JPH04355416A - Waveguide route type optical device - Google Patents
Waveguide route type optical deviceInfo
- Publication number
- JPH04355416A JPH04355416A JP13015191A JP13015191A JPH04355416A JP H04355416 A JPH04355416 A JP H04355416A JP 13015191 A JP13015191 A JP 13015191A JP 13015191 A JP13015191 A JP 13015191A JP H04355416 A JPH04355416 A JP H04355416A
- Authority
- JP
- Japan
- Prior art keywords
- waveguide
- semiconductor laser
- optical device
- lens
- type optical
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 230000003287 optical effect Effects 0.000 title claims abstract description 42
- 239000004065 semiconductor Substances 0.000 claims abstract description 36
- 239000000758 substrate Substances 0.000 claims abstract description 30
- 239000011521 glass Substances 0.000 abstract description 5
- 238000005498 polishing Methods 0.000 abstract description 2
- 239000013307 optical fiber Substances 0.000 description 7
- 230000000694 effects Effects 0.000 description 5
- NJPPVKZQTLUDBO-UHFFFAOYSA-N novaluron Chemical compound C1=C(Cl)C(OC(F)(F)C(OC(F)(F)F)F)=CC=C1NC(=O)NC(=O)C1=C(F)C=CC=C1F NJPPVKZQTLUDBO-UHFFFAOYSA-N 0.000 description 4
- 230000008878 coupling Effects 0.000 description 3
- 238000010168 coupling process Methods 0.000 description 3
- 238000005859 coupling reaction Methods 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- 239000000853 adhesive Substances 0.000 description 2
- 230000001070 adhesive effect Effects 0.000 description 2
- 229910003327 LiNbO3 Inorganic materials 0.000 description 1
- 230000008033 biological extinction Effects 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 229910052681 coesite Inorganic materials 0.000 description 1
- 230000008602 contraction Effects 0.000 description 1
- 229910052906 cristobalite Inorganic materials 0.000 description 1
- 230000002542 deteriorative effect Effects 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000000059 patterning Methods 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
- 235000012239 silicon dioxide Nutrition 0.000 description 1
- 229910052682 stishovite Inorganic materials 0.000 description 1
- 229910052905 tridymite Inorganic materials 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
Landscapes
- Optical Integrated Circuits (AREA)
- Semiconductor Lasers (AREA)
- Optical Couplings Of Light Guides (AREA)
Abstract
Description
【0001】0001
【産業上の利用分野】本発明は導波路型光デバイスに関
し、特に導波路とこれにレンズを介して光学的に結合す
る半導体レーザとを有してなる導波路型光デバイスの光
軸固定構造に関する。[Field of Industrial Application] The present invention relates to a waveguide type optical device, and more particularly to an optical axis fixing structure for a waveguide type optical device comprising a waveguide and a semiconductor laser optically coupled to the waveguide via a lens. Regarding.
【0002】0002
【従来の技術】一般に、導波路型光デバイスは、強誘電
体基板や、半導体基板中に光の導波部分(導波路)とな
る周辺より屈折率の高い領域を形成し、この導波路の上
部または近傍に電極が形成されていて、この電極に電圧
を印加して基板のもつ電気光学効果等の性質を用いて、
導波路の屈折率を変化させて、光の位相や強度を制御あ
るいは変調する光デバイスである。例えば、このような
導波路型光デバイスとして高い電気光学効果を有するL
iNbO3 基板にTiを所望の導波路パターンのパタ
ーニングと熱拡散して導波路を形成し、電極を設けて光
の強度を高速に変調する光デバイスがある。[Prior Art] Generally, a waveguide type optical device forms a region in a ferroelectric substrate or a semiconductor substrate that has a higher refractive index than the periphery that serves as a light waveguide portion (waveguide). An electrode is formed on or near the top, and a voltage is applied to this electrode to utilize the electro-optic effect and other properties of the substrate.
It is an optical device that controls or modulates the phase and intensity of light by changing the refractive index of a waveguide. For example, L, which has a high electro-optic effect as such a waveguide type optical device,
There is an optical device in which a waveguide is formed by patterning and thermally diffusing Ti into a desired waveguide pattern on an iNbO3 substrate, and electrodes are provided to rapidly modulate the intensity of light.
【0003】これは、光通信分野において現在の半導体
レーザを直接変調する方式から、さらに大容量、高速化
するために半導体レーザから発振された光を外部に設け
た強度変調器で高速変調するための外部変調器で、国内
外で広く研究開発されている。[0003] In the field of optical communications, the current method of directly modulating a semiconductor laser has been changed to a method in which the light oscillated from the semiconductor laser is modulated at high speed using an external intensity modulator in order to achieve higher capacity and higher speed. This is an external modulator that has been widely researched and developed both domestically and internationally.
【0004】こうした半導体レーザと導波路が一体とな
った導波路型光デバイスを実現する場合、(a)半導体
レーザからの光を高効率で導波路に結合する。(b)半
導体レーザの光が導波路以外の基板に迷失として漏れこ
むのを少なくする。(c)光軸固定部を安定化させる。
ことが重要となる。[0004] When realizing a waveguide-type optical device in which a semiconductor laser and a waveguide are integrated, (a) light from the semiconductor laser is coupled to the waveguide with high efficiency. (b) Reduce the possibility that the light from the semiconductor laser will leak into the substrate other than the waveguide as a stray. (c) Stabilize the optical axis fixing part. That is important.
【0005】こうした光源となる半導体レーザと、半導
体レーザから出射された光を導波路に収束させるレンズ
と、導波路基板を固定する構造を有する従来の導波路型
光デバイスの第1の例を図2に示す。A first example of a conventional waveguide type optical device having a structure for fixing a semiconductor laser as a light source, a lens for converging light emitted from the semiconductor laser onto a waveguide, and a waveguide substrate is shown in FIG. Shown in 2.
【0006】図2において、この第1の例の導波路型光
デバイスは半導体レーザ5と、レンズ4と、導波路基板
1とを金属の筺体9にレンズを固定する台座10、およ
びLDパッケージを固定する台座11を用いてそれぞれ
光学的に結合させた後に、独立に固定する構造を有して
いる。例えば、あらかじめ筺体9に導波路基板1を固着
し、その端面近傍にレンズ4がくるように位置決めし、
レンズ4を筺体9に固定する。そして最後に半導体レー
ザ5を実装したLDパッケージ7を光軸調整し、これを
筺体9にレーザ溶接等の工法を用いて固定する。In FIG. 2, the waveguide type optical device of the first example includes a semiconductor laser 5, a lens 4, a waveguide substrate 1, a pedestal 10 for fixing the lens to a metal casing 9, and an LD package. They have a structure in which they are each optically coupled using a fixing pedestal 11 and then fixed independently. For example, the waveguide substrate 1 is fixed to the housing 9 in advance, and the lens 4 is positioned near the end face of the waveguide substrate 1,
The lens 4 is fixed to the housing 9. Finally, the optical axis of the LD package 7 mounted with the semiconductor laser 5 is adjusted, and it is fixed to the housing 9 using a method such as laser welding.
【0007】図3は従来の導波路型光デバイスの第2の
例を示す断面図である。FIG. 3 is a sectional view showing a second example of a conventional waveguide type optical device.
【0008】図3において、この第2の例の導波路型光
デバイスは、半導体レーザ5からの出射光をレンズ4を
用いて収束させる構造でなく、直接、導波路に結合させ
る構造となっている。ところが、この構造の場合、導波
路端面と半導体レーザの出射部の距離を10〜50μm
程度に近づけても、上述のレンズを用いた第1の例の場
合に比べ、結合効率が悪い。また、導波路に結合しなか
った光は、導波路基板内に入り込み、これが出力側の光
ファイバに漏れ込み、デバイスの消光比を極端に劣化さ
せてしまう。こうしたことから図2に示す第1の従来例
が適用されている。In FIG. 3, the waveguide type optical device of this second example has a structure in which the emitted light from the semiconductor laser 5 is not converged using the lens 4, but is directly coupled to the waveguide. There is. However, in the case of this structure, the distance between the waveguide end face and the emission part of the semiconductor laser is 10 to 50 μm.
Even if the coupling efficiency is close to that level, the coupling efficiency is lower than that of the first example using the above-mentioned lens. Furthermore, the light that has not been coupled to the waveguide enters the waveguide substrate and leaks into the output optical fiber, extremely deteriorating the extinction ratio of the device. For this reason, the first conventional example shown in FIG. 2 is applied.
【0009】[0009]
【発明が解決しようとする課題】上述した従来の導波路
型光デバイスは、半導体レーザと導波路との双方が筺体
を介して光軸固定されているために、温度変化が生じる
と、導波路基板と筺体、あるいは半導体レーザを実装し
たパッケージと筺体との熱膨張係数差により相対的な位
置ずれを生じ、光軸ずれによる損失増加を起こしやすい
という問題点がある。特に、導波路基板が大きく基板と
筺体との固着部分が広い場合にはこの傾向は顕著になり
、また、筺体に外部から力が作用すると、筺体が変形し
、同様に光軸ずれによる損失増加を招いてしまうという
問題点がある。[Problems to be Solved by the Invention] In the conventional waveguide type optical device described above, since the optical axis of both the semiconductor laser and the waveguide is fixed through the housing, when a temperature change occurs, the waveguide There is a problem in that a relative positional shift occurs due to the difference in thermal expansion coefficient between the substrate and the casing, or between the package on which the semiconductor laser is mounted and the casing, which tends to cause an increase in loss due to optical axis misalignment. This tendency is particularly noticeable when the waveguide substrate is large and the fixed area between the substrate and the housing is wide. Also, when force is applied to the housing from the outside, the housing deforms and loss increases due to optical axis misalignment. The problem is that it invites
【0010】一方、導波路への半導体レーザ光の結合を
行う場合も、光軸調整作業を筺体内部で行う必要がある
ため、作業性が悪いという問題点がある。On the other hand, when coupling the semiconductor laser light to the waveguide, there is a problem in that the workability is poor because the optical axis adjustment work must be performed inside the housing.
【0011】[0011]
【課題を解決するための手段】本発明の導波路型光デバ
イスは、基板中に導波路が形成された導波路基板と、前
記導波路にレンズを介し光学的に結合する半導体レーザ
とからなる導波路型光デバイスにおいて、前記半導体レ
ーザと前記レンズとがフランジ付パイプのフランジ面で
結像するように予め位置調整されて収容され、前記フラ
ンジ付パイプのフランジ面と前記導波路基板の端面とが
密着され、前記フランジ付パイプのフランジ面に結像さ
れた前記半導体レーザのスポットが前記導波路に入射す
るように予め位置調整されて固定されて成っている。[Means for Solving the Problems] A waveguide type optical device of the present invention includes a waveguide substrate in which a waveguide is formed, and a semiconductor laser optically coupled to the waveguide through a lens. In the waveguide type optical device, the semiconductor laser and the lens are housed with their positions adjusted in advance so that an image is formed on the flange surface of the flanged pipe, and the flange surface of the flanged pipe and the end surface of the waveguide substrate are in close contact with each other, and the spot of the semiconductor laser imaged on the flange surface of the flanged pipe is adjusted and fixed in advance so that the spot is incident on the waveguide.
【0012】0012
【実施例】次に、本発明について図面を参照して説明す
る。DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be explained with reference to the drawings.
【0013】図1は本発明の一実施例の導波路型光デバ
イスの縦断面図である。FIG. 1 is a longitudinal sectional view of a waveguide type optical device according to an embodiment of the present invention.
【0014】図1において、本実施例の導波路型光デバ
イス20は、高い電気光学効果を有するLiNbO3
基板にTi膜により形成された導波路パターンを100
0°C6時間熱拡散して導波路を形成し、この導波路の
上部にSiO2 バッファ層を介して電極が形成されて
おり、電極に電圧を外部から印加することにより、光の
位相を制御,あるいは変調することができる位相変調器
である。In FIG. 1, the waveguide type optical device 20 of this embodiment is made of LiNbO3, which has a high electro-optic effect.
100 waveguide patterns formed on a substrate using a Ti film.
A waveguide is formed by thermal diffusion at 0°C for 6 hours, and an electrode is formed on the top of this waveguide via a SiO2 buffer layer.By applying a voltage to the electrode from the outside, the phase of the light can be controlled. Alternatively, it is a phase modulator that can be modulated.
【0015】本実施例の導波路型光デバイス20は導波
路基板1に上ヤトイ2を両端の上面に、また、保持ガラ
ス3を下部にそれぞれ接着剤で貼付けた後、両端面を研
磨し、各端面に光源となる半導体レーザ5と光ファイバ
12とが光学的に結合されている。ここで、光ファイバ
12はフランジ付パイプ6に収容されており、光ファイ
バ12の端面は導波路基板1の端面に直接あてられ、予
め光軸調整された後、フランジ付パイプ6のフランジ面
と導波路基板1の端面どうしが密着されて固着されてい
る。一方、半導体レーザ5は、LDパッケージ7に収容
されており、予めレンズ4を収容したフランジ付パイプ
6と位置調整し、密着面を半導体レーザ5により固着し
ている。このユニットをフランジ付パイプ6のフランジ
面を導波路基板1の端面に密着させて光軸調整した後に
固着してある。The waveguide type optical device 20 of this embodiment is made by attaching the upper coating 2 to the upper surface of both ends of the waveguide substrate 1 and the holding glass 3 to the lower part thereof with adhesive, and then polishing both end surfaces. A semiconductor laser 5 serving as a light source and an optical fiber 12 are optically coupled to each end face. Here, the optical fiber 12 is housed in the flanged pipe 6, and the end face of the optical fiber 12 is directly applied to the end face of the waveguide substrate 1, and after the optical axis is adjusted in advance, the flange face of the flanged pipe 6 and The end faces of the waveguide substrate 1 are closely attached and fixed to each other. On the other hand, the semiconductor laser 5 is housed in the LD package 7, and its position is adjusted in advance with the flanged pipe 6 in which the lens 4 is housed, and the semiconductor laser 5 is fixed to the contact surface. This unit is fixed by bringing the flange surface of the flanged pipe 6 into close contact with the end surface of the waveguide substrate 1 and adjusting the optical axis.
【0016】尚、導波路端面はここでの反射光が半導体
レーザ5へ戻るのを防ぐため、斜めに端面研磨している
。最後に、これら、導波路基板1と光ファイバ12と半
導体レーザ5とが一体化された光学ユニットを筺体9に
保持ガラス3の底面を接着して、実装している。Note that the end face of the waveguide is polished obliquely to prevent reflected light from returning to the semiconductor laser 5. Finally, the optical unit in which the waveguide substrate 1, the optical fiber 12, and the semiconductor laser 5 are integrated is mounted on the housing 9 by bonding the bottom surface of the holding glass 3.
【0017】次に、本実施例の実験結果の一例について
説明する。Next, an example of the experimental results of this example will be explained.
【0018】図1に示す本実施例と図2に示す第1の従
来例の導波路型光デバイスとの温度サイクル試験を行い
、−26〜70°Cの温度範囲で1000サイクル印加
した後の光ファイバ出力を評価すると、本実施例では初
期に比べ、0.5dBしか劣化していないのに対し、図
2に示す第1の従来例では、約3dBの劣化があった。
第1の従来例のLDパッケージ7をいったん筺体9から
はずし、光軸を再調整すると、再び初期の状態に戻った
。こうしたことから本実施例では光軸固定部は安定し、
一方第1の従来例では光軸固定部が不安定で、信頼性が
低いことがわかる。A temperature cycle test was conducted on the present embodiment shown in FIG. 1 and the first conventional waveguide type optical device shown in FIG. When evaluating the optical fiber output, in this example, it was degraded by only 0.5 dB compared to the initial state, whereas in the first conventional example shown in FIG. 2, it was degraded by about 3 dB. Once the LD package 7 of the first conventional example was removed from the housing 9 and the optical axis was readjusted, it returned to its initial state again. For this reason, in this example, the optical axis fixing part is stable,
On the other hand, it can be seen that in the first conventional example, the optical axis fixing part is unstable and the reliability is low.
【0019】[0019]
【発明の効果】以上説明したように本発明は、導波路基
板,半導体レーザ及びレンズを筺体上で独立に固着する
のでなく、フランジ付パイプを利用してこれに収容され
た半導体レーザとレンズとを直接導波路基板の端面に固
着させる構造となっているので、導波路基板と筺体との
熱膨張係数差や、固着部分の接着剤の伸縮,筺体の外力
による変形等の影響を受けないので、光軸ずれが生じに
くく、光学的に安定し、高い信頼性が得られるという効
果を有する。Effects of the Invention As explained above, the present invention does not fix the waveguide substrate, the semiconductor laser, and the lens independently on the housing, but uses a flanged pipe to accommodate the semiconductor laser and the lens. Because it has a structure in which it is directly fixed to the end face of the waveguide substrate, it is not affected by the difference in thermal expansion coefficient between the waveguide substrate and the housing, the expansion and contraction of the adhesive at the fixed part, and the deformation of the housing due to external force. , it has the effect that optical axis deviation is less likely to occur, optically stable, and high reliability can be obtained.
【図面の簡単な説明】[Brief explanation of drawings]
【図1】本発明の一実施例を示す縦断面図である。FIG. 1 is a longitudinal sectional view showing an embodiment of the present invention.
【図2】従来の導波路型光デバイスの第1の例を示す縦
断面図である。FIG. 2 is a longitudinal cross-sectional view showing a first example of a conventional waveguide type optical device.
【図3】従来の導波路型光デバイスの第2の例を示す縦
断面図である。FIG. 3 is a vertical cross-sectional view showing a second example of a conventional waveguide type optical device.
1 導波路基板
2 上ヤトイ
3 保持ガラス
4 レンズ
5 半導体レーザ(半導体LD)6 フラ
ンジ付パイプ
7 LDパッケージ
8 半導体LD端子
9 筺体
10 レンズ固定台座
11 LDパッケージ固定台座
12 光ファイバ
20 導波路型光デバイス1 Waveguide substrate 2 Upper Yatoi 3 Holding glass 4 Lens 5 Semiconductor laser (semiconductor LD) 6 Pipe with flange 7 LD package 8 Semiconductor LD terminal 9 Housing 10 Lens fixing pedestal 11 LD package fixing pedestal 12 Optical fiber 20 Waveguide type optical device
Claims (1)
板と、前記導波路にレンズを介し光学的に結合する半導
体レーザとからなる導波路型光デバイスにおいて、前記
半導体レーザと前記レンズとがフランジ付パイプのフラ
ンジ面で結像するように予め位置調整されて収容され、
前記フランジ付パイプのフランジ面と前記導波路基板の
端面とが密着され、前記フランジ付パイプのフランジ面
に結像された前記半導体レーザのスポットが前記導波路
に入射するように予め位置調整されて固定されて成るこ
とを特徴とする導波路型光デバイス。1. A waveguide type optical device comprising a waveguide substrate in which a waveguide is formed, and a semiconductor laser optically coupled to the waveguide via a lens, wherein the semiconductor laser and the lens are connected to each other. is housed in a position adjusted in advance so that the image is formed on the flange surface of the flanged pipe,
The flange surface of the flanged pipe and the end surface of the waveguide substrate are brought into close contact with each other, and the position is adjusted in advance so that the spot of the semiconductor laser focused on the flange surface of the flanged pipe is incident on the waveguide. A waveguide type optical device characterized in that it is fixed.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP3130151A JP2803390B2 (en) | 1991-06-03 | 1991-06-03 | Waveguide type optical device |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP3130151A JP2803390B2 (en) | 1991-06-03 | 1991-06-03 | Waveguide type optical device |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH04355416A true JPH04355416A (en) | 1992-12-09 |
JP2803390B2 JP2803390B2 (en) | 1998-09-24 |
Family
ID=15027206
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP3130151A Expired - Lifetime JP2803390B2 (en) | 1991-06-03 | 1991-06-03 | Waveguide type optical device |
Country Status (1)
Country | Link |
---|---|
JP (1) | JP2803390B2 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2008216682A (en) * | 2007-03-05 | 2008-09-18 | Sumitomo Osaka Cement Co Ltd | Optical equipment |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5623911U (en) * | 1979-07-30 | 1981-03-04 | ||
JPH0233114A (en) * | 1988-07-22 | 1990-02-02 | Matsushita Electric Ind Co Ltd | Light emission module |
-
1991
- 1991-06-03 JP JP3130151A patent/JP2803390B2/en not_active Expired - Lifetime
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5623911U (en) * | 1979-07-30 | 1981-03-04 | ||
JPH0233114A (en) * | 1988-07-22 | 1990-02-02 | Matsushita Electric Ind Co Ltd | Light emission module |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2008216682A (en) * | 2007-03-05 | 2008-09-18 | Sumitomo Osaka Cement Co Ltd | Optical equipment |
Also Published As
Publication number | Publication date |
---|---|
JP2803390B2 (en) | 1998-09-24 |
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