JPH01129211A - Bidirectional optical tuner - Google Patents
Bidirectional optical tunerInfo
- Publication number
- JPH01129211A JPH01129211A JP28781387A JP28781387A JPH01129211A JP H01129211 A JPH01129211 A JP H01129211A JP 28781387 A JP28781387 A JP 28781387A JP 28781387 A JP28781387 A JP 28781387A JP H01129211 A JPH01129211 A JP H01129211A
- Authority
- JP
- Japan
- Prior art keywords
- diffraction grating
- lens
- optical
- optical fiber
- half mirror
- 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
- 230000003287 optical effect Effects 0.000 title claims abstract description 36
- 230000002457 bidirectional effect Effects 0.000 title claims abstract description 14
- 239000013307 optical fiber Substances 0.000 claims abstract description 41
- 239000012788 optical film Substances 0.000 claims description 2
- 230000005540 biological transmission Effects 0.000 abstract description 10
- 230000000694 effects Effects 0.000 abstract description 6
- 230000006854 communication Effects 0.000 abstract description 4
- 230000007175 bidirectional communication Effects 0.000 description 2
- 239000006185 dispersion Substances 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 1
- 230000008054 signal transmission Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/24—Coupling light guides
- G02B6/26—Optical coupling means
- G02B6/28—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals
- G02B6/293—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means
- G02B6/29379—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means characterised by the function or use of the complete device
- G02B6/29395—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means characterised by the function or use of the complete device configurable, e.g. tunable or reconfigurable
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/24—Coupling light guides
- G02B6/26—Optical coupling means
- G02B6/28—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals
- G02B6/293—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means
- G02B6/29304—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means operating by diffraction, e.g. grating
- G02B6/29305—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means operating by diffraction, e.g. grating as bulk element, i.e. free space arrangement external to a light guide
- G02B6/29308—Diffractive element having focusing properties, e.g. curved gratings
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/24—Coupling light guides
- G02B6/26—Optical coupling means
- G02B6/28—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals
- G02B6/293—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means
- G02B6/29304—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means operating by diffraction, e.g. grating
- G02B6/29305—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means operating by diffraction, e.g. grating as bulk element, i.e. free space arrangement external to a light guide
- G02B6/2931—Diffractive element operating in reflection
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/24—Coupling light guides
- G02B6/26—Optical coupling means
- G02B6/28—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals
- G02B6/293—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means
- G02B6/29304—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means operating by diffraction, e.g. grating
- G02B6/29305—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means operating by diffraction, e.g. grating as bulk element, i.e. free space arrangement external to a light guide
- G02B6/29313—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means operating by diffraction, e.g. grating as bulk element, i.e. free space arrangement external to a light guide characterised by means for controlling the position or direction of light incident to or leaving the diffractive element, e.g. for varying the wavelength response
- G02B6/29314—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means operating by diffraction, e.g. grating as bulk element, i.e. free space arrangement external to a light guide characterised by means for controlling the position or direction of light incident to or leaving the diffractive element, e.g. for varying the wavelength response by moving or modifying the diffractive element, e.g. deforming
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Optical Couplings Of Light Guides (AREA)
- Mechanical Light Control Or Optical Switches (AREA)
Abstract
Description
【発明の詳細な説明】
産業上の利用分野
本発明は、光フアイバ通信において、光波長多重伝送の
受信側に用いる双方向光チューナに関するものである。DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a bidirectional optical tuner used on the receiving side of optical wavelength division multiplexing transmission in optical fiber communications.
従来の技術
近年、光波長多重伝送技術は、光フアイバ伝送において
、−本の光ファイバをを効に活用して、複数の信号を異
なった波長にのせて送り、信号の伝送容量の増大を図る
手段として注目され、利用されている。Conventional technology In recent years, optical wavelength division multiplexing transmission technology has been developed in optical fiber transmission to effectively utilize two optical fibers to transmit multiple signals at different wavelengths, increasing the signal transmission capacity. It is attracting attention and being used as a means.
従来、上述の光波長多重伝送においては、受信側では、
光を波長分割するものとして光分波器が用いられていた
。Conventionally, in the above-mentioned optical wavelength division multiplexing transmission, on the receiving side,
Optical demultiplexers were used to split light into wavelengths.
以下、図面を参照しながら、この光分波器の一例につい
て説明する。An example of this optical demultiplexer will be described below with reference to the drawings.
第２図は従来の光分波器を示すものである。第２図にお
いて、２１は平面直線回折格子、２２はレンズ、２３は
入力光ファイバ、２４・２５・２６・２７・２８は出力
光ファイバ、２９・３０・３１・３２・３３は光−電気
変換器を示し、前記レンズ２２は前記平面直線回折格子
２１と、前記入力光ファイバ２３および前記出力光ファ
イバ２４・２５・２６・２７・２８の間に配置されてい
る。FIG. 2 shows a conventional optical demultiplexer. In Figure 2, 21 is a planar linear diffraction grating, 22 is a lens, 23 is an input optical fiber, 24, 25, 26, 27, and 28 are output optical fibers, and 29, 30, 31, 32, and 33 are optical-to-electrical converters. The lens 22 is arranged between the planar linear diffraction grating 21, the input optical fiber 23, and the output optical fibers 24, 25, 26, 27, and 28.
以上のように構成された光分波器について以下その動作
について説明する。The operation of the optical demultiplexer configured as described above will be explained below.
前記入力光ファイバ２３から、５つの異なる波長からな
る光を、前記レンズ２２を介して平面直線回折格子に入
射することによって、前記光は波長分散を受け、波長ご
とに異なる角度で反射されるとともに前記レンズで収束
され、各々波長の異なる光は出力光ファイバ２４・２５
・２６・２７・２８で受光され光−電気変換器２９・３
０・３１・３２・３３でそれぞれ電気信号に変換される
。（たとえば、ｒ１９７８年度電子通信学会技術研究報
告・Ｃ３７８−１６６，３７ページ〜４２ベージ」）
発明が解決しようとする問題点
しかしながら上記のような構成では、−度に複数の広帯
域の信号を受信するのには適しているが、何チャンネル
ものテレビ信号を一本の光ファイバで伝送する放送型の
光波長多重伝送のように、−度には一つの信号すなわち
一つの波長しか必要としない場合には、光ファイバおよ
び光−電気変換器は一組あればよく、光−電気変換器の
コストが高いことから、新しい機能の部品がのぞまれて
いた。By inputting light consisting of five different wavelengths from the input optical fiber 23 to the plane linear diffraction grating through the lens 22, the light undergoes wavelength dispersion and is reflected at different angles for each wavelength. The lights converged by the lens and having different wavelengths are output to optical fibers 24 and 25.
・The light is received at 26, 27, and 28, and the light-to-electrical converter 29, 3
0, 31, 32, and 33 are converted into electrical signals, respectively. (For example, 1978 IEICE Technical Research Report, C378-166, pages 37 to 42) Problems to be Solved by the Invention However, with the above configuration, multiple broadband signals are received at the same time. However, it is suitable for cases where only one signal, or one wavelength, is required at a time, such as broadcast-type optical wavelength division multiplexing, which transmits many channels of television signals over a single optical fiber. For this, only one set of optical fiber and optical-to-electrical converter is required, and since the cost of the optical-to-electrical converter is high, parts with new functions have been desired.
また、この様な機能に加えて、データなどの信号を送る
双方向通信が可能な新しい部品の開発が望まれていた。In addition to these functions, there was also a desire to develop new parts that could perform two-way communication to send signals such as data.
本発明は上記問題点を考慮し、放送型の光波長多重伝送
に最も適した光受信側の装置となる双方向通信が可能な
双方向光チューナを提供するものである。The present invention takes the above-mentioned problems into consideration and provides a bidirectional optical tuner capable of bidirectional communication, which is an optical receiving side device most suitable for broadcast type optical wavelength division multiplexing transmission.
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に本発明の双方向光チューナ
は、−本の入力光ファイバと、二本の出力光ファイバと
、前記入力光ファイバと二本の出力光ファイバの前方空
間に配置されたレンズと、前記レンズの前方空間に、前
記入力光ファイバの光軸に対して斜に配置された回折格
子を有し１、前記レンズと回折格子の間にハーフミラ−
を付設し、前記ハーフミラ−の法線を軸として前記光軸
にたいして対称な方向にレンズおよび光源を配置し、前
記回折格子は回転機構を備えたものである。Means for Solving the Problems In order to solve the above problems, the bidirectional optical tuner of the present invention includes: - input optical fibers, two output optical fibers, and the input optical fibers and two output optical fibers. a lens disposed in a space in front of an optical fiber; a diffraction grating disposed obliquely with respect to the optical axis of the input optical fiber in the space in front of the lens; and a half mirror between the lens and the diffraction grating. −
A lens and a light source are arranged in a direction symmetrical to the optical axis with the normal line of the half mirror as an axis, and the diffraction grating is provided with a rotation mechanism.
作用
本発明は上記した構成によって、ホログラフインク回折
格子に回転機構を持たせることによって、複数の波長の
中から必要とする波長の光だけを、−本の出力光ファイ
バで受光することができ、かつ、ハーフミラ−によって
上りの信号をも送ることのできる、簡単な構造を持った
双方向光チューナを作成することができる。Effect of the present invention With the above-described configuration, by providing the holographic ink diffraction grating with a rotation mechanism, only the light of the required wavelength from among a plurality of wavelengths can be received by the output optical fiber. Moreover, it is possible to create a bidirectional optical tuner with a simple structure that can also send up signals using a half mirror.
実施例
以下本発明の一実施例の双方向光チューナについて図面
を参照しながら説明する。EMBODIMENT A bidirectional optical tuner according to an embodiment of the present invention will be described below with reference to the drawings.
第１図は本発明における双方向光チューナを示すもので
ある。第１図において１はホログラフインク回折格子を
示す、２はレンズを示す。FIG. 1 shows a bidirectional optical tuner according to the present invention. In FIG. 1, 1 indicates a holographic ink diffraction grating, and 2 indicates a lens.
前述の構成において、前記入力光ファイバ３から５つの
異なる信号を、５つの異なる波長からなる光にのせて、
前記レンズ２を介してホログラフインク回折格子ｌに斜
に入射することによって、前記５つの異なる波長からな
る光は波長分散を受けて波長ごとに異なる角度で反射さ
れるとともに、し、ンズ２で集光され、各々波長の異な
る光の中の一つの波長Ｎの光だけが出力光ファイバ４の
端面上で焦点を結び、他の波長の光は出力光ファイバに
は入射されない。In the above-mentioned configuration, five different signals from the input optical fiber 3 are put on light consisting of five different wavelengths,
By obliquely entering the holographic ink diffraction grating l through the lens 2, the light consisting of the five different wavelengths undergoes wavelength dispersion and is reflected at different angles for each wavelength, and is focused by the lens 2. Among the different wavelengths of light, only one of the wavelengths N is focused on the end face of the output optical fiber 4, and light of other wavelengths is not input to the output optical fiber.
従って、他の波長の光を受光する時は、回転機構５を用
いて前記ホログラフィック回折格子を回転させ、所用の
波長の光を出力光ファイバに入射すればよい。６は光−
電気変換器を示し、出力光ファイバ４に入射された光を
電気信号に変換する。Therefore, when receiving light of a different wavelength, the rotation mechanism 5 may be used to rotate the holographic diffraction grating and the light of the desired wavelength may be incident on the output optical fiber. 6 is light-
An electrical converter is shown, which converts the light incident on the output optical fiber 4 into an electrical signal.
一方、上りの信号を送るときは、光源９に電気信号を載
せて、レンズ８を介してハーフミラ−７で反射させ、前
記レンズ２を介して出力光ファイバ１０に集光する。On the other hand, when sending an upward signal, an electric signal is placed on the light source 9, reflected by the half mirror 7 through the lens 8, and condensed into the output optical fiber 10 through the lens 2.
前記ハーフミラ−７は、入・出力光ファイバからの波長
の光に対しては透過し、光源からの波長の光に対しては
反射を行うような光学膜が付設されている。また、前記
ハーフミラ−７は固定されており、前記ホログラフイン
ク回折格子１の回転の如何に係わらず信号を送ることが
できる。The half mirror 7 is provided with an optical film that transmits light of the wavelength from the input/output optical fiber and reflects light of the wavelength from the light source. Furthermore, the half mirror 7 is fixed and can send signals regardless of whether the holographic ink diffraction grating 1 rotates.
特に、送信用の信号は独立した光りファイバに載せて伝
送するために、使用波長は任意に選択することができる
。In particular, the wavelength to be used can be arbitrarily selected since the transmission signal is transmitted on an independent optical fiber.
前記ボログラフインク回折格子の設定角度は、１次回折
光が入射光軸上に戻るいわゆるリトロ−角では、入力光
ファイバおよび出力光ファイバは接して配置することが
でき、小型化の点で有利である。The setting angle of the volographic ink diffraction grating is the so-called Littrow angle, where the first-order diffracted light returns to the incident optical axis, so that the input optical fiber and the output optical fiber can be arranged in contact with each other, which is advantageous in terms of miniaturization. be.
ホログラフインク回折格子は、従来の機械刻線法の回折
格子に比べて容易に作成することができる。Holographic ink diffraction gratings are easier to create than traditional mechanically scored diffraction gratings.
以上のように本実施例によればホログラフィ・７り回折
格子に、回転機構を付けることによって、従来の光分波
器に波長選択効果を持たせることができ、また、ハーフ
ミラ−によって双方向の通信をも可能にする小型で高性
能な光波長多重伝送の新しい機能の部品を提供するもの
である。As described above, according to this embodiment, by attaching a rotation mechanism to the holographic 7-dimensional diffraction grating, a conventional optical demultiplexer can have a wavelength selection effect, and the half mirror allows bidirectional The aim is to provide components with new functions for compact, high-performance optical wavelength division multiplexing transmission that also enables communication.
なお、本実施例では反射型の回折格子について述べたが
、透過型の回折格子やミラー系を含むもめについても同
様の効果が得られる。In this embodiment, a reflection type diffraction grating has been described, but similar effects can be obtained with a transmission type diffraction grating or a grating including a mirror system.
発明の効果
以上のように本発明は、ホログラフィック回折格子に回
転機構を設けることによって、波長選択効果を持たせる
ことができ、また、ハーフミラ−によって双方向の通信
をも可能にすることによって、非常に単純な形状を有す
る光学部材で双方向の光チューナを構成することができ
、放送型光波長多重伝送に適した新しい光部品を作成す
ることができる。Effects of the Invention As described above, the present invention provides a holographic diffraction grating with a rotation mechanism to provide a wavelength selection effect, and also enables bidirectional communication using a half mirror. A bidirectional optical tuner can be constructed with an optical member having a very simple shape, and a new optical component suitable for broadcast-type optical wavelength division multiplexing transmission can be created.
第１図は本発明の実施例における双方向光チューナの平
面図、第２図は従来の光分波器の斜視図であるー。
１・・・・・・ホログラフィック回折格子、２・・・・
・・レンズ、３・・・・・・入力光ファイバ、４・・・
・・・出力光ファイバ、５・・・・・・回転機構、６・
・・・・・光−電気変換器、７・・・・・・ハーフミラ
−１８・・・・・・レンズ、９・・・・・・光源、１０
・・・・・・出力光ファイバ。
代理人の氏名 弁理士 中尾敏男 はか１名／−−−ホ
ロク゛ラフスッグ５１νｒＺ了２−−−レンス゛FIG. 1 is a plan view of a bidirectional optical tuner according to an embodiment of the present invention, and FIG. 2 is a perspective view of a conventional optical demultiplexer. 1... Holographic diffraction grating, 2...
...Lens, 3...Input optical fiber, 4...
...output optical fiber, 5...rotation mechanism, 6.
.....Light-to-electrical converter, 7.....Half mirror 18.....Lens, 9.....Light source, 10
...Output optical fiber. Name of agent: Patent attorney Toshio Nakao 1 person/---Horokurafusug51νrZR2---Rense
Claims (3)
と、前記入力光ファイバと二本の出力光ファイバの前方
空間に配置されたレンズと、前記レンズの前方空間に、
前記入力光ファイバの光軸に対して斜に配置された回折
格子とを有し、前記レンズと回折格子の間にハーフミラ
ーを付設し、前記ハーフミラーの法線を軸として前記光
軸にたいして対称な方向にレンズおよび光源を配置し、
前記回折格子は回転機構を具備して成ることを特徴とす
る双方向光チューナ。(1) one input optical fiber, two output optical fibers, a lens disposed in a space in front of the input optical fiber and the two output optical fibers, and a space in front of the lens,
a diffraction grating arranged obliquely with respect to the optical axis of the input optical fiber, a half mirror is attached between the lens and the diffraction grating, and is symmetrical with respect to the optical axis with the normal line of the half mirror as an axis. Place the lens and light source in the correct direction,
A bidirectional optical tuner characterized in that the diffraction grating is equipped with a rotation mechanism.
対しては透過し、光源からの波長の光に対しては反射を
行うような光学膜を具備して成ることを特徴とする特許
請求の範囲第（１）項記載の双方向光チューナ。(2) A patent claim characterized in that the half mirror is equipped with an optical film that transmits light at a wavelength from an input optical fiber and reflects light at a wavelength from a light source. A bidirectional optical tuner according to item (1).
とを特徴とする特許請求の範囲第（１）項記載の双方向
光チューナ。(3) The bidirectional optical tuner according to claim (1), characterized in that a holographic diffraction grating is used as the diffraction grating.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP28781387A JPH01129211A (en) | 1987-11-13 | 1987-11-13 | Bidirectional optical tuner |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP28781387A JPH01129211A (en) | 1987-11-13 | 1987-11-13 | Bidirectional optical tuner |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01129211A true JPH01129211A (en) | 1989-05-22 |
Family
ID=17722091
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP28781387A Pending JPH01129211A (en) | 1987-11-13 | 1987-11-13 | Bidirectional optical tuner |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01129211A (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58194011A (en) * | 1982-05-10 | 1983-11-11 | Nippon Telegr & Teleph Corp <Ntt> | Optical demultiplexer of two-way transmission |
| JPS59159124A (en) * | 1983-03-01 | 1984-09-08 | Nippon Telegr & Teleph Corp <Ntt> | Light demultiplexing coupler for two-way transmission |
| JPS62115403A (en) * | 1985-11-15 | 1987-05-27 | Matsushita Electric Ind Co Ltd | Optical tuner |
-
1987
- 1987-11-13 JP JP28781387A patent/JPH01129211A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58194011A (en) * | 1982-05-10 | 1983-11-11 | Nippon Telegr & Teleph Corp <Ntt> | Optical demultiplexer of two-way transmission |
| JPS59159124A (en) * | 1983-03-01 | 1984-09-08 | Nippon Telegr & Teleph Corp <Ntt> | Light demultiplexing coupler for two-way transmission |
| JPS62115403A (en) * | 1985-11-15 | 1987-05-27 | Matsushita Electric Ind Co Ltd | Optical tuner |
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