JPS6412367B2 - - Google Patents
Info
- Publication number
- JPS6412367B2 JPS6412367B2 JP7124083A JP7124083A JPS6412367B2 JP S6412367 B2 JPS6412367 B2 JP S6412367B2 JP 7124083 A JP7124083 A JP 7124083A JP 7124083 A JP7124083 A JP 7124083A JP S6412367 B2 JPS6412367 B2 JP S6412367B2
- Authority
- JP
- Japan
- Prior art keywords
- optical waveguide
- interference type
- type optical
- waveguide body
- axis
- 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.)
- Expired
Links
- 230000003287 optical effect Effects 0.000 claims description 58
- 239000013307 optical fiber Substances 0.000 claims description 19
- 230000010287 polarization Effects 0.000 claims description 19
- 239000000758 substrate Substances 0.000 claims description 19
- 230000005540 biological transmission Effects 0.000 claims description 13
- 230000005684 electric field Effects 0.000 claims description 7
- 238000005253 cladding Methods 0.000 claims description 5
- 238000010586 diagram Methods 0.000 description 7
- 230000000694 effects Effects 0.000 description 5
- 230000008878 coupling Effects 0.000 description 4
- 238000010168 coupling process Methods 0.000 description 4
- 238000005859 coupling reaction Methods 0.000 description 4
- 239000013078 crystal Substances 0.000 description 4
- 239000010936 titanium Substances 0.000 description 3
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- GQYHUHYESMUTHG-UHFFFAOYSA-N lithium niobate Chemical compound [Li+].[O-][Nb](=O)=O GQYHUHYESMUTHG-UHFFFAOYSA-N 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 239000000382 optic material Substances 0.000 description 2
- 230000010363 phase shift Effects 0.000 description 2
- 229910052719 titanium Inorganic materials 0.000 description 2
- WSMQKESQZFQMFW-UHFFFAOYSA-N 5-methyl-pyrazole-3-carboxylic acid Chemical compound CC1=CC(C(O)=O)=NN1 WSMQKESQZFQMFW-UHFFFAOYSA-N 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 230000000295 complement effect Effects 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 230000002452 interceptive effect Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
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
- G02F1/01—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 intensity, phase, polarisation or colour
- G02F1/21—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 intensity, phase, polarisation or colour by interference
- G02F1/225—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 intensity, phase, polarisation or colour by interference in an optical waveguide structure
Landscapes
- Physics & Mathematics (AREA)
- Nonlinear Science (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Optical Integrated Circuits (AREA)
Description
【発明の詳細な説明】
本発明は、光変調装置に関するものであつて、
詳しくは、分岐干渉形光導波路体を通過する光を
強度変調するように構成された光変調装置の改良
に関するものであり、光源の出力変動、伝送体自
体の特性変化、光の伝送損失などを簡単な構成で
補償でき、さらに、温度変化の影響が小さく、大
きな出力信号を得ることができる装置を提供する
ものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a light modulation device, and includes:
More specifically, it relates to the improvement of an optical modulation device configured to intensity-modulate light passing through a branched interference type optical waveguide body, and is designed to reduce the output fluctuations of the light source, changes in the characteristics of the transmission body itself, optical transmission loss, etc. It is an object of the present invention to provide a device that can perform compensation with a simple configuration, is less affected by temperature changes, and can obtain a large output signal.
ニオブ酸リチウム（LiNbO0）のような電気光
学材料よりなる基板にチタンTiなどの金属不純
物を熱拡散することにより基板よりも屈折率の高
い光導波路が形成され、電気光学効果の効率の極
めて高い光導波路体が得られる。このような光導
波路に電界を加えると、光導波路を通過する光は
電気光学効果により強度変調される。 By thermally diffusing metal impurities such as titanium onto a substrate made of an electro-optic material such as lithium niobate (LiNbO 0 ), an optical waveguide with a higher refractive index than the substrate is formed, resulting in extremely high efficiency of the electro-optic effect. An optical waveguide body is obtained. When an electric field is applied to such an optical waveguide, the intensity of light passing through the optical waveguide is modulated by the electro-optic effect.
このような光導波路体の一種に、第１図に示す
ような分岐干渉形光導波路体がある。 One type of such an optical waveguide body is a branching interference type optical waveguide body as shown in FIG.
第１図において、１０は基板、２０は光導波
路、３０は電極、４０は信号源である。 In FIG. 1, 10 is a substrate, 20 is an optical waveguide, 30 is an electrode, and 40 is a signal source.
基板１０は電気光学効果を有するニオブ酸リチ
ウム（LiNbO0）のような電気光学材料で構成さ
れたものであり、Ｘ、Ｚ軸が水平面となりＹ軸が
垂直面となるようにカツトされている。光導波路
２０は基板１０にチタン（Ti）のような金属不
純物を熱拡散することにより線状に形成され基板
１０よりも高い屈折率を有するものであり、Ｙ字
形の分岐部２１、互いに平行な位相推移部２２及
びＹ字形の結合部２３が連続的に一体化されてい
る。電極３０は光導波路２０を通過する光を強度
変調するために光導波路２０に電界を印加するも
のであり、位相推移部２２を挟むようにして第１
の電極３１及び第２の電極３２が基板１０上に設
けられている。信号源４０は電界を供給するもの
であり、第１の電極３１と第２の電極３２との間
に接続されている。なお、光導波路２０のＹ字形
の分岐部２１の端部にはレーザダイオードなどの
光源からの光を伝送するための光フアイバーが接
続され、Ｙ字形の結合部２３の端部には強度変調
された光をフオトトランジスタなどの受光素子に
伝送するための光フアイバーが接続されるが図示
しない。 The substrate 10 is made of an electro-optic material such as lithium niobate (LiNbO 0 ) having an electro-optic effect, and is cut so that the X and Z axes are horizontal planes and the Y axis is a vertical plane. The optical waveguide 20 is formed into a linear shape by thermally diffusing metal impurities such as titanium (Ti) into the substrate 10, and has a higher refractive index than the substrate 10. The phase shift section 22 and the Y-shaped coupling section 23 are continuously integrated. The electrodes 30 apply an electric field to the optical waveguide 20 in order to intensity-modulate the light passing through the optical waveguide 20.
An electrode 31 and a second electrode 32 are provided on the substrate 10. The signal source 40 supplies an electric field and is connected between the first electrode 31 and the second electrode 32. An optical fiber for transmitting light from a light source such as a laser diode is connected to the end of the Y-shaped branch 21 of the optical waveguide 20, and an intensity-modulated fiber is connected to the end of the Y-shaped coupling part 23. An optical fiber for transmitting the light to a light receiving element such as a phototransistor is connected, but is not shown.
このような構成において、光導波路２０のＹ字
形の分岐部２１の端部に光源からの光が加えらる
と、光は分岐部２１で２分割されて位相推移部２
２に伝送される。位相推移部２２では２分割され
た光の間に電極３０を介して加えられる信号源４
０の出力の大きさに応じた位相差が与えられる。
そして、位相差を有するこれら光は結合部２３で
再び結合される。これにより、結合部２３の端部
から強度変調された光が送出されることになる。
ここで、位相推移部２２にλ／４の位相差を与え
て強度変調された光を受光素子に加えることによ
り電極３０を介して加えられる信号源４０の出力
の大きさに応じた電気信号を得ることができる。 In such a configuration, when light from a light source is applied to the end of the Y-shaped branch 21 of the optical waveguide 20, the light is split into two by the branch 21 and sent to the phase shifter 2.
2. In the phase shifting unit 22, a signal source 4 is applied between the two divided lights via an electrode 30.
A phase difference is given according to the magnitude of the zero output.
Then, these lights having a phase difference are combined again at the coupling part 23. As a result, intensity-modulated light is sent out from the end of the coupling section 23.
Here, by applying a phase difference of λ/4 to the phase shifter 22 and applying intensity-modulated light to the light receiving element, an electric signal corresponding to the magnitude of the output of the signal source 40 applied via the electrode 30 is generated. Obtainable.
ところで、一般にこのような装置では、光伝送
時の損失、伝送体自体の特性変化、光源の出力光
の変動などにより測定誤差を生じるという欠点が
ある。特に、従来、このような分岐干渉形光導波
路体との間で光の伝送を行う伝送体としては、伝
送体を通過する過程において偏波面が変化するお
それのある光フアイバーが用いられているので、
光フアイバーに振動や外力が加わつて光フアイバ
ーの配置状態が変化すると偏波面が変化して強度
変調誤差を生じるという問題点がある。また、出
力信号が比較的小さく、光をＸ軸方向に通過させ
ているので温度変化の影響を受けやすい。 However, such devices generally have the disadvantage that measurement errors occur due to losses during optical transmission, changes in the characteristics of the transmission body itself, fluctuations in the output light of the light source, and the like. In particular, optical fibers have traditionally been used to transmit light between such branched interference type optical waveguides, since the plane of polarization may change during the process of passing through the transmission body. ,
There is a problem in that when vibration or external force is applied to the optical fiber and the arrangement of the optical fiber changes, the polarization plane changes and an intensity modulation error occurs. Furthermore, since the output signal is relatively small and the light is passed in the X-axis direction, it is susceptible to temperature changes.
本発明は、このような従来の欠点を解決したも
のであり、Ｚ軸を中心にしてＸ軸及びＹ軸を45度
回転させた面が水平面となるようにカツトされた
基板で構成された分岐干渉形光導波路体と定偏波
光フアイバーとを組み合わせ、光源の出力変動、
伝送体自体の特性変化、光の伝送損失などを簡単
な構成で補償でき、さらに、温度変化の影響が小
さく、大きな出力信号を得ることができる装置を
提供するものである。 The present invention solves these conventional drawbacks, and provides a branched board made of a substrate cut so that the surface obtained by rotating the X-axis and Y-axis by 45 degrees around the Z-axis becomes a horizontal plane. Combining an interferometric optical waveguide body and a polarization constant optical fiber, the output fluctuation of the light source,
The present invention provides a device that can compensate for changes in the characteristics of the transmission body itself, optical transmission loss, etc. with a simple configuration, is less affected by temperature changes, and can obtain a large output signal.
以下、図面を用いて詳細に説明する。 Hereinafter, it will be explained in detail using the drawings.
第２図は、本発明の一実施例を示すブロツク図
であり、５０はレーザダイオードなどの光源、６
０，７０は定偏波光フアイバー、８０はビームス
プリツタ、９０，１００はフオトトランジスタな
どの受光素子である。 FIG. 2 is a block diagram showing an embodiment of the present invention, in which 50 is a light source such as a laser diode, and 6 is a light source such as a laser diode.
0 and 70 are constant polarization optical fibers, 80 is a beam splitter, and 90 and 100 are light receiving elements such as phototransistors.
分岐干渉形光導波路体は、第１図に示した分岐
干渉形光導波路体と同形状に形成されたものであ
り、第３図に示すようにＺ軸を中心にしてＸ軸及
びＹ軸を45度回転させた面が水平面となるように
カツトされた基板１０上に、光導波路２０が単一
モード伝送体として形成されたものを用いる。定
偏波光フアイバー６０，７０は光の偏波面を保存
して伝送できるものであり、第４図に示すよう
に、円形のコアＡ、このコアＡを中心とする楕円
形の第１クラツドＢ及び円形の第２クラツドＣと
で構成されている。分岐干渉形光導波路体の光導
波路２０に光源５０の出力光を伝送する第１の定
偏波光フアイバー６０は、第５図に示すように、
楕円クラツドＢの長軸が分岐干渉形光導波路体の
基板１０の水平軸に対して45度の角度で交わるよ
うにして光導波路２０の入力部に接続されてい
る。一方、分岐干渉形光導波路体で強度変調され
た光を伝送する第２の定偏波光フアイバー７０
は、第６図に示すように、楕円クラツドＢの長軸
が分岐干渉形光導波路体の基板１０の水平軸と平
行になるようにして光導波路２０の出力部に接続
されている。 The branching interference type optical waveguide body is formed in the same shape as the branching interference type optical waveguide body shown in Fig. 1, and as shown in Fig. 3, the X-axis and Y-axis are An optical waveguide 20 is formed as a single mode transmission body on a substrate 10 which is cut so that the surface rotated by 45 degrees becomes a horizontal plane. The constant polarization optical fibers 60 and 70 are capable of transmitting light while preserving the plane of polarization, and as shown in FIG. It is composed of a circular second cladding C. As shown in FIG. 5, the first polarized optical fiber 60 that transmits the output light from the light source 50 to the optical waveguide 20 of the branching interference type optical waveguide body is
The elliptical cladding B is connected to the input portion of the optical waveguide 20 so that its long axis intersects the horizontal axis of the substrate 10 of the branching interference type optical waveguide body at an angle of 45 degrees. On the other hand, a second polarization-controlled optical fiber 70 transmits intensity-modulated light using a branching interference type optical waveguide body.
As shown in FIG. 6, the elliptical cladding B is connected to the output part of the optical waveguide 20 so that its long axis is parallel to the horizontal axis of the substrate 10 of the branching interference type optical waveguide body.
このような構成において、定偏波光フアイバー
は前述のように光の偏波面を保存して伝送できる
ので、第１の定偏波光フアイバー６０を介して光
源５０の直線偏波出力光が分岐干渉形光導波路体
の光導波路２０の入力部に加えられると、光導波
路２０には基板１０の水平軸方向に沿つた偏波面
を有するTE波と基板１０の垂直軸方向に沿つた
偏波面を有するTM波とが発生する。また、光導
波路２０は前述のように単一モード伝送体として
形成されているので、両波は互いに干渉すること
なく独立して伝送される。このような光導波路２
０の屈折率が電気光学効果により変化すると、
TM波及びTE波の速度はそれぞれの方向に関連
した屈折率変化に応じて変化する。ここで、基板
１０の水平方向に電界Ｅを加えるとすると、基板
１０として従来のようにＸ、Ｚ軸が水平面となり
Ｙ軸が垂直面となるようにカツトされたものを用
いた場合には電界は結晶軸のＸ軸方向には大きく
作用してＹ軸方向には小さく作用することから
TE波に関連した方向の屈折率の変化は大きくな
りTM波に関連した方向の屈折率の変化は小さく
なるが、本発明のようにＺ軸を中心にしてＸ軸お
よびＹ軸を45度回転させた面が水平面となるよう
にカツトされたものを用いる場合には電界は結晶
軸のＸ軸方向とＹ軸方向に等しく作用することか
らTM波に関連した方向の屈折率の変化は＋ｋ・
r22・Ｅとなり、TE波に関連した方向の屈折率の
変化は−ｋ・r22・Ｅとなる。なお、r22は電気光
学係数、ｋはｋ＝2πL／λで表わされる定数であ
り、λは光の波長、Ｌは光路長である。 In such a configuration, since the constant polarization optical fiber can transmit light while preserving the polarization plane as described above, the linearly polarized output light of the light source 50 is transmitted via the first constant polarization optical fiber 60 into a branching interference type. When applied to the input part of the optical waveguide 20 of the optical waveguide body, the optical waveguide 20 receives a TE wave having a polarization plane along the horizontal axis direction of the substrate 10 and a TM wave having a polarization plane along the vertical axis direction of the substrate 10. Waves are generated. Further, since the optical waveguide 20 is formed as a single mode transmitter as described above, both waves are transmitted independently without interfering with each other. Such an optical waveguide 2
When the refractive index of 0 changes due to the electro-optic effect,
The velocities of TM and TE waves vary according to the refractive index changes associated with their respective directions. Here, if we apply an electric field E in the horizontal direction of the substrate 10, if we use a conventional substrate 10 cut so that the X and Z axes are horizontal planes and the Y axis is a vertical plane, the electric field E will be This is because it acts strongly in the X-axis direction of the crystal axis and acts small in the Y-axis direction.
The change in the refractive index in the direction related to the TE wave is large, and the change in the refractive index in the direction related to the TM wave is small, but if the X and Y axes are rotated by 45 degrees around the Z axis as in the present invention, When using a crystal cut so that the horizontal plane is used, the electric field acts equally in the X-axis and Y-axis directions of the crystal axis, so the change in refractive index in the direction related to the TM wave is +k・
r 22 ·E, and the change in refractive index in the direction related to the TE wave is -k · r 22 ·E. Note that r 22 is an electro-optic coefficient, k is a constant expressed by k=2πL/λ, λ is the wavelength of light, and L is the optical path length.
一方、ビームスプリツタ８０には定偏波光フア
イバー７０を介してTM、TE両波が独立して伝
送される。ビームスプリツタ８０はTM、TE両
波をそれぞれ分離し、TM波を受光素子９０に伝
送してTE波を受光素子１００に伝送する。ここ
で、ビームスプリツタ８０に伝送される光の大き
さをI0とし、λ／４のバイアスが与えられている
ものとすると、受光素子９０の出力信号I1は、
I1＝I0｛１＋sin（＋ｋ・r22・Ｅ）｝／２ (1)
となり、受光素子１００の出力信号I2は、
I2＝I0｛１＋sin（−ｋ・r22・Ｅ）｝／２ (2)
となる。従つて、これらI1とI2との比をとること
により、
I1／I2＝｛１＋sin（＋ｋ・r22・Ｅ）｝
／｛１＋sin（−ｋ・r22・Ｅ）｝
≒（１＋ｋ・r22・Ｅ）／（１−ｋ・r22・Ｅ）
≒１＋２・ｋ・r22・Ｅ (3)
となり、光伝送時の損失、伝送体自体の特性変
化、光源の出力光の変動などにより変化するI0の
影響を打ち消すことができ、比較的大きな出力信
号を得ることができる。また、光をＺ軸方向に通
過させているので温度変化の影響を極めて小さく
することができる。 On the other hand, both the TM and TE waves are independently transmitted to the beam splitter 80 via the constant polarization optical fiber 70. The beam splitter 80 separates both the TM and TE waves, and transmits the TM wave to the light receiving element 90 and the TE wave to the light receiving element 100. Here, if the magnitude of the light transmitted to the beam splitter 80 is I 0 and a bias of λ/4 is given, the output signal I 1 of the light receiving element 90 is I 1 =I 0 { 1+sin(+k・r 22・E)}/2 (1), and the output signal I 2 of the light receiving element 100 is I 2 =I 0 {1+sin(−k・r 22・E)}/2 (2) Become. Therefore, by taking the ratio of I 1 and I 2 , I 1 /I 2 = {1+sin (+k・r 22・E)} / {1+sin (−k・r 22・E)} ≒ (1+k・r 22・E)/(1−k・r 22・E) ≒1+2・k・r 22・E (3) Therefore, loss during optical transmission, changes in the characteristics of the transmission body itself, and fluctuations in the output light of the light source It is possible to cancel the influence of I 0 that changes due to etc., and it is possible to obtain a relatively large output signal. Furthermore, since the light is transmitted in the Z-axis direction, the influence of temperature changes can be extremely minimized.
なお、必要に応じて、次のような信号処理を行
うこともできる。すなわち、受光素子９０の出力
信号I1と受光素子９０の出力信号I2との和をとる
と、
I1＋I2＝I0 (4)
となり、これらの差をとると、
I1−I2＝I0・sin（ｋ・r22・Ｅ） (5)
となる。従つて、これら和と差の比をとると、
I1−I2／I1＋I2＝sin（ｋ・r22・Ｅ） (6)
となつて、前述(3)式と同様なI0と無関係な出力を
得ることができる。 Note that the following signal processing can also be performed as necessary. That is, the sum of the output signal I 1 of the light receiving element 90 and the output signal I 2 of the light receiving element 90 is I 1 +I 2 =I 0 (4), and the difference between them is I 1 −I 2 =I 0・sin(k・r 22・E) (5) Therefore, if we take the ratio of these sums and differences, we get I 1 - I 2 /I 1 + I 2 = sin (k・r 22・E) (6), which is I 0 similar to equation (3) above. You can get unrelated output.
このような構成によれば、例えば信号源の出力
信号の大きさを電気的に完全に絶縁した状態で測
定できる光電圧計が実現できるのをはじめ、光通
信システムにおける各種の光信号処理装置に用い
ることができる。すなわち、TM波とTE波は符
号の異なる相補的な信号となるので、デジタルデ
ータ伝送時におけるビツトエラーチエツクを簡単
に行うことができる。 According to such a configuration, for example, it is possible to realize an optical voltmeter that can measure the magnitude of the output signal of a signal source in a completely electrically isolated state, and it can also be used in various optical signal processing devices in optical communication systems. be able to. That is, since the TM wave and the TE wave are complementary signals with different signs, it is possible to easily check bit errors during digital data transmission.
また、必要に応じて、光源５０にフイードバツ
クをかけることもできる。この場合には、(4)式で
表わされる受光素子９０の出力信号I1と受光素子
１００の出力信号I2との和の信号を用いればよ
く、これにより、印加電界Ｅとは無関係に光源５
０にフイードバツクをかけることができる。 Additionally, feedback can be applied to the light source 50 if necessary. In this case, it is sufficient to use a signal that is the sum of the output signal I 1 of the light receiving element 90 and the output signal I 2 of the light receiving element 100 expressed by equation (4). 5
You can apply feedback to 0.
なお、ビームスプリツタに入力される光にλ／
４のバイアス位相を与えるのにあたつては、分岐
干渉形光導波路体の光導波路２０に電気的なバイ
アスを加えてもよいし、光導波路２０の位相推移
部２２のパターンに光路差を与えるようにしても
よい。 Note that the light input to the beam splitter has λ/
In order to provide the bias phase of 4, an electrical bias may be applied to the optical waveguide 20 of the branching interference type optical waveguide body, or an optical path difference may be applied to the pattern of the phase shift portion 22 of the optical waveguide 20. You can do it like this.
また、基板としては、タンタル酸リチウム
（LiTaO0）で構成されたものを用いてもよい。 Furthermore, the substrate may be made of lithium tantalate (LiTaO 0 ).
これらから明らかなように、本発明によれば、
光源の出力変動、伝送体自体の特性変化、光の伝
送損失などを簡単な構成で補償でき、さらに、温
度変化の影響が小さく、大きな出力信号を得るこ
とができる光変調装置が実現でき、実用上の効果
は大きい。 As is clear from these, according to the present invention,
We have created an optical modulation device that can compensate for variations in the output of the light source, changes in the characteristics of the transmitter itself, and optical transmission losses with a simple configuration, and that is less affected by temperature changes and can obtain a large output signal, making it suitable for practical use. The above effect is significant.
第１図は分岐干渉形光導波路体の一例を示す構
成説明図、第２図は本発明の一実施例を示すブロ
ツク図、第３図は本発明で用いる分岐干渉形光導
波路体の基板の結晶方位を示す説明図、第４図は
本発明で用いる定偏波光フアイバーの断面図、第
５図は本発明における分岐干渉形光導波路体の入
力部での定偏波光フアイバーの接続説明図、第６
図はその出力部での定偏波光フアイバーの接続説
明図である。
１０……基板、２０……光導波路、３０……電
極、４０……信号源、５０……光源、６０，７０
……定偏波光フアイバー、８０……ビームスプリ
ツタ、９０，１００……受光素子。
Fig. 1 is a configuration explanatory diagram showing an example of a branching interference type optical waveguide body, Fig. 2 is a block diagram showing an embodiment of the present invention, and Fig. 3 is a diagram showing a substrate of the branching interference type optical waveguide body used in the present invention. An explanatory diagram showing the crystal orientation, FIG. 4 is a cross-sectional view of the polarization-controlled optical fiber used in the present invention, and FIG. 5 is an explanatory diagram of the connection of the polarization-controlled optical fiber at the input part of the branching interference type optical waveguide body in the present invention. 6th
The figure is an explanatory diagram of the connection of the constant polarization optical fiber at the output section. DESCRIPTION OF SYMBOLS 10... Substrate, 20... Optical waveguide, 30... Electrode, 40... Signal source, 50... Light source, 60, 70
. . . Constant polarization optical fiber, 80 . . . Beam splitter, 90, 100 . . . Light receiving element.
Claims (1)
せた面が水平面となるようにカツトされた基板上
に光導波路が単一モード伝送体として形成された
分岐干渉形光導波路体と、楕円クラツドの長軸が
分岐干渉形光導波路体の水平軸に対して45度の角
度で交わるようにして分岐干渉形光導波路体の入
力部に接続され分岐干渉形光導波路体に光を伝送
する第１の定偏波光フアイバーと、分岐干渉形光
導波路体を通過する光に電界を印加して強度変調
するように分岐干渉形光導波路体に形成された電
極と、楕円クラツドの長軸が分岐干渉形光導波路
体の水平軸と平行になるようにして分岐干渉形光
導波路体の出力部に接続され強度変調された光を
伝送する第２の定偏波光フアイバーとで構成され
たことを特徴とする光変調装置。1. A branching interference type optical waveguide body in which an optical waveguide is formed as a single mode transmission body on a substrate cut so that the surface obtained by rotating the X-axis and Y-axis by 45 degrees around the Z-axis becomes a horizontal plane. , the long axis of the elliptical cladding intersects the horizontal axis of the branching interference type optical waveguide body at an angle of 45 degrees, and is connected to the input part of the branching interference type optical waveguide body, and light is transmitted to the branching interference type optical waveguide body. a first constant polarization optical fiber, an electrode formed on the branching interference type optical waveguide body so as to apply an electric field to the light passing through the branching interference type optical waveguide body to modulate the intensity, and a long axis of the elliptical cladding. A second constant polarization optical fiber is connected to the output part of the branched interference type optical waveguide body in parallel with the horizontal axis of the branched interference type optical waveguide body and transmits intensity-modulated light. Characteristic light modulation device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7124083A JPS59197012A (en) | 1983-04-22 | 1983-04-22 | Optical modulator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7124083A JPS59197012A (en) | 1983-04-22 | 1983-04-22 | Optical modulator |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS59197012A JPS59197012A (en) | 1984-11-08 |
| JPS6412367B2 true JPS6412367B2 (en) | 1989-02-28 |
Family
ID=13454972
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP7124083A Granted JPS59197012A (en) | 1983-04-22 | 1983-04-22 | Optical modulator |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS59197012A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07120631A (en) * | 1993-09-06 | 1995-05-12 | Ngk Insulators Ltd | Optical waveguide type part |
| JP4823584B2 (en) | 2005-06-22 | 2011-11-24 | 富士通オプティカルコンポーネンツ株式会社 | Light modulator |
-
1983
- 1983-04-22 JP JP7124083A patent/JPS59197012A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS59197012A (en) | 1984-11-08 |
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