JPH0426085B2 - - Google Patents
Info
- Publication number
- JPH0426085B2 JPH0426085B2 JP16697383A JP16697383A JPH0426085B2 JP H0426085 B2 JPH0426085 B2 JP H0426085B2 JP 16697383 A JP16697383 A JP 16697383A JP 16697383 A JP16697383 A JP 16697383A JP H0426085 B2 JPH0426085 B2 JP H0426085B2
- Authority
- JP
- Japan
- Prior art keywords
- optical waveguide
- optical
- conversion element
- length
- wavelength conversion
- 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 - Lifetime
Links
- 230000003287 optical effect Effects 0.000 claims description 71
- 238000006243 chemical reaction Methods 0.000 claims description 32
- 229910013641 LiNbO 3 Inorganic materials 0.000 claims description 15
- 239000013078 crystal Substances 0.000 claims description 9
- 230000008878 coupling Effects 0.000 claims description 2
- 238000010168 coupling process Methods 0.000 claims description 2
- 238000005859 coupling reaction Methods 0.000 claims description 2
- 239000004065 semiconductor Substances 0.000 description 10
- 238000005452 bending Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000003321 amplification Effects 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 230000010365 information processing Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 239000000758 substrate Substances 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
- G02F1/35—Non-linear optics
- G02F1/37—Non-linear optics for second-harmonic generation
- G02F1/377—Non-linear optics for second-harmonic generation in an optical waveguide structure
Landscapes
- Physics & Mathematics (AREA)
- Nonlinear Science (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Optical Integrated Circuits (AREA)
- Liquid Crystal (AREA)
Description
【発明の詳細な説明】
産業上の利用分野
本発明は、レーザ光を使用する情報処理分野あ
るいは光応用計測制御分野に利用する光波長変換
素子に関するものである。DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an optical wavelength conversion element used in the information processing field or optical applied measurement control field using laser light.
従来例の構造とその問題点
従来、0.7μm以下の短波長領域においては半導
体レーザによる発振が困難であるため、気体レー
ザなどの大型レーザが使われており、大型化がさ
けられなかつた。そのためSHG（第２高調波発
生）現象を利用し半導体レーザ光を半分の波長に
変換する素子が作製されていた。第１図は従来の
LiNbO3光導波路を使用した光波長変換素子によ
り半導体レーザ光を変換する構成を示した斜視図
である。半導体レーーザ１から出た波長λの光は
レンズ２により集光されてLiNbO3Y板３に形成
された光導波路４に入る。この波長λの半導体レ
ーザよりの入射光を変換された波長λ／２の光の
位相整合条件をLiNbO3光導波路４の温度を変え
るなどの方法により満たしてやることにより数パ
ーセントの変換効率で波長λ／２の変換光を得て
いた。実際にLiNNbO3Y板３に幅6μm，深さ
1.5μm長さ２cmのTi拡散光導波路４を作製し、波
長1.3μm，出力40mWの半導体レーザの光を光導
波路４に入射することにより、２％の変換効率で
波長0.65μmの変換光が得られている。しかし、
変換効率は光導波路４アスペクト比（幅と深さの
比）が１に近い程良く、LiNbO3Y板３ではＺ軸
方向の拡散係数が大きいために、光導波路４が大
きく横に広がつてしまい変換率が極端に悪くな
る。また変換効率は光導波路４の長さの二乗に比
例するのであるが、変換効率を上げようとした場
合、Ｘ軸方向のLiNbO3Y板３の長さを長くとら
なければならず、光波長変換素子の大きさが大き
くなつてしまう。Conventional structures and their problems Conventionally, it has been difficult to oscillate with semiconductor lasers in the short wavelength region of 0.7 μm or less, so large lasers such as gas lasers have been used, and larger lasers have been unavoidable. For this reason, elements have been created that utilize the SHG (second harmonic generation) phenomenon to convert semiconductor laser light into half the wavelength. Figure 1 shows the conventional
FIG. 2 is a perspective view showing a configuration in which semiconductor laser light is converted by an optical wavelength conversion element using a LiNbO 3 optical waveguide. Light with wavelength λ emitted from semiconductor laser 1 is focused by lens 2 and enters optical waveguide 4 formed in LiNbO 3 Y plate 3 . By satisfying the phase matching condition for the converted light of wavelength λ/2 from the incident light from the semiconductor laser of wavelength λ by changing the temperature of the LiNbO 3 optical waveguide 4, the wavelength λ can be converted with a conversion efficiency of several percent. /2 converted light was obtained. Actually, LiNNbO 3 Y plate 3 has a width of 6 μm and a depth of
By fabricating a Ti diffused optical waveguide 4 with a length of 1.5 μm and 2 cm, and inputting light from a semiconductor laser with a wavelength of 1.3 μm and an output of 40 mW into the optical waveguide 4, converted light with a wavelength of 0.65 μm was obtained with a conversion efficiency of 2%. It is being but,
The conversion efficiency is better when the aspect ratio (width to depth ratio) of the optical waveguide 4 is close to 1, and because the LiNbO 3 Y plate 3 has a large diffusion coefficient in the Z-axis direction, the optical waveguide 4 spreads widely laterally. As a result, the conversion rate becomes extremely poor. Furthermore, the conversion efficiency is proportional to the square of the length of the optical waveguide 4, but in order to increase the conversion efficiency, it is necessary to increase the length of the LiNbO 3 Y plate 3 in the X-axis direction, which increases the optical wavelength. The size of the conversion element becomes large.
発明の目的
本発明の目的は、Ｘ，Ｙ，Ｚ各軸を有する非線
形光学結晶のＺ板を用いることにより、Ｚ面に形
成された光導波路のアスペクト比を１に近付け、
さらに上記光導波路路を折り返しまた曲り構造に
して光導波路の長さをかせぐことによりり、従来
では困難であつた変換効率を大きく上げるコンパ
クトな光波長変換素子を提供することにある。Purpose of the Invention The purpose of the present invention is to bring the aspect ratio of the optical waveguide formed on the Z plane close to 1 by using a Z plate of a nonlinear optical crystal having each of the X, Y, and Z axes.
Furthermore, it is an object of the present invention to provide a compact optical wavelength conversion element that greatly increases the conversion efficiency, which has been difficult in the past, by increasing the length of the optical waveguide by folding or bending the optical waveguide.
発明の構成
本発明の光波長変換素子は、Ｘ，Ｙ，Ｚ各軸を
有する非線形光学結晶のＺ面に、前記Ｘ，Ｙ軸方
向の長さよりも長い光導波路を設けた構成であ
る。また本発明の光波長変換素子は上記非線光学
結晶としてLiNbO3Z板，LiTaO3Z板を用いた構
成である。また本発明の光波長変換素子は上記光
導波路として全反射または方向性結合による折り
返し光導波路、または曲り光導波路を用いた構成
である。Configuration of the Invention The optical wavelength conversion element of the present invention has a configuration in which an optical waveguide longer than the length in the X and Y axis directions is provided on the Z plane of a nonlinear optical crystal having each of the X, Y, and Z axes. Further, the optical wavelength conversion element of the present invention has a structure using a LiNbO 3 Z plate and a LiTaO 3 Z plate as the non-linear optical crystal. Further, the optical wavelength conversion element of the present invention has a configuration in which a folded optical waveguide by total reflection or directional coupling, or a curved optical waveguide is used as the optical waveguide.
実施例の説明
第２図は、本発明よる光波長変換素子の第１の
実施例の構成を示した斜視図である。第２図にお
いて、Ｘ軸方向に２cm，Ｙ軸方向に１cmの長さを
持つたLiNbO3Z板３′のＺ面にTiを熱拡散するこ
とにより幅6μm，深さ4μmの光導波路４ａを形成
した。この光導波路４ａに入射端部５より波長λ
の光が入射され、この光は金属膜が蒸着された反
射端部６で反射され、次の光導波路４ｂに移る。
光導波路ａと光導波路ｂは3゜の角度をもたせてあ
る。同様の過程を経て光導波路４ｃに入つた光は
出射端部７よ出射する。全光導波路の長さはほぼ
６cmとなる。DESCRIPTION OF EMBODIMENTS FIG. 2 is a perspective view showing the structure of a first embodiment of the optical wavelength conversion element according to the present invention. In Fig. 2, an optical waveguide 4a with a width of 6 μm and a depth of 4 μm is formed by thermally diffusing Ti on the Z plane of a LiNbO 3 Z plate 3' having a length of 2 cm in the X-axis direction and 1 cm in the Y-axis direction. Formed. The wavelength λ from the input end 5 to this optical waveguide 4a
This light is reflected by the reflective end 6 on which a metal film is deposited, and moves to the next optical waveguide 4b.
The optical waveguide a and the optical waveguide b are at an angle of 3°. The light that has entered the optical waveguide 4c through a similar process is output from the output end 7. The length of the entire optical waveguide is approximately 6 cm.
ここで波長λの入射光の光と波長λ／２変換波
の光との位相を温度などにより整合させることに
より、変換波の出力パワーを最大にすることがで
きる。実際には波長1.3μm，出力パワー40mWの
半導体レーザをレンズで集光して入射端部５より
入射させ、温度より位相を整合させることで20％
強の変換効率が得られた。 Here, the output power of the converted wave can be maximized by matching the phases of the incident light having the wavelength λ and the wavelength λ/2 converted wave using temperature or the like. In reality, a semiconductor laser with a wavelength of 1.3 μm and an output power of 40 mW is focused by a lens and made incident from the input end 5, and the phase is matched by temperature to achieve a 20%
Strong conversion efficiency was obtained.
第３図は、本発明による光波長変換素子の第２
の実施例を示した斜視図である。LiNbO3Z板
３′に設けられた光導波路４ａと４ｂ，４ｂと４
ｃ間の結合は完全結合長を持つた方向性結合によ
つて行つてる以外は実施例１と同様である。 FIG. 3 shows a second optical wavelength conversion element according to the present invention.
FIG. 2 is a perspective view showing an embodiment of the invention. Optical waveguides 4a and 4b, 4b and 4 provided on LiNbO 3 Z plate 3'
The bonding between c and c is the same as in Example 1 except that the bonding is performed by directional bonding having a complete bond length.
第４図は、本発明よる光波長変換素子の第３の
実施例を示した斜視図である。この実施例では折
り返し導波路を用いる代りに、曲り光導波路とし
て渦巻き光導波路４を用いて波長変換素子を構成
した。LiNbO3Y板では曲りを付けることにより
伝搬定数が変化し位相整合条件が各場所により異
なるが、LiNbO3Z板を用いているため伝搬定数
は変化しないいので位相整合条件は場所により異
ならない。光導波路４は全長５cmである。この光
導波路４′に波長0.8μm，出力パワー30mWの半
導体レーザ光を入射させ、温度により位相を整合
させたところ15％の変換効率で波長0.4μmの変換
光が得られた。 FIG. 4 is a perspective view showing a third embodiment of the optical wavelength conversion element according to the present invention. In this embodiment, instead of using a folded waveguide, a spiral optical waveguide 4 was used as a curved optical waveguide to construct a wavelength conversion element. When bending a LiNbO 3 Y plate, the propagation constant changes and the phase matching conditions differ depending on the location, but since the LiNbO 3 Z plate is used, the propagation constant does not change, so the phase matching conditions do not differ depending on the location. The optical waveguide 4 has a total length of 5 cm. When a semiconductor laser beam with a wavelength of 0.8 μm and an output power of 30 mW was introduced into this optical waveguide 4' and the phase was matched by temperature, converted light with a wavelength of 0.4 μm was obtained with a conversion efficiency of 15%.
以上実施例では結晶としてLiNbO3Z板を用い
たが他にLiTaO3などＸ，Ｙ，Ｚ軸を持つ非線形
光学結晶であればよい。また、実施例ではＸ軸方
向の前記非線形光学結晶の長さの数倍の長さを持
つ光導波路を用いたが、折り返す回数を増すなど
によりさらに光導波路長を長くして変換効率をさ
らにあげることも可能である。また曲り光導波路
として渦巻き光導波路を用いて説明を行つたが、
Ｕ字型，Ｓ字型などこれに限ることはない。また
本実施例ではSHGについて説明を行つたが、光
パラメトリツク増幅，和周波，差周波などにも用
いることができる。 In the above embodiments, a LiNbO 3 Z plate was used as the crystal, but any other nonlinear optical crystal having X, Y, and Z axes such as LiTaO 3 may be used. In addition, in the example, an optical waveguide having a length several times the length of the nonlinear optical crystal in the X-axis direction was used, but the conversion efficiency can be further increased by increasing the optical waveguide length by increasing the number of turns. It is also possible. Also, although the explanation was given using a spiral optical waveguide as a curved optical waveguide,
The shape is not limited to U-shape, S-shape, etc. Further, in this embodiment, the SHG has been explained, but it can also be used for optical parametric amplification, sum frequency, difference frequency, etc.
発明の効果
以上説明したように、本発明の光波長変換素子
においては、Ｘ，Ｙ，Ｚ各軸を有する非線形光学
結晶のＺ面に前記Ｘ，Ｙ軸方向の基板の長さより
長い光導波路を作製することにより、従来のＸ，
Ｙ面に作製された光導波路に比べSHG変換効率
を十数倍程度高めることができるすぐれた効果を
発揮することができる。Effects of the Invention As explained above, in the optical wavelength conversion element of the present invention, an optical waveguide longer than the length of the substrate in the X, Y axis directions is provided on the Z plane of the nonlinear optical crystal having each of the X, Y, and Z axes. By making the conventional X,
It can exhibit an excellent effect of increasing the SHG conversion efficiency by more than ten times compared to an optical waveguide fabricated in the Y plane.
第１図は従来のLiNbO3光導波路を使用した光
波長変換素子により半導体レーザ光を変換する装
置の概略斜視図、第２図は本発明による光波長変
換素子の第１の実施例の構成を示した概略斜視
図、第３図は本発明による光波長変換素子による
第２の実施例を示した概略斜視図、第４図は本発
明による光波長変換素子の第３の実施例を示した
概略斜視図である。
１……半導体レーザ、２……レンズ、３……
LiNbO3Y板、４ａ，４ｂ，４ｃ，４′……光導波
路、３′……LiNbO3Z板、５……入射端部、６…
…反射端部、７……出射端部。
Fig. 1 is a schematic perspective view of a device for converting semiconductor laser light by an optical wavelength conversion element using a conventional LiNbO 3 optical waveguide, and Fig. 2 shows the configuration of a first embodiment of the optical wavelength conversion element according to the present invention. 3 is a schematic perspective view showing a second embodiment of the optical wavelength conversion element according to the present invention, and FIG. 4 is a schematic perspective view showing a third embodiment of the optical wavelength conversion element according to the present invention. It is a schematic perspective view. 1... Semiconductor laser, 2... Lens, 3...
LiNbO 3 Y plate, 4a, 4b, 4c, 4'... optical waveguide, 3'... LiNbO 3 Z plate, 5... incident end, 6...
...Reflection end, 7...Emission end.
Claims (1)
面に前記Ｘ，Ｙ軸方向の長さよりも長い光導波路
を設けたことを特徴とする光波長変換素子。 ２ Ｘ，Ｙ，Ｚ各軸を有する非線形半学結晶とし
てLiNbO3Z板又はLiTaO3Z板を用いたことを特
徴とする特許請求の範囲第１項記載の光波長変換
素子。 ３ Ｘ，Ｙ軸方向の長さよりも長い光導波路とし
て折り返し光導波路を設けたことを特徴とする特
許請求の範囲第１項記載の光波長変換素子。 ４ Ｘ，Ｙ軸方向の長さよりも長い光導波路とし
て、方向性結合による折り返し光導波路を設けた
ことを特徴とする特許請求の範囲第１項記載の光
波長変換素子。 ５ Ｘ，Ｙ軸方向の長さよりも長い光導波路とし
て、曲り光導波路を設けたことを特徴とする特許
請求の範囲第１項記載の光波長変換素子。[Claims] 1. Z of a nonlinear optical crystal having X, Y, and Z axes
An optical wavelength conversion element characterized in that an optical waveguide having a length longer than the length in the X and Y axis directions is provided on the surface. 2. The optical wavelength conversion element according to claim 1, characterized in that a LiNbO 3 Z plate or a LiTaO 3 Z plate is used as the nonlinear semimagnetic crystal having X, Y, and Z axes. 3. The optical wavelength conversion element according to claim 1, characterized in that a folded optical waveguide is provided as an optical waveguide that is longer than the length in the X and Y axis directions. 4. The optical wavelength conversion element according to claim 1, characterized in that a folded optical waveguide by directional coupling is provided as the optical waveguide which is longer than the length in the X and Y axis directions. 5. The optical wavelength conversion element according to claim 1, characterized in that a curved optical waveguide is provided as the optical waveguide which is longer than the length in the X and Y axis directions.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16697383A JPS6057825A (en) | 1983-09-09 | 1983-09-09 | Light wavelength converting element |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16697383A JPS6057825A (en) | 1983-09-09 | 1983-09-09 | Light wavelength converting element |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6057825A JPS6057825A (en) | 1985-04-03 |
| JPH0426085B2 true JPH0426085B2 (en) | 1992-05-06 |
Family
ID=15841045
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP16697383A Granted JPS6057825A (en) | 1983-09-09 | 1983-09-09 | Light wavelength converting element |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6057825A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8294979B2 (en) | 2007-11-21 | 2012-10-23 | Panasonic Corporation | Wavelength conversion device and image display apparatus using the same |
-
1983
- 1983-09-09 JP JP16697383A patent/JPS6057825A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6057825A (en) | 1985-04-03 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP2892938B2 (en) | Wavelength converter | |
| US5091915A (en) | Semiconductor laser excited solid laser device | |
| EP0377988B1 (en) | Wavelength converting optical device | |
| JPH04107536A (en) | Second harmonic generation device | |
| US5082340A (en) | Wavelength converting device | |
| JPS6118934A (en) | Device for changing wavelength of light | |
| KR20010092756A (en) | A device for reflecting light | |
| JPH02179626A (en) | Light wavelength converter | |
| JPS60112023A (en) | Light wavelength conversion element | |
| JPS63121829A (en) | Harmonic generating device | |
| JP2751914B2 (en) | Optical waveguide device | |
| JPH0460524A (en) | Light wavelength converter | |
| JPH0426085B2 (en) | ||
| JPH08286160A (en) | Acoustooptic filter | |
| JP5361897B2 (en) | Optical wavelength conversion element, wavelength conversion laser device, and image display device | |
| JPS60112024A (en) | Light wavelength converter | |
| JPH01257922A (en) | Waveguide type wavelength converting element | |
| JP3147412B2 (en) | Incident taper optical waveguide and wavelength conversion element using the same | |
| JPS62124510A (en) | Grating optical coupler | |
| JPS61189686A (en) | Laser device | |
| JPH01312529A (en) | Nonlinear optical element | |
| WO2023017709A1 (en) | Ring resonator | |
| JP2003202606A (en) | Optical switch | |
| JPS6118933A (en) | Device for changing wavelength of light | |
| JP2688102B2 (en) | Optical wavelength converter |