JP2004077852A

JP2004077852A - Photographing device

Info

Publication number: JP2004077852A
Application number: JP2002238773A
Authority: JP
Inventors: Kunihisa Yamaguchi; 山口　邦久; Junichi Shinohara; 篠原　純一; Keiichiro Hirahara; 平原　圭一郎; Naoki Koshida; 越田　直紀; Hiroyuki Chiba; 千葉　浩幸
Original assignee: Ricoh Co Ltd
Current assignee: Ricoh Co Ltd
Priority date: 2002-08-20
Filing date: 2002-08-20
Publication date: 2004-03-11
Anticipated expiration: 2022-08-20
Also published as: JP4064760B2

Abstract

PROBLEM TO BE SOLVED: To correct the influence of the mounting form or the mounting form and the shape of a flexible board on shake correction. SOLUTION: In the photographing device, an object image by a photographic optical system 3 is received by an imaging device 6 on an imaging means 13, the electrical signal of the image received by the imaging device 6 is fetched to an image processing part side from the imaging means by the flexible board to perform photography, and the shake of the optical system 3 around two orthogonal axes is detected, and the imaging means 13 is displaced in two orthogonal directions to correct the influence of the shake based on the shake detection amount. Then, control information to displace the imaging means is made different in two directions orthogonal to each other according to the mounting form of the flexible board, and the correction in the two orthogonal directions is performed based on the control information. COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
この発明はデジタルカメラ等の撮影装置に関する。
【０００２】
【従来の技術】
撮影光学系による被写体像を撮像手段の撮像素子により受光し、撮像素子が受光した画像の電気信号をフレキシブル基板により撮像手段から画像処理部側へ取り込んで撮影を行う撮影装置は、デジタルカメラ等として知られているが、撮影の際の「（手振れ等の）振れの影響」を補正するために、撮影光学系の光軸に直交する直交２軸の回りの「振れ」を振れ検出手段により検出し、検出される振れ検出量に基づき、振れ補正手段により、撮像手段を「振れの方向に対応する直交２方向」に変位させて、被写体像と撮像素子の相対的な変位量を軽減させることが行なわれている。
【０００３】
このような「振れ補正」は、撮像素子の変位動作を露光中全体にわたって、各方向とも、所定時間期をもって繰り返される。
【０００４】
振れの程度は、振れ検出手段により、振れ検出量として高精度に検出され、それに基づいて演算される撮像手段の変位量も高精度であるが、実際に実行される補正動作においては、必ずしも十分な精度の補正が行われない。
【０００５】
発明者はこの問題につき研究を重ねた結果、画像信号を撮像手段から画像処理部側へ取り込むフレキシブル基板が、その形状や取り付け形態により、振れ補正のための「撮像素子の変位駆動」に対して、線形または非線形な影響を与えることを見出した。
【０００６】
【発明が解決しようとする課題】
この発明は上述した事情に鑑み、振れ検出量に基づき算出される振れ補正量に基づく制御に加え、フレキシブル基板の取り付け形態、もしくは取り付け形態と形状とによる影響を補正する制御を行なうことにより、振れ補正の効果を向上させることを課題とする。
【０００７】
【課題を解決するための手段】
この発明の撮影装置は「撮影光学系による被写体像を撮像手段の撮像素子により受光し、撮像素子が受光した画像の電気信号をフレキシブル基板により撮像手段から画像処理部側へ取り込んで撮影を行う撮影装置であって、撮影光学系の光軸に直交する直交２軸の回りの振れを、振れ検出手段により検出し、検出される振れ検出量に基づき、振れ補正手段により撮像手段を振れの方向に対応する直交２方向に変位させて、振れの影響を補正するもの」である。
【０００８】
この明細書において「振れ」は、撮影者の「手振れ」が代表的であるが、これに限らず、撮影装置を自動車や飛行機、遠隔操作の走行体等に装着した場合の被装着体による振れ等をも含む。
【０００９】
請求項１記載の撮影装置は「記憶手段に記憶され、撮像手段を変位させる制御情報を、フレキシブル基板の取り付け形態に応じて、互いに直交する２方向につき異ならせ、これら制御情報に基づき直交２方向の補正を行う」ことを特徴とする。「互いに直交する２方向」は、撮像手段を変位させる２方向である。
【００１０】
請求項２記載の撮影装置は、請求項１記載の撮影装置において「フレキシブル基板の取り付け形態により、互いに直交する２方向につき各々異なる弾性成分の影響を補正するように制御情報の各々を定めた」ことを特徴とする。
【００１１】
請求項３記載の撮影装置は、請求項１記載の撮影装置において「フレキシブル基板の取り付け形態により、互いに直交する２方向につき各々異なる抵抗成分の影響を補正するように制御情報の各々を定めた」ことを特徴とする。
【００１２】
請求項４記載の撮影装置は「記憶手段に記憶され、撮像手段を変位させる制御情報を、フレキシブル基板の形状及び取り付け形態に応じて、互いに直交する２方向につき異ならせ、これら制御情報に基づき、直交２方向の補正を行う」ことを特徴とする。
【００１３】
上記請求項１〜４の任意の１に記載の撮影装置は「フレキシブル基板の温度を検出する温度検出手段を有し、この温度検出手段の検出出力により、制御情報の補正を行う」ことができる（請求項５）。
【００１４】
上記請求項１〜５の任意の１に記載の撮影装置において「振れ補正手段により撮像手段を変位させる力」は弾性力とすることができる（請求項６）。
【００１５】
【発明の実施の形態】
以下、発明の実施の形態を説明する。
【００１６】
図１は、撮影装置の１例（デジタルカメラ）を示している。
符号１は「撮影装置」、符号２は「撮影レンズ」、符号３は撮影レンズ２を含む「撮影光学系」、符号２５は「シャッタボタン」を示す。
【００１７】
図１に示すようにＸ及びＹ軸を設定すると、（手振れ等による）Ｘ軸の回りの振れにより被写体像は撮像手段に対しＹ方向（シャッタボタン２５の押し下げ方向）に変動する。また、Ｙ軸の回りの振れによっては、被写体像は撮像手段に対してＸ方向に変動する。「振れ補正」は、撮像手段を変位させることにより、撮像素子の受光面と被写体像との相対的な変動を０に近づける動作である。
【００１８】
図２は、撮影装置１において、振れ補正を実施する部分を説明図的に示している。符号４および５は「振れ検出センサ」を示す。符号１３で示す「撮像手段」はＣＣＤ等による撮像素子６を含む。振れ検出センサ４は、撮影装置１の「Ｘ軸の回りの振れ」を検出するためのセンサであり、振れ検出センサ５は、撮影装置１の「Ｙ軸の回りの振れ」を検出するためのセンサである。
【００１９】
振れ検出センサ４、５の検出量は、振れ検出センサ回路７により信号化されて「振れ検出量」となる。これら振れ検出センサ４、５と振れ検出センサ回路７は振れ検出手段８を構成する。
【００２０】
振れ検出手段８の出力は演算手段９に送られる。演算手段９はマイクロプロセッサ等で構成され、振れ検出手段８から入力される振れ検出量に基づき、所定の演算を実行して「振れ補正量」を算出し、これを信号として補正手段駆動回路１０に送る。
【００２１】
補正手段駆動回路１０は、入力信号に応じて振れ補正手段１１、１２を駆動する。振れ補正手段１１は、撮像素子６をＹ方向において「Ｘ軸の回りの振れを軽減させる向き」に変位させる。振れ補正手段１２は撮像素子６をＸ方向において「Ｙ軸の回りの振れを軽減させる向き」に変位させる。このような一連の振れ補正動作は「露光中に繰り返し」て行われる。
【００２２】
図３は、振れ補正手段１１、１２による、撮像素子６の変位を説明するための図である。
撮像素子６を保持した撮像手段１３は、図示の如く、鉤型に形成された与圧ばね１４の各バネ面に、ローラ２０１、２０２を介して当接している。
振れ補正手段１１は、圧電素子１５１とその動作方向両端に固定された取り付け板１７１Ａ、１７１Ｂと、これら取り付け板１７１Ａ、１７１Ｂに湾曲状態で取り付けられた２つの板ばね１６１Ａ、１６１Ｂと、板ばね１６１Ａの中央部と撮像手段１３とで挟持されたローラ１８１と、板ばね１６１Ｂの中央部を押さえる押えねじ１９１により構成されている。
【００２３】
同様に、振れ補正手段１２は、圧電素子１５２とその動作方向両端に固定された取り付け板１７２Ａ、１７２Ｂと、これら取り付け板１７２Ａ、１７２Ｂに湾曲状態で取り付けられた２つの板ばね１６２Ａ、１６２Ｂと、板ばね１６２Ａの中央部と撮像手段１３とで挟持されたローラ１８２と、板ばね１６２Ｂの中央部を押える押えねじ１９２により構成されている。
【００２４】
圧電素子１５１に「駆動電圧」が印加されない状態においては、押えねじ１９１から作用される「図の上向きの力」が、板ばね１６１Ａ、１６１Ｂの弾性力となって撮像素子１３に上向きに作用し、この上向きの力が与圧ばね１４による下向きの力と釣り合う。押えねじ１９１を調整することにより、撮像素子１３の上下方向、即ち「Ｙ軸方向」の位置を調整できる。
【００２５】
同様に、圧電素子１５２に駆動電圧が印加されない状態においては、押えねじ１９２から作用される図の右向きの力が、板ばね１６２Ａ、１６２Ｂの弾性力となって撮像素子１３に右向きに作用し、この右向きの力が与圧ばね１４による左向きの力と釣り合う。押えねじ１９２を調整することにより、撮像素子１３の左右方向、即ち「Ｘ軸方向」の位置を調整できる。
【００２６】
圧電素子１５１、１５２に「センタリング電圧」を印加することにより、撮像素子６の受光面の中央を、撮影光学系の光軸位置に位置させる。
【００２７】
圧電素子１５１に「正方向の駆動電圧」が印加されると圧電素子１５が、センタリング状態よりも動作方向（図３の左右方向）に伸び、板ばね１６１Ａ、１６１Ｂは両端を引張られて湾曲の曲率半径が増大し、板ばね１６１Ａ、１６１Ｂの間隔が広がる。
【００２８】
板ばね１６１Ａは押えねじ１９１により押えられているので、板ばね１６１Ａ、１６１Ｂの変形はローラ１８１を介して撮像手段１３を図３の上向きに変位させる。
【００２９】
圧電素子１５１に「負方向の駆動電圧」が印加されると圧電素子１５１がセンタリング状態よりも動作方向（図３の左右方向）に縮み、板ばね１６１Ａ、１６１Ｂの湾曲の曲率半径が減少し、板ばね１６１Ａ、１６１Ｂの間隔が狭まり、撮像素子１３は与圧ばね１４の下向きの力に押されて図３の下向きに変位する。
【００３０】
撮像手段１３のＹ方向（図の上下方向）の変位は、ローラ１８２、２０２の回転により滑らかに行われる。
【００３１】
同様に、圧電素子１５２に「正（負）方向の駆動電圧」が印加されると圧電素子１５２が動作方向（図３の上下方向）に伸び（縮み）、板ばね１６２Ａ、１６２Ｂの湾曲の曲率半径が増大（減少）し、板ばね１６２Ａ、１６２Ｂの間隔が広がり（狭まり）、撮像素子１３は与圧ばね１４の左向きの力に抗し（押され）て図３の右（左）向きに変位する。撮像手段１３のＸ方向（図の左右方向）への変位は、ローラ１８１、２０１の回転により滑らかに行われる。
【００３２】
圧電素子１５１の動作方向の変形量は板ばね１６１Ａ、１６１Ｂにより、圧電素子１５２の動作方向の変形量は板ばね１６２Ａ、１６２Ｂにより、それぞれ６〜７倍に増幅される。
【００３３】
図４は、「電気信号を図示されない画像形処理装置側へ取り込むため」のフレキシブル基板２１を撮像手段１３に取り付けた「取り付け形態の１例」を示している。フレキシブル基板２１は、その一端が撮像手段１３に取り付けられ、他端はソケット２２により本体側電子基盤と繋がっている。
【００３４】
図４の（ａ）は、フレキシブル基板２１を取り付けた撮像手段１３を、ＣＣＤである撮像素子６の受光面に直交する方向（以下「正面方向」という）から見た状態を示し、（ｂ）は、撮像素子６の受光面に平行な方向（図４（ａ）のＸ方向、以下「横方向」という）から見た状態を示している。
【００３５】
図４（ａ）、（ｂ）は、上述した振れ補正手段１１、１２の圧電素子１５１、１５２に「センタリング電圧」が印加されている状態を示し、撮像手段１３は補正範囲に対して中心位置にある。このときの「撮像素子６の中心の位置（撮影光学系の光軸に合致する位置）」をＸ、Ｙ方向の原点位置とする。
【００３６】
振れ補正手段１１、１２の圧電素子１５１、１５２に駆動電圧が印加されると、圧電素子１５１、１５２の（駆動電圧に応じた）伸縮が、板ばね１６１Ａ、１６１Ｂ、１６２Ａ、１６２Ｂによりそれぞれ拡大され、ローラ１８１、１８２、２０１、２０２を介して、撮像手段１３をＸ、Ｙ方向に変位させる。
【００３７】
図５（ａ）に示すように、撮像手段１３がＸ方向へ変位すると、フレキシブル基板２１は、同図の上または下の図に示すように変形する。また、撮像手段１３がＹ方向への変位駆動されると、フレキシブル基板２１は、図５（ｂ）のようにその「たわみ状態」が変化する。
【００３８】
このような、フレキシブル基板２１の「Ｘ方向の変形」及び「Ｙ方向のたわみ状態の変化」は撮像手段１３の駆動動作、即ち、振れ補正動作に影響する。
その結果、撮像手段１３は「振れ検出手段８より検出される振れ検出量に基づき、所定の演算を施し算出された振れ補正量に基づく制御」どおりには変位せず「期待通りの振れ補正効果」が得られなくなる。
【００３９】
そこでこの発明では、撮像素子６を変位させる制御情報を、フレキシブル基板の取り付け形態に応じて、互いに直交する２方向（Ｘ及びＹ方向）について異ならせ、これら制御情報に基づいて上記直交２方向の補正を行う。
【００４０】
即ち、図２に示す記憶手段２３に、フレキシブル基板２１の「取り付け形態により異なる制御情報」を記憶させておき、この制御情報を基に、演算手段９において駆動方向（Ｘ方向、Ｙ方向）毎に異なる影響を補正する演算を行う。
【００４１】
上に、図１〜図５に即して実施の形態を説明した撮影装置は「撮影光学系３による被写体像を撮像手段１３の撮像素子６により受光し、撮像素子６が受光した画像の電気信号をフレキシブル基板２１により撮像手段１３から画像処理部側へ取り込んで撮影を行う撮影装置１であって、撮影光学系３の光軸に直交する直交２軸の回りの振れを、振れ検出手段８により検出し、検出される振れ検出量に基づき、振れ補正手段１１、１２により撮像手段１３を振れの方向に対応する直交２方向に変位させて振れの影響を補正するものにおいて、記憶手段２３に記憶され、撮像手段１３を変位させる制御情報を、フレキシブル基板２１の取り付け形態に応じて、互いに直交する２方向につき異ならせ、これら制御情報に基づき、直交２方向の補正を行うものである（請求項１）。
【００４２】
このように、振れ検出手段８より検出される振れ検出量に基づき、所定の演算で算出された「振れ補正量に基づく制御」に加え、フレキシブル基板２１の取り付け形態により、撮像手段１３の駆動方向毎に異なる影響を補正する制御を行なうことで、撮影画像の振れ補正効果を向上させることができる。
【００４３】
図５（ａ）のように、撮像素子６をＸ方向に変位駆動する場合を考える。このときの変位駆動が行なわれるＸ方向は、フレキシブル基板２１の基板面に平行で長手方向に直交する方向である。
【００４４】
フレキシブル基板２１はソケット２２で固定されているため、フレキシブル基板を「弾性体」とすると、図６（ａ）に示す「長さ：ｌ、厚さ：ｂ、幅：ｈの板状の片持ち梁」と考えることができ、図６（ｂ）の如く単純化して考察できる。
【００４５】
図６（ｂ）に示すように、幅：ｈ方向の中立線について、片持ち梁の先端変位がΔｘとなる力：Ｆを想定すると、この場合の変形の断面２次モーメント：Ｉは周知の如く、
Ｉ＝ｂｈ^３／１２　　　　　　　（１）
であるから、力：Ｆと変位：Δｘは、Ｅをフレキシブル基板２１の材質によって決まる弾性係数として、関係：
Ｆ＝３ＥＩ／（ｌ^３・Δｘ）　　（２）
を満足する。
【００４６】
フレキシブル基板２１の弾性係数：Ｅは一般に比較的小さいものであるが、Ｘ方向のモーメントを考えた場合、片持ち梁の幅：ｈの値が大きく、断面２次モーメントＩは、（１）式のように幅：ｈの３乗に比例するので、片持ち梁の系としての全体の弾性係数をｋ２とすると、
ｋ２＝３ＥＩ／ｌ^３　　　　　　　（３）
となり、弾性係数：ｋ２は比較的大きな値となる。
【００４７】
ｋ２を用いて（２）式を書き直すと、
Ｆ＝ｋ２・Δｘ　　　　　　　　　（４）
となる。これがフレキシブル基板２１を上記の片持ち梁として考えたときの「弾性成分」である。
【００４８】
図７（ａ）は、フレキシブル基板２１の「弾性成分（弾性係数：ｋ２による弾性力：ｋ２・Δｘ）を無視できる場合」における、振れ補正手段１２による撮像手段１３の変位を示している。この場合、振れ補正手段１２の変位：Δｘ１はそのまま、撮像手段１３の変位：Δｘ１となる。
【００４９】
フレキシブル基板２１の上記弾性成分を無視できない場合には、図７（ｂ）に示すように、フレキシブル基板２１の弾性成分は、撮像手段１３の変位方向に対して逆方向の弾性力として作用する。
【００５０】
図３に即して説明したように、撮像手段１３をＸ方向へ変位させるための振れ補正手段１２は、圧電素子１５２の駆動方向の変形量を、板ばね１６２Ａ、１６２Ｂで弾性的に拡大しているのであるから、振れ補正手段１２自体も弾性成分を有している。
【００５１】
このため、フレキシブル基板２１の弾性成分を考慮せずに「変位：Δｘ１を実現する」ように圧電素子１５２を駆動すると、フレキシブル基板２１の弾性成分が無視できない場合には、板ばね１６２Ａ、１６２Ｂの変形が弾性成分の抗力により抑制され、撮像手段１３の実際の変位量：Δｘ２が「実現するべき変位量：Δｘ１」より小さくなって、所望の変位量：Δｘ１を実現できなくなる。
【００５２】
図８（ａ）は、図７（ｂ）における振れ補正手段１２の弾性成分を「弾性係数：ｋ１のばね」として模型化したものであり、図８（ｂ）は、図８（ａ）と等価な模型である。図８における弾性係数：ｋ１には、与圧ばね４の弾性成分も含まれている。
【００５３】
図８（ｂ）の模型を用い、フレキシブル基板２１の「弾性係数：ｋ２の弾性成分」と、振れ補正手段１２のもつ弾性係数：ｋ１の弾性成分とを考慮した「撮像手段１３のＸ方向の変位動作」を考察する。
【００５４】
図９（ａ）は、撮像手段１３が「センタリング位置」にある状態を示す。このときフレキシブル基板２１のＸ方向の変位がゼロであり、振れ補正手段１２の弾性成分から撮像手段１３に作用する力もゼロである。振れ補正手段１２の弾性係数：ｋ１は板ばね１６２Ａ、１６２Ｂの弾性成分と与圧ばね１４の弾性成分を含んだものであるため、板ばね１６２Ａ、１６２Ｂと与圧ばね１４の弾性力が釣り合った状態である。
【００５５】
図９（ｂ）は、圧電素子１５へのセンタリング電圧から「正方向の駆動電圧」の印加により、振れ補正手段１２の変位：Δｘ１、撮像手段１３の変位：Δｘ２で、弾性係数：ｋ１による弾性力と、弾性係数：ｋ２による弾性力が釣り合っている状態を示している。このときの力を「Ｆ」とすると、
Ｆ＝ｋ２・Δｘ２＝ｋ１（Δｘ１−Δｘ２）　　（５）
がなりたち、これをΔｘ２について解くと、
Δｘ２＝ｋ１／（ｋ１＋ｋ２）・Δｘ１　　　　　（６）
であるから、Δｘ２＜Δｘ１である。
【００５６】
即ち、フレキシブル基板２１の弾性成分を考慮したときの、撮像手段１３のＸ方向の変位における「全体の実効弾性係数」は（６）式により「ｋ１／（ｋ１＋ｋ２）」となる。フレキシブル基板２１の影響が無い場合、即ちｋ２＝０では、Δｘ２＝Δｘ１となり、先に説明したように、撮像手段１３の変位：Δｘ２は、振れ補正手段１２の変位：Δｘ１と同じになる。
【００５７】
図９（ｂ）に示すように、振れ補正手段１２の変位：Δｘ１、撮像手段１３の変位：Δｘ２に対する圧電素子１５２への印加電圧をＶとする。印加電圧：Ｖはセンタリング電圧に対する相対的な電圧値である。
【００５８】
図１０（ａ）の曲線：Ａ１で示すように「圧電素子駆動電圧波形」を振幅：Ｖの正弦波とすると、撮像手段１３の変位は、図１０（ｂ）に曲線：Ｂ１で示すように、振幅：Δｘ２、即ち、ｋ１／（ｋ１＋ｋ２）・Δｘ１の正弦波となるため、本来制御すべき撮像手段１３の変位である最大値：Δｘ１の正弦波を実現する電圧よりも小さい電圧となり、所望の変位：Δｘ１を実現することができず「振れ補正の精度」が低下してしまう。
【００５９】
そこで、図１０（ａ）に曲線：Ａ２で示すような「圧電素子駆動電圧波形が最大値：Ｖ・（ｋ１＋ｋ２）／ｋ１の正弦波」となるように補正手段駆動回路１０を制御することにより、図１０（ｂ）の曲線：Ｂ２のように、撮像手段１３の変位量を「本来制御すべき最大値：Δｘ１の正弦波」とすることができ、振れ補正効果を向上させることができる。
【００６０】
次に、フレキシブル基板２１の長手方向（図５の左右方向）であるＹ方向に撮像手段１３を変位駆動する場合を考察する。
図５（ｂ）に示すように、横方向から見ると、フレキシブル基板２１はＹ方向でのセンタリング位置での撓み状態（破線）が、Ｙ方向への変位に伴い、図５（ｂ）の上下の図のように変化する。
【００６１】
このように、横方向から見たフレキシブル基板２１は「ある曲率をもつばね」と考えることもできるが、この方向では断面２次モーメント：Ｉは、厚さ：ｂの３乗に比例し、厚さ：ｂが非常に小さいため、系全体としての弾性係数も非常に小さく、このためフレキシブル基板２１の弾性成分は、撮像手段１３のＹ方向への変位駆動にはほとんど影響を及ぼさない。
【００６２】
即ち、撮像素子１３のＹ方向への変位駆動においては、振れ検出センサ８により検出される振れ検出量に基づき、所定の演算で算出された振れ補正量に基づく制御だけで問題ない。
【００６３】
即ち、請求項２記載の撮影装置では「フレキシブル基板２１の取り付け形態により、互いに直交する２方向につき各々異なる弾性成分の影響を補正するように、制御情報の各々が定め」られる。
【００６４】
上に説明したところに即して具体的に言えば、振れ検出手段８が検出する振れ検出量に基づき、所定の演算で算出される振れ補正量を、Ｘ方向につきΔｘ、Ｙ方向につきΔｙとするとき、図２の記憶手段２３に「制御情報」として「振れ補正量に対する積因子」を記憶させておく。
【００６５】
「振れ補正量に対する積因子」は、振れ補正量：Δｙに対する積因子が「１」であり、振れ補正量：Δｘに対する積因子が「（ｋ１＋ｋ２）／ｋ１」である。従って、演算手段９は、振れ検出手段８が検出する振れ検出量に基づいて所定の演算で算出した補正量：Δｘ、Δｙに対し、記憶手段２３から読み出した上記積因子を乗じた「Δｘ（ｋ１＋ｋ２）／ｋ１」とΔｙ・１とを補正信号として補正手段駆動回路１０に送るのである。勿論、係数：ｋ１、ｋ２は実験的に定める。
【００６６】
このように、フレキシブル基板２１の取り付け形態により存在する各々異なる弾性成分の影響を、撮像手段１３の駆動方向毎に補正制御することで、撮影画像の振れ補正効果を向上させることができる。
【００６７】
図１１は、撮像手段１３へのフレキシブル基板２１の取り付けの別形態を示している。フレキシブル基板２１の一端は撮像手段１３に固定され、他端はソケット２２に挿入されている。
【００６８】
撮像手段１３のＸ方向への変位駆動を考えた場合、前述したようにフレキシブル基板２１の幅：ｈの３乗に比例して断面２次モーメント：Ｉが非常に大きいので、撮像手段１３のＸ方向の変位駆動に関しては、フレキシブル基板２１を「剛体」と考えることもできる。
【００６９】
そうすると、撮像手段１３のＸ方向への変位に伴い、フレキシブル基板２１は、例えば、図１１上図に示すように、ソケット２２との接触点Ｃを中心に回転することになるが、このときフレキシブル基板２１とソケット２２の接触部分では摩擦による「抵抗成分」が生じる。
【００７０】
また、例えば、図１１下図の「符号Ｅ１、Ｅ２で示す部分」のように、フレキシブル基板２１と撮影装置の本体Ｄとの間に接触部分があると、撮像手段１３をＸ、Ｙ方向のどちらの方向に変位駆動した場合でも、フレキシブル基板２１と本体Ｄとの間に摩擦による抵抗成分が生じる。このような抵抗成分は、振れ補正手段１１、１２による撮像手段１３の駆動動作に遅れを生じさせる。
【００７１】
振れ補正手段１１、１２における圧電素子駆動電圧波形が、図１２（ａ）に曲線：Ｈ１で示すような「最大値：Ｖの正弦波」である場合、この駆動電圧で変位駆動された撮像手段１３の変位は、図１２（ｂ）の曲線：Ｇ１のように「圧電素子駆動電圧波形よりΔｔだけ遅れた正弦波状」となり補正精度が低下する。
【００７２】
このような場合には、図１３（ａ）に示すように、圧電素子駆動波形：Ｈ１に対してΔｔの「予測演算」を行い、駆動波形として「位相がΔｔだけマイナス側にずれた正弦波：Ｈ２」を得る。正弦波：Ｈ２で振れ補正手段１１又は１２の圧電素子１５を駆動することで、図１３（ｂ）の曲線：Ｇ２のように、撮像手段１３の所望の変位動作を得ることができる。図１３（ｂ）における曲線：Ｇ１は予測演算を行なわないで変位駆動を行なった場合の変位動作である。
【００７３】
予測演算における遅れ時間：Δｔは、撮像手段１３の変位方向：Ｘ、Ｙで、動作に関わる摩擦状態が異なるため、変位方向により異なる遅れ時間：Δｔでの制御となる。
【００７４】
即ち、請求項３記載の撮影装置においては、フレキシブル基板２１の取り付け形態により「互いに直交する２方向（Ｘ、Ｙ）につき各々異なる抵抗成分」の影響を補正するように、制御情報の各々を定める。上に説明した場合について言えば、制御情報は「予測演算における遅れ時間：Δｔ」である。
【００７５】
振れ検出手段８が検出した振れ検出量に基づき、演算手段９は所定の演算により振れ補正量：Δｘ、Δｙを算出するが、記憶手段２３には、Ｘ、Ｙ２方向の各々に対する遅れ時間：Δｔｘ、Δｔｙを「予め実験的に特定」して記憶させておく。
【００７６】
そして、演算手段９は、記憶手段２３から読み出した上記遅れ時間：Δｔｘ、Δｔｙにより予測演算を行い、その結果を補正手段駆動回路１０に送る。
【００７７】
このように、フレキシブル基板２１の取り付け形態により、撮像手段の変位駆動方向（Ｘ、Ｙ方向）のそれぞれで異なる抵抗成分の影響を、撮像手段１３の駆動方向毎に制御することで、撮影画像の振れ補正効果を有効に向上させることができる。
【００７８】
図１１においては、フレキシブル基板２１の変位を「回転」として捉えたが、フレキシブル基板の撮像手段１３側の端部は、撮像手段１３のＸ方向に平行な側縁部に「幅：ｈにわたって固定され」ており、従って、図１４に示すように、撮像手段１３のＸ方向への変位駆動を考えた場合、フレキシブル基板２１の撮像手段１３に固定されている部分は「回転ではなく平行移動」するので、このように考えた場合、フレキシブル基板２１の、例えば、部分Ｐでは引っ張り応力、部分Ｑでは圧縮応力が発生する。また、フレキシブル基板２１の形状変化よりフレキシブル基板２１内でねじり成分が発生し、例えば、図１４下図に示すように、フレキシブル基板２１に「浮き上がり」などが発生する（図１４上図の符号Ｒで示す部分）。
【００７９】
さらに、フレキシブル基板２１とソケット２２の接触部分の「遊び」により、フレキシブル基板２１の変位・変形に伴なう接触面積の変化が一様でなかったりして、フレキシブル基板２１に摩擦力を介して作用する抵抗成分が変化したり、フレキシブル基板２１自体にある種の振動が生じたりする。
【００８０】
このような「フレキシブル基板２１に生じる種々の現象」が、撮像手段１３の変位駆動に影響し、例えば、図１５（ａ）に示すように「電圧に対する変位の変化が直線的に比例しな」かったり、図１５（ｂ）に示すように「電圧に対する変位の変化がヒステリシスとな」ったり、さらに、例えば、前述の遅れ時間：Δｔが撮像手段１３の移動速度により変化したりする。
【００８１】
このような影響は、フレキシブル基板２１の取り付け形態及びフレキシブル基板２１の形状に関係する特性であり、撮像手段１３の変位方向（Ｘ、Ｙ方向）により各々異なるが、何れも、その特性を制御因子として実験的に特定できるので、これら各方向についての制御因子を「制御情報」として記憶手段２３に記憶させておき、制御手段９により、振れ検出手段８が検出する「振れ検出量」に基づいて「振れ補正量」を算出し、記憶手段２３から読み出した制御因子により、補正量を調整して補正手段駆動回路１０に印加する信号を生成するのである。
【００８２】
即ち、請求項４記載の撮影装置は、撮影光学系３による被写体像を撮像手段１３の撮像素子６により受光し、撮像素子１３が受光した画像の電気信号をフレキシブル基板２１により撮像手段１３から画像処理部側へ取り込んで撮影を行う撮影装置であって、撮影光学系３の光軸に直交する直交２軸の回りの振れを、振れ検出手段８により検出し、検出される振れ検出量に基づき、振れ補正手段１１、１２により撮像手段１３を振れの方向に対応する直交２方向に変位させて、振れの影響を補正するものにおいて、記憶手段２３に記憶され、撮像手段を変位させる制御情報（上記制御因子）を、フレキシブル基板２１の「形状及び取り付け形態」に応じて、互いに直交する２方向につき異ならせ、これら制御情報に基づき、直交２方向の補正を行う。
【００８３】
このようにして、フレキシブル基板の取り付け形態・形状に関係した振れ補正への影響を、撮像手段１３の駆動方向毎に制御することで、撮影画像の振れ補正効果を向上させることができる。
【００８４】
上に説明した「フレキシブル基板２１の弾性係数：Ｅ」は温度変化に対して不変ではなく、温度変化に伴なって変化する。このため、（１）式で表される断面２次モーメント：Ｉも温度変化により変化することとなり、上に説明した請求項２、請求項４の場合において、Ｘ方向の撮像手段１３の駆動を考えた場合の系全体の「弾性成分」も温度により変化するし、フレキシブル基板２１とこれに接触する部材との摩擦係数も温度により変化するので、請求項３、４の場合において説明した「抵抗成分」も変化する。
【００８５】
請求項５記載の撮影装置では、図２に示すように、フレキシブル基板の温度を検出する温度検出手段２４を有し、この温度検出手段２４の検出出力により、制御情報の補正を行う。
【００８６】
即ち、記憶手段２３に「温度と弾性係数・摩擦係数の関係」等、温度変化に伴なう制御情報の補正に必要な情報を記憶させておく。温度検出手段２４の出力は図示されないＡ／Ｄコンバータを通じて演算手段９に取り込まれる。演算手段９は、温度検出手段２４からの温度情報と、記憶手段２３からの情報をもとに、温度変化に伴なうフレキシブル基板２１の物性特性の変化を考慮して、Ｘ、Ｙの各方向毎に異なる影響を補正して、撮像手段１３の変位駆動を行う。
【００８７】
このようにして、振れ補正への温度変化の影響を有効に軽減させ、良好な振れ補正が可能となる。
【００８８】
上に実施の形態を説明した撮影装置においては「振れ補正手段１１、１２により撮像手段１３を変位させる力が弾性力」である（請求項６）。
【００８９】
【発明の効果】
以上のように、この発明によれば、新規な撮影装置を実現できる。
【００９０】
この発明の撮影装置は、撮像素子が受光した画像の電気信号を画像処理部側へ取り込むためのフレキシブル基板が、撮像手段の変位駆動による振れ補正に与える影響を有効に軽減し、より制度のよい振れ補正を実効することが可能である。
【図面の簡単な説明】
【図１】発明の１実施形態である撮影装置（デジタルカメラ）の概略斜視図である。
【図２】図１の撮影装置における振れ補正関連機構を示す図である。
【図３】振れ補正手段を説明する図である。
【図４】フレキシブル基板の取り付け形態の１例を説明するための図である。
【図５】撮像手段１３の振れ補正動作における、フレキシブル基板の弾性成分の影響を説明する図である。
【図６】フレキシブル基板を弾性体による片持ち梁とみなした模型を説明するための図である。
【図７】フレキシブル基板２１の弾性成分を考慮した撮像手段変位駆動を説明するための図である。
【図８】フレキシブル基板２１の弾性成分を考慮した撮像手段変位駆動を説明するための模型を説明するための図である。
【図９】図８の模型による撮像手段の変位駆動を説明するための図である。
【図１０】フレキシブル基板の弾性成分を考慮した撮像手段の変位駆動を行うための圧電素子の駆動電圧波形と撮像手段の変位波形を説明するための図である。
【図１１】撮像手段の振れ補正動作に伴なうフレキシブル基板の抵抗成分を説明するための図である。
【図１２】圧電素子の駆動電圧波形に対する撮像手段の変位波形に、抵抗成分により発生する遅延を示す図である。
【図１３】抵抗成分による振れ補正の遅延の補正を説明するための図である。
【図１４】フレキシブル基板の形状および取り付け形態が、振れ補正に与える影響を説明するための図である。
【図１５】フレキシブル基板の形状および取り付け形態が、振れ補正に与える影響の例を説明するための図である。
【符号の説明】
１　　　撮影装置
２　　　撮影レンズ
３　　　撮影光学系
４　　　振れ検出センサ（Ｘ軸の回りの振れを検出）
５　　　振れ検出センサ（Ｙ軸の回りの振れを検出）
６　　　撮像素子
７　　　振れ検出センサ回路
８　　　振れ検出手段
９　　　演算手段
１０　　補正手段駆動回路
１１　　振れ補正手段（Ｘ軸の回りの振れの影響を補正）
１２　　振れ補正手段（Ｙ軸の回りの振れの影響を補正）
１３　　撮像手段
１４　　与圧ばね
１５１、１５２　　　圧電素子
１６１Ａ、１６１Ｂ、１６２Ａ、１６２Ｂ　　板ばね
１７１Ａ、１７１Ｂ、１７２Ａ、１７２Ｂ　　取り付け板
１８１、１８２　　ローラ
１９１、１９２　　押えねじ
２０１、２０２　ローラ
２１　　フレキシブル基板
２２　　ソケット
２３　　記憶手段
２４　　温度検出手段
２５　　シャッタボタン[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a photographing device such as a digital camera.
[0002]
[Prior art]
A photographing device that receives a subject image by a photographing optical system by an image pickup device of an image pickup unit and captures an electric signal of the image received by the image pickup device from the image pickup unit to the image processing unit side by a flexible substrate as a digital camera or the like Although it is known, in order to correct the "effect of shake (such as camera shake)" at the time of shooting, "shake" around two orthogonal axes orthogonal to the optical axis of the shooting optical system is detected by shake detection means. Then, based on the detected shake detection amount, the shake correction means displaces the imaging means in “two orthogonal directions corresponding to the direction of the shake” to reduce the relative displacement amount between the subject image and the imaging element. Is being done.
[0003]
Such “vibration correction” is repeated in a predetermined time period in each direction throughout the entire displacement operation of the image sensor during exposure.
[0004]
The degree of shake is detected with high accuracy by the shake detection means as the shake detection amount, and the displacement amount of the imaging means calculated based on it is also high accuracy, but it is not always sufficient in the correction operation actually executed. Accurate correction is not performed.
[0005]
As a result of repeated studies on this problem, the inventor has found that a flexible substrate that captures image signals from the imaging means to the image processing unit depends on its shape and mounting form for `` displacement drive of the image sensor '' for shake correction. Have a linear or non-linear effect.
[0006]
[Problems to be solved by the invention]
In view of the above-described circumstances, the present invention provides a method of controlling the vibration based on the amount of shake correction calculated based on the amount of shake detection, and also performing the control of correcting the mounting form of the flexible substrate or the influence of the mounting form and shape. It is an object to improve the effect of correction.
[0007]
[Means for Solving the Problems]
The image capturing apparatus according to the present invention may be configured to capture an image of a subject by an image capturing optical system by an image capturing device of an image capturing unit, and capture an electrical signal of the image received by the image capturing device from the image capturing unit to an image processing unit side by a flexible substrate to perform image capturing. An apparatus, wherein shake around two orthogonal axes orthogonal to the optical axis of the imaging optical system is detected by shake detection means, and based on the detected shake detection amount, the image pickup means is moved in the direction of shake by shake correction means. That is, it is displaced in two corresponding orthogonal directions to correct the influence of the shake. "
[0008]
In this specification, “shake” is representative of “camera shake” of a photographer, but is not limited to this, and the shake caused by an attached body when the imaging apparatus is attached to an automobile, an airplane, a remotely operated traveling body, or the like. And the like.
[0009]
The photographing apparatus according to claim 1, wherein the control information for displacing the imaging means, which is stored in the storage means, is made different in two directions orthogonal to each other according to the mounting form of the flexible substrate, and the two orthogonal directions are based on the control information. Correction ". “Two directions orthogonal to each other” are two directions in which the imaging unit is displaced.
[0010]
According to a second aspect of the present invention, in the image capturing apparatus according to the first aspect, "each of the control information is determined so as to correct the influence of a different elastic component in each of two directions orthogonal to each other depending on the mounting form of the flexible substrate." It is characterized by the following.
[0011]
According to a third aspect of the present invention, there is provided the image capturing apparatus according to the first aspect, wherein each of the control information is determined so as to correct the influence of a different resistance component in two directions orthogonal to each other by the mounting form of the flexible substrate. It is characterized by the following.
[0012]
The photographing apparatus according to claim 4, wherein "the control information stored in the storage means and displacing the imaging means is made different in two directions orthogonal to each other according to the shape and the mounting form of the flexible substrate, and based on these control information, Correction in two orthogonal directions ".
[0013]
The photographing apparatus according to any one of the first to fourth aspects can "have a temperature detecting means for detecting the temperature of the flexible substrate, and correct the control information by a detection output of the temperature detecting means." (Claim 5).
[0014]
In the photographing apparatus according to any one of the first to fifth aspects, the "force for displacing the imaging means by the shake correcting means" may be an elastic force (claim 6).
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the invention will be described.
[0016]
FIG. 1 illustrates an example of a photographing apparatus (digital camera).
Reference numeral 1 denotes a “photographing device”, reference numeral 2 denotes a “photographing lens”, reference numeral 3 denotes a “photographing optical system” including the photographing lens 2, and reference numeral 25 denotes a “shutter button”.
[0017]
When the X and Y axes are set as shown in FIG. 1, the subject image fluctuates in the Y direction (the direction in which the shutter button 25 is pressed down) with respect to the imaging means due to a shake around the X axis (due to hand shake or the like). Further, the subject image fluctuates in the X direction with respect to the imaging means depending on the shake around the Y axis. The “vibration correction” is an operation of displacing the imaging unit to make the relative fluctuation between the light receiving surface of the imaging element and the subject image close to zero.
[0018]
FIG. 2 is an explanatory diagram illustrating a portion of the imaging apparatus 1 that performs shake correction. Reference numerals 4 and 5 indicate a “vibration detection sensor”. The “imaging means” indicated by reference numeral 13 includes an imaging device 6 such as a CCD. The shake detection sensor 4 is a sensor for detecting “shake around the X axis” of the photographing device 1, and the shake detection sensor 5 is for detecting “shake around the Y axis” of the photographing device 1. It is a sensor.
[0019]
The detection amount of the shake detection sensors 4 and 5 is converted into a signal by the shake detection sensor circuit 7 to be a “shake detection amount”. The shake detection sensors 4 and 5 and the shake detection sensor circuit 7 constitute a shake detection means 8.
[0020]
The output of the shake detecting means 8 is sent to the calculating means 9. The calculating means 9 is composed of a microprocessor or the like, and performs a predetermined calculation based on the shake detection amount input from the shake detecting means 8 to calculate a "shake correction amount", and uses this as a signal to output a signal as a signal. Send to
[0021]
The correction unit driving circuit 10 drives the shake correction units 11 and 12 according to the input signal. The shake correcting unit 11 displaces the image sensor 6 in the “direction for reducing the shake around the X axis” in the Y direction. The shake correcting means 12 displaces the image sensor 6 in the X direction in a direction in which the shake around the Y axis is reduced. Such a series of shake correction operations are performed “repeatedly during exposure”.
[0022]
FIG. 3 is a diagram for explaining displacement of the image sensor 6 by the shake correction units 11 and 12.
The imaging means 13 holding the imaging element 6 is in contact with each spring surface of a hook-shaped pressurizing spring 14 via rollers 201 and 202 as shown in the figure.
The shake correcting means 11 includes a piezoelectric element 151 and mounting plates 171A and 171B fixed to both ends of the piezoelectric element 151 in the operation direction, two leaf springs 161A and 161B attached to the mounting plates 171A and 171B in a curved state, and a leaf spring 161A. And a roller 181 sandwiched between the central part of the leaf spring 161 and the imaging means 13 and a holding screw 191 for holding the central part of the leaf spring 161B.
[0023]
Similarly, the shake correction means 12 includes a piezoelectric element 152, mounting plates 172A and 172B fixed to both ends in the operation direction, two leaf springs 162A and 162B mounted to the mounting plates 172A and 172B in a curved state, It is composed of a roller 182 sandwiched between the central part of the leaf spring 162A and the imaging means 13, and a holding screw 192 for pressing the central part of the leaf spring 162B.
[0024]
When no “drive voltage” is applied to the piezoelectric element 151, the “upward force” applied from the holding screw 191 becomes the elastic force of the leaf springs 161 A and 161 B and acts upward on the image sensor 13. This upward force balances the downward force of the pressurizing spring 14. By adjusting the holding screw 191, the vertical position of the image sensor 13, that is, the position in the “Y-axis direction” can be adjusted.
[0025]
Similarly, when no drive voltage is applied to the piezoelectric element 152, the rightward force in the figure applied from the holding screw 192 becomes the elastic force of the leaf springs 162A and 162B, and acts rightward on the image sensor 13, This rightward force balances the leftward force of the pressurizing spring 14. By adjusting the holding screw 192, the position of the image sensor 13 in the left-right direction, that is, the position in the “X-axis direction” can be adjusted.
[0026]
By applying a “centering voltage” to the piezoelectric elements 151 and 152, the center of the light receiving surface of the imaging element 6 is positioned at the optical axis position of the imaging optical system.
[0027]
When a "positive drive voltage" is applied to the piezoelectric element 151, the piezoelectric element 15 extends in the operation direction (left-right direction in FIG. 3) from the centering state, and the leaf springs 161A and 161B are pulled at both ends to bend. The radius of curvature increases, and the interval between the leaf springs 161A and 161B increases.
[0028]
Since the leaf spring 161A is pressed by the holding screw 191, the deformation of the leaf springs 161A and 161B causes the imaging unit 13 to be displaced upward in FIG.
[0029]
When a "negative drive voltage" is applied to the piezoelectric element 151, the piezoelectric element 151 contracts in the operation direction (left-right direction in FIG. 3) from the centering state, and the radius of curvature of the leaf springs 161A and 161B decreases. The interval between the leaf springs 161A and 161B is reduced, and the image sensor 13 is displaced downward in FIG.
[0030]
The displacement of the imaging means 13 in the Y direction (the vertical direction in the figure) is smoothly performed by the rotation of the rollers 182 and 202.
[0031]
Similarly, when a “positive (negative) driving voltage” is applied to the piezoelectric element 152, the piezoelectric element 152 expands (shrinks) in the operation direction (vertical direction in FIG. 3), and the curvatures of the leaf springs 162A and 162B are curved. The radius increases (decreases), the interval between the leaf springs 162A and 162B expands (narrows), and the imaging element 13 opposes (pushes) the leftward force of the pressurizing spring 14 to the right (left) in FIG. Displace. The displacement of the imaging unit 13 in the X direction (the left-right direction in the figure) is smoothly performed by the rotation of the rollers 181 and 201.
[0032]
The amount of deformation of the piezoelectric element 151 in the operation direction is amplified 6 to 7 times by the leaf springs 161A and 161B, and the amount of deformation of the piezoelectric element 152 in the operation direction is amplified 6 to 7 times by the leaf springs 162A and 162B.
[0033]
FIG. 4 shows “an example of an attachment form” in which the flexible substrate 21 for “capturing an electric signal to the image processing apparatus (not shown)” is attached to the imaging unit 13. One end of the flexible board 21 is attached to the imaging means 13, and the other end is connected to the main body-side electronic board by the socket 22.
[0034]
FIG. 4A shows a state in which the imaging means 13 to which the flexible substrate 21 is attached is viewed from a direction orthogonal to the light receiving surface of the imaging device 6 which is a CCD (hereinafter referred to as “front direction”), and FIG. Indicates a state viewed from a direction parallel to the light receiving surface of the image sensor 6 (X direction in FIG. 4A, hereinafter referred to as “lateral direction”).
[0035]
FIGS. 4A and 4B show a state in which the “centering voltage” is applied to the piezoelectric elements 151 and 152 of the above-described shake correction units 11 and 12, and the imaging unit 13 is located at a center position with respect to the correction range. It is in. At this time, the “center position of the image sensor 6 (a position that matches the optical axis of the photographing optical system)” is defined as the origin position in the X and Y directions.
[0036]
When a drive voltage is applied to the piezoelectric elements 151 and 152 of the shake correction units 11 and 12, the expansion and contraction of the piezoelectric elements 151 and 152 (according to the drive voltage) are expanded by the leaf springs 161A, 161B, 162A and 162B, respectively. The imaging means 13 is displaced in the X and Y directions via the rollers 181, 182, 201 and 202.
[0037]
As shown in FIG. 5A, when the imaging means 13 is displaced in the X direction, the flexible substrate 21 is deformed as shown in the upper or lower drawing of FIG. Further, when the imaging means 13 is driven to be displaced in the Y direction, the “flexure state” of the flexible substrate 21 changes as shown in FIG. 5B.
[0038]
Such “deformation in the X direction” and “change in the bending state in the Y direction” of the flexible substrate 21 affect the driving operation of the imaging unit 13, that is, the shake correction operation.
As a result, the imaging unit 13 does not displace as in “control based on the shake correction amount calculated by performing a predetermined calculation based on the shake detection amount detected by the shake detection unit 8” and “the expected shake correction effect Cannot be obtained.
[0039]
Therefore, in the present invention, the control information for displacing the imaging element 6 is made different in two directions (X and Y directions) orthogonal to each other in accordance with the mounting form of the flexible board, and based on these control information, the two orthogonal directions are used. Make corrections.
[0040]
That is, the storage means 23 shown in FIG. 2 stores “control information that differs depending on the mounting form” of the flexible board 21, and the arithmetic means 9 uses the control information to store the control information for each driving direction (X direction, Y direction). Is performed to correct the different effects.
[0041]
The photographing apparatus described in the embodiment with reference to FIGS. 1 to 5 described above is described as “a subject image by the photographing optical system 3 is received by the image pickup device 6 of the image pickup unit 13, and an electric image of the image received by the image pickup device 6 is received. An imaging apparatus 1 for capturing an image by capturing a signal from an imaging unit 13 to a side of an image processing unit by a flexible substrate 21 and performing imaging around two orthogonal axes orthogonal to the optical axis of the imaging optical system 3. And correcting the influence of the shake by displacing the imaging means 13 in two orthogonal directions corresponding to the direction of the shake by the shake correcting means 11 and 12 based on the detected shake detection amount. The stored control information for displacing the imaging means 13 is made different in two directions orthogonal to each other in accordance with the mounting form of the flexible substrate 21, and correction in two orthogonal directions is performed based on the control information. Those (claim 1).
[0042]
As described above, in addition to the “control based on the shake correction amount” calculated by the predetermined calculation based on the shake detection amount detected by the shake detection unit 8, the driving direction of the imaging unit 13 is determined by the mounting mode of the flexible substrate 21. By performing control for correcting different effects for each case, it is possible to improve the effect of correcting the shake of a captured image.
[0043]
Consider a case where the image sensor 6 is driven to be displaced in the X direction as shown in FIG. The X direction in which the displacement drive is performed at this time is a direction parallel to the substrate surface of the flexible substrate 21 and orthogonal to the longitudinal direction.
[0044]
Since the flexible substrate 21 is fixed by the socket 22, if the flexible substrate is an “elastic body”, a plate-shaped cantilever having a length: l, a thickness: b, and a width: h shown in FIG. The beam can be considered, and can be considered in a simplified manner as shown in FIG.
[0045]
As shown in FIG. 6 (b), assuming a force: F at which the tip displacement of the cantilever becomes Δx for a neutral line in the width: h direction, the secondary moment of area: I of the deformation in this case is known. as,
I = bh ³ / 12 (1)
Therefore, the force: F and the displacement: Δx are related by E as an elastic coefficient determined by the material of the flexible substrate 21:
F = 3EI / (l ³ .DELTA.x) (2)
Satisfied.
[0046]
The elastic modulus E of the flexible substrate 21 is generally relatively small, but when considering the moment in the X direction, the value of the width h of the cantilever is large, and the second moment of area I is expressed by the following equation (1). Since the width is proportional to the cube of h, assuming that the entire elastic modulus of the cantilever system is k2,
k2 = 3EI / l ³ (3)
And the elastic coefficient: k2 is a relatively large value.
[0047]
Rewriting equation (2) using k2,
F = k2 · Δx (4)
It becomes. This is the “elastic component” when the flexible substrate 21 is considered as the above-mentioned cantilever.
[0048]
FIG. 7A shows the displacement of the imaging unit 13 by the shake correction unit 12 in the case where the elastic component (elastic force by k2: k2 · Δx) can be ignored. In this case, the displacement: Δx1 of the shake correction unit 12 becomes the displacement: Δx1 of the imaging unit 13 as it is.
[0049]
If the elastic component of the flexible substrate 21 cannot be neglected, the elastic component of the flexible substrate 21 acts as an elastic force in the direction opposite to the displacement direction of the imaging unit 13 as shown in FIG.
[0050]
As described with reference to FIG. 3, the shake correcting unit 12 for displacing the imaging unit 13 in the X direction elastically expands the deformation amount of the piezoelectric element 152 in the driving direction by the leaf springs 162A and 162B. Therefore, the shake correcting means 12 itself has an elastic component.
[0051]
For this reason, when the piezoelectric element 152 is driven so as to “realize the displacement: Δx1” without considering the elastic component of the flexible substrate 21, when the elastic component of the flexible substrate 21 cannot be ignored, the plate springs 162A and 162B Deformation is suppressed by the drag of the elastic component, and the actual displacement amount: Δx2 of the imaging unit 13 becomes smaller than “the displacement amount to be achieved: Δx1”, and the desired displacement amount: Δx1 cannot be realized.
[0052]
FIG. 8A is a model in which the elastic component of the shake correcting means 12 in FIG. 7B is modeled as a “spring having an elastic coefficient of k1”, and FIG. This is an equivalent model. The elastic coefficient k1 in FIG. 8 also includes the elastic component of the pressurized spring 4.
[0053]
Using the model of FIG. 8B, the “elastic component of elasticity: k2” of the flexible board 21 and the elastic component of elasticity: k1 of the shake correcting unit 12 are considered in “the X direction of the imaging unit 13 in the X direction. Displacement operation "will be considered.
[0054]
FIG. 9A illustrates a state in which the imaging unit 13 is at the “centering position”. At this time, the displacement of the flexible substrate 21 in the X direction is zero, and the force acting on the imaging unit 13 from the elastic component of the shake correction unit 12 is also zero. Since the elastic coefficient k1 of the vibration correcting means 12 includes the elastic components of the leaf springs 162A and 162B and the elastic component of the pressurized spring 14, the elastic forces of the leaf springs 162A and 162B and the pressurized spring 14 are balanced. State.
[0055]
FIG. 9B shows the displacement of the shake correcting means 12 by Δx1, the displacement of the imaging means 13 by Δx2, and the elasticity by the elastic coefficient k1 by applying the “positive drive voltage” from the centering voltage to the piezoelectric element 15. This shows a state in which the force and the elastic force by the elastic coefficient k2 are balanced. If the force at this time is "F",
F = k2 · Δx2 = k1 (Δx1−Δx2) (5)
Solving this for Δx2 gives
Δx2 = k1 / (k1 + k2) · Δx1 (6)
Therefore, Δx2 <Δx1.
[0056]
That is, when the elastic component of the flexible substrate 21 is considered, the “overall effective elastic coefficient” in the displacement of the imaging unit 13 in the X direction is “k1 / (k1 + k2)” according to the equation (6). When there is no influence of the flexible substrate 21, that is, when k2 = 0, Δx2 = Δx1, and as described above, the displacement: Δx2 of the imaging unit 13 is the same as the displacement: Δx1 of the shake correction unit 12.
[0057]
As shown in FIG. 9B, the voltage applied to the piezoelectric element 152 with respect to the displacement of the shake correction unit 12: Δx1 and the displacement of the imaging unit 13: Δx2 is set to V. Applied voltage: V is a voltage value relative to the centering voltage.
[0058]
Assuming that the “piezoelectric element drive voltage waveform” is a sine wave having an amplitude of V as shown by a curve A1 in FIG. 10A, the displacement of the imaging unit 13 is as shown by a curve B1 in FIG. Since the amplitude becomes Δx2, that is, a sine wave of k1 / (k1 + k2) · Δx1, the voltage becomes smaller than the voltage that realizes the sine wave of the maximum value: Δx1, which is the displacement of the imaging means 13 to be controlled. Cannot be realized, and the “accuracy of shake correction” is reduced.
[0059]
Therefore, by controlling the correction means driving circuit 10 so that the “piezoelectric element driving voltage waveform becomes the maximum value: V · (k1 + k2) / k1 sine wave” as shown by the curve A2 in FIG. As shown by a curve B2 in FIG. 10B, the amount of displacement of the image pickup means 13 can be set to "a sine wave of the maximum value to be controlled: Δx1", and the shake correction effect can be improved.
[0060]
Next, the case where the imaging unit 13 is driven to be displaced in the Y direction, which is the longitudinal direction of the flexible substrate 21 (the left-right direction in FIG. 5), will be considered.
As shown in FIG. 5 (b), when viewed from the lateral direction, the flexible board 21 is bent at the centering position in the Y direction (broken line), and is displaced in the Y direction. It changes as shown in the figure.
[0061]
As described above, the flexible substrate 21 viewed from the lateral direction can be considered as a "spring having a certain curvature". In this direction, the second moment of area: I is proportional to the cube of the thickness: b. Since b is very small, the elastic coefficient of the whole system is also very small, and therefore, the elastic component of the flexible substrate 21 hardly affects the displacement driving of the imaging means 13 in the Y direction.
[0062]
That is, in the displacement driving of the image sensor 13 in the Y direction, there is no problem only with the control based on the shake correction amount calculated by the predetermined calculation based on the shake detection amount detected by the shake detection sensor 8.
[0063]
That is, in the imaging device according to the second aspect, "each of the control information is determined so as to correct the influence of the different elastic components in two directions orthogonal to each other, depending on the mounting form of the flexible substrate 21".
[0064]
More specifically, based on the shake detection amount detected by the shake detection means 8, the shake correction amount calculated by a predetermined calculation is Δx in the X direction and Δy in the Y direction. At this time, the “product factor for the shake correction amount” is stored in the storage unit 23 of FIG. 2 as “control information”.
[0065]
The “product factor for the shake correction amount” is “1” for the shake correction amount: Δy, and “(k1 + k2) / k1” for the shake correction amount: Δx. Accordingly, the calculating means 9 multiplies the correction amounts: Δx and Δy calculated by the predetermined calculation based on the shake detection amount detected by the shake detecting means 8 by the product factor read from the storage means 23 to “Δx ( k1 + k2) / k1 ”and Δy · 1 are sent to the correction means driving circuit 10 as correction signals. Of course, the coefficients: k1 and k2 are determined experimentally.
[0066]
As described above, by controlling the influence of the different elastic components existing depending on the mounting form of the flexible substrate 21 for each driving direction of the imaging unit 13, the shake correction effect of the captured image can be improved.
[0067]
FIG. 11 shows another mode of attaching the flexible board 21 to the imaging means 13. One end of the flexible substrate 21 is fixed to the imaging unit 13, and the other end is inserted into the socket 22.
[0068]
When the displacement driving of the imaging unit 13 in the X direction is considered, the second moment of area: I is very large in proportion to the cube of the width h of the flexible substrate 21 as described above. Regarding the displacement drive in the direction, the flexible substrate 21 can be considered as a “rigid body”.
[0069]
Then, as the imaging means 13 is displaced in the X direction, the flexible substrate 21 rotates around the contact point C with the socket 22, for example, as shown in the upper part of FIG. At the contact portion between the substrate 21 and the socket 22, a "resistance component" is generated due to friction.
[0070]
Further, for example, if there is a contact portion between the flexible substrate 21 and the main body D of the photographing device as in “a portion indicated by reference numerals E1 and E2” in the lower diagram of FIG. , A resistance component is generated between the flexible substrate 21 and the main body D due to friction. Such a resistance component causes a delay in the driving operation of the imaging unit 13 by the shake correction units 11 and 12.
[0071]
When the piezoelectric element driving voltage waveform in the shake correcting units 11 and 12 is a “maximum value: V sine wave” as indicated by a curve H1 in FIG. The displacement of the curve 13 becomes “sine wave delayed from the piezoelectric element drive voltage waveform by Δt” as shown by the curve G1 in FIG.
[0072]
In such a case, as shown in FIG. 13A, “prediction calculation” of Δt is performed on the piezoelectric element driving waveform: H1, and the driving waveform is “a sine wave whose phase is shifted by Δt to the minus side. : H2 ". By driving the piezoelectric element 15 of the shake correcting means 11 or 12 with a sine wave: H2, a desired displacement operation of the imaging means 13 can be obtained as shown by a curve G2 in FIG. A curve G1 in FIG. 13B represents a displacement operation when displacement drive is performed without performing prediction calculation.
[0073]
Since the delay time Δt in the prediction calculation is different from the displacement direction: X, Y in the imaging means 13 in the frictional state related to the operation, the control is performed with a different delay time Δt depending on the displacement direction.
[0074]
That is, in the photographing apparatus according to the third aspect, each of the control information is determined so as to correct the influence of “a different resistance component in two directions (X, Y) orthogonal to each other” by the mounting form of the flexible substrate 21. . In the case described above, the control information is “delay time in prediction calculation: Δt”.
[0075]
Based on the shake detection amount detected by the shake detection unit 8, the calculation unit 9 calculates the shake correction amounts: Δx and Δy by a predetermined calculation. The storage unit 23 stores a delay time: Δtx for each of the X and Y2 directions. , Δty are “specified experimentally in advance” and stored.
[0076]
Then, the calculation means 9 performs a prediction calculation based on the delay times Δtx and Δty read from the storage means 23 and sends the result to the correction means drive circuit 10.
[0077]
As described above, by controlling the influence of the different resistance components in each of the displacement driving directions (X, Y directions) of the image pickup means for each driving direction of the image pickup means 13 depending on the mounting mode of the flexible substrate 21, the captured image can be displayed. The shake correction effect can be effectively improved.
[0078]
In FIG. 11, the displacement of the flexible substrate 21 is regarded as “rotation”, but the end of the flexible substrate on the imaging unit 13 side is fixed to a side edge parallel to the X direction of the imaging unit 13 over “width: h”. Therefore, as shown in FIG. 14, when the displacement driving of the imaging unit 13 in the X direction is considered, the portion of the flexible substrate 21 fixed to the imaging unit 13 is “translated, not rotated”. Therefore, in such a case, for example, a tensile stress is generated in the portion P and a compressive stress is generated in the portion Q of the flexible substrate 21. In addition, a torsional component is generated in the flexible substrate 21 due to a change in the shape of the flexible substrate 21, and, for example, as shown in the lower diagram of FIG. Part shown).
[0079]
Furthermore, due to the "play" of the contact portion between the flexible substrate 21 and the socket 22, the change in the contact area due to the displacement / deformation of the flexible substrate 21 is not uniform, and the flexible substrate 21 is subjected to frictional force via frictional force. The acting resistance component changes, or some kind of vibration occurs in the flexible substrate 21 itself.
[0080]
Such “various phenomena occurring in the flexible substrate 21” affects the displacement driving of the imaging unit 13, and for example, as shown in FIG. 15A, “the change in displacement with respect to the voltage is not linearly proportional”. As shown in FIG. 15B, “the change in the displacement with respect to the voltage becomes a hysteresis”, or, for example, the above-described delay time: Δt changes according to the moving speed of the imaging unit 13.
[0081]
Such an effect is a characteristic related to the mounting form of the flexible substrate 21 and the shape of the flexible substrate 21, and differs depending on the displacement direction (X, Y directions) of the imaging unit 13. Therefore, the control factors for each of these directions are stored in the storage unit 23 as “control information”, and the control unit 9 controls the control factors based on the “vibration detection amount” detected by the vibration detection unit 8. The “vibration correction amount” is calculated, and the correction amount is adjusted by the control factor read from the storage unit 23 to generate a signal to be applied to the correction unit driving circuit 10.
[0082]
That is, in the photographing apparatus according to the fourth aspect, the subject image by the photographing optical system 3 is received by the image pickup device 6 of the image pickup device 13, and the electric signal of the image received by the image pickup device 13 is received from the image pickup device 13 by the flexible substrate 21. An image capturing apparatus that captures an image by taking it into a processing unit side, wherein a shake around two orthogonal axes orthogonal to an optical axis of the image capturing optical system 3 is detected by a shake detection unit 8 and based on a detected shake detection amount. In the apparatus for correcting the influence of the shake by displacing the imaging means 13 in two orthogonal directions corresponding to the directions of the shakes by the shake correction means 11 and 12, the control information stored in the storage means 23 and displacing the imaging means ( The above control factors are made different in two directions orthogonal to each other according to the “shape and mounting form” of the flexible substrate 21, and correction in the two orthogonal directions is performed based on the control information. Cormorant.
[0083]
In this way, by controlling the influence on the shake correction related to the mounting form and the shape of the flexible substrate for each driving direction of the imaging unit 13, the shake correction effect of the captured image can be improved.
[0084]
The above-described “elastic coefficient of the flexible substrate 21: E” is not invariant with a temperature change, but changes with a temperature change. Therefore, the second moment of area: I expressed by the equation (1) also changes due to the temperature change, and in the case of the above-described claims 2 and 4, the driving of the imaging means 13 in the X direction is performed. The "elastic component" of the entire system in consideration of the temperature changes with the temperature, and the coefficient of friction between the flexible substrate 21 and a member in contact with the flexible substrate also changes with the temperature. The components also change.
[0085]
As shown in FIG. 2, the photographing apparatus according to the fifth aspect has a temperature detecting means 24 for detecting the temperature of the flexible substrate, and the control information is corrected based on the detection output of the temperature detecting means 24.
[0086]
That is, information necessary for correcting control information accompanying a temperature change, such as “relationship between temperature and elastic coefficient / friction coefficient”, is stored in the storage unit 23. The output of the temperature detecting means 24 is taken into the calculating means 9 through an A / D converter (not shown). The calculating means 9 calculates each of X and Y on the basis of the temperature information from the temperature detecting means 24 and the information from the storage means 23, taking into account the change in the physical properties of the flexible substrate 21 accompanying the temperature change. The displacement driving of the imaging unit 13 is performed by correcting the influence different for each direction.
[0087]
In this manner, the effect of the temperature change on the shake correction is effectively reduced, and good shake correction can be performed.
[0088]
In the photographing apparatus described in the above embodiment, "the force for displacing the imaging means 13 by the shake correction means 11 and 12 is an elastic force" (claim 6).
[0089]
【The invention's effect】
As described above, according to the present invention, a novel photographing device can be realized.
[0090]
According to the photographing apparatus of the present invention, the flexible substrate for capturing the electric signal of the image received by the image pickup device to the image processing unit side effectively reduces the influence on the shake correction due to the displacement drive of the image pickup means, and is more accurate. It is possible to perform shake correction.
[Brief description of the drawings]
FIG. 1 is a schematic perspective view of a photographing apparatus (digital camera) according to an embodiment of the present invention.
FIG. 2 is a diagram showing a shake correction related mechanism in the photographing apparatus of FIG. 1;
FIG. 3 is a diagram illustrating a shake correction unit.
FIG. 4 is a diagram for explaining an example of a mounting mode of a flexible substrate.
FIG. 5 is a diagram for explaining the influence of the elastic component of the flexible substrate on the shake correction operation of the imaging unit 13;
FIG. 6 is a view for explaining a model in which the flexible substrate is regarded as a cantilever made of an elastic body.
FIG. 7 is a diagram for explaining displacement driving of an imaging unit in consideration of an elastic component of a flexible substrate 21;
FIG. 8 is a view for explaining a model for explaining the displacement driving of the imaging means in consideration of the elastic component of the flexible substrate 21;
FIG. 9 is a diagram for explaining displacement driving of the imaging means by the model of FIG. 8;
FIG. 10 is a diagram for explaining a drive voltage waveform of the piezoelectric element and a displacement waveform of the imaging unit for performing displacement driving of the imaging unit in consideration of an elastic component of the flexible substrate.
FIG. 11 is a diagram for explaining a resistance component of a flexible substrate accompanying a shake correction operation of an imaging unit.
FIG. 12 is a diagram illustrating a delay caused by a resistance component in a displacement waveform of an imaging unit with respect to a drive voltage waveform of a piezoelectric element.
FIG. 13 is a diagram for explaining correction of a shake correction delay due to a resistance component.
FIG. 14 is a diagram for explaining an influence of a shape and a mounting form of a flexible substrate on shake correction.
FIG. 15 is a diagram for explaining an example of an influence of a shape and a mounting form of a flexible substrate on shake correction.
[Explanation of symbols]
1 Photographing device
2 Shooting lens
3 Shooting optical system
4 Runout detection sensor (detects runout around X axis)
5 Runout detection sensor (detects runout around Y axis)
6 Image sensor
7 Runout detection sensor circuit
8 Shake detection means
9 Calculation means
10 Correction means drive circuit
11 Shake correction means (corrects the effect of shake around the X axis)
12 Shake correction means (corrects the effect of shake around the Y axis)
13 Imaging means
14 Pressurized spring
151, 152 Piezoelectric element
161A, 161B, 162A, 162B Leaf spring
171A, 171B, 172A, 172B Mounting plate
181 and 182 rollers
191, 192 Holding screw
201, 202 roller
21 Flexible board
22 socket
23 storage means
24 Temperature detection means
25 Shutter button

Claims

A photographing apparatus that receives a subject image by a photographing optical system by an image pickup device of an image pickup unit, and captures an electric signal of the image received by the image pickup device from the image pickup unit to the image processing unit side by a flexible substrate to perform photographing,
Shake around two orthogonal axes orthogonal to the optical axis of the photographing optical system is detected by shake detecting means, and based on the detected shake detection amount, the image correcting means corresponds to the direction of shake based on the detected shake detection amount. In the one that is displaced in two orthogonal directions to correct the influence of the above-mentioned vibration,
The control information that is stored in the storage means and displaces the imaging means is made different in two directions orthogonal to each other in accordance with the mounting mode of the flexible substrate, and the correction in the two orthogonal directions is performed based on the control information. Characteristic imaging device.

The photographing apparatus according to claim 1,
An imaging apparatus, wherein each control information is determined so as to correct the influence of a different elastic component in two directions orthogonal to each other depending on a mounting mode of a flexible substrate.

The photographing apparatus according to claim 1,
An imaging apparatus, wherein each control information is determined so as to correct the effects of different resistance components in two directions orthogonal to each other, depending on a mounting form of a flexible substrate.

A photographing apparatus that receives a subject image by a photographing optical system by an image pickup device of an image pickup unit, and captures an electric signal of the image received by the image pickup device from the image pickup unit to the image processing unit side by a flexible substrate to perform photographing,
Shake around two orthogonal axes orthogonal to the optical axis of the photographing optical system is detected by shake detecting means, and based on the detected shake detection amount, the image correcting means corresponds to the direction of shake based on the detected shake detection amount. In the one that is displaced in two orthogonal directions to correct the influence of the above-mentioned vibration,
The control information for displacing the imaging means, which is stored in the storage means, is made different in two directions orthogonal to each other according to the shape and the mounting form of the flexible substrate, and the correction in the two orthogonal directions is performed based on the control information. An imaging device characterized by the above-mentioned.

The photographing apparatus according to any one of claims 1 to 4,
An imaging apparatus, comprising: temperature detection means for detecting a temperature of a flexible substrate, wherein control information is corrected based on a detection output of the temperature detection means.

The photographing apparatus according to any one of claims 1 to 5,
An imaging apparatus, wherein the force for displacing the imaging means by the shake correction means is an elastic force.