JPH0137339B2 - - Google Patents
Info
- Publication number
- JPH0137339B2 JPH0137339B2 JP56058626A JP5862681A JPH0137339B2 JP H0137339 B2 JPH0137339 B2 JP H0137339B2 JP 56058626 A JP56058626 A JP 56058626A JP 5862681 A JP5862681 A JP 5862681A JP H0137339 B2 JPH0137339 B2 JP H0137339B2
- Authority
- JP
- Japan
- Prior art keywords
- optical element
- optical
- infrared
- glass
- fluoride
- 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
Links
- 230000003287 optical effect Effects 0.000 claims description 64
- 238000004519 manufacturing process Methods 0.000 claims description 18
- 238000000034 method Methods 0.000 claims description 10
- 239000005383 fluoride glass Substances 0.000 claims description 9
- 239000000075 oxide glass Substances 0.000 claims description 9
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical group F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 claims description 2
- 230000005540 biological transmission Effects 0.000 claims 1
- 239000011521 glass Substances 0.000 description 8
- 229910017855 NH 4 F Inorganic materials 0.000 description 6
- 239000007789 gas Substances 0.000 description 6
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 5
- 229910052782 aluminium Inorganic materials 0.000 description 5
- 238000006243 chemical reaction Methods 0.000 description 5
- 239000011347 resin Substances 0.000 description 5
- 229920005989 resin Polymers 0.000 description 5
- 230000000873 masking effect Effects 0.000 description 4
- KRHYYFGTRYWZRS-UHFFFAOYSA-M Fluoride anion Chemical compound [F-] KRHYYFGTRYWZRS-UHFFFAOYSA-M 0.000 description 3
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 description 3
- 238000004891 communication Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 229910052731 fluorine Inorganic materials 0.000 description 3
- 239000011737 fluorine Substances 0.000 description 3
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 2
- 229910004298 SiO 2 Inorganic materials 0.000 description 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 229910052814 silicon oxide Inorganic materials 0.000 description 2
- 239000000758 substrate Substances 0.000 description 2
- 239000002912 waste gas Substances 0.000 description 2
- 229910016036 BaF 2 Inorganic materials 0.000 description 1
- 229910004261 CaF 2 Inorganic materials 0.000 description 1
- 229910005690 GdF 3 Inorganic materials 0.000 description 1
- 238000000137 annealing Methods 0.000 description 1
- WUKWITHWXAAZEY-UHFFFAOYSA-L calcium difluoride Chemical compound [F-].[F-].[Ca+2] WUKWITHWXAAZEY-UHFFFAOYSA-L 0.000 description 1
- 229910001634 calcium fluoride Inorganic materials 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000002425 crystallisation Methods 0.000 description 1
- 230000008025 crystallization Effects 0.000 description 1
- 238000003682 fluorination reaction Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000013307 optical fiber Substances 0.000 description 1
- 238000001259 photo etching Methods 0.000 description 1
- 238000004544 sputter deposition Methods 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 238000005979 thermal decomposition reaction Methods 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
Landscapes
- Optical Integrated Circuits (AREA)
- Optical Fibers, Optical Fiber Cores, And Optical Fiber Bundles (AREA)
- Surface Treatment Of Glass (AREA)
- Glass Compositions (AREA)
Description
【発明の詳細な説明】
本発明は0.3〜8μmの紫外〜赤外の領域の波長
で用いることができる赤外用光学素子の製造方法
に関するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing an infrared optical element that can be used at wavelengths in the ultraviolet to infrared region of 0.3 to 8 μm.
従来の光学素子は酸化ケイ素系（SiO2）ガラ
スを主構成素材としているが、このガラス素材は
Si―Ｏの結合の振動に起因する赤外吸収を有する
ため、光学素子としては0.3〜2μmの紫外〜近赤
外域用に限られ、それより長波長の波長領域にお
いては利用することができなかつた。 Conventional optical elements are mainly composed of silicon oxide (SiO 2 ) glass, but this glass material
Since it has infrared absorption caused by the vibration of the Si--O bond, its use as an optical element is limited to the ultraviolet to near-infrared region of 0.3 to 2 μm, and it cannot be used in the longer wavelength region. Ta.
一方、先行技術によればレイリー散乱は波長の
４乗に逆比例して低減するので酸化ケイ素に比べ
て赤外吸収端が長波長側に位置するフツ化物ガラ
ス等のガラス素材で光フアイバを構成し、赤外線
の光通信を行なうことにより、一層低損失で中継
間隔の長い通信が実現できる。このような点か
ら、従来の酸化物ガラスでは不可能な2μm以上の
長波長の赤外線で使用可能な光学素子の製造方法
の出現が要望されている。 On the other hand, according to the prior art, Rayleigh scattering is reduced in inverse proportion to the fourth power of the wavelength, so optical fibers are made of glass materials such as fluoride glass whose infrared absorption edge is located on the longer wavelength side compared to silicon oxide. However, by using infrared optical communication, communication with even lower loss and longer relay intervals can be realized. From this point of view, there is a demand for a method for manufacturing optical elements that can be used with infrared rays of long wavelengths of 2 μm or more, which is impossible with conventional oxide glasses.
従来の酸化物ガラスを用いた光学素子の製造方
法では、フツ化物ガラスが極めて結晶化しやすく
不安定なものであるために、赤外線で使用可能な
フツ化物の光学素子は製造不可能である。 With conventional methods for manufacturing optical elements using oxide glass, it is impossible to manufacture fluoride optical elements that can be used in infrared rays because fluoride glass is extremely susceptible to crystallization and is unstable.
また、フツ化物の光学素子はCaF2結晶のレン
ズ等が知られているが、大きなものの作製や量産
には適していない。しかもフツ化物ガラスを用い
た光学素子の製造方法については特に紹介されて
いない状況にある。 In addition, although fluoride optical elements such as CaF 2 crystal lenses are known, they are not suitable for fabrication of large items or mass production. Furthermore, there is no particular introduction to a method for manufacturing optical elements using fluoride glass.
本発明は前記現状に鑑みてなされたもので、そ
の目的は先行技術の欠点を解決して波長0.3〜
8μmの紫外〜赤外領域で使用可能な赤外用光学素
子の製造方法を提供することにある。 The present invention has been made in view of the above-mentioned current situation, and its purpose is to solve the drawbacks of the prior art and to
The object of the present invention is to provide a method for manufacturing an infrared optical element that can be used in the ultraviolet to infrared region of 8 μm.
前記目的を達成する本発明の赤外用光学素子の
製造方法は、酸化物のガラスより構成された光学
素子をF2，HF，NH4FあるいはNH4F・HFの雰
囲気下で100％フツ素化してフツ化物ガラスより
構成された光学素子を製造することを特徴として
いる。 The method of manufacturing an infrared optical element of the present invention which achieves the above object is to process an optical element made of oxide glass in an atmosphere of F 2 , HF, NH 4 F or NH 4 F/HF. The method is characterized in that it manufactures an optical element made of fluoride glass.
本発明で実現できる光学素子としては、光集積
回路用の光導波路、レンズ、フイルタ等がある。 Optical elements that can be realized by the present invention include optical waveguides, lenses, filters, etc. for optical integrated circuits.
本発明による赤外用光学素子の製造方法は、基
本的には酸化物のガラスより構成された光導波路
変調器、フイルタ等の光学素子を、F2，HF，
NH4FあるいはNH4F・HFの雰囲気下で100％フ
ツ素化を促進し、必要に応じて再加熱してフツ化
物の部分を溶融してガラス化し、酸化物で構成さ
れていた構造をそのままフツ化物ガラスで置き換
え、2μm〜8μmの赤外域の波長でも用いることが
できる赤外用光学素子を製造するものである。 The method for manufacturing an infrared optical element according to the present invention basically includes optical elements such as optical waveguide modulators and filters made of oxide glass.
Promote 100% fluorination in an atmosphere of NH 4 F or NH 4 F/HF, reheat as necessary to melt and vitrify the fluoride part, and change the structure composed of oxides. The purpose is to manufacture an infrared optical element that can be used at wavelengths in the infrared region of 2 μm to 8 μm by directly replacing it with fluoride glass.
本発明によつて得られるフツ化物の光学素子に
は比較的自由な構造を設けることができる。即
ち、酸化物ガラスよりなる光学素子を出発材料と
しているため、ホトエツチング法や逆スパツタ法
等で形成された複雑な回路をそのままフツ素化し
て、赤外線で使用可能な光学素子を得ることがで
きるのである。 The fluoride optical element obtained by the present invention can be provided with a relatively free structure. In other words, since an optical element made of oxide glass is used as a starting material, a complex circuit formed by photoetching or inverse sputtering can be directly fluorinated to obtain an optical element that can be used in infrared rays. be.
以下本発明を実施例によつて詳細に説明する
が、本発明はこれによりなんら限定されるもので
はない。 EXAMPLES The present invention will be explained in detail below with reference to Examples, but the present invention is not limited thereto in any way.
実施例 １
第１図は本発明の製造方法を実施するための装
置の一構成例を示す模式図である。図において、
１は本発明を適用する光学素子であり、ここでは
光分岐回路を例にとり、理解しやすいように拡大
して示してある。その断面構造は第２図に示した
ようになつている。２は例えばZrO2（25.2モル％）
―BaO（13.2モル％）―Gd2O3（1.6モル％）―
B2O3（12.0モル％）―SiO2（48.0モル％）よりなる
ガラス薄膜で形成された光導波路部、３は例えば
CaF2で形成された基板である。４はフツ素樹脂
を内側に被覆したガラス容器あるいはアルミニウ
ム製の容器（反応系）であり、内部に上記光学素
子１が設置される。５はF2ボンベ、６は減圧バ
ルブ、７はフツ素樹脂チユーブあるいはアルミニ
ウム製チユーブ、８は廃気用パイプ、９はガス洗
浄器である。次に製造方法を説明する。Example 1 FIG. 1 is a schematic diagram showing an example of the configuration of an apparatus for carrying out the manufacturing method of the present invention. In the figure,
Reference numeral 1 denotes an optical element to which the present invention is applied, and here an optical branch circuit is taken as an example and shown enlarged for ease of understanding. Its cross-sectional structure is as shown in FIG. 2 is, for example, ZrO 2 (25.2 mol%)
-BaO (13.2 mol%) -Gd 2 O 3 (1.6 mol%) -
The optical waveguide section 3 is made of a glass thin film made of B 2 O 3 (12.0 mol%) - SiO 2 (48.0 mol%), for example.
The substrate is made of CaF2 . Reference numeral 4 denotes a glass container or aluminum container (reaction system) coated with fluorine resin on the inside, in which the optical element 1 is installed. 5 is an F2 cylinder, 6 is a pressure reducing valve, 7 is a fluororesin tube or aluminum tube, 8 is a waste gas pipe, and 9 is a gas scrubber. Next, the manufacturing method will be explained.
F2ボンベ５より減圧バルブ６によつて流量調
整しながらフツ素樹脂チユーブあるいはアルミニ
ウム製チユーブ７を通じて容器（反応系）４内に
F2を導入し、４時間かけて光学素子１の酸化物
ガラスより形成された光導波路部２を100％フツ
素化した。このときに廃気用パイプ８を通じてガ
ス洗浄器９で未反応ガスをトラツプした。 F2 is fed into the container (reaction system) 4 from the cylinder 5 through the fluororesin tube or aluminum tube 7 while adjusting the flow rate with the pressure reducing valve 6.
F 2 was introduced, and the optical waveguide portion 2 formed of the oxide glass of the optical element 1 was 100% fluorinated over a period of 4 hours. At this time, unreacted gas was trapped in a gas washer 9 through a waste gas pipe 8.
次いで、フツ素化した光学素子（光分岐回路）
１を取り出し、600℃に加熱してフツ素化した光
導波路部２をガラス化し、後にアニールした。 Next, a fluorinated optical element (optical branch circuit)
1 was taken out and heated to 600° C. to vitrify the fluorinated optical waveguide portion 2, which was then annealed.
このようにして得られた光分岐回路は、光導波
路部２がSiF4とBF3の気化したZrF4―BaF2―
GdF3ガラスで形成されているため、0.3〜8μmの
光を導波し、酸化物系光分岐回路では不可能な２
〜8μmの赤外光用分岐回路として用いることがで
きる。 In the optical branch circuit obtained in this way, the optical waveguide portion 2 is made of ZrF 4 -BaF 2 - which is vaporized SiF 4 and BF 3 .
Since it is made of GdF 3 glass, it can guide light of 0.3 to 8 μm, which is impossible with oxide-based optical branch circuits.
Can be used as a branch circuit for ~8μm infrared light.
実施例 ２
第３図は本実施例で用いた光学素子（分波器）
の平面図である。第１，２図で示した光分岐回路
と同一構成の素子の表面の１０の斜線部（以下マ
スキング部位と言う）を樹脂でマスキングして、
実施例―１の場合と同様第１図に示す反応系内に
設置する。第１図における５のF2ボンベをHF5ボ
ンベに置き換え、ガラス容器（反応系）４内で10
時間かけてマスキング部位１０以外の光導波路部
２を100％フツ素化した。次いで、アセトンで樹
脂を洗い流し、600℃に加熱してフツ素化された
（マスキング部位10以外の部分）光導波路部をガ
ラス化し、後にアニールした。Example 2 Figure 3 shows the optical element (brancher) used in this example.
FIG. Ten diagonally shaded areas (hereinafter referred to as masking areas) on the surface of an element having the same configuration as the optical branch circuit shown in FIGS. 1 and 2 are masked with resin,
As in the case of Example-1, it is installed in the reaction system shown in FIG. Replace the 5 F 2 cylinders in Figure 1 with HF 5 cylinders, and place 10 in the glass container (reaction system) 4.
The optical waveguide portion 2 other than the masking portion 10 was 100% fluorinated over time. Next, the resin was washed away with acetone, and the fluorinated optical waveguide section (other than the masking section 10) was vitrified by heating to 600.degree. C., followed by annealing.
このようにして得られた光学素子は、分岐回路
の中にフツ化物ガラスと酸化物ガラスで区別され
て構成された光導波路を有し、0.3〜3μmと３〜
8μmでの波長をより分けられる光分波器に変換さ
れたことがわかる。 The optical element obtained in this way has optical waveguides configured with fluoride glass and oxide glass in the branch circuit, and has optical waveguides of 0.3 to 3 μm and 3 to 3 μm.
It can be seen that it has been converted into an optical demultiplexer that can separate wavelengths at 8 μm.
なお、本実施例ではHFガスのソースとして、
NH4FやNH4F・HFの熱分解を利用しても同様
の結果が得られた。 In addition, in this example, as a source of HF gas,
Similar results were obtained using thermal decomposition of NH 4 F and NH 4 F/HF.
以上説明したように、本発明の赤外用光学素子
の製造方法によると、微細な加工の難しいフツ化
物ガラスより構成された光学素子を、酸化物ガラ
ス製の素子を出発光学素子として100％フツ素化
することにより、簡単に製造できる。またその際
に、出発光学素子の機能を２〜6μmという従来の
光学素子では不可能であつた赤外領域で実現で
き、あるいは出発光学素子の機能とは異種の機能
を持つ光学素子にも変換できる。このような技術
は赤外用の種々の光学素子、レンズ、フイルタ、
グレーテイング等の製造にも利用でき、赤外用光
通信の部品製造技術として利用できる利点があ
る。 As explained above, according to the method for manufacturing an infrared optical element of the present invention, an optical element made of fluoride glass, which is difficult to process finely, can be manufactured using 100% fluoride glass using an element made of oxide glass as the starting optical element. It can be easily manufactured by In addition, in this case, the function of the starting optical element can be realized in the infrared region of 2 to 6 μm, which is impossible with conventional optical elements, or it can be converted into an optical element with a different function from that of the starting optical element. can. This technology uses various infrared optical elements, lenses, filters,
It can also be used to manufacture gratings, etc., and has the advantage of being used as a component manufacturing technology for infrared optical communications.
第１図は本発明の製造方法を実施するための装
置の構成を示す模式図、第２図は光学素子の断面
構造図、第３図は本発明の実施例で用いた光学素
子の平面図である。
１…光学素子、２…光導波路部、３…基板、４
…フツ素樹脂被覆ガラス容器あるいはアルミニウ
ム製容器（反応系）、５…F2ボンベ、６…減圧バ
ルブ、７…フツ素樹脂チユーブあるいはアルミニ
ウム製チユーブ、８…廃気用パイプ、９…ガス洗
浄器、１０…マスキング部位。
Fig. 1 is a schematic diagram showing the configuration of an apparatus for carrying out the manufacturing method of the present invention, Fig. 2 is a cross-sectional structural diagram of an optical element, and Fig. 3 is a plan view of an optical element used in an example of the present invention. It is. DESCRIPTION OF SYMBOLS 1... Optical element, 2... Optical waveguide part, 3... Substrate, 4
...Fluorine resin coated glass container or aluminum container (reaction system), 5... F2 cylinder, 6...Reducing valve, 7...Fluorine resin tube or aluminum tube, 8...Exhaust gas pipe, 9...Gas scrubber , 10...Masking site.
Claims (1)
子をF2またはHFの雰囲気下でフツ素化し、ある
いは光学素子上に酸化物の部分とフツ化物の部分
とが領域を分けて共存するように部分的にフツ素
化して、出発光学素子と同種機能を保持しながら
光の透過波長域を長波長域に拡張し、あるいは酸
化物ガラス導波路部分とフツ化物ガラス導波路部
分との共存により二波長の光を分波できるよう
な、出発光学素子とは異種の機能をもつ光学素子
を形成することを特徴とする赤外用光学素子の製
造方法。1. Optical elements such as optical waveguide circuits made of oxides are fluorinated in an F2 or HF atmosphere, or fluorinated so that oxide parts and fluoride parts coexist in separate areas on the optical element. By partially fluorinating the optical element to extend the light transmission wavelength range to a longer wavelength range while retaining the same function as the starting optical element, or by coexisting the oxide glass waveguide part and the fluoride glass waveguide part. A method for manufacturing an infrared optical element, which comprises forming an optical element having a function different from that of a starting optical element, which is capable of splitting light of two wavelengths.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP56058626A JPS57175748A (en) | 1981-04-20 | 1981-04-20 | Preparation of infrared optical element |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP56058626A JPS57175748A (en) | 1981-04-20 | 1981-04-20 | Preparation of infrared optical element |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS57175748A JPS57175748A (en) | 1982-10-28 |
| JPH0137339B2 true JPH0137339B2 (en) | 1989-08-07 |
Family
ID=13089783
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP56058626A Granted JPS57175748A (en) | 1981-04-20 | 1981-04-20 | Preparation of infrared optical element |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS57175748A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| IT1195179B (en) * | 1986-09-25 | 1988-10-12 | Cselt Centro Studi Lab Telecom | PROCEDURE FOR THE MANUFACTURE OF OPTICAL GUIDES FOR MEDIUM INFRARED |
| JPH02253205A (en) * | 1989-03-28 | 1990-10-12 | Sumitomo Electric Ind Ltd | Optical circuit |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS52101223A (en) * | 1976-02-20 | 1977-08-25 | Sumitomo Electric Industries | Process for preparing glass product |
| JPS52139447A (en) * | 1976-05-17 | 1977-11-21 | Sumitomo Electric Ind Ltd | Preparation of optical glass fiber |
| JPS5357846A (en) * | 1976-11-05 | 1978-05-25 | Mitsubishi Metal Corp | Method of manufacturing light transmitting material |
| JPS54131044A (en) * | 1978-04-04 | 1979-10-11 | Nippon Telegr & Teleph Corp <Ntt> | Production of parent material for optical communication fiber |
| JPS5567533A (en) * | 1978-11-07 | 1980-05-21 | Nippon Telegr & Teleph Corp <Ntt> | Production of glass base material for light transmission |
-
1981
- 1981-04-20 JP JP56058626A patent/JPS57175748A/en active Granted
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS52101223A (en) * | 1976-02-20 | 1977-08-25 | Sumitomo Electric Industries | Process for preparing glass product |
| JPS52139447A (en) * | 1976-05-17 | 1977-11-21 | Sumitomo Electric Ind Ltd | Preparation of optical glass fiber |
| JPS5357846A (en) * | 1976-11-05 | 1978-05-25 | Mitsubishi Metal Corp | Method of manufacturing light transmitting material |
| JPS54131044A (en) * | 1978-04-04 | 1979-10-11 | Nippon Telegr & Teleph Corp <Ntt> | Production of parent material for optical communication fiber |
| JPS5567533A (en) * | 1978-11-07 | 1980-05-21 | Nippon Telegr & Teleph Corp <Ntt> | Production of glass base material for light transmission |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS57175748A (en) | 1982-10-28 |
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