JPS58116784A - Semiconductor laser module - Google Patents

Semiconductor laser module

Info

Publication number
JPS58116784A
JPS58116784A JP21065081A JP21065081A JPS58116784A JP S58116784 A JPS58116784 A JP S58116784A JP 21065081 A JP21065081 A JP 21065081A JP 21065081 A JP21065081 A JP 21065081A JP S58116784 A JPS58116784 A JP S58116784A
Authority
JP
Japan
Prior art keywords
optical fiber
waveguide
semiconductor laser
terminal
electrodes
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP21065081A
Other languages
Japanese (ja)
Other versions
JPS6410958B2 (en
Inventor
Masao Makiuchi
正男 牧内
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.)
Fujitsu Ltd
Original Assignee
Fujitsu 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 Fujitsu Ltd filed Critical Fujitsu Ltd
Priority to JP21065081A priority Critical patent/JPS58116784A/en
Publication of JPS58116784A publication Critical patent/JPS58116784A/en
Publication of JPS6410958B2 publication Critical patent/JPS6410958B2/ja
Granted legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/29—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the position or the direction of light beams, i.e. deflection
    • G02F1/31—Digital deflection, i.e. optical switching
    • G02F1/313—Digital deflection, i.e. optical switching in an optical waveguide structure
    • G02F1/3137—Digital deflection, i.e. optical switching in an optical waveguide structure with intersecting or branching waveguides, e.g. X-switches and Y-junctions

Landscapes

  • Physics & Mathematics (AREA)
  • Nonlinear Science (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Optical Integrated Circuits (AREA)
  • Semiconductor Lasers (AREA)

Abstract

PURPOSE:To efficiently optically couple a semiconductor laser module by connecting an optical fiber to the emitting end which does not correspond to the incident end which is connected with a semiconductor laser of a crossing type waveguide and allowing the waveguide to switch, thereby eliminating a reflecting noise. CONSTITUTION:Crossing type waveguides 21, 22 are formed by thermal diffusion of Ti on a substrate 1 which is made of Y-cut LiNbO3. Electrodes 31, 33 which oppose in parallel state are formed via a gap to the corssing part. A semiconductor laser 4 is connected with one end 21a of the waveguide 21 as an input terminal, and a non-reflecting terminal 5 is provided at the other end 21b. An optical fiber 6 of single mode is connected to the output terminal of the end 22b of the side forming a narrow angle from the terminal 5 of the other waveguide 22. When the incident light from the laser is fully reflected, and a voltage is applied between parallel electrodes 31 and 32 on the wall having low refractive index in a boundary and is made incident to the optical fiber 6.

Description

【発明の詳細な説明】 （Ｊｌ）発明の技術分野 本発明は、光通信に使用される半導体レーザと光ファイ
バーとの結合インターフェイス部に関し、結合効率の向
上を図るものである。５　　　・（ｂｌ従来技術とその
問題点 従来から行なわれているレーザ・ダイオード（以下ｒＬ
ＤＪと略す）などの半導体レーザと光ファイバーとを接
続する構成では、両者の結合部の断面形状が著しく相違
する等のために両者間の結合効率は精精５０〜６０％程
度で、これ以上の効率化は極めて困難である。またＬＤ
は反射光に弱いため、ＬＤから出射した光が光ファイバ
ーの接続部などで反射して再入射し、反射ノイズが大き
くなる問題がある。更に光変調を行なう場合、ＬＤの直
接変調では高速化が困難で、高速変調の要望に応えられ
ない。DETAILED DESCRIPTION OF THE INVENTION (Jl) Technical Field of the Invention The present invention relates to a coupling interface section between a semiconductor laser and an optical fiber used in optical communication, and is intended to improve coupling efficiency. 5 ・(bl Conventional technology and its problems) Conventional laser diode (rL)
In a configuration in which a semiconductor laser such as a DJ (abbreviated as DJ) is connected to an optical fiber, the coupling efficiency between the two is only about 50 to 60% at best, and it is difficult to achieve a higher coupling efficiency. Improving efficiency is extremely difficult. Also LD
Since the LD is sensitive to reflected light, there is a problem in that the light emitted from the LD is reflected at the connection part of the optical fiber and enters again, increasing reflection noise. Furthermore, when performing optical modulation, it is difficult to increase the speed with direct modulation of the LD, and the demand for high-speed modulation cannot be met.

（Ｃ）発明の目的 本発明は、従来のＬＤと光フアイバー間の結合インター
フェイス部におけるこのような問題を解消し、高速変調
が可能で且つ反射ノイズの影響を受けることなしに、効
率的な結合を可能にすることを目的とする。(C) Purpose of the Invention The present invention solves these problems in the conventional coupling interface between an LD and an optical fiber, enables high-speed modulation, and provides efficient coupling without being affected by reflection noise. The purpose is to make it possible.

（ｄ）発明の構成 この目的を達成するために本発明は、半導体レーザと光
ファイバーとの間にスイッチ機能を有するチタン拡散ニ
オブ酸リチウム交差路を介在させ、該チタン拡散ニオブ
酸リチウム交差路の１つの導波路の入射端に半導体レー
ザを接続し、該入射端と対応する出射端以外のもう１つ
の導波路の出射５端に光ファイバーを接続した構成を採
っている。(d) Structure of the Invention In order to achieve this object, the present invention provides a titanium-diffused lithium niobate cross-section having a switching function between the semiconductor laser and the optical fiber, and one of the titanium-diffused lithium niobate cross-sections. A semiconductor laser is connected to the input end of one waveguide, and an optical fiber is connected to the output end of another waveguide other than the output end corresponding to the input end.

＋６）発明の実施例　゛ 次に本発明による半導体レーザモジュールの実施例を説
明する。ｓｉ図は半導体レーザモジュールの実施例の平
面図である。ｌはＹカットＬｉＮｂｏ：＋にオブ酸リチ
ウム）でできた基板で、この基板１上にＴｉ　　（チタ
ン）の熱拡散により輻１０μｍ１厚さ４μｍ程度の導波
路２１．２２が構成されている。導波路２１と２２とは
、途中で交差しており、この交差部分２３に平行電極３
１，３２が形成されている。第２図はこの交差部２３を
拡大して示した平面図、第３図は１＠２図のｍ−ｍ’断
面図である。電極３１と３２は交差点の中心を境にして
、例えば２〜３μｍ程度のギャップ３３をおいて平行状
態に対向している。この電極３１゜３２は、金などの蒸
着で、導波路２１．２２の交差部２３の上に被着形成さ
れている。なお！＠３図（イ）に示されるように、導波
路２１，２２の表面が基板ｌの面と同一面になっている
場合のほか、（ロ）のように導波路２１，２２の部分だ
けが基板１の面から凸状に突出していても差支えない。+6) Embodiments of the invention ゛Next, embodiments of the semiconductor laser module according to the invention will be described. si diagram is a plan view of an embodiment of a semiconductor laser module. 1 is a substrate made of Y-cut LiNbo (lithium oxide), and waveguides 21 and 22 having a diameter of about 10 μm and a thickness of about 4 μm are formed on this substrate 1 by thermal diffusion of Ti (titanium). The waveguides 21 and 22 intersect in the middle, and a parallel electrode 3 is placed at this intersection 23.
1 and 32 are formed. FIG. 2 is an enlarged plan view of this intersection 23, and FIG. 3 is a sectional view taken along line mm' in FIG. 1@2. The electrodes 31 and 32 are parallel to each other and face each other with a gap 33 of, for example, about 2 to 3 μm between them at the center of the intersection. The electrodes 31 and 32 are formed on the intersections 23 of the waveguides 21 and 22 by vapor deposition of gold or the like. In addition! @3 In addition to the case where the surfaces of the waveguides 21 and 22 are flush with the surface of the substrate l as shown in Figure (a), there is also the case where only the waveguides 21 and 22 are There is no problem even if it protrudes convexly from the surface of the substrate 1.

導波路２１と２２は例えば３度程度の狭角度αを成して
おり、導波路２１．２２の内の１本の端部例えば２１ａ
を入力端とし、該入力端にＬＤ４が接続されている。そ
してこの導波路２１の他端２１ｂには、無反射終端５（
又はモニタ用のデテクタでもよい）が設けられている。The waveguides 21 and 22 form a narrow angle α of, for example, about 3 degrees, and the end of one of the waveguides 21 and 22, for example 21a
is an input terminal, and LD4 is connected to the input terminal. The other end 21b of this waveguide 21 is provided with a non-reflection termination 5 (
or a detector for monitoring) is provided.

またもう一方の導波路２２の、前記無反射終端５と挟角
を成す側の端部２２ｂが出力端で、この出力端２２ｂに
シングルモードの光ファイバー６が接続されている。An end 22b of the other waveguide 22 on the side forming an angle with the non-reflection termination 5 is an output end, and a single mode optical fiber 6 is connected to this output end 22b.

この構成において、ＬＤからの出射光は、平行電極３Ｌ
３２間に電圧が印加されていない状態では、導波路２１
のみを直進して他端２１ｂの出射端で無反射終端５に光
吸収される。ところが、平行電極３１．３２間に電圧を
印加すると、平行電極３１．３２間の境部に屈折率の低
い壁が出来、ＬＤから出射した光は、この壁で全反射し
てもう一方の導波路２２にガイドされ、その出力端に接
続された光ファイバー６に入射する。従って、ＬＤ４自
身の直接変調でなく、平行電極３１，３２間への電圧印
加によって光１ｕｉｉを行ない、＊調光を光ファイバー
６に伝達することができ、この平行電極３１，３２によ
る変調を高速で行なうことにより、従来のＬＤの直接変
調に比べて変調の高速化が可能となる。またこのように
平行電極３１．３２への電圧印加で、光をスイッチング
させれば、ＬＤから出射した光の反射光が光ファイバー
６から反射して来る時点では、平行電極３１，３２は電
圧が印加されていない状態となるので、反射光は境界部
３３で全反射されないで、導波路２２を直進して、他方
の端部２２ａへ逃がされる。従ってＬＤとしては、反射
光が再入射してノイズを発生することも無い。In this configuration, the light emitted from the LD is transmitted through the parallel electrode 3L.
When no voltage is applied across waveguide 21
The light travels straight through only the other end 21b and is absorbed by the non-reflection terminal 5 at the output end of the other end 21b. However, when a voltage is applied between the parallel electrodes 31 and 32, a wall with a low refractive index is formed at the boundary between the parallel electrodes 31 and 32, and the light emitted from the LD is totally reflected by this wall and passes through the other guide. The light is guided by the wave path 22 and enters the optical fiber 6 connected to its output end. Therefore, rather than direct modulation of the LD 4 itself, the light 1uii can be performed by applying a voltage between the parallel electrodes 31 and 32, and the dimming can be transmitted to the optical fiber 6, and the modulation by the parallel electrodes 31 and 32 can be performed at high speed. By doing so, it becomes possible to perform modulation at a higher speed than in the conventional direct modulation of LD. Furthermore, if the light is switched by applying voltage to the parallel electrodes 31 and 32 in this way, at the time when the reflected light emitted from the LD is reflected from the optical fiber 6, voltage is applied to the parallel electrodes 31 and 32. Therefore, the reflected light is not totally reflected at the boundary portion 33, but travels straight through the waveguide 22 and escapes to the other end portion 22a. Therefore, reflected light does not enter the LD again and generate noise.

このように交差形導波路の交差部に平行電極を設けて電
圧を印加し、屈折率の低い壁を形成してスイッチングを
行なわせるデバイスは、ＴＥモードに対しては非常に勝
れたスイッチング特性を持っており、本発明の出願人か
らすでに特許出願されている。このような高速スイッチ
ングデバイスの両端にＬＤと光ファイバーを接続すれば
、ＬＤの出射光も殆どＴＥモードであるために、ＬＤか
らの出射光を効率良く光ファイバー６に結合することが
できる。また、導波路２１，２２の断面形状を途中で次
、第に変化させて、１＠４図（ロ）に示される如く、導
波路２１の入射端２１ａの形状を、（イ）に示されるＬ
Ｄの出射面４１の形状と一致するように形成すると共に
、！＠５図に示される如く、導波路２２の出射端２２ｂ
の形状を光ファイバー６の入射端の形状と一致するよう
に形成することにより、従来のＬＤの出射面と光ファイ
バーの入射面の形状の不一致による結合効率の低下を効
果的に防止することができる。Devices that perform switching by providing parallel electrodes at the intersections of crossed waveguides and applying voltage to form walls with a low refractive index have excellent switching characteristics for the TE mode. The applicant of the present invention has already filed a patent application. If an LD and an optical fiber are connected to both ends of such a high-speed switching device, the light emitted from the LD can be efficiently coupled to the optical fiber 6 since most of the light emitted from the LD is also in the TE mode. In addition, by changing the cross-sectional shape of the waveguides 21 and 22 gradually, the shape of the input end 21a of the waveguide 21 is changed to the shape shown in (A) as shown in Figure 1@4 (B). L
It is formed to match the shape of the output surface 41 of D, and! @ As shown in Figure 5, the output end 22b of the waveguide 22
By forming the shape to match the shape of the input end of the optical fiber 6, it is possible to effectively prevent a reduction in coupling efficiency due to a mismatch in shape between the exit surface of the conventional LD and the input surface of the optical fiber.

更に導波路と基板面が同一面に揃ったデバイスでは、第
４図に示されるように、基板１には、導波路２１とＬＤ
４との結合部に、凹部７をエツチングなどで形成し、そ
の底部に金やアルミニウムなどによるメタライズで電極
８を形成し、該凹部７中にＬＤを挿入して出射光端面４
１を入射端面２１ａと対向させた状態で、電極８にＬＤ
を固定する。光ファイバー６も同様に、該光ファイバー
６が丁度嵌入できる形状の凹部９中に挿入し、その入射
端面を導波路２２の出射端２２ｂと対向させる。このよ
うな凹部への散大型とすることにより、導波路とＬＤ及
び光フアイバー相互の接続を高精度に行なうことができ
る。また第１図に示されるように、基板１の左端面と導
波路２１の入射端２１ａを導波路２１と直角に形成し、
基板ｌの右端面と導波路２２の出射端面２２ｂを導波路
ｎと直角に形成する。このような構成とすることにより
、導波路とＬＤ４および光ファイバー６との光結合が一
層効率的となり、ＬＤと光フアイバー６間の光結合がよ
り効率化される。Furthermore, in a device where the waveguide and the substrate surface are on the same plane, as shown in FIG.
4, a recess 7 is formed by etching or the like, and an electrode 8 is formed at the bottom of the recess 7 by metallization of gold, aluminum, etc., and an LD is inserted into the recess 7, and the output light end face 4 is formed.
1 facing the incident end surface 21a, the LD is connected to the electrode 8.
to be fixed. Similarly, the optical fiber 6 is inserted into a recess 9 having a shape that allows the optical fiber 6 to fit therein, and its input end face is opposed to the output end 22b of the waveguide 22. By increasing the size of the concave portion, the waveguide, LD, and optical fiber can be interconnected with high precision. Further, as shown in FIG. 1, the left end surface of the substrate 1 and the input end 21a of the waveguide 21 are formed at right angles to the waveguide 21,
The right end surface of the substrate l and the output end surface 22b of the waveguide 22 are formed at right angles to the waveguide n. With such a configuration, the optical coupling between the waveguide, the LD 4 and the optical fiber 6 becomes more efficient, and the optical coupling between the LD and the optical fiber 6 becomes more efficient.

なおこの構成において、平行電極３１．３２には直流電
圧を印加してＬＤからの光は総て光ファイバー６へ伝達
されるようにした状態で、ＬＤ自身を直接ｇＩＬ調する
こともでき、アナログ信号の場合に有効である。In this configuration, by applying a DC voltage to the parallel electrodes 31 and 32 so that all the light from the LD is transmitted to the optical fiber 6, the LD itself can be directly adjusted to gIL, and the analog signal can be adjusted. It is valid in the case of

（ｆ１発明の効果 以上のように本発明によれば、半導体レーザと光ファイ
バーとの間にスイッチ機能を有するチタン拡散ニオブ酸
リチウム交差路を介在させ、該チタン拡散ニオブ酸リチ
ウム交差路の１つの導波路の入射端に半導体レーザを接
続し、該入射端と対応する出射端以外のもう１つの導波
路の出射端に光ファイバーを接続した構成になっている
。そのためスイッチングによる高速外部変調が容易で、
且つ反射ノイズを受けず、またＬＤと光ファイバーとの
間に、チタン拡散ニオブ酸リチウム交差路を介在させる
ことにより、ＬＤと光ファイバーとの光結合の効率化が
実現できる。(f1 Effects of the Invention As described above, according to the present invention, a titanium-diffused lithium niobate cross-section having a switching function is interposed between the semiconductor laser and the optical fiber, and one conductor of the titanium-diffused lithium niobate cross-path is provided between the semiconductor laser and the optical fiber. The configuration is such that a semiconductor laser is connected to the input end of the waveguide, and an optical fiber is connected to the output end of another waveguide other than the output end corresponding to the input end.Therefore, high-speed external modulation by switching is easy.
In addition, by interposing a titanium-diffused lithium niobate crossroad between the LD and the optical fiber without receiving reflection noise, the optical coupling between the LD and the optical fiber can be made more efficient.

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

図は本発明の実施例を示すもので、ｉｔ図は半導体レー
ザモジュールの平面図、第２図はその交差部の拡大平面
図、第３図は１＠２図のｍ−ｍ’断面図、ｇＪ４図は導
波路とＬＤとの結合部を示す図、！＠５図は導波路と光
ファイバーとの結合部を示す図である。 図において、■は基板、２１，２２は導波路、２３は交
差部、２１ａは入射端、２２ｂは出射端、３１．３２は
平行電極、４はＬＤ、４１は出射面、６は光ファイバー
を夫々示す。 特許出願人　　　　　　富士通株式会社代理人　弁理士
　　　　青　柳　　　稔第１図 第２図 第３図 （）Ｘ） 第５図 手続補正書 昭和５７年５月２４　　日 特許庁長官　島　１）春　樹　殿 １、事件の表示　　　特願昭５６−２１０６５０２、発
明の名称　　　半導体レーザモジュール３、補正をする
者 事件との関係　特許出願人 住所　　　　　神奈川県用崎市中原区上小田中１０１５
番地鋳　　（５２２）富士通株式会社 代表者山本　車色 ４、代理人　　　　　〒１０１１１　（０３）　８６３
−０２２０１、柿止の同容　　　別蝋のと石り １、明細書の第７頁第１８行から第１９行の「直接変調
することもでき、アナログ信号の場合に有効である。」
の記載を、「直接変調することもできる。」と補正する
。The figures show an embodiment of the present invention, in which the IT diagram is a plan view of the semiconductor laser module, FIG. 2 is an enlarged plan view of the intersection, FIG. Figure gJ4 is a diagram showing the coupling part between the waveguide and the LD,! @Figure 5 is a diagram showing a coupling portion between a waveguide and an optical fiber. In the figure, ■ is the substrate, 21 and 22 are the waveguides, 23 is the intersection, 21a is the input end, 22b is the output end, 31.32 is the parallel electrode, 4 is the LD, 41 is the output surface, and 6 is the optical fiber. show. Patent Applicant Fujitsu Limited Agent Patent Attorney Minoru Aoyagi Figure 1 Figure 2 Figure 3 () Indication of the case: Japanese Patent Application No. 56-2106502, title of the invention: Semiconductor laser module 3, person making the amendment Relationship to the case: Patent applicant address: 1015 Kamiodanaka, Nakahara-ku, Yozaki City, Kanagawa Prefecture
Banchi Chu (522) Fujitsu Limited Representative Yamamoto Kurama 4, Agent 10111 (03) 863
-02201, Kakitome's same name Betsuro no Tostoneri 1, page 7, lines 18 to 19 of the specification: "Direct modulation is also possible and is effective in the case of analog signals."
The statement in ``can also be directly modulated'' has been corrected.

Claims (1)

【特許請求の範囲】[Claims] 半導体レーザと光ファイバーとの間にスイッチ機能を有
するチタン拡散ニオブ酸リチウム交差路を介在させ、該
チタン拡散ニオブ酸リチウム交差路の１つの導波路の入
射端に半導体レーザを接続し、該入射端と対応する出射
端以外のもう１つの導波路の出射端に光ファイバーを接
続したことを特徴とする半導体レーザモジュール。A titanium-diffused lithium niobate crossroad having a switching function is interposed between the semiconductor laser and the optical fiber, and the semiconductor laser is connected to the input end of one waveguide of the titanium-diffused lithium niobate crossroad, and A semiconductor laser module characterized in that an optical fiber is connected to an output end of another waveguide other than the corresponding output end.
JP21065081A 1981-12-30 1981-12-30 Semiconductor laser module Granted JPS58116784A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP21065081A JPS58116784A (en) 1981-12-30 1981-12-30 Semiconductor laser module

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP21065081A JPS58116784A (en) 1981-12-30 1981-12-30 Semiconductor laser module

Publications (2)

Publication Number Publication Date
JPS58116784A true JPS58116784A (en) 1983-07-12
JPS6410958B2 JPS6410958B2 (en) 1989-02-22

Family

ID=16592815

Family Applications (1)

Application Number Title Priority Date Filing Date
JP21065081A Granted JPS58116784A (en) 1981-12-30 1981-12-30 Semiconductor laser module

Country Status (1)

Country Link
JP (1) JPS58116784A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0436346A2 (en) * 1990-01-04 1991-07-10 SMITHS INDUSTRIES AEROSPACE & DEFENSE SYSTEMS INC. Optical switches
WO2009145199A1 (en) * 2008-05-26 2009-12-03 日本電信電話株式会社 Waveguide type device and module

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0436346A2 (en) * 1990-01-04 1991-07-10 SMITHS INDUSTRIES AEROSPACE & DEFENSE SYSTEMS INC. Optical switches
WO2009145199A1 (en) * 2008-05-26 2009-12-03 日本電信電話株式会社 Waveguide type device and module
US8625943B2 (en) 2008-05-26 2014-01-07 Nippon Telegraph And Telephone Corporation Waveguide device and module

Also Published As

Publication number Publication date
JPS6410958B2 (en) 1989-02-22

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