JP4128405B2 - Microscope imaging device - Google Patents

Description

が得られる。ここでｘは画像の水平方向の位置、ｙは画像の垂直方向の位置、Ｎｘは画像の水平方向の画素数、Ｎｙは画像の垂直方向の画素数、ｕは水平方向の空間周波数、ｖは垂直方向の空間周波数、ｊは虚数である。
【００４５】
次に、ステップ３０３で、（１）式よりＩ(０,０)、つまり直流成分から画像の明るさを求め、予め設定した閾値Ｌ１と比較する。
【００４６】
この場合、具体例を上げて説明すると、例えば、明視野観察（または位相差観察）のような明るい標本の撮影画像と、蛍光観察（または暗視野観察）のような暗い標本の撮影画像のそれぞれについて輝度画像を求め、これら輝度画像のフーリエ変換の結果を図示すると、図４中の（ａ）、（ｂ）のように表わすことができる。ここで、（ａ）は、明視野観察（または位相差観察）の場合、（ｂ）は、蛍光観察（または暗視野観察）の場合を示している。また、同図の横軸は、周波数で、サンプリング周波数が１、ナイキスト周波数が０．５の場合を示している。なお、図５は、図４の一部分のみを拡大して示すものである。
【００４７】
そして、このような図４（図５）の（ａ）（ｂ）に示す結果からＩ(０,０)、つまり直流成分から画像の明るさとしてＬａ、Ｌｂを求め、これらＬａ、Ｌｂについて、閾値Ｌ１と比較する。
【００４８】
この場合、閾値Ｌ１は、明るい標本の撮影画像と暗い標本の撮影画像の判定基準となるもので、Ｌａ、Ｌｂとの間に設定される。これにより、閾値Ｌ１に対してＬａ、Ｌｂが大きいか小さいかを判断することで、明視野観察（または位相差観察）の撮影画像であるか、蛍光観察（または暗視野観察）の撮影画像であるかを判断することが可能になる。
【００４９】
ここで、Ｉ(０,０)がＬ１より小さい場合、例えば、図４（図５）に示すＬｂの場合は、蛍光観察（または暗視野観察）による暗い撮影画像と判断され、ステップ３０４に進む。ステップ３０４では、階調特性設定部３０により、階調特性パラメータとして図２（ｂ）に示すような階調特性Ｂが階調補正処理部２８に設定され、同時に、色補正パラメータ設定部２９により階調特性Ｂに最適な色変換マトリックスＢが色補正処理部２７に設定される。そして、これらの設定にしたがって信号処理部２５で画像データの処理が行われる。
【００５０】
この場合、蛍光観察（または暗視野観察）による撮影画像は、輝度分布が暗い部分から明るい部分まで分布しており、ここに図２（ｂ）に示すような階調特性Ｂを用いることにより、輝度分布を平均的に表現できるようになる。
【００５１】
一方、ステップ３０３で、Ｉ(０,０)がＬ１より大きい場合、例えば、図４（図５）に示すＬａの場合は、明視野観察（または位相差観察）による明るい撮影画像と判断され、ステップ３０５に進む。
【００５２】
ステップ３０５では、（１）式よりＩ（ｕ，０）／Ｉ（０，０）の
０．０５＜（ｕ／Ｎｘ）＜０．２の和
【数２】

を求める。
【００５３】
この結果は、実際に求められる傾向からして画像のコントラストとして評価することができる。そして、この結果を、ステップ３０６、３０７で予め設定した閾値Ｌ２、Ｌ３と比較する。
【００５４】
この場合も具体例を上げて説明すると、例えば、高コントラスト標本の撮像画像と低コントラスト標本の撮像画像について、それぞれの輝度画像を求め、これら輝度画像のフーリエ変換の結果を図示すると、図６中の（ａ）、（ｂ）のように表わすことができる。ここで、（ａ）は、高コントラスト標本の場合、（ｂ）は、低コントラスト標本の場合を示している。そして、これら図６（ａ）、（ｂ）に示す結果から、Ｉ（ｕ，０）／Ｉ（０，０）の
０．０５＜（ｕ／Ｎｘ）＜０．２の和、つまり（２）式から、それぞれＬｃ、Ｌｄを求め、これらＬｃ、Ｌｄについて、閾値Ｌ２、Ｌ３と比較する。
【００５５】
閾値Ｌ２は、これ以下を低コントラスト画像と判断するための値、閾値Ｌ３は、これ以上を高コントラスト画像と判断するための値で、これら閾値Ｌ２、Ｌ３に対してＬｃ、Ｌｄが大きいか小さいかを判断することで、低コントラスト画像、高コントラスト画像およびこれらの中間画像を３段階で判断できるようにしている。ここでは、閾値Ｌ２は、Ｌｃ＞Ｌ２＞Ｌｄ、閾値Ｌ３は、Ｌｃ＞Ｌ３に設定されているものとする。
【００５６】
これにより、いま、図６（ｂ）に示す低コントラスト標本の撮影画像に対応するＬｄの場合、ステップ３０６で、閾値Ｌ２より小さく低コントラスト画像と判断され、ステップ３０８に進む。ステップ３０８では、階調特性設定部３０により、階調特性パラメータとして図２（ｃ）に示すような階調特性Ｃが階調補正処理部２８に設定され、同時に、色補正パラメータ設定部２９により階調特性Ｃに最適な色変換マトリックスＡが色補正処理部２７に設定される。そして、これらの設定にしたがって信号処理部２５で画像データの処理が行われる。
【００５７】
この場合、コントラストが低い画像は、画像の輝度分布が明るいところに集中していると考えられるので、図２（ｃ）に示すような階調特性Ｃと、この階調特性Ｃに対応した色変換マトリックスＣを選択することにより、コントラストを大きくして画像を表現できるようになる。
【００５８】
また、図６（ａ）に示す高コントラスト標本の撮影画像に対応するＬｃの場合、ステップ３０６で、閾値Ｌ２より大きいと判断され、ステップ３０７に進む。そして、ステップ３０７で、閾値Ｌ３よりさらに大きく高コントラスト画像と判断され、ステップ３０９に進む。ステップ３０９では、階調特性設定部３０により、階調特性パラメータとして図２（ａ）に示すような階調特性Ａが階調補正処理部２８に設定され、同時に、色補正パラメータ設定部２９により階調特性Ａに最適な色変換マトリックスＡが色補正処理部２７に設定される。そして、これらの設定にしたがって信号処理部２５で画像データの処理が行われる。
【００５９】
この場合、コントラストが高い画像は、明視野観察では標本のない照明光のみが透過してくる明るい部分と、標本のある暗い部分が分布していると考えられるので、図２（ａ）に示すような階調特性Ａと、この階調特性Ａに対応した色変換マトリックスＡを選択することにより、画像上の注目部分である比較的暗い標本部分のコントラストを広げ、かつ明るい照明部分まで表現できるようになる。
【００６０】
さらに、具体例として挙げていないが、例えば、図６（ａ）（ｂ）に示す撮影画像の中間に位置するコントラストの撮影画像の場合は、ステップ３０６で、閾値Ｌ２より大きいと判断されるが、ステップ３０７で、閾値Ｌ３より小さいく中間コントラスト画像と判断され、ステップ３１０に進む。ステップ３１０では、階調特性設定部３０により、階調特性パラメータとして図２（ｂ）に示すような階調特性Ｂが階調補正処理部２８に設定され、同時に、色補正パラメータ設定部２９により階調特性Ｂに最適な色変換マトリックスＢが色補正処理部２７に設定される。そして、これらの設定にしたがって信号処理部２５で画像データの処理が行われる。
【００６１】
この場合、コントラストが中間の画像は、画像の輝度分布が一様に広がっていると考えられるため、図２（ｂ）に示すような階調特性Ｂと、この階調特性Ｂに対応した色変換マトリックスＢを選択することで、観察像を良好に表現できるようになる。
【００６２】
従って、このようにすれば、撮像素子２１で撮像した画像データの空間周波数解析の結果に基づいて、顕微鏡１での検鏡法を判断できるとともに、画像データのコントラストに応じた階調補正処理部２８での階調特性および色補正処理部２７での色補正パラメータの設定により、画像の状態に最適な階調補正処理および色補正処理を行うことができるので、透過明視野観察や蛍光観察など各種検鏡法を切替え可能にした顕微鏡に適用される場合も、操作者が特別な操作をすることなく、観察標本に最適な階調補正処理および色補正処理を行うことができ、常に観察している標本を最適に表現する良好な画像を取得することができる。
【００６３】
なお、上述した実施の形態で説明した空間周波数解析の結果と選択した階調特性、色変換マトリックスを、撮像した標本画像と共に表示部３２に表示したり、記録部３５に記録するようにしてもよい。こうすれば、操作者がどのようなパラメータが設定されたか確認することができるので、より一層使い勝手のよい顕微鏡用撮像装置を提供できる。
【００６４】
（第２の実施の形態）
次に、本発明の第２の実施の形態について説明する。
【００６５】
図７は、本発明の第２の実施の形態の概略構成を示すもので、図１と同一部分には、同符号を付している。
【００６６】
この場合、Ａ／Ｄ変換部２４には、信号処理部２５および空間周波数解析部２６が接続されている。信号処理部２５は、色補正処理部２７と階調補正処理部２８の他に、輪郭強調処理手段としての輪郭強調処理部４１を有している。輪郭強調処理部４１は、図８に示すようにエッジ抽出部４１１、ゲイン調整部４１２、輪郭強調部４１３からなっている。この場合、Ａ／Ｄ変換部２４から輪郭強調処理部４１へ入力された画像データは、エッジ抽出部４１１でバンドパスフィルタをかけられエッジが抽出される。また、この抽出されたエッジ成分に、ゲイン調整部４１２でゲインをかけ、輪郭強調部４１３で階調補正処理部２８から入力される画像データに加えられ、バス３３を介して制御部３４に送り出される。
【００６７】
空間周波数解析部２６には、輪郭強調処理パラメータ設定手段としての輪郭強調処理パラメータ設定部４２が接続されている。輪郭強調処理パラメータ設定部４２は、処理パラメータとして、より低い輪郭強調ゲインＡとより高い輪郭強調ゲインＢを記憶しており、空間周波数解析部２６での解析結果に基づいて、輪郭強調処理部４１のゲイン調整部４１２に対して輪郭強調ゲインＡまたは輪郭強調ゲインＢを設定する。
【００６８】
制御部３４には、Ｉ／Ｆ部４３を介してパーソナルコンピュータ(以下ＰＣと略称する。)４４が接続されている。このＰＣ４４は、図１で述べた表示部３２、記録部３５、操作部３６のそれぞれの機能を有している。
【００６９】
このような構成において、Ａ／Ｄ変換部２４から空間周波数解析部２６へデジタル変換された画像データが入力されると、信号処理部２５、空間周波数解析部２６および輪郭強調処理パラメータ設定部４２により図９に示すフローチャートが実行される。
【００７０】
この場合、ステップ９０１で、空間周波数解析部２６は、Ａ／Ｄ変換部２４より入力された画像データから輝度画像ｉ（ｘ，ｙ）を計算する。次に、ステップ９０２で、輝度画像のフーリエ変換を行う。ここで、フーリエ変換の結果の絶対値Ｉ（ｕ，ｖ）は、上述した（１）式により得られる。
【００７１】
次に、ステップ９０３で、（１）式よりＩ（ｕ，０）／Ｉ（０，０）の
０．０５＜（ｕ／Ｎｘ）＜０．２の和、つまり（２）式を求める。
【００７２】
この結果も、実際に求められる傾向からして画像のコントラストとして評価することができる。そして、この結果を、ステップ９０４で、予め設定した閾値Ｌ４と比較する。
【００７３】
この場合も、具体例を上げて説明すると、図６（ａ）、（ｂ）に示す結果から、Ｉ（ｕ，０）／Ｉ（０，０）の０．０５＜（ｕ／Ｎｘ）＜０．２の和、つまり（２）式から、それぞれＬｃ、Ｌｄを求め、これらＬｃ、Ｌｄについて、閾値Ｌ４と比較する。
【００７４】
閾値Ｌ４は、画像のコントラストレベルを２つに区分けするためのもので、この閾値Ｌ４に対してＬｃ、Ｌｄが大きいか小さいかを判断することで、低コントラスト画像、高コントラスト画像を判断できるようにしている。ここでは、閾値Ｌ４は、Ｌｃ＞Ｌ４＞Ｌｄに設定されているものとする。
【００７５】
これにより、図６（ｂ）に示す低コントラスト標本の撮影画像に対応するＬｄの場合、ステップ９０４で、閾値Ｌ４より小さく低コントラスト画像と判断され、ステップ９０５に進む。ステップ９０５では、輪郭強調処理パラメータ設定部４２により輪郭強調処理部４１のゲイン調整部４１２に輪郭強調ゲインＢが設定され、この設定にしたがって信号処理部２５で画像データの処理が行われる。
【００７６】
このようなコントラストが低い画像については、より高い輪郭強調ゲインＢが設定され、コントラストの低さによる画像のシャープ感のなさを補う処理が行われる。
【００７７】
一方、図６（ａ）に示す高コントラスト標本の撮影画像に対応するＬｃの場合、ステップ９０４で、閾値Ｌ４より大きいと判断され、ステップ９０６に進む。ステップ９０６では、輪郭強調処理パラメータ設定部４２により輪郭強調処理部４１のゲイン調整部４１２に輪郭強調ゲインＡが設定され、この設定にしたがって信号処理部２５で画像データの処理が行われる。
【００７８】
このようなコントラストが高い画像については、より低い輪郭強調ゲインＡが設定される。つまり、コントラストの高い画像では、もともと画像の明暗がはっきりしているため、弱めの輪郭強調でも良好な画像が得られる。
【００７９】
従って、このようにすれば、撮像素子２１で撮像した画像データの空間周波数解析の結果に基づいて、画像データのコントラストに応じた輪郭強調処理パラメータ設定部４２による輪郭強調処理部４１の処理パラメータの設定により、画像の状態に最適な輪郭強調処理を行うことができるので、操作者が特別な操作をすることなく、観察標本に最適な輪郭強調処理を行うことができ、常に観察している標本を最適に表現する良好な画像を取得することができる。
【００８０】
なお、上述した実施の形態では、色補正処理、階調補正処理を信号処理部２５で行っているが、これらの色補正処理、階調補正処理は、ＰＣ４４で行うようにしてもよい。また、上述の実施の形態で説明した空間周波数解析の結果と選択した輪郭強調ゲインを、撮像した標本像と共にＰＣ４４の表示部に表示したり、記録部に記録するようにしてもよい。こうすれば、操作者がどのようなパラメータが設定されたか確認することができるので、より一層使い勝手のよい顕微鏡用撮像装置を提供できる。さらに、上述した実施の形態では、輪郭強調ゲインのみを設定したが、空間周波数解析部２６での空間周波数解析の結果に応じて、エッジ抽出部４１１のバンドパスフィルタの帯域を変更するようにしてもよい。
【００８１】
（第３の実施の形態）
次に、本発明の第３の実施の形態について説明する。
【００８２】
図１０は、本発明の第３の実施の形態の概略構成を示すもので、図７と同一部分には、同符号を付している。
【００８３】
この場合、撮像素子２１には、画素ずらし手段５１が設けられている。この画素ずらし手段５１は、顕微鏡１のポート１４から入力される標本像と撮像素子２１の相対位置を変化させるものである。信号処理部２５は、色補正処理部２７と階調補正処理部２８の他に、合成処理手段としての合成処理部５２を有している。合成処理部５２は、画素ずらし手段５１により標本像と撮像素子２１の相対位置を変化させた際に複数の位置で撮像素子２１により撮像された画像データから高解像度の画像データを合成するものである。また、制御部３４は、Ｉ／Ｆ部４３を介してＰＣ４４が接続されるとともに、バス３３を介して空間周波数解析部２６が接続され、この空間周波数解析部２６での空間周波数解析結果に基づいて、画素ずらしの有無を画素ずらし手段５１および合成処理部５２に設定する画素ずらし設定手段３４１を有している。
【００８４】
このような構成において、Ａ／Ｄ変換部２４から空間周波数解析部２６へデジタル変換された画像データが入力されると、信号処理部２５、空間周波数解析部２６および制御部３４により図１１に示すフローチャートが実行される。
【００８５】
この場合、ステップ１１０１で、Ａ／Ｄ変換部２４より入力された画像データから輝度画像ｉ（ｘ，ｙ）を計算する。次に、ステップ１１０２で、輝度画像のフーリエ変換を行う。ここで、フーリエ変換の結果の絶対値Ｉ（ｕ，ｖ）は、上述した（１）式により得られる。
【００８６】
次に、ステップ１１０３で、（１）式よりＩ（ｕ，０）／Ｉ（０，０）の
０．３＜（ｕ／Ｎｘ）＜０．５の和
【数３】

を求める。
【００８７】
この結果は、実際に求められる傾向からして観察倍率などに応じて撮影画像に含まれる高周波成分として評価することができる。そして、この結果を、ステップ１１０４で、で予め設定した閾値Ｌ５と比較する。
【００８８】
この場合も具体例を上げて説明すると、例えば、高周波帯域標本の撮像画像と低周波帯域標本の撮像画像について、それぞれの輝度画像を求め、これら輝度画像のフーリエ変換の結果を図示すると、図１２中の（ａ）、（ｂ）のように表わすことができる。ここで、（ａ）は、高周波帯域標本の場合、（ｂ）は、低周波帯域標本の場合を示している。
【００８９】
そして、これら図１２（ａ）、（ｂ）に示す結果から、Ｉ（ｕ，０）／Ｉ（０，０）の０．３＜（ｕ／Ｎｘ）＜０．５の和、つまり（３）式から、それぞれＬｅ、Ｌｆを求め、これらＬｅ、Ｌｆについて、閾値Ｌ５と比較する。
【００９０】
閾値Ｌ５は、撮影画像に含まれる高周波数成分の量によって周波数帯域を２つに分けるためのもので、この閾値Ｌ５に対してＬｅ、Ｌｆが大きいか小さいかを判断することで、撮影結果の画像に画素ずらしなしでの解像度以下の情報しかふくまれないか、画素ずらしなしでの解像度以上の情報がふくまれるかを判断できるようにしている。ここでは、Ｌｅ＞Ｌ５＜Ｌｆに設定されているものとする。
【００９１】
これにより、図１２（ｂ）に示す低周波帯域標本の撮影画像に対応するＬｆの場合、ステップ１１０４で、閾値Ｌ５より小さく低周波帯域の撮像画像と判断され、ステップ１１０５に進む。ステップ１１０５では、制御部３４の画素ずらし設定手段３４１により、画素ずらし手段５１および合成処理部５２に画素ずらし無しが設定され、この設定に応じて撮像素子２１による標本像の撮影が行われる。
【００９２】
一方、図１２（ａ）に示す高周波帯域標本の撮影画像に対応するＬｅの場合、ステップ１１０４で、閾値Ｌ５より大きく高周波帯域の撮像画像と判断され、ステップ１１０６に進む。ステップ１１０６では、制御部３４の画素ずらし設定手段３４１により、画素ずらし手段５１および合成処理部５２に画素ずらし有りが設定され、この設定にしたがって撮像素子２１による標本像の撮影が行われる。
【００９３】
つまり、ステップ１１０４における判断は、撮影画像に含まれる高周波数成分の量によって異なる判断を下すこととなり、図１２（ｂ）に示す低周波帯域標本の撮影画像のようにＬｆが閾値Ｌ５より小さい場合は、撮影結果の画像に画素ずらし無しでの解像度以下の情報しか含まれないことを判断し、逆に、図１２（ａ）に示す高周波帯域標本の撮影画像のようにＬｅが閾値Ｌ５より大きい場合は、撮影結果の画像に画素ずらし無しで解像度以上の情報が含まれていることを判断する。
【００９４】
そして、撮影画像に画素ずらし無しでの解像度以下の情報しか含まれない場合は、画素ずらしを行って撮影しても画像サイズが大きくなるだけで、空間周波数領域における情報量は変わらないことから、画素ずらし無しが設定され、撮像素子２１での撮像が行われる。また、撮影画像に画素ずらし無しでの解像度以上の情報が含まれる場合は、画素ずらし無しで撮影すると情報が欠落する恐れがあるので、画素ずらし有りが設定され、画素ずらし手段５１により標本像と撮像素子２１の相対位置を変化させた状態で、撮像素子２１による撮像が行われる。
【００９５】
従って、このようにすれば、撮像素子２１で撮像した画像データの空間周波数解析の結果に基づいて、画像データに含まれる高周波成分に応じた画素ずらし手段５１の画素ずらしの有無および合成処理部５２の合成処理の有無の設定により、画像の状態に最適な動作を選択することができるので、操作者が特別な操作をすることなく、観察倍率によらず大きな画像データを記録するためにメモリ容量の不必要な浪費を防止できるとともに、常に観察している標本を最適に表現する良好な画像を取得することができる。
【００９６】
なお、上述した実施の形態では、色補正処理、階調補正処理を信号処理部２５で行っているが、これらの色補正処理、階調補正処理は、ＰＣ４４で行うようにしてもよい。また、上述した実施の形態でで説明した空間周波数解析の結果と選択した画素ずらしの有無を、撮像した標本像と共にＰＣ４４の表示部に表示したり、記録部に記録するようにしてもよい。こうすれば、操作者がどのようなパラメータが設定されたか確認することができるので、より一層使い勝手のよい顕微鏡用撮像装置を提供できる。
【００９７】
その他、本発明は、上記実施の形態に限定されるものでなく、実施段階では、その要旨を変更しない範囲で種々変形することが可能である。
【００９８】
さらに、上記実施の形態には、種々の段階の発明が含まれており、開示されている複数の構成要件における適宜な組み合わせにより種々の発明が抽出できる。例えば、実施の形態に示されている全構成要件から幾つかの構成要件が削除されても、発明が解決しようとする課題の欄で述べた課題を解決でき、発明の効果の欄で述べられている効果が得られる場合には、この構成要件が削除された構成が発明として抽出できる。
【００９９】
なお、上述した実施の形態には、以下の発明も含まれる。
【０１００】
（１）請求項１乃至５のいずれかに記載の顕微鏡用撮像装置であって、前記撮像手段で撮像した画像を表示する表示手段を有し、該表示手段に前記空間周波数解析手段の解析結果と設定結果を表示可能としたことを特徴としている。
【０１０１】
（２）請求項１乃至５のいずれかに記載の顕微鏡用撮像装置であって、前記撮像手段で撮像した画像を記録する記録手段を有し、該記録手段に前記空間周波数解析手段の解析結果と設定結果を記録可能としたことを特徴としている。
【０１０２】
【発明の効果】
以上述べたように本発明によれば、顕微鏡の検鏡法、標本の種類、観察倍率などにかかわらず、常に良好な画像を取得することができる顕微鏡用撮像装置を提供できる。
【図面の簡単な説明】
【図１】本発明の第１の実施の形態の概略構成を示す図。
【図２】第１の実施の形態に用いられる階調特性設定部に記憶される３つの階調特性を示す図。
【図３】第１の実施の形態を説明するためのフローチャート。
【図４】第１の実施の形態の画像データのフーリエ変換の結果を示す図。
【図５】第１の実施の形態の画像データのフーリエ変換の結果を示す図。
【図６】第１の実施の形態の画像データのフーリエ変換の結果を示す図。
【図７】本発明の第２の実施の形態の概略構成を示す図。
【図８】第２の実施の形態に用いられる輪郭強調処理部の概略構成を示す図。
【図９】第２の実施の形態を説明するためのフローチャート。
【図１０】本発明の第３の実施の形態の概略構成を示す図。
【図１１】第３の実施の形態を説明するためのフローチャート。
【図１２】第３の実施の形態の画像データのフーリエ変換の結果を示す図。
【図１３】従来の顕微鏡用撮像装置の一例の概略構成を示す図。
【図１４】従来の顕微鏡用撮像装置の他例の概略構成を示す図。
【図１５】従来の顕微鏡用撮像装置の他例の概略構成を示す図。
【符号の説明】
１…顕微鏡
２…撮像装置本体
３…透過照明用光源
３ａ…光路
４…落射照明用光源
４ａ…光路
５…コレクタレンズ
６…ミラー
７…窓レンズ
８…ＦＳ（視野絞り）
９…ＡＳ（開口絞り）
１０…コンデンサレンズ
１１…標本
１２…対物レンズ
１３…結像レンズ
１４…ポート
１５…キューブユニット
２１…撮像素子
２２…撮像素子駆動部
２３…前置処理部
２４…Ａ／Ｄ変換部
２５…信号処理部
２６…空間周波数解析部
２７…色補正処理部
２８…階調補正処理部
２９…色補正パラメータ設定部
３０…階調特性設定部
３１…Ｄ／Ａ変換器
３２…表示部
３３…バス
３４…制御部
３４１…画素ずらし設定手段
３５…記録部
３６…操作部
４１…輪郭強調処理部
４１１…エッジ抽出部
４１２…ゲイン調整部
４１３…輪郭強調部
４２…輪郭強調処理パラメータ設定部
４３…Ｉ／Ｆ部
４４…ＰＣ
５１…画素ずらし手段
５２…合成処理部[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an imaging apparatus for a microscope that captures and records a specimen observation image by a microscope with an imaging element such as a CCD.
[0002]
[Prior art]
Conventionally, as an example of an imaging device for a microscope, as shown in FIG. 13, an imaging device body 200 such as a digital camera for a microscope is connected to a port 101 of a microscope 100, and a specimen image output from the port 101 is captured. There are some which are made to pick up images.
[0003]
In this case, in the microscope 100, the light emitted from the light source 102 is converted into parallel light through the collector lens 103, reflected by the mirror 104, the window lens 105, the FS (field stop) 106, the AS (aperture stop) 107, The specimen 109 is irradiated via the condenser lens 108, and transmitted light from the specimen 109 is output from the port 101 as a specimen image via the objective lens 110 and the imaging lens 111. On the other hand, the imaging apparatus main body 200 is provided with an imaging element 201 such as a CCD that captures a specimen image output from the port 101 of the microscope 100. The image sensor 201 is driven with an exposure time based on a drive signal from the image sensor drive unit 202 and inputs an output signal to the pre-processing unit 203. The pre-processing unit 203 converts the output signal of the image sensor 201 into a video signal by the control pulse given from the image sensor drive unit 202 and inputs it to the A / D converter 204. The A / D conversion unit 204 outputs the video signal from the preprocessing unit 203 as digital image data based on the clock signal from the image sensor driving unit 202. The image data output from the A / D conversion unit 204 is input to the signal processing unit 205. The signal processing unit 205 performs signal processing such as color correction and gradation correction on the image data. The output from the signal processing unit 205 is converted into an analog signal by the D / A conversion unit 206 and displayed on the display unit 207 as a moving image. Further, after waiting for an instruction from the operation unit 208, the control unit 209 sends the image data from the signal processing unit 205 to the recording unit 211 via the bus 210 and records it as a still image.
[0004]
As another example of such a microscope imaging apparatus, there is one configured as shown in FIG. In FIG. 14, the same parts as those in FIG. 13 are denoted by the same reference numerals. In this case, in the imaging apparatus main body 200, the D / A conversion unit 206, the display unit 207, and the recording unit 211 are deleted. Instead, the I / F unit 212 is connected to the control unit 209. A personal computer (personal computer) 300 is connected to the I / F unit 212, and operations, image data display, and recording are performed by the personal computer 300. In this type, part of the image processing may be performed by the personal computer 300.
[0005]
Further, as another example of such an imaging apparatus for a microscope, there is an apparatus configured as shown in FIG. In FIG. 15, the same parts as those in FIG. 13 are denoted by the same reference numerals. In this case, in the imaging apparatus main body 200, an image shifting unit 213 is provided in the imaging element 201. The image shifting means 213 captures a plurality of images by shifting the relative position of the sample image output from the port 101 of the microscope 100 and the image sensor 201. These images are combined to obtain a higher resolution image. Some of them adopt a so-called pixel shift method that can obtain the above.
[0006]
The imaging apparatus main body 200 is connected to the port 101 of the microscope 100 and is used to capture and record an image such as a stained specimen output from the port 101.
[0007]
However, these microscope imaging apparatuses optimally perform image adjustment by signal processing such as color correction and gradation correction in the signal processing unit 205 with respect to the type of specimen on the microscope 100 side, the microscopy method, and the observation magnification. I will not. For this reason, there has been a problem that if the type of specimen, the spectroscopic method, the observation magnification, and the like are changed, an image having a satisfactory expression cannot be obtained.
[0008]
In such a case, the user uses the image processing software of the personal computer, captures the image data acquired by the digital camera for the microscope, adjusts the gradation characteristics, brightness, hue, saturation of the image, and edge enhancement processing, etc. There was a problem that it was forced to do troublesome work.
[0009]
Therefore, as a method for solving such a problem, as disclosed in Japanese Patent Laid-Open No. 2001-75013, the state of the microscopic method in the microscope is detected, and the color of the observation image is determined based on the detected microscopic method. In addition, it is possible to determine the degree of the color balance, determine the area where color balance is performed, and perform color balance adjustment according to the color balance adjustment amount set for the determined area.
[0010]
According to such a method, even when using a microscope in which various spectroscopic methods such as transmitted bright field observation and fluorescence observation can be switched, it is possible to respond to any spectroscopic method without putting extra labor on the operator. Optimal gradation adjustment can be performed.
[0011]
On the other hand, the microscope digital camera employing the pixel shifting method described in FIG. 11 has a very wide variation range of the observation magnification unlike a general digital camera, and accordingly, the resolution of the observation image changes greatly. Therefore, the resolution obtained by the pixel shifting method may be larger than the optical resolution of the microscope optical system (objective lens). In such a case, an image that is higher than the optical resolution of the microscope optical system is obtained even if pixel shifting is performed. On the contrary, the memory capacity is wasted in order to record large image data.
[0012]
In order to solve this problem, as disclosed in Japanese Patent Application Laid-Open No. 2001-86384, the optical resolution of the microscope optical system is compared with the resolution of the image sensor on the camera side. It is considered that the high-resolution shooting mode is switched.
[0013]
According to such a method, imaging can be performed with the optical resolution of the imaging device that matches the optical resolution of the microscope optical system, so that unnecessary waste of memory capacity for recording image data can be prevented.
[0014]
[Problems to be solved by the invention]
However, in the method disclosed in Japanese Patent Laid-Open No. 2001-75013, the observation image is adjusted only based on the microscopic method. For example, even if the same microscopic method is used, the types of specimens are different. Even in this case, it is difficult to optimize the adjustment of the observation image. In addition, in the method disclosed in Japanese Patent Laid-Open No. 2001-86384, it is possible to photograph in a photographing mode that matches the optical resolution of the microscope optical system. For example, when the optical resolution of the microscope optical system is high, However, if the spatial frequency of the sample structure itself is low, high-resolution shooting may occur even though the shot image is below the resolution of the high-resolution shooting mode. Still, there is a problem that memory capacity is wasted.
[0015]
The present invention has been made in view of the above circumstances, and an object thereof is to provide an imaging apparatus for a microscope that can always obtain a good image regardless of the microscopy method, the type of specimen, the observation magnification, and the like. And
[0016]
[Means for Solving the Problems]
According to the first aspect of the present invention, an imaging unit that captures a specimen image obtained from a microscope, a color correction unit that performs color correction processing on the image data of the specimen image captured by the imaging unit, and gradation correction processing A luminance image is obtained from signal processing means having gradation correction means and image data picked up by the image pickup means, and a first feature amount of a photographed image represented by a DC component as a result of Fourier transform of the luminance image is obtained. In addition, a second feature amount of the photographed image represented by an integral value of a preset frequency range as a result of the Fourier transform of the luminance image is obtained, and the first and second feature amounts of the photographed image and the first and second features are obtained. A spatial frequency analyzing means for outputting a result obtained by comparing each of the second feature amounts with a preset threshold value; a gradation characteristic setting means for setting a gradation characteristic of the gradation correction means; Color correction parameter setting means for setting a color correction parameter of the color correction means, and based on the analysis result by the spatial frequency analysis means, the gradation characteristics of the gradation correction means by the gradation characteristic setting means And at least one of setting the color correction parameter of the color correction unit by the color correction parameter setting unit is enabled. It is a feature.
[0019]
Claim 2 The invention described is an imaging unit that captures a sample image obtained from a microscope, a color correction unit that performs color correction processing on image data of the sample image captured by the imaging unit, a gradation correction unit that performs gradation correction processing, and Signal processing means having edge enhancement processing means for edge enhancement processing; A luminance image is obtained from image data picked up by the imaging means, and a feature value of the photographed image represented by an integral value of a preset frequency range of a result of Fourier transform of the luminance image is obtained, and a feature amount of the photographed image is obtained. And a spatial frequency analyzing means for outputting a result of comparing a preset threshold value, And a contour emphasis processing parameter setting means for setting processing parameters of the contour emphasis processing means based on an analysis result by the spatial frequency analysis means.
[0021]
Claim 3 The described invention includes an imaging unit that captures a specimen image obtained from a microscope, a pixel shift unit that changes a relative position between the sample image and the imaging unit, and a relative relationship between the sample image and the imaging unit by the pixel shift unit. An image processing unit having a synthesis processing unit that synthesizes image data captured by the imaging unit at a plurality of positions when the position is changed, and a spatial frequency for performing a spatial frequency analysis of the image data captured by the imaging unit It comprises analysis means, and pixel shift setting means for setting the presence / absence of pixel shift by the pixel shift means and the presence / absence of synthesis processing by the synthesis processing means based on the analysis result by the spatial frequency analysis means. .
[0022]
Claim 4 The described invention is claimed. 3 In the described invention, the spatial frequency analysis unit obtains a luminance image from the image data imaged by the imaging unit, and a captured image represented by an integral value of a preset frequency range as a result of Fourier transform of the luminance image. The feature amount of
Based on the result of comparing the feature amount of the photographed image with a preset threshold value, the pixel shift setting unit can set whether or not the pixel shift unit is shifted and whether or not the combining process is performed. It is characterized by that.
[0023]
As a result, according to the present invention, by performing various corrections, image processing, and shooting mode settings based on the result of spatial frequency analysis of the image, it is optimal for an image shot regardless of the specimen or the spectroscopic method. Various processes can be performed.
[0024]
In particular,
Based on the result of the spatial frequency analysis of the image data picked up by the image pickup means, the microscopic examination method can be determined, and the gradation characteristics and color correction processing means in the gradation correction processing means according to the contrast of the image data By setting the color correction parameters in, it is possible to perform gradation correction processing and color correction processing that are optimal for the image state, so that even when applied to a microscope that can switch various spectroscopic methods, the operator However, it is possible to always perform the gradation correction process and the color correction process optimal for the observation specimen without performing any special operation.
[0025]
Further, based on the result of the spatial frequency analysis of the image data picked up by the image pickup means, by setting the processing parameters of the contour emphasis processing means by the contour emphasis processing parameter setting means according to the contrast of the image data, it is optimal for the image state. Since the contour enhancement process can be performed, it is possible to always perform the optimum contour enhancement process for the observation specimen without any special operation by the operator.
[0026]
Further, based on the result of the spatial frequency analysis of the image data captured by the image capturing means, setting of the pixel shifting presence / absence of the pixel shifting means and the presence / absence of the combining processing of the combining processing means according to the high frequency component included in the image data Can select the most suitable operation for the image state, so that the operator does not need to perform a special operation and records large image data regardless of the observation magnification, thus preventing unnecessary waste of memory capacity. it can.
[0027]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0028]
(First embodiment)
FIG. 1 shows a schematic configuration of a microscope imaging apparatus to which the present invention is applied. The imaging device for a microscope includes a microscope 1 that can switch various spectroscopic methods such as bright field observation, phase difference observation, differential interference observation, polarization observation, dark field observation, and fluorescence observation, and a sample obtained from the microscope 1. An image pickup apparatus main body 2 that picks up an image is included.
[0029]
The microscope 1 is provided with a transmission illumination light source 3 and an epi-illumination light source 4.
[0030]
Then, the light emitted from the light source 3 for transmitted illumination is converted into parallel light through the collector lens 5 and reflected by the mirror 6, the window lens 7, the FS (field stop) 8, the AS (aperture stop) 9, and the condenser lens. The specimen 11 is irradiated via 10, and the transmitted light from the specimen 11 is output from the port 14 as a specimen image via the objective lens 12 and the imaging lens 13. On the other hand, the light emitted from the epi-illumination light source 4 is irradiated onto the specimen 11 via the objective lens 12, and the reflected light from the specimen 11 is output from the port 14 via the objective lens 12 and the imaging lens 13. Is done.
[0031]
In the optical path 3a of the transmitted illumination light from the light source 3 for transmitted illumination, the optical path 4a of the incident illumination light from the incident illumination light source 4, and the observation optical path S in which these optical paths overlap, the cube unit 15 and various filters (not shown), An optical element such as a polarizing element is detachably provided. In this case, switching of the cube unit 15 and various optical elements in accordance with switching instructions of various spectroscopic methods such as bright field observation, phase difference observation, differential interference observation, polarization observation, dark field observation, and fluorescence observation with the microscope 1 The objective lens 12 on the observation optical path S can be switched by an instruction to change the observation magnification.
[0032]
On the other hand, the imaging device main body 2 is connected to the port 14 of the microscope 1. In the imaging apparatus main body 2, an imaging element 21 such as a CCD is arranged as an imaging means at a position where a specimen image is projected on the observation optical path S from the microscope 1. The image pickup device 21 is driven with an exposure time based on a drive signal from the image pickup device drive unit 22, picks up a sample image input from the port 14 of the microscope 1, and performs photoelectric conversion.
[0033]
A pre-processing unit 23 is connected to the image sensor 21. The pre-processing unit 23 converts the electrical signal from the image sensor 21 into a video signal by a control pulse given from the image sensor driver 22 and separates it into R (red), G (green), and B (blue) color signals. .
[0034]
An A / D conversion unit 24 is connected to the front processing unit 23. The A / D conversion unit 24 converts the video signal from the pre-processing unit 23 into digital image data based on the clock signal from the image sensor driving unit 22 and outputs the digital image data.
[0035]
The A / D converter 24 is connected to a signal processor 25 as a signal processor and a spatial frequency analyzer 26 as a spatial frequency analyzer. The signal processing unit 25 includes a color correction processing unit 27 as a color correction processing unit that performs color correction processing using a color conversion matrix, and a gradation correction processing unit 28 as a gradation correction processing unit that performs gradation correction processing. Signal processing such as color correction and gradation correction is performed on the image data input from the A / D converter 24. The spatial frequency analysis unit 26 performs spatial frequency analysis on the image data input from the A / D conversion unit 24. The spatial frequency analysis in the spatial frequency analysis unit 26 will be described in detail with reference to FIG.
[0036]
The spatial frequency analysis unit 26 is connected to a color correction parameter setting unit 29 as a color correction parameter setting unit and a gradation characteristic setting unit 30 as a gradation characteristic setting unit. The gradation characteristic setting unit 30 stores three gradation characteristic parameters (gradation characteristic A, gradation characteristic B, and gradation characteristic C) as shown in FIGS. 2 (a), (b), and (c). Based on the analysis result of the spatial frequency analysis unit 26, the corresponding gradation characteristic parameter is set in the gradation correction processing unit 28 of the signal processing unit 25. Further, the color correction parameter setting unit 29 includes three color conversion matrices (color conversion matrix A, color conversion matrix) as color correction parameters respectively corresponding to the above-described gradation characteristics A, gradation characteristics B, and gradation characteristics C. B, a color conversion matrix C) are stored, and the color conversion matrix corresponding to the color of the signal processing unit 25 is determined based on the analysis result of the spatial frequency analysis unit 26, as in the case of the gradation characteristic setting unit 30. The correction processing unit 27 is set.
[0037]
A display unit 32 is connected to the signal processing unit 25 via a D / A converter 31. The D / A converter 31 converts the output from the signal processing unit 25 into an analog signal, and displays a moving image on the display unit 32.
[0038]
A control unit 34 and a recording unit 35 are connected to the signal processing unit 25 via a bus 33. The control unit 34 records the image data from the signal processing unit 25 as a still image in the recording unit 35 via the bus 33 in accordance with an instruction from the operation unit 36.
[0039]
In such a configuration, when transmissive illumination light is emitted from the transmissive illumination light source 3, this light is converted into parallel light through the collector lens 5, reflected by the mirror 6, the window lens 7, FS (field stop). ) 8, the sample 11 is irradiated through the AS (aperture stop) 9 and the condenser lens 10. The transmitted light from the sample 11 is output from the port 14 as a sample image via the objective lens 12 and the imaging lens 13 and is imaged by the microscope 1.
[0040]
The image sensor 21 photoelectrically converts the captured sample image and outputs the electrical signal to the pre-processing unit 23. The pre-processing unit 23 converts the electrical signal from the image sensor 21 into a video signal and separates it into R (red), G (green), and B (blue) color signals.
[0041]
The video signal separated into each color signal from the pre-processing unit 23 is converted into digital image data by the A / D conversion unit 24 and input to the signal processing unit 25 and the spatial frequency analysis unit 26.
[0042]
Here, the flowchart shown in FIG. 3 is executed by the signal processing unit 25, the spatial frequency analysis unit 26, the color correction parameter setting unit 29, and the gradation characteristic setting unit 30.
[0043]
First, in step 301, a luminance image i (x, y) is calculated from the image data input from the A / D conversion unit 24. Next, in step 302, the luminance image is subjected to Fourier transform.
[0044]
Here, if the absolute value of the result of Fourier transform of the luminance image is I (u, v),
[Expression 1]

Is obtained. Where x is the horizontal position of the image, y is the vertical position of the image, Nx is the number of pixels in the horizontal direction of the image, Ny is the number of pixels in the vertical direction of the image, u is the spatial frequency in the horizontal direction, and v is The spatial frequency in the vertical direction, j is an imaginary number.
[0045]
Next, in step 303, the brightness of the image is obtained from I (0, 0), that is, a direct current component, from the equation (1), and compared with a preset threshold value L1.
[0046]
In this case, a specific example will be described. For example, a captured image of a bright sample such as bright field observation (or phase difference observation) and a captured image of a dark sample such as fluorescence observation (or dark field observation), respectively. When luminance images are obtained for and the results of Fourier transformation of these luminance images are illustrated, they can be represented as (a) and (b) in FIG. Here, (a) shows the case of bright field observation (or phase difference observation), and (b) shows the case of fluorescence observation (or dark field observation). In addition, the horizontal axis of the figure shows the frequency, where the sampling frequency is 1 and the Nyquist frequency is 0.5. 5 shows only a part of FIG. 4 in an enlarged manner.
[0047]
Then, from the results shown in (a) and (b) of FIG. 4 (FIG. 5), I (0, 0), that is, La and Lb are obtained as the brightness of the image from the direct current component, and for these La and Lb, Compare with threshold L1.
[0048]
In this case, the threshold value L1 serves as a criterion for determining a captured image of a bright sample and a captured image of a dark sample, and is set between La and Lb. Thus, by determining whether La and Lb are larger or smaller than the threshold value L1, it is a photographed image for bright field observation (or phase difference observation) or a photographed image for fluorescence observation (or dark field observation). It becomes possible to judge whether it exists.
[0049]
Here, if I (0,0) is smaller than L1, for example, in the case of Lb shown in FIG. 4 (FIG. 5), it is determined that the image is a dark captured image by fluorescence observation (or dark field observation), and the process proceeds to step 304. . In step 304, the tone characteristic setting unit 30 sets the tone characteristic B as shown in FIG. 2B in the tone correction processing unit 28 as the tone characteristic parameter, and at the same time, the color correction parameter setting unit 29 sets the tone characteristic B. A color conversion matrix B optimum for the gradation characteristic B is set in the color correction processing unit 27. Then, the image data is processed by the signal processing unit 25 according to these settings.
[0050]
In this case, the captured image by fluorescence observation (or dark field observation) has a luminance distribution distributed from a dark part to a bright part, and by using a gradation characteristic B as shown in FIG. The luminance distribution can be expressed on average.
[0051]
On the other hand, if I (0,0) is larger than L1 in step 303, for example, in the case of La shown in FIG. 4 (FIG. 5), it is determined that the captured image is bright by bright field observation (or phase difference observation). Proceed to step 305.
[0052]
In step 305, I (u, 0) / I (0,0)
Sum of 0.05 <(u / Nx) <0.2
[Expression 2]

Ask for.
[0053]
This result can be evaluated as the contrast of the image based on the tendency actually required. Then, the result is compared with threshold values L2 and L3 set in advance in steps 306 and 307.
[0054]
In this case as well, a specific example will be described. For example, luminance images are obtained for a captured image of a high-contrast sample and a captured image of a low-contrast sample, and the result of Fourier transform of these luminance images is illustrated in FIG. (A) and (b). Here, (a) shows the case of a high contrast sample, and (b) shows the case of a low contrast sample. From the results shown in FIGS. 6A and 6B, I (u, 0) / I (0,0)
Lc and Ld are obtained from the sum of 0.05 <(u / Nx) <0.2, that is, from equation (2), and these Lc and Ld are compared with threshold values L2 and L3.
[0055]
The threshold value L2 is a value for determining a lower contrast image as a low contrast image, and the threshold value L3 is a value for determining a higher value as a high contrast image. Lc and Ld are larger or smaller than these threshold values L2 and L3. By determining whether or not, a low-contrast image, a high-contrast image, and intermediate images thereof can be determined in three stages. Here, it is assumed that the threshold L2 is set to Lc>L2> Ld, and the threshold L3 is set to Lc> L3.
[0056]
Thereby, in the case of Ld corresponding to the captured image of the low-contrast sample shown in FIG. 6B, it is determined in step 306 that the image is smaller than the threshold value L2, and the process proceeds to step 308. In step 308, the tone characteristic setting unit 30 sets the tone characteristic C as shown in FIG. 2C as the tone characteristic parameter in the tone correction processing unit 28, and at the same time, the color correction parameter setting unit 29 sets the tone characteristic C. A color conversion matrix A optimum for the gradation characteristic C is set in the color correction processing unit 27. Then, the image data is processed by the signal processing unit 25 according to these settings.
[0057]
In this case, since an image with low contrast is considered to be concentrated in a place where the luminance distribution of the image is bright, a gradation characteristic C as shown in FIG. 2C and a color corresponding to the gradation characteristic C are displayed. By selecting the conversion matrix C, the contrast can be increased and the image can be expressed.
[0058]
In the case of Lc corresponding to the captured image of the high contrast sample shown in FIG. 6A, it is determined in step 306 that it is larger than the threshold value L2, and the process proceeds to step 307. In step 307, it is determined that the image is higher in contrast than the threshold value L3, and the process proceeds to step 309. In step 309, the gradation characteristic setting unit 30 sets the gradation characteristic A as shown in FIG. 2A as the gradation characteristic parameter in the gradation correction processing unit 28, and at the same time, the color correction parameter setting unit 29 A color conversion matrix A optimal for the gradation characteristic A is set in the color correction processing unit 27. Then, the image data is processed by the signal processing unit 25 according to these settings.
[0059]
In this case, an image with a high contrast is considered to have a bright part through which only illumination light without a specimen is transmitted and a dark part with a specimen distributed in bright field observation. By selecting such a gradation characteristic A and a color conversion matrix A corresponding to the gradation characteristic A, the contrast of a relatively dark specimen portion which is a noticeable portion on the image can be expanded and a bright illumination portion can be expressed. It becomes like this.
[0060]
Further, although not given as a specific example, for example, in the case of a captured image having a contrast located in the middle of the captured images shown in FIGS. 6A and 6B, it is determined in step 306 that it is larger than the threshold value L2. In step 307, it is determined that the image is smaller than the threshold value L3 and is an intermediate contrast image, and the process proceeds to step 310. In step 310, the tone characteristic setting unit 30 sets the tone characteristic B as shown in FIG. 2B in the tone correction processing unit 28 as the tone characteristic parameter, and at the same time, the color correction parameter setting unit 29 sets the tone characteristic B. A color conversion matrix B optimum for the gradation characteristic B is set in the color correction processing unit 27. Then, the image data is processed by the signal processing unit 25 according to these settings.
[0061]
In this case, since it is considered that the luminance distribution of the image having an intermediate contrast is uniformly spread, the gradation characteristic B as shown in FIG. 2B and the color corresponding to the gradation characteristic B are displayed. By selecting the conversion matrix B, the observation image can be expressed well.
[0062]
Accordingly, in this way, the spectroscopic method in the microscope 1 can be determined based on the result of the spatial frequency analysis of the image data captured by the image sensor 21, and the gradation correction processing unit corresponding to the contrast of the image data By setting the tone characteristics at 28 and setting the color correction parameters at the color correction processing unit 27, it is possible to perform tone correction processing and color correction processing that are optimal for the state of the image. Even when applied to a microscope that can switch between various spectroscopic methods, the operator can perform optimum tone correction processing and color correction processing on the observation specimen without any special operation, and always observe It is possible to obtain a good image that optimally represents the sample that is present.
[0063]
Note that the result of the spatial frequency analysis described in the above-described embodiment, the selected gradation characteristics, and the color conversion matrix may be displayed on the display unit 32 or recorded in the recording unit 35 together with the captured sample image. Good. By doing so, the operator can confirm what parameters have been set, so that it is possible to provide a microscope imaging apparatus that is even easier to use.
[0064]
(Second Embodiment)
Next, a second embodiment of the present invention will be described.
[0065]
FIG. 7 shows a schematic configuration of the second embodiment of the present invention, and the same parts as those in FIG.
[0066]
In this case, a signal processing unit 25 and a spatial frequency analysis unit 26 are connected to the A / D conversion unit 24. In addition to the color correction processing unit 27 and the gradation correction processing unit 28, the signal processing unit 25 has an edge enhancement processing unit 41 as an edge enhancement processing unit. As shown in FIG. 8, the contour enhancement processing unit 41 includes an edge extraction unit 411, a gain adjustment unit 412, and a contour enhancement unit 413. In this case, the image data input from the A / D conversion unit 24 to the contour emphasis processing unit 41 is subjected to a band pass filter by the edge extraction unit 411 to extract edges. The extracted edge component is gained by the gain adjusting unit 412, added to the image data input from the gradation correction processing unit 28 by the contour emphasizing unit 413, and sent to the control unit 34 via the bus 33. It is.
[0067]
The spatial frequency analysis unit 26 is connected to a contour enhancement processing parameter setting unit 42 as a contour enhancement processing parameter setting unit. The contour emphasis processing parameter setting unit 42 stores a lower contour emphasis gain A and a higher contour emphasis gain B as processing parameters, and the contour emphasis processing unit 41 is based on the analysis result of the spatial frequency analysis unit 26. The contour emphasis gain A or the contour emphasis gain B is set for the gain adjustment unit 412.
[0068]
A personal computer (hereinafter abbreviated as PC) 44 is connected to the control unit 34 via an I / F unit 43. The PC 44 has the functions of the display unit 32, the recording unit 35, and the operation unit 36 described in FIG.
[0069]
In such a configuration, when digitally converted image data is input from the A / D conversion unit 24 to the spatial frequency analysis unit 26, the signal processing unit 25, the spatial frequency analysis unit 26, and the contour enhancement processing parameter setting unit 42 The flowchart shown in FIG. 9 is executed.
[0070]
In this case, in step 901, the spatial frequency analysis unit 26 calculates a luminance image i (x, y) from the image data input from the A / D conversion unit 24. Next, in step 902, Fourier transformation of the luminance image is performed. Here, the absolute value I (u, v) as a result of the Fourier transform is obtained by the above-described equation (1).
[0071]
Next, in step 903, I (u, 0) / I (0,0)
Sum of 0.05 <(u / Nx) <0.2, that is, formula (2) is obtained.
[0072]
This result can also be evaluated as the contrast of the image from the tendency actually required. Then, in step 904, this result is compared with a preset threshold value L4.
[0073]
In this case as well, a specific example will be described. From the results shown in FIGS. 6A and 6B, 0.05 <(u / Nx) <I (u, 0) / I (0,0). Lc and Ld are respectively obtained from the sum of 0.2, that is, the expression (2), and these Lc and Ld are compared with the threshold value L4.
[0074]
The threshold value L4 is used to divide the contrast level of the image into two, and by determining whether Lc and Ld are larger or smaller than the threshold value L4, a low-contrast image and a high-contrast image can be determined. I have to. Here, it is assumed that the threshold L4 is set to Lc>L4> Ld.
[0075]
As a result, in the case of Ld corresponding to the captured image of the low-contrast sample shown in FIG. 6B, it is determined in step 904 that the image is smaller than the threshold value L4 and the process proceeds to step 905. In step 905, the contour emphasis processing parameter setting unit 42 sets the contour emphasis gain B in the gain adjustment unit 412 of the contour emphasis processing unit 41, and the signal processing unit 25 processes the image data according to this setting.
[0076]
For an image with such a low contrast, a higher contour emphasis gain B is set, and processing is performed to compensate for the lack of sharpness of the image due to the low contrast.
[0077]
On the other hand, in the case of Lc corresponding to the captured image of the high contrast sample shown in FIG. 6A, it is determined in step 904 that it is larger than the threshold value L4, and the process proceeds to step 906. In step 906, the contour emphasis processing parameter setting unit 42 sets the contour emphasis gain A in the gain adjustment unit 412 of the contour emphasis processing unit 41, and the signal processing unit 25 processes the image data according to this setting.
[0078]
For such an image having a high contrast, a lower edge enhancement gain A is set. That is, in an image with high contrast, the image is originally bright and dark, so that a good image can be obtained even with weaker edge enhancement.
[0079]
Therefore, in this way, based on the result of the spatial frequency analysis of the image data captured by the image sensor 21, the processing parameters of the contour enhancement processing unit 41 by the contour enhancement processing parameter setting unit 42 according to the contrast of the image data are set. By setting, it is possible to perform contour enhancement processing that is optimal for the state of the image, so that the operator can perform contour enhancement processing that is optimal for observation specimens without any special operation, and the specimen that is always observed It is possible to obtain a good image that optimally expresses.
[0080]
In the above-described embodiment, the color correction process and the gradation correction process are performed by the signal processing unit 25. However, the color correction process and the gradation correction process may be performed by the PC 44. Further, the result of the spatial frequency analysis described in the above embodiment and the selected contour emphasis gain may be displayed on the display unit of the PC 44 or recorded in the recording unit together with the captured sample image. By doing so, the operator can confirm what parameters have been set, so that it is possible to provide a microscope imaging apparatus that is even easier to use. Furthermore, in the embodiment described above, only the edge enhancement gain is set, but the band of the bandpass filter of the edge extraction unit 411 is changed according to the result of the spatial frequency analysis in the spatial frequency analysis unit 26. Also good.
[0081]
(Third embodiment)
Next, a third embodiment of the present invention will be described.
[0082]
FIG. 10 shows a schematic configuration of the third embodiment of the present invention, and the same parts as those in FIG.
[0083]
In this case, the image sensor 21 is provided with pixel shifting means 51. This pixel shifting means 51 is for changing the relative position between the sample image input from the port 14 of the microscope 1 and the image sensor 21. In addition to the color correction processing unit 27 and the gradation correction processing unit 28, the signal processing unit 25 has a synthesis processing unit 52 as a synthesis processing unit. The composition processing unit 52 synthesizes high-resolution image data from image data captured by the image sensor 21 at a plurality of positions when the relative position between the sample image and the image sensor 21 is changed by the pixel shifting unit 51. is there. In addition, the control unit 34 is connected to the PC 44 via the I / F unit 43 and to the spatial frequency analysis unit 26 via the bus 33, and based on the spatial frequency analysis result in the spatial frequency analysis unit 26. The pixel shift setting means 341 for setting the presence / absence of pixel shift in the pixel shift means 51 and the composition processing unit 52 is provided.
[0084]
In such a configuration, when image data that has been digitally converted is input from the A / D conversion unit 24 to the spatial frequency analysis unit 26, the signal processing unit 25, the spatial frequency analysis unit 26, and the control unit 34, as shown in FIG. A flowchart is executed.
[0085]
In this case, in step 1101, a luminance image i (x, y) is calculated from the image data input from the A / D conversion unit 24. Next, in step 1102, Fourier transformation of the luminance image is performed. Here, the absolute value I (u, v) as a result of the Fourier transform is obtained by the above-described equation (1).
[0086]
Next, in step 1103, I (u, 0) / I (0,0)
Sum of 0.3 <(u / Nx) <0.5
[Equation 3]

Ask for.
[0087]
This result can be evaluated as a high-frequency component included in the photographed image according to the observation magnification or the like based on the tendency actually required. Then, in step 1104, this result is compared with the threshold value L5 set in advance.
[0088]
In this case as well, a specific example will be described. For example, luminance images are obtained for a captured image of a high-frequency band sample and a captured image of a low-frequency band sample, and the result of Fourier transform of these luminance images is illustrated in FIG. It can be expressed as (a) and (b). Here, (a) shows the case of a high frequency band sample, and (b) shows the case of a low frequency band sample.
[0089]
Then, from the results shown in FIGS. 12A and 12B, the sum of 0.3 <(u / Nx) <0.5 of I (u, 0) / I (0,0), that is, (3 ) Respectively, Le and Lf are obtained, and these Le and Lf are compared with a threshold value L5.
[0090]
The threshold value L5 is used to divide the frequency band into two according to the amount of the high frequency component included in the captured image. By determining whether Le and Lf are larger or smaller than this threshold value L5, It is possible to determine whether the image contains only information below the resolution without pixel shifting or whether the information above the resolution without pixel shifting is included. Here, it is assumed that Le> L5 <Lf.
[0091]
As a result, in the case of Lf corresponding to the captured image of the low frequency band sample shown in FIG. 12B, it is determined in step 1104 that the captured image has a low frequency band smaller than the threshold L5, and the process proceeds to step 1105. In step 1105, the pixel shift setting unit 341 of the control unit 34 sets no pixel shift to the pixel shift unit 51 and the composition processing unit 52, and the sample image is taken by the image sensor 21 according to this setting.
[0092]
On the other hand, in the case of Le corresponding to the captured image of the high-frequency band sample shown in FIG. 12A, it is determined in step 1104 that the image is a captured image in the high-frequency band that is larger than the threshold value L5. In step 1106, the pixel shift setting means 341 of the control unit 34 sets pixel shift presence / absence in the pixel shift means 51 and the composition processing unit 52, and the sample image is taken by the image sensor 21 according to this setting.
[0093]
That is, the determination in step 1104 is different depending on the amount of the high frequency component included in the captured image, and when Lf is smaller than the threshold L5 as in the captured image of the low frequency band sample shown in FIG. Determines that the captured image contains only information below the resolution without pixel shift, and conversely, Le is larger than the threshold value L5 as in the captured image of the high-frequency band sample shown in FIG. In this case, it is determined that the information of the resolution or higher is included in the captured image without shifting pixels.
[0094]
And if the captured image contains only information below the resolution without pixel shifting, the amount of information in the spatial frequency domain does not change, only the image size increases even when shooting with pixel shifting, No pixel shift is set, and imaging with the image sensor 21 is performed. In addition, when the captured image includes information more than the resolution without pixel shifting, information may be lost if the image is captured without pixel shifting, so that pixel shifting is set, and the pixel shifting means 51 sets the sample image. Imaging with the imaging element 21 is performed in a state where the relative position of the imaging element 21 is changed.
[0095]
Therefore, in this case, based on the result of the spatial frequency analysis of the image data captured by the image sensor 21, whether or not the pixel shift of the pixel shift unit 51 according to the high frequency component included in the image data and the synthesis processing unit 52 are performed. Depending on the setting of whether or not to synthesize, it is possible to select the optimal operation for the state of the image, so that the operator has no memory capacity to record large image data regardless of the observation magnification without performing special operations. Therefore, it is possible to obtain a good image that optimally represents the specimen that is always observed.
[0096]
In the above-described embodiment, the color correction process and the gradation correction process are performed by the signal processing unit 25. However, the color correction process and the gradation correction process may be performed by the PC 44. Further, the result of the spatial frequency analysis described in the above embodiment and the presence / absence of the selected pixel shift may be displayed on the display unit of the PC 44 or recorded in the recording unit together with the captured sample image. In this way, since the operator can confirm what parameters are set, it is possible to provide a microscope imaging apparatus that is even easier to use.
[0097]
In addition, this invention is not limited to the said embodiment, In the implementation stage, it can change variously in the range which does not change the summary.
[0098]
Furthermore, the above embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements. For example, even if some constituent requirements are deleted from all the constituent requirements shown in the embodiment, the problem described in the column of the problem to be solved by the invention can be solved, and is described in the column of the effect of the invention. If the above effect is obtained, a configuration from which this configuration requirement is deleted can be extracted as an invention.
[0099]
In addition, the following invention is also contained in embodiment mentioned above.
[0100]
(1) The microscope imaging apparatus according to any one of claims 1 to 5, further comprising display means for displaying an image picked up by the image pickup means, and an analysis result of the spatial frequency analysis means on the display means The setting result can be displayed.
[0101]
(2) The microscope imaging apparatus according to any one of claims 1 to 5, further comprising a recording unit that records an image captured by the imaging unit, and an analysis result of the spatial frequency analyzing unit in the recording unit The setting result can be recorded.
[0102]
【The invention's effect】
As described above, according to the present invention, it is possible to provide an imaging apparatus for a microscope that can always acquire a good image regardless of the microscopy method, the type of specimen, the observation magnification, and the like.
[Brief description of the drawings]
FIG. 1 is a diagram showing a schematic configuration of a first embodiment of the present invention.
FIG. 2 is a diagram showing three gradation characteristics stored in a gradation characteristic setting unit used in the first embodiment.
FIG. 3 is a flowchart for explaining the first embodiment;
FIG. 4 is a diagram illustrating a result of Fourier transform of image data according to the first embodiment.
FIG. 5 is a diagram illustrating a result of Fourier transform of image data according to the first embodiment.
FIG. 6 is a diagram illustrating a result of Fourier transform of image data according to the first embodiment.
FIG. 7 is a diagram showing a schematic configuration of a second embodiment of the present invention.
FIG. 8 is a diagram showing a schematic configuration of an edge emphasis processing unit used in the second embodiment.
FIG. 9 is a flowchart for explaining a second embodiment;
FIG. 10 is a diagram showing a schematic configuration of a third embodiment of the present invention.
FIG. 11 is a flowchart for explaining a third embodiment;
FIG. 12 is a diagram illustrating a result of Fourier transform of image data according to the third embodiment.
FIG. 13 is a diagram showing a schematic configuration of an example of a conventional microscope imaging apparatus.
FIG. 14 is a diagram showing a schematic configuration of another example of a conventional microscope imaging apparatus.
FIG. 15 is a diagram showing a schematic configuration of another example of a conventional microscope imaging apparatus.
[Explanation of symbols]
1 ... Microscope
2 ... Imaging device body
3. Light source for transmitted illumination
3a ... Optical path
4. Light source for epi-illumination
4a ... Optical path
5 ... Collector lens
6 ... Mirror
7 ... Window lens
8 ... FS (field stop)
9 ... AS (aperture stop)
10 ... Condenser lens
11 ... Sample
12 ... Objective lens
13 ... Imaging lens
14 ... Port
15 ... Cube unit
21 ... Image sensor
22: Image sensor driving unit
23 ... Pre-processing section
24 ... A / D converter
25. Signal processor
26 ... Spatial frequency analysis unit
27. Color correction processing unit
28 ... gradation correction processing section
29 ... Color correction parameter setting section
30 ... gradation characteristic setting section
31 ... D / A converter
32 ... Display section
33 ... Bus
34 ... Control unit
341: Pixel shift setting means
35 ... Recording section
36. Operation unit
41 ... contour enhancement processing unit
411: Edge extraction unit
412 ... Gain adjustment section
413 ... Outline emphasis part
42: Outline enhancement processing parameter setting unit
43 ... I / F section
44 ... PC
51. Pixel shifting means
52. Composition processing section

Claims (4)

Imaging means for imaging a specimen image obtained from a microscope;
Signal processing means having color correction means for performing color correction processing on image data of the specimen image captured by the imaging means and gradation correction means for performing gradation correction processing;
A luminance image is obtained from the image data picked up by the image pickup means, a first feature amount of the photographed image represented by a direct current component of the result of Fourier transformation of the luminance image is obtained, and the result of the Fourier transformation of the luminance image is obtained. A second feature amount of the photographed image represented by an integral value of a preset frequency range is obtained, and preset for each of the first and second feature amounts of the photographed image and the first and second feature amounts. A spatial frequency analysis means for outputting a result of comparing each of the threshold values,
And tone characteristic setting means for setting the gradation characteristics before Kikaicho correction means
Color correction parameter setting means for setting color correction parameters of the color correction means;
Comprising
Based on the analysis result by the spatial frequency analysis unit, at least the setting of the gradation characteristic of the gradation correction unit by the gradation characteristic setting unit and the setting of the color correction parameter of the color correction unit by the color correction parameter setting unit An imaging apparatus for a microscope , characterized in that one is made possible . Imaging means for imaging a specimen image obtained from a microscope;
A signal processing unit having a color correction unit that performs color correction processing on image data of the specimen image captured by the imaging unit, a gradation correction unit that performs gradation correction processing, and a contour enhancement processing unit that performs contour enhancement processing;
A luminance image is obtained from image data picked up by the imaging means, and a feature value of the photographed image represented by an integral value of a preset frequency range of a result of Fourier transform of the luminance image is obtained, and a feature amount of the photographed image is obtained. And a spatial frequency analyzing means for outputting a result of comparing a preset threshold value,
An imaging apparatus for a microscope, comprising: contour enhancement processing parameter setting means for setting processing parameters of the contour enhancement processing means based on an analysis result by the spatial frequency analysis means. Imaging means for imaging a specimen image obtained from a microscope;
Pixel shifting means for changing the relative position of the sample image and the imaging means;
An image processing means having a composition processing means for compositing image data picked up by the image pickup means at a plurality of positions when the relative position between the sample image and the image pickup means is changed by the pixel shifting means;
Spatial frequency analysis means for performing spatial frequency analysis of image data captured by the imaging means;
An image pickup apparatus for a microscope, comprising: a pixel shift setting unit that sets presence / absence of pixel shift by the pixel shift unit and presence / absence of synthesis processing by the synthesis processing unit based on an analysis result by the spatial frequency analysis unit . The spatial frequency analysis means obtains a luminance image from the image data imaged by the imaging means, and obtains a feature amount of the captured image represented by an integral value of a preset frequency range as a result of Fourier transform of the luminance image. ,
Based on the result of comparing the feature amount of the photographed image with a preset threshold value, the pixel shift setting unit can set whether or not the pixel shift unit is shifted and whether or not the combining process is performed. The imaging device for a microscope according to claim 3 , wherein the imaging device is a microscope.

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