mixed crystal optical fiber according to the present invention. In the figure, the deposition chamber 10 has a T-shape. That is, in the vapor deposition chamber 10, a metallogen compound 1 made of the same material is placed approximately in the center of a straight pipe part 12 made of a thick-walled transparent quartz tube.
A branch pipe portion 14 for housing the pipe 6 is formed. Heaters 1i and x9 are arranged around the straight pipe section 12 and the branch pipe section 14. In addition, a pair of supports 2 are included in the straight pipe section]2.
0.22 is arranged, and this pair of supports 20.22
A fiber 24 of a metal halide compound mixed crystal such as T7Br-Tl or AgC1-AjBr can be stretched between them. Note that one end of the straight pipe section 12 (the left end in the figure) is sealed and the other end is open, and this opening is a crank-shaped pipe 26 made of Pyrex glass. Connect it to one end. The 8-shaped portion 28 of the pipe 26 is immersed in cooling water in a water tank 30, and the other end of the pipe 26 is connected to a vacuum system (not shown).

な゛お、直管部１２は、パイプ２６に接続部材３１を介
して接続、取外しが自由となっており、まだ直管部１２
とパイプ２６との接続部３２の周囲は、シールが図られ
ている。そして、接続部３２と８字部２８との間には、
パイレックスガラスによシ構成されたコック３４が設け
てあり、蒸着室１０を真空源に連通できるようになって
いる。Note that the straight pipe section 12 can be freely connected to and removed from the pipe 26 via the connecting member 31, and the straight pipe section 12 is still connected to the pipe 26 via the connecting member 31.
The area around the connecting portion 32 between the pipe 26 and the pipe 26 is sealed. And between the connecting part 32 and the figure 8 part 28,
A cock 34 made of Pyrex glass is provided to connect the deposition chamber 10 to a vacuum source.

上記の装置を用いたグレイテッドインデックス型光ファ
イバの製造方法は次のとおりである。A method for manufacturing a graded index optical fiber using the above-mentioned apparatus is as follows.

まず、蒸着室】０の直管部１２をパイプ２６に接続し、
コック３４を開いて矢印に示す如く蒸着室ｌＯ内を排気
し、高真空にする。そして、蒸着室ｌＯ内を高真空頃維
持した状態において、ヒータ１８．１９により蒸着室１
０を約７００℃に加ｈｔｉｃｔ　　等の高純度金属ハロ
ゲン化合物１６を納置する。そして、再び蒸着室ｌＯを
パイプ２６１Ｃ接続し、蒸着室１０内を高真空に保持し
た状態において、枝管部１４をヒータ１９によシ金属ハ
ロゲ／化合物１６が昇華する温度（例えばＴｎＢｒを使
用する場合約４６０℃）に加熱し、金属ハロゲン化合物
１６を昇華させるとともに、直管部１２の内壁をヒータ
１８により加熱する。この際、昇華した金属ハロゲン化
合物１６が系外へ排出するのを防止するため、パイプ２
６の８字部２８を冷却水によシ冷却し、昇華した金属ハ
ロゲン化合物を捕獲する。First, connect the straight pipe section 12 of vapor deposition chamber 0 to the pipe 26,
The cock 34 is opened to evacuate the inside of the deposition chamber 1O as shown by the arrow to create a high vacuum. Then, in a state where the inside of the deposition chamber 1O is maintained at a high vacuum level, the heaters 18 and 19 are used to
0 to about 700°C, and a high purity metal halide compound 16 such as htict was placed therein. Then, the vapor deposition chamber IO is connected again to the pipe 261C, and while the inside of the vapor deposition chamber 10 is maintained at a high vacuum, the branch pipe section 14 is heated to a temperature at which the metal halogen/compound 16 sublimates (for example, TnBr is used). (approximately 460° C.) to sublimate the metal halide compound 16, and at the same time heat the inner wall of the straight pipe portion 12 with the heater 18. At this time, in order to prevent the sublimated metal halide compound 16 from being discharged outside the system, the pipe 2
The figure 8 part 28 of 6 is cooled with cooling water to capture the sublimated metal halide compound.

次に、金属ハロゲン化合物１６がある程度昇華した時点
において、コック３４を閉じ、蒸着室１゜の内壁面に金
属ハロゲン化合物１６を蒸着させる。Next, when the metal halide compound 16 has sublimated to some extent, the cock 34 is closed and the metal halide compound 16 is vapor deposited on the inner wall surface of the vapor deposition chamber 1°.

その後、蒸着室ｌＯ内を室温まで冷却し、蒸着室１０と
パイプ２６との接続を解除し、支持具２ｏ、２２間にフ
ァイバ２４を張設し、固定する。そして、再び蒸着室ｌ
Ｏをパイプ２６に接続し、蒸着室ｌＯ内を高真空にする
。蒸着室が高真空になった時点において、蒸着室１０内
にアルゴンガス等の不活性ガスを流入させ、コック３４
を閉じ、蒸着室ｌＯ内をヒータ１８．１９により蒸着に
適した温度に昇温し、ファイバ２４に金属ハロゲン化合
物１６を蒸着、拡散させる。なお、ファイバ２４がＴｊ
Ｂｒ　−Ｔｊ工　　であるときは、金属ハロゲン化合物
１６として、高純度のＴｊＢｒを用いることが望ましく
、ファイバ２４がＡｌｌＣｌ　−ＡＪＢｌ−のときは、
金属ハロゲン化合物１６としてＡｌｌＣｌを用いること
が望ましい。Thereafter, the inside of the vapor deposition chamber 1O is cooled to room temperature, the connection between the vapor deposition chamber 10 and the pipe 26 is released, and the fiber 24 is stretched and fixed between the supports 2o and 22. Then, the deposition chamber l
O is connected to the pipe 26, and the inside of the vapor deposition chamber lO is made into a high vacuum. When the vapor deposition chamber becomes a high vacuum, an inert gas such as argon gas is flowed into the vapor deposition chamber 10, and the cock 34 is turned on.
is closed, and the temperature in the vapor deposition chamber IO is raised to a temperature suitable for vapor deposition using heaters 18 and 19, and the metal halide compound 16 is vapor-deposited and diffused into the fiber 24. Note that the fiber 24 is Tj
When the fiber 24 is AllCl-AJBl-, it is desirable to use high-purity TjBr as the metal halide compound 16, and when the fiber 24 is AllCl-AJBl-,
It is desirable to use AllCl as the metal halide compound 16.

上記のファイバ２４への金属ハロゲン化合物１６の一様
な蒸着、拡散速度、拡散厚さ等は、蒸着室ｌＯ内の雰囲
気、温度勾配（蒸着室１０内の昇温速度）等の条件によ
り定まる。The uniform vapor deposition, diffusion rate, diffusion thickness, etc. of the metal halide compound 16 onto the fiber 24 are determined by conditions such as the atmosphere in the vapor deposition chamber 1O and the temperature gradient (temperature increase rate in the vapor deposition chamber 10).

上記の如くファイバ２４に金属ハロゲン化合物１６を蒸
着、拡散させることにより、中心部のコアの周囲に組成
比が漸５次変化しているクラッド部を形成することがで
き、グレイテッドインデックス型の光ファイバを得るこ
とができる。そして、コアの周囲にクラッド層を形成す
ることにより、ファイバの側面における損失を低減させ
、端面における光の発散を小さくでき、集光性が向上す
る。By vapor depositing and diffusing the metal halide compound 16 on the fiber 24 as described above, it is possible to form a cladding portion in which the composition ratio gradually changes five orders of magnitude around the central core, and a graded index type light beam can be formed. fiber can be obtained. By forming a cladding layer around the core, loss at the side surfaces of the fiber can be reduced, light divergence at the end face can be reduced, and light convergence can be improved.

なお、前記実施例においては、ファイバ２４に金属ハロ
ゲン化合物を蒸着、拡散させる場合について説明したが
、金属ハロゲン化合物１６に代えてファイバ２４とは異
なる組成を有する金属ハ胃ゲン化合物混晶体を用いても
よい。In the above embodiment, a case was explained in which a metal halide compound was vapor-deposited and diffused into the fiber 24, but instead of the metal halide compound 16, a metal halide compound mixed crystal having a composition different from that of the fiber 24 was used. Good too.

〔発明の効果〕〔Effect of the invention〕

以上説明したように、本発明によれば、グレイテッドイ
ンデックス型の金属ハロゲン化合物混晶体光ファイバを
得ることができる。As explained above, according to the present invention, a graded index metal halide compound mixed crystal optical fiber can be obtained.

【図面の簡単な説明】[Brief explanation of the drawing]

図は本発明に係る金属ハロゲン化合物混晶体光ファイバ
の製造に用いる装置の一例を示す模式図である。 １０・・・蒸着室、The figure is a schematic diagram showing an example of an apparatus used for manufacturing a metal halide compound mixed crystal optical fiber according to the present invention. 10... Vapor deposition chamber,

Claims (1)

【特許請求の範囲】[Claims] 繊維状の金属ハロゲン化合物混晶体の表面に、金属ハロ
ゲン化合物または前記混晶体とは異なる組成比を有する
金属ハロゲン化合物混晶体を蒸着、拡散し、前記繊維状
の金属ハロゲン化合物混晶体の表層部に中心部とは屈折
率の異なるクラッド層を形成することを特徴とする金属
ハロゲン化合物混晶体光ファイバの製造方法。A metal halide compound or a metal halide compound mixed crystal having a composition ratio different from that of the metal halide compound is vapor-deposited and diffused onto the surface of the fibrous metal halide compound mixed crystal, and the metal halide compound mixed crystal having a composition ratio different from that of the metal halide compound mixed crystal is vapor-deposited and diffused on the surface of the fibrous metal halide compound mixed crystal. A method for manufacturing a metal halide compound mixed crystal optical fiber, comprising forming a cladding layer having a refractive index different from that of the central portion.
JP59142034A 1984-07-09 1984-07-09 Production of optical fiber consisting of mixed crystal material of metallic halide compound Pending JPS6120908A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP59142034A JPS6120908A (en) 1984-07-09 1984-07-09 Production of optical fiber consisting of mixed crystal material of metallic halide compound

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP59142034A JPS6120908A (en) 1984-07-09 1984-07-09 Production of optical fiber consisting of mixed crystal material of metallic halide compound

Publications (1)

Publication Number Publication Date
JPS6120908A true JPS6120908A (en) 1986-01-29

Family

ID=15305824

Family Applications (1)

Application Number Title Priority Date Filing Date
JP59142034A Pending JPS6120908A (en) 1984-07-09 1984-07-09 Production of optical fiber consisting of mixed crystal material of metallic halide compound

Country Status (1)

Country Link
JP (1) JPS6120908A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH01281407A (en) * 1988-05-09 1989-11-13 Nippon Telegr & Teleph Corp <Ntt> Method and apparatus for producing single crystal fiber
AU603459B2 (en) * 1987-06-25 1990-11-15 International Metals Reclamation Company, Inc., The Process for the detoxification of steel plant wastes
US5560759A (en) * 1994-11-14 1996-10-01 Lucent Technologies Inc. Core insertion method for making optical fiber preforms and optical fibers fabricated therefrom
CN103983435A (en) * 2014-05-30 2014-08-13 香港理工大学深圳研究院 Micro-nano optical fiber micro experiment structure, manufacturing method thereof and measuring instrument

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS57116304A (en) * 1981-01-12 1982-07-20 Sumitomo Electric Ind Ltd Optical fiber for infrared and its production
JPS57151902A (en) * 1981-02-11 1982-09-20 Int Standard Electric Corp Optical fiber

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS57116304A (en) * 1981-01-12 1982-07-20 Sumitomo Electric Ind Ltd Optical fiber for infrared and its production
JPS57151902A (en) * 1981-02-11 1982-09-20 Int Standard Electric Corp Optical fiber

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU603459B2 (en) * 1987-06-25 1990-11-15 International Metals Reclamation Company, Inc., The Process for the detoxification of steel plant wastes
JPH01281407A (en) * 1988-05-09 1989-11-13 Nippon Telegr & Teleph Corp <Ntt> Method and apparatus for producing single crystal fiber
US5560759A (en) * 1994-11-14 1996-10-01 Lucent Technologies Inc. Core insertion method for making optical fiber preforms and optical fibers fabricated therefrom
CN103983435A (en) * 2014-05-30 2014-08-13 香港理工大学深圳研究院 Micro-nano optical fiber micro experiment structure, manufacturing method thereof and measuring instrument

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