JP4294257B2 - Camera, method of manufacturing camera, and focus correction adjustment apparatus - Google Patents

Description

【００７９】
【表２】

【００８０】
表１は、調整位置焦点距離データ群を示し、表２は、上記表１の各焦点距離位置に対応する調整位置調整値群を示している。ここで言う調整位置とは、前述した、基準位置をカメラ組立製造時に調整を行った焦点距離のことである。
【００８１】
本実施の形態では、上記表１に示すように調整位置焦点距離データとしてｆｐ（０）からｆｐ（１５）までの１６種類の焦点距離データをＥＥＰＲＯＭ２内部に記憶できるようになっており、これらの調整位置焦点距離データは、ＣＰＵ１による、図２のステップＳ３の処理によって、ＥＥＰＲＯＭ２からＣＰＵ１内部のＲＡＭに読み込まれることになる。
【００８２】
上記表１に示すｆｐ（０）からｆｐ（１５）までのそれぞれの調整位置焦点距離に対応する基準位置調整値は、表２に示すようにＳＰ（０）からＳＰ（１５）までの１６種類記憶できるようになっており、焦点距離ｆｐ（ｏ）での基準位置調整値はＳＰ（０）に対応し、ｆｐ（１）での基準位置調整値はＳＰ（１）に対応する、というように１対１にそれぞれ対応している。
【００８３】
基準位置調整値ＳＰ（０）からＳＰ（１５）は、カメラ組立製造時に、前述したｆｐ（０）からｆｐ（１５）のデータと共にＥＥＰＲＯＭ２に記憶される。記憶されていない焦点距離での基準位置調整値は、記憶されているデータを基に直線補完演算によって求めるようになっている。
【００８４】
以下、ズーミング駆動信号検出回路２５から出力された現在の焦点距離データ（焦点距離情報）をｆｐ、求める基準位置（ズームレンズの現在の焦点距離において、無限遠の被写体に対して合焦するための合焦レンズの位置）をＳＰとして、図５の基準位置繰り出し量算出処理について詳細に説明する。
【００８５】
図５は、図４のステップＳ６１に示す基準位置繰り出し量算出処理のサブルーチンを示すフローチャートである。
いま、ＣＰＵ１が図４に示すレンズ繰り出し量演算処理サブルーチン上の上記ステップＳ６１を実行すると、図５に示す基準位置繰り出し量算出処理のサブルーチンを起動し、つまり、ステップＳ７０の処理にて初期位置から基準位置への合焦レンズの繰り出し量算出の処理が開始される。
【００８６】
まず、ＣＰＵ１は、ステップＳ７１の処理にて、現在の焦点距離ｆｐが表１に示す調整位置焦点距離データ群の中のどの位置にあるかを調べるためのカウンター”ｎ”を０に初期化し、処理を続くステップＳ７１の判断処理に移行する。
【００８７】
ＣＰＵ１は、ステップＳ７２の判断処理にて、現在の焦点距離データｆｐが”ｎ＋１”番目の調整位置焦点距離データｆｐ（ｎ＋１）以下であるかどうかをチェックし、ｆｐがｆｐ（ｎ＋１）より大きいと判断した場合には、ｎの値をインクリメントし再び処理をステップＳ７２に戻す。
【００８８】
上記ステップＳ７２の判断処理にて、ｆｐがｆｐ（ｎ＋１）以下であるものと判断した場合には、ＣＰＵ１は、ｆｐの値がｆｐ（ｎ）とｆｐ（ｎ＋１）の間に存在することになり、補完演算を行うために次のステップＳ７４に処理を移行する。
【００８９】
ステップＳ７４の処理では、ＣＰＵ１は、ｆｐ（ｎ）と、対応する基準位置ＳＰ（ｎ）、ｆｐ（ｎ＋１）と、対応する基準位置ＳＰ（ｎ）、及び現在の焦点距離データｆｐを用いて、ｆｐに対応する基準位置繰り出し量ＳＰを直線補完演算により求める。
【００９０】
その後、ＣＰＵ１は、続くステップＳ７５により、該基準位置繰り出し量算出の処理を終了して、再び図４に示すレンズ繰り出し量演算処理ルーチンに処理を戻し、該ルーチン上の次のステップＳ６２へと処理を移行させる。
【００９１】
図４に示すように、次にＣＰＵ１は、ステップＳ６２の処理にて、基準位置から合焦位置（ズームレンズの現在の焦点距離において、実際の被写体に対して合焦するための合焦レンズの位置）までの繰り出し量を算出する。この場合の該ステップＳ６２による繰り出し量の算出処理の詳細を下記に示す表３及び図６を用いて説明する。
【００９２】
【表３】

【００９３】
表３は、被写体距離が無限遠のとき合焦する合焦レンズの繰り出し量である基準位置から、有限距離において実際の被写体に対して合焦する位置までの合焦レンズの繰り出し量を示す。
【００９４】
被写体距離の逆数に対応したデータＬＤＡＴＡは、図３に示す上記ステップＳ４１の測距処理によって得られるデータ（被写体距離情報）である。また、被写体距離毎の繰り出し量は焦点距離毎に異なるため、基準位置から合焦位置までの繰り出し量を算出する場合、被写体距離情報と、焦点距離情報とから、繰り出し量を求める必要がある。よって、上記表３は、焦点距離データと、被写体距離データとの組み合わせによって一つの繰り出し量が決定するデータ構造になっている。
【００９５】
但し、全ての入力データに対して出力データを決定できるだけのデータを持つと、膨大なデータになってしまうため、離散的な入力値に対するデータのみがＣＰＵ１内部のＲＯＭに記憶されるようになっている。よって、中間値の入力に対しては、記憶されているデータを基にして、直線補完演算によって、出力である繰り出し量を決定する。なお、上記表３に示すデータはＥＥＰＲＯＭ２に記憶しておいてもよい。
【００９６】
図６は、図４のステップＳ６２に示す基準位置から合焦位置までの繰り出し量算出処理のサブルーチンを示すフローチャートである。ＣＰＵ１は、図４のステップＳ６２の処理を実行すると、図６に示す基準位置から合焦位置までの繰り出し量算出処理のサブルーチンを起動し、つまり、ステップＳ８０から処理を開始させる。
【００９７】
ＣＰＵ１は、続くステップＳ８１の処理にて、まず、被写体距離データであるＬＤＡＴＡが、記憶されている被写体距離データ群のどの位置にあるかを調べるためのカウンターであるＸを０に初期化し、処理をステップＳ８２の判断処理に移行する。
【００９８】
ステップＳ８２の判断処理では、ＣＰＵ１は、被写体距離データＬＤＡＴＡが記憶されている被写体距離データ群の中のＬＤＡＴＡ（Ｘ＋１）以下であるかどうかの判断を行い、ＬＤＡＴＡがＬＤＡＴＡ（Ｘ＋１）以下であるものと判断した場合には、処理をステップＳ８３に移行し、該処理にてＸの値をインクリメントして、再びステップＳ８２に処理を戻す。
【００９９】
上記ステップＳ８２の判断処理において、ＣＰＵ１は、ＬＤＡＴＡの値がＬＤＡＴＡ（Ｘ＋１）より大きいものと判断した場合には、処理をステップＳ８４に移行する。つまり、ＬＤＡＴＡの値はＬＤＡＴＡ（Ｘ）より大きいものであって、ＬＤＡＴＡ（Ｘ＋１）以下となるＸの値が決定されることになる。
【０１００】
そして、ＣＰＵ１は、続くステップＳ８４の処理にて、焦点距離データｆｐが記憶されている焦点距離データ群のどの位置にあるかを調べるためのカウンターであるＹを０に初期化し、処理をステップＳ８５の判断処理に移行する。
【０１０１】
ステップＳ８５の判断処理では、ＣＰＵ１は、焦点距離データｆｐが記憶されている焦点距離データ群ｆｐＴ（Ｙ＋１）以下であるかどうかの判断を行い、ｆｐがｆｐＴ（Ｙ＋１）以下であるものと判断した場合には、Ｙの値をインクリメントして再びステップＳ８５に処理を戻す。
【０１０２】
上記ステップＳ８５の判断処理において、ＣＰＵ１は、ｆｐがｆｐＴ（Ｙ＋１）より大きいものと判断した場合には、処理をステップＳ８７に移行する。つまり、ｆｐの値はｆｐＴ（Ｙ）より大きいものであって、ｆｐＴ（Ｙ＋１）以下となるＹの値が決定されることになる。
【０１０３】
以上、求められたＸとＹを使用して、ＣＰＵ１は、上記表３の繰り出し量テーブルより、求める繰り出し量付近のデータを参照し、直線補完演算によって、繰り出し量を求めるように制御する。
【０１０４】
まず、ＣＰＵ１は、続くステップＳ８７の処理にて、焦点距離データｆｐ＝ｆｐＴ（Ｙ）のときの繰り出し量を直線補完によって算出し、算出結果をＯＢＪＰＬＳ１に格納するように制御する。
【０１０５】
その後、ＣＰＵ１は、続くステップＳ８８の処理にて、焦点距離データｆｐ＝ｆｐＴ（Ｙ＋１）であるときの繰り出し量を直線補間によって算出し、算出結果をＯＢＪＰＬＳ２に格納するように制御する。
【０１０６】
次に、ＣＰＵ１は、続くステップＳ８９にて、最終出力である焦点距離データｆｐに対応する基準位置から合焦位置までの繰り出し量ＯＢＪＰＬＳを、ＯＢＪＰＬＳ１とＯＢＪＰＬＳ２とから直線補完によって算出する。
【０１０７】
以上の処理を実行することにより、基準位置から合焦位置までの繰り出し量を求めることができたので、ＣＰＵ１は、続くステップＳ９０で該処理を終了し、図４のレンズ繰り出し量演算処理サブルーチンにリターンさせる。
【０１０８】
図４において、次にＣＰＵ１は、ステップＳ６３の処理にて、図５のステップＳ７４で求めた初期位置から基準位置までの繰り出し量ＳＰと、図６のステップＳ８９で求めた基準位置から合焦位置までの繰り出し量ＯＢＪＰＬＳを加算して、被写体距離データＬＤＡＴＡと焦点距離データｆｐに対応する合焦レンズの繰り出し量を演算し、リターンする（ステップＳ６４）。
【０１０９】
次に、本実施の形態におけるカメラ組立製造時の基準位置の調整方法について図７を参照しながら詳細に説明する。この調整は、カメラのＥＸＴ端子３を介して、カメラと外部装置とを通信可能になるように電気的に接続した状態で行う。
【０１１０】
図７は、本実施の形態の特徴となるカメラの組立製造時の、基準位置の調整値の決定方法を説明するため特性図である。
本実施の形態のカメラにおいては、カメラ組立製造時に、基準位置の調整を行う焦点距離データ（調整位置焦点距離データ）の決定と、上記調整位置焦点距離における基準位置調整値の決定とを行う。この場合、カメラの撮影レンズに平行光線を入射させ、焦点を結ぶ位置がフィルム面に対して前後方向のどの位置にあるかを示すΔＦＣ値の測定を行う。このΔＦＣ値を焦点距離毎に測定した結果が図７（ａ）に示されている。
【０１１１】
本実施の形態におけるカメラは、前述したようにカメラ内部のＥＥＰＲＯＭ２には、基準位置調整値を調整位置焦点距離データに対して離散的な値として記憶している。該カメラは、データを持たない焦点距離における調整値は、ＥＥＰＲＯＭ２に記憶されている基準位置調整値と、調整位置焦点距離データとに基づいて直線補完演算によって求めるようにしている。
【０１１２】
そこで、測定した各焦点距離データ毎のΔＦＣ値を基に、単位焦点距離データ当りのΔＦＣの変化量を求める。つまりΔＦＣ特性の微分値を求める。この微分値の特性を示したものが図７（ｂ）に示されている。
【０１１３】
図７（ｂ）において、ΔＦＣ特性の微分値が０となる焦点距離では、図７（ａ）のΔＦＣ特性における極値をとることになる。この極値となる焦点距離と、焦点距離範囲の両端であるワイド位置、テレ位置を基準位置の測定位置、つまり調整位置焦点距離とする。
【０１１４】
このように、少なくともΔＦＣ特性の極値を基準位置の測定位置とすることで、カメラ個々のΔＦＣ特性に合致した測定位置を決定することができる。
決定された測定位置でのΔＦＣの値から、それぞれの測定位置における合焦レンズの基準位置を求め基準位置調整値とする。そして、上記調整位置焦点距離と上記基準位置調整値とをカメラのＥＥＰＲＯＭ２に記憶させる。
【０１１５】
図７（ａ）に示すようなΔＦＣ特性を有する場合、極値を示す焦点距離データは４つであるので、まず、ｆｐ（０）としてワイド位置を示す焦点距離データを記憶させ、ｆｐ（１）からｆｐ（４）までにはそれぞれ極値を示す焦点距離データを記憶させ、ｆｐ（５）にはテレ位置を示す焦点距離データを記憶させる。
【０１１６】
そして、ＳＰ（０）からＳＰ（５）までには、ｆｐ（０）からｆｐ（５）に示された各焦点距離での基準位置調整値を記憶させる。つまり、ｆｐ（５）にテレ位置の焦点距離データ、ＳＰ（５）にテレ位置での基準位置調整値を記憶することで、基準位置の調整を行った数が決定することになる。
【０１１７】
本実施の形態では、組立製造時にΔＦＣ特性の測定を行った結果、極値が４つの場合であるので、前述した表１の調整位置焦点距離データ群の内ｆｐ（０）からｆｐ（５）までと、表２の基準位置調整値群の内ＳＰ（０）からＳＰ（５）までを記憶領域として使用することとなる。
【０１１８】
本発明に係る実施の形態においては、調整位置焦点距離データとしてｆｐ（０）からｆｐ（１５）までの１６種類の焦点距離データと、これらの焦点距離位置にそれぞれ対応するＳＰ（０）からＳＰ（１５）までの１６種類の基準位置データ等をＥＥＰＲＯＭ２内部に記憶できるように説明したが、これに限定されるものではなく、さらに詳細に各データを記憶しても良い。また、必要であればさらに他の情報を記憶し、用いるように構成しても良い。
【０１１９】
以上述べたように、本発明の実施の形態によれば、基準位置の調整を行う焦点距離データと基準位置調整値とをカメラ内部のＥＥＰＲＯＭ２内に記憶しているので、調整を行う焦点距離位置と数を任意に設定することが可能である。従って、設計段階で予測困難な合焦レンズのΔＦＣ特性に対して柔軟に対応することができ、より高精度のピント合わせの可能なズーム式カメラの実現が可能となる。
【０１２０】
また、上記実施の形態においては、極値を示す焦点距離データと該焦点距離における調整値を記憶手段に記憶するようにしたが、以下に示す変形実施も可能である。
【０１２１】
（１）ズームレンズの設計、組立バラツキ、部品バラツキによっては、一部の焦点距離領域で大きなズレが生じ場合がある。例えば図７（ａ）においては、ΔＦＣ値のＳＰ（０）からの移動量は、ワイド位置から焦点距離ｆｐ（２）までは小さく、焦点距離ｓｐ（３）からテレ位置（ｆｐ（５））までは大きい。このような場合には、ヒント位置の移動量が所定値よりも大きい焦点距離範囲の一部の領域での焦点距離データと調整値とを、記憶手段に記憶するようにしてもよい。また、上記移動量の比が所定値以上となる領域での焦点距離データと調整値とを記憶するようにしてもよい。
【０１２２】
（２）ズームレンズの設計によっては、望遠側（テレ側）の焦点距離領域で大きなズレが生じ場合がある。例えば図７（ａ）においては、ΔＦＣ値のＳＰ（０）からの移動量は、ワイド位置から焦点距離ｆｐ（２）までは小さく、焦点距離ｓｐ（３）からテレ位置（ｆｐ（５））までは大きい。このような場合には、所定の焦点距離（例えばｆｐ（２））よりも望遠側の領域での焦点距離データと調整値とを、記憶手段に記憶するようにしてもよい。また、このようなズームレンズにおいては、全ての焦点距離領域でΔＦＣ値を測定せずに、所定の一部の領域だけを測定ようにしてもよい。そうすることにより、測定時間の短縮が図られる。 このように、カメラにおける撮影可能な焦点距離領域の少なくとも一部の領域での焦点距離データと調整値とを、記憶手段に記憶することにより、繰り出し量の演算を高速化することができる。
【０１２３】
（３）始めに初期位置から基準位置までの繰り出し量を求め（第１演算）、次に、上記基準位置から合焦位置までの繰り出し量を求める（第２演算）。そして、上記２つの繰り出し量を加算して最終繰り出し量を決定している（第３演算）。ここで、上記第２演算については、表３に示したテーブルを用いる演算に代えて、所定の演算式を用いるようにしてもよい。
【０１２４】
なお、本発明は、上記実施の形態に限定されるもものではなく、その応用も本発明に含まれるものである。上記実施の形態に係るカメラはフィルムを使用するカメラであるが、撮像素子で撮像するデジタルカメラやビデオカメラなどの電子カメラ、テレビ用カメラ、携帯電話や情報携帯端末に接続したり搭載するカメラ、遠隔観察や遠隔撮影を行うカメラなど、多岐にわたるカメラへの応用が可能である。
【０１２５】
【発明の効果】
以上述べたように、本発明によれば、より高精度のピント合わせが可能であり、カメラの撮影性能の向上化を図ることのできるズームレンズ付きカメラを提供することができる。
【図面の簡単な説明】
【図１】 本発明のズームレンズ付きカメラの一実施形態を示し、該カメラの電気的構成を示すブロック図。
【図２】 図１に示すカメラのメインルーチンを示すフローチャート。
【図３】 図２に示すレリーズ処理のサブルーチンを示すフローチャート。
【図４】 図３に示すレンズ繰り出し量演算処理のサブルーチンを示すフローチャート。
【図５】 図４に示す基準位置繰り出し量算出処理のサブルーチンを示すフローチャート。
【図６】 図４に示す基準位置から合焦位置までの繰り出し量算出処理のサブルーチンを示すフローチャート。
【図７】 本実施の形態の特徴となるカメラの組立製造時の、基準位置の調整値の決定方法を説明するための特性図。
【符号の説明】
１…ＣＰＵ
２…ＥＥＰＲＯＭ
３…ＥＸＴ端子
４…ＰＷＳＷ
５…ＢＫＳＷ
６…ＲＷＳＷ
７…１ＲＳＷ
８…２ＲＳＷ
９…ＺＵＳＷ
１０…ＺＤＳＷ
１２…ストロボ回路部
１５…測距回路部
１６…赤外発光ダイオード
１７…投光レンズ
１８…受光素子
１９…受光レンズ
２０…測光回路部
２３…ズーミング回路部
２５…ズーミング駆動信号回路部
２６…フォーカシング駆動回路部
２８…フォーカシング駆動信号検出回路部
２９…シャッター駆動回路部
３１…シャッタ駆動信号検出回路部[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an autofocus (AF) camera with zoom, and more specifically, a focus position changes depending on a zoom position. Camera with zoom lens About.
[0002]
[Prior art]
Conventionally, a camera equipped with a zoom lens has a plurality of lens groups in a zoom lens barrel (lens frame), and the focal length is changed by changing the interval between each lens group, so that shooting can be performed at an arbitrary image magnification. It has a structure that can be done. In a zoom lens, when performing a zooming operation (focal length changing operation), the focal plane must always be constant regardless of the focal length position.
[0003]
In such a zoom lens, for example, when the rotating frame is rotated in a required direction, one lens group fixed to the lens frame by the linear helicoid mechanism is extended or retracted in the optical axis direction and rotated. By changing the interval between this lens group and the other lens groups by the rotation of the cam groove interlocking with the frame, the focal length is changed and zooming photography with a predetermined image magnification is possible.
[0004]
In addition, when performing a focusing operation (focusing operation), one of the above lens groups is linearly driven to slightly change the distance between the lens groups, and the focal position is imaged on a film surface, an image sensor surface, or the like. It is designed to be moved to the surface. The lens group that is driven when performing the focusing operation is called a focusing lens.
[0005]
In such a camera with a zoom lens, even if the subject distance is the same, if the focal length is different, the focus lens feed position differs, so the feed amount of the focus lens must be changed according to the focal length.
[0006]
Therefore, the present applicant has proposed a focus correction device for a camera with a zoom lens described in Japanese Patent Publication No. 7-95137. In the proposed focus correction apparatus, the payout amount curve from infinity to the closest time for each focal length is stored in the ROM in the CPU, and the focus lens extension amount is calculated from the focal length and subject distance data. Furthermore, it is possible to cope with this by having an EEPROM that stores deviation data caused by variations in lens assembly and lens component dimensions for each predetermined focal length. .
[0007]
By the way, with recent miniaturization and higher magnification of the camera, the lens configuration has a high FC sensitivity which is a ratio of a focal position change due to a change in the lens group interval. In such a lens configuration with high FC sensitivity, there is a possibility that the focal position may change greatly due to the helicoid mechanism supporting the lens group or slight unevenness of the cam groove.
[0008]
[Problems to be solved by the invention]
As described above, in the focus correction device for a camera with a zoom lens disclosed in the above-mentioned conventional Japanese Patent Publication No. 7-95137, the data stored in the EEPROM is stored in the focus lens at a plurality of predetermined focal lengths. As described above, in the recent lens configuration with high FC sensitivity, the focal position may change due to slight irregularities in the cam groove, as described above. It is difficult to determine whether or not to store the data, and there is a problem that the data for each predetermined focal length cannot be handled.
[0009]
Therefore, the present invention has been made in view of the above problems, and can focus more accurately and improve the shooting performance of the camera. Camera with zoom lens The purpose is to provide.
[0010]
[Means for Solving the Problems]
The camera according to claim 1, a photographing lens having a variable focal length; Focal length detection means for detecting the focal length of the photographing lens When,
Ranging means for measuring the distance of the subject When, A differential value is obtained by differentiating a reference position movement amount, which is a movement amount from the position where the photographing lens is normally standby for each focal length of the photographing lens to a position where the photographing lens is focused on an infinite object. The focal distance at which the value becomes zero and the reference position movement amount corresponding to the focal distance are stored, and further, the focal distance, a plurality of object distances, the focal distance, and the object distance are associated with each other. A memory for storing an in-focus position moving amount that is a moving amount from a reference position of the photographing lens to a position in which the subject is focused. When, Shooting from the initial position of the photographic lens to the reference position based on the focal length of the photographic lens output from the focal length detection means, the focal length stored in the memory, and the reference position movement amount stored in the memory First calculation means for calculating the lens movement amount When, Based on the focal length of the photographing lens output by the focal length detection means, the focal length stored in the memory, the in-focus position movement amount stored in the memory, and the subject distance output by the distance measuring means, Second calculating means for calculating the moving amount of the photographing lens from the reference position of the photographing lens to the position where the subject is focused. When, Based on the output of the first calculation means and the output of the second calculation means, third calculation means for calculating the photographing lens movement amount from the initial position of the photographing lens to the position where the subject is focused. It is characterized by having.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the invention will be described with reference to the drawings.
FIG. 1 is a block diagram showing an embodiment of a camera with a zoom lens according to the present invention, and showing an electrical configuration of the camera.
[0016]
As shown in FIG. 1, the camera with a zoom lens according to the present embodiment includes a CPU 1 as a control unit, and the CPU 1 is a microcomputer that performs various controls of the entire camera system according to the present embodiment.
[0017]
The CPU 1 includes EEPROM 2, EXT terminal 3, PWSW 4, BKSW 5, RWSW 6, 1RSW 7, 2RSW 8, ZUSW 9, ZDSW 10, LCD 11, strobe circuit section 12, ranging circuit section 15, photometry circuit section 20, zooming drive circuit section 23, zooming Drive signal detection circuit unit 25, focusing drive circuit unit 26, focusing drive signal detection circuit unit 28, shutter drive circuit unit 29, shutter drive signal detection circuit unit 31, film feed drive circuit unit 32, film movement amount detection circuit unit 34 And a film information detection circuit unit 35 are connected to each other.
[0018]
The EEPROM 2 is a non-volatile memory as a storage means for storing parameters and camera state necessary for controlling the camera.
The EXT terminal 3 is an external communication terminal for controlling the camera from the outside when performing various adjustments performed at the time of camera assembly and manufacturing for camera operation and performance assurance. An external device such as an automatic adjuster is connected to the camera via the EXT terminal 3 so that adjustment values and the like can be written to the EEPROM 2 in the camera. The EXT terminal 3 is used for communication with accessories such as an external strobe and a card memory when the camera is completed and used for photographing.
[0019]
PWSW4 is a switch for turning on and off the power of the camera. The on state indicates that the power is on, and the off state indicates that the power is off.
The BKSW 5 is a switch for detecting an open / close state of an unillustrated at-powder for loading and unloading a film. The on-state indicates an open-to-open state, and the off-state indicates an open-to-close state.
[0020]
The RWSW 6 is a switch for executing a forced rewinding of the film when it is normally turned off and is turned on.
The 1RSW 7 is a switch for starting a distance measurement operation and a photometry operation, which are exposure preparation operations, when it is normally turned off and is turned on. The distance measurement operation is an operation for generating subject distance information, and the photometry operation is an operation for generating subject luminance information.
[0021]
The 2RSW 8 is a switch for starting an exposure operation when it is normally turned off and is turned on. The 1RSW7 and 2RSW8 constitute a two-stage switch, and after the 1RSW7 is turned on, the 2RSW is turned on.
[0022]
The ZUSW 9 is a switch for starting zooming zooming so that the focal length is changed to the telephoto side (tele side) when the ZUSW 9 is normally turned off and is turned on.
[0023]
The ZDSW 10 is a switch for starting zooming driving of the zoom lens so as to change the focal length to the wide-angle side (wide side) when the ZDSW 10 is normally turned off and is turned on.
[0024]
The LCD 11 is an external display means for visually displaying information indicating an operation state such as a camera mode display and a frame number display. The display based on various information on the LCD 11 is controlled by the CPU 1. It has become.
[0025]
The strobe circuit unit 12 is connected to an Xe tube 13 that is a light source for illuminating a subject and a main capacitor 14 that stores electrical energy for illumination in order to keep exposure appropriately.
[0026]
An infrared light emitting diode 16 and a light receiving element 18 are connected to the distance measuring circuit section 15. The light from the infrared light emitting diode 16 is irradiated onto the subject 37 through the light projecting lens 17, and the reflected light from the subject 37 is received by the light receiving element 18 through the light receiving lens 19. The distance circuit unit 15 measures the distance from the camera to the subject according to the principle of triangulation. The distance measuring circuit 15, the infrared light emitting diode 16, the light projecting lens 17, the light receiving element 18 and the light receiving lens 19 are main components of the distance measuring means of the present invention. As the distance measuring means, an active method, a passive method, a phase difference method, a light amount detection method, or the like may be used.
[0027]
A light receiving element 21 is connected to the photometric circuit unit 20. In the photometric circuit unit 20, the light receiving element 20 detects the amount of light in the vicinity of the subject incident through the photometric lens 22 disposed in the vicinity of the light receiving element 20, and the subject brightness for determining the exposure condition is measured.
[0028]
The zooming drive circuit unit 23 drives the zoom motor 24 under the control of the CPU 1, and a rotational force is transmitted to a zooming optical system of a photographing lens (zoom lens) (not shown) via a gear train (not shown). Thus, the zooming operation is performed. Specifically, the focal length of the zoom lens is changed by changing the group interval of a plurality of lens groups constituting the zoom lens.
[0029]
The zooming drive signal detection circuit unit 25 generates a pulse signal corresponding to the rotation amount of the zoom motor 24 and transmits the pulse signal to the CPU 1. In response to this, the CPU 1 counts the pulse signals to generate data corresponding to the focal length.
[0030]
The focusing drive circuit unit 26 drives a focusing motor 27 under the control of the CPU 1, and performs a focusing operation by transmitting a rotational force to a focusing optical system (not shown) via a gear train (not shown). . Specifically, a focusing lens as a focusing optical system is driven in the optical axis direction so that the focal position (focusing position) matches the imaging surface.
[0031]
The focusing drive signal detection circuit unit 28 generates a pulse signal corresponding to the rotation amount of the focusing motor 27 and transmits the pulse signal to the CPU 1. In response to this, the CPU 1 detects the number and period of the pulse signals to perform control for accurately stopping the focusing lens at the focusing position.
[0032]
The shutter drive circuit unit 29 performs energization control to the plunger 30 for driving a shutter (not shown) under the control of the CPU 1. The CPU 1 controls the energization time of the plunger 30 to control the exposure amount.
[0033]
The shutter drive signal detection circuit unit 31 generates a reference timing for controlling the energization time of the plunger 30 in conjunction with a shutter operation (not shown) and transmits the reference timing to the CPU 1.
[0034]
The film feed drive circuit unit 32 drives the film feed motor 33 under the control of the CPU 1 and winds and rewinds the film.
The film movement amount detection circuit unit detects the perforation formed on the film (not shown) to detect the film feeding state and transmits the detection result to the CPU 1.
[0035]
The film information detection circuit unit 35 reads ISO sensitivity information provided in the film cartridge 36 and transmits it to the CPU 1.
Next, the operation of the camera of the present embodiment will be described in detail with reference to FIG. FIG. 2 is a flowchart showing a main routine executed by the CPU mounted on the camera of the present invention.
[0036]
Assume that the camera is turned on by turning on the PWSW 4 of the camera shown in FIG. Then, the CPU 1 of the camera shown in FIG. 1 starts the main routine (PWRST) shown in FIG. 2, that is, starts the operation from step S0.
[0037]
First, when the operation starts, the CPU 1 shifts the process to step S1, and performs initial setting in the step S1. In this case, the initial setting is a process for initializing the CPU 1 described above, and for example, initialization of each input / output port, RAM, and the like is performed.
[0038]
Thereafter, the CPU 1 shifts the process to step S2, and in step S2, controls to perform external communication with the accessory by the EXT terminal 3 described above, and shifts the process to the next step S3.
[0039]
In the process of step S3, the CPU 11 reads out the data stored in the EEPROM 2, performs control so as to store the data in the above-described RAM in the CPU 1, and shifts the process to the determination process of step S4. Examples of the data include adjustment position focal length data (see Table 1) and a reference position adjustment value (see Table 2) described later.
[0040]
In the determination process in step S4, it is determined whether or not the state of the BKSW 5 has changed. If it is determined that the state has changed, the process proceeds to step S5, and if it has been determined that it has not changed. In step S9, the process proceeds.
[0041]
If it is determined that the state of the BKSW 5 has changed, the CPU 1 determines whether or not the current state of the BKSW 5 is an off state in the determination process of step S5. If not, the process proceeds to step S6. Transition. In this case, since the state of the BKSW 5 has changed and the current state is on, the BKSW 5 has changed from off to on. In other words, it indicates that the at-pig has changed from the closed state to the open state. Therefore, the CPU 1 stores 0 in the flag F_BKCLOS indicating that the attobull is in the closed state when it is “1” in the process in step S6, and shifts the process to step S9. To do.
[0042]
On the other hand, if the state of BKSW5 is OFF in the determination process of step S5, the CPU 1 shifts the process to step S7, sets “1” to the flag F_BKCLOS described above, and The fact that it is in the closed state is memorized, and in the processing in the subsequent step S8, since the atto pig is changed from the open state to the closed state, there is a possibility that the film has been set. The process proceeds to step S9.
[0043]
If BKSW5 has not changed in the determination process of step S4, the CPU 1 changes the state of the flag F_WNDREQ indicating that one frame winding is necessary in the process of step S9. to decide. That is, when the state of F_WNDREQ is “1”, the CPU 1 shifts the process to step S10, performs a single frame winding operation in the process, and shifts the process to the determination process of step S11.
[0044]
In step S11, the CPU 1 determines whether or not a film end has been detected during winding of one frame in the process in step S10. If no film end has been detected, the process proceeds to step S13. If the film end is detected, the process proceeds to step S12.
[0045]
In the process of step S12, since the film end is detected, the rewinding operation is necessary. Therefore, the CPU 1 sets “1” to the flag F_RWREQ indicating that the rewinding is necessary, and the process To step S13.
[0046]
If the CPU 1 determines that the state of F_WNDREQ described above is “0” in the determination process of step S9, the process proceeds to step S13.
In the determination process in step S13, the CPU 1 determines the state of the flag F_RWREQ described above. If it is determined that F_RWREQ is “1”, it is necessary to perform rewinding. The advance / rewind process is performed, and then the process proceeds to step S15.
[0047]
In the determination process of step S13, the CPU 1 shifts the process to step S15 because rewinding is not necessary when F_RWREQ is determined to be “0”.
[0048]
In the determination process of step S15, the CPU 1 determines the state of the PWSW 4, and if it is determined that the state of the PWSW 4 is an off state, it indicates that the power is off. A retracting process for storing the lens frame in the camera body is performed, and control is performed to perform a display OFF process for turning off the LCD 11 in the next step S18.
[0049]
Thereafter, the CPU 1 performs a process of stopping the operation of the CPU 1 in the process of step S19, and shifts the operation of the CPU 1 to the stop state. In order to return from this stop state, the operation of the CPU 1 is restarted from step S0 which is the head of this routine by the operation of PWSW4, BKSW5 and RWSW6.
[0050]
On the other hand, when the CPU 1 determines that the PWSW 4 is in the on state in the determination processing in step S15, the CPU 1 indicates the power on state, and in step S16, the CPU 1 moves the lens frame to the wide position that is in the photographing state. After controlling to perform the setup process, the process proceeds to step S20.
[0051]
In the process of step S20, the CPU 1 detects the state change of each switch of PWSW4, BKSW5, RWSW6, 1RSW7, 2RSW8, ZUSW9 and ZUSW10 and the current state, and operates the LCD 11 in the subsequent process of step S21. Control is performed to execute display ON processing for performing necessary display.
[0052]
Thereafter, the CPU 1 determines whether or not the state of the PWSW 4 has changed in the subsequent determination process in step S22. If it is determined that the state has changed, the process proceeds to step S25, and PWRST (step S0), which is the head of this routine. Jump to).
[0053]
If it is determined in step S22 that the state of the PWSW 4 has not changed, the CPU 1 proceeds to step S23 and determines whether or not the state of the BKSW 5 has changed in the processing. Do. When determining that the state of the BKSW 5 has changed, the CPU 1 shifts the processing to step S25 and jumps to PWRST (step S0) which is the head of this routine as described above.
[0054]
If it is determined in step S23 that the state of the BKSW 5 has not changed, the CPU 1 shifts the processing to step S24 and determines whether or not the state of the RWSW 6 has changed in the processing. . When determining that the state of the RWSW 6 has changed, the CPU 1 shifts the processing to step S26, and determines whether or not the state of the RWSW 6 is currently on in the processing. When determining that the state of the RWSW 6 is the on state, the CPU 1 shifts the processing to step S27.
[0055]
In the determination process of step S27, the CPU 1 determines the state of the flag F_BKCLOS indicating the current state of the pig, and if it is determined that F_BKCLOS is “1”, the process proceeds to step S28. When F_BKCLOS is “1”, it indicates that the state of the piglet is closed. Therefore, here, when the piglet is in the closed state, the RWSW 6 is changed from the off state to the on state. That is, since the rewinding process is necessary, the CPU 1 sets “1” to the flag F_RWREQ indicating that the rewinding process is necessary in the process of step S28, and returns the process to step S9. Then, as described above, the branch to step S14 is performed by the determination in step S13, and the rewinding process is executed.
[0056]
In the determination process of step S27, when it is determined that F_BKCLOS is “0”, or in the determination process of step S26, RWSW is determined to be OFF, or in the determination process of step S24, If it is determined that the state of the RWSW 6 has not changed, the rewinding process is not required, so the CPU 1 shifts the process to step S29.
[0057]
In the process of step S29, the CPU 1 operates the strobe circuit unit 12 described above to control the main capacitor 14 to charge the energy for strobe light emission, and then the process proceeds to step S30.
[0058]
In the process of step S30, the CPU 1 controls to execute a process for performing external communication in the same manner as the process of step S2, and the process proceeds to step S31. In the determination process in step S31, the CPU 1 determines whether 1RSW 7 has changed from the off state to the on state. If it is determined that the 1RSW 7 has changed from the off state to the on state, the exposure preparation is performed in the subsequent process in step S32. Release processing for performing the operation and the exposure operation is performed. The release process will be described later (see FIG. 3).
[0059]
For example, when an exposure operation is performed during the release process, the CPU 1 sets “1” to a flag F_WNDREQ indicating that a winding operation is necessary during the release process, and follows the state of the F_WNDREQ. In order to perform the process, after executing the release process, the process returns to step S9. In the process, as described above, when F_WNDREQ is “1”, the process proceeds to step S10 and the single frame winding operation is performed. To control.
[0060]
If it is determined in step S31 that the 1RSW 7 has not changed from the off state to the on state, the CPU 1 moves the process to step S33, and one of ZUSW 9 and ZDSW 10 is determined in this determination processing. It is determined whether the state has changed from the off state to the on state. When it is determined that one of the ZUSW 9 and the ZDSW 10 has changed from the off state to the on state, the CPU 1 controls the zooming drive circuit unit 23 in the subsequent step S34, and performs a zoom drive process for performing a zoom control operation. After execution, the process returns to step S20.
[0061]
If it is determined in step S33 that neither ZUSW9 nor ZDSW10 has changed from the off state to the on state, the CPU 1 returns the process to step S20. That is, by returning the process to step S20, the above-described process is repeated, and a main loop is formed.
[0062]
Next, details of the release process in step S32 described above will be described in detail with reference to FIG. FIG. 3 is a flowchart showing a subroutine of the release process shown in FIG.
[0063]
Now, it is assumed that the CPU 1 has executed the release process in step S32 on the main routine shown in FIG. Then, the CPU 1 activates a release process subroutine shown in FIG. 3, that is, the release process is started from step S40.
[0064]
First, the CPU 1 executes distance measurement processing in step S41. In this distance measuring process, the distance measuring circuit 15 is controlled to measure the distance to the subject as described above. The CPU 1 controls to store the measured result as data proportional to the reciprocal of the distance in LDATA, which is a RAM in the CPU 1. That is, the subject distance information is generated by the distance measuring means.
[0065]
Thereafter, the CPU 11 performs photometry processing in the subsequent step S42. In the photometric process, the photometric circuit unit 22 is controlled to measure the subject brightness, and the process proceeds to step S43.
[0066]
In the process of step S43, the CPU 1 executes a lens extension amount calculation that calculates a focus lens extension amount necessary for focusing. This lens extension amount calculation processing will be described later in detail (see FIGS. 4 to 6).
[0067]
Then, after executing the lens extension calculation process, the CPU 1 proceeds to step S44 to continue the process, and executes the exposure amount calculation process in step S44. In the exposure amount calculation processing in step S44, the CPU 1 performs control so as to calculate the shutter control time and the strobe light emission amount based on the subject brightness measured in step S42.
[0068]
Next, the CPU 1 performs control so as to perform SW reading processing for detecting the states of 1RSW7 and 2RSW8 in the subsequent processing of step S45. The states of 1RSW7 and 2RSW8 read here are determined by the determination processing in subsequent steps S46 and S47.
[0069]
First, the CPU 1 determines whether or not 1RSW7 is turned off in the determination process of step 46, and if it is determined that 1RSW7 is turned off, the 2RSW8 is turned off without being turned on. In order to end the release operation, the process proceeds to step S52, where the release process is ended. On the other hand, if it is determined that 1RSW7 is not turned off, since the 1RSW7 is in an on state, the process proceeds to step S47, and the state of 2RSW8 is determined in this process.
[0070]
If the CPU 1 determines that the 2RSW 8 is not in the ON state in the determination process of step S47, the CPU 1 returns the process to step S45 again, and controls to perform the SW reading process. In the determination process of step S47, when the CPU 1 determines that the 2RSW 8 is in the on state, it is necessary to start the exposure operation, and thus the process proceeds to the next step S48.
[0071]
As described above, the processing from step S45 to step S47 is repeated until 1RSW7 is turned off or 2RSW8 is turned on by the processing from step S45 to step S47. Become.
[0072]
In the process of step S48, the CPU 1 executes the focusing lens extension control according to the driving amount (the extension amount) of the focusing lens calculated in step S43, and brings the photographing lens into a focused state.
[0073]
Thereafter, in the subsequent step S49, the CPU 1 controls the exposure operation according to the shutter control time and the flash emission amount calculated in the step S44, and then performs the exposure in the subsequent step S50. Since the operation is completed, control is performed so as to perform lens position reset control for returning the focusing lens to the initial position. This initial position is a predetermined position where the focusing lens is normally kept on standby.
[0074]
Then, in the subsequent step S51, the CPU 1 sets “1” to a flag F_WNDREQ indicating that the winding control is required to roll up the exposed photographing frame, and then proceeds to the subsequent step S52. End the release process and return.
[0075]
Next, the lens extension amount calculation processing executed in step S43 in FIG. 3 will be described in detail with reference to FIG. 4, FIG. 5, FIG. 6, Table 1, Table 2, and Table 3.
FIG. 4 is a flowchart showing a subroutine of the lens extension amount calculation process shown in FIG.
[0076]
Assume that the CPU 1 has executed the lens extension amount calculation processing in step S43 on the release processing subroutine shown in FIG. Then, the CPU 1 activates a subroutine of the lens extension amount calculation process shown in FIG. 4, that is, the lens extension amount calculation process is started from step S60.
[0077]
First, in step S61, the CPU 1 executes reference position extension amount calculation for calculating the extension amount of the focusing lens from the initial position to the reference position. The reference position here is the position of the focusing lens for focusing on a subject at infinity. Further, the feed amount corresponds to the feed amount from the initial position which is the normal standby position of the focusing lens. Here, details of the calculation process of the reference position feed amount in step S61 will be described with reference to Table 1, Table 2, and FIG.
[0078]
[Table 1]

[0079]
[Table 2]

[0080]
Table 1 shows an adjustment position focal length data group, and Table 2 shows an adjustment position adjustment value group corresponding to each focal length position in Table 1 above. The adjustment position referred to here is the focal length obtained by adjusting the reference position at the time of manufacturing and assembling the camera.
[0081]
In the present embodiment, as shown in Table 1, 16 types of focal length data from fp (0) to fp (15) can be stored in the EEPROM 2 as the adjustment position focal length data. The adjustment position focal length data is read from the EEPROM 2 into the RAM inside the CPU 1 by the process of the step S3 in FIG.
[0082]
The reference position adjustment values corresponding to the respective adjustment position focal lengths from fp (0) to fp (15) shown in Table 1 are 16 types from SP (0) to SP (15) as shown in Table 2. The reference position adjustment value at the focal length fp (o) corresponds to SP (0), the reference position adjustment value at fp (1) corresponds to SP (1), and so on. 1 to 1 respectively.
[0083]
The reference position adjustment values SP (0) to SP (15) are stored in the EEPROM 2 together with the above-described data of fp (0) to fp (15) when the camera is assembled and manufactured. The reference position adjustment value at the focal length that is not stored is obtained by straight line interpolation based on the stored data.
[0084]
Hereinafter, the current focal length data (focal length information) output from the zooming drive signal detection circuit 25 is fp, and a reference position to be obtained (for focusing on an infinite subject at the current focal length of the zoom lens). The reference position payout amount calculation process of FIG. 5 will be described in detail with SP of the focusing lens position) as SP.
[0085]
FIG. 5 is a flowchart showing a subroutine of reference position feed amount calculation processing shown in step S61 of FIG.
Now, when the CPU 1 executes step S61 on the lens extension amount calculation processing subroutine shown in FIG. 4, the reference position extension amount calculation processing subroutine shown in FIG. 5 is started, that is, from the initial position in step S70. Processing for calculating the amount of focusing lens to the reference position is started.
[0086]
First, in the process of step S71, the CPU 1 initializes a counter “n” for checking which position the current focal length fp is in the adjustment position focal length data group shown in Table 1 to 0, The process proceeds to the determination process in step S71.
[0087]
In the determination process of step S72, the CPU 1 checks whether or not the current focal length data fp is equal to or smaller than the “n + 1” th adjustment position focal length data fp (n + 1), and if fp is greater than fp (n + 1). If it is determined, the value of n is incremented and the process returns to step S72 again.
[0088]
If it is determined in step S72 that fp is equal to or less than fp (n + 1), the CPU 1 has a value of fp between fp (n) and fp (n + 1). In order to perform the complementary calculation, the process proceeds to the next step S74.
[0089]
In the process of step S74, the CPU 1 uses fp (n), the corresponding reference position SP (n), fp (n + 1), the corresponding reference position SP (n), and the current focal length data fp. A reference position feed amount SP corresponding to fp is obtained by linear interpolation calculation.
[0090]
Thereafter, in step S75, the CPU 1 ends the reference position feed amount calculation processing, returns the processing to the lens feed amount calculation processing routine shown in FIG. 4 again, and proceeds to the next step S62 on the routine. To migrate.
[0091]
As shown in FIG. 4, next, in the process of step S <b> 62, the CPU 1 moves the focus lens from the reference position (the focus lens for focusing on the actual subject at the current focal length of the zoom lens). The feed amount up to (position) is calculated. Details of the feed amount calculation processing in step S62 in this case will be described with reference to Table 3 and FIG.
[0092]
[Table 3]

[0093]
Table 3 shows the extension amount of the focusing lens from the reference position, which is the extension amount of the focusing lens that is focused when the subject distance is infinity, to the position that focuses on the actual subject at a finite distance.
[0094]
Data LDATA corresponding to the reciprocal of the subject distance is data (subject distance information) obtained by the distance measuring process in step S41 shown in FIG. Further, since the amount of extension for each subject distance differs for each focal length, when calculating the amount of extension from the reference position to the in-focus position, it is necessary to obtain the amount of extension from the subject distance information and the focal length information. Therefore, Table 3 has a data structure in which one feed amount is determined by a combination of focal length data and subject distance data.
[0095]
However, if there is enough data to determine the output data for all the input data, the data becomes enormous, so that only the data for the discrete input values is stored in the ROM inside the CPU 1. Yes. Therefore, for the input of the intermediate value, the feeding amount as the output is determined by the straight line interpolation calculation based on the stored data. The data shown in Table 3 may be stored in the EEPROM 2.
[0096]
FIG. 6 is a flowchart showing a subroutine for calculating a feed amount from the reference position to the in-focus position shown in step S62 of FIG. When the CPU 1 executes the process of step S62 in FIG. 4, the CPU 1 starts a subroutine for calculating a feed amount from the reference position to the in-focus position shown in FIG. 6, that is, starts the process from step S80.
[0097]
In the subsequent process of step S81, the CPU 1 first initializes X, which is a counter for examining where the LDATA, which is the subject distance data, is in the stored subject distance data group, to 0. Is shifted to the determination processing in step S82.
[0098]
In the determination processing in step S82, the CPU 1 determines whether or not LDATA (X + 1) or less in the subject distance data group in which the subject distance data LDATA is stored, and LDATA is LDATA (X + 1) or less. If it is determined, the process proceeds to step S83, the value of X is incremented in the process, and the process returns to step S82 again.
[0099]
In the determination process of step S82, if the CPU 1 determines that the value of LDATA is greater than LDATA (X + 1), the process proceeds to step S84. That is, the value of LDATA is larger than LDATA (X), and the value of X that is equal to or less than LDATA (X + 1) is determined.
[0100]
Then, in the subsequent process of step S84, the CPU 1 initializes Y, which is a counter for examining which position in the focal distance data group in which the focal distance data fp is stored, to 0, and the process proceeds to step S85. The process proceeds to the determination process.
[0101]
In the determination process in step S85, the CPU 1 determines whether or not the focal length data group fpT (Y + 1) is less than the stored focal length data fp, and determines that fp is less than or equal to fpT (Y + 1). In this case, the value of Y is incremented and the process returns to step S85 again.
[0102]
If the CPU 1 determines that fp is greater than fpT (Y + 1) in the determination process of step S85, the process proceeds to step S87. That is, the value of fp is larger than fpT (Y), and the value of Y that is equal to or less than fpT (Y + 1) is determined.
[0103]
As described above, using the obtained X and Y, the CPU 1 performs control so as to obtain the feed amount by linear interpolation calculation with reference to the data in the vicinity of the feed amount obtained from the feed amount table in Table 3 above.
[0104]
First, in the subsequent process of step S87, the CPU 1 calculates a feed amount when the focal length data fp = fpT (Y) by linear interpolation, and controls to store the calculation result in OBJPLS1.
[0105]
Thereafter, in the subsequent process of step S88, the CPU 1 calculates a feed amount when the focal length data fp = fpT (Y + 1) by linear interpolation, and controls to store the calculation result in OBJPLS2.
[0106]
Next, in a subsequent step S89, the CPU 1 calculates a feed amount OBJPLS from the reference position corresponding to the focal length data fp which is the final output to the in-focus position from OBJPLS1 and OBJPLS2 by linear interpolation.
[0107]
By executing the above processing, the amount of extension from the reference position to the in-focus position can be obtained, so the CPU 1 ends the processing in the subsequent step S90, and the lens extension amount calculation processing subroutine of FIG. Let me return.
[0108]
In FIG. 4, next, in the process of step S63, the CPU 1 sets the feed amount SP from the initial position to the reference position obtained in step S74 in FIG. 5 and the in-focus position from the reference position obtained in step S89 in FIG. The amount of extension OBJPLS up to is added to calculate the amount of extension of the focusing lens corresponding to the subject distance data LDATA and the focal length data fp, and the process returns (step S64).
[0109]
Next, a method for adjusting the reference position at the time of camera assembly manufacture in the present embodiment will be described in detail with reference to FIG. This adjustment is performed in a state where the camera and the external device are electrically connected via the EXT terminal 3 of the camera so as to be communicable.
[0110]
FIG. 7 is a characteristic diagram for explaining a method for determining the adjustment value of the reference position when assembling and manufacturing the camera, which is a feature of the present embodiment.
In the camera of the present embodiment, the focal length data (adjusted position focal length data) for adjusting the reference position and the reference position adjustment value at the adjusted position focal length are determined at the time of camera assembly and manufacturing. In this case, a parallel light beam is made incident on the photographing lens of the camera, and the ΔFC value indicating the position in the front-rear direction relative to the film surface is measured. The result of measuring this ΔFC value for each focal length is shown in FIG.
[0111]
As described above, the camera according to the present embodiment stores the reference position adjustment value as a discrete value with respect to the adjustment position focal length data in the EEPROM 2 inside the camera. In the camera, the adjustment value at the focal length without data is obtained by linear interpolation based on the reference position adjustment value stored in the EEPROM 2 and the adjustment position focal length data.
[0112]
Therefore, the amount of change in ΔFC per unit focal length data is obtained based on the measured ΔFC value for each focal length data. That is, the differential value of the ΔFC characteristic is obtained. FIG. 7B shows the characteristic of the differential value.
[0113]
In FIG. 7B, at the focal length where the differential value of the ΔFC characteristic is 0, the extreme value in the ΔFC characteristic of FIG. The extreme focal length, the wide position and the tele position, which are both ends of the focal length range, are used as the reference position measurement position, that is, the adjustment position focal length.
[0114]
In this way, by setting at least the extreme value of the ΔFC characteristic as the measurement position of the reference position, the measurement position that matches the ΔFC characteristic of each camera can be determined.
From the value of ΔFC at the determined measurement position, the reference position of the focusing lens at each measurement position is obtained and used as the reference position adjustment value. Then, the adjustment position focal length and the reference position adjustment value are stored in the EEPROM 2 of the camera.
[0115]
In the case of having the ΔFC characteristic as shown in FIG. 7A, since there are four focal length data indicating extreme values, first, focal length data indicating a wide position is stored as fp (0), and fp (1 ) To fp (4), focal length data indicating extreme values is stored, and fp (5) is stored focal length data indicating the tele position.
[0116]
Then, the reference position adjustment value at each focal length indicated by fp (0) to fp (5) is stored from SP (0) to SP (5). That is, by storing the focal length data of the tele position in fp (5) and the reference position adjustment value at the tele position in SP (5), the number of adjustments of the reference position is determined.
[0117]
In this embodiment, the ΔFC characteristic is measured at the time of assembling and manufacturing. As a result, there are four extreme values. Therefore, fp (0) to fp (5) in the adjustment position focal length data group in Table 1 described above. And SP (0) to SP (5) in the reference position adjustment value group in Table 2 are used as the storage area.
[0118]
In the embodiment according to the present invention, 16 types of focal length data from fp (0) to fp (15) as adjustment position focal length data, and SP (0) to SP corresponding to these focal length positions, respectively. Although it has been described that the 16 types of reference position data up to (15) can be stored in the EEPROM 2, the present invention is not limited to this, and each data may be stored in more detail. Further, other information may be stored and used if necessary.
[0119]
As described above, according to the embodiment of the present invention, since the focal length data for adjusting the reference position and the reference position adjustment value are stored in the EEPROM 2 in the camera, the focal length position for adjusting is adjusted. It is possible to arbitrarily set the number. Therefore, it is possible to flexibly cope with the ΔFC characteristic of the focusing lens, which is difficult to predict at the design stage, and it is possible to realize a zoom camera capable of focusing with higher accuracy.
[0120]
In the above-described embodiment, the focal length data indicating the extreme value and the adjustment value at the focal length are stored in the storage means. However, the following modifications are possible.
[0121]
(1) Depending on the design, assembly variation, and component variation of the zoom lens, a large deviation may occur in some focal length regions. For example, in FIG. 7A, the movement amount of the ΔFC value from SP (0) is small from the wide position to the focal length fp (2), and from the focal length sp (3) to the tele position (fp (5)). It is big until. In such a case, the focal length data and the adjustment value in a partial region of the focal length range in which the movement amount of the hint position is larger than a predetermined value may be stored in the storage unit. Further, the focal length data and the adjustment value in an area where the ratio of the movement amount is a predetermined value or more may be stored.
[0122]
(2) Depending on the design of the zoom lens, a large shift may occur in the focal length region on the telephoto side (tele side). For example, in FIG. 7A, the movement amount of the ΔFC value from SP (0) is small from the wide position to the focal length fp (2), and from the focal length sp (3) to the tele position (fp (5)). It is big until. In such a case, the focal length data and the adjustment value in the region on the telephoto side from a predetermined focal length (for example, fp (2)) may be stored in the storage means. In such a zoom lens, it is possible to measure only a predetermined part of the region without measuring the ΔFC value in all focal length regions. By doing so, the measurement time can be shortened. As described above, by storing the focal length data and the adjustment value in at least a part of the focal length region that can be photographed by the camera in the storage unit, it is possible to speed up the calculation of the feeding amount.
[0123]
(3) First, a feed amount from the initial position to the reference position is obtained (first calculation), and then a feed amount from the reference position to the in-focus position is obtained (second calculation). Then, the final feed amount is determined by adding the two feed amounts (third calculation). Here, for the second calculation, a predetermined calculation formula may be used instead of the calculation using the table shown in Table 3.
[0124]
Note that the present invention is not limited to the above-described embodiment, and the application thereof is also included in the present invention. Although the camera according to the above embodiment is a camera that uses a film, an electronic camera such as a digital camera or a video camera that captures an image with an image sensor, a camera for a television, a camera that is connected to or mounted on a mobile phone or an information portable terminal, It can be applied to a wide variety of cameras such as remote observation and remote shooting.
[0125]
【The invention's effect】
As described above, according to the present invention, it is possible to focus with higher accuracy and to improve the shooting performance of the camera. Camera with zoom lens Can be provided.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an embodiment of a camera with a zoom lens according to the present invention and showing an electrical configuration of the camera.
FIG. 2 is a flowchart showing a main routine of the camera shown in FIG.
FIG. 3 is a flowchart showing a release processing subroutine shown in FIG. 2;
4 is a flowchart showing a subroutine of lens extension amount calculation processing shown in FIG. 3;
FIG. 5 is a flowchart showing a subroutine of reference position feed amount calculation processing shown in FIG. 4;
6 is a flowchart showing a subroutine for calculating a feed amount from a reference position to an in-focus position shown in FIG. 4;
FIG. 7 is a characteristic diagram for explaining a method for determining a reference position adjustment value when assembling and manufacturing a camera, which is a feature of the present embodiment;
[Explanation of symbols]
1 ... CPU
2… EEPROM
3 ... EXT terminal
4 ... PWSW
5 ... BKSW
6 ... RWSW
7 ... 1RSW
8 ... 2RSW
9 ... ZUSW
10 ... ZDSW
12 ... Strobe circuit section
15 ... Distance measuring circuit
16. Infrared light emitting diode
17 ... Projection lens
18. Light receiving element
19. Light receiving lens
20: Photometric circuit section
23 ... Zooming circuit
25. Zooming drive signal circuit section
26. Focusing drive circuit section
28 ... Focusing drive signal detection circuit section
29 ... Shutter drive circuit section
31. Shutter drive signal detection circuit unit

Claims (6)

A variable focal length shooting lens;
A focal length detecting means for detecting a focal length of the photographing lens ;
Ranging means for measuring the distance of the subject ;
Differentiate the reference position movement amount, which is the amount of movement from the position where the shooting lens is normally waiting for the focal length of the shooting lens to the position where the shooting lens is focused on an infinite object. Stores the focal length at which the value becomes zero and the reference position movement amount corresponding to the focal length, and further corresponds to the focal length, a plurality of subject distances, the focal length, and the subject distance. A memory for storing an in-focus position moving amount that is a moving amount from the reference position of the photographing lens to a position for focusing on the subject ;
Shooting from the initial position of the photographic lens to the reference position based on the focal length of the photographic lens output from the focal length detection means, the focal length stored in the memory, and the reference position movement amount stored in the memory First calculating means for calculating a lens movement amount ;
Based on the focal length of the photographing lens output by the focal length detection means, the focal length stored in the memory, the in-focus position movement amount stored in the memory, and the subject distance output by the distance measuring means, Second calculating means for calculating a moving amount of the photographing lens from a reference position of the photographing lens to a position where the subject is focused ;
Based on the output of the first calculation means and the output of the second calculation means, third calculation means for calculating the photographing lens movement amount from the initial position of the photographing lens to the position where the subject is focused. When,
A camera characterized by comprising: The memory further stores focal lengths of the wide end and the tele end of the photographing lens and a reference position movement amount corresponding to the focal length, and further a focusing position corresponding to the focal length and the subject distance. The camera according to claim 1, wherein a movement amount is stored .   The camera according to claim 1, wherein the memory is a nonvolatile memory. The first calculation means includes an interpolation calculation based on a focal length of the photographing lens output from the focal length detection means, a focal distance stored in the memory, and a reference position movement amount stored in the memory. The camera according to claim 1, wherein the camera is characterized in that The second calculating means outputs the focal length of the taking lens output from the focal length detecting means, the focal length stored in the memory, the in-focus position movement amount stored in the memory, and the ranging means outputs The camera according to any one of claims 1 to 3, further comprising an interpolation calculation based on a moving amount from a reference position of the photographing lens to a position where the subject is focused based on a subject distance . The camera according to claim 1, wherein the third calculation unit includes an addition operation based on the output of the first calculation unit and the output of the second calculation unit .

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