JPH0727935A - Optical waveguide type polarizer - Google Patents
Optical waveguide type polarizerInfo
- Publication number
- JPH0727935A JPH0727935A JP17171193A JP17171193A JPH0727935A JP H0727935 A JPH0727935 A JP H0727935A JP 17171193 A JP17171193 A JP 17171193A JP 17171193 A JP17171193 A JP 17171193A JP H0727935 A JPH0727935 A JP H0727935A
- Authority
- JP
- Japan
- Prior art keywords
- optical waveguide
- polarizer
- type optical
- thin film
- type
- 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
Landscapes
- Optical Integrated Circuits (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、光計測、光通信等の光
集積回路に用いられる光導波路型偏光子に関するもので
ある。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical waveguide type polarizer used for an optical integrated circuit such as optical measurement and optical communication.
【０００２】[0002]
【従来の技術】ニオブ酸リチウム（ＬｉＮｂＯ3 ）結晶
基板を用いた光導波路型偏光子には、Ｔｉ（チタン）拡
散型光導波路の表面上に金属薄膜を装荷した構成の偏光
子（金属膜装荷型）や、ＸカットあるいはＺカットのニ
オブ酸リチウム結晶基板にプロトン交換型光導波路を形
成した構成の偏光子（プロトン交換型）がある。2. Description of the Related Art An optical waveguide type polarizer using a lithium niobate (LiNbO 3 ) crystal substrate has a structure in which a metal thin film is loaded on the surface of a Ti (titanium) diffusion type optical waveguide (metal film loading). Type) and a polarizer (proton exchange type) having a structure in which a proton exchange type optical waveguide is formed on an X-cut or Z-cut lithium niobate crystal substrate.
【０００３】[0003]
【発明が解決しようとする課題】金属膜装荷型偏光子
は、ＴＭモード偏光成分が金属薄膜内の自由電子を励振
し、ＴＥモード偏光成分に比べて大きく減衰する現象を
利用している。この金属膜装荷型偏光子は、Ｔｉ拡散型
光導波路に使用でき、低損失で、かつ低駆動電圧特性を
有する光集積回路が実現できる。しかし、高い消光比が
得難いという欠点がある。一方、プロトン交換型偏光子
は、結晶基板の光学的方向を考慮することにより、光導
波路自体にＴＥモード偏光成分あるいはＴＭモード偏光
成分のみを導波する偏光子機能を持たせたものである。
プロトン交換型偏光子は高い消光比が得られるが、プロ
トン交換型偏光子を用いた光集積回路では、低駆動電圧
特性が得られないという欠点がある。The metal film loaded type polarizer utilizes a phenomenon in which a TM mode polarization component excites free electrons in the metal thin film and is largely attenuated as compared with the TE mode polarization component. This metal film loaded type polarizer can be used for a Ti diffusion type optical waveguide, and an optical integrated circuit having low loss and low driving voltage characteristics can be realized. However, there is a drawback that it is difficult to obtain a high extinction ratio. On the other hand, in the proton exchange type polarizer, the optical waveguide itself has a polarizer function of guiding only the TE mode polarization component or the TM mode polarization component in consideration of the optical direction of the crystal substrate.
The proton exchange type polarizer can obtain a high extinction ratio, but an optical integrated circuit using the proton exchange type polarizer has a drawback that low driving voltage characteristics cannot be obtained.
【０００４】金属膜装荷型やプロトン交換型の光導波路
型偏光子に関する上記の問題を解決するものとして、変
調器部分としてのＴｉ拡散型光導波路と、偏光子部分と
してのプロトン交換型光導波路とを、同一結晶基板上で
接合して構成した光集積回路が考えられている。しか
し、このような複合型の光集積回路では、プロトン交換
型光導波路の偏光子部分で放射された不要な偏光成分が
迷光となり、短い偏光子長では高い消光比を得ることが
できない。As a solution to the above-mentioned problems relating to a metal film loaded type or a proton exchange type optical waveguide type polarizer, a Ti diffusion type optical waveguide as a modulator portion and a proton exchange type optical waveguide as a polarizer portion are provided. An optical integrated circuit configured by bonding the above on the same crystal substrate is considered. However, in such a composite type optical integrated circuit, an unnecessary polarization component emitted in the polarizer portion of the proton exchange type optical waveguide becomes stray light, and a high extinction ratio cannot be obtained with a short polarizer length.
【０００５】本発明は、上述の事情に鑑みてなされたも
のであり、消光比が高く、かつ低駆動電圧特性が得ら
れ、しかも光集積回路素子が小型化できる光導波路型偏
光子を提供することを目的としている。The present invention has been made in view of the above circumstances, and provides an optical waveguide type polarizer having a high extinction ratio, a low driving voltage characteristic, and a miniaturized optical integrated circuit element. Is intended.
【０００６】[0006]
【課題を解決するための手段】本発明の光導波路型偏光
子は、ニオブ酸リチウムの単結晶基板上に、Ｔｉ拡散型
光導波路とプロトン交換型光導波路とを直列に接合して
配置し、このＴｉ拡散型光導波路の表面上に誘電体膜と
金属薄膜とを順次形成したことを特徴としている。上述
に加えて本発明の光導波路型偏光子は、Ｔｉ拡散型光導
波路の表面上に形成する誘電体膜が窒化ケイ素膜である
こと、及びＴｉ拡散型光導波路の表面上に形成する金属
薄膜がアルミニウム薄膜であることを特徴としている。The optical waveguide type polarizer of the present invention comprises a Ti diffusion type optical waveguide and a proton exchange type optical waveguide which are bonded in series on a single crystal substrate of lithium niobate. A feature is that a dielectric film and a metal thin film are sequentially formed on the surface of this Ti diffusion type optical waveguide. In addition to the above, in the optical waveguide type polarizer of the present invention, the dielectric film formed on the surface of the Ti diffusion type optical waveguide is a silicon nitride film, and the metal thin film formed on the surface of the Ti diffusion type optical waveguide. Is an aluminum thin film.
【０００７】[0007]
【作用】図１は、本発明に係る光導波路型偏光子の基本
的構造を示す斜視図である。図中、１は単結晶基板、２
は単結晶基板１上に配置されたＴｉ拡散型光導波路、３
はＴｉ拡散型光導波路２に直列に接合して単結晶基板１
上に配置されたプロトン交換型光導波路、４はＴｉ拡散
型光導波路２の表面上に形成した誘電体膜、５は誘電体
膜４の表面上に形成した金属薄膜、６は入射光、７は出
射光である。1 is a perspective view showing the basic structure of an optical waveguide type polarizer according to the present invention. In the figure, 1 is a single crystal substrate, 2
Is a Ti diffusion type optical waveguide disposed on the single crystal substrate 1, 3
Is connected to the Ti diffusion type optical waveguide 2 in series and the single crystal substrate 1
The proton exchange type optical waveguide arranged above, 4 is a dielectric film formed on the surface of the Ti diffusion type optical waveguide 2, 5 is a metal thin film formed on the surface of the dielectric film 4, 6 is incident light, and 7 is Is the emitted light.
【０００８】単結晶基板１には、ニオブ酸リチウム、タ
ンタル酸リチウム（ＬｉＴａＯ3 ）等の従来より光導波
路に使用されている単結晶を用いることができるが、製
造が容易で消光比の高い偏光子を得るには、ニオブ酸リ
チウムの使用が好ましい。Ｔｉ拡散型光導波路２は、フ
ォトマスクを用いて単結晶基板１上にチタンを所望のパ
ターンに蒸着し、次に高温の酸素雰囲気中でアニール
し、チタン原子を単結晶基板１中に拡散させる方法（熱
拡散法）で形成する。チタン原子が拡散した部分は、チ
タン原子が拡散していない部分に比べて屈折率が高いの
で、光導波路として機能する。The single crystal substrate 1 may be made of a single crystal such as lithium niobate or lithium tantalate (LiTaO 3 ) which has been used in optical waveguides, but it is easy to manufacture and has a high extinction ratio. The use of lithium niobate is preferred to obtain offspring. In the Ti diffusion type optical waveguide 2, titanium is vapor-deposited in a desired pattern on the single crystal substrate 1 using a photomask and then annealed in a high temperature oxygen atmosphere to diffuse titanium atoms into the single crystal substrate 1. It is formed by a method (heat diffusion method). The portion where the titanium atoms are diffused has a higher refractive index than the portion where the titanium atoms are not diffused, and thus functions as an optical waveguide.
【０００９】上述のように、金属薄膜５は、不要なＴＭ
偏波成分を吸収する働きを有する。金属元素であれば光
波を吸収するので、アルミニウム（Ａｌ），銀（Ａ
ｇ），銅（Ｃｕ），金（Ａｕ）等いずれの金属を用いて
もよいが、特にアルミニウムは、複素誘電率の虚部が大
きいので光波の吸収効率が高く、金属薄膜５の材料とし
て好適である。誘電体膜４は、上層の金属薄膜５がＴＭ
偏波成分を吸収する作用を促進し、吸収効率をより一層
高めることに寄与する。誘電体膜４の形成には、公知の
窒化ケイ素（Ｓｉ3 Ｎ4 ）や酸化ケイ素（ＳｉＯ2 ）等
が使用でき、金属薄膜５にアルミニウム（Ａｌ）を用い
た場合は、特に窒化ケイ素は効果が大きいので、望まし
い材料である。As described above, the metal thin film 5 is an unnecessary TM.
It has the function of absorbing polarized components. Since a metal element absorbs light waves, aluminum (Al), silver (A
g), copper (Cu), gold (Au), or any other metal may be used, but aluminum has a large imaginary part of the complex permittivity and thus has a high light wave absorption efficiency and is suitable as a material for the metal thin film 5. Is. In the dielectric film 4, the upper metal thin film 5 is TM
It promotes the action of absorbing the polarized component and contributes to further increase the absorption efficiency. Known silicon nitride (Si 3 N 4 ) or silicon oxide (SiO 2 ) can be used for forming the dielectric film 4, and when aluminum (Al) is used for the metal thin film 5, silicon nitride is particularly effective. Is a desirable material because of its large size.
【００１０】Ｔｉ拡散型光導波路２の表面の一部又は全
表面上に誘電体膜４及び金属薄膜５を形成して成る金属
膜装荷型偏光子８と、プロトン交換型光導波路（プロト
ン交換型偏光子）３とは、単結晶基板１上に直列に接合
して配置し、Ｔｉ拡散型光導波路２側に光波の入力ポー
ト、プロトン交換型光導波路３側に光波の出力ポートを
設ければ、ＴＭモード偏波除去のための偏光子が構成さ
れる。A metal film loaded polarizer 8 formed by forming a dielectric film 4 and a metal thin film 5 on a part or all of the surface of the Ti diffusion type optical waveguide 2 and a proton exchange type optical waveguide (proton exchange type). The polarizer 3 is arranged on the single crystal substrate 1 so as to be connected in series, and a light wave input port is provided on the Ti diffusion type optical waveguide 2 side and a light wave output port is provided on the proton exchange type optical waveguide 3 side. , TM mode polarization removal is configured.
【００１１】[0011]
【実施例】本発明実施例 図１に示した本発明の光導波路型偏光子を製造し、偏光
子長に対するＴＭモード偏光の消光比を評価した。単結
晶基板１は、Ｘカットで幅（Ｚ方向）６ｍｍ，長さ（Ｙ
方向）１０ｍｍ，厚さ（Ｘ方向）１ｍｍのニオブ酸リチ
ウム単結晶基板である。この単結晶基板上にフォトマス
クを用いて、結晶表面の幅方向（Ｚ方向）の中央で、金
属チタンを結晶端より長さ１ｍｍ，幅５μｍで蒸着し
た。次にこの単結晶基板を１０００℃，酸素雰囲気中で
７時間アニーリングして、金属チタン原子を単結晶基板
中に拡散させ、長さ１ｍｍのＴｉ拡散型光導波路２を形
成した。得られたＴｉ拡散型光導波路２は光波伝搬効率
が０．１ｄＢ／ｃｍであり、損失が小さいことが示され
た。EXAMPLES manufactured optical waveguide polarizer of the present invention the present invention shown in Embodiment FIG 1 to evaluate the extinction ratio of the TM mode polarization for the polarizer length. The single crystal substrate 1 has a width (Z direction) of 6 mm and a length (Y
Direction) 10 mm, thickness (X direction) 1 mm lithium niobate single crystal substrate. Using a photomask, metal titanium was vapor-deposited on the single crystal substrate at the center of the crystal surface in the width direction (Z direction) with a length of 1 mm from the crystal end and a width of 5 μm. Next, this single crystal substrate was annealed at 1000 ° C. in an oxygen atmosphere for 7 hours to diffuse metal titanium atoms into the single crystal substrate to form a Ti diffusion type optical waveguide 2 having a length of 1 mm. The obtained Ti diffusion type optical waveguide 2 had a light wave propagation efficiency of 0.1 dB / cm, and it was shown that the loss was small.
【００１２】次に、上述したＴｉ拡散型光導波路２に直
列に接合して結晶幅方向の中央に、プロトン交換法によ
り安息香酸中で幅５μｍ，長さ９ｍｍのマスクを用い、
プロトン交換型光導波路３を結晶他端まで形成した。更
にこの単結晶基板を３５０℃，酸素雰囲気中で３．５時
間アニーリングした。また、Ｔｉ拡散型光導波路２の表
面上に、窒化ケイ素（Ｓｉ3 Ｎ4 ）の誘電体膜４を厚さ
５５ｎｍ，更に誘電体膜４の上に、アルミニウムの金属
薄膜５を厚さ２００ｎｍに蒸着法で形成し、Ｔｉ拡散型
光導波路２を金属膜装荷型偏光子８に構成した。この結
果、一つの単結晶基板１上に、長さが１ｍｍの金属膜装
荷型偏光子８と長さが９ｍｍのプロトン交換型光導波路
（プロトン交換型偏光子）３とを直列に接合して構成し
た新規性を有する複合型偏光子を得た。Next, using a mask having a width of 5 μm and a length of 9 mm in benzoic acid by the proton exchange method, which was bonded in series to the Ti diffusion type optical waveguide 2 described above and was formed in the center in the crystal width direction,
The proton exchange type optical waveguide 3 was formed up to the other end of the crystal. Further, this single crystal substrate was annealed at 350 ° C. in an oxygen atmosphere for 3.5 hours. Further, a dielectric film 4 of silicon nitride (Si 3 N 4 ) having a thickness of 55 nm is formed on the surface of the Ti diffusion type optical waveguide 2, and a metal thin film 5 of aluminum having a thickness of 200 nm is further formed on the dielectric film 4. The Ti diffusion type optical waveguide 2 was formed by a vapor deposition method to form a metal film loaded type polarizer 8. As a result, a metal film loaded polarizer 8 having a length of 1 mm and a proton exchange optical waveguide (proton exchange polarizer) 3 having a length of 9 mm are bonded in series on one single crystal substrate 1. A composite polarizer having the constructed novelty was obtained.
【００１３】上述のように製造した偏光子のＴＭモード
偏光の消光比を測定した。導波光として波長０．８μｍ
の半導体レーザを用い、この半導体レーザから出射した
直線偏光の光波を、偏波保持ファイバを介してＴｉ拡散
型光導波路２側の入力ポートより偏光子に偏光消光比０
ｄＢ（ＴＭ／ＴＥ＝１）で入射した。偏光子のプロトン
交換型光導波路３側の出力ポートから出射した光波の強
度を、消光比６０ｄＢのいわゆるGlan-Thompson プリズ
ムを用いて測定した。次に、上述の測定に供試した偏光
子は、プロトン交換型光導波路３側の結晶端面を少しず
つ研磨して削ることにより、プロトン交換型光導波路３
の長さを０〜４．３ｍｍの範囲で順次短くした。このよ
うにして、長さ１ｍｍの金属膜装荷型偏光子８を含む複
合型偏光子の長さを短くしながら、適当な偏光子長にお
いて上述と同様な測定方法で、ＴＭモード偏光の消光比
を測定した。The extinction ratio of TM mode polarized light of the polarizer manufactured as described above was measured. Wavelength 0.8μm as guided light
Of the linearly polarized light wave emitted from this semiconductor laser to the polarizer from the input port on the side of the Ti diffusion type optical waveguide 2 through the polarization maintaining fiber to the polarization extinction ratio 0.
It was incident at dB (TM / TE = 1). The intensity of the light wave emitted from the output port of the polarizer on the side of the proton exchange type optical waveguide 3 was measured using a so-called Glan-Thompson prism having an extinction ratio of 60 dB. Next, the polarizer used in the above measurement was prepared by gradually polishing and scraping the crystal end surface on the side of the proton exchange type optical waveguide 3 to remove the proton exchange type optical waveguide 3
The length was shortened in the range of 0 to 4.3 mm. In this way, the extinction ratio of TM mode polarized light is measured by the same measurement method as above with an appropriate polarizer length while shortening the length of the composite polarizer including the metal film loaded polarizer 8 having a length of 1 mm. Was measured.
【００１４】従来例 誘電体膜４及び金属薄膜５を形成しなかったことを除
き、本発明実施例と同様の方法で従来例の複合型偏光子
を製造した。そして、本発明実施例におけると同一方法
により、偏光子長に対するＴＭモード偏光の消光比を測
定した。[0014] Except for not forming the conventional dielectric film 4 and the metal thin film 5, to produce a composite polarizer of prior art in the present invention embodiment similar manner. Then, the extinction ratio of the TM mode polarized light to the polarizer length was measured by the same method as in the embodiment of the present invention.
【００１５】図２は、本発明実施例と従来例とにおける
偏光子長に対するＴＭモード偏光の消光比の測定結果で
ある。偏光子として要求されるＴＭモード偏光の５０ｄ
Ｂ以上の消光比が、従来の偏光子と比べて本発明の偏光
子では、より短い偏光子長で得られることが分かり、従
来の複合型偏光子より小型な複合型偏光子ができること
が示されている。FIG. 2 shows the measurement results of the extinction ratio of TM mode polarized light with respect to the polarizer length in the embodiment of the present invention and the conventional example. 50d of TM mode polarized light required as a polarizer
It can be seen that an extinction ratio of B or more can be obtained with a shorter polarizer length in the polarizer of the present invention as compared with the conventional polarizer, which shows that a composite polarizer smaller than the conventional composite polarizer can be obtained. Has been done.
【００１６】[0016]
【発明の効果】以上説明したように本発明の光導波路型
偏光子は、金属膜装荷型偏光子とプロトン交換型光導波
路（プロトン交換型偏光子）を組み合わせ接合すること
で、高消光比、低駆動電圧特性という利点を有し、しか
も従来の複合型偏光子より小型化が可能である。As described above, the optical waveguide type polarizer of the present invention has a high extinction ratio by combining and bonding a metal film loaded type polarizer and a proton exchange type optical waveguide (proton exchange type polarizer). It has the advantage of low drive voltage characteristics and can be made smaller than conventional composite polarizers.
【図１】本発明による光導波路型偏光子の基本的構造を
示す斜視図である。FIG. 1 is a perspective view showing a basic structure of an optical waveguide type polarizer according to the present invention.
【図２】本発明及び従来の光導波路型偏光子における偏
光子長に対するＴＭモード偏光の消光比を示す測定図で
ある。FIG. 2 is a measurement diagram showing an extinction ratio of TM mode polarized light with respect to a polarizer length in the present invention and the conventional optical waveguide type polarizer.
１ 単結晶基板 ２ Ｔｉ拡散型光導波路 ３ プロトン交換型光導波路（プロトン交換型偏光
子） ４ 誘電体膜 ５ 金属薄膜 ６ 入射光 ７ 出射光 ８ 金属膜装荷型偏光子1 Single Crystal Substrate 2 Ti Diffused Optical Waveguide 3 Proton Exchange Optical Waveguide (Proton Exchange Polarizer) 4 Dielectric Film 5 Metal Thin Film 6 Incident Light 7 Exit Light 8 Metal Film Loaded Polarizer
Claims (3)
ｉ拡散型光導波路とプロトン交換型光導波路とを直列に
接合して配置し、上記Ｔｉ拡散型光導波路の表面上に誘
電体膜と金属薄膜とを順次形成したことを特徴とする光
導波路型偏光子。1. On a single crystal substrate of lithium niobate, T
An optical waveguide type characterized in that an i diffusion type optical waveguide and a proton exchange type optical waveguide are arranged so as to be joined in series, and a dielectric film and a metal thin film are sequentially formed on the surface of the Ti diffusion type optical waveguide. Polarizer.
誘電体膜が窒化ケイ素膜である請求項１に記載の光導波
路型偏光子。2. The optical waveguide type polarizer according to claim 1, wherein the dielectric film formed on the surface of the Ti diffusion type optical waveguide is a silicon nitride film.
金属薄膜がアルミニウム薄膜である請求項１又は請求項
２に記載の光導波路型偏光子。3. The optical waveguide type polarizer according to claim 1, wherein the metal thin film formed on the surface of the Ti diffusion type optical waveguide is an aluminum thin film.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP17171193A JPH0727935A (en) | 1993-07-12 | 1993-07-12 | Optical waveguide type polarizer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP17171193A JPH0727935A (en) | 1993-07-12 | 1993-07-12 | Optical waveguide type polarizer |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0727935A true JPH0727935A (en) | 1995-01-31 |
Family
ID=15928266
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP17171193A Pending JPH0727935A (en) | 1993-07-12 | 1993-07-12 | Optical waveguide type polarizer |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0727935A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007333756A (en) * | 2006-06-12 | 2007-12-27 | Fujitsu Ltd | Optical waveguide device and optical modulator |
| US7712829B2 (en) | 2004-11-30 | 2010-05-11 | Johnson Controls Technology Company | Seat structure for vehicle |
| CN113534334A (en) * | 2020-04-15 | 2021-10-22 | 格芯(美国)集成电路科技有限公司 | Stacked waveguide polarizer with conductive oxide strips |
| CN114486816A (en) * | 2022-01-20 | 2022-05-13 | 浙江大学嘉兴研究院 | Method for exciting surface plasmon resonance of nano cavity by optical waveguide |
| CN116430516A (en) * | 2023-04-21 | 2023-07-14 | 上海科技大学 | Optical polarizer |
-
1993
- 1993-07-12 JP JP17171193A patent/JPH0727935A/en active Pending
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7712829B2 (en) | 2004-11-30 | 2010-05-11 | Johnson Controls Technology Company | Seat structure for vehicle |
| JP2007333756A (en) * | 2006-06-12 | 2007-12-27 | Fujitsu Ltd | Optical waveguide device and optical modulator |
| CN113534334A (en) * | 2020-04-15 | 2021-10-22 | 格芯(美国)集成电路科技有限公司 | Stacked waveguide polarizer with conductive oxide strips |
| CN113534334B (en) * | 2020-04-15 | 2023-10-20 | 格芯(美国)集成电路科技有限公司 | Stacked waveguide polarizer with conductive oxide strips |
| CN114486816A (en) * | 2022-01-20 | 2022-05-13 | 浙江大学嘉兴研究院 | Method for exciting surface plasmon resonance of nano cavity by optical waveguide |
| CN114486816B (en) * | 2022-01-20 | 2023-10-13 | 浙江大学嘉兴研究院 | Method for exciting nano-cavity surface plasmon resonance by optical waveguide |
| CN116430516A (en) * | 2023-04-21 | 2023-07-14 | 上海科技大学 | Optical polarizer |
| CN116430516B (en) * | 2023-04-21 | 2024-03-08 | 上海科技大学 | Optical polarizer |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5546494A (en) | Optical waveguide device and manufacturing method of the same | |
| JPS60243606A (en) | Thin film optical element | |
| US4793675A (en) | Element having light waveguides and method of making same | |
| JPH0728007A (en) | Waveguide type optical device | |
| JPH0727935A (en) | Optical waveguide type polarizer | |
| JP3836950B2 (en) | Acousto-optic device | |
| JPH08286160A (en) | Acoustooptic filter | |
| US6233372B1 (en) | Waveguide path type polarization independent optical wavelength tunable filter | |
| JP2880770B2 (en) | Optical wavelength filter | |
| JP2581486B2 (en) | Optical waveguide device and method of manufacturing the same | |
| JPH06289347A (en) | Optical waveguide element and its manufacture | |
| JP2770773B2 (en) | Acousto-optic filter | |
| JP2613942B2 (en) | Waveguide type optical device | |
| JP4237932B2 (en) | Optical waveguide device and optical wavelength converter | |
| JP5316617B2 (en) | Optical waveguide device and manufacturing method thereof | |
| JP2666321B2 (en) | Optical waveguide type directional coupler | |
| JPH1078516A (en) | Production of waveguide type element and channel-shaped optical waveguide | |
| JP2900569B2 (en) | Optical waveguide device | |
| JP2001249311A (en) | Optical waveguide element | |
| JPH02118605A (en) | Manufacture of single mode optical waveguide and light modulating element using it | |
| JP2764473B2 (en) | How to make an optical waveguide | |
| JPS5936249B2 (en) | light switch | |
| JPH06331829A (en) | Attenuator for optical waveguide | |
| JPS60156039A (en) | Manufacture of optical function element | |
| JP2809112B2 (en) | Light control device and manufacturing method thereof |