JPH01183622A - Optical fiber type polarized light beam splitter - Google Patents

Optical fiber type polarized light beam splitter

Info

Publication number
JPH01183622A
JPH01183622A JP687888A JP687888A JPH01183622A JP H01183622 A JPH01183622 A JP H01183622A JP 687888 A JP687888 A JP 687888A JP 687888 A JP687888 A JP 687888A JP H01183622 A JPH01183622 A JP H01183622A
Authority
JP
Japan
Prior art keywords
optical fiber
port
beam splitter
axis
polarizer
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP687888A
Other languages
Japanese (ja)
Inventor
Takeyoshi Takuma
詫摩 勇悦
Toshihiko Ishikawa
俊彦 石川
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hitachi Cable Ltd
Original Assignee
Hitachi Cable Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hitachi Cable Ltd filed Critical Hitachi Cable Ltd
Priority to JP687888A priority Critical patent/JPH01183622A/en
Publication of JPH01183622A publication Critical patent/JPH01183622A/en
Pending legal-status Critical Current

Links

Landscapes

  • Polarising Elements (AREA)

Abstract

PURPOSE:To attenuate an unnecessary polarized wave and to obtain a splitter of a high quenching ratio by constituting the splitter so that in two emitting ports of a coupler, as for one of them, a slow axis is allowed to coincide with a transmission axis of an optical fiber type polarizer, and the other is allowed to be orthogonal to the transmission axis. CONSTITUTION:When a light beam which is polarized in the long axis direction of an elliptical jacket 12 is made incident on an incident port 4 of a direction coupler 1, since the polarized wave of an output port 6 of transmission side coincides with a transmission axis of a polarizer 2, it passes it through at a low loss, and emitted from an emitting port end 8. On the other hand, a polarized wave of an emitting port 7 of a coupling side coincides with a jacket short axis and goes to orthogonal to the transmission axis, therefore, attenuated and not emitted from an emitting end 9. In the same way, when a light beam which is polarized in the short axis direction of the jacket 12 is made incident on the port 4, it is not emitted from the output end 8 but emitted from the output end 9 without being attenuated. In such a way, an unnecessary polarized wave from the emitting port is attenuated and a polarization beam splitter of a high quenching ratio is obtained.

Description

【発明の詳細な説明】 [産業上の利用分野] 本発明は偏波面保存光ファイバを用いた光ファイバ形偏
光ビームスプリッタに関する。
DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an optical fiber type polarizing beam splitter using a polarization maintaining optical fiber.

[従来の技術] 入射光を直交する二つの偏光成分に分離する偏光ビーム
スプリッタは、従来はとんどがバルク形のものである。
[Prior Art] Conventionally, most polarizing beam splitters that separate incident light into two orthogonal polarization components are of the bulk type.

ファイバ形としては第6図に示すようにパンダ形偏波面
保存光ファイバ21を用いた偏光ビームスプリッタ(横
浜、他[ファイバ形偏光ビームスプリッタJ 0QE8
5−15PP、19−24゜1985)がある。これは
、二本の偏波面保存光ファイバ21を融着し延伸した融
着延伸型であり、光結合部(テーバ領域部)22の長さ
を調整して偏波分離を行うようにしたものである。この
テーバ領域部22の長さは偏波面保存光ファイバ21の
モード複屈折率Bに依存し、Bが大きい程テーバ領域部
22の長さは短い。
As for the fiber type, as shown in Fig. 6, there is a polarizing beam splitter (Yokohama, et al. [Fiber type polarizing beam splitter J 0QE8
5-15PP, 19-24°1985). This is a fusion-stretched type in which two polarization-maintaining optical fibers 21 are fused and stretched, and the length of the optical coupling part (Taber region part) 22 is adjusted to perform polarization separation. It is. The length of this Taber region portion 22 depends on the mode birefringence B of the polarization maintaining optical fiber 21, and the larger B is, the shorter the length of the Taber region portion 22 is.

[発明が解決しようとする課題] バルク形の偏光ビームスプリッタは光ファイバとの結合
に問題がある。すなわち−口先ビームをレンズ等により
空間に拡げなければいけないため、系全体をコンパクト
化し難い。また、2つの直角プリズムの間に誘電体多層
膜を入れて光学ボンド等で張り合わせているため、高温
及び低温で張り合せがとれるという信頼性の問題もある
[Problems to be Solved by the Invention] Bulk type polarizing beam splitters have problems in coupling with optical fibers. In other words, it is difficult to make the entire system compact because the snout beam must be spread in space using a lens or the like. Furthermore, since a dielectric multilayer film is inserted between two right-angled prisms and bonded together with an optical bond, there is a reliability problem in that the bonding can be removed at high and low temperatures.

パンダ形偏波面保存光ファイバ21を使った融着延伸型
の偏光ビームスプリッタは、通常の分岐比50%の3d
Bカツプラとは異なり、モード複屈折率Bに依存してテ
ーバ領域部22の長さを決定する必要がある。このため
、通常の3dBカツプラが使えず、量産性に難点がある
などの問題がある。
A fusion-stretched polarizing beam splitter using a panda-shaped polarization-maintaining optical fiber 21 is a 3D beam splitter with a normal branching ratio of 50%.
Unlike the B coupler, it is necessary to determine the length of the Taber region 22 depending on the mode birefringence B. For this reason, there are problems such as the fact that a normal 3 dB coupler cannot be used and there are difficulties in mass production.

本発明の目的は、信頼性及び出産性のある光ファイバ形
偏光ビームスプリッタを提供することにある。
SUMMARY OF THE INVENTION An object of the present invention is to provide a reliable and durable optical fiber polarizing beam splitter.

[81題を解決するための手段] 本発明の光ファイバ形偏光ビームスプリッタは、偏波面
保存光ファイバを用いた研磨型方向性結合器の2つの出
射ポートのうち、一方の出射ポートはそのスロー軸を偏
波面保存光ファイバを用いた光ファイバ形偏光子の透過
軸と一致させて接続し、他方の出射ポートはそのスロー
軸を光ファイバ形偏光子の透過軸と直交させて接続した
ものである。
[Means for Solving Problem 81] In the optical fiber type polarizing beam splitter of the present invention, one of the two output ports of a polishing type directional coupler using a polarization maintaining optical fiber is The output port is connected with its axis aligned with the transmission axis of an optical fiber polarizer using a polarization maintaining optical fiber, and the other output port is connected with its slow axis perpendicular to the transmission axis of the optical fiber polarizer. be.

[作 用] 研磨型方向性結合器のいずれか一方の入射ポートから入
射された光はその入射ポートの透過側及び結合側の2つ
の出射ポートに分岐されるが、−方の出射ポートのスロ
ー軸は光ファイバ形偏光子の透過軸に一致させ、他方の
出射ポートのスロー軸は光ファイバ形偏光子の透過軸に
直交させているので、各出射ポートからの不要な偏波は
光ファイバ形偏光子で減衰され、高消光比の偏光ビーム
スプリッタとなる。
[Function] Light incident from one of the input ports of a polishing type directional coupler is split into two output ports, one on the transmission side and one on the coupling side of that input port. The axis is aligned with the transmission axis of the optical fiber type polarizer, and the slow axis of the other output port is perpendicular to the transmission axis of the optical fiber type polarizer, so unnecessary polarized waves from each output port are transmitted through the optical fiber type polarizer. It is attenuated by a polarizer and becomes a polarizing beam splitter with a high extinction ratio.

[実施例] 以下に本発明の実施例を図面を用いて説明する。[Example] Embodiments of the present invention will be described below with reference to the drawings.

第1図に楕円ジャケット型偏波面保存光ファイバを用い
た偏光ビームスプリッタの構成を示す。
FIG. 1 shows the configuration of a polarizing beam splitter using an elliptical jacket type polarization maintaining optical fiber.

光ファイバ形偏光ビームスプリッタは、研磨型方向性結
合器1とその2つの出射ポート6.7にそれぞれ接続さ
れる光ファイバ形偏光子2.2とからなる。3は融着等
による接続部である。
The optical fiber type polarizing beam splitter consists of a polishing type directional coupler 1 and optical fiber type polarizers 2.2 connected to its two output ports 6.7, respectively. Reference numeral 3 indicates a connection portion by fusion bonding or the like.

研磨型方向性結合器1は、第1図ないし第2図に示すよ
うに、石英基板10に形成した湾曲した溝内に楕円ジャ
ケット型の偏波面保存光ファイバ11をその楕円ジャケ
ット12の長袖方向が石英基板10の面に垂直となるよ
うにして挿入して固定した後、コア13近傍まで石英基
板10を研磨し、このようにして作製した2枚の石英基
板10の研磨面を接合したものである。4.5は研磨型
方向性結合器1の入射ポート、6.7は出射ポートであ
って、分岐比を50%とした通常の3dBカツプうであ
る。なお、偏波面保存光ファイバ11はコア13、クラ
ッド、楕円ジャケット12及びサポート14の4層構造
を有するが、クラッドは図面の簡単化のために楕円ジャ
ケット12に含ませて省略した。偏波面保存光ファイバ
には楕円ジャケット型だけでなく、楕円クラッド型のも
のなども含まれる。
As shown in FIGS. 1 and 2, the polishing type directional coupler 1 includes an elliptical jacket type polarization maintaining optical fiber 11 placed in a curved groove formed in a quartz substrate 10 in the long sleeve direction of the elliptical jacket 12. After inserting and fixing the quartz substrate 10 so that it is perpendicular to the surface of the quartz substrate 10, the quartz substrate 10 is polished to the vicinity of the core 13, and the polished surfaces of the two quartz substrates 10 thus prepared are joined. It is. 4.5 is an input port of the polishing type directional coupler 1, and 6.7 is an output port, which is a normal 3 dB cup with a branching ratio of 50%. The polarization maintaining optical fiber 11 has a four-layer structure including a core 13, a cladding, an elliptical jacket 12, and a support 14, but the cladding is included in the elliptical jacket 12 and omitted to simplify the drawing. Polarization maintaining optical fibers include not only elliptical jacket type fibers but also elliptical clad type fibers.

光フアイバ偏光子2は偏波面保存光ファイバ11(ある
いは絶対単一偏波面保存光ファイバ)を巻回して絶対単
一動作としたものであり、楕円ジャケット12の長軸方
向(透過軸方向)に偏波した光のみ透過する。
The optical fiber polarizer 2 is made by winding a polarization-maintaining optical fiber 11 (or an absolutely single polarization-maintaining optical fiber) so that it operates in an absolutely single motion. Only polarized light is transmitted.

出射ポート6では、第3図に示すように出射ポート6の
偏波面保存光ファイバ11の楕円ジャケット12の長軸
(スロー軸)を光ファイバ形偏光子2の楕円ジャケット
12の長軸(透過軸)と−致させて接続する。一方、出
射ポート7では楕円ジャケット12の長@(スロー軸)
を光ファイバ形偏光子2の楕円ジャケラi〜12の長軸
(透過軸)と直交させて接続する。
At the output port 6, as shown in FIG. ) and connect. On the other hand, at the exit port 7, the length of the elliptical jacket 12 @ (slow axis)
are connected perpendicularly to the long axes (transmission axes) of the elliptical jackets i to 12 of the optical fiber polarizer 2.

第3図に示すように、方向性結合器1の入射ポート4に
楕円ジトケット1プの長軸方向に偏波した光(X偏波)
が入射すると、出射ポート6.7にはそれぞれX偏波が
等分されて来る。入射ポート4の透過側の出射ポート6
に来たX偏波は偏光子2の透過軸と一致しているため、
低損失で偏光子2を通過して出射ポート端8より出射す
る。−方、入射ポート4の結合側の出射ポート7に来た
X偏波は偏光子2の楕円ジjtケット短軸に一致し透過
軸(楕円ジャケット長軸)とは直交しているため、偏光
子2内で減衰され出射端9からは出射されない。
As shown in FIG. 3, light (X polarization) polarized in the long axis direction of the elliptical jitocket 1 enters the input port 4 of the directional coupler 1.
When the beam is incident, the X-polarized waves are equally divided into the output ports 6 and 7, respectively. Output port 6 on the transmission side of input port 4
Since the X-polarized wave that came to coincides with the transmission axis of polarizer 2,
The light passes through the polarizer 2 with low loss and is emitted from the output port end 8. On the other hand, the X-polarized wave arriving at the output port 7 on the coupling side of the input port 4 coincides with the short axis of the elliptical jacket of the polarizer 2 and is perpendicular to the transmission axis (long axis of the elliptical jacket), so the polarized light The light is attenuated within the child 2 and is not emitted from the output end 9.

同様にして、第4図に示すように、入射ポート4に楕円
ジャケット12の短軸方向に偏波した光(Y偏波)が入
射すると、出射ポート6のY偏波は偏光子で減衰されて
出射端8からは出射しないが、出射ポート7のY偏波は
偏光子2でほとんど減衰されることなく出射端9から出
射する。
Similarly, as shown in FIG. 4, when light polarized in the short axis direction of the elliptical jacket 12 (Y polarization) enters the input port 4, the Y polarization at the output port 6 is attenuated by the polarizer. However, the Y polarized wave from the output port 7 is hardly attenuated by the polarizer 2 and is output from the output end 9.

また、第5図に示すように、入射ポート4に楕円ジャケ
ット12の長袖と45″をなして直線偏波が入射すると
、出射ポート6.7では楕円偏光(方向性結合器1の偏
波面保存光ファイバ11のファイバ長によっては円偏光
あるいは直線偏光)となるが、光ファイバ形偏光子2,
2の透過軸にしたがって出射端8からはxN波が、また
出射端9からはY偏波が出射する。
Furthermore, as shown in FIG. Depending on the fiber length of the optical fiber 11, the light is circularly polarized or linearly polarized, but the optical fiber polarizer 2,
According to the transmission axis 2, xN waves are emitted from the output end 8, and Y-polarized waves are emitted from the output end 9.

実際に楕円ジャケット型偏波面保存光ファイバで上記の
偏光ビームスプリッタを試作した。研磨型方向性結合器
1は消光比−20dB (全ポート)、過剰損失0.2
dBであり、光ファイバ形偏光了2は消光比−47dB
、挿入損失0.3dBという特性である。
We actually fabricated a prototype polarizing beam splitter using an elliptical jacket type polarization-maintaining optical fiber. Polished directional coupler 1 has an extinction ratio of -20 dB (all ports) and an excess loss of 0.2.
dB, and the optical fiber type polarized light has an extinction ratio of -47 dB.
, the insertion loss is 0.3 dB.

得られた偏光ビームスプリッタの特性は、挿入損失がX
偏波、Y偏波ともに3.5dB、消光比が一41dB、
分離比が1=1(入射ポート4に45°直線偏波入射時
の出射端8.9の光出力比)であった。
The characteristics of the obtained polarizing beam splitter are that the insertion loss is
Both polarization and Y polarization are 3.5 dB, extinction ratio is 141 dB,
The separation ratio was 1=1 (light output ratio at the output end 8.9 when a 45° linearly polarized wave was incident on the input port 4).

[発明の効果コ 本発明によれば次のような優れた効果を発揮する。[Effects of invention According to the present invention, the following excellent effects are exhibited.

(1)  偏波面保存光ファイバを用いた光ファイバ形
方向性結合器であるため、光ファイバとの結合が容易で
あり且つ信頼性の高い偏光ビームスプリッタが得られる
(1) Since it is an optical fiber type directional coupler using a polarization maintaining optical fiber, it is easy to couple with the optical fiber and a highly reliable polarizing beam splitter can be obtained.

(2)  通常の3dBの研磨型り向性結合器を使用す
ることができるため、量産に適しコスi−ダウンが図れ
る。
(2) Since a normal 3 dB polished directional coupler can be used, it is suitable for mass production and can reduce cost.

(3)  光ファイバ形偏光子により不要な偏波を減衰
させているため、高消光比の偏光ビームスプリッタが得
られる。このため、本偏光ビームスプリッタを用いたシ
ステムの機能を向上させることがIII侍できる。
(3) Since unnecessary polarized waves are attenuated by the optical fiber polarizer, a polarizing beam splitter with a high extinction ratio can be obtained. Therefore, it is possible to improve the functionality of a system using this polarizing beam splitter.

【図面の簡単な説明】[Brief explanation of the drawing]

第1図は本発明の光ファイバ形偏光ビームスプリッタの
一実施例を示す構成図、第2図は同偏光ビームスプリッ
タに用いた研磨型方向性結合器の拡大した横断面図、第
3図、第4図、第5図は第1図の研磨型方向性結合器の
入射ポートにその楕円ジャケットの長軸に対して0°。 90°、45”の直線偏波をそれぞれ入射したときの様
子を示す説明図、第6図は従来の光ファイバ形偏光ビー
ムスプリッタの斜視図である。 図中、1は研磨型方向性結合器、2は光ファイバ形偏光
子、3は接続部、4.5は入射ポート、6.7は出射ポ
ート、8,9は出射端、10は石英基板、11は偏波面
保存光ファイバ、12は楕円ジャケット、13はコア、
14はサポート、21は偏波面保存光ファイバ、22は
テーパ領域部である。
FIG. 1 is a configuration diagram showing an embodiment of the optical fiber type polarizing beam splitter of the present invention, FIG. 2 is an enlarged cross-sectional view of a polishing type directional coupler used in the polarizing beam splitter, and FIG. 4 and 5 show the input port of the polished directional coupler of FIG. 1 at 0° with respect to the long axis of the elliptical jacket. Fig. 6 is a perspective view of a conventional optical fiber type polarizing beam splitter. In the figure, 1 is a polishing type directional coupler. , 2 is an optical fiber type polarizer, 3 is a connection part, 4.5 is an input port, 6.7 is an output port, 8 and 9 are output ends, 10 is a quartz substrate, 11 is a polarization-maintaining optical fiber, and 12 is a polarization-maintaining optical fiber. Oval jacket, 13 is core,
14 is a support, 21 is a polarization maintaining optical fiber, and 22 is a tapered region.

Claims (1)

【特許請求の範囲】[Claims] 1、偏波面保存光ファイバを用いた研磨型方向性結合器
の2つの出射ポートのうち、一方の出射ポートはそのス
ロー軸を偏波面保存光ファイバを用いた光ファイバ形偏
光子の透過軸と一致させて接続し、他方の出射ポートは
そのスロー軸を光ファイバ形偏光子の透過軸と直交させ
て接続したことを特徴とする光ファイバ形偏光ビームス
プリッタ。
1. Of the two output ports of a polished directional coupler using a polarization-maintaining optical fiber, one output port has its slow axis aligned with the transmission axis of the optical fiber polarizer using a polarization-maintaining optical fiber. 1. An optical fiber type polarizing beam splitter, characterized in that the other output port is connected with its slow axis orthogonal to the transmission axis of the optical fiber type polarizer.
JP687888A 1988-01-18 1988-01-18 Optical fiber type polarized light beam splitter Pending JPH01183622A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP687888A JPH01183622A (en) 1988-01-18 1988-01-18 Optical fiber type polarized light beam splitter

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP687888A JPH01183622A (en) 1988-01-18 1988-01-18 Optical fiber type polarized light beam splitter

Publications (1)

Publication Number Publication Date
JPH01183622A true JPH01183622A (en) 1989-07-21

Family

ID=11650480

Family Applications (1)

Application Number Title Priority Date Filing Date
JP687888A Pending JPH01183622A (en) 1988-01-18 1988-01-18 Optical fiber type polarized light beam splitter

Country Status (1)

Country Link
JP (1) JPH01183622A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109655231A (en) * 2018-11-20 2019-04-19 湖北三江航天红峰控制有限公司 2 × 2 polarization-maintaining optical fiber beam splitter working shaft detection methods of one kind and system

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109655231A (en) * 2018-11-20 2019-04-19 湖北三江航天红峰控制有限公司 2 × 2 polarization-maintaining optical fiber beam splitter working shaft detection methods of one kind and system
CN109655231B (en) * 2018-11-20 2020-07-14 湖北三江航天红峰控制有限公司 Method and system for detecting working axis of 2 × 2 polarization maintaining optical fiber beam splitter

Similar Documents

Publication Publication Date Title
US5446813A (en) Optical isolator
JPH03100604A (en) Fused optical fiber and method of manufacturing the same
JPH01183622A (en) Optical fiber type polarized light beam splitter
EP0874263A1 (en) Optical circulator
JPH1138363A (en) 3 port type optical circulator
JPH0566362A (en) Polarization independent type optical isolator
JP2925253B2 (en) Optical fiber coupler and manufacturing method thereof
JP2514491B2 (en) Fiber optic gyro
JP2879268B2 (en) Optical branch coupler storage structure
WO2020259239A1 (en) Miniaturized three-port optical circulator with standard optical interface
JP4156159B2 (en) Polarization maintaining optical signal delay circuit
JPS5981618A (en) Optical coupler
JP4888780B2 (en) Optical fiber coupler
JP2537473Y2 (en) Optical multiplexing circuit
JP2585272Y2 (en) Fiber type optical isolator
JP2611812B2 (en) Optical splitter / combiner
JPH05241104A (en) Polarized light rotating mirror
JPH02281211A (en) Optical collimator and optical coupling parts
JP3481699B2 (en) Optical isolator
JPH041718A (en) Optical collimator and optical coupling parts
JPH07318744A (en) Optical composite parts for optical fiber amplifier
JPH08184727A (en) Optical connector
JPH04335304A (en) Polarized light coupler with microlens optical fiber terminal
JP2611814B2 (en) Optical splitter / combiner
JP2003232955A (en) Optical fiber type polarizer