JP3607773B2

JP3607773B2 - Ophthalmic imaging equipment

Info

Publication number: JP3607773B2
Application number: JP08724196A
Authority: JP
Inventors: 達也笠原
Original assignee: 株式会社コーナン・メディカル
Priority date: 1996-03-14
Filing date: 1996-03-14
Publication date: 2005-01-05
Anticipated expiration: 2016-03-14
Also published as: JPH09248278A

Description

【０００１】
【発明の属する技術分野】
この発明は、被検者の眼球の角膜内皮細胞や水晶体など被検部細胞を撮影時、前眼部像における撮影部位を正確に知ることのできる眼科撮影装置に関する。
【０００２】
【従来の技術】
コンタクトレンズの影響を見るためや、白内障手術の術前術後の診療に角膜内皮細胞の状態を観察する必要があり、従来から、被検者の眼球の角膜内皮細胞の拡大観察乃至拡大写真撮影のため、被検者の眼球面に対し顕微鏡の対物レンズを非接触型又は接触型として、スリット照明光を眼軸に対し斜方向から被観察部に向け照射し、角膜表面からの反射光と内皮細胞の像光線とを分離して被検部の角膜内皮細胞をテレビカメラ等により撮影するようにした装置が用いられている。
【０００３】
上記装置で観察乃至撮影を行う場合、角膜の拡大観察撮影部位は中央部のみでなく診療内容によっていろんな部位が求められるが拡大観察撮影像のみではどの部位が解らないため之を解決するべく、本出願人は先に特願平５−１９８９５１号において、被検者の角膜内皮細胞を高倍率で観察又は撮影する場合、被検部の内皮細胞のピント合わせを容易に行わせることができ、且つ、観察乃至撮影部位がどの位置か判る角膜内皮撮影装置の提案を行った。この場合、撮影系（撮影装置）を撮影系に備えた前眼部観察光学系の光軸に対しＸＹ方向に移動させ、撮影系から被検眼に投影した位置検出指標の角膜反射光が前眼部観察光学系を介した結像面における前眼部像の所定位置にあるとき前眼部像を記録し、撮影系を被検眼方向に移動させて合焦検知用受光素子で角膜内皮合焦が検知されたときの合焦信号で角膜内皮細胞拡大像を記録し同時に表示させるようにしている。
【０００４】
本出願人は更に、特願平７−３０６５５３号に於て非接触で水晶体上面や後面等被検眼の眼軸方向の任意部位を自動的に撮影することのできる方法を提案している。このものは、眼科撮影装置の撮影系が眼軸方向に移動中、照明光学系のスリット光束投射光軸と角度を持つ光路の観察撮影光学系に付設した位置検知用受光素子に順次入射する反射光を位置検出信号として選択して使用し、予め選択設定した水晶体前面や後面等被検眼の眼軸方向の任意部位の細胞拡大像を撮影することができるようにしたものである。
【０００５】
【発明が解決しようとする課題】
前記のごとく、位置検出指標の角膜反射光が位置する前眼部像から被検部細胞の観察乃至撮影部位を知る場合、例えば角膜内皮細胞の拡大撮影の場合は、前記のごとくして前眼部像を記録した後、撮影系を被検眼方向に移動させて合焦検知用受光素子で角膜内皮合焦が検知されたときの合焦信号で角膜内皮細胞拡大像を記録するため、前眼部像を記録する時点と角膜内皮細胞拡大像を記録する時点との間に時間差を生じ、この間に人間の眼は絶えず固視微動により動いているため、前眼部像における位置検出指標の角膜反射光による光点の位置は、撮影記録された角膜内皮細胞拡大像の前眼部像における位置を正確に表示しないという問題があった。この場合、前記時間差を無くすには、テレビカメラを前眼部用と拡大撮影用と２台使用すれば容易であるが、構造が複雑になる問題がある。
【０００６】
本発明はこのような実情に基づいてなされたものであって、角膜内皮細胞に限らず前記のごとく水晶体上面又は後面等、被検部細胞の拡大像を観察又は撮影する場合、テレビカメラ１台を使用して、被検部細胞のピント合わせを容易に行うことができ、且つ拡大像と共に表示する被検部の撮影部位を示す前眼部像における光点の位置精度を上げることのできる眼科撮影装置を提供することを目的としている。
【０００７】
【課題を解決するための手段】
前記目的を達成するために、本発明の眼科装置に於ては、前眼部観察光学系による前眼部を結像させるためのテレビカメラと、拡大撮影光学系による被検部細胞拡大像を結像させるためのテレビカメラとを兼用するようにして、被検眼に対面して配置された位置検出指標投影光学系と、被検眼にスリット光束を投射するスリット照明光学系と、前眼部観察光学系とその光軸上に受光面を有するテレビカメラを備えた前眼部観察手段と、前眼部照明手段と、被検眼に投射したスリツト照明光に基づき被検部の拡大像を前記前眼部観察光学系と同軸上の前記テレビカメラの結像面に結像させるための拡大撮影光学系を備えた拡大観察手段と、拡大撮影光学系による披検部の合焦を合焦検知用受光素子により検知するようにした被検部の合焦検出手段と、前記位置検出指標投影光学系とスリッ照明光学系と前眼部観察光学系と前眼部照明手段と拡大撮影光学系と合焦検知用受光素子とを有する撮影系全体を被検眼に対し前記観察光学系の光軸に直交する方向と被検眼方向に移動せしめる撮影系移動手段と、前記前眼部観察手段における前眼部像と前記拡大観察手段における被検部の拡大像を記録するための手段とを備え、位置検出指標の被検部からの反射光をテレビカメラの撮像画面上の所定位置に来るごとく前記撮影系を前記観察光学系光軸に直角に移動せしめると共に被検部合焦位置にくるごとく被検眼方向に移動せしめ、被検部の合焦検出手段からの合焦検出信号により被検部細胞の拡大像を記録すると同時に前眼部照明手段を点灯して位置検出指標の被検部反射光による光点の位置する前眼部像を記録するように眼科撮影装置を構成している。
【０００８】
この場合、前記被検部の合焦検出手段からの角膜内皮の合焦検出信号により、被検部角膜内皮細胞の拡大撮影像を記録すると同時に前眼部照明手段を点灯して前眼部像を記録するようにすることも、又は、前記被検部の合焦検出手段からの水晶体上面又は水晶体後面の合焦検出信号、すなわち、眼球面からの第３又は第４の反射光のピークの検出信号により、被検部の水晶体細胞の拡大撮影像を記録すると同時に前眼部照明手段を点灯して前眼部像を記録するようにすることも可能である。
【０００９】
この装置では、位置検出指標の被検部からの反射光をテレビカメラの撮像画面上の所定位置（例えば中央）に来るごとく撮影系を前記前眼部観察光学系光軸に直角方向に移動せしめて被検部との光軸合わせであるアライメントを行うと共に、被検部合焦位置に来るように被検眼方向に移動させて被検部の合焦検出手段からの合焦検出信号により被検部細胞の拡大像を記録すると同時に前眼部照明手段を点灯して位置検出指標の角膜反射光による光点の位置する前眼部像を記録することにより、被検部細胞の拡大像を記録する時点と、位置検出指標の角膜反射光による光点の位置する前眼部像を記録する時点との同一テレビ画面における時間差を最大限無くして、テレビカメラー台で被検部の撮影部位の前眼部像における位置精度を上げることができる。この場合、被検部の合焦信号として角膜内皮合焦信号や水晶体上面又は後面の合焦信号を用いることにより、角膜内皮細胞拡大像や水晶体上面又は後面の細胞拡大像の撮影部位を正確に知ることができる。
【００１０】
【発明の実施の形態】
本発明の実施の形態を添付の図面に基づいて説明する。
図１は、該実施の形態の光路を示す光路で、図２は該実施の形態の電気回路のブロック図である。
【００１１】
図１において、被検眼１の眼球面２をスリット照射するスリット照明光学系と、被検眼に向け撮影光軸位置合わせとともに撮影時の撮影位置検出のための位置検出指標を兼ねるアライメント用指標光を投影してその角膜反射光をテレビカメラ８で撮像するようにした前眼部観察光学系と、該観察光学系と異なる方向から眼球面２に対面して眼球面を照射したスリット照明光に基づき上記テレビカメラ８により被検部の拡大観察乃至拡大写真撮影を行えるようにした拡大撮影光学系とからなる撮影系３が示されており、該撮影系３は、前眼部観察光学系の光軸４に直交する紙面に垂直なＸ方向及び紙面の上下方向であるＹ方向と、観察光学系光軸４の方向であるＺ方向の３方向に、それぞれ後述する駆動機構によって移動させられる。
【００１２】
眼球面２の被検部の照明光源として、拡大撮影光学系によるフォーカシング時に用いる照明ランプ１１と、被検部細胞の拡大撮影時におけるストロボ放電管１３とが、照明ランプ１１の発する光の集光レンズ１２による集束位置とストロボ放電管１３の発する光の集光レンズ１４による集束位置とが同一位置になるように、照明ランプ１１の光はハーフミラー（可視光透過・赤外光反射）１５によりその赤外光が反射される一方、ストロボ放電管１３の光（可視光）は、該ハーフミラー１５を通過してそれぞれスリット１６の位置に集束するように配置されている。この場合、必要に応じ照明ランプ１１と該ハーフミラー１５との間の光路に可視光カットフィルターを挿入し、ストロボ放電管１３と集光レンズ１４との間に赤外光カットフィルターを挿入する。スリット１６を通過した光は投影レンズ１７を通して被検者の眼球１の被観察面である角膜２乃至水晶体を斜方向から、フォーカシング時には照明ランプ１１による照明光により、また撮影時にはストロボ光により、眼軸に対し所定角度で照射するようになっている。
【００１３】
前眼部を観察するための光学系では、眼軸上に位置すべき前眼部観察光学系光軸４上に、前方より順次所定位置にビームスプリッター５、前眼部撮影レンズ６、及び該光軸４と４５°交叉したハーフミラー（赤外光透過、可視光反射）７が配設されて、前眼部撮影レンズ６により後方のテレビカメラ８前面のＣＣＤ受光面９に前眼部像が結像するとともに、後述する装置の光軸合わせを兼ねて被検部の位置表示のための近赤外光が投影結像するようになっている。
【００１４】
また、前記照明光学系の照明光軸１０と前記前眼部観察光学系光軸４を挾んで反対側には、眼球面に対する照明ランプ１１又はストロボ放電管１３による斜めのスリット状照明光線の反射光を受けて角膜内皮等被検部の細胞を拡大観察乃至拡大写真撮影する一方、フォーカシングをするための拡大撮影光学系が設けられ、拡大撮影像が上記テレビカメラ前面のＣＣＤ受光面９及び後述する合焦検知用受光素子３０上に結像するようになっている。すなわち、前眼部撮影用の前眼部観察光学系の光軸４を挾んで照明光学系の照明光軸１０と対称位置にある光軸１８上の所定位置に、眼球面側に対物レンズ１９が、また対物レンズ１９と所定距離をおいてミラー２０が、該光軸１８と所定角度交叉して眼球面からの前記照明光の反射光による像光線を前記前眼部観察光学系光軸４上の所定位置に直交するように折曲げるべく配置され、ミラー２０により反射した像光線は視野絞り２１及び結像レンズ２２を通って上記観察光学系光軸４と４５°交叉したハーフミラー７により拡大像光線のうちストロボ光による可視光は全反射して、テレビカメラ８のＣＣＤ受光面９上に被検部細胞の拡大撮影像として結像するとともに拡大像光線のうち赤外光は該ハーフミラーを通過して後述する合焦検知用受光素子（ＰＳＤ）３０上に結像する。
【００１５】
一方、前記前眼部観察光学系光軸４上のビームスプリッター５に対し該光軸４と直角方向の側方から、被検者に対して固指標を提示するための固指標光と、被検部の位置検出を兼ねて眼軸と前記光軸４とを合致せしめるためのアライメント光である近赤外光とを入射して、これら光線を該前眼部観察光学系光軸４上を進行せしめて眼球面２に入射せしめるようになっている。すなわち、前眼部観察光学系の側方の所定位置に、アライメント光を兼ねた位置検出指標光である近赤外光の発光ダイオード２３と固視標光である明滅可視光の発光ダイオード２４とが、それぞれの光線の光軸が前記観察光学系の光軸４と平行になるように配設され、近赤外線発光ダイオード２３からの近赤外光は集光レンズ２５、ミラー２６、近赤外光反射可視光透過ミラー２７、ミラー２８、集光レンズ２９を通ってビームスプリッター５内の反射面で反射されて前眼部観察光学系光軸４上を眼球面に入射するようになっているとともに、明滅可視光の発光ダイオード２４からの明滅可視光は前記赤外光反射可視光透過ミラー２７を通過し、前記近赤外光と同じくミラー２８、集光レンズ２９、ビームスプリッター５を経て前眼部観察光学系光軸４上を進行し眼球面２に入射するようになっている。
【００１６】
また、前記拡大撮影光学系の光軸１８がミラー２０で折曲げられて前記前眼部観察光学系光軸４と直交する光軸上で、前記テレビカメラ８のＣＣＤ受光面９と、前記前眼部観察光学系光軸４に４５°交叉して配設された前記ハーフミラー７の反射面に関して共役位置に、前記スリット照明光に基づく被検部の合焦を検知するために合焦検知用受光素子（ＰＳＤ）３０が配設されて、前記位置検出指標光兼アライメント指標光の近赤外光と固視標の可視光を被検眼に投影する位置検出指標投影光学系と、前記前眼部観察光学系と前記スリット照明光学系と、前記拡大撮影光学系と前記合焦検知用受光素子３０とからなる撮影系３が被検眼方向に移動するとき前記拡大撮影光学系による角膜上皮、角膜内皮、水晶体上面、水晶体後面の合焦位置を順次検知するようになっている。
【００１７】
そして、テレビカメラ８の結像面であるＣＣＤ受光面９で結像した画像により得られた受像信号は、図２に示す画像入出力制御回路３１に入力する。次に該制御回路３１からの映像信号を受けたモニタ表示器３３の画面に、光軸位置合わせ時には、眼球面２からのアライメント用の近赤外光の反射光による光点が表示され、機械作動の前期段階におけるアライメント状況を確認できるようになっている。
【００１８】
前記画像入出力制御回路３１からの電気信号を受けたＸ・Ｙ方向位置検出回路３４では、撮像画面上の近赤外光によるＸ・Ｙ方向における光点４０（図３参照）の位置を検出し、この位置検出信号をＸ・Ｙ方向位置制御回路３６に入力する。そして、該位置制御回路３６からの制御信号により図３に示す撮像画面上の光点４０が、該画面をＸ方向にＸ_１，Ｘ_２に分割する一方、Ｙ方向にＹ_１，Ｙ_２に２分割した各分割線（点線で表示）の交点である画面中心に位置するように、Ｘ軸駆動機構３８とＹ軸駆動機構３９とを駆動するようになっている。
【００１９】
前記位置検出指標を兼ねる前記アライメント用指標光の角膜反射光による前記撮像画面上の前記の光点４０がほぼ所定の中央付近に来たとき、前記Ｘ・Ｙ方向位置検出回路３４において、前記撮像画面上の前記光点の検出範囲を全画面より上下左右の寸方（Ｘ_１，Ｘ_２，Ｙ_１，Ｙ_２）を縮小してノイズ光に混入を防止する。そして、電気信号をＺ方向位置制御回路３７に入力し、該Ｚ方向位置制御回路３７からの駆動信号でＺ軸駆動機構４４を作動せしめ、撮影系３、具体的には撮影系３を搭載した架台を当初の待機位置より被検眼の眼球面２に向け前進を開始せしめる。この前進開始と同時に照明ランプ１１を点灯して眼球面２を赤外スリット光で照明し、拡大撮影光学系によるフォーカシング開始せしめる。前記撮影系３の被検眼１方向への前進移動の間、アライメント用の近赤外光発光ダイオード２３の点灯と可視光発光ダイオード２４の明滅点灯が行われ、始終動いている被検眼の眼球面２からの反射光による撮像画面上のアライメント用の光点４０が該画面の中心に来るように、撮影系３を搭載した架台はＸ・Ｙ方向に駆動され、該撮影系３は該画面上で該光点を追尾する。
【００２０】
前記撮影系３が被検眼１方向に前進するに伴い、被検眼の眼球面２を含み眼軸上の各眼部からの反射光による拡大像光線（赤外線）が順次拡大撮影光学系から前記合焦検知用受光素子３０に入光し、該受光素子３０からの受光信号がスリット光反射検出回路４１に入力して角膜上皮合焦検出、角膜内皮合焦検出、水晶体上面合焦検出、水晶体後面合焦検出が順次行われる。
【００２１】
眼科撮影装置が、角膜内皮細胞撮影装置の場合、角膜内皮合焦が検出されると、該スリット光反射検出回路４１からの信号がＺ方向位置制御回路３７に入力し、該制御回路３７からの信号でＺ軸駆動機構４４が撮影系３の移動を停止せしめる。また同時に、スリット光反射検出回路４１からの信号でストロボ発光制御回路４２が作動してストロボ放電管１３が発光し被検部からの反射光が拡大撮影光学系の光路を経て被検部の拡大像がテレビカメラ８の受光面９に結像し、テレビカメラ８からの被検部の角膜内皮細胞の拡大像の映像信号は、画像入出力制御回路３１よりフレームメモリ３２に記録される。
【００２２】
この拡大像の記録と同時に、撮影系３前部で前眼部観察光学系の光軸４を挾みスリット照明系光学系と拡大撮影光学系の各光路の外方から前眼部を照明するように配置された赤外線発光ダイオード４５、４５が一瞬点灯して撮像画面上の前記光点とともに前眼部像を画像入出力制御回路３１を介してフレームメモリ３２に記録される。そしてモニタ表示器３３には、前記角膜内皮細胞の拡大像とともに、被検部位に光点が位置している前眼部像が表示される（図４参照）。また、この角膜内皮細胞拡大像と被検部位に光点が位置している前眼部像は、フレームメモリ３２から必要に応じ画像入出力制御回路３１で読み出して、ビデオプリンタ３５から打ち出すことができ、撮影部位を示した被検眼の角膜内皮細胞拡大像の画像プリント（撮影写真）をカルテにつけることができる。この場合、被検部位に光点が位置している前眼部像をモニタ３３上に表示するとき、該光点位置に対応させて、画像入出力制御回路３１により発生させた十字線などの被検部位表示指標を画面上に重ねて表示することにより、他の紛らわしい反射光とも区別でき、被検部位を強調し解り易くすることができる。
【００２３】
一方、撮影系３が前進するとき、その前進移動量は、Z軸に連結されたロータリーエンコーダ等の回転量検出器を含むZ方向移動量検出器４３で連続的に検出される。また、前記スリット光反射検出回路４１からZ方向移動量検出器４３に順次入力した角膜上皮合焦検出信号と角膜内皮検出信号とから、角膜上皮合焦位置から角膜内皮合焦位置までの撮影系３の移動量が、該検出器４３内で演算検出され、算出された移動量すなわち角膜厚の信号は、画像入出力制御回路３１を介してモニタ表示器３３に、角膜内皮細胞拡大像とともに角膜厚として表示することができる。
【００２４】
前記撮影が終了すると、撮影系３は自動的に待機位置へ戻される。すなわち、撮影終了時、画像入出力回路３１からＸＹ方向位置検出回路３４を介してＸＹ方向位置制御回路３６とＺ方向位置制御回路３７からの制御信号により、Ｙ軸駆動機構３９は作動させずＸ軸駆動機構３８とＺ軸駆動機構４４のみを作動せしめ、撮影系３を、Ｘ方向は当初のニュートラル位置へ、また、Ｚ方向は、Ｚ軸を逆駆動して、角膜内皮合焦検知位置より所定の小距離すなわち平均角膜厚の０．５ミリ以上の距離を、Ｚ方向移動量検出器４３からの撮影系の戻り中の移動量の検出信号により検出してＺ方向位置制御回路３７を介して該駆動を制御して初期設定側へ復帰させ、撮影系３を待機状態とする。これにより、被検眼が片方の眼の検眼を終って他の側の眼の検眼を行うとき、Ｘ方向は前の検眼時の位置をそのまま用い、Ｚ方向は、僅かの前進移動だけですむため、機械の操作量を少くして検査時間を短縮することができる。
【００２５】
なお、この眼科撮影装置により、水晶体上面又は水晶体後面を撮影する場合は、前記合焦検知用受光素子（ＰＳＤ）３０における合焦検出信号を第３の合焦検出信号、又は第４の合焦検出信号とすることにより水晶体上面又は後面における被検部細胞の拡大撮影像とともにその撮影部位を前眼部像により知ることができる。
【００２６】
次に、本発明による撮影装置を用いて被検部細胞を拡大撮影する場合の操作手順を、図５に示すフローチャート及び図６に示す被検部細胞の拡大記録と前眼部像記録とのタイミングチャートに基づいて説明する。
先ず撮影系３を、撮影系移動手段のＺ軸駆動機構４４を駆動して被検眼１方向に移動せしめる（ステップ１０１）。この場合、アライメントのため、近赤外線発光ダイオード２３、可視光発光ダイオード２４を点灯せしめ、固視標である可視光発光ダイオード２４からの明滅可視光の固視を被検者に指示しておき、モニタ表示器３３（以下モニタ３３と称す）にテレビカメラ３８からの前眼部像を出さしめる。そして、この撮影系３の被検眼方向への移動により、位置検出指標の被検部からの反射像である光点がモニタ上に検出されると（ステップ１０２）、撮影系移動手段のＺ軸駆動機構４４の駆動は停止し、撮影系３の被検眼方向の移動は停止する（ステップ１０３）。
【００２７】
次いで、前記Ｘ・Ｙ方向位置検出回路３４で位置検出された光点の位置に応じて撮影系移動手段のＸ軸駆動機構３８、Ｙ軸駆動機構３９が駆動されて撮影系３は被検眼の眼軸に直交するＸ・Ｙ方向に移動させられ（ステップ１０４）、位置検出指標の被検部からの反射像すなわち光点が撮像画面上の所定位置（中央）へ移動させられ（図３参照）、該光点が所定の中央付近に来ると（ステップ１０５）、撮影系移動手段のＺ軸駆動機構４４が駆動して撮影系３は被検眼方向に移動せしめられる。（ステップ１０６）。
【００２８】
撮影系３の被検眼方向への移動中、位置検出指標の被検部からの反射像すなわち光点が所定位置でなければ、撮影系３は撮影系移動手段のＸ軸駆動機構、Ｙ軸駆動機構により所定位置方向へ被検眼の眼軸に直交するＸ・Ｙ方向に移動させられる（ステップ１０７）。そして、該光点を撮影画面上で追随しつつ撮影系３は被検部（角膜内皮、水晶体上面又は後面等）の合焦が検出するまで被検眼方向（Z方向）に移動させられ、該被検部の合焦がスリット光反射検出回路４１により検出されると（ステップ１０８）、ストロボ発光制御回路４２が作動してストロボ放電管１３が発光し、テレビカメラ８により被検部細胞の拡大撮影が行われ（ステップ１０９）、撮像された被検部細胞の拡大像がフレームメモリ３２に記録され、同時に、撮影系３の前眼部観察光学系の光軸４の前部側方から前眼部を照明するように配置された赤外線発光ダイオード４５、４５が一瞬点灯して、撮像画面上の前記位置表示を兼ねるアライメント用光点の位置している前眼部像がフレームメモリ３２に記録される（ステップ１１０）。
この場合、合焦検出信号によりストロボが発光するとき、ストロボ発光の次のタイミングでテレビカメラから出力されるフィールド映像信号（細胞像）を記録すると同時に前眼部照明手段を点灯し、前記フイールド映像信号の次のフィールド映像信号（前眼部像）が記録される（図６参照）。
そして、撮影された角膜内皮細胞拡大像４７など被検部細胞の拡大像とともに、位置検出指標の角膜反射光による光点40₁が位置している前眼部像４６がモニタ３３に表示される（図４参頗）。
【００２９】
前記実施の形態では、被検部細胞の拡大像を記録すると同時に前眼部照明手段（撮影系３前部の赤外線発光ダイオード４５、４５）を点灯したが、拡大像記録と同時ではなく被検部細胞の合焦検出と共に点灯し、フレームメモリ３２に、テレビカメラ８による被検部細胞の拡大像記録に連続して前眼部像を記録する等、同時以外のアライメントに邪魔にならない他のタイミングで前眼部照明手段を点灯して、被検部細胞の拡大像記録後、直ちに前記光点の位置する前眼部像を記録することも可能である。
【００３０】
このように、本発明の眼科撮影装置によれは、角膜内皮細胞拡大像や水晶体上面又は後面の細胞拡大像を撮影するに際し、一台のテレビカメラで被検部細胞の拡大像を記録すると同時に前眼部照明手段を点灯して位置検出指標光の角膜反射光による光点の位置する前眼部像を記録することができ、被検部細胞拡大像の撮影部位を正確に知ることができる。
【００３１】
請求項１記載の本発明の眼科撮影装置によれば、被検者の眼球の角膜内皮や水晶体など被検部の細胞を高倍率で拡大観察乃至拡大撮影するとき、一台のテレビカメラを用いて、容易にピント合わせを行って被検部の細胞拡大像を撮影記録すると同時に前眼部照明手段を点灯して撮影位置表示のための光点が位置している前眼部像を共に記録することができるので、被検部細胞拡大像が眼球面のどの部位の細胞像かを位置精度良く知ることができ、眼科での診断に寄与することができる。
【００３２】
請求項２記載の発明によれば、被検部の角膜内皮細胞の拡大像とともに、該拡大像の撮影部位を示す前眼部像上の光点の位置精度の高い前眼部像を記録することのできる眼科撮影装置を提供することができる。
【００３３】
請求項３記載の発明によれば、被検部である水晶体上面又は後面の細胞拡大像とともに、該拡大像の撮影部位を示す前眼部像上の光点の位置精度の高い前眼部像を記録することのできる眼科撮影装置を提供することができる。
【図面の簡単な説明】
【図１】本発明装置の実施の形態の光路図である。
【図２】本発明装置の実施の形態のブロック図である。
【図３】撮像画面と、位置表示を兼ねるアライメント用指標光の角膜反射光による光点との位置関係を示す説明図である。
【図４】角膜内皮細胞拡大像と、光点により撮影部位が示された前眼部像とが表示されたモニタ画面の図である。
【図５】被検部細胞と前眼部像撮影の手順を示すフローチャートである。
【図６】被検部細胞の拡大像記録と前眼部像記録とのタイミングチャートである。
【符号の説明】
１…眼球、２…眼球面（角膜）、３…撮影系、４…前眼部観察光学系光軸、５…ビームスプリッター、６…前眼部撮影レンズ、７…赤外線透過可視光反射ミラー、８…テレビカメラ、９…ＣＣＤ受光面、１０…照明光軸、１１…照明ランプ、１３…ストロボ放電管、１６…スリット、１８…拡大撮影光学系光軸、１９…対物レンズ、２２…結像レンズ、２３…近赤外線発光ダイオード、２４…可視光発光ダイオード、３０…合焦検知用受光素子（ＰＳＤ）、３２…フレームメモリ、３３…モニタ表示器、３４…ＸＹ方向位置検出回路、３８…Ｘ軸駆動機構、３９…Ｙ軸駆動機構、４１…スリット光反射検出回路、４２…ストロボ発光制御回路、４４…Ｚ軸駆動機構、４６…前眼部像、４７…角膜内皮拡大撮影像。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an ophthalmologic photographing apparatus that can accurately know a photographing part in an anterior segment image when photographing a subject cell such as a corneal endothelial cell or a crystalline lens of a subject's eyeball.
[0002]
[Prior art]
It is necessary to observe the state of corneal endothelial cells in order to see the effects of contact lenses and for pre- and post-cataract medical treatments for cataract surgery. Therefore, the objective lens of the microscope is not contacted or contacted with respect to the subject's eye spherical surface, and the slit illumination light is irradiated from the oblique direction with respect to the eye axis toward the observed portion, and the reflected light from the corneal surface An apparatus is used that separates image light rays of endothelial cells and images corneal endothelial cells in a test part with a television camera or the like.
[0003]
When observing or photographing with the above device, the magnified observation photographing part of the cornea is not limited to the central part, but various parts are required depending on the contents of medical treatment. In the prior application No. Hei 5-198951, the applicant can easily focus the endothelial cells of the test part when observing or photographing the corneal endothelial cells of the subject at a high magnification, and We proposed a corneal endothelium imaging device that can determine the position of observation or imaging region. In this case, the imaging system (imaging device) is moved in the X and Y directions with respect to the optical axis of the anterior ocular segment observation optical system provided in the imaging system, and the corneal reflection light of the position detection index projected from the imaging system onto the eye to be examined is The anterior segment image is recorded when the anterior segment image is at a predetermined position on the imaging plane via the observing optical system, and the imaging system is moved in the direction of the subject's eye and the corneal endothelium is focused by the focus detection light receiving element. An enlarged image of corneal endothelial cells is recorded and displayed at the same time with a focus signal at the time of detection.
[0004]
Further, the present applicant has proposed in Japanese Patent Application No. 7-306553 a method capable of automatically photographing an arbitrary part in the axial direction of the eye to be examined such as the upper surface and the rear surface of the crystalline lens without contact. This is a reflection that sequentially enters the light-receiving element for position detection attached to the observation imaging optical system of the optical path having an angle with the slit beam projection optical axis of the illumination optical system while the imaging system of the ophthalmologic imaging apparatus is moving in the direction of the eye axis. The light is selected and used as a position detection signal, and a magnified cell image of an arbitrary part in the eye axis direction of the eye to be examined, such as a pre-selected and set front surface of the crystalline lens, can be taken.
[0005]
[Problems to be solved by the invention]
As described above, in the case of knowing the observation or imaging site of the cell to be examined from the anterior segment image where the corneal reflected light of the position detection index is located, for example, in the case of magnified imaging of corneal endothelial cells, the anterior segment is performed as described above. After recording the partial image, the anterior eye is used to record an enlarged image of the corneal endothelial cell with a focusing signal when the imaging system is moved in the direction of the subject's eye and the focus detection light receiving element detects the corneal endothelial focus. There is a time difference between the time when the partial image is recorded and the time when the enlarged corneal endothelial cell image is recorded. During this time, the human eye constantly moves due to microscopic fixation. There is a problem that the position of the light spot by the reflected light does not accurately display the position in the anterior segment image of the magnified image of corneal endothelial cells that has been photographed and recorded. In this case, in order to eliminate the time difference, it is easy to use two TV cameras for the anterior segment and for the enlarged photographing, but there is a problem that the structure becomes complicated.
[0006]
The present invention has been made based on such a situation, and is not limited to corneal endothelial cells, and as described above, when observing or photographing enlarged images of cells to be examined such as the upper surface or the rear surface of the lens, one television camera is used. Ophthalmology that can easily focus the cells of the test part and increase the position accuracy of the light spot in the anterior segment image showing the imaging part of the test part displayed together with the enlarged image It aims at providing an imaging device.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, in the ophthalmologic apparatus of the present invention, a television camera for imaging the anterior ocular segment by the anterior ocular segment observation optical system and an enlarged image of the cell to be examined by the magnifying optical system are provided. Position detection index projection optical system arranged to face the eye to be used as a television camera for imaging, slit illumination optical system for projecting slit light flux to the eye to be examined, and anterior eye observation Optical system And a TV camera having a light receiving surface on its optical axis Anterior eye observation means; Anterior segment illumination means; Magnified observation optical system for magnifying an image of a portion to be examined on the image plane of the television camera coaxial with the anterior eye portion observation optical system based on slit illumination light projected on the eye to be examined Means, a focus detection means of the test part that detects the focus of the test part by the magnification photographing optical system by the focus detection light receiving element, the position detection index projection optical system, and the slip illumination optical system, Anterior eye observation optical system Anterior segment illumination means and An imaging system moving means for moving the entire imaging system having an enlarged imaging optical system and a focus detection light receiving element in a direction orthogonal to the optical axis of the observation optical system and a direction of the eye to be examined, and the anterior eye portion A means for recording an anterior eye image in the observation means and a means for recording a magnified image of the test part in the magnification observation means, and the reflected light from the test part of the position detection index on the imaging screen of the television camera The imaging system is moved at right angles to the optical axis of the observation optical system as it comes to and moved in the direction of the eye to be examined as it comes to the focus position of the test part, and by the focus detection signal from the focus detection means of the test part Record magnified images of cells in the test area At the same time, turn on the anterior segment illumination means. Position detection index Test part The ophthalmologic photographing apparatus is configured to record an anterior ocular segment image where a light spot by reflected light is located.
[0008]
In this case, an enlarged photographed image of the corneal endothelial cell of the test part is recorded by the focus detection signal of the corneal endothelium from the focus detection means of the test part. At the same time, turn on the anterior segment illumination means. It is also possible to record an anterior ocular segment image, or a focus detection signal of the upper surface of the crystalline lens or the rear surface of the crystalline lens from the in-focus detection means of the test portion, that is, the third or fourth reflection from the spherical surface of the eye. Records magnified images of the lens cells in the test area based on the light peak detection signal At the same time, turn on the anterior segment illumination means. It is also possible to record an anterior segment image.
[0009]
In this apparatus, the imaging system is moved in a direction perpendicular to the optical axis of the anterior ocular segment observation optical system so that the reflected light from the test part of the position detection index comes to a predetermined position (for example, the center) on the imaging screen of the TV camera. The optical axis alignment with the test part is performed, and the test part is moved in the direction of the eye so that it comes to the focus position of the test part, and the test is performed by the focus detection signal from the focus detection means of the test part. A magnified image of human cells At the same time, turn on the anterior segment illumination means. By recording the anterior segment image where the light spot is located by the corneal reflection light of the position detection index, the time point when the enlarged image of the cell to be examined is recorded, and before the position of the light spot by the corneal reflection light of the position detection index The time difference on the same television screen from the time when the eye image is recorded can be eliminated to the maximum, and the position accuracy in the anterior eye image of the imaging region of the test part can be increased with the television camera stand. In this case, by using the corneal endothelium focusing signal or the focusing surface signal of the upper surface or the back surface of the lens as the focusing signal of the test part, the imaging part of the enlarged corneal endothelial cell image or the enlarged cell image of the upper surface or the back surface of the lens can be accurately determined. I can know.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is an optical path showing an optical path of the embodiment, and FIG. 2 is a block diagram of an electric circuit of the embodiment.
[0011]
In FIG. 1, a slit illumination optical system for slit-irradiating an eye spherical surface 2 of an eye 1 to be examined, and alignment index light that also serves as a position detection index for photographing position detection at the time of photographing while aligning the photographing optical axis toward the subject eye. Based on the anterior ocular segment observation optical system that projects the corneal reflection light by the television camera 8 and the slit illumination light that is directed to the eye spherical surface 2 from a different direction from the observation optical system and that irradiates the eye spherical surface. An imaging system 3 is shown that includes an enlarged imaging optical system that enables the television camera 8 to perform magnified observation or magnified photography of the test portion. The imaging system 3 is a light beam of the anterior ocular segment observation optical system. It is moved by a driving mechanism, which will be described later, in three directions: an X direction perpendicular to the paper surface perpendicular to the axis 4, a Y direction that is the vertical direction of the paper surface, and a Z direction that is the direction of the observation optical system optical axis 4.
[0012]
As an illumination light source for the test portion of the eye spherical surface 2, the illumination lamp 11 used during focusing by the magnifying imaging optical system and the strobe discharge tube 13 used when the test subject cell is magnified are collected by the illumination lamp 11. The light from the illumination lamp 11 is reflected by a half mirror (visible light transmission / infrared light reflection) 15 so that the converging position by the lens 12 and the converging position of the light emitted from the strobe discharge tube 13 by the condensing lens 14 are the same position. While the infrared light is reflected, the light (visible light) of the stroboscopic discharge tube 13 is arranged so as to pass through the half mirror 15 and be focused at the position of the slit 16. In this case, a visible light cut filter is inserted in the optical path between the illumination lamp 11 and the half mirror 15 as necessary, and an infrared light cut filter is inserted between the strobe discharge tube 13 and the condenser lens 14. The light that has passed through the slit 16 passes through the projection lens 17 from the oblique direction of the cornea 2 or the crystalline lens, which is the observation surface of the subject's eyeball 1, by illumination light from the illumination lamp 11 during focusing, and by strobe light during imaging. Irradiation is performed at a predetermined angle with respect to the axis.
[0013]
In the optical system for observing the anterior segment, on the anterior segment observing optical system optical axis 4 to be positioned on the optic axis, the beam splitter 5, the anterior segment imaging lens 6, A half mirror (infrared light transmission, visible light reflection) 7 crossing the optical axis 4 and 45 ° is arranged, and the anterior segment image is formed on the CCD light receiving surface 9 on the front surface of the rear TV camera 8 by the anterior segment imaging lens 6. Is imaged, and near-infrared light for displaying the position of the portion to be examined is projected and imaged to serve as the optical axis alignment of the apparatus described later.
[0014]
Further, on the opposite side of the illumination optical axis 10 of the illumination optical system and the optical axis 4 of the anterior ocular segment observation optical system, an oblique slit-shaped illumination beam is reflected by the illumination lamp 11 or the strobe discharge tube 13 with respect to the spherical surface of the eye. In response to receiving light, the cells in the test part such as the corneal endothelium are magnified or photographed, and a magnified optical system for focusing is provided. An image is formed on the focus detection light receiving element 30. That is, with the optical axis 4 of the anterior ocular segment observation optical system for photographing the anterior ocular segment, the objective lens 19 is placed on the eye spherical side at a predetermined position on the optical axis 18 that is symmetrical to the illumination optical axis 10 of the illumination optical system. However, the mirror 20 at a predetermined distance from the objective lens 19 crosses the optical axis 18 at a predetermined angle to convert the image light beam by the reflected light of the illumination light from the eye spherical surface to the optical axis 4 of the anterior ocular segment observation optical system. The image beam reflected by the mirror 20 is arranged to be bent so as to be orthogonal to the predetermined position above, and passes through the field stop 21 and the imaging lens 22 by the half mirror 7 crossing the observation optical system optical axis 4 by 45 °. Visible light by the stroboscopic light among the magnified image rays is totally reflected and formed on the CCD light receiving surface 9 of the television camera 8 as a magnified image of the cell to be examined, and the infrared light among the magnified image rays is the half of the magnified image rays. Focus detection described later through the mirror On a light receiving element (PSD) 30 on.
[0015]
On the other hand, from the side perpendicular to the optical axis 4 with respect to the beam splitter 5 on the optical axis 4 of the anterior ocular segment observation optical system, a fixed index light for presenting a fixed index to the subject, Near-infrared light, which is alignment light for aligning the eye axis with the optical axis 4 for detecting the position of the detection part, is incident, and these light rays are incident on the optical axis 4 of the anterior eye observation optical system. It is made to advance and enter the eye spherical surface 2. That is, at a predetermined position on the side of the anterior ocular segment observation optical system, a near-infrared light emitting diode 23 that is position detection index light that also serves as alignment light, and a flickering visible light emitting diode 24 that is fixation target light, However, the optical axes of the respective light beams are arranged so as to be parallel to the optical axis 4 of the observation optical system, and the near infrared light from the near infrared light emitting diode 23 is collected by the condenser lens 25, the mirror 26, the near infrared light. The light is reflected by the reflection surface in the beam splitter 5 through the light reflection visible light transmission mirror 27, the mirror 28, and the condenser lens 29, and is incident on the eyeball surface on the optical axis 4 of the anterior ocular segment observation optical system. At the same time, the blinking visible light from the light emitting diode 24 of the blinking visible light passes through the infrared light reflection visible light transmission mirror 27 and passes through the mirror 28, the condensing lens 29, and the beam splitter 5 in the same manner as the near infrared light. Eye observation light It is incident on the eyeball surface 2 travels through the system optical axis 4 above.
[0016]
Further, the optical axis 18 of the magnification photographing optical system is bent by a mirror 20, and the CCD light receiving surface 9 of the television camera 8 and the front surface are arranged on an optical axis orthogonal to the optical axis 4 of the anterior ocular segment observation optical system. Focus detection for detecting the focus of the test part based on the slit illumination light at a conjugate position with respect to the reflection surface of the half mirror 7 disposed 45 ° across the optical axis 4 of the eye observation optical system A position detection index projection optical system for projecting near-infrared light of the position detection index light and alignment index light and visible light of the fixation target onto the eye to be examined; A corneal epithelium formed by the magnifying imaging optical system when the imaging system 3 including the eye observation optical system, the slit illumination optical system, the magnifying imaging optical system, and the focus detection light receiving element 30 moves in the direction of the eye to be examined; Focus position of corneal endothelium, lens upper surface, lens rear surface It is adapted to the next detection.
[0017]
Then, the received image signal obtained from the image formed on the CCD light receiving surface 9 which is the image forming surface of the television camera 8 is input to the image input / output control circuit 31 shown in FIG. Next, on the screen of the monitor display 33 that has received the video signal from the control circuit 31, when the optical axis is aligned, the light spot by the reflected light of the near-infrared light for alignment from the eye spherical surface 2 is displayed. The alignment status in the first stage of operation can be confirmed.
[0018]
The X / Y direction position detection circuit 34 that has received the electrical signal from the image input / output control circuit 31 detects the position of the light spot 40 (see FIG. 3) in the X / Y direction by near infrared light on the imaging screen. Then, this position detection signal is input to the X / Y direction position control circuit 36. Then, the light spot 40 on the imaging screen shown in FIG. 3 causes the screen to move in the X direction in accordance with the control signal from the position control circuit 36. ₁ , X ₂ While Y in the Y direction ₁ , Y ₂ The X-axis drive mechanism 38 and the Y-axis drive mechanism 39 are driven so as to be positioned at the center of the screen, which is the intersection of the respective divided lines (indicated by dotted lines).
[0019]
When the light spot 40 on the imaging screen due to the corneal reflected light of the alignment index light that also serves as the position detection index is approximately near a predetermined center, the X / Y direction position detection circuit 34 performs the imaging. The detection range of the light spot on the screen is the vertical and horizontal dimensions (X ₁ , X ₂ , Y ₁ , Y ₂ ) To reduce noise light. Then, an electric signal is input to the Z direction position control circuit 37 and the Z axis drive mechanism 44 is operated by the drive signal from the Z direction position control circuit 37, and the photographing system 3, specifically, the photographing system 3 is mounted. The advancement is started from the initial standby position toward the eye spherical surface 2 of the eye to be examined. Simultaneously with the start of the forward movement, the illumination lamp 11 is turned on to illuminate the eyeball surface 2 with infrared slit light, and the focusing by the enlarged photographing optical system is started. During the forward movement of the imaging system 3 in the direction of the eye 1 to be examined, the alignment near-infrared light-emitting diode 23 is turned on and the visible light-emitting diode 24 is blinked, and the eye spherical surface of the eye to be examined is moved all the time. The gantry mounted with the imaging system 3 is driven in the X and Y directions so that the alignment light spot 40 on the imaging screen due to the reflected light from 2 is at the center of the screen, and the imaging system 3 is on the screen. To track the light spot.
[0020]
As the imaging system 3 moves forward in the direction of the eye 1 to be examined, magnified image rays (infrared rays) due to reflected light from each eye part including the eye spherical surface 2 of the eye to be examined are sequentially transmitted from the magnification photographing optical system. Light is incident on the focus detection light receiving element 30 and a light reception signal from the light receiving element 30 is input to the slit light reflection detection circuit 41 to detect corneal epithelial focus detection, corneal endothelium focus detection, lens top surface focus detection, lens back surface Focus detection is performed sequentially.
[0021]
When the ophthalmologic photographing apparatus is a corneal endothelial cell photographing apparatus, when the corneal endothelium focusing is detected, a signal from the slit light reflection detection circuit 41 is input to the Z-direction position control circuit 37 and the control circuit 37 The signal causes the Z-axis drive mechanism 44 to stop the movement of the photographing system 3. At the same time, the strobe light emission control circuit 42 is actuated by a signal from the slit light reflection detection circuit 41 so that the strobe discharge tube 13 emits light, and the reflected light from the test part passes through the optical path of the magnifying optical system to enlarge the test part. An image is formed on the light receiving surface 9 of the television camera 8, and a video signal of an enlarged image of the corneal endothelial cell of the test portion from the television camera 8 is recorded in the frame memory 32 by the image input / output control circuit 31.
[0022]
Simultaneously with the recording of the magnified image, the anterior eye portion is illuminated from the outside of each optical path of the slit illumination optical system and the magnified photographing optical system by holding the optical axis 4 of the anterior ocular segment observation optical system at the front part of the photographing system 3. The infrared light emitting diodes 45, 45 arranged in this manner are lit momentarily, and the anterior segment image is recorded in the frame memory 32 via the image input / output control circuit 31 together with the light spot on the imaging screen. The monitor display 33 displays an image of the anterior segment of the eye where the light spot is located at the site to be examined along with the magnified image of the corneal endothelial cells (see FIG. 4). Further, the enlarged image of the corneal endothelial cell and the anterior ocular segment image where the light spot is located at the test site can be read out from the frame memory 32 by the image input / output control circuit 31 as needed and ejected from the video printer 35. In addition, an image print (photographed photograph) of a magnified image of the corneal endothelial cell of the eye to be examined showing the imaging region can be attached to the chart. In this case, when the anterior segment image in which the light spot is located at the site to be examined is displayed on the monitor 33, a cross line or the like generated by the image input / output control circuit 31 corresponding to the light spot position is displayed. By displaying the test site display index in an overlapping manner on the screen, it can be distinguished from other confusing reflected light, and the test site can be emphasized and easily understood.
[0023]
On the other hand, when the photographing system 3 moves forward, the forward movement amount is continuously detected by a Z direction movement amount detector 43 including a rotation amount detector such as a rotary encoder connected to the Z axis. Further, from the corneal epithelial focus detection signal and the corneal endothelium detection signal sequentially input from the slit light reflection detection circuit 41 to the Z-direction movement amount detector 43, the cornea Up The movement amount of the imaging system 3 from the skin focusing position to the corneal endothelium focusing position is calculated and detected in the detector 43, and the calculated movement amount, that is, the corneal thickness signal is passed through the image input / output control circuit 31. The corneal endothelial cell enlarged image can be displayed on the monitor display 33 as the corneal thickness.
[0024]
When the photographing is finished, the photographing system 3 is automatically returned to the standby position. That is, at the end of shooting, the Y-axis drive mechanism 39 is not operated by the control signal from the XY direction position control circuit 36 and the Z direction position control circuit 37 from the image input / output circuit 31 via the XY direction position detection circuit 34. Only the shaft drive mechanism 38 and the Z-axis drive mechanism 44 are operated, and the imaging system 3 is moved to the initial neutral position in the X direction, and in the Z direction, the Z axis is reversely driven from the corneal endothelium focus detection position. A predetermined small distance, that is, a distance of 0.5 mm or more of the average corneal thickness is detected by the detection signal of the movement amount during returning of the photographing system from the Z direction movement amount detector 43 and is passed through the Z direction position control circuit 37. Then, the driving is controlled to return to the initial setting side, and the photographing system 3 is set in a standby state. As a result, when the eye to be examined finishes the eye examination of one eye and the eye of the other side is examined, the X direction uses the position at the time of the previous eye examination as it is, and the Z direction only requires a slight forward movement. The inspection time can be shortened by reducing the operation amount of the machine.
[0025]
When the ophthalmologic photographing apparatus is used to photograph the upper surface of the crystalline lens or the rear surface of the crystalline lens, the focus detection signal in the focus detection light receiving element (PSD) 30 is used as the third focus detection signal or the fourth focus. By using the detection signal, it is possible to know the imaged region of the to-be-examined cell on the upper surface or the rear surface of the lens together with the anterior eye image.
[0026]
Next, an operation procedure in the case of enlarging an image of a test part cell using the imaging apparatus according to the present invention will be described with reference to the flowchart shown in FIG. 5 and the enlarged recording of the test part cell and the anterior segment image recording shown in FIG. This will be described based on the timing chart.
First, the imaging system 3 is moved in the direction of the eye 1 by driving the Z-axis drive mechanism 44 of the imaging system moving means (step 101). In this case, for alignment, the near-infrared light emitting diode 23 and the visible light emitting diode 24 are turned on, and the subject is instructed to fix the blinking visible light from the visible light emitting diode 24 which is a fixation target. An anterior segment image from the television camera 38 is displayed on the monitor display 33 (hereinafter referred to as the monitor 33). When the light spot, which is a reflection image of the position detection index from the test portion, is detected on the monitor by the movement of the photographing system 3 in the direction of the eye to be examined (step 102), the Z axis of the photographing system moving means The drive of the drive mechanism 44 is stopped, and the movement of the imaging system 3 in the direction of the eye to be examined is stopped (step 103).
[0027]
Next, the X-axis drive mechanism 38 and the Y-axis drive mechanism 39 of the imaging system moving means are driven according to the position of the light spot whose position is detected by the X / Y direction position detection circuit 34, and the imaging system 3 is connected to the eye to be examined. It is moved in the X and Y directions orthogonal to the eye axis (step 104), and the reflected image of the position detection index, that is, the light spot is moved to a predetermined position (center) on the imaging screen (see FIG. 3). ) When the light spot comes near a predetermined center (step 105), the Z-axis drive mechanism 44 of the imaging system moving means is driven and the imaging system 3 is moved in the direction of the eye to be examined. (Step 106).
[0028]
When the imaging system 3 is moving in the direction of the eye to be examined, if the reflected image of the position detection index from the test portion, that is, the light spot is not a predetermined position, the imaging system 3 is an X-axis drive mechanism, Y-axis drive of the imaging system moving means. The mechanism is moved in the X and Y directions orthogonal to the eye axis of the eye to be examined in a predetermined position direction (step 107). The imaging system 3 is moved in the direction of the eye to be examined (Z direction) until the focus of the part to be examined (corneal endothelium, lens upper surface or rear surface, etc.) is detected while following the light spot on the imaging screen, When the focus of the test part is detected by the slit light reflection detection circuit 41 (step 108), the strobe light emission control circuit 42 is actuated and the strobe discharge tube 13 emits light, and the TV camera 8 enlarges the test part cell. Photographing is performed (step 109), and a magnified image of the captured cell to be examined is recorded in the frame memory 32, and at the same time, the anterior view from the front side of the optical axis 4 of the anterior ocular segment observation optical system of the photographing system 3 is recorded. Infrared light emitting diodes 45, 45 arranged to illuminate the eye part are lit momentarily, and an anterior eye part image in which the alignment light spot that also serves as the position display on the imaging screen is recorded in the frame memory 32. The (Step 110).
In this case, when the strobe light is emitted by the focus detection signal, the field image signal (cell image) output from the TV camera is recorded at the next timing of the strobe light emission and at the same time the anterior segment illumination means Is turned on, and the next field video signal (anterior eye image) of the field video signal is recorded (see FIG. 6).
Then, together with the magnified image of the subject cell such as the photographed magnified corneal endothelial cell image 47, the light spot 40 by the corneal reflection light of the position detection index. ₁ The anterior eye part image 46 in which is located is displayed on the monitor 33 (see FIG. 4).
[0029]
In the above-described embodiment, the anterior segment illumination means (infrared light emitting diodes 45, 45 at the front of the imaging system 3) is turned on simultaneously with recording an enlarged image of the cell to be examined. Other than that which does not interfere with the alignment other than simultaneous, such as recording an anterior segment image in the frame memory 32 continuously with the magnified image recording of the subject cell by the TV camera 8. It is also possible to record the anterior segment image where the light spot is located immediately after recording the enlarged image of the cell to be examined by turning on the anterior segment illumination means at the timing.
[0030]
As described above, according to the ophthalmologic photographing apparatus of the present invention, when a magnified image of corneal endothelial cells and a magnified image of the upper surface or the rear surface of the crystalline lens are photographed, the magnified image of the cells to be examined with a single television camera. The Record At the same time, turn on the anterior segment illumination means. It is possible to record the anterior segment image where the light spot is located by the corneal reflection light of the position detection index light, and it is possible to accurately know the imaging region of the enlarged cell image of the test part.
[0031]
According to the ophthalmologic photographing apparatus of the present invention as set forth in claim 1, when observing or magnifying a cell of a test part such as a corneal endothelium or a crystalline lens of a subject's eye at a high magnification, a single television camera is used. And focus easily to enlarge the cell image of the test area The Shooting record At the same time, turn on the anterior segment illumination means. Since the anterior segment image where the light spot for displaying the imaging position is recorded can be recorded together, it is possible to know with high positional accuracy which part of the eye spherical surface the magnified image of the cell of the test area. Can contribute to diagnosis in ophthalmology.
[0032]
According to the second aspect of the present invention, an anterior ocular segment image with high positional accuracy of the light spot on the anterior ocular segment image indicating the imaging part of the magnified image is recorded together with the magnified image of the corneal endothelial cell of the test area. It is possible to provide an ophthalmologic photographing apparatus capable of performing the above.
[0033]
According to the invention of claim 3, an anterior ocular segment image with high positional accuracy of a light spot on an anterior ocular segment image indicating a photographing part of the magnified image, together with a cell magnified image of the upper surface or the posterior surface of the crystalline lens that is a test portion Can be provided.
[Brief description of the drawings]
FIG. 1 is an optical path diagram of an embodiment of the apparatus of the present invention.
FIG. 2 is a block diagram of an embodiment of the apparatus of the present invention.
FIG. 3 is an explanatory diagram showing a positional relationship between an imaging screen and a light spot by corneal reflection light of alignment index light also serving as position display;
FIG. 4 is a diagram of a monitor screen on which an enlarged image of corneal endothelial cells and an anterior ocular segment image in which an imaging region is indicated by a light spot are displayed.
FIG. 5 is a flowchart showing a procedure for photographing a test part cell and an anterior segment image.
FIG. 6 is a timing chart of enlarged image recording and anterior eye image recording of a subject cell.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Eyeball, 2 ... Eye spherical surface (cornea), 3 ... Imaging system, 4 ... Optical axis of anterior ocular segment observation optical system, 5 ... Beam splitter, 6 ... Anterior ocular segment imaging lens, 7 ... Infrared transmission visible light reflection mirror, DESCRIPTION OF SYMBOLS 8 ... Television camera, 9 ... CCD light-receiving surface, 10 ... Illumination optical axis, 11 ... Illumination lamp, 13 ... Strobe discharge tube, 16 ... Slit, 18 ... Optical axis of enlarged photographing optical system, 19 ... Objective lens, 22 ... Imaging Lens: 23 ... Near-infrared light emitting diode, 24 ... Visible light emitting diode, 30 ... Focus detection light receiving element (PSD), 32 ... Frame memory, 33 ... Monitor display, 34 ... XY direction position detection circuit, 38 ... X Axis drive mechanism, 39 ... Y-axis drive mechanism, 41 ... Slit light reflection detection circuit, 42 ... Strobe light emission control circuit, 44 ... Z-axis drive mechanism, 46 ... Anterior eye part image, 47 ... Corneal endothelium enlarged image.

Claims

A position detection index projection optical system arranged facing the eye to be examined, a slit illumination optical system for projecting a slit light beam to the eye to be examined, an anterior ocular segment observation optical system, and a television camera having a light receiving surface on its optical axis An anterior ocular segment observing means, an anterior ocular segment illuminating unit, and an enlarged image of the test area based on slit illumination light projected on the eye to be inspected. Magnifying observation means provided with a magnifying optical system for forming an image on the subject, and a focus detection means for the part to be inspected, which is detected by a focus detection light receiving element by the magnifying optical system An entire imaging system including the position detection index projection optical system, the slit illumination optical system, the anterior ocular segment observation optical system, the anterior ocular segment illumination means, the magnifying imaging optical system, and the focus detection light receiving element. Move in the direction perpendicular to the optical axis of the observation optical system and the direction of the eye to be examined Imaging system moving means, and means for recording an anterior eye part image in the anterior eye part observing means and a magnified image of the part to be examined in the magnifying observation means, and reflection of a position detection index from the part to be examined. Move the imaging system in a direction perpendicular to the optical axis of the observation optical system as the light comes to a predetermined position on the imaging screen of the TV camera, and move it in the direction of the eye to be examined as it comes to the focus position of the test part. An enlarged image of the cell to be examined is recorded by a focus detection signal from the focus detection means, and at the same time the anterior eye illumination means is turned on, and the anterior eye part where the light spot is located by the reflected light of the test part of the position detection index An ophthalmologic photographing apparatus characterized by recording an image.

In accordance with the focus detection signal of the corneal endothelium from the focus detection means of the test part, an enlarged photographed image of the corneal endothelial cell of the test part is recorded , and at the same time, the anterior segment illumination means is turned on to record the anterior eye part image. The ophthalmic photographing apparatus according to claim 1, wherein:

An anterior ocular segment illuminating unit is turned on at the same time as an enlarged photographed image of the lens cell of the test unit is recorded by a focus detection signal on the upper surface of the lens or the rear surface of the crystalline lens from the focus detection unit of the test unit. The ophthalmologic photographing apparatus according to claim 1, wherein: