JP2005009956A - Laser apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To acquire a laser apparatus for speedily directing the optical axes of laser beams in desired emergent directions or in incident directions at the output of the laser beam into space. <P>SOLUTION: The laser apparatus is constituted by connecting a laser oscillator to an optical switch, providing a plurality of laser aperture parts for outputting the laser beams in different orientations, and connecting the laser aperture parts each to a plurality of optical fibers distributed and connected from the optical switch. The laser apparatus outputs the laser beams to surrounding space from the laser aperture parts having a target detected by a camera within aperture planes by selecting the laser aperture parts to output the laser beams. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【００４６】
図８（ｃ）は、光ミクサ９４から出力されるビート光の波形を示す図である。光ミクサ９４は、図８（ｂ）に示す変調信号Ｓｏと受信光から、その差分信号として図８（ｃ）に示すビート光を出力する。ここで、図８（ｂ）と図８（ｃ）でＴ１とＴ２がそれぞれ一致するので、図８（ｃ）のビート光の示す台形波形のボトムからトップに遷移する際の、下側遷移点Ｐ１（台形波形の下の頂点）と上側遷移点Ｐ２（台形波形の上の頂点）を、受光素子１１ｂで計測すれば、点Ｐ１と点Ｐ２の間の時間を求めることによって距離を計測することができる。具体的には、
距離Ｄ＝（Ｔ２−Ｔ１）×Ｃ／２ （式（２））
で求めることができる。
また、点Ｐ１と点Ｐ２の周波数を用いて速度を計測することができる。具体的には、次式（３）によって速度Ｖｒを求めることができる。レーザ受信器１１が光信号から電気信号への変換を行って受信データ信号Ｓｉを出力し、信号処理部４がこの受信データ信号Ｓｉに基づいて、これらの距離と速度の計測を行う（詳細は後述する）。
【００４７】
【数２】

【００４８】
図９は信号処理部４の構成を示す図である。図において、信号処理部４は、画像処理器１０１、測距器１０２、スイッチ選択器１０３、制御器１０４、姿勢方位基準器３０４で構成される。
画像処理器１０１は、カメラ１６から出力された画像信号が電気信号ケーブル１８ａを通じて入力される。画像処理器１０１は、カメラ１６からの画像信号に基づいて被写体の中から目標を示す像（目標）を抽出する。また、画像処理器１０１は、この抽出した目標の未来位置を予測する。制御器１０４は、複数のレーザ開口部１５の中から、目標の未来位置がレーザ光照射領域内に入るようなレーザ開口部１５と、レーザの指向方向を選択し、選択したレーザ開口部１５毎に、レーザの指向方向に対応するスイッチ情報をスイッチ選択器１０３に送信する。スイッチ選択器１０３は、レーザ開口部１５と指向方向に対応したスイッチ情報に基づいて、電気信号ケーブル２０ａを介して、光スイッチ１２、および光スイッチ６１に切替え信号を送信する。これによって、光スイッチ１２および光スイッチ６１が、レーザ開口部１５およびフェルール６３とレーザ送信器１０の間の光路を接続する。測距器１０２は、電気信号ケーブル２０ｃを介して、電源部５にレーザ発射指令信号を送出し、目標にレーザ光が照射できるタイミングでレーザ送信器１０からレーザ光を出射させる。また、測距器１０２は、電気信号ケーブル２０ｂを介してレーザ送信器１０のドライバ回路８２に変調信号Ｓｏを送出し、変調電圧信号Ｖｍと、バイアス信号Ｖｂを発生させる信号発生器として動作する。また、測距器１０２は、電気信号ケーブル２０ｄを介してレーザ受信器１１に変調信号Ｓｏを送出した受信光を変調させると共に、受信ケーブル２０ｄを介してレーザ受信器１１に入力された受信データ信号Ｓｉに基づいて、上述の式（２）、（３）より、外部空間に出力されたレーザ光の反射点までの距離Ｄと、その反射点の速度Ｖｒを求める。
【００４９】
次に、画像処理器１０１の詳細構成について、図１０を用いて説明する。
画像処理器１０１は、画像検出器１１１、目標抽出器１１２、予測演算器１１３、および目標データベース１１５で構成される。画像検出器１１１は、姿勢方位基準器３０４から、機体情報１９ｃとして機体の高度、速度、加速度、姿勢角、姿勢角速度、姿勢角加速度を入力し、カメラ１６で撮影された画像に対し座標変換を行うと共に、画像中から、空間フィルタや二値化処理や相関処理などの周知の画像処理技術によって、一塊の画素で構成される像を抽出する。姿勢方位基準器３０４は、高度計やジャイロなどにより構成される。
【００５０】
目標抽出器１１２は、抽出された像からの照度（照度情報）、像の輪郭形状（形状情報）を抽出し、像の重心の動きを計測して像の軌跡パターン（軌跡パターン情報）を抽出する。これら抽出された照度情報、形状情報、軌跡パターン情報は像情報と称する。目標抽出器１１２は、軌跡パターンが、像が直線的に移動する長さが一定以上の場合に、直線的な移動であると判別する。また、目標抽出器１１２は、軌跡パターン情報における像の移動の方向に基づいて、像が水平移動か、上昇移動か、下降移動か、ランダム移動か、位置固定であるのかなどを判別する。また、目標抽出器１１２は、軌跡パターン情報が、その直線的な移動が行われる高さが水平面から、画像内で所定画素以上上方にあれば、カメラ１６よりも高い高度に存在していると判定する。目標データベース１１５は、検出の対象とする目標の特徴を示す目標情報が予め格納されている。この目標情報には、上記像情報に対応して、検出対象の目標毎に、照度情報、形状情報、軌跡パターン情報、判別情報などが納められている。判別情報は、予め目標として選択すべきものと、目標外として選択すべきものでないものとの区別を示す情報である。
【００５１】
図１１の表は、目標データベース１１５のデータ構成例を示す図であって、検出対象目標に対応して、各目標毎の目標情報の一例を示す。目標データベース１１５は、表に示すようにメモリ領域内に仮想的に２次元マトリックスを構成しており、当該マトリックスの行（ＣＯＬ）に検出対象目標の名称が格納され、列（ＲＯＷ）が各検出対象目標に対応した目標情報を示している。目標抽出器１１２は、目標データベース１１５に格納された目標情報を参照して、先に抽出された像情報との比較によって、像情報と最も近い特徴の目標情報を有する検出対象目標を、目標と判定する。
【００５２】
例えば、図１２に示すように、画像検出器１１１で検出された画像内に、目標の対象となる航空機２０１やロケット２０２などの飛しょう体が存在すると同時に、目標以外の雲２０３に該当する画像や、海面反射２０４が含まれる場合を想定する。
【００５３】
図によれば、ロケット２０２や航空機２０１は、後方から噴出ガスを発生するため、カメラ１６が赤外線画像として捉えた際にロケット２０２や航空機２０１からの照度が比較的高いので、照度が低い雲と識別できる。また、ロケットや航空機は、カメラ１６の画面内に高照度（比較的高い照度）の像が直線的な軌跡パターンに沿って水平方向かもしくは上方へ移動する。一方、海面反射は海面からの照度が高いが、その位置が目標データベース１１５にあるロケットや航空機と異なる軌跡をとり、像の形状が大きいため、ロケットや航空機の像と識別が可能である。このような特徴点を踏まえて、複数の像の中から目標の像を選択することができる。
【００５４】
例えば、目標として、航空機２０１もしくはロケット２０２を選択したい場合、画像内の像の特徴に基づいて、照度情報が中照度（比較的中程度の照度）を示し、形状情報が小さく、軌跡パターン情報が直線的に水平移動するものを、目標抽出器１１２が航空機２０１であると判定し、第１の目標として選択する。また、照度情報が高照度を示し、形状情報が小さく、軌跡パターン情報が水平面より下から直線的に上昇するものを、目標抽出器１１２がロケット２０２であると判定し、第２の目標として選択する。
【００５５】
次に、画像内で目標として選択された対象について、目標抽出器１１２は、その画面内での重心位置を、夫々目標の存在位置として検出する。図１２の例では、重心位置Ｇ１、Ｇ２を、夫々第１、第２の目標の存在位置と判定する。第１、第２の目標は位置ＯＧ１、ＯＧ２において、画面内で出現し、像の軌跡から像の移動方向を求めて、さらに像の画像内での位置変化の速度を求める。例えば、第１の目標の速度をＶ１、第２の目標の速度をＶ２と判定する。このような目標の抽出結果に基づいて、目標抽出器１１２は、表示器２１に画面内の目標の存在位置と、その目標の進行方向の情報を、電気信号ケーブル１９ｂを介して表示器２１に送出する。また、目標抽出器１１２は、予測演算器１１３に対して、目標の存在位置と、その目標の進行方向の情報と、目標の重心位置の軌跡を、目標状態情報として送信する。
【００５６】
表示器２１は、目標抽出器１１２から送出された情報に基づいて、表示器２１の画面内に、目標の存在位置を示す丸などのシンボル、その目標がどの方向に進行中であるのを示す矢印などのシンボルを表示する。また、表示器２１は、画像検出器１１１で処理された目標を含む周囲の映像が、電気信号ケーブル１９ａを介して送信され、その映像を表示する。なお、複数目標がある場合は、丸のシンボルの中に番号表示をしても良い。図１３は、表示器２１のシンボル表示の一例を示す図であって、図中、▲１▼、▲２▼は目標を示している。
【００５７】
なお、目標情報として、予め目標の複数波長の照度比が分かっている場合には、カメラ１６として多波長のカメラを用いることによって、信号処理部４が、誤った物体を目標として抽出する確率を低減することができる。例えば、カメラ１６が２種類の波長帯、λ３、λ４に感度を有する場合、目標データベース１１５に、各種目標毎にλ３、λ４の波長帯における信号強度比の項を追加することにより、信号強度比がロケットや航空機と異なる目標については、目標として検出しなくすることができる。
【００５８】
また、予測演算器１１３は、目標抽出器１１２の出力する目標状態情報に基づいて、目標の未来位置を予測する。目標状態情報として、目標の現在位置と、目標の速度と、目標の軌跡として過去の位置情報が送信される。例えば、図１２の例の場合、目標２０２に関しては、現在位置Ｇ２と速度Ｖ２に基づいて、過去の位置ＯＧ２と現在位置Ｇ２とを繋ぐ軌跡が直線であるので、Ｔ秒後の未来位置をＭＧ２として算出する（ＭＧ２の位置座標＝Ｇ２の位置座標＋速度ベクトルＶ２×Ｔ）。なお、算出に当たっては、加速度を用いても良いし、軌跡が曲線である場合は、その曲線の延長上の位置を、現在位置と現在速度に基づいて予測しても良い。予測演算器１１３は、予測した未来位置を制御器１０４に送信する。
【００５９】
制御器１０４は、複数のレーザ開口部１５の覆域を足し合わせて構成される全周開口面内において、複数のレーザ開口部１５の中から、目標の未来位置がレーザ光照射領域内に入るレーザ開口部１５を選択する。この際、選択したレーザ開口部１５と光ファイバ１３ｂが接続されるように、光スイッチ１２の入出力ポート５２を選択するための出力ポートの指定情報をスイッチ選択器１０３に送出する。スイッチ選択器１０３は、選択された出力ポートの指定情報に基づいて、接続を切替えるための切替え信号を光スイッチ１２に送出し、光スイッチ１２は接続の切替え動作を行う。また、選択されたレーザ開口部１５において、レーザ出力部６０によって偏向されるレーザ光の光軸（指向方向）が目標の未来位置の存在する方向を向くように、レーザ出力部６０の指向方向を設定する。この設定では、目標の未来位置を画面内に有するカメラ１６に対応して、レーザ開口部１５内のレーザ出力部６０を選択する。この際、カメラ１６の画角に対応するレーザ出力部６０の指向方向を、予め規定しておく。
【００６０】
例えば、カメラ１６の画角内に、そのままレーザ出力部６０の偏向角度θｍが入るように設定しておけば好適である。この場合、レーザ出力部６０の偏向角度θｍを、目標の未来位置方向の画角θｇに設定し、制御器１０４にこの設定された偏向角度θｍを送信する。制御器１０４では、レーザ出力部６０の偏向角度θｍに基づいて、偏向角度θｍを所定の角度範囲内（図５の例では１５°）に含むフェルール６３が選択されるように、対応する光スイッチ６１の出力ポートを設定する。また、基準軸Ｂ０に対するフェルール６３の角度と、所望の偏向角度θｍとの角度差に基づいて、角度差を０にするように、ウエッジプリズム６６ａ、６６ｂの回転角を設定する。制御器１０４は、スイッチ選択器１０３に対して、選択した出力ポートの指定情報を送出する。スイッチ選択器１０３は、出力ポートの指定情報に基づいて、接続を切替えるための切替え信号を光スイッチ６１に送出し、光スイッチ６１は接続の切替え動作を行う。また、制御器１０４は、ウエッジプリズム６６ａ、６６ｂを回転駆動するアクチュエータに対して、回転角情報を送出する。ウエッジプリズム６６ａ、６６ｂは、これに基づいて回転角が回転角情報で設定される角度になるように角度調整を行う。
【００６１】
また、制御器１０４は、スイッチ選択器１０３が出力ポートの指定情報に基づいて、光スイッチ１２および光スイッチ６１が確実に所望の接続に切り替わったか否かをモニタし、モニタの結果、所望の接続に切り替わっていなければ、表示器２１にアラーム信号１９を発出する。表示器２１はこのアラーム信号１９に基づいて、動作不良を示す警告情報として、例えば「動作不良」の文字を表示する。
【００６２】
測距器１０２は、レーザ受信器１１から送信される受信データ信号Ｓｉの遷移点間の時間に基づいて、レーザ開口部１５がレーザ光を出射した時刻から、目標で反射したレーザ光がレーザ開口部１５に入射する時刻までの差を計測し、その値に光速の２分の１を掛けることで、目標と分散開口部２との間の距離Ｄを上述の式（２）により算出することができる。
【００６３】
また、レーザ受信器１１から送信される受信データ信号Ｓｉの各遷移点における周波数と、レーザ送信器１０に対して送出する変調信号Ｓｏの最大周波数から上述の式（３）に基づいて、分散開口部２に対する目標の速度を求めることができる。
【００６４】
図１４は、光スイッチ１２および光スイッチ６１の構成例を示す図である。図１４（ａ）、（ｂ）において、１２０および６００はマイクロミラーであって、下部に設けられた図示しない圧電素子のようなマイクロアクチュエータによって上下させることにより、反射方向を変化させる。例えば、光スイッチ１２の構成例を示す図１４（ａ）において、入出力ポート５１を入出力ポート５２ｆに接続する場合は、ミラー１２０ａとミラー１２０ｂを持ち上げることによって、入出力ポート５１から出力されたレーザ光は入出力ポート５２ｆから出力される。また、光スイッチ６１の構成例を示す図１４（ｂ）において、入出力ポート６１ａを入出力ポート６１ｈに接続する場合は、ミラー６００ａとミラー６００ｂを持ち上げることによって、入出力ポート６１ａから出力されたレーザ光は入出力ポート６１ｈから出力される。なお、通常状態では、全てのミラーが下がった状態になっている。このミラー１２０、およびミラー６００の動作は、スイッチ選択器１０３によって上下動作が制御される。
【００６５】
このように構成されたレーザ装置１においては、レーザ光を短時間に所望の方向に出射することができる。例えば、レーザ光の送信方向の制御に、従来技術であるジンバルを用いた場合には、ジンバルの機械的な駆動に時間がかかるため、所望の方向にレーザ光を向けるのに秒単位の時間を要する。これに対して、レーザ開口部１５を分散配置したこの実施の形態１によるレーザ装置では、その１００分の１程度の時間でレーザ光を所望の方向に精度良く指向させることができる。また、レーザ光を指向させるための機械的な駆動部分は、ウエッジプリズム６３ａ、６３ｂ部や、鏡面を微小変位させる光スイッチに限定され、小型に構成することが可能であって、その駆動部分が少なくなるため、装置のメンテナンスも容易になる。また、駆動制御に関わる信号処理の負荷を低減することもできる。
【００６６】
また、目標と分散開口部２との位置関係が変わらない場合には、カメラ１６及び信号処理部４の追尾機能が無くても、目標にレーザ光を照射できると共に、目標からのレーザ光を受信できる。
【００６７】
この実施の形態によれば、レーザ送信器１０と、一端と他端の間でレーザ光を伝送する複数の光ファイバ１４と、レーザ送信器１０と複数の光ファイバ１４の一端との接続を切替える光スイッチ１２と、複数の光ファイバ１４の他端側に夫々結合され、光ファイバ１４を伝送されたレーザ光を外部空間に出力するように、分散配置された複数のレーザ開口部１５とを備えることにより、レーザ出射方向、または入射方向の変更を短時間で行うことのできるレーザ装置を提供することができる。
【００６８】
また、分散開口部２を航空機に分散配置することによって、航空機の周囲３６０°の視野内で所望の方向にレーザ光を出射することができるとともに、分散開口部２の設置高さを、航空機の胴体表面とほぼ同じ高さ、もしくは胴体表面からの突出高さが１０ｍｍ以下となるように設置することができる。これによって、分散開口部２の設置に伴なう空気抵抗が小さくなり、航空機の空力特性に与える影響を抑えることができる。
【００６９】
例えば、特許文献１に開示されるような従来のレーザ装置は、半球形状を有するジンバルの高さが１００ｍｍ〜５００ｍｍにも至り、航空機の胴体表面からの突出高さが１００ｍｍ以上となる。これによって、マッハ数２の最高速度で飛行することの可能な航空機が、ジンバルの突出高さに伴なう空気抵抗の影響によって飛行速度に制限を受け、例えばマッハ数１で飛行せざるを得なくなる。これに対してこの実施の形態では、ジンバルを用いないので、航空機の胴体表面からの突出高さを１０ｍｍ以下とすることができ、空気抵抗を極端に低減することができ、レーザ装置を搭載しても、ほぼ最高速度であるマッハ数２に近い速度で飛行することが可能となる。
【００７０】
また、このように突出高さを低くすることができるため、航空機胴体表面にレーザ装置を設置したことによる、レーザ断面積の変化を小さくすることができ、レーザ装置の搭載に伴なったステルス性の向上を図ることができる。
【００７１】
さらに、ジンバルの姿勢角を駆動制御するためのサーボ系制御用の信号処理器が不要となるため、信号処理器をより小型で簡素なものとすることができる。また、ジンバル自体を用いないために駆動部分が少なくなり、メンテナンスがより容易となる。
【００７２】
また、レーザ光を出射するための開口部分が、ジンバルよりもシンプルな構造で構成されるため、開口部分を小型化することが可能である。
【００７３】
また、ファイバーレーザ発振器（８０ｄ、５００）を用いてレーザ発振できるように構成されているので、狭い空間内にケーブルを配置するかの如く、光ファイバーを狭いスペース内に引き回し、あるいは必要に応じて丸めて配置することができ、配置位置の制約や配置スペース上の制約が緩和される。このため、レーザ開口部の分散配置を可能とすることができる。
【００７４】
ファイバーレーザ発振器とレーザ開口部の間を接続する光伝送経路を、光ファイバーを用いて構成することができるので、ミラーやプリズムなどの反射光学部品を精度高く配置して、光伝送経路を構成する必要がなく、また、反射光学部品の光軸がずれないように、反射光学部品を支持するための強度があって重い構造体を用いなくてもすむ。
【００７５】
また、光ファイバーを用いて光伝送経路が構成されるので、反射光学部品を適宜配置して光伝送経路を構成する際の、反射光学部品間の空間のエアーのクリーン度を上げる必要がない。
【００７６】
また、レーザ発振器からの連続光をＦＭ−ＣＷ変調する光変調器８１と、光変調器８１の出力光を増幅する光増幅器８３と、目標からの反射光と信号発生器（測距器１０２）の出力信号に基いて、受信光を変調する光ミクサを備えて、ＦＭ−ＣＷ変調方式のレーザレーダを構成することができるので、ＦＦＴ（高速フーリエ変換）によるコヒーレント積分が可能となり、小さいパワーのレーザ光で遠方の測距が可能になる。特に、レーザパワーが小さいので、光学系の耐パワー性能、およびレーザ光路上の空間のエアーのクリーン度を低く設計できる。また、パルスレーザを用いた一般に広く利用されているレーザレーダに比べて、光受信器の高速応答が不要となり、高インピーダンスで反射光の受信が可能となる。さらに、ドップラーの同時検出が可能なため、変調した連続光レーザを照射し、時間積分することによって、目標の速度検出が可能となる。
【００７７】
また、レンズ６５の光軸方向を視野内に有するカメラ１６を、夫々のレンズ６５の周辺に複数備えたことにより、カメラ１６の画像中の目標にレーザ光を照射することができる。さらに、レーザ光を照射、受信した方向の状況を画像で確認することができる。
【００７８】
さらにまた、映像中から所望の目標と同じ特徴を持つ目標を探知し、その目標に対してレーザ光を照射できるため、例えば、自機に向かって飛しょうする脅威となる目標（例えばミサイル）をカメラ１６で発見し、レーザ光を照射して目標の飛行を妨害することができる。
【００７９】
実施の形態２．
この実施の形態のレーザ装置では、ファイバレーザを用いてレーザ発振を行い、レーザ送信器１０と波長変換器５２とを接続する第１の光ファイバ系統とは別個に、ファイバレーザと波長変換器とを接続する他の第２の光ファイバ系統を構成している。この実施の形態による波長変換器５２は、ファイバレーザ発振器５００の出力波長λ１と、実施の形態１で示したレーザ送信器１０の出力波長λ２との、二波長を用いて、ＯＰＡを構成する波長変換器５２によってレーザ光の波長変換を行う。
【００８０】
図１５は、実施の形態２によるレーザ装置の構成を示す図である。図において、ファイバレーザ発振器５００の入力端はポンプレーザ発振器５０１に接続されている。ポンプレーザ発振器５０１はファイバレーザ発振器５００の入力端に接続されている。ポンプレーザ発振器５０１は光強度が一定の波長λ０１（＝０．８１μｍ）のポンプ光（励起光）を発生し、ファイバレーザ発振器５００の一端に出力する。ファイバレーザ発振器５００の出力端は光ファイバ３００の一端に接続され、光ファイバ３００の他端は光スイッチ２００の入力ポート２０１ａに接続されており、ファイバレーザ発振器５００は波長λ２（＝１．０６μｍ）のレーザ光を出力する。
【００８１】
また、レーザ送信器１０の出力端は光ファイバ１３ａの一端に接続されて、光ファイバ１３ａの他端は光サーキュレータ１７の入出力ポートに接続されている。レーザ送信器１０は上述したように、ファイバーレーザ発振器８０ｄを有しており、波長λ２（＝１．５５μｍ）のレーザ光を出力する。レーザ受信器１１は光ファイバ１３ｃを介して光サーキュレータ１７の出力ポートに接続されている。光ファイバ１３ｂの一端は光サーキュレータ１７の入出力ポートに接続され、光ファイバ１３ｂの他端は光スイッチ２００の入出力ポート２０１ｂに接続されている。光スイッチ２００の入出力ポート２０２（２０２ａ乃至２０２ｆ）、２０３（２０３ａ乃至２０３ｆ）は、光ファイバ４００（４００ａ乃至４００ｆ）、１４（１４ａ乃至１４ｆ）の一端に夫々接続されている。光ファイバ４００（４００ａ乃至４００ｆ）、１４（１４ａ乃至１４ｆ）の他端は、波長変換器５２（５２ａ乃至５２ｆ）に接続されている。波長変換器５２（５２ａ乃至５２ｆ）に設けられた光ファイバ６７は、レーザ出力部６０（６０ａ乃至６０ｆ）に接続されている。
【００８２】
この実施の形態によるレーザ装置は以上のように構成され、次のように動作する。
図１５に示したファイバレーザ発振器５００や、図７に示したファイバレーザ発振器８０ｄは、誘導放出効果を活性化させる活性物質を含む希土類ドープファイバレーザや、誘導放出用光ファイバに直列に接続されて非線形効果を活性化させる活性物質を含むラマンファイバレーザなどが用いられる。ファイバレーザは両端に一対の反射手段を備えている。この反射手段は、発振する光を反射するミラーやファイバグレーティングが用いられ、ファイバレーザを挟んでファブリ・ペロー共振器を構成している。
【００８３】
希土類ドープファイバレーザは、Ｎｄ、Ｈｏ、Ｅｒ、Ｔｍ、Ｙｂ等の希土類元素が石英系、フッ化物系、リン酸系等の光ファイバの中心をなすコアにドープされて構成されている。この例では、ファイバ−レーザ発振器５００の励起光が０．８１μｍであるので、希土類元素としてはＮｄを用いている。また、ファイバ−レーザ発振器８０ｄの励起光が０．９８μｍであるので、希土類元素としてはＥｒを用いている。これらの励起光は、反射手段を介して希土類ドープファイバに入力される。そして、励起光が希土類ドープファイバのコアを通過する際に、コアにドープされた希土類元素の最外殻電子を励起して反転分布の状態とし、自然放出光が放出される。そして、誘導放出効果によって自然放出光が一対の反射手段の間を往復しながら増幅され、ついには発振状態となる。発振状態の光（レーザ光）の一部が反射手段を透過して、所望の波長のレーザ光として出力される。
【００８４】
なお、ラマンファイバレーザを用いる場合は、石英系の光ファイバと、この光ファイバを挟んで配置される一対の反射手段とを備える。このラマンファイバレーザにおいては、希土類ドープファイバと同様に、ファイバグレーティングのような一対の反射手段で光ファイバを挟んでファブリ・ペロー共振器を構成している。ラマンファイバレーザにおいては、高パワーの励起光が反射手段を介してファイバレーザの一端から入力される。ラマンファイバレーザにおいては、高パワーの励起光が光ファイバを通過する際に、光と光学フォトン（格子振動）との相互作用において、励起光の一部は長波長側にシフトし、自然ラマン散乱光が得られる。そして、誘導ラマン散乱（非線形効果）によって、自然ラマン散乱光が一対の反射手段の間を往復しながら増幅され、ついには発振状態となる。そして、発振状態の光（レーザ光）の一部が反射手段を透過し、所望の波長のレーザ光として出力される。
【００８５】
光スイッチ２００は、入力ポート２０１ａがファイバレーザ発振器５００の一端に接続される。また、入力ポート２０１ｂが光ファイバ１３ｂの他端に接続される。光スイッチ２００の入出力ポート２０２（２０２ａ乃至２０２ｆ）、２０３（２０３ａ乃至２０３ｆ）は、波長変換器５２（５２ａ乃至５２ｆ）の一端に接続される。また、波長変換器５２（５２ａ乃至５２ｆ）の他端はレーザ出力部６０（６０ａ乃至６０ｆ）に接続される。光スイッチ２００は、入出力ポート２０１ａを、入出力ポート２０２（２０２ａ乃至２０２ｆ）に接続する。また、光スイッチ２００は、入出力ポート２０１ｂを、入出力ポート２０３（２０３ａ乃至２０３ｆ）に接続する。
【００８６】
かくして、光ファイバ８０ｃ、８３ａ、１３ａ、１３ｂ、および光ファイバ２０３は、第１の光ファイバ系統を構成する。また、ファイバレーザ発振器５００、光ファイバ３００、および光ファイバ２０２は、第２の光ファイバ系統を構成する。第１の光ファイバ系統中の光ファイバは、波長１．５５μｍの第１のレーザ光を伝送するときの損失が少なくなるように、波長１．５μｍ帯の光信号を伝送するに適したシングルモードファイバが用いられる。また、第２の光ファイバ系統中の光ファイバは、波長１．０６μｍの第２のレーザ光を伝送するときの損失が少なくなるように、波長１μｍ帯の光信号を伝送するに適したシングルモードファイバが用いられる。これらのシングルモードファイバは、比較的入手性が良い。
【００８７】
第１の光ファイバ系統を伝送された第１のレーザ光は、図６に示した波長変換器５２（５２ａ乃至５２ｆ）と同様、レンズ７１に入力される。また同時に、第２の光ファイバ系統を伝送された第２のレーザ光は、波長変換器５２のレンズ７１に入力される。波長変換器５２では、レンズ７１で集光された第１、第２のレーザ光が非線形光学部７０に入力されて、パラメトリック増幅作用によって、増幅された第１のレーザ光と、波長変換された第３のレーザ光を光ファイバ６７に出力する。第３のレーザ光として、例えば波長３μｍのレーザ光が出力される。
【００８８】
ここで、波長３μｍの第３のレーザ光は、例えば他のレーザ装置の電磁波受信センサの動作を妨害するために用いることができる。例えば、目標が飛しょう体であって、飛しょう体の先端に赤外線を感知するシーカが設けられた場合を想定する。この場合、レーザ開口部１５から、シーカの赤外線の検出波長（例えば３μｍ帯の）と一致するとともに、シーカの検出器の受光感度を飽和させる程度のレベルの高いレーザ光を照射する。この際、ファイバレーザ発振器５００を用いることによって、第３のレーザ光の出力パワーを適度なレベルまで増加させることができる。これによって、この実施の形態のレーザ装置は、飛しょう体の妨害装置として動作させることができる。
【００８９】
飛しょう体のシーカをこのような妨害装置として用いる場合は、第３のレーザ光が目標で反射されて戻ってくることは想定されておらず、１．５μｍ帯の第１のレーザ光のみ目標から反射された反射光を受光できれば良い。
【００９０】
なお、レーザ出力部６０を構成する光ファイバ６２には、１．５μｍ帯と３μｍ帯のレーザ光を高効率で伝送する光ファイバを使用する。一般に１．５μｍと３μｍ帯の両方を透過する光ファイバは、通信用に用いられている１．５μｍ帯の光ファイバと比較すると透過率は低いが、光ファイバ６２の長さは短く、問題にはならない。これによって、第１の光ファイバ系統からレーザ出力部６０の開口面（レンズ６５）に至るまでの経路において、１．５μｍ帯の第１のレーザ光と３μｍ帯の第３のレーザ光をレーザ出力部６０まで損失なく伝送することができる。また、１μｍ帯の第２のレーザ光はファイバレーザ発振器５００から第２の光ファイバ系統を用いて伝送されるため、レーザ出力部６０の波長変換器５２までの間を、１μｍ帯の第２のレーザ光を用いて損失なく伝送することができる。この場合、光ファイバ６７には、波長変換器５２で変換された３μｍ帯の波長のレーザ光が通過するが、これについては多少の伝送損失があっても構わない。
【００９１】
このような構成によって、伝送波長帯に合わせた光ファイバを用いてレーザ光を伝送し、レーザ出力部の開口面の直前に波長変換器を配置して、レーザ光の波長を変換するため、損失の少ないレーザ光の伝送と波長変換が可能となる。
【００９２】
この実施の形態によるレーザ装置では、入力されるレーザ光から波長の異なるレーザ光を生成し、生成したレーザ光を夫々のレーザ開口部１５に出力する波長変換器５２を備えたことにより、複数種類の波長のレーザ光を目標に照射できるため、レーザ光を照射する目標が持つセンサの種類に応じて、目標に照射するレーザ光を使い分けることができる。
【００９３】
また、波長の異なる第１、第２の波長のレーザ光を発生するファイバーレーザ発振器８０ｄ、およびファイバーレーザ発振器５００を備えて、第１、第２の波長に夫々対応してレーザ光を伝送する一対の光ファイバ対（４００、１４）を複数対備えることにより、夫々の光ファイバ対（４００、１４）毎に接続され、入力される第１、第２の波長のレーザ光に基づいて波長の異なる第３の波長のレーザ光を生成し、生成された第３の波長のレーザ光をレーザ開口部１５に出力する複数の波長変換器５２を備えることにより、光スイッチ１２は、ファイバーレーザ発振器８０ｄ、および５００と、複数の光ファイバ対（４００、１４）との接続を切替えるように構成しているので、同時に２目標に対してレーザ光を照射することができる。また、冗長系を持たせることによって、第１、第２のレーザ発振器のいずれか一方が故障した場合であっても、他方のレーザ発振器でレーザ照射を続行することができる。
【００９４】
実施の形態３．
実施の形態１では、ウエッジプリズム６６ａ、６６ｂと、球の曲率中心を向くように離散的に配置されたフェルール６３を用いて、レーザ出力部６０（６０ａ乃至６０ｆ）を構成していた。しかし、レーザ出力部としては、９０°×９０°の立体角を包絡するようにレーザの指向角度を調整するものであれば、他の機構を用いても良い。
【００９５】
この実施の形態では、例えば、９０°×９０°の角度範囲のみ駆動するような小型のジンバルにレンズ６５を配置して、レンズ６５に対してレーザ光を導くような光学系を構成する。これによって、比較的簡単な構成でレーザ光の指向方向を偏向させる光学系を実現することができる。このようなジンバルとしては、特許文献１に記載されるような大型のジンバルの可動角を制限して、小型のジンバルを構成すればよい。
【００９６】
実施の形態４．
この実施の形態４では、レーザ送信器１０から光通信用の変調信号Ｓｏを出力しても良い。例えば、光ファイバ通信で用いられているようなＮＲＺ（Ｎｏｎ Ｒｅｔｕｒｎ ｔｏ Ｚｅｒｏ）信号をレーザ送信器１０から出力しても良い。レーザ送信器１０は、レーザ開口部１５からレーザ光を照射し、レーザ光の照射方向に配置された他のレーザ装置でレーザ光を受光する。また、レーザ受信器１１は、送信するレーザ光の波長帯域がレーザ装置のレーザ受信器１１の受信波長帯と一致する場合には、レーザ装置を光通信用の受信器として機能させる。
【００９７】
実施の形態５．
実施の形態１では、航空機にレーザ装置を搭載した例について説明した。しかし、実施の形態１で説明したようなレーザ装置は、他の移動体に搭載しても良い。例えば、陸上を移動する車両、または水上を移動する艦船、または空中を飛行する航空機、または宇宙空間を飛しょうする人工衛星などで構成しても良い。この場合には、レーザ装置を容易に移動できる他、移動体にレーザ装置の機能を付加することができる。また、移動体の進行方向に視野を持つカメラの分解能を、他の方向に視野をもつカメラの分解能よりも高くしてよく、この場合には、進行方向前方の障害物や目標を遠方で発見しやすくできる。
【００９８】
【発明の効果】
この発明によれば、以上説明したように、レーザ出射方向、または入射方向の変更を短時間で行うことのできるレーザ装置を提供することができる。
【図面の簡単な説明】
【図１】この発明の実施の形態１によるレーザ装置を航空機へ搭載した状態を示す図である。
【図２】この発明の実施の形態１によるレーザ装置を航空機に搭載した場合の開口面の配置を示す図である。
【図３】この発明の実施の形態１によるレーザ装置の構成を説明する図である。
【図４】この発明の実施の形態１によるレーザ装置の分散開口部の外観を示す斜視図である。
【図５】この発明の実施の形態１によるレーザ装置のレーザ開口部の構成を示す図である。
【図６】この発明の実施の形態１によるレーザ装置の波長変換器の構成を示す図である。
【図７】この発明の実施の形態１によるレーザ装置のレーザ送受信器の構成を示す図である。
【図８】この発明の実施の形態１によるレーザ装置の光ミクサの出力するビート光の波形を説明する図である。
【図９】この発明の実施の形態１によるレーザ装置の信号処理部の構成を示す図である。
【図１０】この発明の実施の形態１によるレーザ装置の画像処理器の構成を示す図である。
【図１１】この発明の実施の形態１によるレーザ装置の目標情報データベースの構成を示す図である。
【図１２】この発明の実施の形態１による目標画像の例を示す図である。
【図１３】この発明の実施の形態１による表示器のシンボル表示を示す図である。
【図１４】この発明の実施の形態１による光スイッチの一例を示す図である。
【図１５】この発明の実施の形態２による光スイッチと波長変換器の構成を示す図である。
【符号の説明】
１ レーザ装置、２ 分散開口部、３ レーザ送受信器、４ 信号処理部、５電源部、１０ レーザ発信器、１１ レーザ受信器、１２ 光スイッチ、１３ａ，１３ｂ 光ファイバ、１４ａ，１４ｂ 光ファイバ、１５ レーザ開口部、１６ カメラ、５２ 波長変換器、５３ 光学窓、５４ 光学窓、５５ 上蓋、６０ レーザ出力部、６１ 光スイッチ、６２ 光ファイバ、６３ フェルール（光ファイバ端末）、６５ レンズ、６６ａ，６６ｂ ウエッジプリズム、８０レーザ発振器、８１ 光変調器、８２ ドライバ回路、８３ 光増幅器、９２光ミクサ、１０１ 画像処理器、１０３ スイッチ選択器、１０４ 制御器、２００ 光スイッチ、５００ ファイバレーザ。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a laser device that emits laser light output from a laser light source toward an external space or receives laser light received from an external space.
[0002]
[Prior art]
Conventionally, as a laser device for measuring a distance by outputting laser light to an external space, an imaging device and a laser distance measuring device for measuring a distance are provided on a gimbal, and the distance between the position of the target object in the image and the image center is provided. An image processing device that calculates an error angle of the image, a tracking calculation device that outputs a gimbal control signal based on the error angle, and a gimbal control device that drives and controls the gimbal according to the gimbal control signal have been proposed (for example, Patent Document 1). reference).
[0003]
[Patent Document 1]
JP-A-10-132935
[0004]
[Problems to be solved by the invention]
The conventional laser apparatus controls the direction of the laser range finder mounted on the gimbal to drive the laser beam to the external space or the laser beam incident direction from the external space in a desired direction. Oriented.
[0005]
However, when driving control is performed using a gimbal, there is a problem that a time delay occurs in driving the gimbal until the gimbal pointing direction is set to a desired direction.
[0006]
The present invention has been made to solve such a problem, and an object of the present invention is to obtain a laser device that directs the emitting direction or incident direction of laser light in a desired direction in a shorter time.
[0007]
[Means for Solving the Problems]
The laser device according to the present invention switches a connection between a laser light source that outputs laser light, a plurality of optical fibers that transmit laser light between one end and the other end, and the laser light source and one end of the plurality of optical fibers. An optical switch, and a plurality of lenses coupled to the other ends of the plurality of optical fibers and outputting laser light transmitted through the optical fibers to an external space, and the optical axes of the plurality of lenses are mutually connected. They are arranged with different directivity directions.
[0008]
The laser device according to the present invention includes a laser receiver that receives laser light, a plurality of optical fibers that transmit laser light between one end and the other end, and one end of the laser receiver and the plurality of optical fibers. And a plurality of lenses coupled to the other ends of the plurality of optical fibers and receiving incident light from an external space, and the optical axes of the plurality of lenses are directed to each other. Are arranged differently.
[0009]
A laser device according to the present invention includes a laser oscillator that outputs continuous light, a signal generator that generates a modulation signal, and an optical modulator that modulates continuous light from the laser oscillator based on an output signal of the signal generator. An optical amplifier that amplifies the output light of the optical modulator, an optical mixer that modulates the received light based on the modulation signal, and a laser beam transmitted between one end and the other end And an optical switch connected to one end of each of the plurality of optical fibers, and a laser beam output from the optical amplifier is distributed to the optical switch and reflected from a target output from the optical switch. An optical circulator that distributes light to the optical mixer, an optical receiver that outputs a reception data signal based on an output signal of the optical mixer, and the other ends of the plurality of optical fibers are coupled to each other in an external space. A plurality of lenses that output laser light or receive incident light from an external space, and the optical switch switches connection between the optical circulator and one end of the plurality of optical fibers, and the plurality of lenses These optical axes are arranged so that their directivity directions are different from each other.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1 FIG.
FIG. 1 is a diagram showing a configuration of a laser apparatus according to Embodiment 1 of the present invention, and FIG. 2 is a diagram showing a field of view of an aircraft equipped with the laser apparatus.
In FIG. 1, a laser device 1 includes a dispersion opening 2 (2 a to 2 f), a laser transmission / reception unit 3, a signal processing unit 4, and a power supply unit 5, and is mounted on an aircraft 6. A plurality of, for example, six dispersion openings 2 are arranged on the surface of the fuselage 7 of the aircraft 6. In the example shown in the figure, one dispersion opening 2 a is disposed facing the front surface of the body 7, one dispersion opening 2 b is disposed facing the rear surface of the body 7, and is dispersed toward the right upper surface of the body 7. One opening 2c is arranged, one dispersion opening 2d is arranged facing the upper left surface of the fuselage 7, one dispersion opening 2e is arranged facing the lower right surface of the fuselage 7, and the lower left surface of the fuselage 7 One dispersive opening 2f is arranged so as to face. As will be described later, the dispersion opening portion 2 forms an opening for input / output of laser light for emitting laser light to the external space or receiving laser light incident from the external space.
[0011]
The laser transmission / reception unit 3, the signal processing unit 4, and the power supply unit 5 are arranged adjacent to each other in the center of the fuselage 7 of the aircraft 6 (for example, behind the cockpit), and each of them is composed of at least one unit. Yes. Each dispersion opening 2 and the laser transmitting / receiving unit 3 are connected by an optical fiber to be described later. The laser transmitting / receiving unit 3, the signal processing unit 4, and the power supply unit 5 are connected by an electric signal cable described later.
[0012]
FIG. 2A shows an example of the arrangement of the opening surface when the field of view of the aircraft 6 is divided into 90 ° × 90 ° angles in the up / down and front / rear directions to form the opening surface of the dispersion opening 2. That is, the field of view of the aircraft is expressed by six surfaces (front surface, rear surface, right upper surface, left upper surface, right lower surface, left lower surface) constituting a cube. Here, the dispersive openings 2 are arranged so that the respective open faces face in any one of the six faces, and all (six) spread openings 2 cover all six faces. Are distributed on the surface of the fuselage 7 of the aircraft. As a result, the laser light is output so as to cover the entire circumferential surface (the entire spherical surface) around the aircraft 6 by joining all the six opening surfaces of the distributed aperture portions 2 (2a to 2f) that are dispersedly arranged. Can do.
[0013]
FIG. 2B is a diagram showing the arrangement of the opening surfaces of the dispersion openings 2 when FIG. 2A is viewed from the I direction, that is, from the front of the aircraft 6. As shown in the figure, the dispersion openings 2c to 2f are arranged at 90 ° intervals so that the right upper surface, left upper surface, right lower surface, and left lower surface of the field of view of the aircraft 6 are open surfaces.
[0014]
FIG. 3 is a block diagram showing the configuration of the laser apparatus according to Embodiment 1 of the present invention. In the figure, the same reference numerals as those in FIG. In the figure, the laser transmitting / receiving unit 3 includes a laser transmitter 10 and a laser receiver 11 which are laser light sources.
[0015]
The light output end of the laser transmitter 10 is connected to one end of the optical fiber 13a. The laser transmitter 10 receives the modulation signal So from the signal processing unit 4 via the electric signal cable 20. The laser transmitter 10 outputs a laser beam modulated according to the modulation signal So and inputs the laser beam to the optical fiber 13a. The other end of the optical fiber 13 a is connected to the input port of the optical circulator 17. The input / output port of the optical circulator 17 is connected to one end of the optical fiber 13 b, and the other end of the optical fiber 13 b is connected to the input / output port 51 of the optical switch 12. The output port of the optical circulator 17 is connected to one end of the optical fiber 13 c, and the other end of the optical fiber 13 c is connected to the optical input end of the laser receiver 11. The optical circulator 17 outputs the laser light input to the input port to the input / output port, and outputs the laser light input to the input / output port to the output port.
[0016]
The laser receiver 11 receives the laser light transmitted through the optical fiber 13c, and after intensity-modulating the laser light again by the modulation signal So input from the signal processing unit 4 via the electric signal cable 20. The laser beam is photoelectrically converted to output a reception data signal Si. The output received data signal Si is input to the signal processing unit 4 via the electric signal cable 20. The input / output port 52 (52a, 52b, 52c, 52d, 52e, 52f) of the optical switch 12 is connected to one end of the optical fiber 14 (14a, 14b, 14c, 14d, 14e, 14f). The other end of the optical fiber 14 is connected to a laser opening 15 provided in the dispersion opening 2. The optical switch 12 is connected to the signal processing unit 4 via the electric signal cable 20. Further, here, the modulation signal So is described as being input to the laser receiver 11, but a signal obtained by delaying the modulation signal So may be input to the laser receiver. The electric signal cable 20 is composed of a plurality of signal cables so that the modulation signal So, the reception data signal Si, and the switching signal (described later) can be transmitted independently.
[0017]
The dispersion opening 2 includes a camera 16 adjacent to the laser opening 15. The laser opening 2 and the camera 16 are connected to the dispersion opening side terminal of the electric signal cable 18, and the other terminal (signal processing unit side terminal) of the electric signal cable 18 is connected to the signal processing unit 4. The signal processing unit 4 is connected to the display device 21 via the electric signal cable 19. The power supply unit 5 supplies power to the signal processing unit 4, the laser transmitter 10, the laser receiver 11, and the display 21. Although not shown, the power supply unit 5 is connected to the camera 16 of the laser aperture 15 and an optical system to be described later, and supplies necessary power to each of them. At this time, as the optical system, power is supplied to the actuator that drives the wedge prisms (66a, 66b) and the microactuator that drives the optical switches 12, 61, respectively.
[0018]
The laser openings 15 are mounted on the dispersion opening 2 and are distributed on the surface of the body 7. The laser opening 15 emits laser light to an external space around the laser device or makes laser light incident from an external space around the laser device. The laser aperture 15 is composed of an optical system including a lens to be described later, and the optical axis of the optical system faces a different direction for each laser aperture 15.
[0019]
In the example shown in the figure, the optical axis direction is shown at intervals of 36 ° in order to show that the angle of the optical axis of the laser aperture 15 is different, but as described above, in view of the example of FIG. The respective optical axis directions are arranged at intervals of 90 °.
[0020]
Laser light emitted from the laser transmitter 10 is transmitted through the optical fibers 13 a and 13 b and input to the optical switch 12. The optical switch 12 selects any one of the input / output ports 52a to 52f and inputs laser light to one end of the corresponding optical fiber 14 (any one of 14a to 14f) of each input / output port. The other end of the optical fiber 14 transmits the input laser light to the dispersion aperture 2 (any of 2a to 2f), and the transmitted laser light is emitted from the dispersion aperture 2 to the surrounding external space.
[0021]
When laser light emitted from the dispersion opening 2 to the external space is irradiated to a specific external object, the laser light is reflected by the surface (reflection point) of the object, and a part of the reflected light is dispersed. Returning to the opening 2 again, the light enters the opening surface of the dispersion opening 2. The laser light incident on the dispersion aperture 2 is transmitted in order through the optical fibers 14 a to 14 f, the optical switch 12, the optical fiber 13 b, the optical circulator 17, and the optical fiber 13 c, and enters the laser receiver 11.
[0022]
The camera 16 receives electromagnetic waves (for example, infrared rays, ultraviolet rays, or visible rays) from the external space around the laser device 1, converts them into image signals, and outputs them. The visual axes of the respective cameras 16 are directed in different directions. Considering the example of FIG. 2, when the angle of view of the camera 16 is 90 ° × 90 ° and the visual axes are directed in six directions (cubic) orthogonal to each other, six cameras arranged in a distributed manner are used. A view of the entire circumference can be obtained. Further, if the angle of view of each camera 16 is slightly increased and installed so that the ends of the angles of view of the respective cameras 16 overlap with each other, even if the installation angle of the camera 16 is deviated, the field of view of the entire circumference is displayed. Can be obtained. The optical axis of the laser aperture 15 is in a positional relationship that falls within the field of view of the camera 16.
[0023]
FIG. 4A is a perspective view showing a detailed configuration of the dispersion opening 2.
In the figure, a wavelength converter 52, a laser aperture 15, and a camera 16 are accommodated in a cylindrical container 51. An optical window 53 is provided on the upper lid 55 that closes the cylindrical end surface of the container 51 so as to face the laser opening 15. The upper lid 55 is provided with an optical window 54 facing the camera 16. By attaching the upper lid 55 to the end surface of the container 51, the upper lid 55 can suppress the thickness from the bottom surface of the container 51 to 10 mm or less. The height can be set so that it is substantially the same as the fuselage surface of the aircraft, or the protruding height from the fuselage surface is 10 mm or less.
[0024]
The wavelength converter 52 is disposed on the bottom surface of the container 51, and the optical fiber 14 and the electric signal cable 18 are connected to each other. A laser aperture 15 is connected to the upper portion of the wavelength converter 52. The laser opening 15 is arranged so that the reference axis B 0 of the laser opening 15 coincides with the cylindrical axis of the container 51. The camera 16 is disposed in the vicinity of the laser opening 15 and is sandwiched between the inner cylinder of the container 51 and the outer cylinder of the laser opening 15. The laser opening 15 and the camera 16 are accommodated in the container 51 and fixed to a common structure. With this configuration, the reference axis of the laser aperture 15 and the visual axis of the camera 10 can be accurately aligned, and the amount of deviation between the two axes in a vibration environment or a temperature environment can be reduced.
[0025]
FIG. 4B shows the internal configuration of the camera 16 in FIG.
The camera 16 includes two cameras 16a and 16b having different wavelengths. The electromagnetic field received from the optical window 54 is separated by the separation plate 300 into an electromagnetic field sensitive to the camera 16a and an electromagnetic field sensitive to the camera 16b. An electromagnetic field sensitive to the camera 16a passes through the separation plate 300 and enters the camera 16a. The electromagnetic field sensitive to the camera 16b is reflected by the separation plate 300, is reflected by the mirror 301, and then enters the camera 16b. Thereby, the camera 16 can acquire images of two different wavelengths. Needless to say, a plurality of cameras having different wavelengths may be used as the camera 16 or a single camera may be used.
[0026]
The camera 16 is preferably configured with a sensitivity in the infrared region. Accordingly, a thermal image of the laser beam emission destination or the laser beam incidence destination can be acquired, and the target that generates heat can be easily extracted. Further, if the camera 16 has sensitivity in the wavelength band of the laser beam, the brightness of the region irradiated with the laser beam is increased, so that the image captured by the camera 16 becomes clearer. In particular, in this case, it can be operated as a laser illuminator. In addition, by using a plurality of types of cameras with different wavelengths as the camera 16, it is possible to obtain illuminance ratio information of a plurality of wavelengths from an image captured by the camera 16. The illuminance ratio information can be obtained, for example, by A / B, which is the ratio between the illuminance A of the image captured by the camera 16a and the illuminance B of the image captured by the camera 16b.
[0027]
FIG. 5 is a diagram showing a more detailed configuration of the laser aperture 15. In the figure, for the sake of simplicity, the ferrule holding member 64 and the wedge prisms 66a and 66b are shown in cross section. In the figure, the laser aperture 15 is provided with a wavelength converter 52, an optical switch 61 connected to the wavelength converter 52, and a laser output unit 60 connected to the optical switch 61. The laser output unit 60 includes an optical switch 61, an optical fiber 62, a ferrule 63, a ferrule holding member 64, a lens 65, and wedge prisms 66a and 66b. The lens 65 and the wedge prisms 66a and 66b constitute an optical system.
[0028]
One end of the wavelength converter 52 is connected to the other end of the optical fiber 14. The other end of the wavelength converter 52 is connected to one end of the optical fiber 67. The other end of the optical fiber 67 is connected to the input / output port 61a of the optical switch. The input / output ports 61b, 61c, 61d, 61e, 61f, and 61g of the optical switch 61 are connected to one ends of the optical fibers 62a, 62b, 62c, 62d, 62e, 62f, and 62g, respectively. By switching the optical switch 61, one of the ferrules 63 is selected and optically connected to the optical fiber 67. The other ends of the optical fibers 62a, 62b, 62c, 62d, 62e, 62f, and 62g are connected to a ferrule (optical fiber terminal) 63, respectively. The axis of the ferrule 63 is fixed to the ferrule holding member 64. The ferrule holding member 64 has a curved surface shape forming a partial spherical surface, and the center (or principal point) of the lens 65 is arranged at the center of curvature of the partial spherical surface of the ferrule holding member 64. The ferrule 63 is arranged on the partial spherical surface of the ferrule holding member 64 so that a straight line connecting the axis of the ferrule 63 and the center of curvature of the ferrule holding member 64 is arranged at a predetermined angle interval θf.
[0029]
In the example of FIG. 5, the angle formed by the ferrule 63a and the ferrule 63b is the same as the angle formed by the ferrule 63b and the ferrule 63c. Moreover, in the example of the same figure, seven ferrules are arrange | positioned in the cross section which passes along the center of curvature of the partial curved surface of the ferrule holding member 64, and each ferrule is arrange | positioned at intervals of 15 degrees. That is, the angle formed by the ferrule 63a and the ferrule 63g at both ends in the same section with a straight line connecting the centers of curvature is 90 ° or more. Further, the laser light output from each ferrule 63 is output at intervals of 15 °.
[0030]
The lens 65 may be a single lens or a double lens, and an optimum lens may be selected as appropriate depending on the lens design. The lens 65 includes an objective lens. The curved surface shape of the ferrule holding member 64 may be a quadratic curved surface shape such as a parabola or an ellipse. In this case, the center (or principal point) of the lens 65 is arranged at the focal point of the quadric surface.
[0031]
Each of the wedge prisms 66a and 66b has an elliptical inclined surface and a circular flat surface that form an input / output surface for laser light. The slope of the trapezoidal cross section of the wedge prism 66a faces the lens 65, and the trapezoidal cross section planes of the wedge prism 66a and the wedge prism 66b are arranged to face each other. The slope of the trapezoidal cross section of the wedge prism 66 b is disposed so as to face the optical window 53. The wedge prism 66a and the wedge prism 66b are disposed such that the center of the plane coincides with the rotation axis 68, and are supported rotatably around the rotation axis 68 as a rotation center. The rotation angle of the wedge prism 66a and the wedge prism 66b can be adjusted independently by an actuator (not shown). Thus, by adjusting the rotation angles of the wedge prism 66a and the wedge prism 66b, the direction of refraction can be deflected, and the output direction of the laser light relative to the input light can be deflected. Thus, the angle formed by the laser beam output direction (directing direction) with respect to the reference axis B0 of the laser aperture 15 can be set to a desired deflection angle θm.
[0032]
For example, in the example of FIG. 5, a case is considered in which laser light is output from the ferrule 63f selected by the optical switch 61 and the slope of the wedge prism 66a is fixed at the maximum upward tilt angle. In this case, the laser beam is output in a direction parallel to the ferrule 63g when it is arranged in a square shape so that the angle formed by the inclined surface of the wedge prism 66b with respect to the inclined surface of the wedge prism 66a is maximized. When the inclined surface of the wedge prism 66b is arranged in parallel to the inclined surface of the wedge prism 66a, the laser light is output in a direction parallel to the ferrule 63f.
[0033]
Next, consider a case where laser light is output from the ferrule 63b selected by the optical switch 61 and the slope of the wedge prism 66a is fixed at the maximum upward tilt angle. In this case, the laser beam is output in a direction parallel to the ferrule 63a when it is arranged in a square shape so that the angle formed by the inclined surface of the wedge prism 66b with respect to the inclined surface of the wedge prism 66a is maximized. When the inclined surface of the wedge prism 66b is arranged so that the inclined surface of the wedge prism 66b is parallel to the inclined surface of the wedge prism 66a, the laser light is output in a direction parallel to the ferrule 63b.
[0034]
Thus, in the example of FIG. 5, the angle range θd deflected by the wedge prisms 66a and 66b is in the range of 0 ° to ± 15 °. That is, the angle range θd is centered on the deflection angle θm corresponding to the selected ferrule 63 of the optical switch 61 so as to continuously connect at least the angle θf between adjacent ferrules 63 (15 ° in the illustrated example). Fine adjustment of the output direction of the laser beam is possible within this range.
[0035]
Of course, in consideration of manufacturing errors, the angle range θd may be set to a range of 0 ° to 2θf (30 ° in the illustrated example). However, as the angle range θd increases, the diameter of the wedge prism increases. As a result, the apparatus becomes larger, or the angle of inclination of the wedge prism increases and the angle accuracy deteriorates. The technique for deflecting the direction of the laser beam using a wedge prism is normally implemented. However, in combination with the optical switch 61 and the ferrule 63 as in the first embodiment, the laser beam is combined. There is no known thing that changes the direction of direction.
[0036]
FIG. 6 is a diagram illustrating a configuration of the wavelength converter 52. The laser light transmitted through the optical fiber 14 is emitted from the other end surface of the optical fiber 14 and input to the nonlinear optical unit 70 through the lens 71. The nonlinear optical unit 70 constitutes an optical parametric oscillator (OPO) or an optical parametric amplifier (OPA), and performs wavelength conversion. The wavelength-converted laser light (wavelength-converted light) that has passed through the nonlinear optical unit 70 is collected by the condenser lens 72, is incident on one end surface of the optical fiber 67, and is transmitted through the optical fiber 67.
[0037]
When the nonlinear optical unit 70 constitutes an optical parametric oscillator (OPO), the wavelength of the laser light transmitted through the optical fiber is converted, and signal light and idler light having different wavelengths are output. For this reason, the nonlinear optical unit 70 is, for example, LiNbO. ₃ A non-linear crystal such as KTP, whose crystal axis orientation is set so as to satisfy the conditions (phase matching conditions) that the propagation speeds coincide with each wavelength of laser light, signal light, and idler light. One or a plurality of them, or to satisfy the conditions (pseudo phase matching conditions) that the propagation speeds of these crystals match each wavelength of the laser light, signal light, and idler light for each period. PPLN (Periodic PoledLiNbO) in which the axial direction of the crystal is periodically reversed. ₃ ), Or one or more bulk quasi-phase matched nonlinear optical crystals such as PPKTP (Periodic Poled KTP). In particular, PPLN added with MgO is known to be excellent in terms of conversion efficiency and damage resistance, and is suitable here. Needless to say, use of a waveguide-type nonlinear optical crystal instead of a bulk increases the light intensity and provides high conversion efficiency. Then, mirror surfaces are arranged on both ends of the nonlinear optical crystal so as to cause laser resonance at both ends of the nonlinear optical crystal, or reflecting films are formed on both ends of the nonlinear optical crystal. When the nonlinear optical unit 70 constitutes an optical parametric amplifier (OPA), the laser transmitter 10 generates signal light and pump light as two-wavelength laser lights having different wavelengths. The signal light and pump light transmitted through the optical fibers 13a, 13b, and 14 are amplified or wavelength-converted by the nonlinear optical unit 70, and the amplified signal light and the wavelength-converted idler light are output. At this time, each of the optical fibers 13a, 13b, and 14 may be configured by a pair of optical fibers so that the laser light is transmitted by an optical fiber corresponding to each wavelength. This will be described in detail in the second embodiment. Thus, up to the optical fiber 14, the laser beam is transmitted at a wavelength that transmits the inside of the optical fiber 14 with high efficiency, and is converted into a laser beam having a desired wavelength immediately before the laser output unit 60 in the laser opening 15. Therefore, the loss in the optical fiber 14 of the laser light can be suppressed.
[0038]
FIG. 7 is a diagram illustrating the configuration of the laser transmitter 10, the laser receiver 11, and the optical circulator 17. The laser transmitter 10 includes a laser oscillator 80, a modulator 81, a driver circuit 82, and an optical amplifier 83.
The laser oscillator 80 includes a semiconductor laser 80a, a lens 80b, a fiber laser oscillator 80d, and an optical fiber 80c. The semiconductor laser 80a is supplied with a bias current Ib whose current value has been adjusted so that the light output intensity is constant. The semiconductor laser 80a is supplied with this bias current, outputs continuous laser light (excitation light) having a constant light intensity at the wavelength λ02, and is condensed by the lens 80b. The pumping light transmitted through the lens 80b is incident on the fiber laser oscillator 80d to increase the energy state of the rare earth element added in the fiber laser oscillator, and a continuous laser beam (CW laser) having a wavelength λ2 (for example, 1.55 μm). Is output to the optical fiber 80c. Details of the fiber laser transmitter 80d will be described later also in the second embodiment.
Here, a fiber laser with low noise is described as the laser transmitter 80, but a semiconductor laser itself may be used as the laser transmitter 80.
[0039]
The modulator 81 receives the CW laser transmitted through the optical fiber 80c. This input light is transmitted through the optical fiber 80 c and input to the modulator 81. The modulator 81 is configured using, for example, a waveguide type LN modulator. The LN modulator has a waveguide formed by diffusing titanium (Ti) metal on the surface of LiNbO3 (lithium niobate) (LN) crystal. The input light input through the optical fiber 80c passes through the input waveguide 81g, is branched into equal amounts of light by the Y branch 81c, and is output to the waveguide 81a and the waveguide 81b. The light input to these waveguides has its optical phase modulated in accordance with the signal applied from the terminal 81e or 81f to the modulation electrodes provided in the vicinity of the waveguides 81a and 81b. Next, the lights whose optical phases have been modulated are combined by the Y-combining 81d, and become modulated light having a wavelength λ1 that has undergone a change in light intensity due to interference of laser light having different phases, via the output waveguide 81h. It is output to one end of the optical fiber 83a. Here, the LN modulator has been described as the modulator 81, but an acousto-optic light modulator, an electroabsorption semiconductor modulator, or the like is used as a usable optical modulator capable of modulating the laser light intensity. Also good.
[0040]
The driver circuit 82 generates a frequency-modulated modulation voltage signal Vm and a bias signal Vb. The modulator 81 receives the modulation voltage signal Vm output from the driver circuit 82 from the terminal 81e. Further, the modulator 81 receives the bias signal Vb output from the driver circuit 82 from the terminal 81f. The driver circuit 82 is supplied with the modulation signal So and outputs a modulation voltage signal Vm whose amplitude is adjusted by the operation of the differential amplifier.
[0041]
The optical amplifier 83 includes a pump laser oscillator 84, an optical coupler 83b, and an optical fiber amplifier 85, and amplifies the signal light transmitted through the optical fiber 83a. The pump laser oscillator 84 generates pump light (excitation light) having a wavelength λ2 having a constant light intensity and outputs the pump light to the optical fiber 83d. The optical coupler 83b combines the pump light transmitted through the optical fiber 83d and the signal light having the wavelength λ1 transmitted through the optical fiber 83a, and outputs the combined light to one end of the optical fiber amplifier 85. The optical fiber amplifier 85 adds a substance (erbium) that causes an amplification action or a substance (germanium, aluminum, etc.) that adjusts the refractive index to the core part of the optical fiber, and is amplified with pump light that gives energy to the core part. The signal light is amplified by injecting and propagating the signal light. The other end of the optical fiber amplifier 85 is connected to the optical fiber 13a, and the amplified signal light is input to one end of the optical fiber 13a.
[0042]
The signal light propagated through the optical fiber 13 a is input to the optical circulator 17. The optical circulator 17 outputs the output from the laser transmitter 10 to the external space from the laser opening 2 and also receives the received laser light (received light) reflected by the external reflection point and returned through the laser opening 2. Input to the optical fiber 13c.
[0043]
The laser beam input from the optical fiber 13c to the laser receiver 11 is converted into an electrical signal and then output to the signal processing unit 4 as a reception data signal Si. The laser receiver 11 includes an optical mixer 94, an optical fiber 13d, and an optical receiver 111. The optical receiver 111 includes a lens 11a, a light receiving element 11b, a preamplifier 11c, and a receiving circuit 11d. Received light transmitted through the optical fiber 13c is input to the optical mixer 94 and modulated by the modulation signal So. The optical mixer 94 is a device that modulates light intensity with an external signal, and is configured using a device similar to the modulator 81 and a driver circuit 82. In other words, the optical mixer 94 transmits the optical fiber 13c by adjusting the amplitude and shaping the amplitude of the modulated signal So using the driver circuit 82, and inputting the output signal of the driver circuit 82 to the modulator 81 to modulate the received light. The intensity modulation component of the laser beam and the modulation component of the modulation signal are caused to interfere with each other to generate a beat in the intensity modulation component of the laser beam and output it to the optical fiber 13d. The intensity modulation component of the beat has a frequency lower than that of the intensity modulation component of the laser beam transmitted through the optical fiber 13c. Therefore, the light intensity is square-detected (or envelope detection), and the intensity modulation component is converted into a current signal. The light-receiving element 11b that converts to a high-speed response becomes unnecessary. The output light of the optical fiber 13d is collected by the lens 11a and input to the light receiving element 11b. The optical signal input to the light receiving element 11b is converted into a current signal by the light receiving element 11b and converted into a voltage signal by the preamplifier 11c. The output voltage of the preamplifier 11c is input to the reception circuit 11d, and after waveform shaping is performed, the reception data signal Si is output.
[0044]
FIG. 8A is a diagram illustrating an example of the waveform of the laser light modulated by the modulation signal So and emitted to the external space. The modulated laser light is subjected to so-called FM-CW modulation in which the intensity of the output light is intensity-modulated and the frequency continuously changes.
FIG. 8B is a diagram illustrating an example of the waveform of the modulation signal So and the received light input to the optical mixer 94. In the figure, the horizontal axis indicates time, the vertical axis indicates frequency, and the modulation signal So is frequency-modulated so that the frequency F1 has a peak.
Here, when the modulation signal So peaks at time T1, the frequency of the received light peaks at time T2. From this time difference (T2−T1), the distance to the reflection point when the transmitted light of the laser aperture 15 is reflected in the external environment can be obtained. Further, when the reflection point is moving, the Doppler effect is generated by the speed Vr, so that the peak frequency F2 of the received light is different from F1. In the example of FIG. 8, since it is assumed that the reflection point is approaching, F1 <F2. At this time, the velocity Vr is obtained by the following equation (1).
[0045]
[Expression 1]

[0046]
FIG. 8C is a diagram illustrating a waveform of beat light output from the optical mixer 94. The optical mixer 94 outputs beat light shown in FIG. 8C as a differential signal from the modulated signal So and the received light shown in FIG. 8B. Here, since T1 and T2 respectively match in FIGS. 8B and 8C, the lower transition point when the trapezoidal waveform indicated by the beat light in FIG. 8C transitions from the bottom to the top. If P1 (the vertex below the trapezoidal waveform) and the upper transition point P2 (the vertex above the trapezoidal waveform) are measured by the light receiving element 11b, the distance is measured by obtaining the time between the points P1 and P2. Can do. In particular,
Distance D = (T2−T1) × C / 2 (Formula (2))
Can be obtained.
Further, the speed can be measured using the frequencies of the points P1 and P2. Specifically, the speed Vr can be obtained by the following equation (3). The laser receiver 11 converts an optical signal into an electrical signal and outputs a received data signal Si, and the signal processing unit 4 measures the distance and speed based on the received data signal Si (for details, see FIG. Will be described later).
[0047]
[Expression 2]

[0048]
FIG. 9 is a diagram showing the configuration of the signal processing unit 4. In the figure, the signal processing unit 4 includes an image processor 101, a distance measuring device 102, a switch selector 103, a controller 104, and an attitude / direction reference device 304.
The image processor 101 receives the image signal output from the camera 16 through the electric signal cable 18a. The image processor 101 extracts an image (target) indicating the target from the subject based on the image signal from the camera 16. Further, the image processor 101 predicts the future position of the extracted target. The controller 104 selects a laser opening 15 and a laser directing direction so that the target future position falls within the laser light irradiation region from among the plurality of laser openings 15. In addition, the switch information corresponding to the laser directivity direction is transmitted to the switch selector 103. The switch selector 103 transmits a switching signal to the optical switch 12 and the optical switch 61 via the electric signal cable 20a based on the switch information corresponding to the laser opening 15 and the directivity direction. Thus, the optical switch 12 and the optical switch 61 connect the optical path between the laser opening 15 and the ferrule 63 and the laser transmitter 10. The distance measuring device 102 sends a laser emission command signal to the power supply unit 5 through the electric signal cable 20c, and emits the laser beam from the laser transmitter 10 at a timing at which the target can be irradiated with the laser beam. The distance measuring device 102 operates as a signal generator that transmits the modulation signal So to the driver circuit 82 of the laser transmitter 10 via the electric signal cable 20b and generates the modulation voltage signal Vm and the bias signal Vb. The distance measuring device 102 modulates the received light that has sent the modulation signal So to the laser receiver 11 via the electrical signal cable 20d, and also receives the received data signal input to the laser receiver 11 via the reception cable 20d. Based on Si, the distance D to the reflection point of the laser beam output to the external space and the velocity Vr of the reflection point are obtained from the above equations (2) and (3).
[0049]
Next, a detailed configuration of the image processor 101 will be described with reference to FIG.
The image processor 101 includes an image detector 111, a target extractor 112, a prediction calculator 113, and a target database 115. The image detector 111 inputs the altitude, speed, acceleration, attitude angle, attitude angular velocity, attitude angular acceleration of the aircraft as the aircraft information 19c from the attitude azimuth reference unit 304, and performs coordinate conversion on the image captured by the camera 16. At the same time, an image composed of a group of pixels is extracted from the image by a known image processing technique such as a spatial filter, binarization processing, or correlation processing. The posture / azimuth reference device 304 includes an altimeter, a gyro, or the like.
[0050]
The target extractor 112 extracts the illuminance (illuminance information) and the contour shape (shape information) of the extracted image, measures the movement of the center of gravity of the image, and extracts the trajectory pattern (trajectory pattern information) of the image. To do. These extracted illuminance information, shape information, and trajectory pattern information are referred to as image information. The target extractor 112 determines that the trajectory pattern is linear movement when the length of linear movement of the image is equal to or greater than a certain length. Further, the target extractor 112 determines whether the image is horizontal, ascending, descending, random, or fixed based on the direction of image movement in the trajectory pattern information. Further, the target extractor 112 indicates that the trajectory pattern information exists at a higher altitude than the camera 16 if the height at which the linear movement is performed is higher than a predetermined pixel in the image from the horizontal plane. judge. The target database 115 stores in advance target information indicating the characteristics of the target to be detected. In the target information, illuminance information, shape information, trajectory pattern information, discrimination information, and the like are stored for each target to be detected, corresponding to the image information. The discrimination information is information indicating a distinction between what should be selected as a target in advance and what should not be selected as a non-target.
[0051]
The table of FIG. 11 is a diagram showing an example of the data structure of the target database 115, and shows an example of target information for each target corresponding to the detection target. As shown in the table, the target database 115 virtually constitutes a two-dimensional matrix in the memory area, the name of the target to be detected is stored in the row (COL) of the matrix, and the column (ROW) is detected in each row. The target information corresponding to the target target is shown. The target extractor 112 refers to the target information stored in the target database 115 and compares the target information having the feature closest to the image information by comparing with the previously extracted image information. judge.
[0052]
For example, as shown in FIG. 12, an image corresponding to a cloud 203 other than the target is present in the image detected by the image detector 111 at the same time as a flying object such as an aircraft 201 or a rocket 202 as a target. Further, a case where the sea surface reflection 204 is included is assumed.
[0053]
According to the figure, since the rocket 202 and the aircraft 201 generate jet gas from the rear, the illuminance from the rocket 202 and the aircraft 201 is relatively high when the camera 16 captures it as an infrared image. Can be identified. In the rocket and the aircraft, an image with high illuminance (relatively high illuminance) moves in the horizontal direction or upward along a linear trajectory pattern in the screen of the camera 16. On the other hand, the sea surface reflection has high illuminance from the sea surface, but its position takes a different locus from that of the rocket or aircraft in the target database 115, and the shape of the image is large, so that it can be distinguished from the image of the rocket or aircraft. Based on such feature points, a target image can be selected from a plurality of images.
[0054]
For example, when it is desired to select the aircraft 201 or the rocket 202 as a target, the illuminance information indicates medium illuminance (relatively medium illuminance), the shape information is small, and the trajectory pattern information is based on the characteristics of the image in the image. The one that moves horizontally in a straight line is determined that the target extractor 112 is the aircraft 201 and is selected as the first target. In addition, when the illuminance information indicates high illuminance, the shape information is small, and the trajectory pattern information rises linearly from below the horizontal plane, it is determined that the target extractor 112 is the rocket 202 and is selected as the second target. To do.
[0055]
Next, for the target selected as the target in the image, the target extractor 112 detects the position of the center of gravity in the screen as the target position. In the example of FIG. 12, the gravity center positions G1 and G2 are determined to be the positions where the first and second targets are present, respectively. The first and second targets appear in the screen at the positions OG1 and OG2, determine the moving direction of the image from the locus of the image, and further determine the speed of position change in the image. For example, the first target speed is determined as V1, and the second target speed is determined as V2. Based on the target extraction result, the target extractor 112 displays the information on the target position in the screen and the traveling direction of the target on the display 21 via the electric signal cable 19b. Send it out. In addition, the target extractor 112 transmits, to the prediction calculator 113, the target location, information on the target traveling direction, and the locus of the target center of gravity as target state information.
[0056]
Based on the information sent from the target extractor 112, the display 21 shows a symbol such as a circle indicating the position of the target in the screen of the display 21 and in which direction the target is progressing. Display symbols such as arrows. In addition, the display 21 transmits a surrounding image including the target processed by the image detector 111 via the electric signal cable 19a, and displays the image. If there are multiple targets, numbers may be displayed in a circle symbol. FIG. 13 is a diagram showing an example of symbol display on the display 21. In the figure, (1) and (2) indicate targets.
[0057]
In addition, when the illuminance ratio of a plurality of target wavelengths is known in advance as target information, the probability that the signal processing unit 4 extracts an erroneous object as a target by using a multi-wavelength camera as the camera 16 is obtained. Can be reduced. For example, when the camera 16 has sensitivity in two types of wavelength bands, λ3 and λ4, the signal intensity ratio is added to the target database 115 by adding a signal intensity ratio term in the wavelength band of λ3 and λ4 for each target. However, targets that differ from rockets and aircraft can be undetected as targets.
[0058]
In addition, the prediction calculator 113 predicts the future position of the target based on the target state information output from the target extractor 112. As the target state information, the current position of the target, the target speed, and the past position information are transmitted as the target locus. For example, in the case of the example in FIG. 12, with respect to the target 202, since the trajectory connecting the past position OG2 and the current position G2 is a straight line based on the current position G2 and the speed V2, the future position after T seconds is set to MG2. (MG2 position coordinates = G2 position coordinates + velocity vector V2 × T). In calculation, acceleration may be used. When the locus is a curve, the position on the extension of the curve may be predicted based on the current position and the current speed. The prediction computing unit 113 transmits the predicted future position to the controller 104.
[0059]
The controller 104 includes a target future position within the laser light irradiation region from among the plurality of laser openings 15 within the entire circumferential opening surface formed by adding the coverage areas of the plurality of laser openings 15. The laser aperture 15 is selected. At this time, output port designation information for selecting the input / output port 52 of the optical switch 12 is sent to the switch selector 103 so that the selected laser aperture 15 and the optical fiber 13b are connected. The switch selector 103 sends a switching signal for switching the connection to the optical switch 12 based on the designation information of the selected output port, and the optical switch 12 performs a connection switching operation. Further, in the selected laser aperture 15, the directivity direction of the laser output unit 60 is set so that the optical axis (directive direction) of the laser light deflected by the laser output unit 60 faces the direction in which the target future position exists. Set. In this setting, the laser output unit 60 in the laser aperture 15 is selected corresponding to the camera 16 having the target future position in the screen. At this time, the directivity direction of the laser output unit 60 corresponding to the angle of view of the camera 16 is defined in advance.
[0060]
For example, it is preferable to set the deflection angle θm of the laser output unit 60 as it is within the angle of view of the camera 16. In this case, the deflection angle θm of the laser output unit 60 is set to the angle of view θg in the target future position direction, and the set deflection angle θm is transmitted to the controller 104. Based on the deflection angle θm of the laser output unit 60, the controller 104 selects the corresponding optical switch so that the ferrule 63 including the deflection angle θm within a predetermined angle range (15 ° in the example of FIG. 5) is selected. 61 output ports are set. Further, the rotation angles of the wedge prisms 66a and 66b are set so that the angle difference becomes 0 based on the angle difference between the angle of the ferrule 63 with respect to the reference axis B0 and the desired deflection angle θm. The controller 104 sends designation information of the selected output port to the switch selector 103. The switch selector 103 sends a switching signal for switching the connection to the optical switch 61 based on the output port designation information, and the optical switch 61 performs a connection switching operation. Further, the controller 104 sends rotation angle information to an actuator that rotationally drives the wedge prisms 66a and 66b. Based on this, the wedge prisms 66a and 66b adjust the angle so that the rotation angle becomes an angle set by the rotation angle information.
[0061]
Further, the controller 104 monitors whether or not the optical switch 12 and the optical switch 61 are surely switched to the desired connection based on the designation information of the output port, and as a result of monitoring, the controller 104 determines the desired connection. If not switched to, an alarm signal 19 is issued to the display 21. Based on the alarm signal 19, the display 21 displays, for example, “malfunction” as warning information indicating malfunction.
[0062]
The distance measuring device 102 detects the laser beam reflected by the target from the time when the laser aperture 15 emits the laser beam based on the time between the transition points of the reception data signal Si transmitted from the laser receiver 11. The distance D between the target and the dispersion aperture 2 is calculated by the above equation (2) by measuring the difference up to the time of incidence on the portion 15 and multiplying that value by half the speed of light. Can do.
[0063]
Further, based on the above equation (3), the dispersion aperture is determined from the frequency at each transition point of the reception data signal Si transmitted from the laser receiver 11 and the maximum frequency of the modulation signal So transmitted to the laser transmitter 10. The target speed for part 2 can be determined.
[0064]
FIG. 14 is a diagram illustrating a configuration example of the optical switch 12 and the optical switch 61. 14A and 14B, reference numerals 120 and 600 denote micromirrors, which change the reflection direction by being moved up and down by a microactuator such as a piezoelectric element (not shown) provided below. For example, in FIG. 14A showing the configuration example of the optical switch 12, when the input / output port 51 is connected to the input / output port 52f, the mirror 120a and the mirror 120b are lifted to output from the input / output port 51. The laser beam is output from the input / output port 52f. In FIG. 14B showing the configuration example of the optical switch 61, when the input / output port 61a is connected to the input / output port 61h, it is output from the input / output port 61a by lifting the mirror 600a and the mirror 600b. The laser beam is output from the input / output port 61h. In the normal state, all the mirrors are lowered. The operations of the mirror 120 and the mirror 600 are controlled up and down by the switch selector 103.
[0065]
In the laser apparatus 1 configured as described above, laser light can be emitted in a desired direction in a short time. For example, when a conventional gimbal is used to control the transmission direction of laser light, it takes time to mechanically drive the gimbal, so a time in seconds is required to direct the laser light in the desired direction. Cost. On the other hand, in the laser device according to the first embodiment in which the laser apertures 15 are dispersedly arranged, the laser beam can be accurately directed in a desired direction in about 1 / 100th of the time. Further, the mechanical drive part for directing the laser beam is limited to the wedge prisms 63a and 63b and the optical switch for minutely displacing the mirror surface, and can be configured in a small size. Since the number is reduced, the maintenance of the apparatus becomes easy. In addition, it is possible to reduce the load of signal processing related to drive control.
[0066]
If the positional relationship between the target and the dispersion aperture 2 does not change, the target can be irradiated with laser light and the laser light from the target can be received without the tracking function of the camera 16 and the signal processing unit 4. it can.
[0067]
According to this embodiment, the connection between the laser transmitter 10, the plurality of optical fibers 14 that transmit laser light between one end and the other end, and the connection between the laser transmitter 10 and one end of the plurality of optical fibers 14 is switched. The optical switch 12 includes a plurality of laser apertures 15 that are coupled to the other ends of the plurality of optical fibers 14 and dispersedly arranged so as to output the laser light transmitted through the optical fibers 14 to the external space. Accordingly, it is possible to provide a laser device that can change the laser emission direction or the incident direction in a short time.
[0068]
Further, by dispersively arranging the dispersion openings 2 on the aircraft, laser light can be emitted in a desired direction within a 360 ° field of view around the aircraft, and the installation height of the dispersion openings 2 can be set to It can be installed so that the height is substantially the same as the body surface, or the protruding height from the body surface is 10 mm or less. Thereby, the air resistance accompanying the installation of the dispersion opening 2 is reduced, and the influence on the aerodynamic characteristics of the aircraft can be suppressed.
[0069]
For example, in a conventional laser device as disclosed in Patent Document 1, the height of a gimbal having a hemispherical shape reaches 100 mm to 500 mm, and the protruding height from the fuselage surface of the aircraft is 100 mm or more. As a result, an aircraft capable of flying at a maximum speed of Mach number 2 is limited in flight speed by the influence of air resistance accompanying the protruding height of the gimbal, and must fly at Mach number 1, for example. Disappear. On the other hand, in this embodiment, since the gimbal is not used, the protrusion height from the aircraft fuselage surface can be 10 mm or less, the air resistance can be extremely reduced, and the laser device is mounted. However, it is possible to fly at a speed close to Mach number 2, which is almost the maximum speed.
[0070]
In addition, since the protrusion height can be lowered in this way, the change in the laser cross-sectional area due to the installation of the laser device on the aircraft fuselage surface can be reduced, and the stealth property associated with the mounting of the laser device. Can be improved.
[0071]
Further, since a signal processor for servo system control for driving and controlling the attitude angle of the gimbal becomes unnecessary, the signal processor can be made smaller and simpler. Further, since the gimbal itself is not used, the number of driving parts is reduced, and maintenance is easier.
[0072]
In addition, since the opening for emitting laser light has a simpler structure than the gimbal, the opening can be reduced in size.
[0073]
In addition, since it is configured to be able to oscillate using a fiber laser oscillator (80d, 500), the optical fiber is routed in a narrow space as if a cable is placed in a narrow space, or rounded as necessary. And the restrictions on the arrangement position and the arrangement space are alleviated. For this reason, it is possible to disperse the laser openings.
[0074]
The optical transmission path that connects between the fiber laser oscillator and the laser aperture can be configured using an optical fiber, so it is necessary to configure the optical transmission path by accurately arranging reflective optical components such as mirrors and prisms. In addition, there is no need to use a heavy and strong structure for supporting the reflective optical component so that the optical axis of the reflective optical component is not displaced.
[0075]
In addition, since the optical transmission path is configured using an optical fiber, it is not necessary to increase the cleanliness of the air in the space between the reflective optical components when the optical transmission path is configured by appropriately arranging the reflective optical components.
[0076]
Also, an optical modulator 81 that performs FM-CW modulation on continuous light from a laser oscillator, an optical amplifier 83 that amplifies output light from the optical modulator 81, reflected light from a target, and a signal generator (rangefinder 102) Since an FM-CW modulation type laser radar can be configured with an optical mixer that modulates the received light based on the output signal, coherent integration by FFT (Fast Fourier Transform) is possible, and low power Remote distance measurement is possible with laser light. In particular, since the laser power is small, the power resistance performance of the optical system and the cleanness of the air in the space on the laser optical path can be designed low. Further, compared with a laser radar that is generally widely used using a pulse laser, a high-speed response of the optical receiver is not required, and reflected light can be received with high impedance. Furthermore, since Doppler can be detected simultaneously, the target velocity can be detected by irradiating a modulated continuous light laser and integrating the time.
[0077]
Further, by providing a plurality of cameras 16 having the optical axis direction of the lens 65 in the field of view around each lens 65, the target in the image of the camera 16 can be irradiated with laser light. Furthermore, it is possible to confirm the situation in the direction in which the laser beam is irradiated and received by an image.
[0078]
Furthermore, since a target having the same characteristics as the desired target can be detected from the video and the target can be irradiated with a laser beam, for example, a target (for example, a missile) that becomes a threat to fly toward the aircraft can be detected. It can be found by the camera 16 and irradiated with a laser beam to obstruct the target flight.
[0079]
Embodiment 2. FIG.
In the laser apparatus of this embodiment, a fiber laser is used to oscillate using a fiber laser, and separately from the first optical fiber system that connects the laser transmitter 10 and the wavelength converter 52, the fiber laser and the wavelength converter The other 2nd optical fiber type | system | group which connects is comprised. The wavelength converter 52 according to this embodiment uses the two wavelengths of the output wavelength λ1 of the fiber laser oscillator 500 and the output wavelength λ2 of the laser transmitter 10 described in the first embodiment to constitute the wavelength constituting the OPA. The converter 52 converts the wavelength of the laser light.
[0080]
FIG. 15 is a diagram illustrating a configuration of a laser apparatus according to the second embodiment. In the figure, the input end of the fiber laser oscillator 500 is connected to a pump laser oscillator 501. The pump laser oscillator 501 is connected to the input end of the fiber laser oscillator 500. The pump laser oscillator 501 generates pump light (excitation light) having a wavelength λ01 (= 0.81 μm) having a constant light intensity, and outputs it to one end of the fiber laser oscillator 500. The output end of the fiber laser oscillator 500 is connected to one end of the optical fiber 300, the other end of the optical fiber 300 is connected to the input port 201a of the optical switch 200, and the fiber laser oscillator 500 has a wavelength λ2 (= 1.06 μm). The laser beam is output.
[0081]
The output end of the laser transmitter 10 is connected to one end of the optical fiber 13 a, and the other end of the optical fiber 13 a is connected to the input / output port of the optical circulator 17. As described above, the laser transmitter 10 has the fiber laser oscillator 80d and outputs laser light having a wavelength λ2 (= 1.55 μm). The laser receiver 11 is connected to the output port of the optical circulator 17 through an optical fiber 13c. One end of the optical fiber 13b is connected to the input / output port of the optical circulator 17, and the other end of the optical fiber 13b is connected to the input / output port 201b of the optical switch 200. Input / output ports 202 (202a to 202f) and 203 (203a to 203f) of the optical switch 200 are connected to one ends of optical fibers 400 (400a to 400f) and 14 (14a to 14f), respectively. The other ends of the optical fibers 400 (400a to 400f) and 14 (14a to 14f) are connected to the wavelength converter 52 (52a to 52f). The optical fiber 67 provided in the wavelength converter 52 (52a to 52f) is connected to the laser output unit 60 (60a to 60f).
[0082]
The laser apparatus according to this embodiment is configured as described above and operates as follows.
The fiber laser oscillator 500 shown in FIG. 15 and the fiber laser oscillator 80d shown in FIG. 7 are connected in series to a rare earth-doped fiber laser containing an active material that activates the stimulated emission effect, or a stimulated emission optical fiber. A Raman fiber laser containing an active substance that activates the nonlinear effect is used. The fiber laser has a pair of reflecting means at both ends. As the reflecting means, a mirror or a fiber grating that reflects oscillating light is used, and a Fabry-Perot resonator is configured with a fiber laser interposed therebetween.
[0083]
The rare earth-doped fiber laser is configured by doping a rare earth element such as Nd, Ho, Er, Tm, and Yb into the core that forms the center of an optical fiber such as quartz, fluoride, or phosphate. In this example, since the excitation light of the fiber laser oscillator 500 is 0.81 μm, Nd is used as the rare earth element. Further, since the excitation light of the fiber laser oscillator 80d is 0.98 μm, Er is used as the rare earth element. These excitation lights are input to the rare earth doped fiber through the reflecting means. When the excitation light passes through the core of the rare earth-doped fiber, the outermost electrons of the rare earth element doped in the core are excited to have an inverted distribution, and spontaneous emission light is emitted. The spontaneous emission light is amplified while reciprocating between the pair of reflecting means by the stimulated emission effect, and finally enters an oscillation state. Part of the oscillation light (laser light) is transmitted through the reflecting means and output as laser light having a desired wavelength.
[0084]
In the case of using a Raman fiber laser, a quartz optical fiber and a pair of reflecting means arranged with the optical fiber interposed therebetween are provided. In this Raman fiber laser, a Fabry-Perot resonator is configured by sandwiching an optical fiber by a pair of reflecting means such as a fiber grating, as in the case of a rare earth doped fiber. In the Raman fiber laser, high-power excitation light is input from one end of the fiber laser through the reflecting means. In a Raman fiber laser, when high-power pumping light passes through an optical fiber, part of the pumping light shifts to the longer wavelength side due to the interaction between light and optical photons (lattice vibration), and natural Raman scattering occurs. Light is obtained. Then, by stimulated Raman scattering (nonlinear effect), natural Raman scattered light is amplified while reciprocating between the pair of reflecting means, and finally enters an oscillation state. A part of the oscillation state light (laser light) passes through the reflecting means and is output as laser light having a desired wavelength.
[0085]
The optical switch 200 has an input port 201 a connected to one end of the fiber laser oscillator 500. The input port 201b is connected to the other end of the optical fiber 13b. The input / output ports 202 (202a to 202f) and 203 (203a to 203f) of the optical switch 200 are connected to one end of the wavelength converter 52 (52a to 52f). The other end of the wavelength converter 52 (52a to 52f) is connected to the laser output unit 60 (60a to 60f). The optical switch 200 connects the input / output port 201a to the input / output port 202 (202a to 202f). The optical switch 200 connects the input / output port 201b to the input / output port 203 (203a to 203f).
[0086]
Thus, the optical fibers 80c, 83a, 13a, 13b, and the optical fiber 203 constitute a first optical fiber system. Further, the fiber laser oscillator 500, the optical fiber 300, and the optical fiber 202 constitute a second optical fiber system. The optical fiber in the first optical fiber system is a single mode suitable for transmitting a 1.5 μm wavelength optical signal so as to reduce loss when transmitting the first laser beam having a wavelength of 1.55 μm. Fiber is used. In addition, the optical fiber in the second optical fiber system is a single mode suitable for transmitting an optical signal in the wavelength band of 1 μm so that the loss when transmitting the second laser light with a wavelength of 1.06 μm is reduced. Fiber is used. These single mode fibers are relatively available.
[0087]
The first laser beam transmitted through the first optical fiber system is input to the lens 71 as in the wavelength converter 52 (52a to 52f) shown in FIG. At the same time, the second laser light transmitted through the second optical fiber system is input to the lens 71 of the wavelength converter 52. In the wavelength converter 52, the first and second laser beams collected by the lens 71 are input to the nonlinear optical unit 70, and wavelength-converted with the first laser beam amplified by the parametric amplification action. The third laser light is output to the optical fiber 67. For example, laser light having a wavelength of 3 μm is output as the third laser light.
[0088]
Here, the third laser beam having a wavelength of 3 μm can be used, for example, to disturb the operation of the electromagnetic wave reception sensor of another laser device. For example, it is assumed that the target is a flying object and a seeker for detecting infrared rays is provided at the tip of the flying object. In this case, a laser beam having a high level that matches the detection wavelength (for example, in the 3 μm band) of the seeker and that saturates the light receiving sensitivity of the detector of the seeker is emitted from the laser aperture 15. At this time, by using the fiber laser oscillator 500, the output power of the third laser beam can be increased to an appropriate level. As a result, the laser device of this embodiment can be operated as a flying object obstruction device.
[0089]
When the flying body seeker is used as such a disturbing device, it is not assumed that the third laser beam is reflected and returned by the target, and only the first laser beam in the 1.5 μm band is the target. It is sufficient that the reflected light reflected from the light can be received.
[0090]
As the optical fiber 62 that constitutes the laser output unit 60, an optical fiber that transmits laser light of 1.5 μm band and 3 μm band with high efficiency is used. In general, an optical fiber that transmits both the 1.5 μm band and the 3 μm band has a lower transmittance than the 1.5 μm band optical fiber used for communication, but the length of the optical fiber 62 is short, which is problematic. Must not. As a result, in the path from the first optical fiber system to the opening surface (lens 65) of the laser output unit 60, the first laser light in the 1.5 μm band and the third laser light in the 3 μm band are laser output. It is possible to transmit to the unit 60 without loss. Further, since the second laser beam in the 1 μm band is transmitted from the fiber laser oscillator 500 using the second optical fiber system, the second laser beam in the 1 μm band is transmitted between the laser converter 60 and the wavelength converter 52. Transmission can be performed without loss using laser light. In this case, the laser light having a wavelength of 3 μm band converted by the wavelength converter 52 passes through the optical fiber 67, but there may be some transmission loss.
[0091]
With such a configuration, laser light is transmitted using an optical fiber matched to the transmission wavelength band, and a wavelength converter is disposed immediately before the opening surface of the laser output unit to convert the wavelength of the laser light. It is possible to transmit laser light with a small amount of light and convert the wavelength.
[0092]
The laser device according to this embodiment includes a plurality of types of wavelength converters 52 that generate laser beams having different wavelengths from input laser beams and output the generated laser beams to the respective laser openings 15. Since the target can be irradiated with laser light having a wavelength of, the laser light irradiated to the target can be used properly according to the type of sensor of the target irradiated with the laser light.
[0093]
Also, a pair of fiber laser oscillators 80d that generate laser beams of first and second wavelengths having different wavelengths and a fiber laser oscillator 500, which transmit laser beams corresponding to the first and second wavelengths, respectively. By providing a plurality of optical fiber pairs (400, 14), each of the optical fiber pairs (400, 14) is connected to each other and has a different wavelength based on the input laser light of the first and second wavelengths. By providing a plurality of wavelength converters 52 that generate laser light of the third wavelength and output the generated laser light of the third wavelength to the laser aperture 15, the optical switch 12 includes a fiber laser oscillator 80d, And 500 and a plurality of optical fiber pairs (400, 14) are switched so that two targets can be irradiated with laser light at the same time. Also, by providing a redundant system, even if one of the first and second laser oscillators fails, laser irradiation can be continued with the other laser oscillator.
[0094]
Embodiment 3 FIG.
In the first embodiment, the laser output unit 60 (60a to 60f) is configured using the wedge prisms 66a and 66b and the ferrules 63 arranged discretely so as to face the center of curvature of the sphere. However, as the laser output unit, other mechanisms may be used as long as the laser directivity angle is adjusted so as to envelope a solid angle of 90 ° × 90 °.
[0095]
In this embodiment, for example, the lens 65 is disposed on a small gimbal that can be driven only in an angle range of 90 ° × 90 °, and an optical system that guides laser light to the lens 65 is configured. As a result, it is possible to realize an optical system that deflects the direction of the laser light with a relatively simple configuration. As such a gimbal, a small gimbal may be configured by limiting a movable angle of a large gimbal as described in Patent Document 1.
[0096]
Embodiment 4 FIG.
In the fourth embodiment, the modulation signal So for optical communication may be output from the laser transmitter 10. For example, an NRZ (Non Return to Zero) signal used in optical fiber communication may be output from the laser transmitter 10. The laser transmitter 10 emits laser light from the laser aperture 15 and receives the laser light with another laser device arranged in the laser light irradiation direction. Further, the laser receiver 11 causes the laser apparatus to function as a receiver for optical communication when the wavelength band of the laser beam to be transmitted matches the reception wavelength band of the laser receiver 11 of the laser apparatus.
[0097]
Embodiment 5 FIG.
In the first embodiment, an example in which a laser device is mounted on an aircraft has been described. However, the laser device as described in Embodiment 1 may be mounted on another moving body. For example, it may be configured by a vehicle moving on land, a ship moving on water, an aircraft flying in the air, or an artificial satellite flying in outer space. In this case, the laser device can be easily moved, and the function of the laser device can be added to the moving body. In addition, the resolution of a camera with a field of view in the moving direction of the moving object may be higher than the resolution of a camera with a field of view in other directions. In this case, obstacles and targets ahead of the moving direction are found far away. It can be done easily.
[0098]
【The invention's effect】
According to the present invention, as described above, it is possible to provide a laser apparatus capable of changing the laser emission direction or the incident direction in a short time.
[Brief description of the drawings]
FIG. 1 is a diagram showing a state in which a laser apparatus according to Embodiment 1 of the present invention is mounted on an aircraft.
FIG. 2 is a diagram showing an arrangement of opening surfaces when the laser device according to the first embodiment of the present invention is mounted on an aircraft.
FIG. 3 is a diagram illustrating the configuration of a laser device according to Embodiment 1 of the present invention.
FIG. 4 is a perspective view showing an appearance of a dispersion opening of the laser apparatus according to Embodiment 1 of the present invention.
FIG. 5 is a diagram showing a configuration of a laser aperture of the laser apparatus according to Embodiment 1 of the present invention.
FIG. 6 is a diagram showing a configuration of a wavelength converter of the laser device according to the first embodiment of the present invention.
FIG. 7 is a diagram showing a configuration of a laser transceiver of the laser device according to the first embodiment of the present invention.
FIG. 8 is a diagram for explaining the waveform of beat light output from the optical mixer of the laser apparatus according to Embodiment 1 of the present invention;
FIG. 9 is a diagram showing a configuration of a signal processing unit of the laser apparatus according to Embodiment 1 of the present invention.
FIG. 10 is a diagram showing a configuration of an image processor of the laser apparatus according to Embodiment 1 of the present invention.
FIG. 11 is a diagram showing a configuration of a target information database of the laser apparatus according to Embodiment 1 of the present invention.
FIG. 12 is a diagram showing an example of a target image according to the first embodiment of the present invention.
FIG. 13 is a diagram showing symbol display on the display according to the first embodiment of the present invention.
FIG. 14 is a diagram showing an example of an optical switch according to Embodiment 1 of the present invention.
FIG. 15 is a diagram showing a configuration of an optical switch and a wavelength converter according to Embodiment 2 of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Laser apparatus, 2 Dispersion opening part, 3 Laser transmitter / receiver, 4 Signal processing part, 5 Power supply part, 10 Laser transmitter, 11 Laser receiver, 12 Optical switch, 13a, 13b Optical fiber, 14a, 14b Optical fiber, 15 Laser aperture, 16 Camera, 52 Wavelength converter, 53 Optical window, 54 Optical window, 55 Top cover, 60 Laser output, 61 Optical switch, 62 Optical fiber, 63 Ferrule (optical fiber terminal), 65 Lens, 66a, 66b Wedge prism, 80 laser oscillator, 81 optical modulator, 82 driver circuit, 83 optical amplifier, 92 optical mixer, 101 image processor, 103 switch selector, 104 controller, 200 optical switch, 500 fiber laser.

Claims (15)

A laser light source for outputting laser light;
A plurality of optical fibers for transmitting laser light between one end and the other end;
An optical switch that switches connection between the laser light source and one end of the plurality of optical fibers;
A plurality of lenses that are respectively coupled to the other end sides of the plurality of optical fibers, and that output laser light transmitted through the optical fibers to an external space;
The laser apparatus according to claim 1, wherein optical axes of the plurality of lenses are arranged so that their directing directions are different from each other. 2. A wavelength converter connected to each of the optical fibers, generating a laser beam having a different wavelength from the input laser beam, and outputting the generated laser beam to each lens. Laser equipment. The laser light source includes first and second laser oscillators that generate laser beams of first and second wavelengths having different wavelengths,
The plurality of optical fibers include a plurality of pairs of optical fibers that transmit laser light corresponding to the first and second wavelengths,
A third wavelength laser beam generated by generating a third wavelength laser beam having a different wavelength based on the input first and second wavelength laser beams connected to each optical fiber pair. A plurality of wavelength converters for outputting light to the respective lenses;
2. The laser apparatus according to claim 1, wherein the optical switch is configured to switch connection between the first and second laser oscillators and the plurality of optical fiber pairs. The laser device according to claim 2, wherein the wavelength converter is configured by an optical parametric amplifier. The laser light source includes first and second laser oscillators that generate signal light and pump light, respectively.
The plurality of optical fibers include a plurality of pairs of optical fibers that transmit laser light corresponding to the signal light and the pump light, respectively.
A plurality of optical parametric amplifiers connected to each of the optical fiber pairs and amplifying the input signal light with the input pump light;
2. The laser apparatus according to claim 1, wherein the optical switch is configured to switch connection between the first and second laser oscillators and the plurality of optical fiber pairs. 6. The laser device according to claim 1, wherein the laser light source is a fiber laser. The first laser oscillator includes a fiber laser that outputs continuous light, an optical modulator that modulates output light of the laser light source, and an optical amplifier that amplifies output light of the optical modulator,
6. The laser apparatus according to claim 3, wherein the second laser oscillator is configured by a fiber laser. A laser receiver for receiving laser light;
A plurality of optical fibers for transmitting laser light between one end and the other end;
An optical switch that switches connection between the laser receiver and one end of the plurality of optical fibers;
A plurality of lenses coupled to the other ends of the plurality of optical fibers, respectively, and receiving incident light from an external space;
The laser apparatus according to claim 1, wherein optical axes of the plurality of lenses are arranged so that their directing directions are different from each other. A laser oscillator that outputs continuous light;
A signal generator for generating a modulation signal;
An optical modulator that modulates continuous light from a laser oscillator based on an output signal of the signal generator;
An optical amplifier for amplifying output light of the optical modulator;
An optical mixer that modulates the received light based on the reflected light from the target and the output signal of the signal generator;
A plurality of optical fibers for transmitting laser light between one end and the other end;
An optical switch connected to one end of each of the plurality of optical fibers;
An optical circulator that distributes laser light output from the optical amplifier to the optical switch, and distributes reflected light from a target output from the optical switch to the optical mixer;
An optical receiver that outputs a received data signal based on an output signal of the optical mixer;
A plurality of lenses coupled to the other ends of the plurality of optical fibers, respectively, for outputting laser light to the external space or receiving incident light from the external space;
The optical switch switches connection between the optical circulator and one end of the plurality of optical fibers,
The laser apparatus according to claim 1, wherein optical axes of the plurality of lenses are arranged so that their directing directions are different from each other. A wedge prism disposed on the external space side of each lens;
10. The wedge prism according to claim 1, wherein the wedge prism is rotatably supported around an optical axis of each of the lenses, and the laser beam output direction is changed by adjusting a rotation angle thereof. The laser apparatus described. A hemispherical surface facing each of the lenses, and a laser output unit in which a plurality of optical fiber terminals are arranged on the hemispherical surface;
A second optical switch connected to each optical fiber terminal of the laser output unit,
The laser device according to claim 1, wherein the second optical switch switches a connection between the other end of any one of the optical fibers and any one of the optical fiber terminals. The laser apparatus according to claim 1, wherein a plurality of cameras having an optical axis direction of the lens in the field of view are provided around each of the lenses. The laser device according to claim 12, wherein each of the cameras has sensitivity in an infrared region. 13. The laser apparatus according to claim 12, further comprising: a signal processing unit that detects an object having a feature in illuminance, shape, and motion trajectory from the image captured by each of the cameras as a target. Detection means for detecting, as a target, an object having a characteristic in illuminance, shape, motion locus, and luminance ratio of a plurality of wavelengths from the images captured by the respective cameras,
Predicting means for predicting a future position based on the target motion trajectory;
14. A signal processing unit comprising: the optical fiber corresponding to the lens facing the target direction; and a selection unit that switches the optical switch so that the laser light source is connected. The laser apparatus described.

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