JP3651963B2 - Camera system - Google Patents

Description

尚基準位置は第１の中間光学系の結像位置（ｒ₁₇）である。
このデーターから明らかなように、間隔Ｄ₁ ，Ｄ₂ ，Ｄ₃ を変化させることにより、第１の中間光学系の結像位置を基準にして、状態（Ａ）と状態（Ｂ）とで射出瞳位置を調整し得ることがわかる。
【００５３】
図６は前記の本発明の第２の実施例の光学系の他の例を示すものである。同様に図６（Ａ）はある撮影光学系を用いた場合の第１の中間光学系の状態を示し、図６（Ｂ）は（Ａ）における撮影光学系とは異なる他の撮影光学系を用いた時の第１の中間光学系の状態を示す図である。
【００５４】
この図に示す光学系のレンズデーターは、下記の通りである。

尚基準位置は第１の中間光学系の結像位置（ｒ₁₈）である。
上記光学系も、データー中のＤ₁ ，Ｄ₂ ，Ｄ₃ を変化させることにより使用する撮影光学系に対応してその射出瞳位置を補正し得る。
【００５５】
次に本発明の第３の実施例である前記の射出瞳位置の補正に関する具体的手段の他の例を備えた光学系を示す。この実施例では、中間光学系の結像位置付近に着脱可能にレンズを配置する方法、又はパワーの異なるレンズを交換可能に配置することによって射出瞳位置の補正を行なっている。
【００５６】
図７は上記の補正手段を示す概略図であってＬＳは撮影光学系、ＬＳ１第１のは中間光学系であり、ＣＬは射出瞳位置補正用レンズである。このように第１の中間光学系の結像位置付近に補正用レンズＣＬを配置することにより、軸外主光線を曲げることが出来、軸外主光線を第２の中間光学系ＬＳ２（リレーレンズＲＬ）に導くことが可能である。つまり撮影光学系の交換に応じて第１の中間光学系中の補正用レンズＣＬを挿脱して射出瞳位置の補正を可能にしたものである。
【００５７】
図７に示す第３の実施例の射出瞳位置の補正手段は、２段階の補正を行なうものであるが、パワーの異なる複数の補正用レンズを用いることによって多段階の補正が可能である。
【００５８】
図８は第３の実施例において多くの補正用レンズを交換可能とするもので、（Ａ）に示す第１の中間光学系ＬＳ１の結像位置付近に、（Ｂ）に示す通りの円盤上にパワーの異なる補正レンズＣＬ１，ＣＬ２，ＣＬ３，ＣＬ４を配置し、円板を回転させることにより、使用する撮影光学系に応じてレンズＣＬ１，ＣＬ２，・・・を選択することにより４段階に切換えて補正することが可能である。つまり補正レンズをターレット式で切換えるものである。
【００５９】
図９は射出瞳位置を補正するための更に他の具体的手段を示す概略図である。この図９においてレンズＣＬ５は、第１の中間光学系の結像位置近傍におかれた屈折力を機械的に変え得る透明弾性体例えば特開昭６２−１６３４０１号公報に示すようなシリコンゴムにて作成したもので、力を加えることによりレンズ形状を変化させてレンズの屈折力を変化させ軸外主光線の角度である射出瞳位置を切換えるようにしている。
【００６０】
この透明弾性体よりなるレンズの代りに、特開平４−３４５１２号公報に記載されているような液体レンズを用い、その屈折力を変化させることによっても同様に射出瞳位置の切換えが可能である。
【００６１】
または補正用レンズとして屈折力を電気的に変え得る液晶レンズを用いて同様に屈折力を変化させることも出来る。具体的には特開平４−３４５１２４号公報に記載されている液晶レンズを用い液晶の屈折率を変えることにより射出瞳位置を補正することが出来る。
【００６２】
次に第１の中間光学系ＬＳ１を挿入した時のファインダー光学系に対する影響について述べる。
【００６３】
前述のように第１の中間光学系ＬＳ１を撮影レンズユニット１とカメラ本体２との間に挿入したことにより像の倍率が変化する。具体的には第１の中間光学系により縮小倍すると云う働きをする。このように第１の中間光学系ＬＳ１を含む中間レンズユニットを装着することにより撮像側では画面サイズが変換される。一方観察側（ファインダー側）では、画角，倍率が変化する。つまり縮小倍する作用を有する第１の中間光学系を用いない図２０に示す従来の光学系の場合、被写体光は撮影光学系により撮像側ではフィルム面に結像されると共にファインダー側ではフィルム面に対応する位置に結像されるが、本発明ではこの縮小倍する作用を持つ第１の中間光学系を挿入するために撮影光学系ＬＳと第１の中間光学系とで構成される光学系は、元の撮影光学系のみの焦点距離とは異なる焦点距離となり、そのためファインダー側では第１の中間光学系挿入前と挿入後とでは撮影範囲とファインダー視野が異なり、又焦点距離がずれてしまう。
【００６４】
本発明では、第１の中間光学系を挿入した際のこのファインダー側に対する影響を解消するための手段を備えている点も特徴としている。
次に第４の実施例にもとづいてこのファインダー系に対する影響を解消するための手段を説明する。
【００６５】
図１０は、ファインダー系に対する影響を除去した本発明の第４の実施例の第１の中間光学系の構成を示す図であって、（Ａ）はクイックリターンミラー（反射光学系）をはね上げての撮像時、（Ｂ）はクイックリターンミラーを下げてファインダーにての観察時（フレーミングの時）の構成である。この図に示すように第１の中間光学系ＬＳ１は、レンズ群Ｇ１とレンズ群Ｇ２より形成し、これらレンズ群Ｇ１，Ｇ２を移動させ、撮影光学系の射出瞳位置からレンズ群Ｇ１までの距離Ｄ₁ 、レンズ群Ｇ１とレンズ群Ｇ２との間隔Ｄ₂ 、レンズ群Ｇ２から第１の中間光学系による像位置（撮影光学系と第１の中間光学系との合成の光学系による結像位置）までの距離Ｄ₃ を変化させ、これにより第１の中間光学系の焦点距離を変化させている。つまり図１０（Ａ）の状態では、撮影光学系と第１の中間光学系との合成の焦点距離を撮像時に合わせ、又図１０（Ｂ）の状態では、撮影光学系の焦点距離を変化させないようにする。
【００６６】
ここで図１０に示す第４の実施例の光学系のデーターを示す。

この実施例においては、上記データーに示す通りの値にＤ₁ ，Ｄ₂ ，Ｄ₃ を変化させ、撮影光学系と第１の中間光学系との合成の焦点距離は、撮像時［図１０（Ａ）］では５６mm、又観察時［図１０（Ｂ）］では１４０mmである。尚撮影光学系のみの焦点距離は１４０mmを想定している。このように、この第４の実施例は、ファインダー側では、撮影光学系と第１の中間光学系の合成の焦点距離が撮影光学系のみの焦点距離と同じ値であり、又撮像時の合成の焦点距離は５６mmと小になり縮小倍率になり、約０．４倍に縮小される。
【００６７】
図１１（Ａ），（Ｂ）は、本発明において、第１の中間光学系を挿入した時でもファインダーによる良好な観察を行ない得るように調整可能とした他の実施例である第５の実施例を示す概略図である。
【００６８】
この実施例は、第１の中間光学系を挿脱可能として上記調整を行なうようにしたものである。
【００６９】
図１１において、ＬＳは撮影光学系、ＬＳ１は第１の中間光学系、ＬＳ２は第２の中間光学系（リレーレンズ）で（Ａ）の撮像時には第１の中間光学系ＬＳ１を挿入して、撮影光学系ＬＳと第１の中間光学系ＬＳ１と第２の中間光学系ＬＳ２とにより被写体光を撮像素子上に結像する。この時クイックリターンミラー（反射光学系）Ｍ１ははね上げられている。又（Ｂ）は観察時であって第１の中間光学系は光路から外され又クイックリターンミラーＭ１が光路中に配置されてファインダーでの観察が行なわれる。この（Ｂ）においては第１の中間光学系ＬＳ１が光路から除かれているため、光学系の焦点距離は、撮影光学系の焦点距離そのものである。
【００７０】
図１２は、第４，第５の実施例において焦点距離の切換えのタイミングを示す図である。この図において、（ａ）はレリーズでａ１がオン、（ｂ）はレンズシャッターの開閉でｂ１が閉じた時、ｂ２が開いた時、（ｃ）はミラー位置でｃ１がアップでｃ２がダウン更に（ｄ）は焦点距離の切換えでｄ１は撮像時でｄ２は観察時である。
【００７１】
図１２においてレリーズ前は、シャッター（ｂ）はｂ２にあり開いており、ミラー（ｃ）はｃ２にあり下りており、焦点距離（ｄ）は観察時であるｄ２になっており、被写体光はファインダー側へ達し又ファインダーでの観察が可能である。この状態でｔ₁ の時点でレリーズ（ａ）をオン（ａ１）にするとその後ｔ₂ にてシャッターが閉じ（ｂ１）、続いてｔ₃ にてミラー（ｃ）はｃ₂ からｃ₁ に変わりアップされ又焦点距離（ｄ）はｄ２からｄ１に変わり撮像時の焦点距離に変わる。更にｔ₄ においてシャッター（ｂ）がｂ１からｂ２により開かれて被写体光は撮像側に進み撮像される。撮像終了後のｔ₅ においてシャッターが閉じ又ｔ₆ においてミラーはダウンし焦点距離は観察側に変わり、ｔ₇ にてシャッターが開き元の状態にもどる。
【００７２】
本発明のカメラシステムのように、撮影レンズユニットの後ろに中間レンズユニットを挿入して撮影光学系の後方に第１の中間光学系を配置し場合、この第１の中間光学系により撮影光学系による像が縮小されて光路中に結像される。このような光学系においてファインダー側で観察する場合、ファインダー側にも小さな像が結像されるので、通常のファインダーでは観察しにくい。
【００７３】
この問題を解決するために、本発明ではファインダー側又は撮像ユニット内の撮像面側に光路を切換えるための反射光学系をおき反射されたファインダー側の光学系に、第１の中間光学系にて縮小された像を拡大させて再結像させる役割を持たせている。
【００７４】
図１３は、前記のファインダー側の像を拡大するための第６の実施例の光学系を示す図である。この図１３においてＬＳは撮影光学系、Ｓ１はその射出瞳、ＬＳ１は第１の中間光学系、Ｍ１，Ｍ２は光路をファインダー側へ向ける反射鏡（反射光学系）、ＬＳ３はファインダー用光学系、Ｉ３はファインダー用光学系ＬＳ３により結像された拡大像で、これにより拡大された観察しやすいファインダーを構成する。
【００７５】
この第６の実施例の光学系のデーターは次の通りである。
ｒ₀ ＝∞ ｄ₀ ＝∞
ｒ₁ ＝∞ ｄ₁ ＝10.0000
ｒ₂ ＝∞ ｄ₂ ＝46.0141
ｒ₃ ＝-85.6434 ｄ₃ ＝7.1570 ｎ₁ ＝1.77520 ν₁ ＝49.60
ｒ₄ ＝-57.3801 ｄ₄ ＝3.0473
ｒ₅ ＝339.1009 ｄ₅ ＝5.7618 ｎ₂ ＝1.77250 ν₂ ＝49.60
ｒ₆ ＝-169.5222 ｄ₆ ＝2.9063
ｒ₇ ＝55.0218 ｄ₇ ＝10.0561 ｎ₃ ＝1.77250 ν₃ ＝49.60
ｒ₈ ＝454.8651 ｄ₈ ＝2.9491 ｎ₄ ＝1.69895 ν₄ ＝30.12
ｒ₉ ＝101.3179 ｄ₉ ＝52.0001
ｒ₁₀＝∞ ｄ₁₀＝-50.5019
ｒ₁₁＝-89.3557 ｄ₁₁＝-8.0973 ｎ₅ ＝1.83400 ν₅ ＝37.17
ｒ₁₂＝155.6836 ｄ₁₂＝-0.2000
ｒ₁₃＝-24.1732 ｄ₁₃＝-13.3283 ｎ₆ ＝1.77250 ν₆ ＝49.60
ｒ₁₄＝233.3051 ｄ₁₄＝-3.1675 ｎ₇ ＝1.69895 ν₇ ＝30.12
ｒ₁₅＝-13.4856 ｄ₁₅＝-17.0484
ｒ₁₆＝13.4337 ｄ₁₆＝-3.0292 ｎ₈ ＝1.63980 ν₈ ＝34.48
ｒ₁₇＝816.1918 ｄ₁₇＝-9.3085 ｎ₉ ＝1.63854 ν₉ ＝55.38
ｒ₁₈＝23.1101 ｄ₁₈＝-1.2872
ｒ₁₉＝67.1623 ｄ₁₉＝-4.4975 ｎ₁₀＝1.56907 ν₁₀＝71.30
ｒ₂₀＝28.4103 ｄ₂₀＝-25.0000
ｒ₂₁＝∞ ｄ₂₁＝178.9927
ｒ₂₂＝∞
上記データー中ｒ₁₀は反射鏡Ｍ₁ 、ｒ₂₁は反射鏡Ｍ₂ 、ｒ₂₂はファインダー用光学系による結像位置である。又第１の中間光学系ＬＳ１の結像倍率は０．４０、ファインダー用光学系ＬＳ３の結像倍率は，−２．５である。
【００７６】
このように第１の中間光学系により縮小された像をファインダー用光学系により拡大して観察することが出来る。
【００７７】
図１４は他のファインダー用光学系を示す図である。図においてクイックリターンミラー（反射鏡Ｍ１）までは、図１３に示す光学系と同じである。又ファインダー側の光学系は、光学系ＬＳ３およびレンズ群Ｇ１，Ｇ２よりなる接眼光学系ＥＬとにて構成されている。又Ｍ２は図１３と同様反射鏡である。
【００７８】
この実施例の光学系では、第１の中間光学系ＬＳ１から射出した光は、反射鏡Ｍ１にて反射され光学系ＬＳ３により同じ倍率で接眼光学系ＥＬのレンズ群Ｇ１付近に再結像される。更に接眼光学系ＥＬにより像が拡大観察される。
【００７９】
この実施例のデーターは、下記の通りである。
ｒ₀ ＝∞ ｄ₀ ＝∞
ｒ₁ ＝∞ ｄ₁ ＝10.0000
ｒ₂ ＝∞（絞り） ｄ₂ ＝46.0141
ｒ₃ ＝-85.6434 ｄ₃ ＝7.1570 ｎ₁ ＝1.77520 ν₁ ＝49.60
ｒ₄ ＝-57.3801 ｄ₄ ＝3.0473
ｒ₅ ＝339.1009 ｄ₅ ＝5.7618 ｎ₂ ＝1.77250 ν₂ ＝49.60
ｒ₆ ＝-169.5222 ｄ₆ ＝2.9063
ｒ₇ ＝55.0218 ｄ₇ ＝10.0561 ｎ₃ ＝1.77250 ν₃ ＝49.60
ｒ₈ ＝454.8651 ｄ₈ ＝2.9491 ｎ₄ ＝1.69895 ν₄ ＝30.12
ｒ₉ ＝101.3179 ｄ₉ ＝52.0001
ｒ₁₀＝∞ ｄ₁₀＝-101.1950
ｒ₁₁＝-66.3150 ｄ₁₁＝-8.0907 ｎ₅ ＝1.83400 ν₅ ＝37.17
ｒ₁₂＝675.3393 ｄ₁₂＝-0.2000
ｒ₁₃＝-24.2696 ｄ₁₃＝-13.4254 ｎ₆ ＝1.77250 ν₆ ＝49.60
ｒ₁₄＝439.1123 ｄ₁₄＝-3.1588 ｎ₇ ＝1.69895 ν₇ ＝30.12
ｒ₁₅＝-12.9765 ｄ₁₅＝-16.8685
ｒ₁₆＝13.7225 ｄ₁₆＝-3.3430 ｎ₈ ＝1.63980 ν₈ ＝34.48
ｒ₁₇＝-65.8002 ｄ₁₇＝-9.3438 ｎ₉ ＝1.63854 ν₉ ＝55.38
ｒ₁₈＝23.0053 ｄ₁₈＝-2.5776
ｒ₁₉＝85.2345 ｄ₁₉＝-5.4035 ｎ₁₀＝1.56907 ν₁₀＝71.30
ｒ₂₀＝30.3318 ｄ₂₀＝-40.0000
ｒ₂₁＝∞ ｄ₂₁＝61.2877
ｒ₂₂＝-42.6404 ｄ₂₂＝4.0000 ｎ₁₁＝1.77250 ν₁₁＝49.60
ｒ₂₃＝-58.6786 ｄ₂₃＝0.2000
ｒ₂₄＝192.4150 ｄ₂₄＝8.0000 ｎ₁₂＝1.77250 ν₁₂＝49.60
ｒ₂₅＝-54.1481 ｄ₂₅＝67.1580
ｒ₂₆＝24.2145 ｄ₂₆＝2.0000 ｎ₁₃＝1.71736 ν₁₃＝29.51
ｒ₂₇＝21.8905 ｄ₂₇＝2.0000
ｒ₂₈＝33.3280 ｄ₂₈＝5.0000 ｎ₁₄＝1.62280 ν₁₄＝57.06
ｒ₂₉＝203.6289 ｄ₂₉＝94.9900
ｒ₃₀＝∞
このデーターの光学系は、第１の中間光学系の結像倍率は、図１３の光学系と同じ０．４倍、光学系ＬＳ３による結像倍率は１倍、又接眼光学系の焦点距離は６５mmである。
【００８０】
上記データー中、ｒ₁ は撮影光学系ＬＳ、ｒ₂ は絞り、ｒ₃ 〜ｒ₉ は第１の中間光学系ＬＳ１、ｒ₁₀は反射鏡Ｍ１、ｒ₁₁〜ｒ₂₀はファインダー光学系ＬＳ３、ｒ₂₁は反射鏡Ｍ２、ｒ₂₂〜ｒ₂₉は接眼光学系で、ｒ₃₀はアイポイント位置である。
【００８１】
図１５の（Ａ），（Ｂ）は他の第８の実施例の概略図で、（Ａ）は撮像ユニットがカメラ本体内に挿入された状態、（Ｂ）はカメラ本体と撮像ユニットが切り離された状態を示す図である。この実施例は、図１に示す第１の実施例と同じ構成であるが、この実施例では撮像ユニット４を取付け用挿入部４ｂをもって取付けた構成とし、この取付け用挿入部４ｂを含む撮像ユニット４内に第２の中間光学系（リレーレンズＬＳ２）の一部分（先方の部分）を配置した構成である。
【００８２】
この第８の実施例では、観察の際は、撮影レンズユニット１、中間レンズユニット１０、カメラ本体２のみを用い、クイックリターンミラーＭ１を下げてファインダー３による観察を行なう。又撮像時は、図１５（Ｂ）に示すようにカメラ本体２のクイックリターンミラーＭ１をはね上げた状態とし、（Ａ）のように撮像ユニット４の取付け用挿入部４ｂをカメラ本体内に挿入してカメラ本体に固定する。この状態にて撮影光学系と第１の中間光学系と第２の中間光学系との合成された光学系により被写体光が撮像素子の受光面上に結像されるように構成されている。つまり第２の中間光学系による再結像位置が前記受光面となるように第２の中間光学系が構成されている。
【００８３】
この実施例で用いられる第２の中間光学系の一例を示すと図１６に示す。又このレンズデーターは、次の通りである。
ｒ₀ ＝∞ ｄ₀ ＝∞
ｒ₁ ＝∞ ｄ₁ ＝10.0000
ｒ₂ ＝∞ ｄ₂ ＝42.3094
ｒ₃ ＝-41.4782 ｄ₃ ＝10.1468 ｎ₁ ＝1.51633 ν₁ ＝64.15
ｒ₄ ＝-37.8262 ｄ₄ ＝8.0223
ｒ₅ ＝108.6632 ｄ₅ ＝10.4838 ｎ₂ ＝1.77250 ν₂ ＝49.60
ｒ₆ ＝-103.0068 ｄ₆ ＝0.4924
ｒ₇ ＝30.6846 ｄ₇ ＝16.1745 ｎ₃ ＝1.60311 ν₃ ＝60.68
ｒ₈ ＝-418.3918 ｄ₈ ＝3.2298 ｎ₄ ＝1.80518 ν₄ ＝25.43
ｒ₉ ＝48.9807 ｄ₉ ＝31.1212
ｒ₁₀＝-25.8909 ｄ₁₀＝2.2000 ｎ₅ ＝1.48749 ν₅ ＝70.21
ｒ₁₁＝74.5986 ｄ₁₁＝10.9097
ｒ₁₂＝2625.6601 ｄ₁₂＝13.2936 ｎ₆ ＝1.77250 ν₆ ＝49.60
ｒ₁₃＝-33.6700 ｄ₁₃＝1.6246
ｒ₁₄＝44.4341 ｄ₁₄＝16.9630 ｎ₇ ＝1.83400 ν₇ ＝37.17
ｒ₁₅＝227.6967 ｄ₁₅＝4.7771
ｒ₁₆＝-43.0586 ｄ₁₆＝2.8977 ｎ₈ ＝1.60342 ν₈ ＝38.02
ｒ₁₇＝31.3949 ｄ₁₇＝7.1531
ｒ₁₈＝∞（絞り） ｄ₁₈＝9.1042
ｒ₁₉＝-19.4177 ｄ₁₉＝1.7983 ｎ₉ ＝1.72825 ν₉ ＝28.46
ｒ₂₀＝-60.4697 ｄ₂₀＝8.4471 ｎ₁₀＝1.81600 ν₁₀＝46.62
ｒ₂₁＝-29.6940 ｄ₂₁＝1.8512
ｒ₂₂＝-81.8550 ｄ₂₂＝2.4404 ｎ₁₁＝1.69895 ν₁₁＝30.12
ｒ₂₃＝-222.0465 ｄ₂₃＝12.2354 ｎ₁₂＝1.81600 ν₁₂＝46.62
ｒ₂₄＝-55.6437 ｄ₂₄＝0.2000
ｒ₂₅＝246.1377 ｄ₂₅＝12.2716 ｎ₁₃＝1.56907 ν₁₃＝71.30
ｒ₂₆＝-67.0378 ｄ₂₆＝0.2449
ｒ₂₇＝99.1945 ｄ₂₇＝7.8527 ｎ₁₄＝1.56907 ν₁₄＝71.30
ｒ₂₈＝-231.6542 ｄ₂₈＝0.2000
ｒ₂₉＝54.3321 ｄ₂₉＝13.6397 ｎ₁₅＝1.48749 ν₁₅＝70.21
ｒ₃₀＝-79.3281 ｄ₃₀＝1.8361 ｎ₁₆＝1.72825 ν₁₆＝28.46
ｒ₃₁＝93.9123 ｄ₃₁＝4.6019
ｒ₃₂＝∞ ｄ₃₂＝5.0000 ｎ₁₇＝1.51633 ν₁₇＝64.15
ｒ₃₃＝∞ ｄ₃₃＝1.0000
ｒ₃₄＝∞ ｄ₃₄＝55.0000 ｎ₁₈＝1.58267 ν₁₈＝46.39
ｒ₃₅＝∞ ｄ₃₅＝4.9813
ｒ₃₆＝∞
図１６に示す光学系およびこの光学系のデーターにおいて、ｒ₁ は撮影光学系ＬＳ、ｒ₂ は絞り、ｒ₃ 〜ｒ₉ は第１の中間光学系ＬＳ１、ｒ₁₀〜ｒ₃₁は第２の中間光学系ＬＳ２、ｒ₃₂〜ｒ₃₃は赤外線カットフィルター等の光学素子、ｒ₃₄〜ｒ₃₅は３色分解プリズムであり、又ｒ₁₈は第２の中間光学系の絞りである。
【００８４】
前記のように図１６およびデーターは、撮影光学系、中間光学系を含めて示してある。この図およびデーターに示すように、この実施例では、図１６に示すようにカメラ本体内に撮像ユニットの一部（取付け用挿入部）を挿入することにより、第２の中間光学系を第１の中間光学系に近接配置した設計になし得る。つまり第１の中間光学系ＬＳ１と第２の中間光学系ＬＳ２との間隔ｄ₄ が比較的小になっている。これによって、第２の中間光学系の一部をカメラ本体内に挿入した状態にて被写体光を撮像素子の受光面上に結像させることが出来る。つまり、撮像ユニットの奥行を短縮出来る。この図１４に示す光学系の第１の中間光学系の結像面から第２の中間光学系の結像面（撮像素子の受光面）までの距離は、１４５mmである。
【００８５】
図１７は、上記第８の実施例における撮像ユニット４の取付け用挿入部の挿入とクイックリターンミラーの切換えとその他の制御について示す図である。
【００８６】
図において左上に示すカメラ本体２等が図１６（Ａ）に示す第８の実施例の取付け用挿入部を挿入した状態を示し、これに対し制御用の電気回路系をブロック図として示してある。この回路図において、１２は撮像回路、１３は信号変換回路、１４は表示駆動部、１５はＣＰＵ、１６はトリガー回路、１７はＣＣＤ駆動部、１８は挿入駆動部、１９はミラー制御部、２０はディスプレイ表示部である。
【００８７】
図において、３色分解フィルターＰ１の後方に配置された撮像素子１１よりの信号は撮像回路１２に入力される。この信号は撮像回路１２にて撮像処理されて信号処理回路１３へ出力される。一方撮像回路１２で信号処理された表示用の信号は、ディスプレイ用の信号に変換されてディスプレイの駆動回路１４を経由してディスプレイ２０に表示される。
【００８８】
一方、カメラ本体２には挿入検出部（図示してない）が配置されており、撮像ユニット４の取付け挿入部が挿入されると、カメラ本体２の接続部２ｂおよび撮像ユニット４の接続部４ａにメカスイッチ（図示してない）が設けられている。そして撮像ユニット４の取付け用挿入部がカメラ本体２内に挿入されるとメカスイッチがオン状態になる構成にしてある。このオン信号を挿入検知部１８が検知すると信号がＣＰＵ１５へ送られる。ＣＰＵ１５は、この検知信号を認識しミラー制御を行ないクイックリターンミラーをはね上げる。同時にＣＰＵ１５よりの信号にもとづいて、表示駆動が行なわれ、被写体光に基づいた画像がディスプレイ１４に表示可能となる。
【００８９】
上記のようにＣＰＵ１５により制御が行なわれるが、この制御をフローチャートで示したのが図１８である。この図に示すように、シーケンスが始まると、撮像ユニットがカメラ本体に接続されたか否かを判断する（１８１）。撮像ユニットが接続されていない時は、そのまま制御を終了する。撮像ユニットが接続されている時には、前述のようにミラーをはね上げて固定し、又ディスプレイ２０の表示回路１４を駆動し、その後終了する。
【００９０】
図１９は、第９の実施例の構成を示す概略図である。この実施例は、光学系の光路を９０°曲げることによって撮像ユニットの奥行方向の長さを更に短くした例である。即ち、この実施例においては、撮像ユニット４内に反射光学系Ｍ３を配置することによりカメラ本体より射出し撮像ユニットに入射する被写体光の光路を反射させて９０°曲げ図面下方に向けるようにしたもので、これによって撮像ユニットの奥行方向つまり撮影光学系の光軸に沿った方向の長さを短くしている。
【００９１】
【発明の効果】
（１）本発明の請求項１のカメラシステムは、大きな画面サイズの撮影光学系を利用して小型の撮像素子上に撮像するもので、撮像ユニットの奥行の寸法が小で、バランスの良い装置になし得るものである。又ファインダー像が見やすく、良好な撮像が可能なカメラシステムを実現し得る。
（２）本発明の請求項２の中間レンズユニットは、大きな画面サイズの撮影光学系を利用して小型の撮像素子上に撮像するカメラシステムに用いれば、カメラシステムにおける、撮像ユニットの奥行の寸法を小になし得、バランスの良い装置になし得るものである。又ファインダー像が見やすく、良好な撮像が可能なカメラシステムを実現し得る。
（３）本発明の請求項３の撮像ユニットは、大きな画面サイズの撮影光学系を利用して小型の撮像素子上に撮像するカメラシステムに用いれば、撮像ユニットの奥行の寸法が小で、バランスの良い装置になし得るものである。又ファインダー像が見やすく、良好な撮像が可能なカメラシステムを実現し得る。
（４）請求項４の発明によれば異なる種類の撮影レンズユニットの撮影光学系による画面周辺部の光量落ち特性（周辺光量特性）変化が少なくなる。撮像ユニットが色分解ダイクロイックプリズムを含む場合は、プリズムへの斜入射による画面内の色むらを防ぐことが出来る。
（５）請求項５の発明によれば、請求項４の発明による効果に加え、レンズの移動に応じ、無段階に射出瞳位置を補正出来る。
（６）請求項６の発明によれば光軸方向の移動スペースを確保する必要がないので、請求項４の発明による効果に加え、中間レンズユニットの光軸方向の寸法を小型化出来る。
（７）請求項７の発明によれば光軸方向の移動スペースを確保する必要がないので、中間レンズユニットの寸法が小型化出来る。又レンズの移動に応じ、無段階に射出瞳位置を補正出来る。
（８） 請求項８の発明によれば、撮像ユニットの奥行き寸法が小さくなり、且つ撮影範囲とファインダ視野が一致する。又ファインダ側結像位置が、中間レンズユニットの有無によって変化しない。
（９） 請求項９の発明によれば光軸のみの移動なので請求項８の発明による効果に加え、中間光学系の径方向の寸法が小型化出来る。
（１０）請求項１０の発明によれば、光軸方向の移動スペースを確保する必要がないので、請求項８の発明による効果に加え、中間光学系の光軸方向の寸法が小型化出来る。
（１１）請求項１１の発明によれば、撮影時間が短くなる。又撮影操作が少なくなるので、使い勝手が良くなる。
（１２） 請求項１２の発明によれば、撮影ユニットの奥行寸法が小さくなり、且つ大きなファインダ像が観察でき使いやすい。又撮影範囲とファインダ視野が一致する。更にのぞき込むタイプのファインダとなるので、太陽光などの有害光を遮蔽（カット）することができる見やすいファインダとなる。又接眼レンズが不要なので、光学系が簡素化出来る。
（１３）請求項１３の発明によれば、撮像ユニットの奥行寸法が小さくなる。
（１４）請求項１４の発明によれば、自動的にミラーアップを禁止するので、誤操作がなくなり使いやすくなる。又自動的に表示するので、操作が少なくなり撮影上の使い勝手が良くなる。
（１５）請求項１５の発明によれば、撮像ユニットの奥行寸法が小さくなる。
【図面の簡単な説明】
【図１】本発明のカメラシステム第１の実施例の概略図
【図２】上記第１の実施例で用いる光学系の構成を示す図
【図３】上記第１の実施例の変形例の概略図
【図４】上記第１の実施例の他の変形例の概略図
【図５】本発明の第２の実施例の光学系の構成を示す図
【図６】本発明の第２の実施例の他の光学系の構成を示す図
【図７】本発明の第３の実施例の構成を示す図
【図８】本発明の第３の実施例の他の構成を示す図
【図９】本発明の第３の実施例の他の構成を示す図
【図１０】本発明の第４の実施例の光学系の構成を示す図
【図１１】本発明の第５の実施例の概略図
【図１２】上記第４、第５の実施例における焦点距離切換のタイミングを示す図
【図１３】本発明の第６の実施例の光学系の構成を示す図
【図１４】本発明の第７の実施例の他の光学系の構成を示す図
【図１５】本発明の第８の実施例の概略図
【図１６】上記第８の実施例で用いられる光学系を示す図
【図１７】上記第８の実施例の制御のための回路図
【図１８】上記制御のフローチャート
【図１９】本発明の第９の実施例の概略図
【図２０】従来のカメラシステムの概略図
【図２１】従来のカメラシステムで用いる光学系の構成を示す図
【符号の説明】
１ 撮影レンズユニット、２ カメラ本体、３ ファインダー、
４ 撮像ユニット、５ 中間レンズユニット、ＬＳ 撮影光学系、
ＬＳ１ 第１の中間光学系、ＬＳ２ 第２の中間光学系[0001]
[Industrial application fields]
The present invention relates to an optical system that re-images subject light, and more particularly to a camera system including an optical system that converts a screen size while maintaining the angle of view of a photographing optical system, and an intermediate lens unit and an imaging unit used therefor Is.
[0002]
[Prior art]
In recent years, small CCDs [for example, 1/3 inch CCD (3.2 ×, for example, 3 × 4.3 mm)] has been proposed.
[0003]
This camera system has the advantage that the existing camera body and imaging optical system (interchangeable lens, interchangeable lens aperture, shutter function, viewfinder, etc.) can be used.
[0004]
However, the re-imaging optical system of the camera system described above needs to reduce only the screen size while maintaining the angle of view in order to match the screen sizes of the finder image and the captured image.
[0005]
In addition, as a typical colorization method in a camera system using a CCD, (1) a method in which on-chip color filters are arranged on the surface of the CCD, and (2) a monochrome CCD is used, and the RGB filters on the surface are replaced in a time-sharing manner. And (3) a system in which a monochrome CCD is arranged on a color separation dichroic prism. For this reason, the back focus length required for the optical system differs depending on the colorization method.
[0006]
As described above, in order to realize the above-described color camera system, only the screen size is reduced while maintaining the angle of view, the back focus has a practical length, and the imaging performance is excellent. A re-imaging optical system is required. As a conventional example based on this requirement, a camera system disclosed in Japanese Patent Laid-Open No. 7-27969 is known.
[0007]
FIG. 20 is a schematic diagram of a conventional camera system. In the figure, reference numeral 1 denotes a photographing lens unit or a taking lens, which has an action of guiding light from a subject to an image forming surface. The photographing lens unit 1 has a lens mount portion 1 a for attaching to the camera body 2, and this is attached to the mount 2 a of the camera body 2. The camera body 2 is provided with a quick return mirror M1. Reference numeral 3 denotes a finder system, and 4 denotes an image pickup unit in which a re-imaging lens 5 and a color separation prism 6 are housed. The imaging unit 4 has a connection portion 4 a that is connected to the connection portion 2 b of the camera body 2, whereby the imaging unit 4 is connected to the camera body 2.
[0008]
When the camera system is not in the shooting state, light from the subject is reflected by the quick return mirror M1 by the shooting optical system (taking lens) provided in the shooting lens unit 1 and directed to the viewfinder 3 by the viewfinder. Observed. At the time of shooting, the quick return mirror M1 is flipped up to form an image on the imaging plane, and the screen size is changed by the re-imaging lens 5 without changing the angle of view.
[0009]
As an optical system used in the conventional camera system as described above, an optical system having a structure as shown in FIG. 21 is conceivable, and lens data thereof is as follows. r ₀ = ∞ d ₀ = ∞
r ₁ = ∞ d ₁ = 10.0000
r ₂ = ∞ d ₂ = 127.2900
r _Three = -1209.0909 d _Three = 11.0000 n ₁ = 1.77250 ν ₁ = 49.60
r _Four = -121.7733 d _Four = 0.2000
r _Five = 147.3340 d _Five = 10.5000 n ₂ = 1.77250 ν ₂ = 49.60
r ₆ = 2599.3181 d ₆ = 0.2000
r ₇ = 68.1839 d ₇ = 10.5000 n _Three = 1.77250 ν _Three = 49.60
r ₈ = 108.3374 d ₈ = 80.1551
r ₉ = -37.1082 d ₉ = 2.2000 n _Four = 1.48749 ν _Four = 70.21
r _Ten = 50.6969 d _Ten = 10.1323
r ₁₁ = -260.9079 d ₁₁ = 10.5324 n _Five = 1.80610 ν _Five = 40.95
r ₁₂ = -36.8456 d ₁₂ = 1.0149
r ₁₃ = 56.2228 d ₁₃ = 7.3147 n ₆ = 1.80610 ν ₆ = 40.95
r ₁₄ = 650.8019 d ₁₄ = 3.6249
r ₁₅ = -40.4215 d ₁₅ = 2.1550 n ₇ = 1.51633 ν ₇ = 64.15
r ₁₆ = 49.9415 d ₁₆ = 7.2291
r ₁₇ = ∞ (aperture) d ₁₇ = 6.9497
r ₁₈ = -27.3188 d ₁₈ = 1.7678 n ₈ = 1.69895 ν ₈ = 30.12
r ₁₉ = 260.8560 d ₁₉ = 0.5000
r ₂₀ = 311.6856 d ₂₀ = 9.8730 n ₉ = 1.80610 ν ₉ = 40.95
r _{twenty one} = -37.1814d _{twenty one} = 2.2554
r _{twenty two} = -37.5763 d _{twenty two} = 2.6280 n _Ten = 1.80518 ν _Ten = 25.43
r _{twenty three} = 681.0731 d _{twenty three} = 16.0533 n ₁₁ = 1.62299 ν ₁₁ = 58.15
r _{twenty four} = -42.8890 d _{twenty four} = 0.2276
r _{twenty five} = -627.1196 d _{twenty five} = 5.6021 n ₁₂ = 1.77250 ν ₁₂ = 49.60
r ₂₆ = -75.4328 d ₂₆ = 0.2449
r ₂₇ = 147.9235 d ₂₇ = 5.9990 n ₁₃ = 1.77250 ν ₁₃ = 49.60
r ₂₈ = -191.2527 d ₂₈ = 0.2000
r ₂₉ = 61.4310 d ₂₉ = 7.1998 n ₁₄ = 1.71999 ν ₁₄ = 50.25
r ₃₀ = 3454.0861 d ₃₀ = 2.0000 n ₁₅ = 1.84666 ν ₁₅ = 23.78
r ₃₁ = 136.2789 d ₃₁ = 3.6505
r ₃₂ = ∞ d ₃₂ = 5.0000 n ₁₆ = 1.51633 ν ₁₆ = 64.15
r ₃₃ = ∞ d ₃₃ = 1.000
r ₃₄ = ∞ d ₃₄ = 55.0000 n ₁₇ = 1.58267 ν ₁₇ = 46.39
r ₃₅ = ∞ d ₃₅ = 4.9962
r ₃₆ = ∞ (image plane)
Where r ₁ , R ₂ , ... are the radii of curvature of each surface, d ₁ , D ₂ , ... are the thickness of each lens and the lens interval, n ₁ , N ₂ , ... are the refractive indices of each lens, ν ₁ , Ν ₂ , ... are Abbe numbers of each lens. R ₀ Is the object (subject) surface, d ₀ Is the object distance, r ₁ Is a photographing optical system (taking lens) LS, which is represented by a plane for convenience, but is actually an optical system composed of a large number of lenses, r ₂ Indicates the aperture of the photographing optical system.
[0010]
The unit of length of r, d, etc. in this data and lens data of the optical system shown later is mm.
In the above optical system, the range of 69.5 mm × 69.5 mm imaged by the taking lens is set so as to re-image on the image sensor of 15 mm × 15 mm. The photographing lens was set with a focal length of 140 mm. In the examples shown later, the same photographing lens was applied.
[0011]
In the drawing, LS is the above-described photographing optical system (taking lens) and is schematically shown together with the stop S1. The lens system described behind (image side) of the photographing optical system LS is an optical system that maintains the angle of view of the image formed by the photographing lens and converts the screen size, that is, the re-imaging lens 5.
[0012]
In this re-imaging lens _Three ~ R ₈ Is field lens FL, r ₉ ~ R ₃₁ Is a relay lens RL. R ₃₂ ~ R ₃₃ Is an optical element such as quartz, r ₃₄ ~ R ₃₅ Is a color separation prism.
[0013]
In this optical system, an image I1 is formed in the field lens FL in the re-imaging lens 5 by the photographing optical system LS, and an image I2 is further formed on the image sensor. The F number on the re-imaging lens side of this optical system is 1.4.
[0014]
[Problems to be solved by the invention]
In the camera system described above, when trying to actually construct a re-imaging optical system that reduces the screen size while maintaining the angle of view, has a practically long back focus, and has excellent imaging performance, A re-imaging lens must be disposed on the optical axis between the photographing lens unit and the CCD, and the depth of the imaging unit is inevitably increased. Further, when the color separation dichroic prism is used by the colorization method, the depth dimension of the imaging unit is further increased.
[0015]
In the conventional example shown in FIG. 20 using the above-described 6 × 7 medium format camera, the depth dimension is as shown in the data from the surface on which the film, which is the imaging position by the photographing optical system, to the image receiving surface of the CCD. When the length is L, L = 283 mm.
[0016]
Further, the depth of the imaging unit is further increased depending on the brightness of the optical system used, the size of the CCD, and the magnification of the re-imaging lens.
[0017]
When the depth dimension of the image pickup unit is increased in this way, the balance of the weight of the entire apparatus becomes worse, the viewfinder becomes difficult to see, and the merchantability itself that hinders photographing itself becomes a problem.
[0018]
The present invention provides a camera system having a re-imaging optical system in which the depth dimension of an imaging unit is shortened as much as possible and good imaging can be performed.
[0019]
The present invention provides an intermediate lens unit that is inserted between a photographing lens unit and a camera body in the camera system.
[0020]
Furthermore, the present invention provides an imaging unit suitable for the camera system.
[0021]
[Means for Solving the Problems]
The camera system of the present invention includes an imaging optical system that forms an image of subject light at a predetermined position in the camera body, and includes a first lens mount unit that can be connected to a camera mount unit provided in the camera body. A lens unit;
A first intermediate optical system that is inserted between the photographic lens unit and the camera body and that enters the subject light emitted from the photographic optical system in the photographic lens unit and emits it toward the camera body. An intermediate lens unit comprising: a second lens mount portion that can be connected to the first lens mount portion of the photographic lens unit; and a third lens mount portion that can be connected to the camera mount portion of the camera body;
An imaging unit having an imaging unit connection portion connected to a camera body connection portion provided on the opposite side of the camera mount portion of the camera body,
When the imaging unit connects the intermediate lens unit to which the imaging lens unit is connected to the camera body, subject light emitted from the imaging optical system in the imaging lens unit is the first intermediate optical in the intermediate lens unit. A second intermediate optical system for re-imaging with the system;
And an imaging means for converting the received object light into an electrical signal and outputting it at the re-imaging position by the second intermediate optical system.
[0022]
That is, the camera system of the present invention uses a camera body having a photographing optical system such as a conventionally known 35 mm camera, 6 × 7 medium format camera, etc., and includes a relay lens and an imaging means in the camera body. When the image of the subject light formed by the imaging optical system on the film surface in the camera body is re-imaged on the image receiving surface of the imaging means by the relay lens, the imaging optical system is An intermediate lens unit having a first intermediate optical system is inserted between the provided photographic lens unit and the camera body, and the magnification of the image by the photographic optical system is changed (reduced) to the first intermediate optical system. ), The second intermediate optical system, which is a relay lens arranged in the image pickup unit, is imaged by the combined optical system of the image pickup optical system and the first intermediate optical system. light This image is re-imaged on the imaging surface of the imaging means, thereby shortening the depth of the imaging unit.
[0023]
Furthermore, the present invention provides a camera system in which the intermediate lens unit is inserted between the photographing lens unit and the camera body as described above, and the image pickup unit is mounted on the opposite side of the camera body from the intermediate lens unit. The present invention relates to an intermediate lens unit characterized by having a first intermediate optical system, and by using this intermediate lens unit, the depth of the imaging unit can be shortened. It is said.
[0024]
The present invention also provides a camera system in which an intermediate lens unit is inserted between the photographing lens unit and the camera body as described above, and an image pickup unit is mounted on the opposite side of the camera body from the intermediate lens unit. The present invention relates to an imaging unit including a second intermediate optical system, in which the second intermediate optical system emits the photographic optical system of the photographic lens unit together with the first intermediate optical system included in the intermediate lens unit. Is reduced and formed on the light receiving surface of the imaging means, and the length in the depth direction is shortened.
[0025]
【Example】
Next, an embodiment of the camera system of the present invention will be described with reference to the drawings.
[0026]
FIG. 1 is a schematic view of a first embodiment of the camera system of the present invention. In the figure, 1 is a photographic lens unit having a photographic optical system (taking lens) inside, 1a is a first lens mount portion provided in the photographic lens unit, 2 is a camera body and has a quick return mirror M1 inside. doing. The camera body 2 is provided with a camera mount portion 2a and a camera body connection portion 2b. Reference numeral 3 denotes a finder, and 4 denotes an image pickup unit having a second intermediate optical system LS2 (relay lens RL) and a color separation prism P1 therein, and has an image pickup unit connection portion 4a. These have substantially the same configuration as the conventional camera system shown in FIG.
[0027]
In the present invention, the intermediate lens unit 10 including the first intermediate optical system is provided between the photographing lens unit 1 and the camera body 2, and the second intermediate optical provided inside the imaging unit 4. The system differs from the conventional camera system. The intermediate lens unit 10 has a second lens mount portion 10 a for connecting to the photographing lens unit 1 and a third lens mount portion 10 b for connecting to the camera body 2.
[0028]
The intermediate lens unit 10 receives subject light emitted from the photographing optical system by a first intermediate optical system included therein and emits the light toward the camera body.
[0029]
The imaging unit 4 includes a second intermediate optical system and a three-color separation prism, and subject light emitted from the first intermediate optical system of the intermediate lens unit 10 to the camera body by the second intermediate optical system. Is re-imaged on the imaging surface of the imaging means (imaging device).
[0030]
Next, the optical system used in the first embodiment of the present invention will be described.
[0031]
The optical system of the first embodiment is configured as shown in FIG. 2, LS is a photographing optical system, LS1 is a first intermediate optical system, LS2 is a second intermediate optical system (relay lens RL), The first intermediate optical system LS1 and the second intermediate optical system constitute an imaging optical system (re-imaging optical system). Note that S2 represents a stop in the second intermediate optical system. P1 is a color separation prism, and P2 is an optical element such as a crystal, a λ / 4 plate, or an infrared cut filter.
[0032]
Like this optical system, by inserting the intermediate lens unit 10 between the photographic lens unit 1 and the camera body 2, the re-imaging lens is inserted into the first intermediate optical system LS1 arranged in the intermediate lens unit 10. A part of the functions can be provided. As a result, the distance from the position where the normal film, which is the imaging position I1 by the photographing optical system LS, is placed to the imaging surface I2 is shortened.
[0033]
The main role of the first intermediate optical system LS1 is that the image formed by the photographing optical system LS is reduced and re-imaged, and the off-axis principal ray exiting the photographing optical system LS as a field lens is relay lens. The point is to lead to the system RL.
[0034]
The main role of the second intermediate optical system LS2 (relay lens system RL) is to re-image the image formed by the photographic optical system LS on the light receiving surface of the image sensor and maintain the angle of view. This is a function of changing the magnification for converting the size.
[0035]
The lens data of the optical system used in the first embodiment shown in FIG. 2 is as follows.
r ₀ = ∞ d ₀ = ∞
r ₁ = ∞ d ₁ = 10.0000
r ₂ = ∞ (aperture) d ₂ = 46.0141
r _Three = -85.6434 d _Three = 7.1570 n ₁ = 1.77250 ν ₁ = 49.60
r _Four = -57.3801 d _Four = 3.0473
r _Five = 339.1009 d _Five = 5.7618 n ₂ = 1.77250 ν ₂ = 49.60
r ₆ = -169.5222 d ₆ = 2.9063
r ₇ = 55.0218 d ₇ = 10.0561 n _Three = 1.77250 ν _Three = 49.60
r ₈ = 454.8651 d ₈ = 2.9491 n _Four = 1.69895 ν _Four = 30.12
r ₉ = 101.3179 d ₉ = 102.001
r _Ten = ∞ d _Ten = -4.4947
r ₁₁ = 608.6554 d ₁₁ = 8.0000 n _Five = 1.77250 ν _Five = 49.60
r ₁₂ = -74.8003 d ₁₂ = 10.4046
r ₁₃ = 77.8124 d ₁₃ = 8.2585 n ₆ = 1.83400 ν ₆ = 37.17
r ₁₄ = 1623.7314 d ₁₄ = 0.9022
r ₁₅ = 26.8797 d ₁₅ = 10.4138 n ₇ = 1.83481 ν ₇ = 42.72
r ₁₆ = 21.6837 d ₁₆ = 4.4719
r ₁₇ = -319.0580 d ₁₇ = 2.4031 n ₈ = 1.64769 ν ₈ = 33.80
r ₁₈ = 24.3687 d ₁₈ = 6.2439
r ₁₉ = ∞ (aperture) d ₁₉ = 5.8207
r ₂₀ = -18.0536 d ₂₀ = 1.7678 n ₉ = 1.69895 ν ₉ = 30.12
r _{twenty one} = 124.5073 d _{twenty one} = 11.3669 n _Ten = 1.83481 ν _Ten = 42.72
r _{twenty two} = -23.9453 d _{twenty two} = 2.6938
r _{twenty three} = -22.2900 d _{twenty three} = 2.4430 n ₁₁ = 1.69895 ν ₁₁ = 30.12
r _{twenty four} = 1215.9259 d _{twenty four} = 11.9520 n ₁₂ = 1.83481 ν ₁₂ = 42.72
r _{twenty five} = -40.2427 d _{twenty five} = 0.2000
r ₂₆ = -1807.4841 d ₂₆ = 7.0942 n ₁₃ = 1.56907 ν ₁₃ = 71.30
r ₂₇ = -70.7088 d ₂₇ = 0.2449
r ₂₈ = 120.5998 d ₂₈ = 6.3741 n ₁₄ = 1.56907 ν ₁₄ = 71.30
r ₂₉ = -281.2388 d ₂₉ = 0.2000
r ₃₀ = 58.9420 d ₃₀ = 9.4834 n ₁₅ = 1.77250 ν ₁₅ = 49.60
r ₃₁ = -243.2558 d ₃₁ = 1.8400 n ₁₆ = 1.69895 ν ₁₆ = 30.12
r ₃₂ = 101.3305 d ₃₂ = 3.9972
r ₃₃ = ∞ d ₃₃ = 5.0000 n ₁₇ = 1.51633 ν ₁₇ = 64.15
r ₃₄ = ∞ d ₃₄ = 1.000
r ₃₅ = ∞ d ₃₅ = 55.0000 n ₁₈ = 1.58267 ν ₁₈ = 46.39
r ₃₆ = ∞ d ₃₆ = 5.0037
r ₃₇ = ∞ (image plane)
R in this data ₁ , R ₂ , ..., d ₁ , D ₂ ... Others are the same as the data of the conventional optical system.
[0036]
In the data, r ₀ Is the object plane, r ₁ Is the photographic optical system LS, r ₂ Is the aperture S2, r _Three ~ R ₉ Is the first intermediate optical system LS1, r _Ten Is an imaging position by the photographing optical system LS (film position in the camera body at the imaging position when the first intermediate optical system is not used) I1, r ₁₁ ~ R ₃₂ Is the second intermediate optical system LS2, r ₃₃ ~ R ₃₄ Is an optical element P2, r such as crystal or infrared cut filter ₃₅ ~ R ₃₆ Is the three-color separation filter P1, r ₃₇ Is the imaging surface I2.
[0037]
With this data, d ₉ The camera main body 2 is arranged in this part, the intermediate lens unit 10 is arranged in front of it, and the imaging unit 4 is arranged in the rear.
[0038]
In the first embodiment, the intermediate lens unit 10 is disposed between the photographing lens unit 1 and the camera body 2, so that the function of the imaging lens is added to the first intermediate optical system LS1 included in the intermediate lens unit 10. As a result, the distance from the surface I1 where the normal film surface of the photographing optical system LS is located to the photographing surface I2 is 178 mm, and the depth of the imaging unit 4 is shortened. The image plane I1 (r _Ten ) Is the first surface (r) of the second intermediate optical system LS2. ₁₁ ) Located closer to the imaging surface side (because it exists in the lens, r _Ten To r ₁₁ Interval d _Ten The value of is negative and d _Ten Is the thickness r on the optical axis of the leading lens of the second intermediate optical system ₁₁ And r ₁₂ Is the interval between. In this embodiment, the design conditions such as the re-imaging magnification and the focal length of the photographing lens are the same as those of the optical system shown in FIG.
[0039]
The first intermediate optical system of this embodiment plays a role of reducing the image by the photographing optical system and guides the off-axis principal ray emitted from the photographing optical system as a field lens to the relay lens system (second intermediate optical system). Have a role.
[0040]
The second intermediate optical system has a role of re-imaging an image formed by the photographing optical system and a role of changing the magnification in order to change the screen size while maintaining the angle of view.
[0041]
According to the first embodiment, as described above, the depth of the image pickup unit is small, the first intermediate optical system is also small, and the camera system can be made compact.
[0042]
3 and 4 show modifications of the first embodiment, and FIG. 3 shows a color separation prism P in the camera system of the embodiment shown in FIG. ₁ This is an example that does not use. FIG. 4 shows a color separation prism P behind the imaging lens LS2 as in FIG. ₁ This is an example in which an RGB filter F is attached to the object side of the photographing unit 1 without using the above. Other configurations are substantially the same as those of the camera system shown in FIG.
[0043]
Next, a means for correcting the exit pupil position of the subject light incident from the photographing optical system, which is one of the features of the present invention, will be described based on the first embodiment.
[0044]
As described above, the intermediate optical system LS1 has an action of reducing an image and an action of guiding an off-axis principal ray to the second intermediate optical system LS2 (relay lens RL). In the absence of the first intermediate optical system, the off-axis principal ray that passes through the imaging optical system LS and exits from the optical axis proceeds gradually away from the optical axis and does not enter the second intermediate optical system (relay lens RL). The first intermediate optical system LS1 also has an action of refracting the off-axis principal ray so as to be directed toward the stop S2 of the second intermediate optical system LS2 (relay lens RL).
[0045]
However, the action of refracting the off-axis principal ray by the first intermediate optical system LS1 may differ depending on the type of the photographing optical system. That is, the angle formed by the optical axis of the off-axis principal ray emitted from the photographing optical system may differ depending on the kind of the photographing optical system, and therefore the refraction angle of the off-axis principal ray by the first intermediate optical system LS1 is also used. It is necessary to make it different depending on the type of photographing optical system. In other words, the angle of the off-axis principal ray emitted from the photographing optical system is equivalent to the exit pupil position of the off-axis photographing optical system, and thus the exit pupil position differs depending on the type of the photographing optical system. .
[0046]
The exit pupil position of the photographic optical system is obtained by measuring the position where the off-axis principal ray intersects the optical axis with reference to the position where the optical system is located. For example, when measuring with respect to the film surface that is the imaging position of the imaging optical system, if the distance from this reference position to the position where the off-axis principal ray intersects the optical axis is called the exit pupil position, this exit pupil position The angle between the off-axis principal ray and the optical axis differs depending on whether the distance is near or far. Specifically, the farther the exit pupil position is, the smaller the off-axis principal ray angle becomes.
[0047]
The interchangeable photographic optical system has various exit pupil positions depending on the type, and the value is a value unique to the photographic optical system.
[0048]
When such various photographic optical systems are attached to the camera system and used for replacement, with respect to a certain photographic optical system, the off-axis principal ray smoothly passes through the field lens FL and reaches the relay lens RL. When another imaging optical system having a different exit pupil is mounted, the off-axis chief ray that has passed through the field lens FL (first intermediate optical system) enters the relay lens RL (second intermediate optical system). Does not reach, and as a result, the periphery of the screen becomes dark, and in the extreme case, the field of view around the screen is taken.
[0049]
In the present invention, even when an imaging optical system with a different exit pupil position is used while waiting for the first intermediate optical system to correct the deviation of the imaging optical system, the deviation of the exit pupil position is corrected and the periphery of the screen becomes dark. I am trying not to be out of sight.
[0050]
Next, specific means for correcting the exit pupil position by the intermediate optical system will be described.
[0051]
FIG. 5 shows an optical system having means for correcting the exit pupil position according to the second embodiment of the present invention, and (A) and (B) relate to the photographing optical system LS at different exit pupil positions. It is shown in In this embodiment, the first intermediate optical system is composed of two lens groups G1 and G2, and another photographic optical system is used from the state shown in (A) when a certain photographic optical system is used. Interval D to the state shown in (B) ₁ , D ₂ , D _Three (Distance D from the exit pupil of the photographing optical system to the intermediate optical system D ₁ The distance D between the lens group G1 and the lens group G2 of the first intermediate optical system ₂ , The distance D from the intermediate optical system to the imaging position by the intermediate optical system _Three ) To adjust.
[0052]
The data of this optical system is as follows.

The reference position is the imaging position (r of the first intermediate optical system. ₁₇ ).
As is apparent from this data, the interval D ₁ , D ₂ , D _Three It can be seen that the exit pupil position can be adjusted in the state (A) and the state (B) with reference to the imaging position of the first intermediate optical system by changing.
[0053]
FIG. 6 shows another example of the optical system of the second embodiment of the present invention. Similarly, FIG. 6A shows the state of the first intermediate optical system when a certain photographing optical system is used, and FIG. 6B shows another photographing optical system different from the photographing optical system in FIG. It is a figure which shows the state of the 1st intermediate optical system when used.
[0054]
The lens data of the optical system shown in this figure is as follows.

The reference position is the imaging position (r of the first intermediate optical system. ₁₈ ).
The above optical system is also D in the data ₁ , D ₂ , D _Three The exit pupil position can be corrected corresponding to the photographic optical system to be used by changing.
[0055]
Next, an optical system provided with another example of specific means relating to the correction of the exit pupil position according to the third embodiment of the present invention will be described. In this embodiment, the exit pupil position is corrected by detachably placing a lens near the imaging position of the intermediate optical system, or by placing a lens having a different power in a replaceable manner.
[0056]
FIG. 7 is a schematic diagram showing the correction means, wherein LS is a photographing optical system, LS1 is a first intermediate optical system, and CL is an exit pupil position correcting lens. Thus, by arranging the correction lens CL near the imaging position of the first intermediate optical system, the off-axis principal ray can be bent, and the off-axis principal ray can be turned into the second intermediate optical system LS2 (relay lens). RL). That is, the correction of the exit pupil position is enabled by inserting / removing the correction lens CL in the first intermediate optical system in accordance with replacement of the photographing optical system.
[0057]
The exit pupil position correcting means of the third embodiment shown in FIG. 7 performs two-stage correction, but multi-stage correction is possible by using a plurality of correction lenses having different powers.
[0058]
FIG. 8 shows that a large number of correction lenses can be exchanged in the third embodiment. On the disk as shown in FIG. 8B near the image forming position of the first intermediate optical system LS1 shown in FIG. The correction lenses CL1, CL2, CL3, and CL4 having different powers are arranged on the lens, and the disk is rotated, so that the lens CL1, CL2,... Can be corrected. That is, the correction lens is switched by the turret method.
[0059]
FIG. 9 is a schematic view showing still another specific means for correcting the exit pupil position. In FIG. 9, a lens CL5 is made of a transparent elastic body that can mechanically change the refractive power in the vicinity of the image forming position of the first intermediate optical system, for example, silicon rubber as shown in Japanese Patent Laid-Open No. 62-163401. The lens shape is changed by applying a force to change the refractive power of the lens to switch the exit pupil position, which is the angle of the off-axis principal ray.
[0060]
The exit pupil position can be similarly switched by using a liquid lens as described in JP-A-4-34512 instead of the lens made of the transparent elastic body and changing its refractive power. .
[0061]
Alternatively, the refractive power can be similarly changed by using a liquid crystal lens capable of electrically changing the refractive power as the correction lens. Specifically, the exit pupil position can be corrected by changing the refractive index of the liquid crystal using a liquid crystal lens described in JP-A-4-345124.
[0062]
Next, the influence on the finder optical system when the first intermediate optical system LS1 is inserted will be described.
[0063]
As described above, when the first intermediate optical system LS1 is inserted between the photographing lens unit 1 and the camera body 2, the magnification of the image changes. Specifically, the first intermediate optical system functions to reduce the magnification. By mounting the intermediate lens unit including the first intermediate optical system LS1 in this way, the screen size is converted on the imaging side. On the other hand, on the viewing side (finder side), the angle of view and magnification change. That is, in the case of the conventional optical system shown in FIG. 20 that does not use the first intermediate optical system having the function of reducing magnification, the subject light is imaged on the film surface on the imaging side by the photographing optical system and on the film surface on the viewfinder side. In the present invention, an optical system composed of a photographic optical system LS and a first intermediate optical system in order to insert the first intermediate optical system having the function of reducing the magnification. Has a focal length different from the focal length of the original photographing optical system alone. Therefore, on the finder side, the photographing range and the finder field of view are different before and after the first intermediate optical system is inserted, and the focal length is shifted. .
[0064]
The present invention is also characterized in that there is provided means for eliminating the influence on the finder side when the first intermediate optical system is inserted.
Next, means for eliminating the influence on the finder system will be described based on the fourth embodiment.
[0065]
FIG. 10 is a diagram showing the configuration of the first intermediate optical system of the fourth embodiment of the present invention in which the influence on the finder system is removed. FIG. 10A shows the quick return mirror (reflection optical system) lifted up. (B) is a configuration when the quick return mirror is lowered and observed with a finder (when framing). As shown in this figure, the first intermediate optical system LS1 is formed of a lens group G1 and a lens group G2, and these lens groups G1 and G2 are moved so that the distance from the exit pupil position of the photographic optical system to the lens group G1. D ₁ , The distance D between the lens group G1 and the lens group G2. ₂ The distance D from the lens group G2 to the image position by the first intermediate optical system (image formation position by the combined optical system of the photographing optical system and the first intermediate optical system) _Three Thus, the focal length of the first intermediate optical system is changed. That is, in the state of FIG. 10A, the combined focal length of the photographing optical system and the first intermediate optical system is adjusted at the time of imaging, and in the state of FIG. 10B, the focal length of the photographing optical system is not changed. Like that.
[0066]
Here, data of the optical system of the fourth embodiment shown in FIG. 10 is shown.

In this example, the value as shown in the above data is D ₁ , D ₂ , D _Three The focal length of the combination of the photographic optical system and the first intermediate optical system is 56 mm at the time of imaging [FIG. 10A] and 140 mm at the time of observation [FIG. 10B]. Note that the focal length of only the photographing optical system is assumed to be 140 mm. Thus, in the fourth embodiment, on the finder side, the combined focal length of the photographic optical system and the first intermediate optical system is the same value as the focal length of only the photographic optical system, and the combined during imaging The focal length of the lens becomes as small as 56 mm, a reduction magnification, and is reduced to about 0.4 times.
[0067]
FIGS. 11A and 11B show a fifth embodiment of the present invention, which is another embodiment that can be adjusted so that good observation can be performed with the viewfinder even when the first intermediate optical system is inserted. It is the schematic which shows an example.
[0068]
In this embodiment, the first intermediate optical system can be inserted and removed, and the above adjustment is performed.
[0069]
In FIG. 11, LS is a photographing optical system, LS1 is a first intermediate optical system, LS2 is a second intermediate optical system (relay lens), and the first intermediate optical system LS1 is inserted at the time of imaging (A). The photographic optical system LS, the first intermediate optical system LS1, and the second intermediate optical system LS2 form subject light on the image sensor. At this time, the quick return mirror (reflection optical system) M1 is lifted up. (B) is at the time of observation, and the first intermediate optical system is removed from the optical path, and the quick return mirror M1 is disposed in the optical path, and observation with the finder is performed. In (B), since the first intermediate optical system LS1 is removed from the optical path, the focal length of the optical system is the focal length of the photographing optical system itself.
[0070]
FIG. 12 is a diagram showing the switching timing of the focal length in the fourth and fifth embodiments. In this figure, (a) is a release and a1 is on, (b) is when the lens shutter is opened and closed and b1 is closed, b2 is opened, (c) is the mirror position, c1 is up, and c2 is down. (D) is the switching of the focal length, d1 is during imaging, and d2 is during observation.
[0071]
In FIG. 12, before the release, the shutter (b) is open at b2, the mirror (c) is down at c2, the focal length (d) is d2 at the time of observation, and the subject light is It reaches the finder side and observation with the finder is possible. In this state, t ₁ If release (a) is turned on (a1) at time t, then t ₂ The shutter closes at (b1) and then t _Three Mirror (c) is c ₂ To c ₁ The focal length (d) is changed from d2 to d1, and the focal length at the time of imaging is changed. T _Four In FIG. 5, the shutter (b) is opened by b1 to b2, and the subject light advances to the imaging side and is imaged. T after imaging _Five The shutter is closed at t ₆ The mirror goes down and the focal length changes to the viewing side, t ₇ The shutter opens and returns to the original state.
[0072]
When the intermediate lens unit is inserted behind the photographic lens unit and the first intermediate optical system is arranged behind the photographic optical system as in the camera system of the present invention, the photographic optical system is provided by the first intermediate optical system. Is reduced and formed in the optical path. When observing on the finder side in such an optical system, a small image is also formed on the finder side, so that it is difficult to observe with an ordinary finder.
[0073]
In order to solve this problem, in the present invention, a reflection optical system for switching the optical path to the viewfinder side or the image pickup surface side in the image pickup unit is provided, and the reflected viewfinder side optical system is replaced with the first intermediate optical system. The reduced image is enlarged and re-imaged.
[0074]
FIG. 13 is a view showing an optical system of a sixth embodiment for enlarging the image on the finder side. In FIG. 13, LS is a photographing optical system, S1 is its exit pupil, LS1 is a first intermediate optical system, M1 and M2 are reflecting mirrors (reflecting optical systems) for directing the optical path toward the viewfinder, LS3 is a viewfinder optical system, I3 is an enlarged image formed by the finder optical system LS3, and forms an enlarged viewfinder that is easy to observe.
[0075]
The data of the optical system of the sixth embodiment is as follows.
r ₀ = ∞ d ₀ = ∞
r ₁ = ∞ d ₁ = 10.0000
r ₂ = ∞ d ₂ = 46.0141
r _Three = -85.6434 d _Three = 7.1570 n ₁ = 1.77520 ν ₁ = 49.60
r _Four = -57.3801 d _Four = 3.0473
r _Five = 339.1009 d _Five = 5.7618 n ₂ = 1.77250 ν ₂ = 49.60
r ₆ = -169.5222 d ₆ = 2.9063
r ₇ = 55.0218 d ₇ = 10.0561 n _Three = 1.77250 ν _Three = 49.60
r ₈ = 454.8651 d ₈ = 2.9491 n _Four = 1.69895 ν _Four = 30.12
r ₉ = 101.3179 d ₉ = 52.0001
r _Ten = ∞ d _Ten = -50.5019
r ₁₁ = -89.3557 d ₁₁ = -8.0973 n _Five = 1.83400 ν _Five = 37.17
r ₁₂ = 155.6836 d ₁₂ = -0.2000
r ₁₃ = -24.1732 d ₁₃ = -13.3283 n ₆ = 1.77250 ν ₆ = 49.60
r ₁₄ = 233.3051 d ₁₄ = -3.1675 n ₇ = 1.69895 ν ₇ = 30.12
r ₁₅ = -13.4856 d ₁₅ = -17.0484
r ₁₆ = 13.4337 d ₁₆ = -3.0292 n ₈ = 1.63980 ν ₈ = 34.48
r ₁₇ = 816.1918 d ₁₇ = -9.3085 n ₉ = 1.63854 ν ₉ = 55.38
r ₁₈ = 23.1101 d ₁₈ = -1.2872
r ₁₉ = 67.1623 d ₁₉ = -4.4975 n _Ten = 1.56907 ν _Ten = 71.30
r ₂₀ = 28.4103 d ₂₀ = -25.0000
r _{twenty one} = ∞ d _{twenty one} = 178.9927
r _{twenty two} = ∞
In the above data _Ten Is the reflector M ₁ , R _{twenty one} Is the reflector M ₂ , R _{twenty two} Is an imaging position by the finder optical system. The imaging magnification of the first intermediate optical system LS1 is 0.40, and the imaging magnification of the finder optical system LS3 is -2.5.
[0076]
Thus, the image reduced by the first intermediate optical system can be enlarged and observed by the finder optical system.
[0077]
FIG. 14 is a diagram showing another finder optical system. In the figure, the optical system up to the quick return mirror (reflecting mirror M1) is the same as the optical system shown in FIG. The optical system on the finder side includes an optical system LS3 and an eyepiece optical system EL including lens groups G1 and G2. M2 is a reflector as in FIG.
[0078]
In the optical system of this embodiment, the light emitted from the first intermediate optical system LS1 is reflected by the reflecting mirror M1 and re-imaged near the lens group G1 of the eyepiece optical system EL at the same magnification by the optical system LS3. . Further, the image is magnified and observed by the eyepiece optical system EL.
[0079]
The data of this example is as follows.
r ₀ = ∞ d ₀ = ∞
r ₁ = ∞ d ₁ = 10.0000
r ₂ = ∞ (aperture) d ₂ = 46.0141
r _Three = -85.6434 d _Three = 7.1570 n ₁ = 1.77520 ν ₁ = 49.60
r _Four = -57.3801 d _Four = 3.0473
r _Five = 339.1009 d _Five = 5.7618 n ₂ = 1.77250 ν ₂ = 49.60
r ₆ = -169.5222 d ₆ = 2.9063
r ₇ = 55.0218 d ₇ = 10.0561 n _Three = 1.77250 ν _Three = 49.60
r ₈ = 454.8651 d ₈ = 2.9491 n _Four = 1.69895 ν _Four = 30.12
r ₉ = 101.3179 d ₉ = 52.0001
r _Ten = ∞ d _Ten = -101.1950
r ₁₁ = -66.3150 d ₁₁ = -8.0907 n _Five = 1.83400 ν _Five = 37.17
r ₁₂ = 675.3393 d ₁₂ = -0.2000
r ₁₃ = -24.2696 d ₁₃ = -13.4254 n ₆ = 1.77250 ν ₆ = 49.60
r ₁₄ = 439.1123 d ₁₄ = -3.1588 n ₇ = 1.69895 ν ₇ = 30.12
r ₁₅ = -12.9765 d ₁₅ = -16.8685
r ₁₆ = 13.7225 d ₁₆ = -3.3430 n ₈ = 1.63980 ν ₈ = 34.48
r ₁₇ = -65.8002 d ₁₇ = -9.3438 n ₉ = 1.63854 ν ₉ = 55.38
r ₁₈ = 23.0053 d ₁₈ = -2.5776
r ₁₉ = 85.2345 d ₁₉ = -5.4035 n _Ten = 1.56907 ν _Ten = 71.30
r ₂₀ = 30.3318 d ₂₀ = -40.0000
r _{twenty one} = ∞ d _{twenty one} = 61.2877
r _{twenty two} = -42.6404 d _{twenty two} = 4.0000 n ₁₁ = 1.77250 ν ₁₁ = 49.60
r _{twenty three} = -58.6786 d _{twenty three} = 0.2000
r _{twenty four} = 192.4150 d _{twenty four} = 8.0000 n ₁₂ = 1.77250 ν ₁₂ = 49.60
r _{twenty five} = -54.1481 d _{twenty five} = 67.1580
r ₂₆ = 24.2145 d ₂₆ = 2.0000 n ₁₃ = 1.71736 ν ₁₃ = 29.51
r ₂₇ = 21.8905 d ₂₇ = 2.000
r ₂₈ = 33.3280 d ₂₈ = 5.0000 n ₁₄ = 1.62280 ν ₁₄ = 57.06
r ₂₉ = 203.6289 d ₂₉ = 94.9900
r ₃₀ = ∞
In the optical system of this data, the imaging magnification of the first intermediate optical system is 0.4 times the same as the optical system of FIG. 13, the imaging magnification of the optical system LS3 is 1, and the focal length of the eyepiece optical system is 65 mm.
[0080]
In the above data, r ₁ Is the photographic optical system LS, r ₂ Is the aperture, r _Three ~ R ₉ Is the first intermediate optical system LS1, r _Ten Is the reflector M1, r ₁₁ ~ R ₂₀ Is the viewfinder optical system LS3, r _{twenty one} Is the reflector M2, r _{twenty two} ~ R ₂₉ Is an eyepiece optical system, r ₃₀ Is the eye point position.
[0081]
FIGS. 15A and 15B are schematic views of another eighth embodiment. FIG. 15A is a state where the imaging unit is inserted into the camera body, and FIG. 15B is a diagram where the camera body and the imaging unit are separated. FIG. This embodiment has the same configuration as that of the first embodiment shown in FIG. 1, but in this embodiment, the imaging unit 4 is mounted with the mounting insertion portion 4b, and the imaging unit includes the mounting insertion portion 4b. 4 is a configuration in which a part (the front part) of the second intermediate optical system (relay lens LS2) is arranged.
[0082]
In the eighth embodiment, at the time of observation, only the photographing lens unit 1, the intermediate lens unit 10, and the camera body 2 are used, and the quick return mirror M1 is lowered to perform observation with the finder 3. At the time of imaging, the quick return mirror M1 of the camera body 2 is raised as shown in FIG. 15B, and the mounting insertion portion 4b of the imaging unit 4 is inserted into the camera body as shown in FIG. And fix it to the camera body. In this state, the subject light is imaged on the light receiving surface of the image sensor by the combined optical system of the photographing optical system, the first intermediate optical system, and the second intermediate optical system. That is, the second intermediate optical system is configured so that the re-imaging position by the second intermediate optical system becomes the light receiving surface.
[0083]
An example of the second intermediate optical system used in this embodiment is shown in FIG. The lens data is as follows.
r ₀ = ∞ d ₀ = ∞
r ₁ = ∞ d ₁ = 10.0000
r ₂ = ∞ d ₂ = 42.3094
r _Three = -41.4782 d _Three = 10.1468 n ₁ = 1.51633 ν ₁ = 64.15
r _Four = -37.8262 d _Four = 8.0223
r _Five = 108.6632 d _Five = 10.4838 n ₂ = 1.77250 ν ₂ = 49.60
r ₆ = -103.0068 d ₆ = 0.4924
r ₇ = 30.6846 d ₇ = 16.1745 n _Three = 1.60311 ν _Three = 60.68
r ₈ = -418.3918 d ₈ = 3.2298 n _Four = 1.80518 ν _Four = 25.43
r ₉ = 48.9807 d ₉ = 31.1212
r _Ten = -25.8909 d _Ten = 2.2000 n _Five = 1.48749 ν _Five = 70.21
r ₁₁ = 74.5986 d ₁₁ = 10.9097
r ₁₂ = 2625.6601 d ₁₂ = 13.2936 n ₆ = 1.77250 ν ₆ = 49.60
r ₁₃ = -33.6700 d ₁₃ = 1.6246
r ₁₄ = 44.4341 d ₁₄ = 16.9630 n ₇ = 1.83400 ν ₇ = 37.17
r ₁₅ = 227.6967 d ₁₅ = 4.7771
r ₁₆ = -43.0586 d ₁₆ = 2.8977 n ₈ = 1.60342 ν ₈ = 38.02
r ₁₇ = 31.3949 d ₁₇ = 7.1531
r ₁₈ = ∞ (aperture) d ₁₈ = 9.1042
r ₁₉ = -19.4177 d ₁₉ = 1.7983 n ₉ = 1.72825 ν ₉ = 28.46
r ₂₀ = -60.4697 d ₂₀ = 8.4471 n _Ten = 1.81600 ν _Ten = 46.62
r _{twenty one} = -29.6940 d _{twenty one} = 1.8512
r _{twenty two} = -81.8550 d _{twenty two} = 2.4404 n ₁₁ = 1.69895 ν ₁₁ = 30.12
r _{twenty three} = -222.0465 d _{twenty three} = 12.2354 n ₁₂ = 1.81600 ν ₁₂ = 46.62
r _{twenty four} = -55.6437 d _{twenty four} = 0.2000
r _{twenty five} = 246.1377 d _{twenty five} = 12.2716 n ₁₃ = 1.56907 ν ₁₃ = 71.30
r ₂₆ = -67.0378 d ₂₆ = 0.2449
r ₂₇ = 99.1945 d ₂₇ = 7.8527 n ₁₄ = 1.56907 ν ₁₄ = 71.30
r ₂₈ = -231.6542 d ₂₈ = 0.2000
r ₂₉ = 54.3321 d ₂₉ = 13.6397 n ₁₅ = 1.48749 ν ₁₅ = 70.21
r ₃₀ = -79.3281 d ₃₀ = 1.8361 n ₁₆ = 1.72825 ν ₁₆ = 28.46
r ₃₁ = 93.9123 d ₃₁ = 4.6019
r ₃₂ = ∞ d ₃₂ = 5.0000 n ₁₇ = 1.51633 ν ₁₇ = 64.15
r ₃₃ = ∞ d ₃₃ = 1.000
r ₃₄ = ∞ d ₃₄ = 55.0000 n ₁₈ = 1.58267 ν ₁₈ = 46.39
r ₃₅ = ∞ d ₃₅ = 4.9813
r ₃₆ = ∞
In the optical system shown in FIG. 16 and data of this optical system, r ₁ Is the photographic optical system LS, r ₂ Is the aperture, r _Three ~ R ₉ Is the first intermediate optical system LS1, r _Ten ~ R ₃₁ Is the second intermediate optical system LS2, r ₃₂ ~ R ₃₃ Is an optical element such as an infrared cut filter, r ₃₄ ~ R ₃₅ Is a three-color separation prism, and r ₁₈ Is a stop of the second intermediate optical system.
[0084]
As described above, FIG. 16 and data include the photographing optical system and the intermediate optical system. As shown in this figure and data, in this embodiment, as shown in FIG. 16, a part of the imaging unit (insertion part for attachment) is inserted into the camera body, so that the second intermediate optical system is the first intermediate optical system. The design can be made close to the intermediate optical system. That is, the distance d between the first intermediate optical system LS1 and the second intermediate optical system LS2. _Four Is relatively small. As a result, the subject light can be imaged on the light receiving surface of the image sensor while a part of the second intermediate optical system is inserted into the camera body. That is, the depth of the imaging unit can be shortened. The distance from the imaging surface of the first intermediate optical system of the optical system shown in FIG. 14 to the imaging surface of the second intermediate optical system (the light receiving surface of the image sensor) is 145 mm.
[0085]
FIG. 17 is a diagram illustrating the insertion of the mounting insertion portion of the image pickup unit 4, the switching of the quick return mirror, and other controls in the eighth embodiment.
[0086]
In the figure, the camera body 2 and the like shown at the upper left shows a state in which the mounting insertion portion of the eighth embodiment shown in FIG. 16A is inserted. . In this circuit diagram, 12 is an imaging circuit, 13 is a signal conversion circuit, 14 is a display drive unit, 15 is a CPU, 16 is a trigger circuit, 17 is a CCD drive unit, 18 is an insertion drive unit, 19 is a mirror control unit, 20 Is a display display unit.
[0087]
In the figure, a signal from the image pickup device 11 disposed behind the three-color separation filter P1 is input to the image pickup circuit 12. This signal is imaged by the imaging circuit 12 and output to the signal processing circuit 13. On the other hand, the display signal processed by the imaging circuit 12 is converted into a display signal and displayed on the display 20 via the display drive circuit 14.
[0088]
On the other hand, an insertion detection unit (not shown) is disposed in the camera body 2, and when the attachment insertion unit of the imaging unit 4 is inserted, the connection unit 2 b of the camera body 2 and the connection unit 4 a of the imaging unit 4. Is provided with a mechanical switch (not shown). Then, the mechanical switch is turned on when the mounting insertion portion of the imaging unit 4 is inserted into the camera body 2. When the insertion detection unit 18 detects this ON signal, a signal is sent to the CPU 15. The CPU 15 recognizes this detection signal, performs mirror control, and raises the quick return mirror. At the same time, display driving is performed based on a signal from the CPU 15 and an image based on subject light can be displayed on the display 14.
[0089]
The control is performed by the CPU 15 as described above, and this control is shown in a flowchart in FIG. As shown in this figure, when the sequence starts, it is determined whether or not the imaging unit is connected to the camera body (181). When the imaging unit is not connected, the control is finished as it is. When the imaging unit is connected, the mirror is flipped up and fixed as described above, the display circuit 14 of the display 20 is driven, and the process is terminated.
[0090]
FIG. 19 is a schematic diagram showing the configuration of the ninth embodiment. In this embodiment, the length of the imaging unit in the depth direction is further shortened by bending the optical path of the optical system by 90 °. That is, in this embodiment, the reflection optical system M3 is arranged in the image pickup unit 4 so that the optical path of the subject light emitted from the camera body and incident on the image pickup unit is reflected and bent downward by 90 °. Thus, the depth direction of the imaging unit, that is, the length in the direction along the optical axis of the photographing optical system is shortened.
[0091]
【The invention's effect】
(1) The camera system according to claim 1 of the present invention uses a large screen size photographing optical system to pick up an image on a small image pickup device, and has a well-balanced device in which the depth of the image pickup unit is small. It can be done. In addition, it is possible to realize a camera system in which a finder image is easy to see and capable of good imaging.
(2) If the intermediate lens unit according to claim 2 of the present invention is used in a camera system that captures an image on a small image sensor using a photographing optical system having a large screen size, the depth of the imaging unit in the camera system Can be made small, and can be made into a well-balanced device. In addition, it is possible to realize a camera system in which a finder image is easy to see and capable of good imaging.
(3) The imaging unit according to the third aspect of the present invention has a small depth dimension of the imaging unit and is balanced when used in a camera system that takes an image on a small imaging device using a photographing optical system having a large screen size. It can be made into a good device. In addition, it is possible to realize a camera system in which a finder image is easy to see and capable of good imaging.
(4) According to the invention of claim 4, a change in the light amount drop characteristic (peripheral light amount characteristic) of the peripheral portion of the screen due to the photographing optical system of different types of photographing lens units is reduced. When the imaging unit includes a color separation dichroic prism, uneven color in the screen due to oblique incidence on the prism can be prevented.
(5) According to the invention of claim 5, in addition to the effect of the invention of claim 4, the exit pupil position can be corrected steplessly according to the movement of the lens.
(6) According to the invention of claim 6, since it is not necessary to secure a moving space in the optical axis direction, in addition to the effect of the invention of claim 4, the size of the intermediate lens unit in the optical axis direction can be reduced.
(7) According to the invention of claim 7, since it is not necessary to secure a moving space in the optical axis direction, the size of the intermediate lens unit can be reduced. Further, the exit pupil position can be corrected steplessly according to the movement of the lens.
(8) According to invention of Claim 8, the depth dimension of an imaging unit becomes small, and a photography range and a finder visual field correspond. Further, the finder-side imaging position does not change depending on the presence or absence of the intermediate lens unit.
(9) According to the invention of claim 9, since only the optical axis is moved, in addition to the effect of the invention of claim 8, the radial dimension of the intermediate optical system can be reduced.
(10) According to the invention of claim 10, since it is not necessary to secure a moving space in the optical axis direction, in addition to the effect of the invention of claim 8, the dimension of the intermediate optical system in the optical axis direction can be reduced.
(11) According to the invention of claim 11, the photographing time is shortened. Also, since the shooting operation is reduced, the usability is improved.
(12) According to the twelfth aspect of the present invention, the depth dimension of the photographing unit is reduced, and a large finder image can be observed and is easy to use. Also, the shooting range matches the viewfinder field of view. Further, since the viewfinder is a look-in type, it becomes an easy-to-see viewfinder that can block (cut) harmful light such as sunlight. Moreover, since an eyepiece is not required, the optical system can be simplified.
(13) According to the invention of claim 13, the depth dimension of the imaging unit is reduced.
(14) According to the fourteenth aspect of the present invention, since mirror-up is automatically prohibited, there is no erroneous operation and it is easy to use. In addition, since it is automatically displayed, the number of operations is reduced, and the usability in shooting is improved.
(15) According to the invention of claim 15, the depth dimension of the imaging unit is reduced.
[Brief description of the drawings]
FIG. 1 is a schematic diagram of a first embodiment of a camera system of the present invention.
FIG. 2 is a diagram showing a configuration of an optical system used in the first embodiment.
FIG. 3 is a schematic view of a modification of the first embodiment.
FIG. 4 is a schematic view of another modification of the first embodiment.
FIG. 5 is a diagram showing a configuration of an optical system according to a second embodiment of the present invention.
FIG. 6 is a diagram showing the configuration of another optical system according to the second embodiment of the present invention.
FIG. 7 is a diagram showing a configuration of a third exemplary embodiment of the present invention.
FIG. 8 is a diagram showing another configuration of the third exemplary embodiment of the present invention.
FIG. 9 is a diagram showing another configuration of the third exemplary embodiment of the present invention.
FIG. 10 is a diagram showing a configuration of an optical system according to a fourth embodiment of the present invention.
FIG. 11 is a schematic view of a fifth embodiment of the present invention.
FIG. 12 is a diagram showing the focal length switching timing in the fourth and fifth embodiments.
FIG. 13 is a diagram showing a configuration of an optical system according to a sixth embodiment of the present invention.
FIG. 14 is a diagram showing the configuration of another optical system according to the seventh embodiment of the present invention.
FIG. 15 is a schematic diagram of an eighth embodiment of the present invention.
FIG. 16 is a diagram showing an optical system used in the eighth embodiment.
FIG. 17 is a circuit diagram for controlling the eighth embodiment.
FIG. 18 is a flowchart of the control.
FIG. 19 is a schematic view of a ninth embodiment of the present invention.
FIG. 20 is a schematic diagram of a conventional camera system.
FIG. 21 is a diagram showing a configuration of an optical system used in a conventional camera system.
[Explanation of symbols]
1 photographic lens unit, 2 camera body, 3 viewfinder,
4 imaging unit, 5 intermediate lens unit, LS imaging optical system,
LS1 first intermediate optical system, LS2 second intermediate optical system

Claims (15)

A photographic lens unit including a photographic optical system that forms an image of subject light at a predetermined position in the camera body and including a first lens mount portion that can be connected to a camera mount portion provided in the camera body; and the photographic lens Including a first intermediate optical system that is inserted between a unit and the camera body and that emits subject light emitted from the photographing optical system in the photographing lens unit and emits the light toward the camera body. An intermediate lens unit including a second lens mount portion that can be connected to the first lens mount portion of the photographing lens unit and a third lens mount portion that can be connected to the camera mount portion of the camera body; An image pickup unit having an image pickup unit connection portion connected to a camera body connection portion provided on the opposite side of the camera mount portion. Subject light emitted from the photographing optical system in the photographing lens unit together with the first intermediate optical system in the intermediate lens unit when the unit connects the intermediate lens unit to which the photographing lens unit is connected to the camera body. A camera comprising: a second intermediate optical system for re-imaging; and an imaging means for converting the received object light into an electrical signal and outputting it by placing an image receiving surface at a re-imaging position by the second intermediate optical system system. A photographic lens unit including a photographic optical system that forms an image of subject light at a predetermined position in the camera body and including a first lens mount portion that can be connected to a camera mount portion provided in the camera body; and the photographic lens Including a first intermediate optical system that is inserted between a unit and the camera body and that emits subject light emitted from the photographing optical system in the photographing lens unit and emits the light toward the camera body. An intermediate lens unit including a second lens mount portion that can be connected to the first lens mount portion of the photographing lens unit and a third lens mount portion that can be connected to the camera mount portion of the camera body; The object light emitted from the connecting lens corresponding to the connector and the photographing lens unit and passing through the intermediate lens unit and the camera body is imaged. In the intermediate lens unit to be applied to a camera system including an imaging unit having an imaging unit having an imaging surface, the imaging unit contributes to re-imaging subject light on the imaging surface of the imaging unit. A second intermediate optical system, wherein the first intermediate optical system is connected to the camera body and the first intermediate optical system is connected to the camera body when the imaging lens unit is connected to the camera body; An intermediate lens unit configured to re-image subject light on the imaging surface together with a second intermediate optical system. A photographic lens unit including a photographic optical system that forms an image of subject light at a predetermined position in the camera body and including a first lens mount portion that can be connected to a camera mount portion provided in the camera body; and the photographic lens Including a first intermediate optical system that is inserted between a unit and the camera body and that emits subject light emitted from the photographing optical system in the photographing lens unit and emits the light toward the camera body. An intermediate lens unit comprising a second lens mount that can be connected to the first lens mount of the photographic lens unit and a third lens mount that can be connected to the camera mount of the camera body, and the photographic lens unit The intermediate lens unit and the camera are ejected when the intermediate lens unit connected to the camera body is connected to the camera body. Application to a camera system including an imaging unit having a second intermediate optical system that contributes to the imaging of subject light that has passed through the body and an imaging means having an imaging surface at the imaging position of the second intermediate optical system An imaging unit that should be connected to the intermediate lens unit to which the photographing lens unit is connected is connected to the camera body, and subject light emitted from the photographing optical system when the imaging unit is connected to the camera body. An image pickup unit including a second intermediate optical system that re-images the image pickup surface of the image pickup unit together with the first intermediate optical system. The camera system of claim 1, the intermediate lens unit of claim 2, wherein the first intermediate optical system of the intermediate lens unit includes means for correcting an exit pupil position of the photographing optical system of the photographing lens unit. The imaging unit according to claim 3. 5. The exit pupil position of the photographic optical system is corrected by moving at least a part of the lenses according to the type of photographic lens unit to which the first intermediate optical system is composed of a plurality of lenses. Camera system, intermediate lens unit or imaging unit. 5. The camera system, intermediate lens unit, or photographing according to claim 4, wherein the first intermediate optical system is selected according to the type of the photographing lens unit to which the first intermediate optical system is connected, and the first intermediate optical system is detachably disposed. unit. The camera system according to claim 4, comprising an optical element made of a transparent elastic material whose refractive power is mechanically variable or a liquid crystal material whose refractive power is electrically variable in the first intermediate optical system. Or an imaging unit. The first intermediate optical system in the intermediate lens unit can be switched between a first focal length and a second focal length, and the camera body includes a finder, the finder side, and an imaging surface side in the imaging unit. And a reflecting optical system for switching the optical path, and by switching the reflecting optical system, at the time of framing, the first intermediate optical system is set to a first focal length suitable for this, and the subject light is guided to the viewfinder side for imaging. 4. The camera system of claim 1, the intermediate lens unit of claim 2, or the imaging of claim 3 wherein the first intermediate optical system is sometimes set to a second focal length suitable for this and the subject light is guided to the imaging surface. unit. 9. The camera system of claim 8, wherein the first intermediate optical system includes a lens that is movable on the optical axis between a position corresponding to the first focal length and a position corresponding to the second focal length. Intermediate lens unit or imaging unit. 9. The camera system, intermediate lens unit, or image pickup unit according to claim 8, wherein the first intermediate optical system is detachable from the outside in order to switch between the first focal length and the second focal length. 9. The camera system, the intermediate lens unit, or the camera system according to claim 8, wherein switching between the first focal length and the second focal length in the first intermediate optical system is performed in synchronization with a switching operation timing of the reflection optical system. Imaging unit. The camera system according to claim 1, the intermediate lens unit according to claim 2, or the imaging unit according to claim 3, further comprising a re-imaging optical system that magnifies and re-images subject light on the viewfinder side of the camera body. The imaging unit has a mounting insertion portion configured to include a distal portion of the second intermediate optical system, the insertion insertion portion is inserted into the camera body, and the imaging unit is attached to the camera body. The camera system of claim 1, the intermediate lens unit of claim 2, or the imaging unit of claim 3. The camera body includes a finder for framing and a reflection optical system that switches and directs subject light to the viewfinder side and the imaging surface side, and an insertion portion for attaching the imaging unit is inserted into the camera body and connected. 14. The camera system according to claim 13, further comprising control means for prohibiting the operation of the reflective optical system and causing the output signal from the image pickup means of the image pickup unit to be displayed on the applied image display means. Lens unit or imaging unit. The camera system according to claim 1, wherein the second intermediate optical system includes a reflective optical system, and subject light is totally reflected in a substantially right angle direction by the reflective optical system to form an image on an imaging surface of the imaging mechanism. The intermediate lens unit or the imaging unit according to claim 3.

Images