JPH07112095B2 - Ultrashort optical pulse generator - Google Patents
Ultrashort optical pulse generatorInfo
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- JPH07112095B2 JPH07112095B2 JP2135949A JP13594990A JPH07112095B2 JP H07112095 B2 JPH07112095 B2 JP H07112095B2 JP 2135949 A JP2135949 A JP 2135949A JP 13594990 A JP13594990 A JP 13594990A JP H07112095 B2 JPH07112095 B2 JP H07112095B2
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- semiconductor laser
- pulse generator
- resonator
- optical pulse
- ultrashort
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Description
【発明の詳細な説明】 産業上の利用分野 本発明は、光計測、光情報処理、光通信等の光源として
応用される超短光パルス発生装置に関するものである。TECHNICAL FIELD The present invention relates to an ultrashort optical pulse generator applied as a light source for optical measurement, optical information processing, optical communication and the like.
従来の技術 半導体レーザを用いて超短光パルスを発生する方法とし
ては、能動モード同期法、受動モード同期法利得スイッ
チング法等がある。能動および受動モード同期法につい
ては、例えば、セミコンダクターズ アンド セミメタ
ルズ 22巻パートＢチャプター１（Semiconductors and
Semimetals,vol.22,part B,Chapter 1）に詳しく解説
されている。能動モード同期は半導体レーザへの注入電
流を外部共振器のラウンドトリップ周波数で変調を行
う。受動モード同期は、共振器内に可飽和吸収体を含む
ことにより行う。いずれの場合も外部共振器のラウンド
トリップ周波数で光パルスが発振し、その光パルスの時
間幅としては１〜20psのものが得られている。利得スイ
ッチング法は、半導体レーザを短い電流パルスで励起
し、レーザ発振の過渡応答として生じる緩和振動の最初
のパルスだけを取り出して短パルス光を発生させる方法
である。この方法では、繰り返し周波数を自由に設定す
ることができる。また、半導体レーザを用いた波長変換
型超短光パルスの発生については、谷内、山本「SHGを
用いた青色レーザ光源によるピコ秒発生」第49回応用物
理学会学術講演予稿集7a-ZD-8に報告されている。第８
図に、従来の波長変換型超短光パルス発生装置の概略構
成図を示す。１は半導体レーザ、２は波長変換素子であ
り、３は光導波路、4,5はレンズ、６はλ/2板である。
半導体レーザ１から出射されたTEモード発振の基本波７
は、レンズ４でコリメートされ、λ/2板６で偏光方向を
90°変換された後レンズ５で集光されて波長変換素子２
に形成された光導波路に入射する。この際、光導波路３
の中を導波する基本波とチェレンコフ放射される第二高
調波８の位相速度が等しくなり、効率良く第二高調が発
生する。波長0.84μｍの半導体レーザをコムジェネレー
タを用いてパルス幅数百psの短電流パルスで利得スイッ
チすることにより、パルス幅20ps程度の基本波を発生さ
せ、パルス幅10ps程度の波長0.42μｍの第二高調波が得
られている。2. Description of the Related Art As a method of generating an ultrashort optical pulse using a semiconductor laser, there are an active mode locking method, a passive mode locking method and a gain switching method. For active and passive mode-locking methods, see, for example, Semiconductors and Semiconductors, Volume 22, Part B Chapter 1 (Semiconductors and
Semimetals, vol.22, part B, Chapter 1). Active mode locking modulates the injection current to the semiconductor laser with the round-trip frequency of the external cavity. Passive mode-locking is performed by including a saturable absorber in the resonator. In either case, the optical pulse oscillates at the round trip frequency of the external resonator, and the time width of the optical pulse is 1 to 20 ps. The gain switching method is a method in which a semiconductor laser is excited by a short current pulse and only the first pulse of relaxation oscillation generated as a transient response of laser oscillation is extracted to generate short pulse light. With this method, the repetition frequency can be set freely. Regarding the generation of wavelength-converted ultrashort optical pulses using a semiconductor laser, Taniuchi and Yamamoto "Picosecond generation with a blue laser light source using SHG" Proceedings of the 49th Japan Society of Applied Physics 7a-ZD-8 Has been reported to. 8th
FIG. 1 shows a schematic configuration diagram of a conventional wavelength conversion type ultrashort optical pulse generator. 1 is a semiconductor laser, 2 is a wavelength conversion element, 3 is an optical waveguide, 4 and 5 are lenses, and 6 is a λ / 2 plate.
TE mode oscillation fundamental wave 7 emitted from the semiconductor laser 1
Is collimated by the lens 4 and the polarization direction is changed by the λ / 2 plate 6.
After 90 ° conversion, the light is condensed by the lens 5 and the wavelength conversion element 2
It is incident on the optical waveguide formed in. At this time, the optical waveguide 3
The phase velocities of the fundamental wave guided in and the second harmonic 8 radiated by Cherenkov are equalized, and the second harmonic is efficiently generated. A semiconductor laser with a wavelength of 0.84 μm is gain-switched with a short current pulse with a pulse width of several hundred ps using a comb generator to generate a fundamental wave with a pulse width of about 20 ps, and a second pulse with a wavelength of 0.42 μm with a pulse width of about 10 ps. Harmonics are obtained.
発明が解決しようとする課題 上記従来の技術で述べたように、半導体レーザの能動お
よび受動モード同期法では、半導体レーザの出射光を外
部共振器で再び半導体レーザに帰還してしまうため、出
力を大きくとることができないという問題点があった。
また、装置の構成が複雑で、調整が困難であった。半導
体レーザの利得スイッチング法では簡単な構成で超短光
パルスの発生が可能であるが、その出力を波長変換した
場合には、現状得られている第二高調波の出力は小さい
ため、半導体レーザの出射光パルスの高出力化が課題と
なっている。半導体レーザの出射光パルスは、励起する
電流パルスのピークを高くすれば大きくなるが、パルス
幅が数百psと小さい場合には、高ピークの電流パルスを
得るのは困難であった。本発明は、上述の問題点に鑑み
てなされたもので、半導体レーザを利得スイッチングす
る短電流パルスのピークを高くすることなく、半導体レ
ーザから出射される光パルスを高出力化することがで
き、その出射光パルスを波長変換して得られる第二高調
波の光パルスも高出力化することができる超短光パルス
発生装置を提供することを目的とする。DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention As described in the above-mentioned conventional technique, in the active and passive mode-locking method of the semiconductor laser, the output light of the semiconductor laser is fed back to the semiconductor laser again by the external resonator, and therefore the output There was a problem that it could not be taken large.
Further, the structure of the device is complicated and adjustment is difficult. With the gain switching method of a semiconductor laser, it is possible to generate an ultrashort optical pulse with a simple configuration, but when the output is wavelength-converted, the currently obtained second harmonic output is small, so the semiconductor laser The issue is to increase the output power of the emitted light pulse. The emission light pulse of the semiconductor laser increases as the peak of the exciting current pulse increases, but when the pulse width is as small as several hundreds ps, it is difficult to obtain a high-peak current pulse. The present invention has been made in view of the above problems, and it is possible to increase the output power of an optical pulse emitted from a semiconductor laser without increasing the peak of a short current pulse for gain switching the semiconductor laser. It is an object of the present invention to provide an ultrashort optical pulse generator capable of increasing the output of a second harmonic optical pulse obtained by wavelength-converting the emitted optical pulse.
課題を解決するための手段 本発明の超短光パルス発生装置は、上述の課題を解決す
るため、半導体基板上に形成された少なくとも活性層及
び閉じ込め層を含む共振器を備え、前記共振器の一部が
前記活性層に電流を注入するための電極を有する利得領
域であり、前記共振器の他部が可飽和吸収領域である半
導体レーザを短電流パルスで励起して利得スイッチング
する構成、あるいは前記構成の超短光パルス発生装置に
おいて、半導体レーザと光導波路構造を有する波長変換
素子が光学的に結合した構造を備え、前記半導体レーザ
から出射される超短パルス光を基本波として前記波長変
換素子に結合し、前記波長変換素子からの出力光として
前記基本波の第二高調波を発生する構成を備えたもので
あり、半導体レーザの共振器の第１の端面が高反射膜を
有し、第２の端面が反射防止膜を有する出射端であって
もよく、また、半導体レーザの可飽和吸収領域が制御電
極を有し、前記可飽和吸収領域と利得領域が電気的に絶
縁された構成であってもよい。Means for Solving the Problems In order to solve the above-mentioned problems, an ultrashort optical pulse generator according to the present invention includes a resonator including at least an active layer and a confinement layer formed on a semiconductor substrate. A configuration in which a gain region having an electrode for injecting a current into the active layer, a part of which is the saturable absorption region in the other part of the resonator, is excited by a short current pulse to perform gain switching, or In the ultrashort optical pulse generator having the above structure, a wavelength conversion element having a semiconductor laser and a wavelength conversion element having an optical waveguide structure is optically coupled, and the wavelength conversion is performed by using the ultrashort pulse light emitted from the semiconductor laser as a fundamental wave. The second end of the resonator of the semiconductor laser has a high height and is configured to generate a second harmonic of the fundamental wave as output light from the wavelength conversion element. The emitting end may have a reflection film and the second end face may have an antireflection film. Further, the saturable absorption region of the semiconductor laser may have a control electrode, and the saturable absorption region and the gain region may be electrically connected. The structure may be electrically insulated.
作用 本発明では、半導体レーザは、電流が注入されると利得
領域で発光が生じるが、発光が小さいときは可飽和吸収
領域での吸収が大きく出力光は低レベルであるが、発光
が大きくなると可飽和吸収領域の吸収が飽和しはじめ、
しきい値をこえるとレーザ発振し出力光は高レベル状態
となる。本発明における半導体レーザでは、短電流パル
スで利得スイッチングを行うと、利得領域の利得の増加
と可飽和吸収領域の吸収の低下の相乗効果により、通常
の半導体レーザよりも大きい光パルス出力が得られる。
また、本発明では半導体レーザからの光パルス出力を基
本波として波長変換素子に結合すると基本波の第二高調
波が発生するが、第二高調波は基本波の出力の２乗に比
例して変換されるため、第二高調波の高出力化が可能と
なる。Effect In the present invention, the semiconductor laser emits light in the gain region when a current is injected. When the light emission is small, the absorption is large in the saturable absorption region and the output light is at a low level, but the light emission becomes large. The absorption in the saturable absorption region begins to saturate,
When it exceeds the threshold value, laser oscillation occurs and the output light is in a high level state. In the semiconductor laser of the present invention, when gain switching is performed with a short current pulse, a larger optical pulse output than that of a normal semiconductor laser is obtained due to the synergistic effect of an increase in gain in the gain region and a decrease in absorption in the saturable absorption region. .
Further, in the present invention, when the optical pulse output from the semiconductor laser is coupled to the wavelength conversion element as the fundamental wave, the second harmonic of the fundamental wave is generated. The second harmonic is proportional to the square of the output of the fundamental wave. Since it is converted, it is possible to increase the output of the second harmonic.
実施例 第１図は本発明の第１の実施例による波長変換型超短光
パルス発生装置の概略構成を示すものであって、９は発
振波長0.83μmGaAlAs/GaAs系半導体レーザ、10はGaAlAs
活性層、11は長230μｍの利得領域、12,13はそれぞれ長
さ25μｍの可飽和吸収領域、14は電流注入を行うための
電極、２は波長変換素子、３は光導波路、4,5はレン
ズ、６はλ/2板である。半導体レーザ９の共振器端面20
はAl2O3とSi層の多層コーティングにより反射率96％の
高反射率であり、共振器端面21はAl2O3単層コーティン
グにより反射率３％の低反射率となっている。波長変換
素子２は、Z-cutのLiNbO3基板にプロトン交換により光
導波路３（幅×厚み＝1.6μｍ×0.36μｍ）を形成した
もので、基本波は最低次TM導波モード、高調波はTM放射
モードのチェレンコフ放射型のものである。第２図に半
導体レーザ９の電流一光出力特性を示す。端面反射率制
御により40mW以上の高出力が得られた。電極14よりしき
い値電流の0.7倍のバイアス電流とパルス幅400ps、繰り
返し周波数10MHzの短電流パルスを注入して半導体レー
ザ９を利得スイッチングすることにより、パルス幅20ps
以下、ピーク出力2W以上の従来の２倍以上の高出力の超
短光パルスが得られた。第３図に、両端に各５μm,1.5
μm,25μｍの可飽和吸収領域をもつ半導体レーザのピー
ク出力のバイアス電流依存性を示す。可飽和吸収の効果
が大きいほど大きいピーク出力が得られた。第２図の半
導体レーザ９から出射されたTEモード発振の光パルス
は、基本波７としてレンズ４でコリメートされ、λ/2板
６で偏光方向を90°変換された後レンズ５で集光されて
波長変換素子２に形成された光導波路３に入射する。こ
の際、光導波路３の中を導波するTM導波モードの基本波
をＴ放射モードの第二高調波の位相速度が等しくなり、
基本波７は波長0.415μｍの第二高調波の光パルス８に
変換されてチェレンコフ放射される。第二高調波出力は
基本波出力の２乗に比例して変換されるため、従来の４
倍以上のピーク出力約10mWの高出力でパルス幅10ps以下
の第二高調波が得られた。第４図（ａ），（ｂ）に光オ
シロスコープで観測した半導体レーザ光と第二高調波の
光パルス波形を示す。第５図は、本発明の第２の実施例
による超短光パルス発生装置における半導体レーザの概
略断面図を示すものであって、半導体レーザ15の共振器
内部に可飽和吸収領域16が設けられている。このような
レーザでは、可飽和吸収領域の長さを作製プロセスで用
いるマスクで設定できるため、同一ウェハ内で分留りよ
く同等の特性を示すものが得られた。第６図は、本発明
の第３の実施例による超短光パルス発生装置における半
導体レーザの概略断面図であって、半導体レーザ17の可
飽和吸収領域18に制御電極19が設けられている。利得領
域11と可飽和吸収領域18はエッチングによって溝20を形
成することにより、電気的に絶縁されている。第７図に
制御電極19への印加電圧を変化したときの利得領域11へ
の注入電流一光出力特性を示す。制御電極19への電圧を
変化すると可飽和吸収領域の吸収係数が変化するため、
しきい値電流が変化している。制御電極19への電圧を変
化することは、第１あるいは第２の実施例における半導
体レーザで、可飽和吸収領域長を変化することに対応し
ているが電圧を変化する場合には連続的に制御できるた
め、利得スイッチングを行ったときに光パルスのピーク
出力が最大となるように制御することができた。なお、
本実施例では半導体レーザとして波長0.8μｍ帯のGaAsA
s/GaAs系を用いたが、波長1.3μｍ帯および波長1.55μ
ｍ帯のInGaAsP/InP系あるいは波長0.6μｍ帯のAlGaInP/
GaAs系であっても同等の効果が得られ、波長変換も可能
である。Embodiment 1 FIG. 1 shows a schematic structure of a wavelength conversion type ultrashort optical pulse generator according to the first embodiment of the present invention, in which 9 is an oscillation wavelength of 0.83 μm GaAlAs / GaAs semiconductor laser and 10 is GaAlAs.
Active layer, 11 is a 230 μm long gain region, 12 and 13 are 25 μm long saturable absorption regions, 14 is an electrode for current injection, 2 is a wavelength conversion element, 3 is an optical waveguide, and 4 and 5 are The lens 6 is a λ / 2 plate. End facet 20 of semiconductor laser 9
Has a high reflectance of 96% due to the multi-layer coating of Al 2 O 3 and the Si layer, and the resonator end face 21 has a low reflectance of 3% due to the single layer coating of Al 2 O 3 . The wavelength conversion element 2 is a Z-cut LiNbO 3 substrate with an optical waveguide 3 (width × thickness = 1.6 μm × 0.36 μm) formed by proton exchange. The fundamental wave is the lowest TM waveguide mode and the harmonic wave is It is a Cherenkov radiation type of TM radiation mode. FIG. 2 shows current-light output characteristics of the semiconductor laser 9. A high output of 40 mW or more was obtained by controlling the edge reflectance. A bias current of 0.7 times the threshold current and a pulse width of 400 ps from the electrode 14 and a short current pulse with a repetition frequency of 10 MHz are injected to gain-switch the semiconductor laser 9 to obtain a pulse width of 20 ps.
From now on, an ultrashort optical pulse with a peak output of 2 W or more and twice as high as that of the conventional one was obtained. Fig. 3 shows that both ends are 5 μm and 1.5
The bias current dependence of the peak output of a semiconductor laser having a saturable absorption region of μm and 25 μm is shown. The larger the effect of saturable absorption, the larger the peak output obtained. The TE-mode oscillation light pulse emitted from the semiconductor laser 9 shown in FIG. 2 is collimated as a fundamental wave 7 by the lens 4, converted in polarization direction by 90 ° by the λ / 2 plate 6, and then condensed by the lens 5. And enters the optical waveguide 3 formed in the wavelength conversion element 2. At this time, the phase velocity of the second harmonic of the T radiation mode becomes equal to that of the fundamental wave of the TM guided mode guided in the optical waveguide 3,
The fundamental wave 7 is converted into an optical pulse 8 of a second harmonic having a wavelength of 0.415 μm and emitted by Cherenkov. Since the second harmonic output is converted in proportion to the square of the fundamental wave output,
The second harmonic with a pulse width of less than 10 ps was obtained at a high output of more than double the peak output of about 10 mW. FIGS. 4 (a) and 4 (b) show the optical pulse waveforms of the semiconductor laser light and the second harmonic observed by the optical oscilloscope. FIG. 5 is a schematic sectional view of a semiconductor laser in an ultrashort optical pulse generator according to a second embodiment of the present invention, in which a saturable absorption region 16 is provided inside a resonator of the semiconductor laser 15. ing. In such a laser, since the length of the saturable absorption region can be set by the mask used in the manufacturing process, a laser having good characteristics with good fractionation in the same wafer was obtained. FIG. 6 is a schematic sectional view of a semiconductor laser in an ultrashort optical pulse generator according to a third embodiment of the present invention, in which a saturable absorption region 18 of the semiconductor laser 17 is provided with a control electrode 19. The gain region 11 and the saturable absorption region 18 are electrically insulated by forming the groove 20 by etching. FIG. 7 shows the injection current-optical output characteristics to the gain region 11 when the voltage applied to the control electrode 19 is changed. Since the absorption coefficient of the saturable absorption region changes when the voltage to the control electrode 19 is changed,
The threshold current is changing. Changing the voltage to the control electrode 19 corresponds to changing the saturable absorption region length in the semiconductor laser of the first or second embodiment, but it continuously changes when the voltage changes. Since it can be controlled, the peak output of the optical pulse can be controlled to be maximum when the gain switching is performed. In addition,
In this embodiment, GaAsA having a wavelength of 0.8 μm is used as a semiconductor laser.
s / GaAs system was used, wavelength 1.3 μm band and wavelength 1.55 μ
m-band InGaAsP / InP system or wavelength 0.6 μm band AlGaInP /
Even if it is a GaAs system, the same effect can be obtained and wavelength conversion is possible.
発明の効果 以上の説明から明らかなように、本発明は、半導体レー
ザを利得領域と可飽和吸収領域を有する構成をすること
によって、ピーク出力の大きな超短光パルスが得られる
という効果を有するものである。また上記半導体レーザ
の光パルス出力を基本波として光導波路型波長変換素子
に入射すると、基本波の出力の２乗に比例した第二高調
波が得られるため、短波長の超短光パルスの高出力化が
可能となるという効果を有するものである。EFFECTS OF THE INVENTION As is clear from the above description, the present invention has an effect that an ultrashort optical pulse with a large peak output can be obtained by configuring a semiconductor laser having a gain region and a saturable absorption region. Is. When the optical pulse output of the semiconductor laser is input to the optical waveguide type wavelength conversion element as a fundamental wave, a second harmonic wave proportional to the square of the output of the fundamental wave is obtained. This has the effect of enabling output.
第１図は本発明の第１の実施例による波長変換型超短光
パルス発生装置の概略構成図、第２図は第１の実施例に
おける半導体レーザの電流一光出力特性図、第３図は可
飽和吸収領域の異なる半導体レーザのピーク出力のバイ
アス電流依存性図、第４図（ａ），（ｂ）は半導体レー
ザ光、第二高調波パルス波形図、第５図は本発明の第２
の実施例における半導体レーザの概略断面図、第６図は
本発明の第３の実施例における半導体レーザの概略断面
図、第７図は第３の実施例における半導体レーザの電流
一光出力特性図、第８図は従来例における波長変換形超
短光パルス発生装置の概略構成図である。 ２……波長変換素子、３……光導波路、9,15,17……半
導体レーザ、10……活性層、11……利得領域、12,13,1
6,18……可飽和吸収領域、14……電極、19……制御電
極。FIG. 1 is a schematic configuration diagram of a wavelength conversion type ultrashort optical pulse generator according to a first embodiment of the present invention, FIG. 2 is a current-optical output characteristic diagram of a semiconductor laser in the first embodiment, and FIG. Is a bias current dependence diagram of peak output of semiconductor lasers having different saturable absorption regions, FIGS. 4 (a) and 4 (b) are semiconductor laser light, second harmonic pulse waveform diagram, and FIG. Two
6 is a schematic sectional view of a semiconductor laser according to the embodiment of the present invention, FIG. 6 is a schematic sectional view of a semiconductor laser according to the third embodiment of the present invention, and FIG. 7 is a current-optical output characteristic diagram of the semiconductor laser according to the third embodiment. FIG. 8 is a schematic configuration diagram of a wavelength conversion type ultrashort optical pulse generator in a conventional example. 2 ... Wavelength conversion element, 3 ... Optical waveguide, 9,15,17 ... Semiconductor laser, 10 ... Active layer, 11 ... Gain region, 12, 13, 1
6,18 …… Saturable absorption region, 14 …… electrode, 19 …… control electrode.
Claims (5)
層及び閉じ込め層を含む共振器を備え、前記共振器の一
部が前記活性層に電流を注入するための電極を有する利
得領域であり、前記共振器の他部が可飽和吸収領域であ
る半導体レーザを短電流パルスで励起して利得スイッチ
ングすることを特徴とする超短光パルス発生装置。1. A resonator including at least an active layer and a confinement layer formed on a semiconductor substrate, wherein a part of the resonator is a gain region having an electrode for injecting a current into the active layer, An ultrashort optical pulse generator characterized in that a semiconductor laser in which the other part of the resonator is a saturable absorption region is excited by a short current pulse to perform gain switching.
発生装置と光導波路構造を有する波長変換素子が光学的
に結合した構造を備え、前記半導体レーザから出射され
る超短パルス光を基本波として前記波長変換素子に結合
し、前記波長変換素子からの出力光として前記基本波の
第二高調波を発生することを特徴とする波長変換型超短
光パルス発生装置。2. An ultrashort pulsed light emitted from the semiconductor laser, comprising a structure in which the ultrashort optical pulse generator according to claim 1 and a wavelength conversion element having an optical waveguide structure are optically coupled. Is a fundamental wave and is coupled to the wavelength conversion element to generate a second harmonic of the fundamental wave as output light from the wavelength conversion element.
射膜を有し、第２の端面が反射防止膜を有する出射端で
あることを特徴とする特許請求の範囲第１項又は第２項
記載の超短光パルス発生装置。3. The first end face of the resonator of the semiconductor laser has a high reflection film, and the second end face is an emission end having an antireflection film. The ultrashort optical pulse generator according to the second item.
体レーザ共振器端面から離れた前記共振器内部に備えた
ことを特徴とする特許請求の範囲第１項または第２項記
載の超短光パルス発生装置。4. The ultrashort light according to claim 1, wherein a saturable absorption region of a semiconductor laser is provided inside the resonator away from an end face of the semiconductor laser resonator. Pulse generator.
を有し、前記可飽和吸収領域と利得領域が電気的に絶縁
されていることを特徴とする特許請求の範囲第１項又は
第２項記載の超短光パルス発生装置。5. The saturable absorption region of the semiconductor laser has a control electrode, and the saturable absorption region and the gain region are electrically insulated from each other. The ultrashort optical pulse generator described in the paragraph.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1-170159 | 1989-06-30 | ||
| JP17015989 | 1989-06-30 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0387085A JPH0387085A (en) | 1991-04-11 |
| JPH07112095B2 true JPH07112095B2 (en) | 1995-11-29 |
Family
ID=15899778
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2135949A Expired - Lifetime JPH07112095B2 (en) | 1989-06-30 | 1990-05-25 | Ultrashort optical pulse generator |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH07112095B2 (en) |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP6893365B2 (en) * | 2019-06-25 | 2021-06-23 | 国立研究開発法人産業技術総合研究所 | Semiconductor laser |
| WO2021124390A1 (en) * | 2019-12-16 | 2021-06-24 | 三菱電機株式会社 | Heat exchanger, heat exchanger unit, and refrigeration cycle device |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61189686A (en) * | 1985-02-19 | 1986-08-23 | Matsushita Electric Ind Co Ltd | Laser device |
| JPS6281086A (en) * | 1985-10-04 | 1987-04-14 | Nec Corp | Optical transmitter |
| JPS62274685A (en) * | 1986-05-22 | 1987-11-28 | Mitsubishi Electric Corp | Semiconductor laser device |
| JPS63164379A (en) * | 1986-12-26 | 1988-07-07 | Matsushita Electric Ind Co Ltd | Photo output device |
| JPS63211785A (en) * | 1987-02-27 | 1988-09-02 | Nec Corp | Multiple quantum well type optical bistable semiconductor laser |
| JPS63221692A (en) * | 1987-03-10 | 1988-09-14 | Oki Electric Ind Co Ltd | Semiconductor light amplifier |
| JPS63272089A (en) * | 1987-04-30 | 1988-11-09 | Oki Electric Ind Co Ltd | Semiconductor laser array |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6421422A (en) * | 1987-07-17 | 1989-01-24 | Nippon Telegraph & Telephone | Optical flip-flop |
-
1990
- 1990-05-25 JP JP2135949A patent/JPH07112095B2/en not_active Expired - Lifetime
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61189686A (en) * | 1985-02-19 | 1986-08-23 | Matsushita Electric Ind Co Ltd | Laser device |
| JPS6281086A (en) * | 1985-10-04 | 1987-04-14 | Nec Corp | Optical transmitter |
| JPS62274685A (en) * | 1986-05-22 | 1987-11-28 | Mitsubishi Electric Corp | Semiconductor laser device |
| JPS63164379A (en) * | 1986-12-26 | 1988-07-07 | Matsushita Electric Ind Co Ltd | Photo output device |
| JPS63211785A (en) * | 1987-02-27 | 1988-09-02 | Nec Corp | Multiple quantum well type optical bistable semiconductor laser |
| JPS63221692A (en) * | 1987-03-10 | 1988-09-14 | Oki Electric Ind Co Ltd | Semiconductor light amplifier |
| JPS63272089A (en) * | 1987-04-30 | 1988-11-09 | Oki Electric Ind Co Ltd | Semiconductor laser array |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0387085A (en) | 1991-04-11 |
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