JPH01310583A - Variable wavelength laser device - Google Patents
Variable wavelength laser deviceInfo
- Publication number
- JPH01310583A JPH01310583A JP63142166A JP14216688A JPH01310583A JP H01310583 A JPH01310583 A JP H01310583A JP 63142166 A JP63142166 A JP 63142166A JP 14216688 A JP14216688 A JP 14216688A JP H01310583 A JPH01310583 A JP H01310583A
- Authority
- JP
- Japan
- Prior art keywords
- wavelength
- fringe
- laser
- center
- image sensor
- 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
- BJQHLKABXJIVAM-UHFFFAOYSA-N bis(2-ethylhexyl) phthalate Chemical compound CCCCC(CC)COC(=O)C1=CC=CC=C1C(=O)OCC(CC)CCCC BJQHLKABXJIVAM-UHFFFAOYSA-N 0.000 claims abstract description 17
- 230000003287 optical effect Effects 0.000 claims description 13
- 230000010355 oscillation Effects 0.000 claims description 8
- 238000000034 method Methods 0.000 abstract description 5
- 239000012634 fragment Substances 0.000 abstract description 2
- 238000010586 diagram Methods 0.000 description 6
- 238000001514 detection method Methods 0.000 description 5
- 230000004075 alteration Effects 0.000 description 3
- 230000005540 biological transmission Effects 0.000 description 3
- 230000007774 longterm Effects 0.000 description 3
- 229910052736 halogen Inorganic materials 0.000 description 2
- 150000002367 halogens Chemical class 0.000 description 2
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 1
- PXGOKWXKJXAPGV-UHFFFAOYSA-N Fluorine Chemical compound FF PXGOKWXKJXAPGV-UHFFFAOYSA-N 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 229910052801 chlorine Inorganic materials 0.000 description 1
- 239000000460 chlorine Substances 0.000 description 1
- 229910052731 fluorine Inorganic materials 0.000 description 1
- 239000011737 fluorine Substances 0.000 description 1
- 238000003384 imaging method Methods 0.000 description 1
- 238000005372 isotope separation Methods 0.000 description 1
- 229910052743 krypton Inorganic materials 0.000 description 1
- DNNSSWSSYDEUBZ-UHFFFAOYSA-N krypton atom Chemical compound [Kr] DNNSSWSSYDEUBZ-UHFFFAOYSA-N 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000010453 quartz Substances 0.000 description 1
- 238000002310 reflectometry Methods 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
- 229910052724 xenon Inorganic materials 0.000 description 1
- FHNFHKCVQCLJFQ-UHFFFAOYSA-N xenon atom Chemical compound [Xe] FHNFHKCVQCLJFQ-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/10—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
- H01S3/106—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating by controlling devices placed within the cavity
- H01S3/1062—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating by controlling devices placed within the cavity using a controlled passive interferometer, e.g. a Fabry-Perot etalon
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/10—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
- H01S3/13—Stabilisation of laser output parameters, e.g. frequency or amplitude
- H01S3/136—Stabilisation of laser output parameters, e.g. frequency or amplitude by controlling devices placed within the cavity
- H01S3/137—Stabilisation of laser output parameters, e.g. frequency or amplitude by controlling devices placed within the cavity for stabilising of frequency
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/14—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range characterised by the material used as the active medium
- H01S3/22—Gases
- H01S3/223—Gases the active gas being polyatomic, i.e. containing two or more atoms
- H01S3/225—Gases the active gas being polyatomic, i.e. containing two or more atoms comprising an excimer or exciplex
Landscapes
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Engineering & Computer Science (AREA)
- Plasma & Fusion (AREA)
- Optics & Photonics (AREA)
- Spectrometry And Color Measurement (AREA)
- Lasers (AREA)
Abstract
Description
【発明の詳細な説明】
産業上の利用分野
本発明は微細加工に用いる波長可変レーザ装置に関する
ものである。DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a wavelength tunable laser device used for microfabrication.
従来の技術
近年、＠軸加工用の光源として、紫外域で発振するレー
ザ装置が注目されている。中でもエキシマレーザは、レ
ーザ媒質であるクリプトン、キセノンなどの希ガスとふ
っ素、塩素などのハロゲンガスの組み合わせによシ、３
５３ ｎｍから１９３ｎｍの間のいくつかの波長で強力
な発振線を得ることができる。BACKGROUND OF THE INVENTION In recent years, laser devices that oscillate in the ultraviolet region have attracted attention as light sources for @-axis machining. Among them, excimer lasers use a combination of a rare gas such as krypton or xenon as a laser medium and a halogen gas such as fluorine or chlorine.
Strong oscillation lines can be obtained at several wavelengths between 53 nm and 193 nm.
これらエキシマレーザの利得バンド幅は約１ｎｍと広く
、光共振器と組み合わせて発振させた場合、発振線が０
．５ｎｍ程度の線幅（半値全幅）を持つ。The gain bandwidth of these excimer lasers is as wide as approximately 1 nm, and when oscillated in combination with an optical resonator, the oscillation line is 0.
．． It has a line width (full width at half maximum) of about 5 nm.
このように比較的広い線幅を持つレーザ装置を光源とし
て用いた場合、光の伝送系に色収差を補正した光学系を
採用する必要がある。ところが、波長が３５０ｎｍ以下
の紫外域では、光学系に用いるレンズの光学材料の選択
の幅が限られ、色収差補正が困難となる。したがって、
波長３５０ ｎｍ以下のエキシマレーザを利用する場合
、発振線の線幅を０．Ｏ０５ｎｍ程度にまで単色化する
ことが行なわれている。これによυ、色収差補正しない
光学系が利用可能となシ、レーザ光を利用する装置の光
学系の簡略化、さらには小型化、価格の低減を実現でき
る。When a laser device having such a relatively wide line width is used as a light source, it is necessary to employ an optical system that corrects chromatic aberration for the light transmission system. However, in the ultraviolet region where the wavelength is 350 nm or less, the range of selection of optical materials for lenses used in the optical system is limited, making it difficult to correct chromatic aberration. therefore,
When using an excimer laser with a wavelength of 350 nm or less, the line width of the oscillation line should be set to 0. Monochromatization to about O05 nm is being carried out. As a result, an optical system that does not correct chromatic aberration can be used, and the optical system of a device that uses laser light can be simplified, further downsized, and reduced in price.
またこのようにエキシマレーザの発振波長を単色化した
場合、その中心波長は利得バンド幅内の任意の値に設定
可能である。したがって、発振波長を精密に設定できる
機構をエキシマレーザ本体に内蔵すれば、波長可変の紫
外線レーザ装置として、微細加工のほか、化学反応の制
御、同位体の分離など幅広い用途が開けてくる。Further, when the oscillation wavelength of the excimer laser is made monochromatic in this way, the center wavelength can be set to any value within the gain bandwidth. Therefore, if a mechanism that can precisely set the oscillation wavelength is built into the excimer laser body, a wavelength-tunable ultraviolet laser device can be used for a wide range of applications, including microfabrication, control of chemical reactions, and isotope separation.
本発明者らはすでに、上記目的を達成するレーザ装置の
一構成を提案した。すなわち、本体内部にレーザ光の中
心波長を検出する手段を組み込んで、発振波長を任意の
値に設定できる波長可変レーザ装置である。このような
レーザ装置を実現するためには、レーザ光の中心波長を
精密に検出し制御する方法が必要になる。レーザ光の中
心波長を検出する方法についてもいくつかの提案があシ
、たとえば特願昭６２−２４２３７８号においては、レ
ーザ光の一部をファプリ・ベローエタゴンに入射し、作
られる干渉縞の位置をイメージセンサ等で読み取ってレ
ーザ光の中心波長を検出する方法が述べられている。The present inventors have already proposed a configuration of a laser device that achieves the above object. In other words, it is a wavelength tunable laser device in which means for detecting the center wavelength of laser light is built into the main body, and the oscillation wavelength can be set to an arbitrary value. In order to realize such a laser device, a method for precisely detecting and controlling the center wavelength of laser light is required. There have been several proposals for methods of detecting the center wavelength of laser light. For example, in Japanese Patent Application No. 62-242378, a part of the laser light is incident on the Fabry-Bello etagon, and the position of the interference fringes created is determined. A method is described in which the center wavelength of laser light is detected by reading it with an image sensor or the like.
ファプリ豐ペローエタロンは、大型のグレーティング分
光器と同等の分解能を持つ波長検出器をきわめて小規模
な装置で実現できるので、木発明者らが提案している、
中心波長を制御する機構を内蔵したレーザ装置に最適の
波長検出素子の一つである。The Fabry Perot etalon has been proposed by the inventors of the tree because it can realize a wavelength detector with the same resolution as a large grating spectrometer with an extremely small-scale device.
It is one of the most suitable wavelength detection elements for laser devices that have a built-in mechanism to control the center wavelength.
発明が解決しようとする課題
しかし、このような従来の波長可変レーザ装置では、長
期間の使用中に周囲温度の履歴や振動等によって、ファ
ブリ舎ペローエタロンとイメージセンサの位置関係に狂
いを生じ、レーザ光の中心波長が変化していないのにも
かかわらず、あたかも変化があったかのような誤った信
号を出力してしまい、その結果レーザ光の中心波長が変
動するという課題があった。Problems to be Solved by the Invention However, with such conventional wavelength tunable laser devices, the positional relationship between the Fabry-Perot etalon and the image sensor becomes distorted due to ambient temperature history, vibration, etc. during long-term use. Despite the fact that the center wavelength of the laser beam has not changed, an erroneous signal is output as if there has been a change, resulting in a problem in that the center wavelength of the laser beam fluctuates.
本発明はこのような課題を解決するためになされたもの
で、長期間にわたってレーザ光の中心波長を一定値に拘
束できる波長可変レーザ装置を提供するものである。The present invention has been made to solve these problems, and provides a wavelength tunable laser device that can restrict the center wavelength of laser light to a constant value over a long period of time.
課題を解決するための手段
この課題を解決するため本発明は、レーザ媒質と、全反
射鏡および出力誂とからなる光共振器を具備し、単一ま
たは複数の波長選択素子を前記光共振器中に設置してレ
ーザ媒質の利得バンド幅内で発振波長の中心値を可変に
したレーザ装置において、前記波長選択素子の選択波長
を制御する手段、およびレーザ光の中心波長を検出する
手段をレーザ装置内に内蔵したものであって、前記波長
検出手段がフェプリ・ペローエタロンによっテ投影され
たフリンジパターンの直径を測定するようにしたもので
ある。Means for Solving the Problems In order to solve the problems, the present invention comprises an optical resonator comprising a laser medium, a total reflection mirror, and an output mirror, and a single or plural wavelength selection elements are connected to the optical resonator. In a laser device in which the center value of the oscillation wavelength is varied within the gain bandwidth of the laser medium by being installed inside the laser medium, means for controlling the selected wavelength of the wavelength selection element and means for detecting the center wavelength of the laser beam are provided in the laser. The wavelength detecting means is built into the apparatus and measures the diameter of the fringe pattern projected by the Fepry-Perot etalon.
作 用
この構成により、単色化したレーザ光の中心波長を長期
間にわたって一定値に拘束できることとなる。Function: With this configuration, the center wavelength of monochromatic laser light can be constrained to a constant value over a long period of time.
実施例
第１図は本発明の一実施例であるエキシマレーザの構成
図である。第１図において本発明の実施例のレーザ装置
は希ガスとハロゲンガスの混合気体をレーザ媒質とする
放電管１と、全反射鏡２および出力鏡からなる光共振器
により、紫外域でレーザ発振する。光共振器の光軸上に
はエアスペースエタロン４が置かれている。エアスペー
スエタロン４は、レーザ波長において適当な反射率を持
つ２枚の平行平面石英板を微小なギャップを保って向き
合わせたファプリーベローエタロンの一種であシ、ギャ
ップ間の距離およびギャップ間の気体の屈折率で決まる
特定の波長のみを透過する。波長選択素子の一種である
。エアスペースエタロン４は気密容器６中に設置されて
いる。気密容器５には高圧空気源θおよび低圧空気源子
がそれぞれパルプ８．９を介して接続されており、エア
スペースエタロン４のギャップ間の気圧を変化させるこ
とができる。また半透過鏡１０によって取υ出されたサ
ンプルビームは、波長検出器１１に導かれる。波長検出
器１１はサンプルビームの中心波長に応じた信号を信号
処理回路１２に出力する。信号処理回路１２は波長検出
器１１から送られた信号に応じてバルブ８またはパルプ
９を開閉する信号を出力する。Embodiment FIG. 1 is a block diagram of an excimer laser which is an embodiment of the present invention. In FIG. 1, a laser device according to an embodiment of the present invention oscillates a laser in the ultraviolet region by an optical resonator consisting of a discharge tube 1 using a mixture of rare gas and halogen gas as a laser medium, a total reflection mirror 2, and an output mirror. do. An air space etalon 4 is placed on the optical axis of the optical resonator. The air space etalon 4 is a type of fapley bellows etalon in which two parallel plane quartz plates with appropriate reflectivity at the laser wavelength are faced with a small gap between them. Only specific wavelengths determined by the refractive index of the gas are transmitted. It is a type of wavelength selection element. The air space etalon 4 is installed in an airtight container 6. A high-pressure air source θ and a low-pressure air source are connected to the airtight container 5 via pulps 8.9, respectively, and the air pressure between the gaps of the air space etalon 4 can be changed. Further, the sample beam taken out by the semi-transmissive mirror 10 is guided to a wavelength detector 11. The wavelength detector 11 outputs a signal corresponding to the center wavelength of the sample beam to the signal processing circuit 12. The signal processing circuit 12 outputs a signal to open or close the valve 8 or the pulp 9 according to the signal sent from the wavelength detector 11.
次に以上のような構成による、本発明の波長可変レーザ
装置の動作を説明する。一般にエキシマレーザのスペク
ト／し線幅は第２図（ａ）に示すように０．５ｎｍに及
ぶ。この線幅を第２図［有］）に示すように１００分の
１程度に単色化する場合、透過帯域幅がそれと同程度の
波長選択素子を用いる必要がある。このような波長選択
素子は、たとえば実施例に示したようにエアスペースエ
タロンで実現できる。Next, the operation of the wavelength tunable laser device of the present invention having the above configuration will be explained. Generally, the spectrum/line width of an excimer laser ranges to 0.5 nm, as shown in FIG. 2(a). When this line width is made monochromatic to about 1/100 as shown in FIG. 2, it is necessary to use a wavelength selection element with a transmission band width of about the same level. Such a wavelength selection element can be realized, for example, by an air space etalon as shown in the embodiment.
このようにして単色化したレーザ光の中心波長は、波長
選択素子の透過中心波長を制御することによって、レー
ザ媒質の利得バンド幅内で自由に変化させることができ
る。本発明によるレーザ装置では波長検出器１１を設け
、レーザ光の中心波長に相当する波長信号を得て波長選
択素子の選択波長を制御し、レーザ光の中心波長を目的
の値に一致させている一波長選択素子の選択波長を制御
するためには、たとえば第１図の実施例に示したように
、エアスペースエタロン４を気密室６内に設関し、信号
処理回路１２からの偏差信号に応じて、高圧空気源６と
の間のパルプ８または低圧空気源子との間のパルプ９を
開閉して、気密室ε内の気圧を変えることによってエア
スペースエタロン４のギャップ間の屈折率を調節すれば
よい。The center wavelength of the monochromatic laser beam can be freely changed within the gain bandwidth of the laser medium by controlling the transmission center wavelength of the wavelength selection element. The laser device according to the present invention is provided with a wavelength detector 11 to obtain a wavelength signal corresponding to the center wavelength of the laser beam and control the selected wavelength of the wavelength selection element to match the center wavelength of the laser beam to a target value. In order to control the selected wavelength of one wavelength selection element, for example, as shown in the embodiment shown in FIG. The refractive index between the gaps of the air space etalon 4 is adjusted by opening and closing the pulp 8 between the high-pressure air source 6 or the pulp 9 between the low-pressure air source and changing the air pressure in the airtight chamber ε. do it.
波長検出器１１を実現するには、たとえば第３図に示す
ようにエアスペースエタロン１３にょ）、レーザ発振の
スペクトルを同心円上のフリンジパターンに展開して結
像し、特定のフリンジ２４の位置をリニアイメージセン
サ１５などで読み取ればよい。In order to realize the wavelength detector 11, for example, as shown in FIG. It may be read using the linear image sensor 15 or the like.
このような構成の波長検出器でレーザ光の中心波長を一
定値に保つためには、一定波長のレーザ光が入射したと
き常に同じ位置にフリンジ１４ができなければならない
。しかし、周囲温度の履歴や振動等によって、エアスペ
ースエタロン１３とリニアイメージセンサ１５の位置関
係が狂ウド、フリンジ１４の結像位置が変化し、波長変
化があったような信号を出力する。その結果、レーザ光
の中心波長が設定値から変動してしまい、おおむね１ケ
月以内に、外部の波長基準を用いた波長校正が必要とな
るのが現状であった。In order to maintain the center wavelength of the laser beam at a constant value in a wavelength detector having such a configuration, a fringe 14 must always be formed at the same position when a laser beam of a constant wavelength is incident. However, due to the history of ambient temperature, vibrations, etc., the positional relationship between the air space etalon 13 and the linear image sensor 15 is disturbed, the imaging position of the fringe 14 changes, and a signal with a wavelength change is output. As a result, the center wavelength of the laser beam fluctuates from the set value, and the current situation is that wavelength calibration using an external wavelength standard is required within about one month.
そこで本発明による波長検出器は、第１図の実施例に示
したようにリニアイメージセンサ１６をフリンジ１４の
中心上を通るように配置しかつ、リニアイメージセンサ
１５上に投影されたフリンジ断片間の距離を読み取るよ
うに構成したものである。外的な要因によって、エアス
ペースエタロン１３とリニアイメージセンサ１６の位置
関係に狂いが生じても、フリンジ１４の直径の変化はそ
の位置の変化はど大きくない。したがって、第１図の実
施例によれば波長検出器の長期間の安定性を飛躍的に高
めることができる。Therefore, in the wavelength detector according to the present invention, the linear image sensor 16 is arranged so as to pass over the center of the fringe 14 as shown in the embodiment of FIG. It is configured to read the distance between. Even if the positional relationship between the air space etalon 13 and the linear image sensor 16 is distorted due to an external factor, the change in the diameter of the fringe 14 or the position thereof will not be large. Therefore, according to the embodiment shown in FIG. 1, the long-term stability of the wavelength detector can be dramatically improved.
第４図は本発明の異なる実施例による波長検出方法を説
明する図である。第４図の実施例においては、リニアイ
メージセンサ１６はフリンジ１４の直径上にないが信号
処理回路１２によって演算処理を行々い、フリンジ１４
の直径を算出している。すなわち、第６図に示すように
リニアイメージセンサの受光部は一定の面積を持ってい
るので、リニアイメージセンサ１６がフリンジ１４の直
径上からはずれていると光強度信号が非対称となる。FIG. 4 is a diagram illustrating a wavelength detection method according to a different embodiment of the present invention. In the embodiment shown in FIG. 4, although the linear image sensor 16 is not located on the diameter of the fringe 14, the signal processing circuit 12 performs arithmetic processing on the fringe 14.
Calculating the diameter of That is, as shown in FIG. 6, since the light receiving portion of the linear image sensor has a fixed area, if the linear image sensor 16 is deviated from the diameter of the fringe 14, the light intensity signal becomes asymmetrical.
この対称性からのずれ量をＩとすると、フリンジ１４の
中心からリニアイメージセンサ１５ｔで（７）距離２は
、Ｉに対して単調増加する関数ｆでｚ＝ｆ（ｘ）
と表わせる。したがってフリンジ１４の直径りは、リニ
アイメージセンサ１５上に投影されたフリンジ断片の間
隔をＬとして、
Ｄ＝Ｌ２＋４□２
と算出できることになる。したがって、Ｄが一定になる
ようにパルプ８，９を開閉すればレーザ光の中心波長は
一定に保たれる。第４図の実施例においては、リニアイ
メージセンサ１６は必ずしもフリンジ１４の直径上にな
くてもよく、波長読み取シ精度の安定性はさらに向上す
る。If the amount of deviation from this symmetry is I, the distance 2 from the center of the fringe 14 to the linear image sensor 15t (7) can be expressed as z=f(x) using a function f that monotonically increases with respect to I. Therefore, the diameter of the fringe 14 can be calculated as D=L2+4□2, where L is the interval between the fringe fragments projected onto the linear image sensor 15. Therefore, if the pulps 8 and 9 are opened and closed so that D remains constant, the center wavelength of the laser beam can be kept constant. In the embodiment of FIG. 4, the linear image sensor 16 does not necessarily have to be on the diameter of the fringe 14, and the stability of wavelength reading accuracy is further improved.
第６図も本発明の異なる実施例を示したものである。第
５図においては、２次元イメージセンサ１９を用いて、
同一円周上にある２点の間隔の最大値を測定することに
よって、フリンジ１４の直径を読み取っている。第６図
の実施例においては、フリンジ１４は２次元イメージセ
ンサ１９上のどの部分に投影されていてもよく、第４図
の実施例と同等の波長読み取シ精度の安定性が達成でき
る。FIG. 6 also shows a different embodiment of the present invention. In FIG. 5, using the two-dimensional image sensor 19,
The diameter of the fringe 14 is read by measuring the maximum value of the distance between two points on the same circumference. In the embodiment shown in FIG. 6, the fringe 14 may be projected onto any part of the two-dimensional image sensor 19, and the same stability in wavelength reading accuracy as in the embodiment shown in FIG. 4 can be achieved.
以上のような構成を有するので、本発明実施例の波長可
変レーザ装置は、設定した中心波長で長期間安定に発振
を続けることができる。発明者らが長期の波長安定性を
試験した結果、６ケ月以上にわたって中心波長を±０
、００１ ｎｍ以内に保つことができる。With the above configuration, the wavelength tunable laser device according to the embodiment of the present invention can continue to oscillate stably at the set center wavelength for a long period of time. The inventors tested long-term wavelength stability and found that the center wavelength remained at ±0 for over 6 months.
, 001 nm or less.
なお実施例では、レーザ装置としてエキシマレーザを用
いたものとして説明したが、本発明は波長可変レーザ一
般に適用できる。Although the embodiment has been described using an excimer laser as the laser device, the present invention can be applied to wavelength tunable lasers in general.
発明の詳細
な説明したように、本発明はファプリベｏ −エタロン
によって結像されたフリンジパターンの直径を測定する
ことによシ、単色化したレーザ光の中心波長を長期間に
わたって一定値に拘束できるというすぐれた特徴を有す
る波長可変レーザ装置を提供することができるものであ
る。As described in detail, the present invention makes it possible to constrain the center wavelength of monochromatic laser light to a constant value over a long period of time by measuring the diameter of the fringe pattern imaged by the Faprivé O-etalon. This makes it possible to provide a wavelength tunable laser device having these excellent features.
第１図は本発明の一実施例である波長可変レーザ装置の
構成図、第２図はレーザ光の単色化を説明するだめの図
、第３図は本発明による波長検出方法の一実施例を示す
図、第４図は本発明による波長検出方法の第２の実施例
を示す図、第６図は第２の実施例の原理を示す図、第６
図は本発明による波長検出方法の第３の実施例を示す図
である。
１・・・・・・放電管、２・・・・・・全反射鏡、３・
・・・・・出力鏡、４・・・・・・エアスペースエタロ
ン、５・・・・・・Ｋ 密容’ｌｆｔ、６・・・・・・
高圧空気源、了・・・・・・低圧空気源、８，９・・・
・・・パルプ、１０・・・・・・半透過鏡、１１・・・
・・・波長検出器、１２・・・・・・信号処理回路、１
３・・・・・・エアスペースエタロン、１４・・・・・
・フリンジ、１６・・・・・・リニアイメージセンサ、
１θ・・・・・・レンズ、１７・・・・・・械散板、１
８・・・・・・反射鏡、１９・・・・・・２次元イメー
ジセンサ。
代理人の氏名 弁理士 中 尾 敏 男 ほか１名第
４ 図
第５図Fig. 1 is a configuration diagram of a wavelength tunable laser device that is an embodiment of the present invention, Fig. 2 is a diagram for explaining monochromatic laser light, and Fig. 3 is an embodiment of a wavelength detection method according to the present invention. FIG. 4 is a diagram showing a second embodiment of the wavelength detection method according to the present invention. FIG. 6 is a diagram showing the principle of the second embodiment.
The figure shows a third embodiment of the wavelength detection method according to the present invention. 1...discharge tube, 2...total reflection mirror, 3.
...Output mirror, 4...Air space etalon, 5...K Confidence 'lft, 6...
High pressure air source, finished...Low pressure air source, 8,9...
...Pulp, 10...Semi-transparent mirror, 11...
... Wavelength detector, 12 ... Signal processing circuit, 1
3... Air Space Etalon, 14...
・Fringe, 16...Linear image sensor,
1θ...Lens, 17...Mechanical scattering plate, 1
8... Reflector, 19... Two-dimensional image sensor. Name of agent: Patent attorney Toshio Nakao and 1 other person
4 Figure 5
Claims (1)
器を具備し、単一または複数の波長選択素子を前記光共
振器中に設置してレーザ媒質の利得バンド幅内で発振波
長の中心値を可変にしたレーザ装置において、前記波長
選択素子の選択波長を制御する手段、およびレーザ光の
中心波長を検出する手段をレーザ装置内に内蔵したもの
であって、前記波長検出手段がファブリ・ペローエタロ
ンによって投影されたフリンジパターンの直径を測定す
ることを特徴とする波長可変レーザ装置。It is equipped with an optical resonator consisting of a laser medium, a total reflection mirror, and an output mirror, and a single or plural wavelength selection elements are installed in the optical resonator to select the center of the oscillation wavelength within the gain bandwidth of the laser medium. In a laser device with a variable value, a means for controlling the selected wavelength of the wavelength selection element and a means for detecting the center wavelength of the laser beam are built into the laser device, and the wavelength detecting means is fabricated. A wavelength tunable laser device characterized by measuring the diameter of a fringe pattern projected by a Perot etalon.
Priority Applications (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63142166A JP2537970B2 (en) | 1988-06-09 | 1988-06-09 | Wavelength tunable laser device |
| CA000578540A CA1302548C (en) | 1987-09-28 | 1988-09-27 | Laser apparatus |
| DE3889831T DE3889831T2 (en) | 1987-09-28 | 1988-09-27 | Laser apparatus. |
| EP88115902A EP0310000B1 (en) | 1987-09-28 | 1988-09-27 | Laser apparatus |
| US07/499,206 US4991178A (en) | 1987-09-28 | 1990-03-19 | Laser apparatus |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63142166A JP2537970B2 (en) | 1988-06-09 | 1988-06-09 | Wavelength tunable laser device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01310583A true JPH01310583A (en) | 1989-12-14 |
| JP2537970B2 JP2537970B2 (en) | 1996-09-25 |
Family
ID=15308893
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63142166A Expired - Lifetime JP2537970B2 (en) | 1987-09-28 | 1988-06-09 | Wavelength tunable laser device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2537970B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02153583A (en) * | 1988-12-06 | 1990-06-13 | Mitsubishi Electric Corp | Controller for stabilizing wavelength |
| JPH11289116A (en) * | 1998-02-03 | 1999-10-19 | Matsushita Electric Ind Co Ltd | Etalon evaluating method and device as well as laser oscillator |
| JP2019179934A (en) * | 2015-05-22 | 2019-10-17 | サイマー リミテッド ライアビリティ カンパニー | Spectral feature metrology of pulsed light beam |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6442877A (en) * | 1987-08-10 | 1989-02-15 | Nikon Corp | Excimer laser wavelength band narrowing device |
| JPS6484681A (en) * | 1987-09-26 | 1989-03-29 | Mitsubishi Electric Corp | Laser apparatus |
-
1988
- 1988-06-09 JP JP63142166A patent/JP2537970B2/en not_active Expired - Lifetime
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6442877A (en) * | 1987-08-10 | 1989-02-15 | Nikon Corp | Excimer laser wavelength band narrowing device |
| JPS6484681A (en) * | 1987-09-26 | 1989-03-29 | Mitsubishi Electric Corp | Laser apparatus |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02153583A (en) * | 1988-12-06 | 1990-06-13 | Mitsubishi Electric Corp | Controller for stabilizing wavelength |
| JPH11289116A (en) * | 1998-02-03 | 1999-10-19 | Matsushita Electric Ind Co Ltd | Etalon evaluating method and device as well as laser oscillator |
| JP2019179934A (en) * | 2015-05-22 | 2019-10-17 | サイマー リミテッド ライアビリティ カンパニー | Spectral feature metrology of pulsed light beam |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2537970B2 (en) | 1996-09-25 |
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