JP4278192B2 - Optical waveguide, optical multiplexer / demultiplexer, optical parallel bus, and optoelectronic integrated device - Google Patents

Description

【００３５】
となる。ここで、ａはクラッドの半径（＝光ファイバの半径）である。
【００３６】
従って、第１の光ファイバＯｆ１内のスポットサイズをω_A 、第２の光ファイバＯｆ２内のスポットサイズをω_B とすると、両者の比ω_A ／ω_B は、式(1) より、
【００３７】
【数２】

【００３８】
となる。ここで、光ビームの波長をλとすると、パラメータαは、α＝πω_A ² ／λａであり、等価的に光ビームのスポットの大きさを表している。
【００３９】
また、結合効率ηは、
【００４０】
【数３】

【００４１】
と表される。
【００４２】
ここで、クラッドの屈折率ｎ_c をパラメータとして、結合効率ηとパラメータαとの関係を示すと、図３のようになる。図３において、パラメータαが２となる付近で結合効率ηが最も高く、１となり、パラメータαがさらに大きくなるにつれて、結合効率ηが下がっていくことが分かる。
【００４３】
次に、結合効率η＝１となる条件を求めると、式(2),(3) より、
【００４４】
【数４】

【００４５】
となる。
【００４６】
この式(4) におけるパラメータαとクラッドの屈折率ｎ_c との関係を示すと図４のようになる。
【００４７】
従って、図３及び図４より、パラメータα及びクラッドの屈折率ｎ_c を適宜選択することにより、結合効率ηを１とすることができることが分かる。また、この結合効率ηが１となる条件は、式(4) より、コア１の等価屈折率ｎ_e ，クラッド２の屈折率ｎ_c ，及びパラメータαにより定まり、またパラメータαは、光ファイバのスポットサイズω，クラッドの半径ａ，及び光ビームの波長λにより定まる。また、上記では、光導波路の周囲の媒質が空気であると仮定して解析しているが、光導波路の周囲の媒質が空気以外の物質である場合には、その媒質の屈折率に応じて、上記解析結果を補正すればよい。従って、結合効率ηが１となる条件は、入射せしめる光ビームの波長λと、光ファイバの構造が定まれば一義的に定まることとなる。
【００４８】
次に、第１の光ファイバＯｆ１と第２の光ファイバＯｆ２とが離れている場合を説明する。第１の光ファイバＯｆ１と第２の光ファイバＯｆ２との間隔（以下、光ファイバ間隔と記載する）をｄ、クラッド半径ａに対する光ファイバ間隔ｄの比（以下、クラッド半径に対する比で表した光ファイバ間隔と記載する）ｄ／ａをＤとし、上記と同様に結合効率ηが１となる条件を求めると、
【００４９】
【数５】

【００５０】
となる。従って、式(5) を満たすようにすることにより、第１の光ファイバＯｆ１と第２の光ファイバＯｆ２とが離れていても、結合効率ηを１とすることができることが分かる。
【００５１】
また、式(5) より、クラッド半径に対する比で表した光ファイバ間隔Ｄに関しては、以下の条件が満足されなければならない。
【００５２】
【数６】

【００５３】
この式(5) におけるパラメータαとクラッド半径に対する比で表した光ファイバ間隔Ｄとの関係を、クラッドの屈折率ｎ_c をパラメータとして示すと図５のようになる。図５において、任意の屈折率ｎ_c に対し、クラッド半径に対する比で表した光ファイバ間隔Ｄが小さい領域では、結合効率ηが１となるパラメータαが存在するが、クラッド半径に対する比で表した光ファイバ間隔Ｄがある値以上となると、その領域では、結合効率ηが１となるパラメータαが存在しない。従って、第１の光ファイバＯｆ１と第２の光ファイバＯｆ２とが一定以上離れると、結合効率ηを１とすることができないことが分かる。
【００５４】
従って、本実施の形態１では、光ファイバ間隔ｄは、式(5) を満たすように設定され、この設定は、入射せしめる光ビームの波長に応じて、第１の光ファイバＯｆ１内のスポットサイズω_A ，第２の光ファイバＯｆ２内のスポットサイズω_B ，クラッドの半径ａ，及びクラッドの屈折率ｎ_c を適宜選択することにより、該光ファイバ間隔ｄが所望の値となるように行われる。また、第１，第２の光ファイバ内のスポットサイズω_A ，ω_B は、コア１のドーパント等の熱拡散技術等を用いると比較的容易に変化させることができる。
【００５５】
次に、第１の光ファイバＯｆ１と第２の光ファイバＯｆ２との接続部の偏波特性について説明する。
【００５６】
図２に示すように、本実施の形態１による光導波路では、互いに直角にねじれた位置関係にある２つの傾斜端面Ｆ１，Ｆ２で、光ファイバに入射せしめた光ビームを反射するため、光ビームは、一方の傾斜端面でＴＭライク入射すると、他方の傾斜端面ではＴＥライク入射（あるいは、その逆）する。従って、基本的に、第１の光ファイバＯｆ１と第２の光ファイバＯｆ２との接続部では、偏波無依存性を示す。
【００５７】
次に、以上のように構成された光導波路の動作を図１，２を用いて説明する。これらの図において、第１の光ファイバＯｆ１の他端に所定の波長λの光ビームを入射せしめると、入射した光ビームは、第１の光ファイバＯｆ１の中心部を中心軸Ａｘ１に沿ってスポットサイズω_A で伝搬し、第１の光ファイバＯｆ１の傾斜端面Ｆ１の中心点Ｃｐ１で該傾斜端面Ｆ１の中心軸Ａｘ４に対し４５°の角度で反射し、第１の光ファイバ／第２の光ファイバ直交軸Ａｘ３に沿って第１の光ファイバＯｆ１の側面，及び第２の光ファイバＯｆ２の側面を通過し、第２の光ファイバＯｆ２の傾斜端面Ｆ２で該傾斜端面Ｆ２の中心軸Ａｘ５に対し４５°の角度で反射し、第２の光ファイバＯｆ２の中心部を中心軸Ａｘ２に沿ってスポットサイズω_B で伝搬し、該第２の光ファイバＯｆ２の他端から出射される。
【００５８】
この際に、第１の光ファイバの傾斜端面Ｆ１の中心Ｃｐ１で反射された光ビームは、該第１の光ファイバＯｆ１の半径方向には光の閉じ込め構造が存在しないため径が拡がり、この径の拡がった光ビームは、互いに９０°ねじれた位置関係にある第１，第２の光ファイバＯｆ１，Ｏｆ２の側面により、該光ビームの横断面方向において均等な収束効果を受ける。ここで、上記解析モデルによる解析により求めた光ファイバ間隔ｄは、第１の光ファイバの傾斜端面Ｆ１の中心Ｃｐ１で反射されて径が拡がった光ビームが上記収束効果を受けて、第２の光ファイバＯｆ２内を伝搬する際のスポットサイズω_B と同じ径を有するものとなる位置に、該第２の光ファイバの傾斜端面Ｆ２の中心Ｃｐ２が位置するような間隔であるので、上記収束効果を受けた光ビームは、第２の光ファイバの傾斜端面Ｆ２の中心Ｃｐ２にて、該第２の光ファイバＯｆ２内のスポットサイズω_B と同じ径を有するものとなり、該第２の光ファイバの傾斜端面Ｆ２で反射された光ビームの全部が該第２の光ファイバＯｆ２のコア１に入射する。従って、両光ファイバＯｆ１，Ｏｆ２間の結合効率ηが１となる。
【００５９】
また、第２の光ファイバＯｆ２の他端に所定の波長λの光ビームを入射せしめると、入射した光ビームは、上記と全く逆の経路を辿り、上記と同様にして結合効率１でもって第２の光ファイバＯｆ２から第１の光ファイバＯｆ１に伝搬し、該第１の光ファイバＯｆ１の他端から出射される。
【００６０】
なお、上記の説明では、第１，第２の光ファイバＯｆ１，Ｏｆ２と第１の光ファバ／第２の光ファイバ直交軸Ａｘ３との交差角、第１の光ファイバＯｆ１と第２の光ファイバＯｆ２との交差角、各光ファイバの傾斜端面Ｆ１，Ｆ２の傾斜角、及び光ファイバ間隔ｄが理想値であるものとしているが、図３のグラフから推測されるように、これら各角度，及び光ファイバ間隔ｄが理想値から若干ずれたとしても、光ファイバ間の結合効率は急激に低下するものではない。従って、これら各角度，及び光ファイバ間隔ｄは、理想値に近い範囲内で、必要とされる結合効率に応じた値に設定することができる。
【００６１】
また、光ファイバ間隔ｄを理論式により求めているが、これを、例えば、結合効率が極大となる光ファイバ間隔ｄを検出するような実験により求めてもよい。
【００６２】
また、第１の光ファイバＯｆ１と第２の光ファイバＯｆ２とは、同一構造のものであるとしているが、両光ファイバの屈折率及び径は異なっていてもよい。この場合、光ビームが両光ファイバの側面により受ける収束効果が、上記で説明した収束効果と同等となるように両光ファイバの屈折率及び径を定めることにより、上記で説明したのと同様にして光ファイバ間隔ｄを設定することができる。
【００６３】
また、光導波部材として、コア１とクラッド２とからなる光ファイバを用いているが、その半径方向に徐々に小さくなるように屈折率を変化せしめてなるロッドレンズを用いてもよい。
【００６４】
また、光導波部材は、中心軸方向に一定な径を有するものとしているが、中心軸方向に変化する径を有するものであってもよい。
【００６５】
また、光導波部材は、直線状であるとしているが、傾斜端面の近傍が直線状であればよく、傾斜端面を有しない方の端部は曲がっていてもよい。
【００６６】
以上のように、本実施の形態１の光導波路によれば、一方の光ファイバに入射せしめた光ビームが、他方の光ファイバに略１の結合効率でもって伝搬され、かつ双方の光ファイバが、第１の光ファイバ／第２の光ファイバ直交軸Ａｘ３方向から見て、互いの傾斜端面が重なりかつ互いに直角に交差するように配置されているため、光配線を高結合効率でもって直角方向に引き回すことが可能となる。
【００６７】
また、本実施の形態１の光導波路によれば、互いの側面により光ビームに対する収束効果を生ぜしめる光ファイバ間隔ｄを所定の理論式により定めたものとしたので、該光ファイバ間隔ｄを容易に設定することができる。
【００６８】
実施の形態２．
図６は本発明の実施の形態２による光導波路の構成を示す図であり、図６(a) は斜視図、図６(b) は図６(a) のＡ矢示図、図６(c) は図６(a) のＢ矢示図である。図において、図１と同一符号は同一又は相当する部分を示し、本実施の形態２による光導波路は、実施の形態１の第１，第２の光ファイバＯｆ１，Ｏｆ２とロッドレンズ１００とで構成される。ロッドレンズ１００は、横断面が円形で中心軸Ａｘ６方向に径が一定な線形状を有しており、例えば、第１，第２の光ファイバＯｆ１，Ｏｆ２と同じ径を有し、同じ材料で構成される。また、ロッドレンズ１００の屈折率は、例えば、第１，第２の光ファイバＯｆ１，Ｏｆ２のクラッドの屈折率と同じとされる。
【００６９】
そして、第１の光ファイバＯｆ１，第２の光ファイバＯｆ２，及びロッドレンズ１００は、第２の光ファイバＯｆ２の傾斜端面Ｆ２の中心Ｃｐ２が、第１の光ファイバＯｆ１の傾斜端面Ｆ１の中心Ｃｐ１にて該傾斜端面Ｆ１の中心軸Ａｘ４を挟むようにして第１の光ファイバの中心軸Ａｘ１に直交する第１の光ファイバ／第２の光ファイバ直交軸Ａｘ３上に位置し、第２の光ファイバＯｆ２の中心軸Ａｘ２が、該第２の光ファイバの傾斜端面Ｆ２の中心軸Ａｘ５を挟むようにして第１の光ファイバ／第２の光ファイバ直交軸Ａｘ３に直交するとともに該第１の光ファイバ／第２の光ファイバ直交軸Ａｘ３方向から見て第１の光ファイバの中心軸Ａｘ１に対して０度の交差角を有し（第１の光ファイバの中心軸Ａｘ１に重なり）、第１の光ファイバの傾斜端面Ｆ１と第２の光ファイバの傾斜端面Ｆ２とが、第１の光ファイバ／第２の光ファイバ直交軸Ａｘ３方向から見て互いに反対の方向を向き、ロッドレンズ１００の中心軸Ａｘ６が、第１の光ファイバＯｆ１と第２の光ファイバＯｆ２との間にて第１の光ファイバ／第２の光ファイバ直交軸Ａｘ３に直交するとともに該第１の光ファイバ／第２の光ファイバ直交軸Ａｘ３方向から見て第１の光ファイバの中心軸Ａｘ１及び第２の光ファイバの中心軸Ａｘ２に垂直となり、かつ、第１の光ファイバＯｆ１とロッドレンズ１００との間隔，及び第２の光ファイバＯｆ２とロッドレンズ１００との間隔が、実施の形態１で述べた結合効率ηが１となる所定の間隔となるように配置されている。
【００７０】
次に、このように構成された光導波路は、第１の光ファイバＯｆ１とロッドレンズ１００との位置関係、及びロッドレンズ１００と第２の光ファイバＯｆ２との位置関係が実施の形態１の第１の光ファイバＯｆ１と第２の光ファイバＯｆ２との位置関係と同じになる。従って、第１の光ファイバＯｆ１とロッドレンズ１００との間隔、及びロッドレンズ１００と第２の光ファイバＯｆ２との間隔を、実施の形態１の光ファイバ間隔ｄと同様に設定することにより、第１の光ファイバＯｆ１とロッドレンズ１００との間、及びロッドレンズ１００と第２の光ファイバＯｆ２との間にて、光ビームを結合効率１でもって伝搬せしめることができる。
【００７１】
ここで、第１の光ファイバの傾斜端面Ｆ１の中心点Ｃｐ１と第２の光ファイバの傾斜端面Ｆ２の中心点Ｃｐ２とにおいて光ビームの径が同じであれば、一方の光ファイバのコア１から出射された光ビームは全て他方の光ファイバのコア１に入射することとなり、結合効率が１となるため、第１の光ファイバの傾斜端面Ｆ１の中心点Ｃｐ１と第２の光ファイバの傾斜端面Ｆ２の中心点Ｃｐ２との間に位置するロッドレンズ１００の中心においては、一方の光ファイバのコア１から出射され光ファイバ及びロッドレンズ１００の側面により収束された光ビームの径は、他方の光ファイバのコア１に入射する際の径より大きくても構わないように思われるが、光ビームに対する、光ファイバ側面による収束効果とロッドレンズ側面による収束効果とは、同時に作用しないため、結合効率を１にするためには、上記したように、ロッドレンズ１００の中心において、一方の光ファイバのコア１から出射され光ファイバ及びロッドレンズ１００の側面により収束された光ビームの径が、出射された際の径と同じになっていることが必要である。但し、結合効率が１に近い値で十分であるような場合には、他方の光ファイバのコア１に入射する光ビームの径が、一方の光ファイバのコア１から出射された際の径に略等しくなるように、上記第１の光ファイバＯｆ１とロッドレンズ１００との間隔、及びロッドレンズ１００と第２の光ファイバＯｆ２との間隔を設定してもよい。
【００７２】
次に、以上のように構成された光導波路の動作を図６を用いて説明する。
第１の光ファイバＯｆ１の他端に所定の波長λの光ビームを入射せしめると、入射した光ビームは、第１の光ファイバＯｆ１の中心部を中心軸Ａｘ１に沿ってスポットサイズω_A で進行し、第１の光ファイバＯｆ１の傾斜端面Ｆ１の中心点Ｃｐ１で該傾斜端面Ｆ１の中心軸Ａｘ４に対し４５°の角度で反射し、第１の光ファイバ／第２の光ファイバ直交軸Ａｘ３に沿って第１の光ファイバＯｆ１の側面，ロッドレンズ１００，及び第２の光ファイバＯｆ２の側面を通過し、第２の光ファイバＯｆ２の傾斜端面Ｆ２で該傾斜端面Ｆ２の中心軸Ａｘ５に対し４５°の角度で反射し、第２の光ファイバＯｆ２の中心部を中心軸Ａｘ２に沿ってスポットサイズω_B で進行し、該第２の光ファイバＯｆ２の他端から出射される。
【００７３】
この際に、第１の光ファイバの傾斜端面Ｆ１の中心点Ｃｐ１と第２の光ファイバの傾斜端面Ｆ２の中心点Ｃｐ２との間を通過する光ビームは、第１の光ファイバＯｆ１の側面とロッドレンズ１００の第１の光ファイバＯｆ１に対向する側面とによる収束効果と、第２の光ファイバＯｆ２の側面とロッドレンズ１００の第２の光ファイバＯｆ２に対向する側面とによる収束効果とを受け、第１の光ファイバの傾斜端面Ｆ１で反射された光ビームは、全て、第２の光ファイバの傾斜端面Ｆ２で反射された後、該第２の光ファイバＯｆ２のコア１に入射する。従って、両光ファイバＯｆ１，Ｏｆ２間の結合効率が１となる。
【００７４】
また、第２の光ファイバＯｆ２の他端に所定の波長λの光ビームを入射せしめると、入射した光ビームは、上記と全く逆の経路を辿り、上記と同様にして結合効率１でもって第２の光ファイバＯｆ２から第１の光ファイバＯｆ１に伝搬し、該第１の光ファイバＯｆ１の他端から出射される。
【００７５】
以上のように、本実施の形態２の光導波路によれば、一方の光ファイバに入射せしめた光ビームが、他方の光ファイバに結合効率１でもって伝搬され、かつ双方の光ファイバが、第１の光ファイバ／第２の光ファイバ直交軸Ａｘ３方向から見て、互いの傾斜端面が重なりかつ互いに０度の角度でもってに交差する（重なる）ように配置されているため、光配線を高結合効率でもってＵ字状に引き回すことが可能となる。
【００７６】
実施の形態３．
図７は本発明の実施の形態３による光導波路の構成を示す図であり、図７(a) は斜視図、図７(b) は図７(a) のＡ矢示図、図７(c) は図７(a) のＢ矢示図である。図において、図６と同一符号は同一又は相当する部分を示し、本実施の形態３による光導波路は、第２の光ファイバＯｆ２の中心軸Ａｘ２が、第１の光ファイバ／第２の光ファイバ直交軸Ａｘ３方向から見て第１の光ファイバの中心軸Ａｘ１に対して１８０度の交差角を有するよう配置されている点が実施の形態２と異なっているものである。
【００７７】
このように構成された光導波路は、第１の光ファイバＯｆ１とロッドレンズ１００との位置関係、及びロッドレンズ１００と第２の光ファイバＯｆ２との位置関係が実施の形態１の第１の光ファイバＯｆ１と第２の光ファイバＯｆ２との位置関係と同じになる。従って、第１の光ファイバＯｆ１とロッドレンズ１００との間隔、及びロッドレンズ１００と第２の光ファイバＯｆ２との間隔を、実施の形態１の光ファイバ間隔ｄと同様に設定することにより、第１の光ファイバＯｆ１とロッドレンズ１００との間、及びロッドレンズ１００と第２の光ファイバＯｆ２との間にて、光ビームを結合効率１でもって伝搬せしめることができる。
【００７８】
次に、以上のように構成された光導波路では、第１の光ファイバＯｆ１の他端に所定の波長λの光ビームを入射せしめると、入射した光ビームは、第１の光ファイバＯｆ１の中心部を中心軸Ａｘ１に沿ってスポットサイズω_A で進行し、第１の光ファイバＯｆ１の傾斜端面Ｆ１の中心点Ｃｐ１で該傾斜端面Ｆ１の中心軸Ａｘ４に対し４５°の角度で反射し、第１の光ファイバ／第２の光ファイバ直交軸Ａｘ３に沿って第１の光ファイバＯｆ１の側面，ロッドレンズ１００，及び第２の光ファイバＯｆ２の側面を通過し、第２の光ファイバＯｆ２の傾斜端面Ｆ２で該傾斜端面Ｆ２の中心軸Ａｘ５に対し４５°の角度で反射し、第２の光ファイバＯｆ２の中心部を中心軸Ａｘ２に沿ってスポットサイズω_B で進行し、該第２の光ファイバＯｆ２の他端から出射される。
【００７９】
この際に、第１の光ファイバの傾斜端面Ｆ１の中心点Ｃｐ１と第２の光ファイバの傾斜端面Ｆ２の中心点Ｃｐ２との間を通過する光ビームは、第１の光ファイバＯｆ１の側面とロッドレンズ１００の第１の光ファイバＯｆ１に対向する側面とによる収束効果と、第２の光ファイバＯｆ２の側面とロッドレンズ１００の第２の光ファイバＯｆ２に対向する側面とによる収束効果とを受け、第１の光ファイバＯｆ１の傾斜端面Ｆ１で反射された光ビームは、全て、第２の光ファイバの傾斜端面Ｆ２で反射された後、該第２の光ファイバＯｆ２のコア１に入射する。従って、両光ファイバＯｆ１，Ｏｆ２間の結合効率が１となる。
【００８０】
また、第２の光ファイバＯｆ２の他端に所定の波長λの光ビームを入射せしめると、入射した光ビームは、上記と全く逆の経路を辿り、上記と同様にして結合効率１でもって第２の光ファイバＯｆ２から第１の光ファイバＯｆ１に伝搬し、該第１の光ファイバＯｆ１の他端から出射される。
【００８１】
以上のように、本実施の形態３の光導波路によれば、一方の光ファイバに入射せしめた光ビームが、他方の光ファイバに結合効率１でもって伝搬され、かつ双方の光ファイバが、第１の光ファイバ／第２の光ファイバ直交軸Ａｘ３方向から見て、互いの傾斜端面が重なりかつ互いに１８０度の角度でもって交差するように配置されているため、光配線を高結合効率でもってＳ字状に引き回すことが可能となる。
【００８２】
実施の形態４．
図８は本発明の実施の形態４による光導波路の構成を示す図であり、図８(a) は斜視図、図８(b) は図８(a) のＡ矢示図、図８(c) は図８(a) のＢ矢示図である。図において、図６と同一符号は同一又は相当する部分を示し、本実施の形態４による光導波路は、ロッドレンズ１００が、第１，第２の光ファイバＯｆ１，Ｏｆ２と同一の構造を有する光ファイバで構成されている点が実施の形態２と異なっているものである。
【００８３】
このように構成された光導波路では、第１の光ファイバＯｆ１の他端に所定の波長λの光ビームを入射せしめると、入射した光ビームは、第１の光ファイバＯｆ１の中心部を中心軸Ａｘ１に沿って進行し、第１の光ファイバＯｆ１の傾斜端面Ｆ１の中心点Ｃｐ１で該傾斜端面Ｆ１の中心軸Ａｘ４に対し４５°の角度で反射し、第１の光ファイバ／第２の光ファイバ直交軸Ａｘ３に沿って第１の光ファイバＯｆ１の側面，ロッドレンズ１００のコア１，及び第２の光ファイバＯｆ２の側面を通過し、第２の光ファイバＯｆ２の傾斜端面Ｆ２で該傾斜端面Ｆ２の中心軸Ａｘ５に対し４５°の角度で反射し、第２の光ファイバＯｆ２の中心部を中心軸Ａｘ２に沿って進行し、該第２の光ファイバＯｆ２の他端から出射される。
【００８４】
この際に、第１の光ファイバの傾斜端面Ｆ１の中心点Ｃｐ１と第２の光ファイバの傾斜端面Ｆ２の中心点Ｃｐ２との間を通過する光ビームは、実施の形態２の場合と同様に、第１の光ファイバＯｆ１，ロッドレンズ１００、及び第２の光ファイバＯｆ２の側面による収束効果を受けて、結合効率１でもって伝搬する。
【００８５】
また、第２の光ファイバＯｆ２の他端に所定の波長λの光ビームを入射せしめると、入射した光ビームは、上記と全く逆の経路を辿り、上記と同様にして結合効率１でもって第２の光ファイバＯｆ２から第１の光ファイバＯｆ１に伝搬し、該第１の光ファイバＯｆ１の他端から出射される。
【００８６】
従って、本実施の形態４の光導波路によれば、ロッドレンズ１００として光ファイバを用いて、光配線を高結合効率でＵ字状に引き回すことができる。
【００８７】
また、ロッドレンズとしての光ファイバ１００のコア１に、第１の光ファイバＯｆ１と第２の光ファイバＯｆ２との間を伝搬する光ビームが当たると、該コア１が励起状態となるため、この励起により発生するレーザ光を取り出すことにより、本実施の形態４による光導波路をレーザとして用いることができる。
【００８８】
実施の形態５．
図９は本発明の実施の形態５による光導波路の構成を示す図であり、図９(a) は斜視図、図９(b) は図９(a) のＡ矢示図、図９(c) は図９(a) のＢ矢示図である。図において、図７と同一符号は同一又は相当する部分を示し、本実施の形態５による光導波路は、ロッドレンズ１００が、第１，第２の光ファイバＯｆ１，Ｏｆ２と同一の構造を有する光ファイバで構成されている点が実施の形態３と異なっているものである。
【００８９】
このように構成された光導波路では、第１の光ファイバＯｆ１の他端に所定の波長λの光ビームを入射せしめると、入射した光ビームは、第１の光ファイバＯｆ１の中心部を中心軸Ａｘ１に沿って進行し、第１の光ファイバＯｆ１の傾斜端面Ｆ１の中心点Ｃｐ１で該傾斜端面Ｆ１の中心軸Ａｘ４に対し４５°の角度で反射し、第１の光ファイバ／第２の光ファイバ直交軸Ａｘ３に沿って第１の光ファイバＯｆ１の側面，ロッドレンズ１００のコア１，及び第２の光ファイバＯｆ２の側面を通過し、第２の光ファイバＯｆ２の傾斜端面Ｆ２で該傾斜端面Ｆ２の中心軸Ａｘ５に対し４５°の角度で反射し、第２の光ファイバＯｆ２の中心部を中心軸Ａｘ２に沿って進行し、該第２の光ファイバＯｆ２の他端から出射される。
【００９０】
この際に、第１の光ファイバの傾斜端面Ｆ１の中心点Ｃｐ１と第２の光ファイバの傾斜端面Ｆ２の中心点Ｃｐ２との間を通過する光ビームは、実施の形態３の場合と同様に、第１の光ファイバＯｆ１，ロッドレンズ１００、及び第２の光ファイバＯｆ２の側面による収束効果を受けて、結合効率１でもって伝搬する。
【００９１】
また、第２の光ファイバＯｆ２の他端に所定の波長λの光ビームを入射せしめると、入射した光ビームは、上記と全く逆の経路を辿り、上記と同様にして結合効率１でもって第２の光ファイバＯｆ２から第１の光ファイバＯｆ１に伝搬し、該第１の光ファイバＯｆ１の他端から出射される。
【００９２】
従って、本実施の形態５の光導波路によれば、ロッドレンズ１００として光ファイバを用いて、光配線を高結合効率でＳ字状に引き回すことができる。
【００９３】
また、ロッドレンズとしての光ファイバ１００のコア１に、第１の光ファイバＯｆ１と第２の光ファイバＯｆ２との間を伝搬する光ビームが当たると、該コア１が励起状態となるため、この励起により発生するレーザ光を取り出すことにより、本実施の形態５による光導波路をレーザとして用いることができる。
【００９４】
実施の形態６．
図１０は本発明の実施の形態６による光導波路における光ファイバの傾斜端面の構造を示す側面図であり、図において、図１と同一符号は同一又は相当する部分を示す。本実施の形態６は、第１の光ファイバＯｆ１の傾斜端面Ｆ１，及び第２の光ファイバＯｆ２の傾斜端面Ｆ２に金属ミラー３が形成されている点が実施の形態１と異なっているものである。
【００９５】
上記金属ミラー３は、実施の形態１で述べた方法により鏡面とした傾斜端面Ｆ１，Ｆ２に、例えば、アルミニウム，銀等の金属を層状に蒸着することにより形成される。
【００９６】
このように構成された光導波路では、傾斜端面Ｆ１，Ｆ２に入射する光ビームは金属ミラー３の金属層の表面で反射される。このため、光ファイバＯｆ１，Ｏｆ２の屈折率が小さいために屈折率の相違によっては傾斜端面Ｆ１，Ｆ２における全反射条件を満たすようにすることができない場合でも、該傾斜端面Ｆ１，Ｆ２における全反射条件を満たすようにすることができる。また、グースヘンシェンシフトを考慮する必要がないため、光ファイバＯｆ１，Ｏｆ２の位置を容易に設定することができる。
【００９７】
なお、実施の形態２〜５においても、上記と同様にして、第１の光ファイバＯｆ１の傾斜端面Ｆ１，及び第２の光ファイバＯｆ２の傾斜端面Ｆ２に金属ミラー３を形成することができ、上記と同様の効果を得ることができる。
【００９８】
実施の形態７．
図１１は本発明の実施の形態７による光導波路における光ファイバの傾斜端面の構造を示す側面図であり、図において、図１と同一符号は同一又は相当する部分を示す。本実施の形態７は、第１の光ファイバＯｆ１の傾斜端面Ｆ１，及び第２の光ファイバＯｆ２の傾斜端面Ｆ２に多層膜ミラー４が形成されている点が実施の形態１と異なっているものである。
【００９９】
多層膜ミラー４は、例えば、ＴｉＯ₂ ／ＳｉＯ₂ の交互層からなり、厚み１μｍの層が５〜１０層積層されてなる。
【０１００】
また、多層膜ミラー４は、実施の形態１で述べた方法により、光ファイバＯｆ１，Ｏｆ２に鏡面からなる傾斜端面Ｆ１，Ｆ２を形成した後、該傾斜端面Ｆ１，Ｆ２に、ＴｉＯ₂ とＳｉＯ₂ とを交互に層状に蒸着することにより形成される。
【０１０１】
このように構成された光導波路では、傾斜端面Ｆ１，Ｆ２に、該傾斜端面Ｆ１，Ｆ２の中心軸Ａｘ４，Ａｘ５に４５°の角度で光ビームが入射すると、入射した光ビームは、光ファイバＯｆ１，Ｏｆ２と多層膜ミラー４との界面、及び多層膜ミラー４内の各層間の界面で、ある界面に入射する光ビームのうち、一部が反射され、他は透過して次の界面に入射するようにして逐次反射されていき、最終的にそのほとんどが反射される。このため、光ファイバＯｆ１，Ｏｆ２の屈折率が小さいために傾斜端面Ｆ１，Ｆ２における全反射条件を満たすようにすることができない場合でも、該傾斜端面Ｆ１，Ｆ２における全反射条件を満たすようにすることができる。
【０１０２】
なお、実施の形態２〜５においても、上記と同様にして、第１の光ファイバＯｆ１の傾斜端面Ｆ１，及び第２の光ファイバＯｆ２の傾斜端面Ｆ２に多層膜ミラー４を形成することができ、上記と同様の効果を得ることができる。
【０１０３】
実施の形態８．
本発明の実施の形態８による光導波路は、図１１の実施の形態７による光導波路において、第１，第２の光ファイバＯｆ１，Ｏｆ２の傾斜端面Ｆ１，Ｆ２に形成された多層膜ミラー４のうちのいずれかを、波長に対し選択的に入射光を全反射するものであるようにした点が実施の形態１と異なっているものである。多層膜ミラー４の反射特性に波長選択性を持たすには、該多層膜ミラー４を構成する各層の誘電体の屈折率と厚みとを、反射特性について所望の波長選択性を示すように選択すればよい。
【０１０４】
このように構成された光導波路では、一方の光ファイバに、特定の値以上又は特定の値以下の波長の光ビームを入射せしめたときのみ、該入射せしめた光ビームが、上記波長選択性を有する多層膜ミラー４が形成された傾斜端面で反射されて、他の光ファイバに伝達されるため、波長選択フィルタとして用いることができる。
【０１０５】
なお、上記の説明では、第１，第２の光ファイバＯｆ１，Ｏｆ２の傾斜端面Ｆ１，Ｆ２に形成された多層膜ミラー４のうちの一方を、反射特性が波長選択性を有するようにしているが、双方を、反射特性について同じ波長選択性を有するようにしてもよい。
【０１０６】
実施の形態９．
図１２は本発明の実施の形態９による光導波路の構成を示す斜視図であり、図において、図１及び図１１と同一符号は同一又は相当する部分を示す。本実施の形態９は、第１の光ファイバの傾斜端面Ｆ１に形成された第１の多層膜ミラー４ａと、第２の光ファイバの傾斜端面Ｆ２に形成された第２の多層膜ミラー４ｂとが、反射特性について互いに異なる波長選択性を有しているようにした点が実施の形態８と異なっているものである。
【０１０７】
例えば、第１の多層膜ミラー４ａは、第１の波長λ1 以上の波長の入射光を全反射するものとされ、第２の多層膜ミラー４ｂは、第１の波長λ1 より大きい第２の波長λ2 以下の波長の入射光を全反射するものとされる。
【０１０８】
このように構成された光導波路では、一方の光ファイバに、第１の波長λ1 より短い波長を有する光ビームを入射せしめると、該入射せしめた光ビームは、第１の多層膜ミラー４ａを通過してしまい、他の光ファイバには伝達されない。また、一方の光ファイバに、第２の波長λ2 より長い波長を有する光ビームを入射せしめると、該入射せしめた光ビームは、第２の多層膜ミラー４ｂを通過してしまい、他の光ファイバには伝達されない。そして、第１の波長λ1 から第２の波長λ2 までの帯域の波長を有する光ビームを入射せしめると、該入射せしめた光ビームは、第１の多層膜ミラー４ａ及び第２の多層膜ミラー４ｂで全反射されて、他の光ファイバに伝達される。このため、帯域通過フィルタとして用いることができる。また、この光導波路において、他方の光ファイバから出射される光ビームに代えて、第１の多層膜ミラー４ａ，及び第２の多層膜ミラー４ｂから出射される光ビームを出力とすることにより、この光導波路を帯域阻止フィルタとして用いることができる。
【０１０９】
実施の形態１０．
図１３は本発明の実施の形態１０による光導波路の構成を示す図であり、図１３(a) は斜視図、図１３(b) は図１３(a) のＡ矢示図、図１３(c) は図１３(a) のＢ矢示図である。図において、図１と同一符号は同一又は相当する部分を示し、本実施の形態１０による光導波路は、第１，第２の光ファイバＯｆ１，Ｏｆ２に加えて、該第１，第２の光ファイバＯｆ１，Ｏｆ２と同一の構造を有し、かつその一端に中心軸Ａｘ７に対し４５度傾斜した傾斜端面Ｆ３を有する第３の光ファイバＯｆ３をさらに有し、該第３の光ファイバＯｆ３を、該第３の光ファイバＯｆ３の中心軸Ａｘ７が、第１の光ファイバの中心軸Ａｘ１に一致し、かつ第３の光ファイバの傾斜端面Ｆ３が、第１の光ファイバの傾斜端面Ｆ１に対し略平行でかつ所定の間隔Ｓを有するよう配置してなる点が、実施の形態１と異なるものである。また、Ｐ１〜Ｐ３は、第１〜第３の光ファイバＯｆ１〜Ｏｆ３の他端である第１〜第３のポートを示している。
【０１１０】
次に、このように構成された光導波路の動作を説明する。
まず、光ビームを第１のポートＰ１から入射せしめると、入射した光ビームは、傾斜端面Ｆ１及び傾斜端面Ｆ３の間隔Ｓに応じた割合で、一部が傾斜端面Ｆ１及び傾斜端面Ｆ３を通過して第３の光ファイバＯｆ３に入射し、第３のポートＰ３から出射され、他は傾斜端面Ｆ１で反射して第２の光ファイバＯｆ２を通り、第２のポートＰ２から出射される。その結果、光分波器として機能する。
【０１１１】
一方、第２のポートＰ２，及び第３のポートＰ３から光ビームをそれぞれ入射せしめると、入射した２つの光ビームは第１の光ファイバの傾斜端面Ｆ１で合波されて第１の光ファイバに入射し、第１のポートＰ１から出射される。その結果、光合波器として機能する。
【０１１２】
従って、本実施の形態１０によれば、光ビームを合分波することができ、かつ光配線を高結合効率でＴ字状に引き回すことができる光導波路を提供することができる。
【０１１３】
実施の形態１１．
図１４は本発明の実施の形態１１による光導波路の構成を示す図であり、図１４(a) は斜視図、図１４(b) は図１４(a) のＡ矢示図、図１４(c) は図１４(a) のＢ矢示図である。
【０１１４】
図において、図１と同一符号は同一又は相当する部分を示し、本実施の形態１０による光導波路は、以下の点で実施の形態１０による光導波路と異なるものである。すなわち、第１〜第３の光ファイバＯｆ１〜Ｏｆ３に加えて、該第１〜第３の光ファイバＯｆ１〜Ｏｆ３と同一の構造を有し、かつその一端に中心軸Ａｘ８に対し４５度傾斜した傾斜端面Ｆ４を有する第４の光ファイバＯｆ４をさらに有し、第３の光ファイバＯｆ３に対し、第４の光ファイバＯｆ４を、該第４の光ファイバＯｆ４の傾斜端面Ｆ４の中心Ｃｐ４が、第３の光ファイバＯｆ３の傾斜端面Ｆ３の中心Ｃｐ３にて該傾斜端面Ｆ３の中心軸Ａｘ１０を挟むようにして該第３の光ファイバＯｆ３の中心軸Ａｘ７に直交する第３の光ファイバ／第４の光ファイバ直交軸Ａｘ９上に位置し、第４の光ファイバＯｆ４の中心軸Ａｘ８が、該第４の光ファイバＯｆ４の傾斜端面Ｆ４の中心軸Ａｘ１１を挟むようにして第３の光ファイバ／第４の光ファイバ直交軸Ａｘ９に直交するとともに該第３の光ファイバ／第４の光ファイバ直交軸Ａｘ９方向から見て第３の光ファイバＯｆ３の中心軸Ａｘ７に対し９０度の交差角を有し、第３の光ファイバＯｆ３の傾斜端面Ｆ３と第４の光ファイバＯｆ４の傾斜端面Ｆ４とが、第３の光ファイバ／第４の光ファイバ直交軸Ａｘ９方向から見て互いに反対の方向を向き、かつ、第４の光ファイバＯｆ４と第３の光ファイバＯｆ３との間隔が、実施の形態１で述べた結合効率ηが１となる条件を満たす値（図示例ではゼロ）となるように配置されている。また、Ｐ４は、第４の光ファイバＯｆ４の他端である第４のポートである。
【０１１５】
ここで、図１４(c) に示すように、第１の光ファイバの傾斜端面Ｆ１と第３の光ファイバの傾斜端面Ｆ３とは、所定の間隔Ｓを有しているため、第１の光ファイバ／第２の光ファイバ直交軸Ａｘ３と第３の光ファイバ／第４の光ファイバ直交軸Ａｘ９とは一致しないが、上記所定の間隔Ｓは第１〜第４の光ファイバＯｆ１〜Ｏｆ４のスポットサイズに比べると微小であるため、傾斜端面Ｆ１〜Ｆ４における光ビームの反射又は透過を解析する場合には、第１の光ファイバ／第２の光ファイバ直交軸Ａｘ３と第３の光ファイバ／第４の光ファイバ直交軸Ａｘ９は一致するものとみなすことができる。
【０１１６】
次に、以上のように構成された光導波路の動作を説明する。
まず、第１のポートＰ１から光ビームを入射せしめると、入射した光ビームは、傾斜端面Ｆ１及び傾斜端面Ｆ３で分配されて、第２のポートＰ２と第３のポートＰ３から出力される。また、第２のポートＰ２から光ビームを入射せしめると、入射した光ビームは、傾斜端面Ｆ１及び傾斜端面Ｆ３で分配されて、第１のポートＰ１と第４のポートＰ４から出力される。以下同様に、第３のポートＰ３から入射せしめた光ビームは、傾斜端面Ｆ３及び傾斜端面Ｆ１で分配されて、第４のポートＰ４と第１のポートＰ１から出力され、第４のポートＰ４から入射せしめた光ビームは、傾斜端面Ｆ３及び傾斜端面Ｆ１で分配されて、第３のポートＰ３と第２のポートＰ２から出力される。
【０１１７】
従って、本実施の形態１１による光導波路によれば、４つのポートＰ１〜Ｐ４のいずれを入力ポートとして用いても、分波することができる。
【０１１８】
実施の形態１２．
図１５は本発明の実施の形態１２による光導波路の構成を示す図であり、図１５(a) は斜視図、図１５(b) は図１５(a) のＡ矢示図、図１５(c) は図１５(a) のＢ矢示図である。図において、図６と同一符号は同一又は相当する部分を示し、本実施の形態１２による光導波路は、第１，第２の光ファイバＯｆ１，Ｏｆ２、及びロッドレンズ１００に加えて、該第１，第２の光ファイバＯｆ１，Ｏｆ２と同一の構造を有し、かつその一端に中心軸Ａｘ７に対し４５°傾斜した傾斜端面Ｆ３を有する第３の光ファイバＯｆ３をさらに有し、該第３の光ファイバＯｆ３を、該第３の光ファイバＯｆ３の中心軸Ａｘ７が、第１の光ファイバの中心軸Ａｘ１に一致し、かつ第３の光ファイバの傾斜端面Ｆ３が、第１の光ファイバの傾斜端面Ｆ１に対し略平行でかつ所定の間隔Ｓを有するよう配置してなる点が、実施の形態２による光導波路と異なるものである。また、Ｐ１〜Ｐ３は、第１〜第３の光ファイバＯｆ１〜Ｏｆ３の他端である第１〜第３のポートを示している。
【０１１９】
次に、このように構成された光導波路の動作を説明する。
まず、光ビームを第１のポートＰ１から入射せしめると、入射した光ビームは、傾斜端面Ｆ１及び傾斜端面Ｆ３の間隔Ｓに応じた割合で、一部が傾斜端面Ｆ１及び傾斜端面Ｆ３を通過して第３の光ファイバＯｆ３に入射し、第３のポートＰ３から出射され、他は傾斜端面Ｆ１で反射して第２の光ファイバＯｆ２を通り、第２のポートＰ２から出射される。その結果、光分波器として機能する。
【０１２０】
一方、第２のポートＰ２，及び第３のポートＰ３から光ビームをそれぞれ入射せしめると、入射した２つの光ビームは第１の光ファイバＯｆ１の傾斜端面Ｆ１で合波されて第１の光ファイバＯｆ１に入射し、第１のポートＰ１から出射される。その結果、光合波器として機能する。
【０１２１】
従って、本実施の形態１２によれば、光ビームを合分波することができ、かつ光配線を高結合効率でもって同一平面内でｈ字状に引き回すことができる光導波路を提供することができる。
【０１２２】
実施の形態１３．
図１６は本発明の実施の形態１３による光導波路の構成を示す図であり、図１６(a) は斜視図、図１６(b) は図１６(a) のＡ矢示図、図１６(c) は図１６(a) のＢ矢示図である。図において、図７と同一符号は同一又は相当する部分を示し、本実施の形態１３による光導波路は、第１，第２の光ファイバＯｆ１，Ｏｆ２、及びロッドレンズ１００に加えて、該第１，第２の光ファイバＯｆ１，Ｏｆ２と同一の構造を有し、かつその一端に中心軸Ａｘ７に対し４５°傾斜した傾斜端面Ｆ３を有する第３の光ファイバＯｆ３をさらに有し、該第３の光ファイバＯｆ３を、該第３の光ファイバＯｆ３の中心軸Ａｘ７が、第１の光ファイバの中心軸Ａｘ１に一致し、かつ第３の光ファイバの傾斜端面Ｆ３が、第１の光ファイバＯｆ１の傾斜端面Ｆ１に対し略平行でかつ所定の間隔Ｓを有するよう配置してなる点が、実施の形態３による光導波路と異なるものである。また、Ｐ１〜Ｐ３は、第１〜第３の光ファイバＯｆ１〜Ｏｆ３の他端である第１〜第３のポートを示している。
【０１２３】
このように構成された光導波路では、光ビームを第１のポートＰ１から入射せしめると、入射した光ビームは、傾斜端面Ｆ１及び傾斜端面Ｆ３の間隔Ｓに応じた割合で、一部が傾斜端面Ｆ１及び傾斜端面Ｆ３を通過して第３の光ファイバＯｆ３に入射し、第３のポートＰ３から出射され、他は傾斜端面Ｆ１で反射して第２の光ファイバＯｆ２を通り、第２のポートＰ２から出射される。一方、第２のポートＰ２，及び第３のポートＰ３から光ビームをそれぞれ入射せしめると、入射した２つの光ビームは第１の光ファイバの傾斜端面Ｆ１で合波されて第１の光ファイバＯｆ１に入射し、第１のポートＰ１から出射される。
【０１２４】
従って、本実施の形態１３によれば、光ビームを合分波することができ、かつ光配線を高結合効率でもって同一平面内でｈ字状に引き回すことができる光導波路を提供することができる。
【０１２５】
実施の形態１４．
図１７は本発明の実施の形態１４による光導波路における光ファイバの傾斜端面の位置を示す図である。
図において、図１と同一符号は同一又は相当する部分を示し、本実施の形態１４は、以下の点が実施の形態１と異なっているものである。
すなわち、Ｃｐ１′は、第１の光ファイバＯｆ１の中心を伝搬する光に対するグースヘンシェンシフトＺ_GHによる見かけ上の反射点、Ｆ１′は、該見かけ上の反射点Ｃｐ１′をその中心に有し、かつ第１の光ファイバＯｆ１の傾斜端面Ｆ１に平行な仮想傾斜端面、Ａｘ５′は該仮想傾斜端面Ｆ１′の中心軸を示している。本実施の形態１４では、第１の光ファイバＯｆ１は、該仮想傾斜端面Ｆ１′が、図１の光導波路における第１の光ファイバＯｆ１の傾斜端面Ｆ１が存在する位置に位置するように、中心軸Ａｘ１方向に距離Ｌだけずらせて配置されている。
【０１２６】
また、第２の光ファイバＯｆ２も、第１の光ファイバＯｆ１と同様に、該第２の光ファイバＯｆ２の仮想傾斜端面が、図１の光導波路における第２の光ファイバＯｆ２の傾斜端面Ｆ２が存在する位置に位置するように、中心軸Ａｘ２方向に距離Ｌだけずらせて配置されている（図示せず）。
【０１２７】
次に、このように構成された光導波路では、光ビームが第１の光ファイバＯｆ１と第２の光ファイバＯｆ２との接続部を伝搬する際に、第１の光ファイバの傾斜端面Ｆ１，及び第２の光ファイバの傾斜端面Ｆ２におけるグースヘンシェンシフトによる反射点のズレが補正されるため、該反射点のズレに伴って結合効率が低下するのを防止することができる。
【０１２８】
なお、実施の形態２〜５においても、上記と同様に構成することにより、上記と同様の効果を得ることができる。
【０１２９】
実施の形態１５．
図１８は本発明の実施の形態１５による光合分波器の構成を示す図であり、図１８(a) は正面図、図１８(b) は図１８(a) のＣ矢示図である。図において、図１３と同一符号は同一又は相当する部分を示し、本実施の形態１５による光合分波器は、実施の形態１０による光導波路の第３の光ファイバＯｆ３を、該第３の光ファイバＯｆ３の中心軸Ａｘ７方向に移動可能なように構成したものである。
【０１３０】
このように構成された光合分波器では、第３の光ファイバの傾斜端面Ｆ３を、第１の光ファイバの傾斜端面Ｆ１から無限大の距離に位置させると、第１のポートＰ１から入射せしめた光ビームは、全て第２のポートＰ２に出力される。また、第３の光ファイバの傾斜端面Ｆ３を第１の光ファイバの傾斜端面Ｆ１に接触させると、第１のポートＰ１から入射せしめた光ビームは、全て第２のポートＰ２に出力される。そして、第３の光ファイバの傾斜端面Ｆ３を、第１の光ファイバの傾斜端面Ｆ１に対しある間隔Ｓを有するように位置させると、第１のポートＰ１から入射せしめた光ビームは、該間隔Ｓに応じた比率でもって一部が第２のポートＰ２に出力され、他が第３のポートＰ３に出力される。
【０１３１】
また、第３の光ファイバの傾斜端面Ｆ３を、第１の光ファイバの傾斜端面Ｆ１から無限大の距離に位置させて、第２のポートＰ２、及び第３のポートＰ３からそれぞれ光ビームを入射せしめると、第３のポートＰ３から入射せしめた光ビームは、全て、第３の光ファイバの傾斜端面Ｆ３で反射されてしまい、第２のポートＰ２から入射せしめた光ビームのみが、全て、第１のポートＰ１に出力される。また、第３の光ファイバの傾斜端面Ｆ３を、第１の光ファイバの傾斜端面Ｆ１に接触させて、第２のポートＰ２、及び 第３のポートＰ３からそれぞれ光ビームを入射せしめると、第２のポートＰ２から入射せしめた光ビームは、全て、第１の光ファイバの傾斜端面Ｆ１及び第３の光ファイバの傾斜端面Ｆ３を通過してしまい、第３のポートＰ２から入射せしめた光ビームのみが、全て、第１のポートＰ１に出力される。そして、第３の光ファイバの傾斜端面Ｆ３を、第１の光ファイバの傾斜端面Ｆ１に対しある間隔Ｓを有するように位置させて、第２のポートＰ２、及び第３のポートＰ３からそれぞれ光ビームを入射せしめると、該入射せしめた２つの光ビームは、該間隔Ｓに応じた比率でもって合成されて、第１のポートＰ３に出力される。
【０１３２】
なお、上記の説明では、第３の光ファイバの傾斜端面Ｆ３と第１の光ファイバの傾斜端面Ｆ１との間隔Ｓを変化させるのに、第３の光ファイバＯｆ３を移動自在としたが、第１，第２の光ファイバＯｆ１，Ｏｆ２を移動自在としてもよい。
【０１３３】
以上のように、本実施の形態１５の光合分波器によれば、第３の光ファイバの傾斜端面Ｆ３と第１の光ファイバの傾斜端面Ｆ１との間隔Ｓを変化させることにより、該間隔Ｓに応じて、第１のポートＰ１から入射せしめた光ビームが第２のポートＰ２，及び第３のポートＰ３へ出力される際の分配比、及び第２のポートＰ２，及び第３のポートＰ３からそれぞれ入射せしめた光ビームが第１のポートＰ１へ出力される際の合成比が変化するので、可変光合分波器として用いることができる。
【０１３４】
実施の形態１６．
図１９は本発明の実施の形態１６による光合分波器の構成を示す図である。図において、図１３と同一符号は同一又は相当する部分を示し、本実施の形態１６による光合分波器は、実施の形態１０による光導波路の第１の光ファイバＯｆ１の傾斜端面Ｆ１と第１の光ファイバＯｆ１の傾斜端面Ｆ３との隙間に波長選択フィルタ５を介挿したものである。
【０１３５】
上記波長選択フィルタ５は、例えば、ある波長λ0 以上の波長の光を透過し、該波長λ0 未満の波長の光を反射するものとされる。
【０１３６】
このように構成された光合分波器では、第１のポートＰ１から、上記波長λ0 より小さい波長λ1 を有する光と上記波長λ0 より大きい波長λ2 を有する光とからなる光ビームを入射せしめると、該入射せしめた光ビームのうち、波長λ1 を有する光は波長選択フィルタ５で反射されて第２のポートＰ２に出力され、波長λ2 を有する光は波長選択フィルタ５を透過して第３のポートＰ３に出力されるため、該入射せしめた光ビームは波長分割される。
【０１３７】
従って、本実施の形態１６によれば、波長分割可能な光合分波器を提供することができる。
【０１３８】
実施の形態１７．
本発明の実施の形態１７は、実施の形態１０の光導波路を複数平行に配置することにより、光パラレルバスとしたものである。
【０１３９】
図２０は本実施の形態１７による光パラレルバスの構成を示す図であって、図２０(a) は上面図、図２０(b) は図２０(a) のＥ矢示図である。図において、図１と同一符号は同一又は相当する部分を示し、Ｂｕは、第１の光パラレルバスＢｕ１と第２の光パラレルバスＢｕ２とからなる光パラレルバス、６は光ファイバ固定溝、７は基板である。
【０１４０】
第１の光パラレルバスＢｕ１は、同じ本数（本実施の形態１７ではそれぞれ４本）の第１の光ファイバＯｆ１，及び第３の光ファイバＯｆ３で構成され、これら第１の光ファイバＯｆ１，及び第３の光ファイバＯｆ３は、基板７の上面に複数平行に形成されたＶ字状の断面を有する光ファイバ固定溝６で保持されている。従って、第１の光ファイバの中心軸Ａｘ１，及び第３の光ファイバの中心軸Ａｘ７は、それぞれ、互いに平行で全て同一の平面内に位置している。そして、４本の第１の光ファイバＯｆ１は、各第１の光ファイバＯｆ１の中心軸Ａｘ１及び傾斜端面Ｆ１の中心軸を含む平面が全て上記平面に垂直となりかつ該各第１の光ファイバＯｆ１の傾斜端面Ｆ１が全て同じ方向（図では下方）を向き、かつ各第１の光ファイバの傾斜端面Ｆ１が該第１の光ファイバＯｆ１の配列方向から見て互い重ならないように配置され、４本の第３の光ファイバＯｆ３は、４本の第１の光ファイバＯｆ１に１対１で対応するようにして、該第３の光ファイバＯｆ３の中心軸Ａｘ７が、対応する第１の光ファイバＯｆ１の中心軸Ａｘ１に一致し、かつ該第３の光ファイバＯｆ３の傾斜端面Ｆ３が、対応する第１の光ファイバＯｆ１の傾斜端面Ｆ１に対し、所定の間隔で平行となるよう配置されている。
【０１４１】
第２の光パラレルバスＢｕ２は、４本の第２の光ファイバＯｆ２で構成され、これら４本の第２の光ファイバＯｆ２は、上記第１の光ファイバＯｆ１，及び第３の光ファイバＯｆ３と同様、基板（図示せず）により、互いに平行で中心軸Ａｘ２が全て同一平面内に位置するように保持されている。そして、４本の第２の光ファイバＯｆ２は、４本の第１の光ファイバＯｆ１に１対１で対応するようにして、各第２の光ファイバの傾斜端面Ｆ２の中心が、各第１の光ファイバの傾斜端面Ｆ１の中心にて該傾斜端面Ｆ１の中心軸を挟むようにして各第１の光ファイバの中心軸Ａｘ１に直交する各第１の光ファイバ／第２の光ファイバ直交軸上に位置し、各第２の光ファイバの中心軸Ａｘ２が、互いに平行で全て同一平面内に存在し、かつ各第２の光ファイバの傾斜端面Ｆ２の中心軸を挟むようにして各第１の光ファイバ／第２の光ファイバ直交軸に直交するとともに該各第１の光ファイバ／第２の光ファイバ直交軸方向から見て各第１の光ファイバの中心軸Ａｘ１に対し９０度の交差角を有し、各第１の光ファイバの傾斜端面Ｆ１と各第２の光ファイバの傾斜端面Ｆ２とが、各第１の光ファイバ／第２のファイバ直交軸方向から見て互いに反対の方向を向き、かつ各第２の光ファイバＯｆ２と各第１の光ファイバＯｆ１とが接するように配置されている。
【０１４２】
第１の光ファイバＯｆ１，第２の光ファイバＯｆ２，及び第３の光ファイバＯｆ３は、屈折率が、実施の形態１と同様に、各々の傾斜端面が全反射条件を満たすように選択され、パラメータαが、第１の光ファイバＯｆ１と第２の光ファイバＯｆ２とが接触するとき結合効率が１となるよう選択され、かつ第１の光ファイバの傾斜端面Ｆ１と第３の光ファイバの傾斜端面Ｆ３との所定の間隔が、該第１の光ファイバの傾斜端面Ｆ１における反射率が所定値（例えば０．５）となるよう選択される。
【０１４３】
以上のように構成された光パラレルバスでは、第１の光パラレルバスＢｕ１の任意の第１の光ファイバＯｆ１に光ビームを入射せしめると、該入射せしめた光ビームは、第１の光ファイバＯｆ１の傾斜端面Ｆ１で上記所定の反射率に応じた比率で第２の光ファイバＯｆ２に分配され、第１の光パラレルバスＢｕ１の任意の第３の光ファイバＯｆ３，及び該任意の第３の光ファイバＯｆ３に対応する第２の光パラレルバスＢｕ２の第３の光ファイバＯｆ３に光ビームをそれぞれ入射せしめると、該入射せしめた光ビームは、第１の光ファイバの傾斜端面Ｆ１で上記所定の反射率に基づいた比率で合波されて第１の光ファイバＯｆ１に出力される。
【０１４４】
以上のように、本実施の形態１７の光パラレルバスによれば、第１の光ファイバＯｆ１及び第３の光ファイバＯｆ３を複数平行に平面状に配列してなる第１の光パラレルバスＢｕ１と、第１の光ファイバＯｆ１と１対１で対応する第２の光ファイバＯｆ２を平行に平面状に配列してなる第２の光パラレルバスＢｕ２とは、その配列方向から見てその傾斜端面Ｆ１が重ならないように配置された各第１の光ファイバＯｆ１に対し、各第２の光ファイバＯｆ２が、第１，第２の光ファイバＯｆ１，Ｏｆ２の配列面に垂直な方向から見て、双方の傾斜端面Ｆ１，Ｆ２が重なるようにして互いに直角に交差し、各第３の光ファイバＯｆ３が所定の間隔を有して第１の光ファイバＯｆ１の延長上に位置するように接続されているので、各光パラレルバスＢｕ１，Ｂｕ２を構成する光ファイバＯｆ１，Ｏｆ３，Ｏｆ２を密接して配置することができるため、配線スペースを節約することができる。また、各第１の光ファイバＯｆ１と各第２の光ファイバＯｆ２とは、実施の形態１による光導波路を形成しているため、結合効率が１となり、高効率なものとなる。
【０１４５】
実施の形態１８．
本発明の実施の形態１８は、実施の形態１の光導波路をＥＯチップとＥＯボードとの接続部に用いた光電子集積装置を例示するものである。
【０１４６】
図２１は本実施の形態１８による光電子集積装置の構成を示す斜視図である。図において、図１と同一符号は同一又は相当する部分を示し、１０は、ＥＯチップ１１とＥＯボード１４からなる光電子集積装置である。
【０１４７】
ＥＯチップ１１は、内部に電子素子及び光素子を含む光電子回路を有しており、該ＥＯチップ１１の下面には、その基端が上記光電子回路と電気的に接続された複数本の電極ピン（チップ側接触用電極）１６と、その基端が上記光電子回路と光学的に接続され、その先端に傾斜端面Ｆ１を有し、かつ所定の長さを有する複数本（図では４本）の第１の光ファイバ（チップ側光接続手段）Ｏｆ１とが、下方に向け突設されている。さらに、ＥＯチップ１１の下面には、直方体形状を有する位置決め用凸部１８が突設されている。
【０１４８】
ＥＯボード１４は、上側に配置されたＥボード層１２と下側に配置されたＯボード層１３とからなり、該ＥＯボード１４の上面のＥＯチップ１１が装着される領域には、ＥＯチップ１１の位置決め用凸部１８，及び電極ピン１６に対応する位置に、それぞれ、位置決め用凹部１９，及び電極孔（ボード側接触用電極）１７が凹設され、ＥＯチップ１１の第１の光ファイバＯｆ１に対応する位置に、光ファイバ挿入孔１５が凹設されている。さらに、ＥＯボード１４の上面には、ＥＯチップ１１を固定するためのレバー２０が配設されている。
【０１４９】
位置決め用凹部１９は、ＥＯチップ１１の位置決め用凸部１８に嵌合する直方体形状を有している。
【０１５０】
電極孔１７は、ＥＯチップ１１の電極ピン１６に嵌合する形状を有し、内面に、Ｅボード層１２の電気配線と接続された電極が配設されている。
【０１５１】
光ファイバ挿入孔１５は、Ｅボード層１２を貫通し、Ｏボード層１３の厚みの中程に達する深さを有するように形成され、該光ファイバ挿入孔１５のＯボード層１３に形成された部分の内面には、その基端がＯボード層１３の光配線に接続され、その先端に傾斜端面Ｆ２を有し、かつ所定の長さを有する４本の第２の光ファイバ（ボード側光接続手段）Ｏｆ２が、水平方向に突設されている。
【０１５２】
４本の第２の光ファイバＯｆ２は、４本の第１の光ファイバＯｆ１に１対１で対応するよう設けられ、この１対１で対応する第２の光ファイバＯｆ２，及び第１の光ファイバＯｆ１の対は、ＥＯチップ１１がＥＯボード１４に装着されたとき、実施の形態１で述べた結合効率が１となる位置関係になるように配置されている。
【０１５３】
すなわち、第２の光ファイバＯｆ２，及び第１の光ファイバＯｆ１の各対は、ＥＯチップ１１がＥＯボード１４に装着されたとき、各第２の光ファイバＯｆ２の傾斜端面Ｆ２の中心が、各第１の光ファイバＯｆ１の傾斜端面Ｆ１の中心にて該傾斜端面Ｆ１の中心軸を挟むようにして各第１の光ファイバＯｆ１の中心軸に直交する各第１の光ファイバ／第２の光ファイバ直交軸上に位置し、各第２の光ファイバＯｆ２の中心軸が、各第２の光ファイバの傾斜端面Ｆ２の中心軸を挟むようにして上記各第１の光ファイバ／第２の光ファイバ直交軸に直交するとともに該各第１の光ファイバ／第２の光ファイバ直交軸方向から見て各第１の光ファイバの中心軸に対し９０度の交差角を有し、各第１の光ファイバの傾斜端面Ｆ１と各第２の光ファイバの傾斜端面Ｆ２とが、各第１の光ファイバ／第２のファイバ直交軸方向から見て互いに反対の方向を向き、かつ、各第２の光ファイバＯｆ２と各第１の光ファイバＯｆ２とが接触するように配置されている。
【０１５４】
また、第１の光ファイバＯｆ１，及び第２の光ファイバＯｆ２は、屈折率が、実施の形態１と同様に、各々の傾斜端面Ｆ１，Ｆ２が全反射条件を満たすよう選択され、パラメータαが、第１の光ファイバＯｆ１と第２の光ファイバＯｆ２とが接触するとき結合効率が１となるよう選択される。
【０１５５】
レバー２０は、先端に丸みを有する板状の押圧部２２と、該押圧部２２の先端の一部に突設された棒状の操作部２１と、押圧部２２の基部の両側面に突設された回転軸２３と、ＥＯボード１４の上面に配設され、押圧部２２の回転軸２３を回動自在に保持する支持部材２４とからなり、該支持部材２４は、押圧部材２２が水平状態となったとき、該押圧部材２２の先端で、ＥＯボード１４に装着されたＥＯチップ１１が押圧され、それにより、ＥＯチップ１１の位置決め用凸部１８が、ＥＯボード１４の位置決め用凹部１９の該押圧方向（図の矢印方向）の内壁に押しつけられるような位置に設置されている。また、ＥＯボード１４の各電極孔１７，及び第２の光ファイバＯｆ２の位置は、上記のようにＥＯチップ１１の位置決め用凸部１８がＥＯボード１４の位置決め用凹部１９の押圧方向の内壁に押しつけられたとき、ＥＯチップ１１の各電極ピン１６，及び各第１の光ファイバＯｆ１が、それぞれ、該各電極孔１７の該押圧方向の側壁，及び該第２の光ファイバＯｆ２の側面に、丁度、接触するように設定されている。
【０１５６】
次に、以上のように構成された光電子集積装置１０の動作を説明する。
まず、ＥＯチップ１１のＥＯボード１４に装着するには、操作部２１を引いてレバー２０を垂直状態に起こす。次いで、ＥＯチップ１１の位置決め用凸部１８，電極ピン１６，及び第１の光ファイバＯｆ１を、それぞれ、ＥＯボード１４の位置決め用凹部１９，電極孔１７，及び光ファイバ挿入孔１５にそれぞれ嵌挿するようにして、ＥＯチップ１１をＥＯボード１４に取り付ける。次いで、操作部２１を押して、レバー２０を水平状態に倒す。すると、ＥＯチップ１１は、レバー２０の押圧部２２で矢印方向に押圧され、位置決め用凸部１８が、ＥＯボード１４の位置決め用凹部１９の該押圧方向の内壁に押しつけられて固定されるとともに、電極ピン１６，及び第１の光ファイバＯｆ１が、それぞれ、ＥＯボード１４の電極孔１７の該押圧方向の側壁，及び第２の光ファイバＯｆ２の側面に接触する。これにより、ＥＯチップ１１がＥＯボード１４に装着され、電極ピン１６と電極孔１７とが電気的に接続され、第１の光ファイバＯｆ１と第２の光ファイバＯｆ２とが光学的に接続される。
【０１５７】
次に、ＥＯチップ１１をＥＯボード１４から取り外すには、上記の状態から、操作部２１を引いてレバー２０を垂直状態に起こし、ＥＯチップ１１をボード１４から引き抜く。これにより、ＥＯチップ１１がＥＯボード１４から取り外される。
【０１５８】
なお、上記の説明では、ＥＯチップ１１がＥＯボード１４に装着されたとき、第１の光ファイバＯｆ１と第２の光ファイバＯｆ２とが接触するようにしているが、第１の光ファイバＯｆ１と第２の光ファイバＯｆ２とが所定の間隔を有するようにしてもよい。
【０１５９】
また、上記の説明では、第１の光ファイバＯｆ１を、ＥＯチップ１１の下面に突設しているが、ＥＯチップ１１に、外部から接触可能なように突設すればよい。
【０１６０】
また、上記の説明では、第２の光ファイバＯｆ２を、ＥＯボード１４に凹設した光ファイバ挿入孔１５の内壁面に突設しているが、第１の光ファイバＯｆ１と所定の位置関係となるようにＥＯボード１４に突設すればよい。
【０１６１】
以上のように、本実施の形態１８においては、ＥＯチップ１１がＥＯボード１４の所定の位置に装着されたとき、ＥＯチップ１１のチップ側光接続手段としての第１の光ファイバＯｆ１と、ＥＯボード１４のボード側光接続手段としての第２の光ファイバＯｆ２とが、実施の形態１による光導波路を形成するため、結合効率が１となり、ＥＯチップ１１とＥＯボード１４とが高効率で光学的に接続される。また、第１の光ファイバＯｆ１と第２の第１の光ファイバＯｆ２とは、互いの先端部が接触し、あるいは所定の間隔となることにより、光学的に接続されるため、ＥＯチップ１１とＥＯボード１４とを容易に光学的に接続することができ、該接続部の構成が簡単なものとなる。
【０１６２】
なお、上記実施の形態２〜１８では、第１，第２の光ファイバＯｆ１，Ｏｆ２と第１の光ファイバ／第２の光ファイバ直交軸Ａｘ３との交差角、第１の光ファイバＯｆ１と第２の光ファイバＯｆ２との交差角、第３，第４の光ファイバＯｆ３，Ｏｆ４と第３の光ファイバ／第４の光ファイバ直交軸Ａｘ９との交差角、第１の光ファイバＯｆ１と第２の光ファイバＯｆ２との交差角、各光ファイバＯｆ１，Ｏｆ２の傾斜端面Ｆ１，Ｆ２の傾斜角、及び光ファイバ間隔ｄが理想値であるものとしているが、これら各角度，及び光ファイバ間隔ｄを、理想値に近い範囲内で、必要とされる結合効率に応じた値に設定することができる。
【０１６３】
また、上記実施の形態１０〜１３，１５〜１７では、第１の光ファイバの傾斜端面Ｆ１と第３の光ファイバの傾斜端面Ｆ３とが平行であるとしているが、略平行であれば構わない。
【０１６４】
また、上記実施の形態２〜１８では、光導波部材として、コア１とクラッド２とからなる光ファイバを用いているが、その半径方向に徐々に小さくなるように屈折率を変化せしめてなるロッドレンズを用いてもよい。
【０１６５】
また、上記実施の形態２〜１８では、光導波部材は、中心軸方向に一定な径を有するものとしているが、中心軸方向に変化する径を有するものであってもよい。
【０１６６】
また、上記実施の形態１８では、ＥＯチップ１１をＥＯボード１４に装着すると、ＥＯチップ１１の第１の光ファイバＯｆ１とＥＯボード１４の第２の光ファイバＯｆ２とが実施の形態１の光導波路を形成するようにしているが、これに限らず、ＥＯチップ１１をＥＯボード１４に装着すると、ＥＯチップ１１の光導波部材とＥＯボード１４の光導波部材，又は光導波部材及びロッドレンズ部材とが、実施の形態２〜５の導波路、又は実施の形態１０〜１３の導波路を形成するようにしてもよい。
【０１６７】
また、上記実施の形態１５〜１８では、本発明の光導波路を、光合分波器、光パラレルバス、及び光電子集積装置に応用する場合を示しているが、本発明の光導波路は、これに限らず、光導波部材間の接続を必要とする用途に広く応用することができ、例えば、ＥＯボードのバックプレーンに光導波部材を配線するとともにＥＯボードに光導波部材を突設し、ＥＯボードをバックプレーンに差し込むと、ＥＯボードに突設された光導波部材とバックプレーンに配線された光導波部材とが、上記実施の形態２〜５の導波路、又は実施の形態１０〜１３の導波路を形成するようにすることができる。
【０１６８】
【発明の効果】
以上のように、請求項１の発明に係る光導波路によれば、一方の光導波部材に光ビームを入射せしめると、該入射せしめた光ビームは、該一方の光導波部材の傾斜端面の中心部で全反射され、第１の光導波部材／第２の光導波部材直交軸に沿って進行し、他方の光導波部材の傾斜端面の中心部で全反射されて該他方の光導波部材の中心軸に沿って伝搬するが、この際に、一方の光導波部材の傾斜端面の中心で反射されて径が拡がった光ビームが、互いに略９０°ねじれた位置関係にある両光導波部材の側面により、光ビームの横断面方向において略均等な収束効果を受け、他方の光導波部材の傾斜端面の中心にて、該他方の光導波部材を光ビームが伝搬する際の径と略同じ径を有するものとなるため、該他方の光導波部材の傾斜端面で反射された光ビームの略全部が該他方の光導波部材の光ビームを伝搬する部分に入射することとなり、両光導波部材間の結合効率が略１となる。このため、光配線を高結合効率でもって直角方向に引き回すことが可能となる。
【０１６９】
また、請求項２の発明に係る光導波路によれば、第１の光導波部材の傾斜端面と第３の光導波部材の傾斜端面との間隔に応じて、該第１の光導波部材の傾斜端面における反射率が変化するため、該間隔を適宜設定することにより、第１の光導波部材から光ビームを入射せしめた場合には、該入射せしめた光ビームが、該第１の光導波部材の傾斜端面で所定の比率で分波されて第２，第３の光導波部材に入射し、第２，第３の光導波部材から光ビームをそれぞれ入射せしめた場合には、該入射せしめた２つの光ビームが第１の光導波部材の傾斜端面で所定の比率で合波されて第１の光導波部材に入射する。このため、光ビームを合分波することができ、かつ光配線を高結合効率でＴ字状に引き回すことができる光導波路を提供することができる。
【０１７０】
また、請求項３の発明に係る光導波路によれば、第１の光導波部材と第３の光導波部材との間隔は微小なものであることから、第１の光導波部材／第２の光導波部材直交軸と第３の光導波部材／第４の光導波部材直交軸とは略一致するため、第１の光導波部材に入射せしめた光ビームは、第２の光導波部材と第３の光導波部材とに分配され、第２の光導波部材に入射せしめた光ビームは、第１の光導波部材と第４の光導波部材とに分配され、第３の光導波部材に入射せしめた光ビームは、第４の光導波部材と第１の光導波部材とに分配され、第４の光導波部材に入射せしめた光ビームは、第３の光導波部材と第２の光導波部材とに分配される。このため、４つの光導波部材のいずれを入力ポートとして用いても、光ビームを分波することができる光導波路を提供することができる。
【０１７１】
また、請求項４の発明に係る光導波路によれば、一方の光導波部材に光ビームを入射せしめると、該入射せしめた光ビームは、該一方の光導波部材の傾斜端面の中心部で全反射され、第１の光導波部材／第２の光導波部材直交軸に沿って進行し、他方の光導波部材の傾斜端面の中心部で全反射されて該他方の光導波部材の中心軸に沿って伝搬するが、この際に、一方の光導波部材の傾斜端面の中心で反射されて径が拡がった光ビームが、互いに略９０°ねじれた位置関係にある一方の光導波部材及びロッドレンズ部材の側面並びにロッドレンズ部材及び他方の光導波部材の側面により、光ビームの横断面方向において略均等な収束効果を受け、他方の光導波部材の傾斜端面の中心にて、該他方の光導波部材を光ビームが伝搬する際の径と略同じ径を有するものとなるため、該他方の光導波部材の傾斜端面で反射された光ビームの略全部が該他方の光導波部材の光ビームを伝搬する部分に入射することとなり、両光導波部材間の結合効率が略１となる。このため、光配線を高結合効率でもって、同一平面内でＵ字状に引き回すことが可能となる。
【０１７２】
また、請求項５の発明に係る光導波路によれば、第１の光導波部材の傾斜端面と第３の光導波部材の傾斜端面との間隔に応じて、該第１の光導波部材の傾斜端面における反射率が変化するため、該間隔を適宜設定することにより、第１の光導波部材から光ビームを入射せしめた場合には、該入射せしめた光ビームが、該第１の光導波部材の傾斜端面で所定の比率で分波されて第２，第３の光導波部材に入射し、第２，第３の光導波部材から光ビームをそれぞれ入射せしめた場合には、該入射せしめた２つの光ビームが第１の光導波部材の傾斜端面で所定の比率で合波されて第１の光導波部材に入射する。このため、光ビームを合分波することができ、かつ光配線を高結合効率でもって同一平面内でｈ字状に引き回すことができる光導波路を提供することができる。
【０１７３】
また、請求項６の発明に係る光導波路によれば、一方の光導波部材に光ビームを入射せしめると、該入射せしめた光ビームは、該一方の光導波部材の傾斜端面の中心部で全反射され、第１の光導波部材／第２の光導波部材直交軸に沿って進行し、他方の光導波部材の傾斜端面の中心部で全反射されて該他方の光導波部材の中心軸に沿って伝搬するが、この際に、一方の光導波部材の傾斜端面の中心で反射されて径が拡がった光ビームが、互いに略９０°ねじれた位置関係にある一方の光導波部材及びロッドレンズ部材の側面並びにロッドレンズ部材及び他方の光導波部材の側面により、光ビームの横断面方向において略均等な収束効果を受け、他方の光導波部材の傾斜端面の中心にて、該他方の光導波部材を光ビームが伝搬する際の径と略同じ径を有するものとなるため、該他方の光導波部材の傾斜端面で反射された光ビームの略全部が該他方の光導波部材の光ビームを伝搬する部分に入射することとなり、両光導波部材間の結合効率が略１となる。このため、光配線を高結合効率でもってＳ字状に引き回すことが可能となる。
【０１７４】
また、請求項７の発明に係る光導波路によれば、第１の光導波部材の傾斜端面と第３の光導波部材の傾斜端面との間隔に応じて、該第１の光導波部材の傾斜端面における反射率が変化するため、該間隔を適宜設定することにより、第１の光導波部材から光ビームを入射せしめた場合には、該入射せしめた光ビームが、該第１の光導波部材の傾斜端面で所定の比率で分波されて第２，第３の光導波部材に入射し、第２，第３の光導波部材から光ビームをそれぞれ入射せしめた場合には、該入射せしめた２つの光ビームが第１の光導波部材の傾斜端面で所定の比率で合波されて第１の光導波部材に入射する。このため、光ビームを合分波することができ、かつ光配線を高結合効率でもって同一平面内でｈ字状に引き回すことができる光導波路を提供することができる。
【０１７５】
また、請求項８の発明に係る光導波路によれば、請求項１，４，６のいずれかの光導波路において、第１の光導波部材，及び第２の光導波部材を、各々の光が伝搬する部分の屈折率を、各々の傾斜端面の周囲の媒質の屈折率と異ならしめることにより、該傾斜端面の中心部で該傾斜端面の中心軸に対し略４５度の角度で入射する光を全反射することが可能なものとしたので、傾斜端面のみで光ビームを全反射することができるため、傾斜端面の構成が簡単なものとなる。
【０１７６】
また、請求項９の発明に係る光導波路によれば、請求項１，４，６のいずれかの光導波路において、第１の光導波部材，及び第２の光導波部材を、各々の傾斜端面に金属層を配設することにより、該傾斜端面の中心部で該傾斜端面の中心軸に対し略４５度の角度で入射する光を全反射することが可能なものとしたので、傾斜端面に入射する光が金属層で反射されるため、光導波部材の屈折率が傾斜端面での全反射条件を満たさないときでも、該全反射条件を満たすようにすることができるとともに、グースヘンシェンシフトを考慮する必要がなくなる。
【０１７７】
また、請求項１０の発明に係る光導波路によれば、請求項１，４，６のいずれかの光導波路において、第１の光導波部材，第２の光導波部材を、各々の傾斜端面に、相隣合う層の屈折率を互いに異ならしめてなる多層の誘電体層を配設することにより、該傾斜端面の中心部で該傾斜端面の中心軸に対し略４５度の角度で入射する光を全反射することが可能なものとしたので、傾斜端面に入射する光が多層の誘電体層で反射されるため、光導波部材の屈折率が傾斜端面での全反射条件を満たさないときでも、該全反射条件を満たすようにすることができる。
【０１７８】
また、請求項１１の発明に係る光導波路によれば、請求項１，４，６のいずれかの光導波路において、第１の光導波部材，及び第２の光導波部材の少なくともいずれかを、傾斜端面に多層の誘電体層を配設することにより該傾斜端面の中心部で該傾斜端面の中心軸に対し略４５度の角度で入射する光を全反射することが可能なものとし、かつ、該多層の誘電体層を、波長に対し選択的に入射光を全反射するものとしたので、一方の光導波部材に、特定の波長以上又は特定の波長以下の波長の光ビームを入射せしめたときのみ、該入射せしめた光ビームが他方の光導波部材に伝達されるため、波長選択フィルタとして用いることができる。
【０１７９】
また、請求項１２の発明に係る光導波路によれば、請求項１１の光導波路において、第１の光導波部材，及び第２の光導波部材が、共に、多層の誘電体層を配設されてなり、かつ該双方の多層の誘電体層が、互いに異なる波長に対し選択的に入射光を全反射するものであるようにしたので、双方の多層の誘電体層の波長選択性を適宜組み合わせて設定することにより、一方の光導波部材に、特定の帯域の波長の光ビームを入射せしめたときのみ、該入射せしめた光ビームが他の光導波部材に伝達され，又は伝達されないようにすることができるため、帯域通過フィルタ又は帯域阻止フィルタとして用いることができる。
【０１８０】
また、請求項１３の発明に係る光導波路によれば、請求項１，２，４，５，６，７，８のいずれかの光導波路において、その中心軸がその傾斜端面で第１の光導波部材／第２の光導波部材直交軸と交差する各光導波部材を、該各光導波部材の、該その傾斜端面に平行でかつ該その中心軸に沿って伝搬する光に対するグースヘンシェンシフトによる見かけ上の反射点を中心に有する仮想傾斜端面が、上記各請求項の光導波路において該各光導波部材の傾斜端面が存在する位置に位置するように、ずらせて配置したので、グースヘンシェンシフトによる反射点のズレが補正され、その分、第１，第２の光導波部材間の結合効率を高めることができる。
【０１８１】
また、請求項１４の発明に係る光導波路によれば、請求項３の光導波路において、その中心軸がその傾斜端面で第１の光導波部材／第２の光導波部材直交軸と交差する各光導波部材，及びその中心軸がその傾斜端面で第３の光導波部材／第４の光導波部材直交軸と交差する各光導波部材を、該各光導波部材の、該その傾斜端面に平行でかつ該その中心軸に沿って伝搬する光に対するグースヘンシェンシフトによる見かけ上の反射点を中心に有する仮想傾斜端面が、請求項３の光導波路において該各光導波部材の傾斜端面が存在する位置に位置するように、ずらせて配置したので、グースヘンシェンシフトによる反射点のズレが補正され、その分、第１，第２の光導波部材間、及び第３，第４の光導波部材間の結合効率を高めることができる。
【０１８２】
また、請求項１５の発明に係る光導波路によれば、請求項１〜１４のいずれかの光導波路において、各光導波部材をコアとクラッドとからなるものとし、互いの側面により光ビームに対する収束効果を生ぜしめる部材間の間隔を所定の式により定めたものとしたので、該間隔を容易に設定することができる。
【０１８３】
また、請求項１５の発明に係る光合分波器によれば、請求項２に記載の光導波路の第１の光導波部材の傾斜端面と第３の光導波部材の傾斜端面との間隔を変化せしめることができるようにしたので、該間隔を変化させると、これに応じて第１の光導波部材の傾斜端面における光の合分波の比率が変化する。このため、高い効率で合分波することができ、かつ該合分波の比率を変化させることができる光合分波器を提供することができる。
【０１８４】
また、請求項１６の発明に係る光合分波器によれば、請求項２に記載の光導波路の、第１の光導波部材の傾斜端面と第３の光導波部材の傾斜端面との間に、その端面に入射する光を波長に対し選択的に全反射する波長選択フィルタを介挿したので、第１の光導波部材に、波長選択フィルタの中心波長より小さい波長を有する光と該中心波長より大きい波長を有する光とからなる光ビームを入射せしめると、該入射せしめた光ビームのうち、いずれか一方の波長を有する光は、波長選択フィルタにより反射され，又は通過せしめられて第２の光導波部材，又は第３の光導波部材に出力され、他方の波長を有する光は、波長選択フィルタにより通過せしめられ，又は反射されて第３の光導波部材，又は第２の光導波部材に出力され、これにより、入射せしめた光ビームが波長分割される。このため、波長分割可能な光合分波器を提供することができる。
【０１８５】
また、請求項１７に係る光パラレルバスによれば、光を透過可能な材料からなり、ある径の円柱形状を有し、その中心軸に沿って光ビームが伝搬可能なように半径方向にその屈折率を異ならしめてなり、その一端に中心軸に対し略４５度傾斜した傾斜端面を有し、上記光ビームが伝搬する部分の屈折率と該傾斜端面の周囲の媒質の屈折率との相違により、該傾斜端面の中心部にて該傾斜端面の中心軸に対し略４５度の角度で入射する光を全反射することが可能なｎ（ｎ：２以上の自然数）本の第１の光導波部材、及び該第１の光導波部材と同じ構造を有し、その一端にその中心軸に対し略４５度傾斜した傾斜端面を有するｎ本の第３の光導波部材を有し、上記ｎ本の第１の光導波部材を、該各第１の光導波部材の中心軸が互いに平行で全て同じ平面内に位置し、該各第１の光導波部材の中心軸及び傾斜端面の中心軸を含む平面が全て上記平面に垂直となり、かつ該各第１の光導波部材の傾斜端面が全て同じ方向を向きかつ該第１の光導波部材の配列方向から見て互いに重ならないように配置し、上記ｎ本の第３の光導波部材を、上記ｎ本の第１の光導波部材に１対１で対応するようにして、該第３の光導波部材の中心軸が、対応する第１の光導波部材の中心軸に一致し、かつ該第３の光導波部材の傾斜端面が、対応する第１の光導波部材の傾斜端面に対し、所定の間隔で略平行となるよう配置してなる第１の光パラレルバスと、光を透過可能な材料からなり、ある径の円柱形状を有し、その中心軸に沿って光ビームが伝搬可能なように半径方向にその屈折率を異ならしめてなり、その一端に中心軸に対し略４５度傾斜した傾斜端面を有し、該傾斜端面の中心部にて該傾斜端面の中心軸に対し略４５度の角度で入射する光を全反射することが可能なｎ本の第２の光導波部材を有し、該ｎ本の第２の光導波部材を、上記ｎ本の第１の光導波部材に１対１で対応するようにして、該各第２の光導波部材の傾斜端面の中心が、該各第１の光導波部材の傾斜端面の中心にて該傾斜端面の中心軸を挟むようにして該各第１の光導波部材の中心軸に略直交する各第１の光導波部材／第２の光導波部材直交軸上に位置し、該各第２の光導波部材の中心軸が、互いに平行で全て同じ平面内に位置し、かつ該各第２の光導波部材の傾斜端面の中心軸を挟むようにして上記各第１の光導波部材／第２の光導波部材直交軸に略直交するとともに該各第１の光導波部材／第２の光導波部材直交軸方向から見て該各第１の光導波部材の中心軸に対し略９０度の交差角を有し、該各第１の光導波部材の傾斜端面と該各第２の光導波部材の傾斜端面とが、上記各第１の光導波部材／第２の光導波部材直交軸方向から見て互いに反対の方向を向き、かつ該各第２の光導波部材と該各第１の光導波部材との間隔が、一方の光導波部材に光ビームを入射せしめたとき、該一方の光導波部材の傾斜端面の中心で反射され、かつ該反射により径が拡がった光ビームが、両光導波部材の側面による収束効果を受けて、他方の光導波部材を光ビームが伝搬する際の径と略同じ径を有するものとなる位置に、該他方の光導波部材の傾斜端面の中心が位置するような間隔となるように配置してなる第２の光パラレルバスとを備えたものであり、第１の光導波部材及び第３の光導波部材を複数平行に平面状に配列してなる第１の光パラレルバスと、第１の光導波部材と１対１で対応する第２の光導波部材を平行に平面状に配列してなる第２の光パラレルバスとは、その配列方向から見てその傾斜端面が重ならないように配置された各第１の光導波部材に対し、各第２の導波部材が、第１，第２の光導波部材の配列面に垂直な方向から見て、双方の傾斜端面が重なるようにして互いに略直角に交差し、各第３の光導波部材が所定の間隔を有して第１の光導波部材の延長上に位置するように接続されているので、各光パラレルバスを構成する導波部材を密接して配置することができるため、配線スペースを節約することができる。また、各第１の光導波部材と各第２の光導波部材とは、請求項１の光導波路を形成しているため、結合効率が略１となり、高効率なものとなる。
【０１８６】
また、請求項１９の発明に係る光電子集積装置によれば、ＥＯチップがＥＯボードの所定の位置に装着されたとき、ＥＯチップのチップ側光接続手段としての第１の光導波部材と、ＥＯボードのボード側光接続手段としての第２の光導波部材とが、請求項１の光導波路を形成するため、結合効率が略１となり、ＥＯチップとＥＯボードとが高効率で光学的に接続される。また、第１の光導波部材と第２の光導波部材とは、互いの先端部が接触し、あるいは所定の間隔となることにより、光学的に接続されるため、ＥＯチップとＥＯボードとを容易に光学的に接続することができ、該接続部の構成が簡単なものとなる。
【図面の簡単な説明】
【図１】 本発明の実施の形態１による光導波路の構成を示す図であって、斜視図（図１(a) ），図１(a) のＡ矢示図（図１(b) ），及び図１(a) のＢ矢示図（図１(c) ）である。
【図２】 本実施の形態１による光導波路の解析モデルを示す模式図である。
【図３】 本実施の形態１による光導波路のパラメータαに対する結合効率ηを示すグラフ図である。
【図４】 本実施の形態１による光導波路のクラッドの屈折率ｎ_c に対するパラメータαを示すグラフ図である。
【図５】 本実施の形態１による光導波路のクラッド半径に対する比で表した光ファイバ間隔Ｄに対するパラメータαを示すグラフ図である。
【図６】 本発明の実施の形態２による光導波路の構成を示す図であって、斜視図（図６(a) ），図６(a) のＡ矢示図（図６(b) ），及び図６(a) のＢ矢示図（図６(c) ）である。
【図７】 本発明の実施の形態３による光導波路の構成を示す図であって、斜視図（図７(a) ），図７(a) のＡ矢示図（図７(b) ），及び図７(a) のＢ矢示図（図７(c) ）である。
【図８】 本発明の実施の形態４による光導波路の構成を示す図であって、斜視図（図８(a) ），図８(a) のＡ矢示図（図８(b) ），及び図８(a) のＢ矢示図（図８(c) ）である。
【図９】 本発明の実施の形態５による光導波路の構成を示す図であって、斜視図（図９(a) ），図９(a) のＡ矢示図（図９(b) ），及び図９(a) のＢ矢示図（図９(c) ）である。
【図１０】 本発明の実施の形態６による光導波路における光ファイバの傾斜端面の構造を示す側面図である。
【図１１】 本発明の実施の形態７による光導波路における光ファイバの傾斜端面の構造を示す側面図である。
【図１２】 本発明の実施の形態９による光導波路の構成を示す斜視図である。
【図１３】 本発明の実施の形態１０による光導波路の構成を示す図であって、斜視図（図１３(a) ），図１３(a) のＡ矢示図（図１３(b) ），及び図１３(a) のＢ矢示図（図１３(c) ）である。
【図１４】 本発明の実施の形態１１による光導波路の構成を示す図であって、斜視図（図１４(a) ），図１４(a) のＡ矢示図（図１４(b) ），及び図１４(a) のＢ矢示図（図１４(c) ）である。
【図１５】 本発明の実施の形態１２による光導波路の構成を示す図であって、斜視図（図１５(a) ），図１５(a) のＡ矢示図（図１５(b) ），及び図１５(a) のＢ矢示図（図１５(c) ）である。
【図１６】 本発明の実施の形態１３による光導波路の構成を示す図であって、斜視図（図１６(a) ），図１６(a) のＡ矢示図（図１６(b) ），及び図１６(a) のＢ矢示図（図１６(c) ）である。
【図１７】 本発明の実施の形態１４による光導波路における光ファイバの傾斜端面の位置を示す図である。
【図１８】 本発明の実施の形態１５による光合分波器の構成を示す図であって、正面図（図１８(a) ），及び図１８(a) のＣ矢示図（図１８(b) ）である。
【図１９】 本発明の実施の形態１６による光合分波器の構成を示す正面図である。
【図２０】 本発明の実施の形態１７による光パラレルバスの構成を示す図であって、上面図（図２０(a) ），及び図２０(a) のＥ矢示図（図２０(b) ）である。
【図２１】 本発明の実施の形態１８による光電子集積装置の構成を示す斜視図である。
【図２２】 従来の光ファイバの接続方法を示す側面図である。
【符号の説明】
１ コア、２ クラッド、３ 金属ミラー、４ 多層膜ミラー、４ａ 第１の多層膜ミラー、４ｂ 第２の多層膜ミラー、５ 波長選択フィルタ、６ 光ファイバ固定溝、７ 基板、１０ 光電子集積装置、１１ ＥＯチップ、１２ Ｅボード層、１３ Ｏボード層、１４ ＥＯボード、１５ 光ファイバ挿入孔、１６電極ピン、１７ 電極孔、１８ 位置決め用凸部、１９ 位置決め用凹部、２０ レバー、２１ 操作部、２２ 押圧部、２３ 回転軸、２４ 支持部材、２５〜２７ 光ファイバ、１００ ロッドレンズ、１０１ 半板部、１０２ 半円部、Ａｘ１ 第１の光ファイバの中心軸、Ａｘ２ 第２の光ファイバの中心軸、Ａｘ３ 第１の光ファイバ／第２の光ファイバ直交軸、Ａｘ４ 第１の光ファイバの傾斜端面の中心軸、Ａｘ５ 第２の光ファイバの傾斜端面の中心軸、Ａｘ６ロッドレンズの中心軸、Ａｘ７ 第３の光ファイバの中心軸、Ａｘ８ 第４の光ファイバの中心軸、Ａｘ９ 第３の光ファイバ／第４の光ファイバ直交軸、Ａｘ１０ 第３の光ファイバの傾斜端面の中心軸、Ａｘ１１ 第４の光ファイバの傾斜端面の中心軸、Ｂｕ 光パラレルバス、Ｂｕ１ 第１の光パラレルバス、Ｂｕ２ 第２の光パラレルバス、Ｃｐ１ 第１の光ファイバの傾斜端面の中心点、Ｃｐ２ 第２の光ファイバの傾斜端面の中心点、Ｃｐ３ 第３の光ファイバの傾斜端面の中心点、Ｃｐ４ 第４の光ファイバの傾斜端面の中心点、Ｆ１ 第１の光ファイバの傾斜端面、Ｆ２ 第２の光ファイバの傾斜端面、Ｆ３ 第３の光ファイバの傾斜端面、Ｆ４ 第４の光ファイバの傾斜端面、ｄ 光ファイバ間隔、ｎ_c クラッドの屈折率、ｎ_e 等価屈折率、Ｏｆ１ 第１の光ファイバ、Ｏｆ２ 第２の光ファイバ、Ｏｆ３ 第３の光ファイバ、Ｏｆ４ 第４の光ファイバ、Ｐ１〜Ｐ４ ポート、Ｓ 傾斜端面Ｆ１及び傾斜端面Ｆ３の間隔。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an optical waveguide, an optical multiplexer / demultiplexer, an optical parallel bus, and an optoelectronic integrated device, and more particularly, to an apparatus in which the coupling efficiency between optical waveguide members constituting the optical wiring circuit is increased.
[0002]
[Prior art]
In recent years, in the field of optical computers and optical interconnections, an optical fiber connection method as in the case of coupling an EO chip (chip in which optical elements and electronic elements are integrated) and an EO board (board having optical wiring in the board). Is a problem.
[0003]
FIG. 22 is a schematic diagram showing an example of a conventional optical fiber connection method. In the figure, reference numerals 25 to 27 denote first to third optical fibers each having a circular cross section composed of a core 1 and a clad 2, and end faces F1 to F3 inclined at 45 ° with respect to the central axis at one ends, respectively. Have. The first optical fiber 25 and the second optical fiber 26 are arranged so that their center axes coincide with each other, their inclined end faces are parallel and have a minute interval, and the third optical fiber 27 Behind the inclined end face F1 of the first optical fiber 25, the inclined end face F3 of the third optical fiber 27 is parallel to the side surface of the first optical fiber 25 in the axial direction of the first optical fiber 25, and It arrange | positions so that it may have a micro space | interval with respect to the 1st optical fiber 25. FIG.
[0004]
In such a conventional optical fiber connection method, when a light beam is incident on the first optical fiber 25, a part of the incident light beam is part of the inclined end face F1 of the first optical fiber and the second optical fiber. The light passes through the inclined end face F2 of the optical fiber and enters the second optical fiber 26, and the others are reflected by the inclined end face F1 of the first optical fiber and enter the third optical fiber 27. 26 and the third optical fiber 27, the two light beams thus incident are combined at the inclined end face F1 of the first optical fiber and incident on the first optical fiber 25. To do.
[0005]
[Problems to be solved by the invention]
However, in the above conventional connection method of the optical fiber 27, the side surface of the first optical fiber 25 is curved in the circumferential direction with respect to the inclined end surface F3 of the flat third optical fiber. There is a problem in that the coupling loss between the two optical fibers is large because the way in which the light beam passes differs in the cross-sectional direction of the light beam.
[0006]
The present invention has been made to solve such problems, and provides an optical waveguide, an optical multiplexer / demultiplexer, an optical parallel bus, and an optoelectronic integrated device having connections between optical waveguide members having high coupling efficiency. It is aimed.
[0007]
[Means for Solving the Problems]
An optical waveguide according to the present invention (Claim 1) is made of a material capable of transmitting light, has a circular cross section and a shape extending in the direction of the central axis, and a light beam can propagate along the central axis. Thus, the refractive index is varied in the radial direction of the transverse cross section, and has an inclined end face inclined at about 45 degrees with respect to the central axis at one end, and the center of the inclined end face at the center of the inclined end face A first optical waveguide member capable of totally reflecting light incident at an angle of approximately 45 degrees with respect to the axis, and a shape that is made of a material that can transmit light and that has a circular cross section and extends in the direction of the central axis And having a refractive index different in the radial direction of the cross section so that the light beam can propagate along the central axis, and having an inclined end surface inclined at about 45 degrees with respect to the central axis at one end. An angle of approximately 45 degrees with respect to the central axis of the inclined end surface at the center of the inclined end surface. And a second optical waveguide member capable of totally reflecting light incident thereon, wherein the first optical waveguide member and the second optical waveguide member are inclined with respect to the second optical waveguide member. The first optical waveguide member / the first optical waveguide member / center which is substantially orthogonal to the central axis of the first optical waveguide member with the center of the end surface sandwiching the central axis of the inclined end surface at the center of the inclined end surface of the first optical waveguide member The first optical waveguide member / second optical waveguide member is positioned on the axis orthogonal to the second optical waveguide member, and the central axis of the second optical waveguide member sandwiches the central axis of the inclined end surface of the second optical waveguide member. Substantially perpendicular to the optical waveguide member orthogonal axis of the first optical waveguide member and a crossing angle of approximately 90 degrees with respect to the central axis of the first optical waveguide member when viewed from the direction of the first optical waveguide member / second optical waveguide member orthogonal axis. And the inclined end face of the first optical waveguide member and the inclined end face of the second optical waveguide member are the first optical waveguide member / second optical waveguide. When facing the directions orthogonal to each other in the direction perpendicular to the member, and the distance between the first optical waveguide member and the second optical waveguide member is such that a light beam is incident on one of the optical waveguide members, The light beam reflected at the center of the inclined end surface of the one optical waveguide member and expanded in diameter by the reflection is subjected to the convergence effect by the side surfaces of both optical waveguide members, and the light beam propagates through the other optical waveguide member. It is arranged so that the center of the inclined end face of the other optical waveguide member is positioned at a position having a diameter substantially the same as the diameter at the time when the other optical waveguide member is positioned.
[0008]
  In the optical waveguide according to the present invention (Claim 2), in the optical waveguide (Claim 1), the first optical waveguide member has a refractive index of a portion where light propagates, and a refractive index of a medium around the inclined end surface. By making it different from the above, it is possible to totally reflect the light incident at an angle of about 45 degrees with respect to the central axis of the inclined end surface at the central portion of the inclined end surface, and to transmit the light. Made of a material having a circular cross section and a shape extending in the direction of the central axis, the refractive index being varied in the radial direction of the cross section so that the light beam can propagate along the central axis, A third optical waveguide member having an inclined end surface inclined at approximately 45 degrees with respect to the central axis at one end thereof, and the structure of the inclined end surface being the same as the structure of the inclined end surface of the first optical waveguide member; , With respect to the first optical waveguide member, the third optical waveguide member is connected to the third optical waveguide member. The central axis of the waveguide member coincides with the central axis of the first optical waveguide member, and the inclined end surface of the third optical waveguide member is at a predetermined distance from the inclined end surface of the first optical waveguide member. Arranged so as to be approximately paralleldidIs.
[0009]
An optical waveguide according to the present invention (Claim 3) is made of a material capable of transmitting light in the optical waveguide (Claim 2), and has a circular cross section and a shape extending in the central axis direction. The refractive index is varied in the radial direction of the cross section so that the light beam can propagate along the central axis, and an inclined end surface inclined at about 45 degrees with respect to the central axis is formed at one end thereof. A fourth optical waveguide member capable of totally reflecting light incident at an angle of about 45 degrees with respect to the central axis of the inclined end surface at the center of the third optical waveguide member, In the fourth optical waveguide member, the third optical waveguide member is arranged such that the center of the inclined end surface of the fourth optical waveguide member sandwiches the central axis of the inclined end surface at the center of the inclined end surface of the third optical waveguide member. Positioned on the third optical waveguide member / fourth optical waveguide member orthogonal axis substantially orthogonal to the central axis of the optical waveguide member The central axis of the fourth optical waveguide member is substantially orthogonal to the third optical waveguide member / fourth optical waveguide member orthogonal axis so as to sandwich the central axis of the inclined end surface of the fourth optical waveguide member. The third optical waveguide member / the fourth optical waveguide member has an intersection angle of about 90 degrees with respect to the central axis of the third optical waveguide member when viewed from the direction perpendicular to the third optical waveguide member, The inclined end face and the inclined end face of the fourth optical waveguide member are directed in opposite directions as viewed from the third optical waveguide member / fourth optical waveguide member orthogonal axis direction, and the fourth optical waveguide When the light beam is incident on one of the optical waveguide members, the distance between the wave member and the third optical waveguide member is reflected at the center of the inclined end surface of the one optical waveguide member, and the diameter is reduced by the reflection. The expanded light beam receives the convergence effect by the side surfaces of both optical waveguide members, and the light beam propagates through the other optical waveguide member. The diameter and substantially comes to have the same diameter position when that one in which the center of the inclined end face of said other optical waveguide member is disposed such that the interval such that position.
[0010]
An optical waveguide according to the present invention (Claim 4) is made of a material capable of transmitting light, has a circular cross section and a shape extending in the central axis direction, and a light beam can propagate along the central axis. Thus, the refractive index is varied in the radial direction of the transverse cross section, and has an inclined end face inclined at about 45 degrees with respect to the central axis at one end, and the center of the inclined end face at the center of the inclined end face A first optical waveguide member capable of totally reflecting light incident at an angle of approximately 45 degrees with respect to the axis, and a shape that is made of a material that can transmit light and that has a circular cross section and extends in the direction of the central axis And having a refractive index different in the radial direction of the cross section so that the light beam can propagate along the central axis, and having an inclined end surface inclined at about 45 degrees with respect to the central axis at one end. An angle of approximately 45 degrees with respect to the central axis of the inclined end surface at the center of the inclined end surface. A second optical waveguide member capable of totally reflecting light incident thereon and a rod lens member made of a material capable of transmitting light and having a circular cross section and a shape extending in the central axis direction. The center of the inclined end surface of the first optical waveguide member is the center of the inclined end surface of the first optical waveguide member, the first optical waveguide member, the second optical waveguide member, and the rod lens member. The second optical waveguide is positioned on the first optical waveguide member / second optical waveguide member orthogonal axis substantially orthogonal to the central axis of the first optical waveguide member so as to sandwich the central axis of the inclined end surface at The central axis of the wave member is substantially perpendicular to the first optical waveguide member / second optical waveguide member orthogonal axis so as to sandwich the central axis of the inclined end face of the second optical waveguide member, and the first optical waveguide. The member / second optical waveguide member is paired with the central axis of the first optical waveguide member as viewed from the direction perpendicular to the axis. And the first inclined end face of the first optical waveguide member and the second inclined end face of the second optical waveguide member are the first optical waveguide member / the first optical waveguide member / the second optical waveguide member. When viewed from the direction orthogonal to the direction of the two optical waveguide members, the rod lens members are oriented in a direction opposite to the first optical waveguide member between the first optical waveguide member and the second optical waveguide member. The central axis of the first optical waveguide member and the second optical waveguide member / second optical waveguide member substantially perpendicular to the orthogonal axis of the second optical waveguide member and the first optical waveguide member / second optical waveguide member as viewed from the orthogonal axis direction. The distance between the first optical waveguide member and the rod lens member, and the distance between the second optical waveguide member and the rod lens member are substantially perpendicular to the central axis of the optical waveguide member. When a light beam is incident on the optical waveguide member, it is reflected at the center of the inclined end surface of the one optical waveguide member, and the diameter is expanded by the reflection. The other optical waveguide member is in a position where the curved light beam has substantially the same diameter as the diameter capable of propagating through the other optical waveguide member due to the convergence effect by the side surfaces of both optical waveguide members and rod lens members. Are arranged so as to have an interval at which the center of the inclined end face is located.
[0011]
  In the optical waveguide according to the present invention (Claim 5), in the optical waveguide (Claim 4), the first optical waveguide member has a refractive index of a portion where light propagates as a refractive index of a medium around the inclined end surface. By making it different from the above, it is possible to totally reflect the light incident at an angle of about 45 degrees with respect to the central axis of the inclined end surface at the central portion of the inclined end surface, and to transmit the light. Made of a material having a circular cross section and a shape extending in the direction of the central axis, the refractive index being varied in the radial direction of the cross section so that the light beam can propagate along the central axis, A third optical waveguide member having an inclined end surface inclined at approximately 45 degrees with respect to the central axis at one end thereof, and the structure of the inclined end surface being the same as the structure of the inclined end surface of the first optical waveguide member; , With respect to the first optical waveguide member, the third optical waveguide member is connected to the third optical waveguide member. The central axis of the waveguide member coincides with the central axis of the first optical waveguide member, and the inclined end surface of the third optical waveguide member is at a predetermined distance from the inclined end surface of the first optical waveguide member. Arranged so as to be approximately paralleldidIs.
[0012]
An optical waveguide according to the present invention (Claim 6) is made of a material capable of transmitting light, has a circular cross section and a shape extending in the direction of the central axis, and a light beam can propagate along the central axis. Thus, the refractive index is varied in the radial direction of the transverse cross section, and has an inclined end face inclined at about 45 degrees with respect to the central axis at one end, and the center of the inclined end face at the center of the inclined end face A first optical waveguide member capable of totally reflecting light incident at an angle of approximately 45 degrees with respect to the axis, and a shape that is made of a material that can transmit light and that has a circular cross section and extends in the direction of the central axis And having a refractive index different in the radial direction of the cross section so that the light beam can propagate along the central axis, and having an inclined end surface inclined at about 45 degrees with respect to the central axis at one end. An angle of approximately 45 degrees with respect to the central axis of the inclined end surface at the center of the inclined end surface. A second optical waveguide member capable of totally reflecting light incident thereon and a rod lens member made of a material capable of transmitting light and having a circular cross section and a shape extending in the central axis direction. The center of the inclined end surface of the first optical waveguide member is the center of the inclined end surface of the first optical waveguide member, the first optical waveguide member, the second optical waveguide member, and the rod lens member. The second optical waveguide is positioned on the first optical waveguide member / second optical waveguide member orthogonal axis substantially orthogonal to the central axis of the first optical waveguide member so as to sandwich the central axis of the inclined end surface at The central axis of the wave member is substantially perpendicular to the first optical waveguide member / second optical waveguide member orthogonal axis so as to sandwich the central axis of the inclined end face of the second optical waveguide member, and the first optical waveguide. The member / second optical waveguide member is paired with the central axis of the first optical waveguide member as viewed from the direction perpendicular to the axis. The first inclined end face of the first optical waveguide member and the second inclined end face of the second optical waveguide member have the first optical waveguide member / first When viewed from the direction orthogonal to the direction of the two optical waveguide members, the rod lens members are oriented in a direction opposite to the first optical waveguide member between the first optical waveguide member and the second optical waveguide member. The central axis of the first optical waveguide member and the second optical waveguide member / second optical waveguide member substantially perpendicular to the orthogonal axis of the second optical waveguide member and the first optical waveguide member / second optical waveguide member as viewed from the orthogonal axis direction. The distance between the first optical waveguide member and the rod lens member, and the distance between the second optical waveguide member and the rod lens member are substantially perpendicular to the central axis of the optical waveguide member. When a light beam is incident on the optical waveguide member, it is reflected at the center of the inclined end surface of the one optical waveguide member, and the diameter is reflected by the reflection. In the position where the light beam spread is subjected to the convergence effect by the side surfaces of both the optical waveguide member and the rod lens member, and has the same diameter as the light beam propagating through the other optical waveguide member, The other optical waveguide member is arranged so as to have an interval at which the center of the inclined end face is located.
[0013]
  In the optical waveguide according to the present invention (invention 7), in the optical waveguide (invention 6), the first optical waveguide member has a refractive index of a portion where light propagates, and a refractive index of a medium around the inclined end surface. By making it different from the above, it is possible to totally reflect the light incident at an angle of about 45 degrees with respect to the central axis of the inclined end surface at the central portion of the inclined end surface, and to transmit the light. Made of a material having a circular cross section and a shape extending in the direction of the central axis, the refractive index being varied in the radial direction of the cross section so that the light beam can propagate along the central axis, A third optical waveguide member having an inclined end surface inclined at approximately 45 degrees with respect to the central axis at one end thereof, and the structure of the inclined end surface being the same as the structure of the inclined end surface of the first optical waveguide member; , With respect to the first optical waveguide member, the third optical waveguide member is connected to the third optical waveguide member. The central axis of the waveguide member coincides with the central axis of the first optical waveguide member, and the inclined end surface of the third optical waveguide member is at a predetermined distance from the inclined end surface of the first optical waveguide member. Arranged so as to be approximately paralleldidIs.
[0014]
An optical waveguide according to the present invention (invention 8) is the optical waveguide (any one of claims 1, 4 and 6), wherein the first optical waveguide member and the second optical waveguide member are By making the refractive index of the portion where the light propagates different from the refractive index of the medium around each inclined end face, the light enters at an angle of about 45 degrees with respect to the central axis of the inclined end face at the center of the inclined end face. The light can be totally reflected.
[0015]
An optical waveguide according to the present invention (invention 9) is the optical waveguide (any one of claims 1, 4 and 6), wherein the first optical waveguide member and the second optical waveguide member are By disposing a metal layer on the inclined end face, light incident at an angle of about 45 degrees with respect to the central axis of the inclined end face can be totally reflected at the center of the inclined end face. .
[0016]
An optical waveguide according to the present invention (invention 10) is the optical waveguide (any of claims 1, 4 and 6), wherein the first optical waveguide member and the second optical waveguide member are By providing a multi-layered dielectric layer having different refractive indexes of adjacent layers on the inclined end face, it is incident at an angle of about 45 degrees with respect to the central axis of the inclined end face at the center of the inclined end face. The light to be reflected can be totally reflected.
[0017]
An optical waveguide according to the present invention (invention 11) is the optical waveguide (any of claims 1, 4 and 6), wherein at least one of the first optical waveguide member and the second optical waveguide member. Is provided with a multilayer dielectric layer having different refractive indexes of adjacent layers on the inclined end face, so that the central part of the inclined end face is approximately 45 degrees with respect to the central axis of the inclined end face. The incident light at an angle can be totally reflected, and the multilayer dielectric layer selectively reflects the incident light selectively with respect to the wavelength.
[0018]
An optical waveguide according to the present invention (invention 12) is the optical waveguide (invention 11), wherein both the first optical waveguide member and the second optical waveguide member include the multilayer dielectric layer. The multilayer dielectric layers that are arranged are configured to selectively reflect the incident light selectively with respect to different wavelengths.
[0019]
The optical waveguide according to the present invention (Claim 13) is the optical waveguide (any one of Claims 1, 2, 4, 5, 6, 7, and 8), the central axis of which is the inclined end face, and the first waveguide Optical waveguide member / second optical waveguide member Each optical waveguide member intersecting the orthogonal axis of the optical waveguide member is connected to the inclined end face of each optical waveguide member, and Goose Henschen for light propagating along the central axis. The virtual inclined end face having the apparent reflection point due to the shift as a center is shifted so that the inclined end face of each optical waveguide member exists in the optical waveguide of each claim.
[0020]
In the optical waveguide according to the present invention (invention 14), the central axis of the optical waveguide (invention 3) intersects the first optical waveguide member / second optical waveguide member orthogonal axis at the inclined end surface. Each optical waveguide member, and each optical waveguide member whose central axis intersects the third optical waveguide member / fourth optical waveguide member orthogonal axis at its inclined end surface, and each of the inclined end surfaces of each optical waveguide member A hypothetical inclined end surface having an apparent reflection point due to Goose-Henschen shift with respect to light propagating along the central axis thereof is centered on the inclined end surface of each optical waveguide member in the optical waveguide according to claim 3 Is arranged so as to be located at a position where there is.
[0021]
In the optical waveguide according to the present invention (invention 15), in the optical waveguide (any one of claims 1 to 14), all the optical waveguide members have a certain diameter in the central axis direction, A core having a certain refractive index disposed in a region extending to a certain radius and a clad having a refractive index smaller than the refractive index of the core disposed in a region extending from the core to the outer periphery. The distance between the members that cause the convergence effect on the light beam by the side surface is d, the distance between the members is d, and the equivalent refractive index of the core is n_e, The refractive index of the cladding is n_c, Where a is the radius of the cladding, λ is the wavelength of the incident light beam, and ω is the spot size of the member that is incident the light beam, α = (n_e/ N_c) (1 + n_c+ N_cD) [(1 + n_cD + n_c-N_c ²D) (n_c-1) (1 + n_cD)]^-1/2Where α = πω²/ Λa and D = d / a.
[0022]
  An optical waveguide according to the present invention (claim 15) is the optical waveguide according to claim 2.Described inThe distance between the inclined end face of the first optical waveguide member and the inclined end face of the third optical waveguide member is set so that the central axis of the third optical waveguide member is the central axis of the first optical waveguide member. The inclined end face of the third optical waveguide member can be changed so as to maintain a state substantially parallel to the inclined end face of the first optical waveguide member. .
[0023]
  An optical waveguide according to the present invention (claim 16) is the optical waveguide according to claim 2.Described inBetween the inclined end face of the first optical waveguide member and the inclined end face of the third optical waveguide member, a wavelength selective filter that selectively totally reflects light incident on the end face with respect to the wavelength. It is inserted.
[0024]
  An optical parallel bus according to the present invention (Claim 17) is made of a material capable of transmitting light, has a cylindrical shape with a certain diameter, and radially extends so that a light beam can propagate along its central axis. Due to the difference in refractive index between the refractive index of the portion around which the light beam propagates and the refractive index of the medium around the inclined end surface N (n: a natural number of 2 or more) first optical waveguides capable of totally reflecting light incident at an angle of about 45 degrees with respect to the central axis of the inclined end surface at the center of the inclined end surface. And n third optical waveguide members having the same structure as that of the first optical waveguide member and having inclined end surfaces inclined at approximately 45 degrees with respect to the central axis at one end thereof. The first optical waveguide members of the first optical waveguide members are all the same with the central axes of the first optical waveguide members being parallel to each other. Located in a plane, each of said central axis and the inclined end faces of the first optical waveguide memberCenter axisAll the planes including the first optical waveguide member are perpendicular to the plane, and the inclined end faces of the first optical waveguide members are all oriented in the same direction and do not overlap each other when viewed from the arrangement direction of the first optical waveguide members. The n third optical waveguide members correspond to the n first optical waveguide members on a one-to-one basis, and the central axis of the third optical waveguide member corresponds to the first The inclined end face of the third optical waveguide member is arranged so as to be substantially parallel to the inclined end face of the corresponding first optical waveguide member at a predetermined interval. The first optical parallel bus is made of a material that can transmit light, has a cylindrical shape with a certain diameter, and has a refractive index different in the radial direction so that the light beam can propagate along the central axis. And has an inclined end face inclined at about 45 degrees with respect to the central axis at one end thereof. And n second optical waveguide members capable of totally reflecting light incident at an angle of approximately 45 degrees with respect to the central axis of the inclined end surface at the portion, and the n second optical waveguides The members correspond to the n first optical waveguide members on a one-to-one basis, and the center of the inclined end surface of each second optical waveguide member is the inclined end surface of each first optical waveguide member. The first optical waveguide member / second optical waveguide member orthogonal axis substantially orthogonal to the central axis of each first optical waveguide member so as to sandwich the central axis of the inclined end surface at the center of The central axes of the respective second optical waveguide members are parallel to each other and are located in the same plane, and the central axes of the inclined end surfaces of the respective second optical waveguide members are sandwiched between the first optical waveguide members / The first optical waveguide when viewed from the direction of the first optical waveguide member / second optical waveguide member orthogonal axis and substantially orthogonal to the second optical waveguide member orthogonal axis Each of the first optical waveguide members has an intersecting angle of approximately 90 degrees with respect to the central axis of the member, and the inclined end surface of each of the first optical waveguide members and the inclined end surface of each of the second optical waveguide members The second optical waveguide members are directed in opposite directions as viewed from the orthogonal axis direction, and the distance between each second optical waveguide member and each first optical waveguide member is light on one optical waveguide member. When the beam is incident, the light beam reflected at the center of the inclined end surface of the one optical waveguide member and expanded in diameter by the reflection is subjected to the convergence effect by the side surfaces of both optical waveguide members, and the other optical waveguide A second wave member is disposed at a position where the wave member has substantially the same diameter as the light beam is propagated so that the center of the inclined end surface of the other optical waveguide member is located at a distance. And an optical parallel bus.
[0025]
The optoelectronic integrated device of the present invention (Claim 19) is a chip side contact which is electrically connected to an integrated electronic element and optical element, and an optoelectronic circuit including the electronic element and the optical element, and is arranged so as to be accessible from the outside. An EO chip having a chip-side optical connection means for optically connecting an electrode for use and an optoelectronic circuit including the electronic element and the optical element to the outside, and the EO chip can be detachably mounted at a predetermined position. An electrical wiring, a board-side contact electrode that contacts the contact electrode of the EO chip when the EO chip is mounted and connected to the electrical wiring, an optical wiring comprising an optical waveguide, and the EO chip are provided. And an EO board having board-side optical connection means for connecting the chip-side optical connection means of the EO chip to the optical wiring when mounted. The chip-side optical connection means of the EO chip is connected from the outside. It is made of a material that can transmit light and protrudes from the EO chip, and has a circular cross section extending in the direction of the central axis so that the light beam can propagate along the central axis. The refractive index is varied in the radial direction of the cross section, the base end is optically connected to the electronic element of the EO chip and the optoelectronic circuit including the optical element, and the tip is approximately 45 with respect to the central axis. N (n is a natural number greater than or equal to n: 1) capable of totally reflecting light incident at an angle of about 45 degrees with respect to the central axis of the inclined end face at the center of the inclined end face. The board-side optical connecting means of the EO board is composed of a material capable of transmitting light, and has a circular cross section and a shape extending in the central axis direction. The cross section so that the light beam can propagate along the central axis; The refractive index is varied in the radial direction, the base end is connected to the optical wiring of the EO board, and the tip has an inclined end face inclined approximately 45 degrees with respect to the central axis, and the central portion of the inclined end face The n second optical waveguide members capable of totally reflecting light incident at an angle of approximately 45 degrees with respect to the central axis of the inclined end surface are the n first optical waveguides of the EO chip. When the EO chip is mounted in a one-to-one correspondence with a member, the center of the inclined end surface of each second optical waveguide member is the inclined at the center of the inclined end surface of each first optical waveguide member. Positioned on the first optical waveguide member / second optical waveguide member orthogonal axis substantially orthogonal to the central axis of each first optical waveguide member so as to sandwich the central axis of the end face, and each second optical waveguide Each of the first optical waveguide portions is arranged such that the central axis of the member sandwiches the central axis of the inclined end face of each of the second optical waveguide members. Substantially orthogonal to the axis of the first optical waveguide member as viewed from the direction of the first optical waveguide member / second optical waveguide member orthogonal axis. Each of the first optical waveguide members / second optical waveguide members has a crossing angle of 90 degrees, and the inclined end surface of each of the first optical waveguide members and the inclined end surface of each of the second optical waveguide members When the light beams are incident on one of the optical waveguide members in directions opposite to each other when viewed from the orthogonal axis direction and the distance between each of the second optical waveguide members and each of the first optical waveguide members The light beam reflected at the center of the inclined end surface of the one optical waveguide member and having a diameter expanded by the reflection is subjected to a convergence effect by the side surfaces of both optical waveguide members, and the light beam is passed through the other optical waveguide member. The center of the inclined end face of the other optical waveguide member is located at a position having substantially the same diameter as that of the propagation. UNA such that spacing is made to protrude to the EO board.
[0026]
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1 FIG.
1A and 1B are diagrams showing a configuration of an optical waveguide according to Embodiment 1 of the present invention, in which FIG. 1A is a perspective view, FIG. 1B is an A arrow view of FIG. c) is an arrow B in FIG. 1 (a). In the figure, the optical waveguide is composed of a first optical fiber Of1 and a second optical fiber Of2, and both the first and second optical fibers Of1, Of2 have a circular cross section and a central axis Ax1. , Ax2 has a linear shape with a constant diameter, one end has inclined end faces F1 and F2 made of mirror surfaces inclined by 45 ° with respect to the central axes Ax1 and Ax2, and the central portion has a predetermined diameter at the central axis And a clad 2 formed on the outside of the core 1.
[0027]
The center Cp2 of the inclined end face F2 of the second optical fiber Of2 is the center Cp1 of the inclined end face F1 of the first optical fiber Of1 of the second optical fiber Of2 with respect to the first optical fiber Of1. The second optical fiber Of2 is positioned on the first optical fiber / second optical fiber orthogonal axis Ax3 orthogonal to the central axis Ax1 of the first optical fiber Of1 so as to sandwich the central axis Ax4 of the inclined end face F1. Of the second optical fiber Of2 is perpendicular to the first optical fiber / second optical fiber orthogonal axis Ax3 so as to sandwich the central axis Ax5 of the inclined end face F2 of the second optical fiber Of2, and the first optical fiber / first optical fiber The crossing angle of 90 degrees with respect to the central axis Ax1 of the first optical fiber Of1 when viewed from the direction of the two optical fiber orthogonal axes Ax3, and the inclined end face F1 of the first optical fiber Of1 and the second optical fiber. The inclined end face F2 of the bar Of2 faces in directions opposite to each other when viewed from the first optical fiber / second fiber orthogonal axis Ax3 direction, and the second optical fiber Of2 and the first optical fiber Of1 The interval d is arranged to have a specific value described later. The first and second optical fibers Of1, Of2 are fixed by a substrate or the like (not shown).
[0028]
The first and second optical fibers Of1, Of2 are made of a material that can transmit light, that is, a dielectric or a semiconductor, for example, SiO.sub.2.₂Is used.
[0029]
The refractive index of the clad 2 is made smaller than the refractive index of the core 1, and the refractive indexes of the core 1 and the clad 2 are the refractive indexes of the medium around the optical waveguide (air in the first embodiment). On the other hand, the value is sufficiently large to satisfy the total reflection condition at the inclined end faces F1 and F2 of the first and second optical fibers Of1 and Of2.
[0030]
Further, in order to obtain the inclined end faces F1 and F2 of the first and second optical fibers Of1 and Of2, for example, first, a polishing machine having a polished surface with a rough finished surface is used, and the end of the optical fiber is polished to the polished surface. Then, the surface is polished at an angle of 45 ° to the surface, and then polished in the same manner using a polishing machine having a polished surface with a fine finished surface roughness, and finally the final polishing is performed. Thereby, the inclined end surfaces F1 and F2 which consist of mirror surfaces inclined 45 degrees with respect to the central axis can be obtained.
[0031]
Next, an analysis model of the optical waveguide configured as described above will be described.
FIG. 2 is a schematic diagram showing an analysis model. As shown in the figure, it is assumed that the first optical fiber Of1 and the second optical fiber Of2 are in contact with each other, and a light beam is incident on the first optical fiber Of1 and is emitted from the second optical fiber Of2. And Also, the coordinate axis is taken so that the traveling direction of the incident beam of the first optical fiber Of1 is the x direction and the traveling direction of the outgoing beam of the second optical fiber Of2 is the -y direction. For the sake of simplicity, the Goose Henschen shift is ignored. In the drawing, the diameter of the core 1 is greatly exaggerated for easy understanding.
[0032]
In this case, the light beam incident on the first optical fiber Of1 is totally reflected at the inclined end face F1 of the first optical fiber and the inclined end face F2 of the second optical fiber, and is bent at a right angle. A bent light beam is considered to go straight if the Goose Henschen shift is ignored. At this time, the incident beam (propagation mode) traveling in the x direction and the outgoing beam traveling in the -y direction are both considered to be propagation problems of the mode traveling in the z direction. Accordingly, the connecting portion between the first optical fiber Of1 and the second optical fiber Of2 is provided with a refractive index n of the cladding._cCan be equivalently replaced with the half-plate part 101 and the semi-circular part 102.
[0033]
Next, the coupling efficiency η (hereinafter simply referred to as coupling efficiency η) from the first optical fiber Of1 to the second optical fiber Of2 is obtained. The mode function in a single mode optical fiber can be approximated by a Gaussian function. Here, the spot size (light beam diameter) in the optical fiber is ω, and the light propagating in the optical fiber is converted into the equivalent refractive index n of the core 1_eWhen approximated by a Gaussian beam having a spot size ω propagating in a homogeneous fiber having λ, the ABCD parameter of the ray matrix at the connection between the first optical fiber Of1 and the second optical fiber Of2 is ,
[0034]
[Expression 1]

[0035]
It becomes. Here, a is the radius of the cladding (= radius of the optical fiber).
[0036]
Therefore, the spot size in the first optical fiber Of1 is_A, The spot size in the second optical fiber Of2 is ω_BThen, the ratio ω_A/ Ω_BFrom equation (1)
[0037]
[Expression 2]

[0038]
It becomes. Here, if the wavelength of the light beam is λ, the parameter α is α = πω_A ²/ Λa, which equivalently represents the spot size of the light beam.
[0039]
The coupling efficiency η is
[0040]
[Equation 3]

[0041]
It is expressed.
[0042]
Where the refractive index n of the cladding_cAs a parameter, the relationship between the coupling efficiency η and the parameter α is shown in FIG. In FIG. 3, it can be seen that the coupling efficiency η is the highest in the vicinity where the parameter α is 2, and becomes 1, and the coupling efficiency η decreases as the parameter α further increases.
[0043]
Next, when obtaining the condition that the coupling efficiency η = 1, from the equations (2) and (3),
[0044]
[Expression 4]

[0045]
It becomes.
[0046]
The parameter α in this equation (4) and the refractive index n of the cladding_cFIG. 4 shows the relationship.
[0047]
Therefore, from FIG. 3 and FIG. 4, the parameter α and the refractive index n of the clad_cIt can be seen that the coupling efficiency η can be set to 1 by appropriately selecting. Further, the condition for the coupling efficiency η to be 1 is that the equivalent refractive index n of the core 1 is obtained from the equation (4)._e, Refractive index n of clad 2_c, And the parameter α, and the parameter α is determined by the spot size ω of the optical fiber, the radius a of the cladding, and the wavelength λ of the light beam. In the above analysis, it is assumed that the medium around the optical waveguide is air. However, when the medium around the optical waveguide is a substance other than air, depending on the refractive index of the medium. The analysis result may be corrected. Therefore, the condition for the coupling efficiency η to be 1 is uniquely determined if the wavelength λ of the incident light beam and the structure of the optical fiber are determined.
[0048]
Next, a case where the first optical fiber Of1 and the second optical fiber Of2 are separated will be described. The distance between the first optical fiber Of1 and the second optical fiber Of2 (hereinafter referred to as the optical fiber distance) is d, and the ratio of the optical fiber distance d to the cladding radius a (hereinafter referred to as the ratio to the cladding radius). D / a is described as D) and the condition that the coupling efficiency η is 1 is obtained in the same manner as described above.
[0049]
[Equation 5]

[0050]
It becomes. Therefore, it can be seen that by satisfying the expression (5), the coupling efficiency η can be set to 1 even when the first optical fiber Of1 and the second optical fiber Of2 are separated.
[0051]
In addition, the following condition must be satisfied with respect to the optical fiber distance D expressed by the ratio to the cladding radius from the equation (5).
[0052]
[Formula 6]

[0053]
The relationship between the parameter α in this equation (5) and the optical fiber distance D expressed as a ratio to the cladding radius is expressed by the refractive index n of the cladding._cIs shown as a parameter in FIG. In FIG. 5, an arbitrary refractive index n_cOn the other hand, in a region where the optical fiber distance D expressed by the ratio to the cladding radius is small, there is a parameter α at which the coupling efficiency η is 1, but when the optical fiber distance D expressed by the ratio to the cladding radius is greater than a certain value. In that region, there is no parameter α at which the coupling efficiency η is 1. Therefore, it can be seen that the coupling efficiency η cannot be 1 when the first optical fiber Of1 and the second optical fiber Of2 are separated from each other by a certain distance.
[0054]
Accordingly, in the first embodiment, the optical fiber interval d is set so as to satisfy the equation (5), and this setting depends on the wavelength of the incident light beam, and the spot size in the first optical fiber Of1. ω_A, Spot size ω in the second optical fiber Of2_B, Cladding radius a, and cladding refractive index n_cIs appropriately selected so that the distance d between the optical fibers becomes a desired value. Also, the spot size ω in the first and second optical fibers_A, Ω_BCan be changed relatively easily by using a thermal diffusion technique such as the dopant of the core 1.
[0055]
Next, the polarization characteristics of the connection portion between the first optical fiber Of1 and the second optical fiber Of2 will be described.
[0056]
As shown in FIG. 2, in the optical waveguide according to the first embodiment, the light beam incident on the optical fiber is reflected by the two inclined end faces F1 and F2 which are twisted at right angles to each other. When TM-like incidence occurs at one inclined end face, TE-like incidence occurs at the other inclined end face (or vice versa). Therefore, basically, the connection portion between the first optical fiber Of1 and the second optical fiber Of2 exhibits polarization independence.
[0057]
Next, the operation of the optical waveguide configured as described above will be described with reference to FIGS. In these drawings, when a light beam having a predetermined wavelength λ is incident on the other end of the first optical fiber Of1, the incident light beam is spotted along the central axis Ax1 at the center of the first optical fiber Of1. Size ω_AAnd is reflected at a central point Cp1 of the inclined end face F1 of the first optical fiber Of1 at an angle of 45 ° with respect to the central axis Ax4 of the inclined end face F1, and the first optical fiber / second optical fiber orthogonal axis It passes along the side surface of the first optical fiber Of1 and the side surface of the second optical fiber Of2 along Ax3, and is 45 ° with respect to the central axis Ax5 of the inclined end surface F2 at the inclined end surface F2 of the second optical fiber Of2. Reflecting at an angle, the center size of the second optical fiber Of2 is spot size ω along the central axis Ax2_BAnd is emitted from the other end of the second optical fiber Of2.
[0058]
At this time, the light beam reflected at the center Cp1 of the inclined end face F1 of the first optical fiber expands in diameter because there is no light confinement structure in the radial direction of the first optical fiber Of1, and this diameter is increased. The light beam having the spread of the light beam receives a uniform convergence effect in the cross-sectional direction of the light beam by the side surfaces of the first and second optical fibers Of1 and Of2, which are in a positional relationship twisted by 90 °. Here, the optical fiber interval d obtained by the analysis based on the above analysis model is obtained by reflecting the light beam whose diameter is expanded by being reflected at the center Cp1 of the inclined end face F1 of the first optical fiber, by the convergence effect. Spot size ω when propagating in the optical fiber Of2_BSince the spacing is such that the center Cp2 of the inclined end face F2 of the second optical fiber is located at a position having the same diameter as that of the second optical fiber, the light beam subjected to the convergence effect is the same as that of the second optical fiber. The spot size ω in the second optical fiber Of2 at the center Cp2 of the inclined end face F2_BAnd the entire light beam reflected by the inclined end face F2 of the second optical fiber is incident on the core 1 of the second optical fiber Of2. Therefore, the coupling efficiency η between the two optical fibers Of1, Of2 is 1.
[0059]
Further, when a light beam having a predetermined wavelength λ is incident on the other end of the second optical fiber Of2, the incident light beam follows a path completely opposite to that described above, and has a coupling efficiency of 1 as described above. The second optical fiber Of2 propagates to the first optical fiber Of1, and is emitted from the other end of the first optical fiber Of1.
[0060]
In the above description, the crossing angle between the first and second optical fibers Of1, Of2 and the first optical fiber / second optical fiber orthogonal axis Ax3, the first optical fiber Of1 and the second optical fiber. The intersection angle with Of2, the inclination angles of the inclined end faces F1 and F2 of each optical fiber, and the optical fiber interval d are assumed to be ideal values. As can be inferred from the graph of FIG. Even if the optical fiber interval d is slightly deviated from the ideal value, the coupling efficiency between the optical fibers does not rapidly decrease. Therefore, each of these angles and the optical fiber interval d can be set to values according to the required coupling efficiency within a range close to the ideal value.
[0061]
Further, although the optical fiber interval d is obtained by a theoretical formula, this may be obtained, for example, by an experiment for detecting the optical fiber interval d at which the coupling efficiency is maximized.
[0062]
Moreover, although the 1st optical fiber Of1 and the 2nd optical fiber Of2 are taken as the thing of the same structure, the refractive index and diameter of both optical fibers may differ. In this case, the refractive index and the diameter of both optical fibers are determined in the same manner as described above so that the convergence effect received by the side surfaces of both optical fibers is equivalent to the convergence effect described above. Thus, the optical fiber interval d can be set.
[0063]
Moreover, although the optical fiber which consists of the core 1 and the clad 2 is used as an optical waveguide member, you may use the rod lens which changes a refractive index so that it may become small gradually in the radial direction.
[0064]
The optical waveguide member has a constant diameter in the central axis direction, but may have a diameter that changes in the central axis direction.
[0065]
Further, although the optical waveguide member is linear, the vicinity of the inclined end surface only needs to be linear, and the end portion that does not have the inclined end surface may be bent.
[0066]
As described above, according to the optical waveguide of the first embodiment, the light beam incident on one optical fiber is propagated to the other optical fiber with a coupling efficiency of approximately 1, and both optical fibers are , When viewed from the direction of the first optical fiber / second optical fiber orthogonal axis Ax3, the inclined end surfaces of the first optical fiber and the second optical fiber are arranged so as to intersect each other at right angles. It is possible to be drawn around.
[0067]
Further, according to the optical waveguide of the first embodiment, the optical fiber interval d that produces the convergence effect on the light beam by the side surfaces is determined by a predetermined theoretical formula. Can be set to
[0068]
Embodiment 2. FIG.
6A and 6B are diagrams showing a configuration of an optical waveguide according to the second embodiment of the present invention, in which FIG. 6A is a perspective view, FIG. 6B is an A arrow view of FIG. c) is an arrow B view of FIG. 6 (a). In the figure, the same reference numerals as those in FIG. 1 denote the same or corresponding parts, and the optical waveguide according to the second embodiment is composed of the first and second optical fibers Of1, Of2 of the first embodiment and the rod lens 100. Is done. The rod lens 100 has a linear shape with a circular cross section and a constant diameter in the direction of the central axis Ax6. For example, the rod lens 100 has the same diameter as the first and second optical fibers Of1, Of2, and is made of the same material. Composed. The refractive index of the rod lens 100 is the same as the refractive index of the clad of the first and second optical fibers Of1, Of2, for example.
[0069]
In the first optical fiber Of1, the second optical fiber Of2, and the rod lens 100, the center Cp2 of the inclined end face F2 of the second optical fiber Of2 is the center Cp1 of the inclined end face F1 of the first optical fiber Of1. The second optical fiber Of2 is positioned on the first optical fiber / second optical fiber orthogonal axis Ax3 perpendicular to the central axis Ax1 of the first optical fiber so as to sandwich the central axis Ax4 of the inclined end face F1. Is perpendicular to the first optical fiber / second optical fiber orthogonal axis Ax3 so as to sandwich the central axis Ax5 of the inclined end face F2 of the second optical fiber, and the first optical fiber / second optical axis The first optical fiber has a crossing angle of 0 degrees with respect to the central axis Ax1 of the first optical fiber as viewed from the direction of the optical fiber orthogonal axis Ax3 (overlapping the central axis Ax1 of the first optical fiber). The inclined end face F1 of the bar and the inclined end face F2 of the second optical fiber face in opposite directions when viewed from the first optical fiber / second optical fiber orthogonal axis Ax3 direction, and the central axis Ax6 of the rod lens 100 Is orthogonal to the first optical fiber / second optical fiber orthogonal axis Ax3 between the first optical fiber Of1 and the second optical fiber Of2, and the first optical fiber / second optical fiber. The distance between the first optical fiber Of1 and the rod lens 100 is perpendicular to the central axis Ax1 of the first optical fiber and the central axis Ax2 of the second optical fiber as viewed from the direction of the orthogonal axis Ax3, and the second The optical fiber Of2 and the rod lens 100 are arranged so that the distance between them is the predetermined distance at which the coupling efficiency η described in the first embodiment is 1.
[0070]
Next, the optical waveguide configured as described above has the positional relationship between the first optical fiber Of1 and the rod lens 100 and the positional relationship between the rod lens 100 and the second optical fiber Of2 in the first embodiment. The positional relationship between the first optical fiber Of1 and the second optical fiber Of2 is the same. Therefore, by setting the distance between the first optical fiber Of1 and the rod lens 100 and the distance between the rod lens 100 and the second optical fiber Of2 in the same manner as the optical fiber distance d in the first embodiment, The light beam can be propagated with a coupling efficiency of 1 between the first optical fiber Of1 and the rod lens 100 and between the rod lens 100 and the second optical fiber Of2.
[0071]
Here, if the diameter of the light beam is the same at the center point Cp1 of the inclined end face F1 of the first optical fiber and the center point Cp2 of the inclined end face F2 of the second optical fiber, from the core 1 of one optical fiber. Since all the emitted light beams are incident on the core 1 of the other optical fiber and the coupling efficiency is 1, the center point Cp1 of the inclined end surface F1 of the first optical fiber and the inclined end surface of the second optical fiber At the center of the rod lens 100 located between the center point Cp2 of F2, the diameter of the light beam emitted from the core 1 of one optical fiber and converged by the side surface of the optical fiber and the rod lens 100 is the other light. Although it seems that it may be larger than the diameter when entering the core 1 of the fiber, the convergence effect by the side surface of the optical fiber and the convergence effect by the side surface of the rod lens on the light beam In order to set the coupling efficiency to 1 because they do not act at the same time, as described above, at the center of the rod lens 100, the light is emitted from the core 1 of one optical fiber and converged by the side surface of the optical fiber and the rod lens 100. It is necessary that the diameter of the light beam is the same as the diameter when emitted. However, in the case where a value close to 1 is sufficient for the coupling efficiency, the diameter of the light beam incident on the core 1 of the other optical fiber is the same as that emitted from the core 1 of the one optical fiber. The interval between the first optical fiber Of1 and the rod lens 100 and the interval between the rod lens 100 and the second optical fiber Of2 may be set so as to be substantially equal.
[0072]
Next, the operation of the optical waveguide configured as described above will be described with reference to FIG.
When a light beam having a predetermined wavelength λ is incident on the other end of the first optical fiber Of1, the incident light beam has a spot size ω along the central axis Ax1 at the center of the first optical fiber Of1._AAnd is reflected at an angle of 45 ° with respect to the central axis Ax4 of the inclined end face F1 at the center point Cp1 of the inclined end face F1 of the first optical fiber Of1, and the first optical fiber / second optical fiber orthogonal axis It passes along the side surface of the first optical fiber Of1, the rod lens 100, and the side surface of the second optical fiber Of2 along Ax3, and reaches the central axis Ax5 of the inclined end surface F2 at the inclined end surface F2 of the second optical fiber Of2. Reflected at an angle of 45 ° with respect to the central portion of the second optical fiber Of2 along the central axis Ax2, the spot size ω_BAnd is emitted from the other end of the second optical fiber Of2.
[0073]
At this time, the light beam that passes between the center point Cp1 of the inclined end face F1 of the first optical fiber and the center point Cp2 of the inclined end face F2 of the second optical fiber passes through the side surface of the first optical fiber Of1. The convergence effect by the side surface of the rod lens 100 facing the first optical fiber Of1, and the convergence effect by the side surface of the second optical fiber Of2 and the side surface of the rod lens 100 facing the second optical fiber Of2 are received. All the light beams reflected by the inclined end face F1 of the first optical fiber are reflected by the inclined end face F2 of the second optical fiber and then enter the core 1 of the second optical fiber Of2. Therefore, the coupling efficiency between the two optical fibers Of1, Of2 is 1.
[0074]
Further, when a light beam having a predetermined wavelength λ is incident on the other end of the second optical fiber Of2, the incident light beam follows a path completely opposite to that described above, and has a coupling efficiency of 1 as described above. The second optical fiber Of2 propagates to the first optical fiber Of1, and is emitted from the other end of the first optical fiber Of1.
[0075]
As described above, according to the optical waveguide of the second embodiment, the light beam incident on one optical fiber is propagated to the other optical fiber with a coupling efficiency of 1, and both optical fibers are As viewed from the direction of the first optical fiber / second optical fiber orthogonal axis Ax3, the inclined end faces overlap each other and intersect each other at an angle of 0 degrees, so that the optical wiring is It becomes possible to draw in a U shape with the coupling efficiency.
[0076]
Embodiment 3 FIG.
7A and 7B are diagrams showing the configuration of the optical waveguide according to the third embodiment of the present invention, in which FIG. 7A is a perspective view, FIG. 7B is an A arrow view of FIG. c) is a view as indicated by an arrow B in FIG. In the figure, the same reference numerals as those in FIG. 6 denote the same or corresponding parts. In the optical waveguide according to the third embodiment, the central axis Ax2 of the second optical fiber Of2 is the first optical fiber / second optical fiber. The second embodiment is different from the second embodiment in that the crossing angle is 180 degrees with respect to the central axis Ax1 of the first optical fiber when viewed from the direction of the orthogonal axis Ax3.
[0077]
In the optical waveguide configured as described above, the first optical fiber according to the first embodiment has the positional relationship between the first optical fiber Of1 and the rod lens 100 and the positional relationship between the rod lens 100 and the second optical fiber Of2. This is the same as the positional relationship between the fiber Of1 and the second optical fiber Of2. Therefore, by setting the distance between the first optical fiber Of1 and the rod lens 100 and the distance between the rod lens 100 and the second optical fiber Of2 in the same manner as the optical fiber distance d in the first embodiment, The light beam can be propagated with a coupling efficiency of 1 between the first optical fiber Of1 and the rod lens 100 and between the rod lens 100 and the second optical fiber Of2.
[0078]
Next, in the optical waveguide configured as described above, when a light beam having a predetermined wavelength λ is incident on the other end of the first optical fiber Of1, the incident light beam is centered on the first optical fiber Of1. Spot size ω along central axis Ax1_AAnd is reflected at an angle of 45 ° with respect to the central axis Ax4 of the inclined end face F1 at the center point Cp1 of the inclined end face F1 of the first optical fiber Of1, and the first optical fiber / second optical fiber orthogonal axis It passes along the side surface of the first optical fiber Of1, the rod lens 100, and the side surface of the second optical fiber Of2 along Ax3, and reaches the central axis Ax5 of the inclined end surface F2 at the inclined end surface F2 of the second optical fiber Of2. Reflected at an angle of 45 ° with respect to the central portion of the second optical fiber Of2 along the central axis Ax2, the spot size ω_BAnd is emitted from the other end of the second optical fiber Of2.
[0079]
At this time, the light beam that passes between the center point Cp1 of the inclined end face F1 of the first optical fiber and the center point Cp2 of the inclined end face F2 of the second optical fiber passes through the side surface of the first optical fiber Of1. The convergence effect by the side surface of the rod lens 100 facing the first optical fiber Of1, and the convergence effect by the side surface of the second optical fiber Of2 and the side surface of the rod lens 100 facing the second optical fiber Of2 are received. All the light beams reflected by the inclined end face F1 of the first optical fiber Of1 are reflected by the inclined end face F2 of the second optical fiber and then enter the core 1 of the second optical fiber Of2. Therefore, the coupling efficiency between the two optical fibers Of1, Of2 is 1.
[0080]
Further, when a light beam having a predetermined wavelength λ is incident on the other end of the second optical fiber Of2, the incident light beam follows a path completely opposite to that described above, and has a coupling efficiency of 1 as described above. The second optical fiber Of2 propagates to the first optical fiber Of1, and is emitted from the other end of the first optical fiber Of1.
[0081]
As described above, according to the optical waveguide of the third embodiment, the light beam incident on one optical fiber is propagated to the other optical fiber with a coupling efficiency of 1, and both optical fibers are As viewed from the direction of the first optical fiber / second optical fiber orthogonal axis Ax3, the inclined end faces overlap each other and intersect with each other at an angle of 180 degrees, so that the optical wiring has high coupling efficiency. It can be drawn in an S shape.
[0082]
Embodiment 4 FIG.
8A and 8B are diagrams showing the configuration of the optical waveguide according to the fourth embodiment of the present invention, in which FIG. 8A is a perspective view, FIG. 8B is an A arrow view of FIG. 8A, and FIG. c) is a view as indicated by an arrow B in FIG. In the figure, the same reference numerals as those in FIG. 6 denote the same or corresponding parts. In the optical waveguide according to the fourth embodiment, the rod lens 100 has the same structure as the first and second optical fibers Of1, Of2. This is different from the second embodiment in that it is made of a fiber.
[0083]
In the optical waveguide configured as described above, when a light beam having a predetermined wavelength λ is incident on the other end of the first optical fiber Of1, the incident light beam is centered on the central portion of the first optical fiber Of1. The optical fiber travels along Ax1 and is reflected at a central point Cp1 of the inclined end surface F1 of the first optical fiber Of1 at an angle of 45 ° with respect to the central axis Ax4 of the inclined end surface F1, and the first optical fiber / second light. The inclined end surface passes through the side surface of the first optical fiber Of1, the core 1 of the rod lens 100, and the side surface of the second optical fiber Of2 along the fiber orthogonal axis Ax3, and the inclined end surface F2 of the second optical fiber Of2. The light is reflected at an angle of 45 ° with respect to the central axis Ax5 of F2, travels along the central axis Ax2 of the second optical fiber Of2, and is emitted from the other end of the second optical fiber Of2.
[0084]
At this time, the light beam passing between the center point Cp1 of the inclined end face F1 of the first optical fiber and the center point Cp2 of the inclined end face F2 of the second optical fiber is the same as in the second embodiment. The first optical fiber Of1, the rod lens 100, and the second optical fiber Of2 receive a convergence effect and propagate with a coupling efficiency of 1.
[0085]
Further, when a light beam having a predetermined wavelength λ is incident on the other end of the second optical fiber Of2, the incident light beam follows a path completely opposite to that described above, and has a coupling efficiency of 1 as described above. The second optical fiber Of2 propagates to the first optical fiber Of1, and is emitted from the other end of the first optical fiber Of1.
[0086]
Therefore, according to the optical waveguide of the fourth embodiment, an optical fiber can be routed in a U shape with high coupling efficiency using an optical fiber as the rod lens 100.
[0087]
Further, when the light beam propagating between the first optical fiber Of1 and the second optical fiber Of2 hits the core 1 of the optical fiber 100 as the rod lens, the core 1 enters an excited state. By taking out the laser beam generated by the excitation, the optical waveguide according to the fourth embodiment can be used as a laser.
[0088]
Embodiment 5 FIG.
9A and 9B are diagrams showing the configuration of an optical waveguide according to the fifth embodiment of the present invention. FIG. 9A is a perspective view, FIG. 9B is an A arrow view of FIG. 9A, and FIG. c) is an arrow B diagram of FIG. 9 (a). In the figure, the same reference numerals as those in FIG. 7 denote the same or corresponding parts. In the optical waveguide according to the fifth embodiment, the rod lens 100 has the same structure as the first and second optical fibers Of1, Of2. This is different from the third embodiment in that it is made of a fiber.
[0089]
In the optical waveguide configured as described above, when a light beam having a predetermined wavelength λ is incident on the other end of the first optical fiber Of1, the incident light beam is centered on the central portion of the first optical fiber Of1. The optical fiber travels along Ax1 and is reflected at a central point Cp1 of the inclined end surface F1 of the first optical fiber Of1 at an angle of 45 ° with respect to the central axis Ax4 of the inclined end surface F1, and the first optical fiber / second light. The inclined end surface passes through the side surface of the first optical fiber Of1, the core 1 of the rod lens 100, and the side surface of the second optical fiber Of2 along the fiber orthogonal axis Ax3, and the inclined end surface F2 of the second optical fiber Of2. The light is reflected at an angle of 45 ° with respect to the central axis Ax5 of F2, travels along the central axis Ax2 of the second optical fiber Of2, and is emitted from the other end of the second optical fiber Of2.
[0090]
At this time, the light beam passing between the center point Cp1 of the inclined end face F1 of the first optical fiber and the center point Cp2 of the inclined end face F2 of the second optical fiber is the same as in the third embodiment. The first optical fiber Of1, the rod lens 100, and the second optical fiber Of2 receive a convergence effect and propagate with a coupling efficiency of 1.
[0091]
Further, when a light beam having a predetermined wavelength λ is incident on the other end of the second optical fiber Of2, the incident light beam follows a path completely opposite to that described above, and has a coupling efficiency of 1 as described above. The second optical fiber Of2 propagates to the first optical fiber Of1, and is emitted from the other end of the first optical fiber Of1.
[0092]
Therefore, according to the optical waveguide of the fifth embodiment, using the optical fiber as the rod lens 100, the optical wiring can be routed in an S shape with high coupling efficiency.
[0093]
Further, when the light beam propagating between the first optical fiber Of1 and the second optical fiber Of2 hits the core 1 of the optical fiber 100 as the rod lens, the core 1 enters an excited state. By extracting laser light generated by excitation, the optical waveguide according to the fifth embodiment can be used as a laser.
[0094]
Embodiment 6 FIG.
FIG. 10 is a side view showing the structure of the inclined end face of the optical fiber in the optical waveguide according to the sixth embodiment of the present invention. In the figure, the same reference numerals as those in FIG. 1 denote the same or corresponding parts. The sixth embodiment is different from the first embodiment in that a metal mirror 3 is formed on the inclined end face F1 of the first optical fiber Of1 and the inclined end face F2 of the second optical fiber Of2. is there.
[0095]
The metal mirror 3 is formed by depositing, for example, a metal such as aluminum or silver on the inclined end faces F1 and F2 having a mirror surface by the method described in the first embodiment.
[0096]
In the optical waveguide configured as described above, the light beam incident on the inclined end faces F <b> 1 and F <b> 2 is reflected on the surface of the metal layer of the metal mirror 3. For this reason, even if it is not possible to satisfy the total reflection condition at the inclined end surfaces F1 and F2 due to the difference in refractive index because the refractive indexes of the optical fibers Of1 and Of2 are small, the total reflection at the inclined end surfaces F1 and F2 is not possible. The condition can be met. Further, since it is not necessary to consider the Goose Henschen shift, the positions of the optical fibers Of1, Of2 can be easily set.
[0097]
In the second to fifth embodiments, the metal mirror 3 can be formed on the inclined end face F1 of the first optical fiber Of1 and the inclined end face F2 of the second optical fiber Of2 in the same manner as described above. The same effect as described above can be obtained.
[0098]
Embodiment 7 FIG.
FIG. 11 is a side view showing the structure of the inclined end face of the optical fiber in the optical waveguide according to the seventh embodiment of the present invention. In the figure, the same reference numerals as those in FIG. The seventh embodiment is different from the first embodiment in that the multilayer mirror 4 is formed on the inclined end face F1 of the first optical fiber Of1 and the inclined end face F2 of the second optical fiber Of2. It is.
[0099]
The multilayer mirror 4 is made of, for example, TiO₂/ SiO₂5 to 10 layers each having a thickness of 1 μm are laminated.
[0100]
Further, the multilayer mirror 4 is formed by forming the inclined end faces F1 and F2 formed of mirror surfaces on the optical fibers Of1 and Of2 by the method described in the first embodiment, and then forming the TiO 2 on the inclined end faces F1 and F2.₂And SiO₂Are alternately deposited in layers.
[0101]
In the optical waveguide configured as described above, when a light beam is incident on the inclined end faces F1 and F2 at an angle of 45 ° with respect to the central axes Ax4 and Ax5 of the inclined end faces F1 and F2, the incident light beam is converted into the optical fiber Of1. , Of2 and the multilayer mirror 4, and the interface between each layer in the multilayer mirror 4, part of the light beam incident on one interface is reflected and the other is transmitted and incident on the next interface In this way, the light is sequentially reflected and finally most of the light is reflected. For this reason, even if the total reflection conditions at the inclined end faces F1 and F2 cannot be satisfied because the refractive indexes of the optical fibers Of1 and Of2 are small, the total reflection conditions at the inclined end faces F1 and F2 are satisfied. be able to.
[0102]
In the second to fifth embodiments, the multilayer mirror 4 can be formed on the inclined end face F1 of the first optical fiber Of1 and the inclined end face F2 of the second optical fiber Of2 in the same manner as described above. The same effects as described above can be obtained.
[0103]
Embodiment 8 FIG.
The optical waveguide according to the eighth embodiment of the present invention is the same as the optical waveguide according to the seventh embodiment in FIG. 11 except that the multilayer mirror 4 formed on the inclined end faces F1, F2 of the first and second optical fibers Of1, Of2. One of them is different from the first embodiment in that the incident light is selectively totally reflected with respect to the wavelength. In order to provide wavelength selectivity to the reflection characteristics of the multilayer mirror 4, the refractive index and thickness of the dielectric of each layer constituting the multilayer mirror 4 are selected so as to exhibit the desired wavelength selectivity for the reflection characteristics. That's fine.
[0104]
In the optical waveguide configured as described above, only when a light beam having a wavelength greater than or equal to a specific value is incident on one optical fiber, the incident light beam has the wavelength selectivity. Since it is reflected by the inclined end face on which the multilayer mirror 4 is formed and transmitted to another optical fiber, it can be used as a wavelength selective filter.
[0105]
In the above description, one of the multilayer mirrors 4 formed on the inclined end faces F1 and F2 of the first and second optical fibers Of1 and Of2 has a reflection characteristic having wavelength selectivity. However, both may have the same wavelength selectivity for reflection characteristics.
[0106]
Embodiment 9 FIG.
FIG. 12 is a perspective view showing a configuration of an optical waveguide according to the ninth embodiment of the present invention. In the figure, the same reference numerals as those in FIGS. 1 and 11 denote the same or corresponding parts. In the ninth embodiment, the first multilayer mirror 4a formed on the inclined end face F1 of the first optical fiber, and the second multilayer mirror 4b formed on the inclined end face F2 of the second optical fiber, However, the present embodiment is different from Embodiment 8 in that the reflection characteristics have different wavelength selectivity.
[0107]
For example, the first multilayer mirror 4a totally reflects incident light having a wavelength equal to or longer than the first wavelength λ1, and the second multilayer mirror 4b has a second wavelength larger than the first wavelength λ1. It is assumed that incident light having a wavelength of λ2 or less is totally reflected.
[0108]
In the optical waveguide configured as described above, when a light beam having a wavelength shorter than the first wavelength λ1 is incident on one optical fiber, the incident light beam passes through the first multilayer mirror 4a. Therefore, it is not transmitted to other optical fibers. Further, when a light beam having a wavelength longer than the second wavelength λ2 is incident on one of the optical fibers, the incident light beam passes through the second multilayer mirror 4b, and the other optical fiber. Is not communicated to. Then, when a light beam having a wavelength in the band from the first wavelength λ1 to the second wavelength λ2 is incident, the incident light beam is converted into the first multilayer film mirror 4a and the second multilayer film mirror 4b. Is totally reflected and transmitted to another optical fiber. For this reason, it can be used as a band pass filter. Further, in this optical waveguide, instead of the light beam emitted from the other optical fiber, the light beams emitted from the first multilayer mirror 4a and the second multilayer mirror 4b are output, This optical waveguide can be used as a band rejection filter.
[0109]
Embodiment 10 FIG.
13A and 13B are diagrams showing the configuration of the optical waveguide according to the tenth embodiment of the present invention. FIG. 13A is a perspective view, FIG. 13B is an A arrow view of FIG. c) is an arrow B view of FIG. 13 (a). In the figure, the same reference numerals as those in FIG. 1 denote the same or corresponding parts, and the optical waveguide according to the tenth embodiment includes the first and second optical fibers in addition to the first and second optical fibers Of1 and Of2. A third optical fiber Of3 having the same structure as the fibers Of1 and Of2 and having an inclined end face F3 inclined at 45 degrees with respect to the central axis Ax7 at one end thereof; The central axis Ax7 of the third optical fiber Of3 coincides with the central axis Ax1 of the first optical fiber, and the inclined end face F3 of the third optical fiber is substantially the same as the inclined end face F1 of the first optical fiber. This is different from the first embodiment in that they are arranged so as to be parallel and have a predetermined interval S. P1 to P3 indicate first to third ports that are the other ends of the first to third optical fibers Of1 to Of3.
[0110]
Next, the operation of the thus configured optical waveguide will be described.
First, when the light beam is incident from the first port P1, a part of the incident light beam passes through the inclined end surface F1 and the inclined end surface F3 at a ratio corresponding to the interval S between the inclined end surface F1 and the inclined end surface F3. Then, the light enters the third optical fiber Of3 and is emitted from the third port P3, and the other is reflected by the inclined end face F1, passes through the second optical fiber Of2, and is emitted from the second port P2. As a result, it functions as an optical demultiplexer.
[0111]
On the other hand, when the light beams are respectively incident from the second port P2 and the third port P3, the two incident light beams are combined at the inclined end face F1 of the first optical fiber and are incident on the first optical fiber. Incident light is emitted from the first port P1. As a result, it functions as an optical multiplexer.
[0112]
Therefore, according to the tenth embodiment, it is possible to provide an optical waveguide that can multiplex and demultiplex a light beam and can route an optical wiring in a T shape with high coupling efficiency.
[0113]
Embodiment 11 FIG.
14A and 14B are diagrams showing a configuration of an optical waveguide according to the eleventh embodiment of the present invention, in which FIG. 14A is a perspective view, FIG. 14B is a view shown by an arrow A in FIG. c) is a view as indicated by an arrow B in FIG.
[0114]
In the figure, the same reference numerals as those in FIG. 1 denote the same or corresponding parts, and the optical waveguide according to the tenth embodiment is different from the optical waveguide according to the tenth embodiment in the following points. That is, in addition to the first to third optical fibers Of1 to Of3, it has the same structure as the first to third optical fibers Of1 to Of3, and its one end is inclined by 45 degrees with respect to the central axis Ax8. The optical fiber further includes a fourth optical fiber Of4 having an inclined end face F4. The third optical fiber Of3 is different from the third optical fiber Of3 in that the center Cp4 of the inclined end face F4 of the fourth optical fiber Of4 is Third optical fiber / fourth optical fiber orthogonal to the central axis Ax7 of the third optical fiber Of3 with the center axis Ax10 of the inclined end face F3 sandwiched by the center Cp3 of the inclined end face F3 of the third optical fiber Of3 The third optical fiber / fourth light is positioned on the orthogonal axis Ax9 so that the central axis Ax8 of the fourth optical fiber Of4 sandwiches the central axis Ax11 of the inclined end face F4 of the fourth optical fiber Of4. A crossing angle of 90 degrees with respect to the central axis Ax7 of the third optical fiber Of3 when viewed from the direction of the third optical fiber / fourth optical fiber orthogonal axis Ax9 and orthogonal to the fiber orthogonal axis Ax9, The inclined end face F3 of the optical fiber Of3 and the inclined end face F4 of the fourth optical fiber Of4 are directed in directions opposite to each other when viewed from the third optical fiber / fourth optical fiber orthogonal axis Ax9 direction, and The fourth optical fiber Of4 and the third optical fiber Of3 are arranged so that the distance satisfying the condition that the coupling efficiency η described in the first embodiment is 1 (zero in the illustrated example). P4 is a fourth port which is the other end of the fourth optical fiber Of4.
[0115]
Here, as shown in FIG. 14 (c), since the inclined end face F1 of the first optical fiber and the inclined end face F3 of the third optical fiber have a predetermined interval S, the first light Although the fiber / second optical fiber orthogonal axis Ax3 does not coincide with the third optical fiber / fourth optical fiber orthogonal axis Ax9, the predetermined interval S is a spot of the first to fourth optical fibers Of1 to Of4. Since it is very small compared to the size, when analyzing the reflection or transmission of the light beam at the inclined end faces F1 to F4, the first optical fiber / second optical fiber orthogonal axis Ax3 and the third optical fiber / second optical fiber are analyzed. The four optical fiber orthogonal axes Ax9 can be regarded as coincident.
[0116]
Next, the operation of the optical waveguide configured as described above will be described.
First, when a light beam is incident from the first port P1, the incident light beam is distributed by the inclined end surface F1 and the inclined end surface F3, and is output from the second port P2 and the third port P3. Further, when a light beam is incident from the second port P2, the incident light beam is distributed by the inclined end surface F1 and the inclined end surface F3, and is output from the first port P1 and the fourth port P4. Similarly, the light beam incident from the third port P3 is distributed at the inclined end surface F3 and the inclined end surface F1, and is output from the fourth port P4 and the first port P1, and is output from the fourth port P4. The incident light beam is distributed by the inclined end face F3 and the inclined end face F1, and is output from the third port P3 and the second port P2.
[0117]
Therefore, according to the optical waveguide according to the eleventh embodiment, any of the four ports P1 to P4 can be used as an input port for demultiplexing.
[0118]
Embodiment 12 FIG.
15A and 15B are diagrams showing a configuration of an optical waveguide according to the twelfth embodiment of the present invention, in which FIG. 15A is a perspective view, FIG. 15B is an A arrow view of FIG. c) is a view as indicated by an arrow B in FIG. In the figure, the same reference numerals as those in FIG. 6 denote the same or corresponding parts, and the optical waveguide according to the twelfth embodiment includes the first optical fiber Of1, the second optical fiber Of2 and the rod lens 100 in addition to the first optical fiber. , Further including a third optical fiber Of3 having the same structure as the second optical fibers Of1, Of2, and having an inclined end face F3 inclined at 45 ° with respect to the central axis Ax7 at one end thereof. In the optical fiber Of3, the central axis Ax7 of the third optical fiber Of3 coincides with the central axis Ax1 of the first optical fiber, and the inclined end face F3 of the third optical fiber is inclined with respect to the first optical fiber. The optical waveguide according to the second embodiment is different from the optical waveguide according to the second embodiment in that it is arranged so as to be substantially parallel to the end face F1 and to have a predetermined interval S. P1 to P3 indicate first to third ports that are the other ends of the first to third optical fibers Of1 to Of3.
[0119]
Next, the operation of the thus configured optical waveguide will be described.
First, when the light beam is incident from the first port P1, a part of the incident light beam passes through the inclined end surface F1 and the inclined end surface F3 at a ratio corresponding to the interval S between the inclined end surface F1 and the inclined end surface F3. Then, the light enters the third optical fiber Of3 and is emitted from the third port P3, and the other is reflected by the inclined end face F1, passes through the second optical fiber Of2, and is emitted from the second port P2. As a result, it functions as an optical demultiplexer.
[0120]
On the other hand, when the light beams are respectively incident from the second port P2 and the third port P3, the two incident light beams are combined at the inclined end face F1 of the first optical fiber Of1, and the first optical fiber is combined. The light enters the Of1 and exits from the first port P1. As a result, it functions as an optical multiplexer.
[0121]
Therefore, according to the twelfth embodiment, it is possible to provide an optical waveguide that can multiplex / demultiplex a light beam and can route an optical wiring in an h shape in the same plane with high coupling efficiency. it can.
[0122]
Embodiment 13 FIG.
16A and 16B are diagrams showing the configuration of the optical waveguide according to the thirteenth embodiment of the present invention, in which FIG. 16A is a perspective view, FIG. 16B is a view shown by an arrow A in FIG. c) is a view as indicated by an arrow B in FIG. In the figure, the same reference numerals as those in FIG. 7 denote the same or corresponding parts, and the optical waveguide according to the thirteenth embodiment includes the first optical fiber Of1, the second optical fiber Of2 and the rod lens 100 in addition to the first optical fiber. , Further including a third optical fiber Of3 having the same structure as the second optical fibers Of1, Of2, and having an inclined end face F3 inclined at 45 ° with respect to the central axis Ax7 at one end thereof. In the optical fiber Of3, the center axis Ax7 of the third optical fiber Of3 coincides with the center axis Ax1 of the first optical fiber, and the inclined end face F3 of the third optical fiber is aligned with the first optical fiber Of1. The optical waveguide according to the third embodiment is different from the optical waveguide according to the third embodiment in that it is arranged so as to be substantially parallel to the inclined end face F1 and to have a predetermined interval S. P1 to P3 indicate first to third ports that are the other ends of the first to third optical fibers Of1 to Of3.
[0123]
In the optical waveguide configured as described above, when the light beam is incident from the first port P1, the incident light beam is partially inclined at the ratio according to the interval S between the inclined end surface F1 and the inclined end surface F3. F1 and the inclined end face F3 are incident on the third optical fiber Of3, emitted from the third port P3, and the others are reflected by the inclined end face F1 and pass through the second optical fiber Of2, and then the second port. It is emitted from P2. On the other hand, when the light beams are incident from the second port P2 and the third port P3, the two incident light beams are combined at the inclined end face F1 of the first optical fiber, and the first optical fiber Of1. And exits from the first port P1.
[0124]
Therefore, according to the thirteenth embodiment, it is possible to provide an optical waveguide that can multiplex / demultiplex a light beam and that can route an optical wiring in an h shape in the same plane with high coupling efficiency. it can.
[0125]
Embodiment 14 FIG.
FIG. 17 is a diagram showing the position of the inclined end face of the optical fiber in the optical waveguide according to the fourteenth embodiment of the present invention.
In the figure, the same reference numerals as those in FIG. 1 denote the same or corresponding parts, and the fourteenth embodiment is different from the first embodiment in the following points.
That is, Cp1 ′ is a Goose Henschen shift Z with respect to light propagating through the center of the first optical fiber Of1._GHThe apparent reflection point F1 ′ by F1 ′ is a virtual inclined end surface having the apparent reflection point Cp1 ′ at the center and parallel to the inclined end surface F1 of the first optical fiber Of1, and Ax5 ′ is the virtual inclination. The central axis of end face F1 'is shown. In the fourteenth embodiment, the first optical fiber Of1 is centered so that the virtual inclined end face F1 ′ is located at the position where the inclined end face F1 of the first optical fiber Of1 exists in the optical waveguide of FIG. They are shifted by a distance L in the direction of the axis Ax1.
[0126]
Similarly to the first optical fiber Of1, the second optical fiber Of2 also has the virtual inclined end face of the second optical fiber Of2, and the inclined end face F2 of the second optical fiber Of2 in the optical waveguide of FIG. It is arranged so as to be shifted by a distance L in the direction of the central axis Ax2 so as to be located at an existing position (not shown).
[0127]
Next, in the optical waveguide configured as described above, when the light beam propagates through the connection portion between the first optical fiber Of1 and the second optical fiber Of2, the inclined end face F1 of the first optical fiber, and Since the deviation of the reflection point due to the Goose Henschen shift on the inclined end face F2 of the second optical fiber is corrected, it is possible to prevent the coupling efficiency from being lowered due to the deviation of the reflection point.
[0128]
In Embodiments 2 to 5, the same effects as described above can be obtained by configuring in the same manner as described above.
[0129]
Embodiment 15 FIG.
18A and 18B are diagrams showing the configuration of the optical multiplexer / demultiplexer according to the fifteenth embodiment of the present invention. FIG. 18A is a front view, and FIG. 18B is a diagram indicated by arrow C in FIG. . In the figure, the same reference numerals as those in FIG. 13 denote the same or corresponding parts, and the optical multiplexer / demultiplexer according to the fifteenth embodiment is connected to the third optical fiber Of3 of the optical waveguide according to the tenth embodiment. It is configured to be movable in the direction of the central axis Ax7 of the fiber Of3.
[0130]
In the optical multiplexer / demultiplexer configured as described above, when the inclined end face F3 of the third optical fiber is located at an infinite distance from the inclined end face F1 of the first optical fiber, the light enters the first port P1. All the light beams are output to the second port P2. Further, when the inclined end face F3 of the third optical fiber is brought into contact with the inclined end face F1 of the first optical fiber, all light beams incident from the first port P1 are output to the second port P2. When the inclined end face F3 of the third optical fiber is positioned so as to have a certain distance S with respect to the inclined end face F1 of the first optical fiber, the light beam incident from the first port P1 is the distance. A part is output to the second port P2 at a ratio corresponding to S, and the other is output to the third port P3.
[0131]
Further, the inclined end face F3 of the third optical fiber is positioned at an infinite distance from the inclined end face F1 of the first optical fiber, and light beams are incident from the second port P2 and the third port P3, respectively. As a result, all the light beams incident from the third port P3 are reflected by the inclined end surface F3 of the third optical fiber, and only the light beams incident from the second port P2 are all reflected. 1 port P1. When the inclined end face F3 of the third optical fiber is brought into contact with the inclined end face F1 of the first optical fiber and the light beams are incident from the second port P2 and the third port P3, respectively, All the light beams incident from the port P2 pass through the inclined end surface F1 of the first optical fiber and the inclined end surface F3 of the third optical fiber, and only the light beam incident from the third port P2 is used. Are all output to the first port P1. Then, the inclined end face F3 of the third optical fiber is positioned so as to have a certain distance S with respect to the inclined end face F1 of the first optical fiber, and light is transmitted from the second port P2 and the third port P3, respectively. When the beams are incident, the two incident light beams are combined at a ratio corresponding to the interval S and output to the first port P3.
[0132]
In the above description, the third optical fiber Of3 is movable to change the distance S between the inclined end face F3 of the third optical fiber and the inclined end face F1 of the first optical fiber. The first and second optical fibers Of1, Of2 may be movable.
[0133]
As described above, according to the optical multiplexer / demultiplexer of the fifteenth embodiment, by changing the distance S between the inclined end face F3 of the third optical fiber and the inclined end face F1 of the first optical fiber, the distance In accordance with S, the distribution ratio when the light beam incident from the first port P1 is output to the second port P2 and the third port P3, and the second port P2 and the third port Since the combination ratio when the light beams respectively incident from P3 are output to the first port P1 changes, it can be used as a variable optical multiplexer / demultiplexer.
[0134]
Embodiment 16 FIG.
FIG. 19 is a diagram showing a configuration of an optical multiplexer / demultiplexer according to Embodiment 16 of the present invention. In the figure, the same reference numerals as those in FIG. 13 denote the same or corresponding parts, and the optical multiplexer / demultiplexer according to the sixteenth embodiment has the inclined end face F1 and the first end of the first optical fiber Of1 of the optical waveguide according to the tenth embodiment. The wavelength selective filter 5 is inserted in the gap with the inclined end face F3 of the optical fiber Of1.
[0135]
For example, the wavelength selection filter 5 transmits light having a wavelength of λ0 or more and reflects light having a wavelength of less than the wavelength λ0.
[0136]
In the optical multiplexer / demultiplexer configured as described above, when a light beam composed of light having a wavelength λ1 smaller than the wavelength λ0 and light having a wavelength λ2 larger than the wavelength λ0 is incident from the first port P1, Of the incident light beam, the light having the wavelength λ 1 is reflected by the wavelength selection filter 5 and output to the second port P 2, and the light having the wavelength λ 2 is transmitted through the wavelength selection filter 5 and passes through the third port. Since it is output to P3, the incident light beam is wavelength-divided.
[0137]
Therefore, according to the sixteenth embodiment, an optical multiplexer / demultiplexer capable of wavelength division can be provided.
[0138]
Embodiment 17. FIG.
The seventeenth embodiment of the present invention is an optical parallel bus by arranging a plurality of optical waveguides of the tenth embodiment in parallel.
[0139]
20A and 20B are diagrams showing the configuration of the optical parallel bus according to the seventeenth embodiment, in which FIG. 20A is a top view and FIG. 20B is a view as indicated by an arrow E in FIG. In the figure, the same reference numerals as in FIG. 1 denote the same or corresponding parts, Bu is an optical parallel bus composed of a first optical parallel bus Bu1 and a second optical parallel bus Bu2, 6 is an optical fiber fixing groove, 7 Is a substrate.
[0140]
The first optical parallel bus Bu1 is composed of the same number (four in each of the seventeenth embodiment) of the first optical fibers Of1, and the third optical fibers Of3. The first optical fibers Of1, The third optical fiber Of3 is held by an optical fiber fixing groove 6 having a V-shaped cross section formed in parallel on the upper surface of the substrate 7. Therefore, the central axis Ax1 of the first optical fiber and the central axis Ax7 of the third optical fiber are parallel to each other and are all located in the same plane. In the four first optical fibers Of1, the planes including the central axis Ax1 of each first optical fiber Of1 and the central axis of the inclined end face F1 are all perpendicular to the plane, and the first optical fibers Of1. The inclined end faces F1 are all oriented in the same direction (downward in the figure), and the inclined end faces F1 of the first optical fibers are arranged so as not to overlap each other when viewed from the arrangement direction of the first optical fibers Of1. The third optical fiber Of3 corresponds to the four first optical fibers Of1 on a one-to-one basis, and the central axis Ax7 of the third optical fiber Of3 corresponds to the corresponding first optical fiber. The inclined end surface F3 of the third optical fiber Of3 coincides with the inclined end surface F1 of the corresponding first optical fiber Of1 at a predetermined interval so as to coincide with the central axis Ax1 of Of1. .
[0141]
The second optical parallel bus Bu2 is composed of four second optical fibers Of2, and these four second optical fibers Of2 are composed of the first optical fiber Of1, the third optical fiber Of3 and the second optical fiber Of2. Similarly, the substrates (not shown) are held parallel to each other so that the central axes Ax2 are all located in the same plane. The four second optical fibers Of2 correspond to the four first optical fibers Of1 on a one-to-one basis, and the center of the inclined end face F2 of each second optical fiber is set to the first first optical fiber Of1. On the first optical fiber / second optical fiber orthogonal axis orthogonal to the central axis Ax1 of each first optical fiber so as to sandwich the central axis of the inclined end face F1 at the center of the inclined end face F1 of the first optical fiber And the center axes Ax2 of the respective second optical fibers are parallel to each other and all lie in the same plane, and the first optical fibers / spindles sandwich the central axis of the inclined end face F2 of each second optical fiber. The crossing angle is 90 degrees with respect to the central axis Ax1 of each first optical fiber when viewed from the direction of each first optical fiber / second optical fiber orthogonal axis and orthogonal to the second optical fiber orthogonal axis. The inclined end face F1 of each first optical fiber and each second optical fiber The inclined end face F2 of the fiber faces in directions opposite to each other when viewed from the first optical fiber / second fiber orthogonal axis direction, and each second optical fiber Of2 and each first optical fiber Of1 are It is arranged to touch.
[0142]
The first optical fiber Of1, the second optical fiber Of2, and the third optical fiber Of3 are selected so that the refractive index of each inclined end face satisfies the total reflection condition, as in the first embodiment, The parameter α is selected such that the coupling efficiency is 1 when the first optical fiber Of1 and the second optical fiber Of2 are in contact with each other, and the tilted end face F1 of the first optical fiber and the tilt of the third optical fiber are selected. The predetermined distance from the end face F3 is selected so that the reflectance at the inclined end face F1 of the first optical fiber becomes a predetermined value (for example, 0.5).
[0143]
In the optical parallel bus configured as described above, when a light beam is incident on an arbitrary first optical fiber Of1 of the first optical parallel bus Bu1, the incident light beam is converted into the first optical fiber Of1. Are distributed to the second optical fiber Of2 at a ratio corresponding to the predetermined reflectance at the inclined end face F1, and the arbitrary third optical fiber Of3 of the first optical parallel bus Bu1 and the arbitrary third light are distributed. When a light beam is incident on the third optical fiber Of3 of the second optical parallel bus Bu2 corresponding to the fiber Of3, the incident light beam is reflected on the inclined end face F1 of the first optical fiber by the predetermined reflection. The signals are combined at a rate based on the rate and output to the first optical fiber Of1.
[0144]
As described above, according to the optical parallel bus of the seventeenth embodiment, the first optical parallel bus Bu1 in which a plurality of first optical fibers Of1 and third optical fibers Of3 are arranged in parallel and in a planar shape. The second optical parallel bus Bu2 in which the second optical fibers Of2 corresponding to the first optical fibers Of1 in a one-to-one correspondence are arranged in a plane parallel to each other is an inclined end face F1 as viewed from the arrangement direction. For each of the first optical fibers Of1 arranged so as not to overlap, both the second optical fibers Of2 are both viewed from the direction perpendicular to the arrangement plane of the first and second optical fibers Of1, Of2. The inclined end faces F1 and F2 overlap each other at right angles so that the third optical fibers Of3 are connected to each other so as to be positioned on the extension of the first optical fiber Of1 with a predetermined interval. So each optical parallel bus u1, optical fibers constituting the Bu2 Of1, OF3, Of 2 it is possible to arrange close to each other, it is possible to save the wiring space. In addition, since each first optical fiber Of1 and each second optical fiber Of2 form an optical waveguide according to the first embodiment, the coupling efficiency is 1, and the efficiency is high.
[0145]
Embodiment 18 FIG.
The eighteenth embodiment of the present invention exemplifies an optoelectronic integrated device in which the optical waveguide of the first embodiment is used for a connection portion between an EO chip and an EO board.
[0146]
FIG. 21 is a perspective view showing the configuration of the optoelectronic integrated apparatus according to the eighteenth embodiment. In the figure, the same reference numerals as those in FIG.
[0147]
The EO chip 11 has an optoelectronic circuit including an electronic element and an optical element therein, and a plurality of electrode pins whose base ends are electrically connected to the optoelectronic circuit on the lower surface of the EO chip 11. (Chip-side contact electrode) 16 and a plurality of (four in the figure) having a base end optically connected to the optoelectronic circuit, an inclined end face F1 at the tip, and a predetermined length A first optical fiber (chip-side optical connecting means) Of1 is projected downward. Further, a positioning convex portion 18 having a rectangular parallelepiped shape is projected from the lower surface of the EO chip 11.
[0148]
The EO board 14 includes an E board layer 12 disposed on the upper side and an O board layer 13 disposed on the lower side. In the region where the EO chip 11 is mounted on the upper surface of the EO board 14, the EO chip 11 is disposed. The positioning concave portion 19 and the electrode hole (board-side contact electrode) 17 are respectively provided at positions corresponding to the positioning convex portion 18 and the electrode pin 16, and the first optical fiber Of1 of the EO chip 11 is provided. The optical fiber insertion hole 15 is recessed at a position corresponding to. Further, a lever 20 for fixing the EO chip 11 is disposed on the upper surface of the EO board 14.
[0149]
The positioning concave portion 19 has a rectangular parallelepiped shape that fits into the positioning convex portion 18 of the EO chip 11.
[0150]
The electrode hole 17 has a shape that fits into the electrode pin 16 of the EO chip 11, and an electrode connected to the electric wiring of the E board layer 12 is disposed on the inner surface.
[0151]
The optical fiber insertion hole 15 is formed to have a depth that penetrates the E board layer 12 and reaches the middle of the thickness of the O board layer 13, and is formed in the O board layer 13 of the optical fiber insertion hole 15. Four second optical fibers (board side light) having a base end connected to the optical wiring of the O-board layer 13 and an inclined end surface F2 at the tip and having a predetermined length are formed on the inner surface of the portion. Connecting means) Of2 is projected in the horizontal direction.
[0152]
The four second optical fibers Of2 are provided so as to correspond to the four first optical fibers Of1 on a one-to-one basis, and the one-to-one corresponding second optical fibers Of2 and the first light are provided. The pair of fibers Of1 are arranged so that the coupling efficiency described in the first embodiment is 1 when the EO chip 11 is mounted on the EO board 14.
[0153]
That is, when the EO chip 11 is mounted on the EO board 14, the pair of the second optical fiber Of2 and the first optical fiber Of1, the center of the inclined end face F2 of each second optical fiber Of2 is Each first optical fiber / second optical fiber orthogonal to each center of the first optical fiber Of1 perpendicular to the center axis of the first optical fiber Of1 with the central axis of the inclined end surface F1 sandwiched between the centers of the inclined end surfaces F1 of the first optical fibers Of1. The center axis of each second optical fiber Of2 is positioned on the axis so that the center axis of the inclined end face F2 of each second optical fiber is sandwiched between the first optical fiber / second optical fiber orthogonal axis. Each of the first optical fibers has a crossing angle of 90 degrees with respect to the central axis of each first optical fiber when viewed from the direction perpendicular to each first optical fiber / second optical fiber. End face F1 and each second optical fiber The inclined end face F2 faces opposite directions when viewed from the first optical fiber / second fiber orthogonal axis direction, and the second optical fibers Of2 and the first optical fibers Of2 are in contact with each other. Are arranged to be.
[0154]
The first optical fiber Of1 and the second optical fiber Of2 are selected so that the refractive indexes of the inclined end faces F1 and F2 satisfy the total reflection condition, as in the first embodiment, and the parameter α is The coupling efficiency is selected to be 1 when the first optical fiber Of1 and the second optical fiber Of2 come into contact with each other.
[0155]
The lever 20 protrudes on both side surfaces of a plate-shaped pressing portion 22 having a rounded tip, a rod-like operation portion 21 protruding from a part of the tip of the pressing portion 22, and a base of the pressing portion 22. And a support member 24 that is disposed on the upper surface of the EO board 14 and rotatably holds the rotation shaft 23 of the pressing portion 22. The support member 24 is configured so that the pressing member 22 is in a horizontal state. At that time, the EO chip 11 mounted on the EO board 14 is pressed by the tip of the pressing member 22, so that the positioning convex portion 18 of the EO chip 11 becomes the position of the positioning concave portion 19 of the EO board 14. It is installed at a position where it can be pressed against the inner wall in the pressing direction (arrow direction in the figure). The positions of the electrode holes 17 of the EO board 14 and the second optical fiber Of2 are such that the positioning projection 18 of the EO chip 11 is on the inner wall in the pressing direction of the positioning recess 19 of the EO board 14 as described above. When pressed, the electrode pins 16 of the EO chip 11 and the first optical fibers Of1 are respectively placed on the side walls of the electrode holes 17 in the pressing direction and the side surfaces of the second optical fibers Of2. Just set to touch.
[0156]
Next, the operation of the optoelectronic integrated device 10 configured as described above will be described.
First, in order to mount the EO chip 11 on the EO board 14, the operation unit 21 is pulled to raise the lever 20 in a vertical state. Next, the positioning convex portion 18, the electrode pin 16, and the first optical fiber Of1 of the EO chip 11 are respectively inserted into the positioning concave portion 19, the electrode hole 17, and the optical fiber insertion hole 15 of the EO board 14. In this manner, the EO chip 11 is attached to the EO board 14. Next, the operation unit 21 is pressed to tilt the lever 20 to a horizontal state. Then, the EO chip 11 is pressed in the direction of the arrow by the pressing portion 22 of the lever 20, and the positioning convex portion 18 is pressed and fixed to the inner wall of the positioning concave portion 19 of the EO board 14 in the pressing direction. The electrode pin 16 and the first optical fiber Of1 are in contact with the side wall of the electrode hole 17 of the EO board 14 in the pressing direction and the side surface of the second optical fiber Of2. As a result, the EO chip 11 is mounted on the EO board 14, the electrode pins 16 and the electrode holes 17 are electrically connected, and the first optical fiber Of1 and the second optical fiber Of2 are optically connected. .
[0157]
Next, in order to remove the EO chip 11 from the EO board 14, the operation unit 21 is pulled from the above state to raise the lever 20 to a vertical state, and the EO chip 11 is pulled out from the board 14. As a result, the EO chip 11 is removed from the EO board 14.
[0158]
In the above description, when the EO chip 11 is mounted on the EO board 14, the first optical fiber Of1 and the second optical fiber Of2 are in contact with each other, but the first optical fiber Of1 and You may make it have a predetermined space | interval with 2nd optical fiber Of2.
[0159]
In the above description, the first optical fiber Of1 is projected from the lower surface of the EO chip 11. However, the first optical fiber Of1 may be projected from the outside so as to be in contact with the EO chip 11.
[0160]
In the above description, the second optical fiber Of2 is projected on the inner wall surface of the optical fiber insertion hole 15 that is recessed in the EO board 14, but the first optical fiber Of1 and a predetermined positional relationship are provided. What is necessary is just to project to the EO board 14 so that it may become.
[0161]
As described above, in the eighteenth embodiment, when the EO chip 11 is mounted at a predetermined position on the EO board 14, the first optical fiber Of1 as the chip-side optical connection means of the EO chip 11 and the EO Since the second optical fiber Of2 as the board-side optical connecting means of the board 14 forms the optical waveguide according to the first embodiment, the coupling efficiency is 1, and the EO chip 11 and the EO board 14 are optically efficient. Connected. Further, the first optical fiber Of1 and the second first optical fiber Of2 are optically connected when their distal ends come into contact with each other or at a predetermined interval. The EO board 14 can be easily optically connected, and the configuration of the connecting portion is simple.
[0162]
In Embodiments 2 to 18 above, the crossing angle between the first and second optical fibers Of1, Of2 and the first optical fiber / second optical fiber orthogonal axis Ax3, the first optical fiber Of1 and the first optical fiber Of1. Crossing angle between the second optical fiber Of2, the crossing angle between the third and fourth optical fibers Of3, Of4 and the third optical fiber / fourth optical fiber orthogonal axis Ax9, the first optical fiber Of1 and the second optical fiber Of2. The optical fiber Of2 crossing angle, the inclined angles F1 and F2 of the optical fibers Of1 and Of2, and the optical fiber spacing d are assumed to be ideal values. The value can be set in accordance with the required coupling efficiency within a range close to the ideal value.
[0163]
In Embodiments 10 to 13 and 15 to 17, the inclined end face F1 of the first optical fiber and the inclined end face F3 of the third optical fiber are parallel to each other. .
[0164]
In Embodiments 2 to 18 described above, an optical fiber composed of the core 1 and the clad 2 is used as the optical waveguide member, but the refractive index is changed so as to gradually decrease in the radial direction. A lens may be used.
[0165]
In Embodiments 2 to 18, the optical waveguide member has a constant diameter in the central axis direction. However, the optical waveguide member may have a diameter that changes in the central axis direction.
[0166]
In the eighteenth embodiment, when the EO chip 11 is mounted on the EO board 14, the first optical fiber Of1 of the EO chip 11 and the second optical fiber Of2 of the EO board 14 are the optical waveguide of the first embodiment. However, the present invention is not limited to this, and when the EO chip 11 is mounted on the EO board 14, the optical waveguide member of the EO chip 11 and the optical waveguide member of the EO board 14, or the optical waveguide member and the rod lens member However, you may make it form the waveguide of Embodiment 2-5, or the waveguide of Embodiment 10-13.
[0167]
In the above embodiments 15 to 18, the case where the optical waveguide of the present invention is applied to an optical multiplexer / demultiplexer, an optical parallel bus, and an optoelectronic integrated device is shown. The optical waveguide member can be widely applied to applications that require connection between optical waveguide members. For example, the optical waveguide member is wired on the backplane of the EO board, and the optical waveguide member protrudes from the EO board. Is inserted into the backplane, the optical waveguide member protruding from the EO board and the optical waveguide member wired to the backplane are connected to the waveguides of the second to fifth embodiments or the waveguides of the tenth to thirteenth embodiments. A waveguide can be formed.
[0168]
【The invention's effect】
As described above, according to the optical waveguide of the first aspect of the present invention, when a light beam is incident on one optical waveguide member, the incident light beam is centered on the inclined end surface of the one optical waveguide member. Is totally reflected on the first optical waveguide member, travels along the orthogonal axis of the first optical waveguide member / second optical waveguide member, and is totally reflected on the central portion of the inclined end surface of the other optical waveguide member. Propagating along the central axis, at this time, the light beams reflected by the center of the inclined end surface of one of the optical waveguide members and having an expanded diameter are in a positional relationship where the two optical waveguide members are twisted by approximately 90 ° from each other. The side surface receives a substantially uniform convergence effect in the cross-sectional direction of the light beam, and at the center of the inclined end surface of the other optical waveguide member, the diameter is approximately the same as the diameter when the light beam propagates through the other optical waveguide member. Therefore, it is reflected by the inclined end surface of the other optical waveguide member. Substantially all of the light beam becomes to be incident on a portion of propagating light beam of the other side of the optical waveguide member, the coupling efficiency between Ryohikarishirubeha member is substantially 1. For this reason, the optical wiring can be routed in a right angle direction with high coupling efficiency.
[0169]
  According to the optical waveguide of the second aspect of the invention, the first optical waveguide member is inclined according to the distance between the inclined end surface of the first optical waveguide member and the inclined end surface of the third optical waveguide member. Since the reflectance at the end face changes, when the light beam is incident from the first optical waveguide member by appropriately setting the interval, the incident light beam is converted into the first optical waveguide member. When the light beam is incident from the second and third optical waveguide members after being split at a predetermined ratio at the inclined end surface of the optical system, the light beams are incident on the second and third optical waveguide members. The two light beams are combined at a predetermined ratio on the inclined end surface of the first optical waveguide member and enter the first optical waveguide member. Therefore, it is possible to provide an optical waveguide that can multiplex / demultiplex light beams and that can route optical wiring in a T-shape with high coupling efficiency..
[0170]
According to the optical waveguide of the invention of claim 3, since the distance between the first optical waveguide member and the third optical waveguide member is very small, the first optical waveguide member / second optical waveguide member Since the optical waveguide member orthogonal axis substantially coincides with the third optical waveguide member / fourth optical waveguide member orthogonal axis, the light beam incident on the first optical waveguide member is the same as the second optical waveguide member and the second optical waveguide member. The light beam distributed to the third optical waveguide member and incident on the second optical waveguide member is distributed to the first optical waveguide member and the fourth optical waveguide member, and incident on the third optical waveguide member. The caulked light beam is distributed to the fourth optical waveguide member and the first optical waveguide member, and the light beam incident on the fourth optical waveguide member is the third optical waveguide member and the second optical waveguide. Distributed to the member. Therefore, it is possible to provide an optical waveguide capable of demultiplexing a light beam regardless of which of the four optical waveguide members is used as an input port.
[0171]
According to the optical waveguide of the invention of claim 4, when the light beam is incident on one of the optical waveguide members, the incident light beam is entirely at the central portion of the inclined end surface of the one optical waveguide member. Reflected, travels along the first optical waveguide member / second optical waveguide member orthogonal axis, is totally reflected at the central portion of the inclined end surface of the other optical waveguide member, and is reflected on the central axis of the other optical waveguide member In this case, the one light waveguide member and the rod lens in which the light beams whose diameters are expanded by being reflected at the center of the inclined end surface of one of the light waveguide members are in a positional relationship twisted by approximately 90 ° with respect to each other. The side surface of the member and the side surface of the rod lens member and the other optical waveguide member receive a substantially uniform convergence effect in the cross-sectional direction of the light beam, and at the center of the inclined end surface of the other optical waveguide member, the other optical waveguide Approximately the same diameter as the light beam propagates through the member Since it has a diameter, almost all of the light beam reflected by the inclined end surface of the other optical waveguide member is incident on the portion of the other optical waveguide member that propagates the light beam. The coupling efficiency between them is approximately 1. For this reason, the optical wiring can be routed in a U-shape in the same plane with high coupling efficiency.
[0172]
  According to the optical waveguide of the fifth aspect of the invention, the first optical waveguide member is inclined according to the distance between the inclined end surface of the first optical waveguide member and the inclined end surface of the third optical waveguide member. Since the reflectance at the end face changes, when the light beam is incident from the first optical waveguide member by appropriately setting the interval, the incident light beam is converted into the first optical waveguide member. When the light beam is incident from the second and third optical waveguide members after being split at a predetermined ratio at the inclined end surface of the optical system, the light beams are incident on the second and third optical waveguide members. The two light beams are combined at a predetermined ratio on the inclined end surface of the first optical waveguide member and enter the first optical waveguide member. Therefore, it is possible to provide an optical waveguide that can multiplex / demultiplex the light beam and that can route the optical wiring in the shape of h in the same plane with high coupling efficiency..
[0173]
According to the optical waveguide of the sixth aspect of the present invention, when a light beam is incident on one of the optical waveguide members, the incident light beam is entirely at the central portion of the inclined end surface of the one optical waveguide member. Reflected, travels along the first optical waveguide member / second optical waveguide member orthogonal axis, is totally reflected at the central portion of the inclined end surface of the other optical waveguide member, and is reflected on the central axis of the other optical waveguide member In this case, the one light waveguide member and the rod lens in which the light beams whose diameters are expanded by being reflected at the center of the inclined end surface of one of the light waveguide members are in a positional relationship twisted by approximately 90 ° with respect to each other. The side surface of the member and the side surface of the rod lens member and the other optical waveguide member receive a substantially uniform convergence effect in the cross-sectional direction of the light beam, and at the center of the inclined end surface of the other optical waveguide member, the other optical waveguide Approximately the same diameter as the light beam propagates through the member Since it has a diameter, almost all of the light beam reflected by the inclined end surface of the other optical waveguide member is incident on the portion of the other optical waveguide member that propagates the light beam. The coupling efficiency between them is approximately 1. For this reason, the optical wiring can be routed in an S shape with high coupling efficiency.
[0174]
  According to the optical waveguide of the seventh aspect of the invention, the first optical waveguide member is inclined according to the distance between the inclined end surface of the first optical waveguide member and the inclined end surface of the third optical waveguide member. Since the reflectance at the end face changes, when the light beam is incident from the first optical waveguide member by appropriately setting the interval, the incident light beam is converted into the first optical waveguide member. When the light beam is incident from the second and third optical waveguide members after being split at a predetermined ratio at the inclined end surface of the optical system, the light beams are incident on the second and third optical waveguide members. The two light beams are combined at a predetermined ratio on the inclined end surface of the first optical waveguide member and enter the first optical waveguide member. Therefore, it is possible to provide an optical waveguide that can multiplex / demultiplex the light beam and that can route the optical wiring in the shape of h in the same plane with high coupling efficiency..
[0175]
According to the optical waveguide according to the invention of claim 8, in the optical waveguide of any one of claims 1, 4 and 6, the first optical waveguide member and the second optical waveguide member are respectively connected to each other. By making the refractive index of the propagating portion different from the refractive index of the medium around each inclined end surface, light incident at an angle of about 45 degrees with respect to the central axis of the inclined end surface is obtained at the center of the inclined end surface. Since the light beam can be totally reflected, the light beam can be totally reflected only by the inclined end surface, and the configuration of the inclined end surface becomes simple.
[0176]
According to the optical waveguide of the ninth aspect of the present invention, in the optical waveguide of any one of the first, fourth, and sixth aspects, the first optical waveguide member and the second optical waveguide member may be provided with respective inclined end surfaces. By arranging a metal layer on the inclined end face, it is possible to totally reflect light incident at an angle of about 45 degrees with respect to the central axis of the inclined end face at the center of the inclined end face. Since the incident light is reflected by the metal layer, even when the refractive index of the optical waveguide member does not satisfy the total reflection condition at the inclined end surface, the total reflection condition can be satisfied, and the Goose Henschen shift Need not be considered.
[0177]
According to the optical waveguide of the tenth aspect of the present invention, in the optical waveguide of any one of the first, fourth, and sixth aspects, the first optical waveguide member and the second optical waveguide member are arranged on each inclined end face. By disposing a plurality of dielectric layers having different refractive indexes of adjacent layers, light incident at an angle of approximately 45 degrees with respect to the central axis of the inclined end surface is provided at the center of the inclined end surface. Since it is possible to totally reflect, since the light incident on the inclined end face is reflected by the multilayer dielectric layer, even when the refractive index of the optical waveguide member does not satisfy the total reflection condition on the inclined end face, The total reflection condition can be satisfied.
[0178]
According to the optical waveguide of the invention of claim 11, in the optical waveguide of any of claims 1, 4 and 6, at least one of the first optical waveguide member and the second optical waveguide member is By disposing a multi-layered dielectric layer on the inclined end face, it is possible to totally reflect light incident at an angle of about 45 degrees with respect to the central axis of the inclined end face at the center of the inclined end face, and Since the multilayer dielectric layer selectively reflects the incident light selectively with respect to the wavelength, a light beam having a wavelength greater than or equal to a specific wavelength is incident on one of the optical waveguide members. Only when the incident light beam is transmitted to the other optical waveguide member, it can be used as a wavelength selective filter.
[0179]
According to the optical waveguide of the invention of claim 12, in the optical waveguide of claim 11, the first optical waveguide member and the second optical waveguide member are both provided with a multilayer dielectric layer. And the multilayer dielectric layers selectively reflect the incident light selectively with respect to different wavelengths, so that the wavelength selectivity of both multilayer dielectric layers is appropriately combined. Therefore, only when a light beam having a wavelength in a specific band is incident on one optical waveguide member, the incident light beam is transmitted or not transmitted to the other optical waveguide member. Therefore, it can be used as a band pass filter or a band rejection filter.
[0180]
According to the optical waveguide of the thirteenth aspect, in the optical waveguide according to any one of the first, second, fourth, fifth, sixth, seventh, and eighth aspects, the central axis is the inclined end face and the first optical waveguide is formed. Wave member / second optical waveguide member Each optical waveguide member intersecting the orthogonal axis of the wave member is Goose-Henschen shift with respect to light propagating along the central axis of the optical waveguide member along the inclined end surface. Since the virtual inclined end face having the apparent reflection point by the center is shifted so as to be located at the position where the inclined end face of each optical waveguide member exists in the optical waveguide of each claim, Goose Henschen The shift of the reflection point due to the shift is corrected, and accordingly, the coupling efficiency between the first and second optical waveguide members can be increased.
[0181]
According to the optical waveguide of the fourteenth aspect of the present invention, in the optical waveguide of the third aspect, the central axis intersects the first optical waveguide member / second optical waveguide member orthogonal axis at the inclined end surface. The optical waveguide member and each optical waveguide member whose central axis intersects with the third optical waveguide member / fourth optical waveguide member orthogonal axis at its inclined end face are parallel to the inclined end face of each optical waveguide member. And there is an inclined end face of each optical waveguide member in the optical waveguide according to claim 3, wherein the optical inclined end face has an apparent reflection point due to the Goose Henschen shift with respect to light propagating along the central axis. Since the positions are shifted so as to be positioned, the deviation of the reflection point due to the Goose Henschen shift is corrected, and accordingly, between the first and second optical waveguide members and the third and fourth optical waveguide members. The coupling efficiency between can be increased.
[0182]
According to the optical waveguide of the fifteenth aspect of the present invention, in any of the optical waveguides of the first to fourteenth aspects, each optical waveguide member is composed of a core and a clad, and is focused on the light beam by the side surfaces of each other. Since the interval between the members causing the effect is determined by a predetermined formula, the interval can be easily set.
[0183]
  According to the optical multiplexer / demultiplexer according to the invention of claim 15, claim 2Described inSince the interval between the inclined end surface of the first optical waveguide member and the inclined end surface of the third optical waveguide member of the optical waveguide can be changed, if the interval is changed, the first will be changed accordingly. The ratio of light multiplexing / demultiplexing at the inclined end face of the optical waveguide member changes. Therefore, it is possible to provide an optical multiplexer / demultiplexer that can perform multiplexing / demultiplexing with high efficiency and can change the ratio of the multiplexing / demultiplexing.
[0184]
  According to the optical multiplexer / demultiplexer according to the invention of claim 16, the optical multiplexer / demultiplexer of claim 16 is provided.Described inBetween the inclined end face of the first optical waveguide member and the inclined end face of the third optical waveguide member, a wavelength selective filter that selectively totally reflects light incident on the end face with respect to the wavelength. When the light beam composed of light having a wavelength smaller than the center wavelength of the wavelength selection filter and light having a wavelength larger than the center wavelength is incident on the first optical waveguide member, the incident light beam The light having one of the wavelengths is reflected or passed by the wavelength selection filter and output to the second optical waveguide member or the third optical waveguide member, and the light having the other wavelength is Then, the light is passed or reflected by the wavelength selection filter and output to the third optical waveguide member or the second optical waveguide member, and the incident light beam is wavelength-divided. For this reason, an optical multiplexer / demultiplexer capable of wavelength division can be provided.
[0185]
  According to the optical parallel bus of the seventeenth aspect,It is made of a material that can transmit light, has a cylindrical shape with a certain diameter, and its refractive index is different in the radial direction so that the light beam can propagate along the central axis. A center of the inclined end surface at the center of the inclined end surface due to the difference between the refractive index of the portion where the light beam propagates and the refractive index of the medium around the inclined end surface N (n: natural number of 2 or more) first optical waveguide members capable of totally reflecting light incident at an angle of about 45 degrees with respect to the axis, and the same structure as the first optical waveguide member And having n third optical waveguide members having inclined end surfaces inclined at approximately 45 degrees with respect to the central axis at one end thereof, and the n first optical waveguide members are connected to the first optical waveguide members. The central axes of the optical waveguide members are parallel to each other and are all located in the same plane, and the central axes of the first optical waveguide members The planes including the central axis of the inclined end faces are all perpendicular to the plane, and the inclined end faces of the first optical waveguide members are all directed in the same direction and viewed from the arrangement direction of the first optical waveguide members. The n optical waveguide members are arranged so as not to overlap with each other, and the n optical waveguide members correspond to the n optical waveguide members on a one-to-one basis so that the central axis of the optical waveguide members Coincides with the central axis of the corresponding first optical waveguide member, and the inclined end surface of the third optical waveguide member is substantially parallel to the inclined end surface of the corresponding first optical waveguide member at a predetermined interval. A first optical parallel bus that is arranged so as to have a cylindrical shape with a certain diameter and a radial direction so that the light beam can propagate along its central axis The refractive index is different, and an inclined end face inclined at about 45 degrees with respect to the central axis is formed at one end thereof. And n second optical waveguide members capable of totally reflecting light incident at an angle of about 45 degrees with respect to the central axis of the inclined end face at the center of the inclined end face, The second optical waveguide members correspond to the n first optical waveguide members on a one-to-one basis, and the center of the inclined end face of each second optical waveguide member is the first optical waveguide member. The first optical waveguide member / second optical waveguide member orthogonal to each of the first optical waveguide members substantially perpendicular to the central axis of each of the first optical waveguide members so as to sandwich the central axis of the inclined end surface at the center of the inclined end surface of each of the optical waveguide members. Each of the second optical waveguide members is located on the axis, the central axes of the respective second optical waveguide members are parallel to each other, are all located in the same plane, and the central axes of the inclined end faces of the respective second optical waveguide members are sandwiched therebetween. From the direction of the first optical waveguide member / second optical waveguide member orthogonal axis and substantially orthogonal to the first optical waveguide member / second optical waveguide member orthogonal axis As seen, the first optical waveguide member has a crossing angle of approximately 90 degrees with respect to the central axis of the first optical waveguide member, and the inclined end surface of the first optical waveguide member and the inclined end surface of the second optical waveguide member are The first optical waveguide member / the second optical waveguide member are oriented in opposite directions as viewed from the orthogonal axis direction, and the distance between each second optical waveguide member and each first optical waveguide member However, when a light beam is incident on one optical waveguide member, the light beam reflected at the center of the inclined end surface of the one optical waveguide member and having a diameter expanded by the reflection is caused by the side surfaces of both optical waveguide members. An interval at which the center of the inclined end face of the other optical waveguide member is positioned at a position having the same diameter as that of the light beam propagating through the other optical waveguide member due to the convergence effect. And a second optical parallel bus arranged so thatA first optical parallel bus formed by arranging a plurality of first optical waveguide members and third optical waveguide members in parallel and in a planar shape, and a second optical light corresponding to the first optical waveguide member on a one-to-one basis. The second optical parallel bus in which the wave members are arranged in parallel and in a planar shape means that each of the first optical waveguide members arranged so that the inclined end faces do not overlap when viewed from the arrangement direction. When viewed from the direction perpendicular to the arrangement surface of the first and second optical waveguide members, the two waveguide members intersect each other substantially at right angles so that both inclined end surfaces overlap each other, and each third optical waveguide member Are connected so as to be positioned on the extension of the first optical waveguide member with a predetermined interval, so that the waveguide members constituting each optical parallel bus can be arranged in close contact with each other. Space can be saved. In addition, since each first optical waveguide member and each second optical waveguide member form the optical waveguide according to claim 1, the coupling efficiency is substantially 1, and the efficiency is high.
[0186]
According to the optoelectronic integrated device of the nineteenth aspect, when the EO chip is mounted at a predetermined position on the EO board, the first optical waveguide member as the chip-side optical connecting means of the EO chip, and the EO chip Since the second optical waveguide member as the board-side optical connection means of the board forms the optical waveguide according to claim 1, the coupling efficiency is substantially 1, and the EO chip and the EO board are optically connected with high efficiency. Is done. In addition, the first optical waveguide member and the second optical waveguide member are optically connected when their distal ends are in contact with each other or at a predetermined interval, so that the EO chip and the EO board are connected to each other. It can be easily optically connected, and the configuration of the connecting portion is simple.
[Brief description of the drawings]
FIG. 1 is a diagram showing a configuration of an optical waveguide according to a first embodiment of the present invention, and is a perspective view (FIG. 1 (a)) and an arrow A view of FIG. 1 (a) (FIG. 1 (b)). And FIG. 1 (a) is an arrow B diagram (FIG. 1 (c)).
FIG. 2 is a schematic diagram showing an analysis model of an optical waveguide according to the first embodiment.
FIG. 3 is a graph showing the coupling efficiency η with respect to the parameter α of the optical waveguide according to the first embodiment.
FIG. 4 is a refractive index n of the clad of the optical waveguide according to the first embodiment._cIt is a graph which shows parameter (alpha) with respect to.
FIG. 5 is a graph showing a parameter α with respect to an optical fiber interval D expressed as a ratio to the cladding radius of the optical waveguide according to the first embodiment.
6 is a diagram showing a configuration of an optical waveguide according to a second embodiment of the present invention, and is a perspective view (FIG. 6 (a)) and an arrow A view in FIG. 6 (a) (FIG. 6 (b)). And FIG. 6 (a) shows an arrow B (FIG. 6 (c)).
7 is a diagram showing a configuration of an optical waveguide according to a third embodiment of the present invention, and is a perspective view (FIG. 7 (a)) and an arrow A view of FIG. 7 (a) (FIG. 7 (b)). And FIG. 7 (a) is an arrow B view (FIG. 7 (c)).
8 is a diagram showing a configuration of an optical waveguide according to a fourth embodiment of the present invention, and is a perspective view (FIG. 8 (a)), and an arrow A view in FIG. 8 (a) (FIG. 8 (b)). And FIG. 8 (a) is an arrow B view (FIG. 8 (c)).
FIG. 9 is a diagram showing a configuration of an optical waveguide according to a fifth embodiment of the present invention, and is a perspective view (FIG. 9 (a)) and an arrow A view of FIG. 9 (a) (FIG. 9 (b)). And FIG. 9 (a) shows an arrow B (FIG. 9 (c)).
FIG. 10 is a side view showing a structure of an inclined end face of an optical fiber in an optical waveguide according to a sixth embodiment of the present invention.
FIG. 11 is a side view showing a structure of an inclined end face of an optical fiber in an optical waveguide according to a seventh embodiment of the present invention.
FIG. 12 is a perspective view showing a configuration of an optical waveguide according to a ninth embodiment of the present invention.
13 is a view showing a configuration of an optical waveguide according to a tenth embodiment of the present invention, and is a perspective view (FIG. 13 (a)) and an arrow A view in FIG. 13 (a) (FIG. 13 (b)). And FIG. 13 (a) is an arrow B view (FIG. 13 (c)).
FIG. 14 is a diagram showing the configuration of an optical waveguide according to an eleventh embodiment of the present invention, and is a perspective view (FIG. 14 (a)) and an arrow A view in FIG. 14 (a) (FIG. 14 (b)). And FIG. 14 (a) is an arrow B view (FIG. 14 (c)).
15 is a view showing the structure of an optical waveguide according to a twelfth embodiment of the present invention, and is a perspective view (FIG. 15 (a)), and an arrow A view in FIG. 15 (a) (FIG. 15 (b)). And FIG. 15 (a) is an arrow B view (FIG. 15 (c)).
FIG. 16 is a view showing a configuration of an optical waveguide according to a thirteenth embodiment of the present invention, and is a perspective view (FIG. 16 (a)) and an arrow A view in FIG. 16 (a) (FIG. 16 (b)). And FIG. 16 (a) is an arrow B view (FIG. 16 (c)).
FIG. 17 is a diagram showing the position of an inclined end face of an optical fiber in an optical waveguide according to a fourteenth embodiment of the present invention.
18 is a diagram showing a configuration of an optical multiplexer / demultiplexer according to a fifteenth embodiment of the present invention, and is a front view (FIG. 18 (a)), and a diagram shown in FIG. 18A (FIG. 18 (a)). b)).
FIG. 19 is a front view showing a configuration of an optical multiplexer / demultiplexer according to a sixteenth embodiment of the present invention.
20 is a diagram showing a configuration of an optical parallel bus according to a seventeenth embodiment of the present invention, and is a top view (FIG. 20 (a)), and an arrow E diagram in FIG. 20 (a) (FIG. 20 (b)). )).
FIG. 21 is a perspective view showing a configuration of an optoelectronic integrated apparatus according to Embodiment 18 of the present invention.
FIG. 22 is a side view showing a conventional method of connecting optical fibers.
[Explanation of symbols]
1 core, 2 clad, 3 metal mirror, 4 multilayer mirror, 4a first multilayer mirror, 4b second multilayer mirror, 5 wavelength selection filter, 6 optical fiber fixing groove, 7 substrate, 10 optoelectronic integrated device, 11 EO chip, 12 E board layer, 13 O board layer, 14 EO board, 15 optical fiber insertion hole, 16 electrode pin, 17 electrode hole, 18 positioning convex part, 19 positioning concave part, 20 lever, 21 operation part, 22 pressing part, 23 rotation axis, 24 support member, 25-27 optical fiber, 100 rod lens, 101 half plate part, 102 semicircular part, Ax1 central axis of the first optical fiber, Ax2 center of the second optical fiber Axis, Ax3 first optical fiber / second optical fiber orthogonal axis, Ax4 central axis of the inclined end face of the first optical fiber, Ax5 second optical fiber The central axis of the inclined end face of the bar, the central axis of the Ax6 rod lens, the central axis of the Ax7 third optical fiber, the central axis of the Ax8 fourth optical fiber, the Ax9 third optical fiber / fourth optical fiber orthogonal axis, Ax10 central axis of the inclined end face of the third optical fiber, Ax11 central axis of the inclined end face of the fourth optical fiber, Bu optical parallel bus, Bu1 first optical parallel bus, Bu2 second optical parallel bus, Cp1 first Cp2 the center point of the inclined end face of the optical fiber, Cp2 the center point of the inclined end face of the second optical fiber, Cp3 the center point of the inclined end face of the third optical fiber, Cp4 the center point of the inclined end face of the fourth optical fiber, F1 Inclined end face of first optical fiber, F2 Inclined end face of second optical fiber, F3 Inclined end face of third optical fiber, F4 Inclined end face of fourth optical fiber, d Optical fiber spacing, n_c  The refractive index of the cladding, n_e  Equivalent refractive index, Of1 1st optical fiber, Of2 2nd optical fiber, Of3 3rd optical fiber, Of4 4th optical fiber, P1-P4 port, S The space | interval of inclined end surface F1 and inclined end surface F3.

Claims (18)

It is made of a material that can transmit light, and has a circular cross section and a shape extending in the direction of the central axis, and its refractive index in the radial direction of the cross section so that the light beam can propagate along the central axis. And having an inclined end face inclined at approximately 45 degrees with respect to the central axis at one end thereof, and light incident at an angle of approximately 45 degrees with respect to the central axis of the inclined end face at the central portion of the inclined end face. A first optical waveguide member capable of total reflection;
It is made of a material that can transmit light, and has a circular cross section and a shape extending in the direction of the central axis, and its refractive index in the radial direction of the cross section so that the light beam can propagate along the central axis. And having an inclined end face inclined at approximately 45 degrees with respect to the central axis at one end thereof, and light incident at an angle of approximately 45 degrees with respect to the central axis of the inclined end face at the central portion of the inclined end face. A second optical waveguide member capable of total reflection,
The first optical waveguide member and the second optical waveguide member are arranged such that the center of the inclined end surface of the second optical waveguide member is the center of the inclined end surface of the first optical waveguide member. Located on the first optical waveguide member / second optical waveguide member orthogonal axis that is substantially orthogonal to the central axis of the first optical waveguide member so as to sandwich the central axis,
The central axis of the second optical waveguide member is substantially orthogonal to the first optical waveguide member / second optical waveguide member orthogonal axis so as to sandwich the central axis of the inclined end surface of the second optical waveguide member, and The first optical waveguide member / the second optical waveguide member has a crossing angle of about 90 degrees with respect to the central axis of the first optical waveguide member when viewed from the direction perpendicular to the first optical waveguide member;
The inclined end face of the first optical waveguide member and the inclined end face of the second optical waveguide member face in opposite directions as viewed from the first optical waveguide member / second optical waveguide member orthogonal axis direction. ,
In addition, the distance between the first optical waveguide member and the second optical waveguide member is reflected at the center of the inclined end surface of the one optical waveguide member when the light beam is incident on the one optical waveguide member. And a position where the light beam whose diameter has been expanded by the reflection is subjected to a convergence effect by the side surfaces of both optical waveguide members and has a diameter substantially the same as the diameter when the light beam propagates through the other optical waveguide member And arranged such that the center of the inclined end face of the other optical waveguide member is located at an interval,
The optical waveguide member at the connecting portion between the first optical waveguide member and the second optical waveguide member has a certain diameter in the central axis direction and is arranged in a region extending from the center to a certain radius. A core having a refractive index and a clad having a refractive index smaller than the refractive index of the core disposed in a region extending from the core to the outer periphery;
The distance between the first optical waveguide member and the second optical waveguide member that produces a convergence effect on the light beam by the side surfaces of the first and second optical waveguide members,
The distance between the members is d, the equivalent refractive index of the core is ne, the refractive index of the clad is nc, the radius of the clad is a, the wavelength of the incident light beam is λ, and the light beam is incident on the member. When the spot size of the connection is ω,
α = (ne / nc) (1 + nc + nc D)
[(1 + nc D + nc −nc ² D) (nc −1) (1 + nc D)] ^−1/2 ,
Here, D = d / a as a parameter,
ω ² = λaα / π,
An optical waveguide characterized by being determined based on an expression represented by: The optical waveguide according to claim 1,
In the first optical waveguide member, the refractive index of the portion where light propagates is made different from the refractive index of the medium around the inclined end surface, so that the central portion of the inclined end surface is substantially the same as the central axis of the inclined end surface. It is possible to totally reflect light incident at an angle of 45 degrees,
In addition, it is made of a material that can transmit light, and has a circular cross section and a shape extending in the direction of the central axis, and in the radial direction of the cross section so that the light beam can propagate along the central axis. The third embodiment has different refractive indexes, has an inclined end face inclined at about 45 degrees with respect to the central axis at one end, and the structure of the inclined end face is the same as that of the inclined end face of the first optical waveguide member. Having an optical waveguide member of
With respect to the first optical waveguide member, the third optical waveguide member is arranged such that the central axis of the third optical waveguide member coincides with the central axis of the first optical waveguide member, and the third optical waveguide member optical waveguide inclined end face of the wave member, with respect to inclined end face of the first optical waveguide member, characterized by being arranged substantially in parallel at predetermined intervals. The optical waveguide according to claim 2, wherein
It is made of a material that can transmit light, and has a circular cross section and a shape extending in the direction of the central axis, and its refractive index in the radial direction of the cross section so that the light beam can propagate along the central axis. And having an inclined end face inclined at approximately 45 degrees with respect to the central axis at one end thereof, and light incident at an angle of approximately 45 degrees with respect to the central axis of the inclined end face at the central portion of the inclined end face. A fourth optical waveguide member capable of total reflection;
With respect to the third optical waveguide member, the fourth optical waveguide member is arranged such that the center of the inclined end surface of the fourth optical waveguide member is the center of the inclined end surface of the third optical waveguide member. Is located on the third optical waveguide member / fourth optical waveguide member orthogonal axis substantially orthogonal to the central axis of the third optical waveguide member so as to sandwich the central axis of
The central axis of the fourth optical waveguide member is substantially orthogonal to the third optical waveguide member / fourth optical waveguide member orthogonal axis so as to sandwich the central axis of the inclined end surface of the fourth optical waveguide member, and The third optical waveguide member / the fourth optical waveguide member have a crossing angle of about 90 degrees with respect to the central axis of the third optical waveguide member when viewed from the direction perpendicular to the third optical waveguide member,
The inclined end surface of the third optical waveguide member and the inclined end surface of the fourth optical waveguide member face in opposite directions as viewed from the third optical waveguide member / fourth optical waveguide member orthogonal axis direction. ,
In addition, the distance between the fourth optical waveguide member and the third optical waveguide member is reflected at the center of the inclined end surface of the one optical waveguide member when the light beam is incident on the one optical waveguide member. And a position where the light beam whose diameter has been expanded by the reflection is subjected to a convergence effect by the side surfaces of both optical waveguide members and has a diameter substantially the same as the diameter when the light beam propagates through the other optical waveguide member Are arranged such that the center of the inclined end face of the other optical waveguide member is located at an interval,
The optical waveguide member at the connecting portion between the third optical waveguide member and the fourth optical waveguide member has a certain diameter in the central axis direction and is disposed in a region extending from the center to a certain radius. A core having a refractive index and a clad having a refractive index smaller than the refractive index of the core disposed in a region extending from the core to the outer periphery;
The distance between the third optical waveguide member and the fourth optical waveguide member that produces a convergence effect on the light beam by the side surfaces of the third and fourth optical waveguide members,
The distance between the members is d, the equivalent refractive index of the core is ne, the refractive index of the clad is nc, the radius of the clad is a, the wavelength of the incident light beam is λ, and the light beam is incident on the member. When the spot size of the connection is ω,
α = (ne / nc) (1 + nc + nc D)
[(1 + nc D + nc −nc ² D) (nc −1) (1 + nc D)] ^−1/2 ,
Here, D = d / a as a parameter,
ω ² = λaα / π,
An optical waveguide characterized by being determined based on an expression represented by: It is made of a material that can transmit light, and has a circular cross section and a shape extending in the direction of the central axis, and its refractive index in the radial direction of the cross section so that the light beam can propagate along the central axis. And having an inclined end face inclined at approximately 45 degrees with respect to the central axis at one end thereof, and light incident at an angle of approximately 45 degrees with respect to the central axis of the inclined end face at the central portion of the inclined end face. A first optical waveguide member capable of total reflection;
It is made of a material that can transmit light, and has a circular cross section and a shape extending in the direction of the central axis, and its refractive index in the radial direction of the cross section so that the light beam can propagate along the central axis. And having an inclined end face inclined at approximately 45 degrees with respect to the central axis at one end thereof, and light incident at an angle of approximately 45 degrees with respect to the central axis of the inclined end face at the central portion of the inclined end face. A second optical waveguide member capable of total reflection;
A rod lens member made of a material capable of transmitting light and having a circular cross section and a shape extending in the central axis direction;
In the first optical waveguide member, the second optical waveguide member, and the rod lens member, the center of the inclined end surface of the second optical waveguide member is set to the center of the inclined end surface of the first optical waveguide member. And located on the first optical waveguide member / second optical waveguide member orthogonal axis substantially orthogonal to the central axis of the first optical waveguide member so as to sandwich the central axis of the inclined end surface,
The central axis of the second optical waveguide member is substantially orthogonal to the first optical waveguide member / second optical waveguide member orthogonal axis so as to sandwich the central axis of the inclined end surface of the second optical waveguide member, and The first optical waveguide member / the second optical waveguide member has a crossing angle of approximately 0 degrees with respect to the central axis of the first optical waveguide member as viewed from the direction perpendicular to the first optical waveguide member;
The first inclined end face of the first optical waveguide member and the second inclined end face of the second optical waveguide member are viewed from the first optical waveguide member / second optical waveguide member orthogonal axis direction. Facing opposite directions,
The central axis of the rod lens member is substantially perpendicular to the first optical waveguide member / second optical waveguide member orthogonal axis between the first optical waveguide member and the second optical waveguide member, and The first optical waveguide member / the second optical waveguide member are substantially perpendicular to the central axis of the first optical waveguide member and the central axis of the second optical waveguide member when viewed from the direction perpendicular to the first optical waveguide member / second optical waveguide member,
And when the distance between the first optical waveguide member and the rod lens member and the distance between the second optical waveguide member and the rod lens member are such that the light beam is incident on one of the optical waveguide members, A light beam reflected at the center of the inclined end surface of the one optical waveguide member and having a diameter expanded by the reflection is propagated through the other optical waveguide member by receiving a convergence effect by the side surfaces of both the optical waveguide member and the rod lens member. Arranged so that the center of the inclined end face of the other optical waveguide member is located at a position having substantially the same diameter as possible,
The optical waveguide member at the connecting portion between the first optical waveguide member and the second optical waveguide member has a certain diameter in the central axis direction and is arranged in a region extending from the center to a certain radius. A core having a refractive index and a clad having a refractive index smaller than the refractive index of the core disposed in a region extending from the core to the outer periphery;
The distance between the first optical waveguide member and the rod lens member and the second optical waveguide member and the rod that produce a converging effect on the light beam by the side surfaces of the first and second optical waveguide members and the rod lens member. The distance between the lens members
The distance between the members is d, the equivalent refractive index of the core is ne, the refractive index of the clad is nc, the radius of the clad is a, the wavelength of the incident light beam is λ, and the light beam is incident on the member. When the spot size of the connection is ω,
α = (ne / nc) (1 + nc + nc D)
[(1 + nc D + nc −nc ² D) (nc −1) (1 + nc D)] ^−1/2 ,
Here, D = d / a as a parameter,
ω ² = λaα / π,
An optical waveguide characterized by being determined based on an expression represented by: The optical waveguide according to claim 4, wherein
In the first optical waveguide member, the refractive index of the portion where light propagates is made different from the refractive index of the medium around the inclined end surface, so that the central portion of the inclined end surface is substantially the same as the central axis of the inclined end surface. It is possible to totally reflect light incident at an angle of 45 degrees,
In addition, it is made of a material that can transmit light, and has a circular cross section and a shape extending in the direction of the central axis, and in the radial direction of the cross section so that the light beam can propagate along the central axis. The third embodiment has different refractive indexes, has an inclined end face inclined at about 45 degrees with respect to the central axis at one end, and the structure of the inclined end face is the same as that of the inclined end face of the first optical waveguide member. Having an optical waveguide member of
With respect to the first optical waveguide member, the third optical waveguide member is arranged such that the central axis of the third optical waveguide member coincides with the central axis of the first optical waveguide member, and the third optical waveguide member optical waveguide inclined end face of the wave member, with respect to inclined end face of the first optical waveguide member, characterized by being arranged substantially in parallel at predetermined intervals. It is made of a material that can transmit light, and has a circular cross section and a shape extending in the direction of the central axis, and its refractive index in the radial direction of the cross section so that the light beam can propagate along the central axis. And having an inclined end face inclined at approximately 45 degrees with respect to the central axis at one end thereof, and light incident at an angle of approximately 45 degrees with respect to the central axis of the inclined end face at the central portion of the inclined end face. A first optical waveguide member capable of total reflection;
It is made of a material that can transmit light, and has a circular cross section and a shape extending in the direction of the central axis, and its refractive index in the radial direction of the cross section so that the light beam can propagate along the central axis. And having an inclined end face inclined at approximately 45 degrees with respect to the central axis at one end thereof, and light incident at an angle of approximately 45 degrees with respect to the central axis of the inclined end face at the central portion of the inclined end face. A second optical waveguide member capable of total reflection;
A rod lens member made of a material capable of transmitting light and having a circular cross section and a shape extending in the central axis direction;
In the first optical waveguide member, the second optical waveguide member, and the rod lens member, the center of the inclined end surface of the second optical waveguide member is set to the center of the inclined end surface of the first optical waveguide member. And located on the first optical waveguide member / second optical waveguide member orthogonal axis substantially orthogonal to the central axis of the first optical waveguide member so as to sandwich the central axis of the inclined end surface,
The central axis of the second optical waveguide member is substantially orthogonal to the first optical waveguide member / second optical waveguide member orthogonal axis so as to sandwich the central axis of the inclined end surface of the second optical waveguide member, and The first optical waveguide member / the second optical waveguide member have a crossing angle of about 180 degrees with respect to the central axis of the first optical waveguide member when viewed from the direction perpendicular to the first optical waveguide member,
The first inclined end face of the first optical waveguide member and the second inclined end face of the second optical waveguide member are viewed from the first optical waveguide member / second optical waveguide member orthogonal axis direction. Facing opposite directions,
The central axis of the rod lens member is substantially perpendicular to the first optical waveguide member / second optical waveguide member orthogonal axis between the first optical waveguide member and the second optical waveguide member, and The first optical waveguide member / the second optical waveguide member are substantially perpendicular to the central axis of the first optical waveguide member and the central axis of the second optical waveguide member when viewed from the direction perpendicular to the first optical waveguide member / second optical waveguide member,
And when the interval between the first optical waveguide member and the rod lens member and the interval between the second optical waveguide member and the rod lens member are such that a light beam is incident on one optical waveguide member, The light beam reflected at the center of the inclined end surface of the one optical waveguide member and having a diameter expanded by the reflection is subjected to the convergence effect by the side surfaces of both the optical waveguide member and the rod lens member, and the other optical waveguide member is Arranged so that the center of the inclined end face of the other optical waveguide member is positioned at a position that has substantially the same diameter as the diameter when the light beam propagates,
The optical waveguide member at the connecting portion between the first optical waveguide member and the second optical waveguide member has a certain diameter in the central axis direction and is arranged in a region extending from the center to a certain radius. A core having a refractive index and a clad having a refractive index smaller than the refractive index of the core disposed in a region extending from the core to the outer periphery;
The distance between the first optical waveguide member and the rod lens member and the second optical waveguide member and the rod that produce a converging effect on the light beam by the side surfaces of the first and second optical waveguide members and the rod lens member. The distance between the lens members
The distance between the members is d, the equivalent refractive index of the core is ne, the refractive index of the clad is nc, the radius of the clad is a, the wavelength of the incident light beam is λ, and the light beam is incident on the member. When the spot size of the connection is ω,
α = (ne / nc) (1 + nc + nc D)
[(1 + nc D + nc −nc ² D) (nc −1) (1 + nc D)] ^−1/2 ,
Here, D = d / a as a parameter,
ω ² = λaα / π,
An optical waveguide characterized by being determined based on an expression represented by: The optical waveguide according to claim 6, wherein
In the first optical waveguide member, the refractive index of the portion where light propagates is made different from the refractive index of the medium around the inclined end surface, so that the central portion of the inclined end surface is substantially the same as the central axis of the inclined end surface. It is possible to totally reflect light incident at an angle of 45 degrees,
In addition, it is made of a material that can transmit light, and has a circular cross section and a shape extending in the direction of the central axis, and in the radial direction of the cross section so that the light beam can propagate along the central axis. The third embodiment has different refractive indexes, has an inclined end face inclined at about 45 degrees with respect to the central axis at one end, and the structure of the inclined end face is the same as that of the inclined end face of the first optical waveguide member. Having an optical waveguide member of
With respect to the first optical waveguide member, the third optical waveguide member is arranged such that the central axis of the third optical waveguide member coincides with the central axis of the first optical waveguide member, and the third optical waveguide member optical waveguide inclined end face of the wave member, with respect to inclined end face of the first optical waveguide member, characterized by being arranged substantially in parallel at predetermined intervals. In the optical waveguide according to any one of claims 1, 4 and 6,
In the first optical waveguide member and the second optical waveguide member, the inclined end face is formed by making the refractive index of the portion where each light propagates different from the refractive index of the medium around each inclined end face. An optical waveguide characterized by being capable of totally reflecting light incident at an angle of about 45 degrees with respect to the central axis of the inclined end face at the center of the optical waveguide. In the optical waveguide according to any one of claims 1, 4 and 6,
In the first optical waveguide member and the second optical waveguide member, a metal layer is disposed on each inclined end surface, so that the central portion of the inclined end surface is approximately 45 degrees with respect to the central axis of the inclined end surface. An optical waveguide characterized by being capable of totally reflecting light incident at an angle of. In the optical waveguide according to any one of claims 1, 4 and 6,
Each of the first optical waveguide member and the second optical waveguide member is provided with a plurality of dielectric layers having different refractive indexes of adjacent layers on each inclined end face, thereby providing the inclined An optical waveguide characterized by being capable of totally reflecting light incident at an angle of about 45 degrees with respect to the central axis of the inclined end face at the center of the end face. In the optical waveguide according to any one of claims 1, 4 and 6,
At least one of the first optical waveguide member and the second optical waveguide member is formed by disposing a multilayer dielectric layer having different refractive indexes of adjacent layers on the inclined end surface. The light incident at an angle of about 45 degrees with respect to the central axis of the inclined end surface can be totally reflected at the central portion of the inclined end surface.
The multi-layer dielectric layer selectively reflects the incident light selectively with respect to the wavelength. The optical waveguide according to claim 11, wherein
The first optical waveguide member and the second optical waveguide member are both provided with the multilayer dielectric layers, and the multilayer dielectric layers are selected for different wavelengths. An optical waveguide characterized by totally reflecting the incident light. In the optical waveguide according to any one of claims 1, 2, 4, 5, 6, 7, and 8,
Each optical waveguide member whose central axis intersects the first optical waveguide member / second optical waveguide member orthogonal axis at its inclined end face is parallel to the inclined end face of each optical waveguide member and its A virtual inclined end face having an apparent reflection point due to Goose-Henschen shift with respect to light propagating along the central axis is located at a position where the inclined end face of each optical waveguide member exists in the optical waveguide according to any of the above claims. The optical waveguide is characterized by being arranged so as to be shifted. The optical waveguide according to claim 3,
Each optical waveguide member whose central axis intersects the first optical waveguide member / second optical waveguide member orthogonal axis at its inclined end surface, and its third optical waveguide member / second optical axis whose central axis is its inclined end surface. Each optical waveguide member intersecting the optical waveguide member orthogonal axis of 4 is apparently due to the Goose Henschen shift for light propagating along the central axis of the optical waveguide member along the inclined end surface. An optical waveguide characterized in that an imaginary inclined end face having a reflection point as a center is shifted so that the inclined end face of each optical waveguide member exists in the optical waveguide of claim 3. The distance between the inclined end face of the first optical waveguide member and the inclined end face of the third optical waveguide member of the optical waveguide according to claim 2 is set such that the central axis of the third optical waveguide member is the first optical waveguide. The inclined end face of the third optical waveguide member coincides with the central axis of the member, and can be changed so as to be kept substantially parallel to the inclined end face of the first optical waveguide member. An optical multiplexer / demultiplexer characterized by that. The light incident on the end face of the optical waveguide according to claim 2 is selectively totally reflected with respect to the wavelength between the inclined end face of the first optical waveguide member and the inclined end face of the third optical waveguide member. An optical multiplexer / demultiplexer characterized by interposing a wavelength selection filter. It is made of a material that can transmit light, has a cylindrical shape with a certain diameter, and its refractive index is different in the radial direction so that the light beam can propagate along the central axis. A center of the inclined end surface at the center of the inclined end surface due to the difference between the refractive index of the portion where the light beam propagates and the refractive index of the medium around the inclined end surface N (n: natural number of 2 or more) first optical waveguide members capable of totally reflecting light incident at an angle of about 45 degrees with respect to the axis, and the same structure as the first optical waveguide member And having n third optical waveguide members having inclined end faces inclined at approximately 45 degrees with respect to the central axis at one end thereof,
A first optical waveguide member of the n pieces of respective first optical waveguide member all central axes parallel to each other and located in the same plane, the respective central axis and the inclined end faces of the first optical waveguide member plane all becomes perpendicular to the plane including the central axis, and each of said first optical waveguide member overlap with al all inclined end faces to each other as viewed in the same direction orientation and the arrangement direction of the first optical waveguide member So that the n third optical waveguide members correspond to the n first optical waveguide members on a one-to-one basis, and the central axis of the third optical waveguide member is , Coincident with the central axis of the corresponding first optical waveguide member, and the inclined end surface of the third optical waveguide member is substantially parallel to the inclined end surface of the corresponding first optical waveguide member at a predetermined interval. A first optical parallel bus arranged so that
It is made of a material that can transmit light, has a cylindrical shape with a certain diameter, and its refractive index is different in the radial direction so that the light beam can propagate along the central axis. N second end surfaces having an inclined end surface inclined at approximately 45 degrees and capable of totally reflecting light incident at an angle of approximately 45 degrees with respect to the central axis of the inclined end surface at the center of the inclined end surface. Having an optical waveguide member,
The n second optical waveguide members correspond to the n first optical waveguide members on a one-to-one basis, and the centers of the inclined end faces of the second optical waveguide members are Each first optical waveguide member / second optical waveguide that is substantially orthogonal to the central axis of each first optical waveguide member so as to sandwich the central axis of the inclined end surface at the center of the inclined end surface of the first optical waveguide member. Located on the member orthogonal axis,
The first optical waveguide members are arranged such that the central axes of the second optical waveguide members are parallel to each other and are located in the same plane and sandwich the central axis of the inclined end surface of the second optical waveguide member. / 90 substantially perpendicular to the second optical waveguide member orthogonal axis and approximately 90 with respect to the central axis of each first optical waveguide member when viewed from the direction of the first optical waveguide member / second optical waveguide member orthogonal axis. Have a crossing angle of degrees,
The inclined end surface of each of the first optical waveguide members and the inclined end surface of each of the second optical waveguide members are opposite to each other when viewed from the first optical waveguide member / second optical waveguide member orthogonal axis direction. Facing direction,
The distance between each second optical waveguide member and each first optical waveguide member is reflected at the center of the inclined end surface of the one optical waveguide member when a light beam is incident on the one optical waveguide member. In addition, the light beam whose diameter is expanded by the reflection is subjected to the convergence effect by the side surfaces of both optical waveguide members, and has a diameter substantially equal to the diameter when the light beam propagates through the other optical waveguide member. An optical parallel bus comprising: a second optical parallel bus disposed at a position such that the center of the inclined end face of the other optical waveguide member is positioned at a position. Integrated electronic element and optical element, chip-side contact electrode electrically connected to an optoelectronic circuit including the electronic element and the optical element and arranged to be accessible from the outside, and photoelectron including the electronic element and the optical element An EO chip having chip-side optical connection means for optically connecting a circuit to the outside;
The EO chip can be detachably mounted at a predetermined position, and board-side contact that comes into contact with the electrical wiring and the contact electrode of the EO chip when the EO chip is mounted connected to the electrical wiring. An EO board having board-side optical connection means for connecting the chip-side optical connection means of the EO chip to the optical wiring when the EO chip is mounted,
The chip-side optical connecting means of the EO chip is made of a light-transmitting material protruding from the EO chip so as to be accessible from the outside, and has a circular cross section and a shape extending in the central axis direction. The refractive index is varied in the radial direction of the cross section so that the light beam can propagate along the central axis, and the base end of the EO chip includes the electronic device and the optoelectronic circuit including the optical device and the optical circuit. And has an inclined end face inclined at approximately 45 degrees with respect to the central axis at the tip thereof, and all light incident at an angle of approximately 45 degrees with respect to the central axis of the inclined end face is formed at the center of the inclined end face. It is composed of n (n: a natural number of 1 or more) first optical waveguide members that can be reflected,
The board-side optical connecting means of the EO board is made of a material that can transmit light, has a circular cross section and has a shape extending in the direction of the central axis, so that the light beam can propagate along the central axis. And having a refractive index different from each other in the radial direction of the cross section, its base end being connected to the optical wiring of the EO board, and having an inclined end face inclined at about 45 degrees with respect to its central axis at its tip, N second optical waveguide members capable of totally reflecting light incident at an angle of about 45 degrees with respect to the central axis of the inclined end surface at the center of the inclined end surface;
1-to-1 correspondence with the n first optical waveguide members of the EO chip,
When the EO chip is mounted, the center of the inclined end surface of each second optical waveguide member is sandwiched between the center of the inclined end surface of each first optical waveguide member and the center axis of the inclined end surface. Located on each first optical waveguide member / second optical waveguide member orthogonal axis substantially orthogonal to the central axis of the first optical waveguide member,
The central axis of each second optical waveguide member is substantially orthogonal to the first optical waveguide member / second optical waveguide member orthogonal axis so as to sandwich the central axis of the inclined end face of each second optical waveguide member. And having a crossing angle of approximately 90 degrees with respect to the central axis of each first optical waveguide member when viewed from the direction perpendicular to each first optical waveguide member / second optical waveguide member.
The inclined end surface of each of the first optical waveguide members and the inclined end surface of each of the second optical waveguide members are opposite to each other when viewed from the first optical waveguide member / second optical waveguide member orthogonal axis direction. Facing direction,
In addition, when the light beam is incident on one of the optical waveguide members, the distance between the second optical waveguide member and the first optical waveguide member is the center of the inclined end surface of the one optical waveguide member. The light beam reflected and expanded in diameter by the reflection is subjected to the convergence effect by the side surfaces of both optical waveguide members, and has a diameter substantially the same as the diameter when the light beam propagates through the other optical waveguide member. An optoelectronic integrated device characterized in that the EO board protrudes from the EO board at such a distance that the center of the inclined end face of the other optical waveguide member is located.

Images