JPS60184215A - Optical multiplexer/demultiplexer - Google Patents
Optical multiplexer/demultiplexerInfo
- Publication number
- JPS60184215A JPS60184215A JP3875184A JP3875184A JPS60184215A JP S60184215 A JPS60184215 A JP S60184215A JP 3875184 A JP3875184 A JP 3875184A JP 3875184 A JP3875184 A JP 3875184A JP S60184215 A JPS60184215 A JP S60184215A
- Authority
- JP
- Japan
- Prior art keywords
- interference film
- glass body
- face
- film filter
- reflected
- 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.)
- Granted
Links
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
- G02B6/2938—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 for multiplexing or demultiplexing, i.e. combining or separating wavelengths, e.g. 1xN, NxM
-
- 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
- G02B6/29346—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 wave or beam interference
- G02B6/29361—Interference filters, e.g. multilayer coatings, thin film filters, dichroic splitters or mirrors based on multilayers, WDM filters
- G02B6/29362—Serial cascade of filters or filtering operations, e.g. for a large number of channels
- G02B6/29365—Serial cascade of filters or filtering operations, e.g. for a large number of channels in a multireflection configuration, i.e. beam following a zigzag path between filters or filtering operations
- G02B6/29367—Zigzag path within a transparent optical block, e.g. filter deposited on an etalon, glass plate, wedge acting as a stable spacer
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Optical Couplings Of Light Guides (AREA)
- Optical Filters (AREA)
Abstract
Description
【発明の詳細な説明】 （技術分野） 本発明は、光合分波器の改良に関するものである。[Detailed description of the invention] (Technical field) The present invention relates to improvement of optical multiplexer/demultiplexer.
（従来技術）
従来、このような分野に１本の光ファイバ中に異なる波
長の光信号を結合または分，離−する機能を持つ光合分
波器は数多く報告されている。例えば、昭和５８年度電
子通信学会総合全国大会のｒ２２’６７光合分庭器にお
ける色収差低減方法の検討」に記載されている。(Prior Art) Many optical multiplexers/demultiplexers having the function of combining or separating optical signals of different wavelengths into a single optical fiber have been reported in this field. For example, it is described in ``Study of Chromatic Aberration Reduction Method in R22'67 Optical Combining and Dividing Device'' of the 1985 National Conference of the Institute of Electronics and Communication Engineers.
第１図は、従来の４波川光合分波器の一構成例を示すも
ので、３つの光学研磨面を持つガラス体１の一面ｌａに
異種の干渉膜フィルタ２ａ，２ｂ，２ｃ，２ｄが並列配
置されている。又、ガ゛．ラス体１の他の二面１ｂお’
ｔ’５’ｉｃにはロッドレンズ３ａ，３ｂ．．，３ｃ，
＠ｄおよび３ｅが密着接合されておシ、対応する光ファ
イバ４ａ＋４ｂ＋４ｃ＋４ｄおよび４ｅからの光信号を
平行ビームに変換している。一方、前記ガラス体１の一
面１ａには、反射膜５を形成した平行ガラス体６が、前
記干渉膜フィルタ２ａ，２ｂ＋２ｃ，２ｄを介して密着
接合している。なお、前記ガラス体１の一面ｌｂにはロ
ッドレンズ３ｄが干渉膜フィルタ２ｅを介して密着接合
されている。Figure 1 shows an example of the configuration of a conventional four-wave optical multiplexer/demultiplexer, in which different types of interference film filters 2a, 2b, 2c, and 2d are arranged in parallel on one surface la of a glass body 1 having three optically polished surfaces. It is located. Also, Gai. Other two faces 1b o' of lath body 1
t'5'ic has rod lenses 3a, 3b. ．． ,3c,
@d and 3e are closely joined to convert the optical signals from the corresponding optical fibers 4a+4b+4c+4d and 4e into parallel beams. On the other hand, a parallel glass body 6 on which a reflective film 5 is formed is tightly bonded to one surface 1a of the glass body 1 via the interference film filters 2a, 2b+2c, 2d. A rod lens 3d is tightly bonded to one surface lb of the glass body 1 via an interference film filter 2e.
以上の如き構成の光合分波器では、光ファイバ４ｅを共
通ポートとし、その他の光ファイノ寸４ａ，４ｂ，４ｃ
，４ｄを送信または受信ポートとして作用する。すなわ
ち、光ファイバ４ｅからの光信号はロンドレンズ３ｅで
平行ビーム化され、ガラス体１の干渉膜フィルタ２′？
Ｉであらかじめ設定した特定の波長を持つ光のみが反射
され、干渉膜フィルタ２ｅを経て光ファイバ４ｄへ結合
される。In the optical multiplexer/demultiplexer configured as above, the optical fiber 4e is used as a common port, and the other optical fibers have dimensions 4a, 4b, 4c.
, 4d act as transmit or receive ports. That is, the optical signal from the optical fiber 4e is converted into a parallel beam by the Rondo lens 3e, and is passed through the interference film filter 2'? of the glass body 1.
Only light having a specific wavelength set in advance by I is reflected and coupled to the optical fiber 4d via the interference film filter 2e.
一方、干渉膜フィルタ２ｄを通過したその他の波長を持
つ光は、平行ガラス休６０反射膜５で反射し、干渉膜フ
ィルタ２Ｃへと進み、以下、上述と同様の作様を繰り返
して特定の光ファイバ４ｃ，４ｂ，４ａと順に結合され
、光合分波器としての機能が得られるのである。On the other hand, the light having other wavelengths that has passed through the interference film filter 2d is reflected by the parallel glass filter 60 and the reflection film 5, and proceeds to the interference film filter 2C. It is coupled to fibers 4c, 4b, and 4a in order, and functions as an optical multiplexer/demultiplexer.
なお、前記作−用は、光の進行方向が逆であっても同様
に行々われることは説明するまでもない。It goes without saying that the above-mentioned action is performed in the same way even if the direction of light travels is reversed.
しかしながら、上記構成の光合分波器では以下の如き問
題点が生じるのである。すなわち、（１）−共通月？一
ト用の光ファイバ４ｅとその他のポート用の光ファイバ
４ａ，４ｂ，４ｃ，４’ｄが平行に配置されていないの
で形状が大きくなるとともに、光合分波器としての取り
付け実装条件の制約が厳しくなる。However, the optical multiplexer/demultiplexer with the above configuration has the following problems. That is, (1) - common month? Since the optical fiber 4e for one port and the optical fibers 4a, 4b, 4c, and 4'd for other ports are not arranged in parallel, the shape becomes larger and there are restrictions on installation conditions as an optical multiplexer/demultiplexer. It gets tough.
（２）ガラス体１の形状が複雑で、かつ反射膜５を形成
した平行ガラス体６を別部品として用意し、しかも組立
てに際して干渉膜フィルタ２ａ〜２ｄを同時にはさんで
貼９合せる複雑な作業を伴なう。(2) The shape of the glass body 1 is complicated, and the parallel glass body 6 on which the reflective film 5 is formed is prepared as a separate part, and the interference film filters 2a to 2d are simultaneously sandwiched and laminated together during assembly. accompanied by.
特に、干渉膜フィルタ２ａ〜２ｄの厚さにパラツキがあ
る場合には、それらの一部に接着剤による空隙が出来、
したがって光透過率が低下し、例えば光結合損失が増犬
ずる等、信頼性に之しいものとなる。In particular, if there are variations in the thickness of the interference film filters 2a to 2d, voids may be formed in some of them due to the adhesive.
Therefore, the light transmittance decreases and, for example, the optical coupling loss increases, which impairs reliability.
（３）ロノドレンズ３とガラス体１との間は光学用の接
着剤で固定されており、両者間に生じる光の反射は前記
接着剤の屈折率の効果によってある程度は避けることは
出来るのであるが、少なくともロンドレンズの材質とガ
ラス体の材質の屈折率の差異による不整合反射は避ける
ことが出来ない。(3) The Ronodo lens 3 and the glass body 1 are fixed with an optical adhesive, and the reflection of light between them can be avoided to some extent by the effect of the refractive index of the adhesive. At least, mismatched reflection due to the difference in refractive index between the material of the Rondo lens and the material of the glass body cannot be avoided.
等の問題点が生じるのである。Problems such as these arise.
（発明の目的）
本発明はこのような問題点を除去する為になされたもの
であって、取９付け実装条件の自由度力５得られ、シン
プルガ構成で、しかも反射光の影響を受けない光合分波
器を提供することを目的とするものである。(Objective of the Invention) The present invention has been made to eliminate these problems, and has a simple configuration with 9 degrees of freedom in mounting conditions, and is not affected by reflected light. The purpose is to provide an optical multiplexer/demultiplexer.
（発明の構成）
すなわち、本発明は、異表る波長通過域を持つ複数の干
渉膜フィルタを配置した第１の面と、該第１の面と平行
に対向して全反射面を有する第２の面と、第１と第２の
面に直交する光学研磨面を有する第３の面とを備えるガ
ラス体と、互いに平行して配した複数のポートとを用い
、しかも、この複数の月？一トを前記ガラス体の第１の
面に対向させて配置して構成したもので、これにより前
記目的を達成するものである。以下、図面を用いて本発
明を説明する。(Structure of the Invention) That is, the present invention has a first surface on which a plurality of interference film filters having different wavelength passbands are arranged, and a total reflection surface facing parallel to the first surface. A glass body having a second surface and a third surface having an optically polished surface perpendicular to the first and second surfaces, and a plurality of ports arranged in parallel to each other, ? The glass body is constructed by arranging one plate facing the first surface of the glass body, thereby achieving the above object. The present invention will be explained below using the drawings.
（発明の実施例）
第２図は本発明に係る光合分波器の一実施例を示す構成
図であって、コリメータ、ここではボールレンズ１１と
光ファイノぐ１２を一体化した複数のコリメータ１３、
ここでは５本のコリメータ１３ｈ，１３ｂ，１３ｃ，１
３ｄおよび１３ｅを平行に配置している。又、ガラス体
１４は互いに平行な二而１４ａ，１４ｂと、これに直交
する面１４ｃの３つの平滑面を形成して成る。そして、
前記面１４ａには異った波長通過域を持つ複数の干渉膜
フィルタ１５ａ，１５ｂ，１５ｃ，１５ｄが並列に配置
され、該面１４ａに対向し、平行に形成する面１４ｂに
は反射ミラ−１６が密着あるいは蒸着処理等が設けられ
ている。又、面１４ｃは平滑研磨が施されているのみで
ある。そして、前記の如く成るコリメータ１３とガラス
体１４の位置関係は、共通目？一ト用のコリメータ１３
ａからの平行ビームは一旦空気中に露出し、次いで、ガ
ラス体１４の面Ｉ４ａの一部に干渉膜フイノレタ１５を
経ず、しかも斜めに入射する如く設定、配置されている
。(Embodiment of the Invention) FIG. 2 is a configuration diagram showing an embodiment of the optical multiplexer/demultiplexer according to the present invention, in which a plurality of collimators 13 are integrated, in which a ball lens 11 and an optical fiber optic 12 are integrated. ,
Here, five collimators 13h, 13b, 13c, 1
3d and 13e are arranged in parallel. Further, the glass body 14 has three smooth surfaces, two surfaces 14a and 14b parallel to each other and a surface 14c perpendicular to these two surfaces. and,
A plurality of interference film filters 15a, 15b, 15c, and 15d having different wavelength passbands are arranged in parallel on the surface 14a, and a reflection mirror 16 is arranged on the surface 14b facing and parallel to the surface 14a. However, adhesion or vapor deposition treatment is provided. Further, the surface 14c is only polished smooth. Is the positional relationship between the collimator 13 and the glass body 14 as described above common? Collimator 13 for one person
The parallel beam from a is once exposed in the air, and then is set and arranged so that it is incident obliquely on a part of the surface I4a of the glass body 14 without passing through the interference film finometer 15.
この時、空気とガラスの屈折率の違いによって生ずる反
射光は、入射ビームの方向とは異なるのでコリメータｌ
３ａ〜１３ｅ内の光ファイノξ１２へは結合しない。す
なわち、反射光の影響は受けない構成となっているので
ある。At this time, the reflected light caused by the difference in refractive index between air and glass is different from the direction of the incident beam, so the collimator l
It is not coupled to the optical fiber ξ12 in 3a to 13e. In other words, the structure is such that it is not affected by reflected light.
以１−の構成に１，・いて、共通，．＋９｝であるコリ
メータ１３ａを経た光ファイバ１２ａからの光ビー！、
Ｃ１、先ず、ガラス体１４の第１の面１４ａを経て第：
−３の面１４ｃで全反射し、更に、第２の面１４１１に
設けた反射ミラーＪ６でも全反射し”、干渉膜フィルタ
１５ａに達する。この干渉膜フィルタ１５ａでは、特定
の波長を持つ光のみが通過しコリメ−タ１３ｂに結合さ
れる。又、他の波長を持つ光は干渉膜フィルタ１５ａ，
反射ミラーｌ６で１１び反射し、次の干渉膜フィルタ１
．５ｂへ達し、以下、同様の作用が行なわれ、分波作用
が行々われるのである。なお、光の進路はこの逆でも同
様で、その場合は分波器として作用することは明白であ
る。In the configuration of 1- below, 1, · has common, . +9} is the light beam from the optical fiber 12a that passes through the collimator 13a! ,
C1, first, through the first surface 14a of the glass body 14:
-3 surface 14c, and is further totally reflected by the reflection mirror J6 provided on the second surface 1411, reaching the interference film filter 15a.In this interference film filter 15a, only light having a specific wavelength is reflected. The light passes through and is coupled to the collimator 13b.In addition, light having other wavelengths passes through the interference film filters 15a,
It is reflected 11 times by the reflection mirror l6, and the next interference film filter 1
．． 5b, and the same operation is performed thereafter, and a demultiplexing operation is performed. Note that the path of light is the same even in the opposite direction, and in that case it is clear that it acts as a demultiplexer.
（発明の効果）
以上、詳細に説明したように本発明によれば、片面に干
渉膜フィルタを、これと対向する他面に反射ミラーを配
したガラス体を用い、更に、共通，Ｉ？｝からの光ビー
ムをガラス体の内部側面で全反射させる構成としたこと
によって、
（】）共通ポートも含めて全ポートが同側に、しかも平
行に配置出来ることとなり、小形になり、取シ付け実装
性に自由度が増大する。換言すると、取り付けに際して
の無駄々空間がなくなるのである。(Effects of the Invention) As described above in detail, according to the present invention, a glass body having an interference film filter on one side and a reflection mirror on the other side facing the glass body is used, and furthermore, a common, I? } By completely reflecting the light beam from the inside surface of the glass body, all ports including the common port can be placed on the same side and in parallel, resulting in a smaller size and easier installation. The degree of freedom in mounting increases. In other words, there is no wasted space during installation.
（２）構成が極めて簡単で、しかも個．々の部品につい
て高い寸法精度が不要である。(2) The configuration is extremely simple and individual. High dimensional accuracy is not required for each part.
（３）光ビームがガラス体平面に７Ｊシて垂直に人、出
射しない為に反射光の影響を受けない。すなわち、無反
射型の光合分波器が実現出来る。(3) Since the light beam is not emitted perpendicularly to the plane of the glass body, it is not affected by reflected light. In other words, a non-reflective optical multiplexer/demultiplexer can be realized.
等の優れた効果が期待出来るのである。Excellent effects such as these can be expected.
第１図は従来の光合分波器の一構成例を示す図であり、
第２図は本発明に係る光合分波器の一実施例を示す図で
ある。
１はガラス体、２ａ，２ｂ，２ｃ，２ｄ，２ｅは干渉膜
フィルタ、３ａ，．ｉｂ＋．？ｃ，３ｄ，．ｉｅは０，
／ドレンズ、４ａ，４ｂ．４ｃ，４ｄ，４ｅは光ファイ
バ、５は反射膜、６は平行ガラス体、１１１ｄ？−ルレ
ンズ、１２は光ファイバ、ｌ３ａ，１３ｂ，Ｉ．’ｌｃ
，１３ｄ，１３ｅはコリメータ、１４はガラス体、Ｉ．
５ａ，１５ｂ，１．５ｃ，１５ｄは干渉膜フィルタ、ｌ
６は反射ミラーである。
肪許出願人沖電気工業株式会社
代理人￥）木敏り（需９FIG. 1 is a diagram showing an example of the configuration of a conventional optical multiplexer/demultiplexer.
FIG. 2 is a diagram showing an embodiment of an optical multiplexer/demultiplexer according to the present invention. 1 is a glass body, 2a, 2b, 2c, 2d, 2e are interference film filters, 3a, . ib+. ? c, 3d, . ie is 0,
/ Drens, 4a, 4b. 4c, 4d, 4e are optical fibers, 5 is a reflective film, 6 is a parallel glass body, 111d? - lens, 12 is an optical fiber, l3a, 13b, I. 'lc
, 13d, 13e are collimators, 14 is a glass body, I.
5a, 15b, 1.5c, 15d are interference film filters, l
6 is a reflecting mirror. License applicant Oki Electric Industry Co., Ltd. Agent ￥) Toshiri Ki (Demand 9)
Claims (2)
渉膜フィルタを配置し、第１の面と平行に対向する第２
′の面ば全反射面と成し、更に、第１と第２の面に直交
する第３の面を光学研磨面としたガラス体と、該ガラス
体の第１の面に対向し、しかも互いに平行して配置した
複数のポートとを用いて構成したことを特徴とする光合
分波器。(1), A plurality of interference film filters with different wavelength passbands are arranged on the first surface, and a second filter facing parallel to the first surface is arranged.
a glass body whose surface is a total reflection surface and whose third surface perpendicular to the first and second surfaces is an optically polished surface; An optical multiplexer/demultiplexer characterized in that it is constructed using a plurality of ports arranged in parallel to each other.
ータとしたことを特徴とする特許請求の範囲第（１）項
記載の光合分波器。(2) Said, l? 1. The optical multiplexer/demultiplexer according to claim 1, wherein l is a collimator using pole lenses.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3875184A JPS60184215A (en) | 1984-03-02 | 1984-03-02 | Optical multiplexer/demultiplexer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3875184A JPS60184215A (en) | 1984-03-02 | 1984-03-02 | Optical multiplexer/demultiplexer |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS60184215A true JPS60184215A (en) | 1985-09-19 |
| JPS6330605B2 JPS6330605B2 (en) | 1988-06-20 |
Family
ID=12533998
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3875184A Granted JPS60184215A (en) | 1984-03-02 | 1984-03-02 | Optical multiplexer/demultiplexer |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS60184215A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003504661A (en) * | 1999-07-02 | 2003-02-04 | ブレイズ、ネットワーク、プロダクツ、インコーポレーテッド | Optical wavelength division multiplexer / demultiplexer in which preformed optical components are passively aligned |
| CN100422777C (en) * | 2002-11-01 | 2008-10-01 | 欧姆龙株式会社 | Optical multiplexer/demultiplexer and production method for optical multiplexer/demultiplexer |
| JP2008286961A (en) * | 2007-05-17 | 2008-11-27 | Hitachi Ltd | Optical multiplexer/demultiplexer |
| CN110531472A (en) * | 2019-09-24 | 2019-12-03 | 武汉光迅科技股份有限公司 | A kind of light emitting devices, light receiving element and optical module |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS55155204U (en) * | 1979-04-24 | 1980-11-08 |
-
1984
- 1984-03-02 JP JP3875184A patent/JPS60184215A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS55155204U (en) * | 1979-04-24 | 1980-11-08 |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003504661A (en) * | 1999-07-02 | 2003-02-04 | ブレイズ、ネットワーク、プロダクツ、インコーポレーテッド | Optical wavelength division multiplexer / demultiplexer in which preformed optical components are passively aligned |
| CN100422777C (en) * | 2002-11-01 | 2008-10-01 | 欧姆龙株式会社 | Optical multiplexer/demultiplexer and production method for optical multiplexer/demultiplexer |
| JP2008286961A (en) * | 2007-05-17 | 2008-11-27 | Hitachi Ltd | Optical multiplexer/demultiplexer |
| CN110531472A (en) * | 2019-09-24 | 2019-12-03 | 武汉光迅科技股份有限公司 | A kind of light emitting devices, light receiving element and optical module |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6330605B2 (en) | 1988-06-20 |
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Legal Events
| Date | Code | Title | Description |
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| EXPY | Cancellation because of completion of term |