JP3716999B2 - Vehicle camera - Google Patents

Description

が成立するものとした。
【００２６】
請求項９に記載の発明は、同じく反射面間の好ましい角度を規定したもので、撮影手段の画角をθ０、反射面の各面の法線のなす角度を２・θｍとして、
４５゜−θ０／４≦θｍ≦５０゜−θ０／４
が成立するものとした。
【００２７】
【作用】
請求項１のものでは、車両前方側の端で連結したＶ字型ミラーの２つの反射面を撮影範囲として撮影手段がＶ字型の頂点側から撮影する。撮影手段は車両前進方向とは逆の後方を向いて撮影するから、撮影した画像は車両から見た左方向が右側に、右方向が左側になるとともに、ミラーによるその反射虚像はそれぞれ左右反転している。この撮影画像が信号処理手段によって一括左右反転されると、車両から見た左方向は出力画面の左側に、右方向は出力画面の右側に替わるとともに、それぞれ正転画像となる。
【００２８】
２つの反射面を、車両を幅方向に２分する中心面に平行な面に対して略対称に配置すると、右側左側とも、撮影する範囲が最大限に広く確保される。
また、光学系の光軸を略水平とし、反射面の上下略中央を通るように配置すると、水平方向を中心に上下が均等に撮影され、安全確認する領域が容易確実に撮影視野に入る。
撮影手段とミラーをケースに格納し、撮影手段が窓を介してケース外部を撮影するように構成すると、車体外部の悪環境に設置しても保守管理が容易である。
【００２９】
また、請求項７、８および９のものは、それぞれ反射面と光学系の距離、反射面の水平方向の長さ、反射面の角度を規定することによって反射面が無駄なく撮影手段の撮影範囲に入り、全体がコンパクトに構成される。
【００３０】
【実施例】
以下、この発明を図面に基づいて説明する。
図１は発明の第１の実施例を示すカメラ装置の外観斜視、図２はその水平断面図であり、図３は車両前端部に取り付けた状態を示す斜視図である。
ボックス状のケース２内にＣＣＤカメラ本体１０がそのレンズ筐体１１に形成された光学系を後方（車両側）に向けて設けられている。ＣＣＤカメラ本体１０は光学系のほか２次元イメージセンサとしてＣＣＤ素子１２を備え、回路基板１３に信号処理回路１４ならびに電源回路１５等が内蔵され、動画像を撮影して映像信号としてのコンポジットビデオ信号を出力する。そして信号処理回路１４は、一般の市販カメラに多く用いられている例えば図２８に示したのと同構成により画面全体を一括して左右反転する機能を備えている。
【００３１】
ＣＣＤカメラ本体１０の後方にはその光学系に対向して平面の反射面２１、２２を外側に向けたＶ字型ミラー２０が配置してある。
ケース２は防水構造とされ、その側壁２ａの反射面２１、２２に対応する部位には、透明体４を備える窓３が設けられている。透明体４としては、アクリル、ポリカーボネイト等の高透過率透明樹脂や、ガラス等が用いられる。この窓３を通してＣＣＤカメラ本体１０はケース２外部を撮影し、図２中、視線方向ｕ１、ｕ２で挟まれる範囲、ｖ１、ｖ２で挟まれる範囲が撮影範囲となる。
【００３２】
ケース２内にユニット化されたこのカメラ装置１は、図３に示すように、車両Ｓの中心面（車両を幅方向に２分する面）上、最先端付近に取り付けられている。
この際、水平線がモニタ画面上で横線となるように、ＣＣＤカメラ本体１０の光学系の光軸が水平面と平行に、そして反射面２１、２２の法線が水平面と平行になるように姿勢を決定して設置してある。換言すれば、ＣＣＤカメラ本体１０と反射面が水平面に対し面対称となっており、これにより、水平方向を中心に上下が均等に撮影される。
【００３３】
また、カメラ装置１で撮影した映像は、図４のようにダッシュボードＫ上に設置された、例えばＬＣＤなどで構成されるモニタ８に表示される。
カメラ装置１とモニタ８の間には、図５に示すように、切り替えスイッチ６を設けてモニタ８への映像の出力を運転者による手動切り替えでＯＮ／ＯＦＦできるようになっている。
【００３４】
ここで、本カメラ装置１の仕様について具体的な数値を求めてみる。
ＣＣＤカメラ本体１０と反射面２１、２２の左右方向のオフセット量、およびＣＣＤカメラ本体と反射面の各傾斜角によって撮影範囲が変化するが、この実施例では撮影範囲を左右対称とし、画面の比率を１：１としてある。
図６およびこれを線図化した図７を参照して、ＣＣＤカメラ本体１０の水平方向の撮影画角をθ０、反射面２１、２２の各面の法線のなす角度を２・θｍ、ＣＣＤカメラ本体のレンズ（レンズ筐体１１先端）と反射面２１、２２との間の距離をｄ、１枚の反射面の水平方向の長さをＬとして、これらの充たすべき条件を求める。なお、図７中、（ｂ）、（ｃ）、（ｄ）は（ａ）の部分詳細を示す。
【００３５】
まず、車幅方向と撮影範囲の後端方向との間の角度をθｒとしたとき、θｒは車体の映り込みと映像の有効性とを考慮すると、
０°≦θｒ≦１０°
であることが望ましい。
このとき、反射面２１、２２の各面の法線のなす角度２・θｍは、図７の（ｃ）の三角形ＥＣＤにおいて、
９０°＋θ０／２＋｛θｍ＋（θｍ−θｒ）｝＝１８０°
すなわち、
θｍ＝４５°−θ０／４＋θｒ／２
の関係を持つことから、
４５°−θ０／４≦θｍ≦５０°−θ０／４
を充たさなくてはならない。
【００３６】
レンズ筐体１１の外形の半径をＲとすると、レンズ筐体１１が反射虚像に映り込まないためには、レンズと反射面との間の距離ｄは、図７の（ｂ）において、
ｄ≧Ｒ・ｔａｎ（９０°−２・θｍ）
を充たさなくてはならない。
ｄが大きくなると反射面２１、２２もまた大きくする必要が生じ、カメラ装置１の大型化につながる。また、取付け公差として２ｍｍ程度必要とする。これらから、
Ｒ・ｔａｎ（９０°−２・θｍ）
≦ｄ≦Ｒ・ｔａｎ（９０°−２・θｍ）＋２
という条件が得られる。
【００３７】
続いて、ＣＣＤカメラ本体１０の画角をθ０、光学系の入射瞳の半径をｒとしたとき、ＣＣＤカメラ本体の全視野が反射面２１、２２を撮影し、かつ、このＶ字型ミラー２０を出来得る限り小型にするために、図７の（ｄ）の四角形ＡＣＤＢにおける、
ｈ’＝Ｌ・ｓｉｎθｍ
ｈ”＝Ｌ・ｃｏｓθｍ−ｒ
ｈ”／（ｈ’＋ｄ）＝ｔａｎ（θ０／２）
の関係から、
【数３】

とすればよい。
【００３８】
ここで、ＣＣＤカメラ本体１０の諸元を、水平方向の画角がθ０＝６０°、レンズ筐体１１の半径Ｒ＝７．０ｍｍ、光学系入射瞳ｒ＝２．０ｍｍとして、装置の真横方向から前方にかけての範囲（すなわち、θｒ＝０°）を撮影するものとする。
このとき、
θｍ＝３０°
４．０４≦ｄ≦６．０４ （ｍｍ）
となる。
【００３９】
これより、ｄ＝５ｍｍとすれば、
【数４】

となる。
さらに、ＣＣＤカメラ本体の回路基板１３の縦×横×厚さのサイズを３０×３０×５（ｍｍ）とし、レンズ筐体１１の長さを２０ｍｍとすると、必要なユニットの寸法は、
長さ：５＋２０＋５＋１０．５×ｓｉｎ（３０°）＝３５．２５（ｍｍ）
また、幅は反射面が、
２・Ｌ・ｓｉｎ（３０°）＝１０．５（ｍｍ）
となり、回路基板１３の大きさに依存する。ここでは、幅：３０ｍｍとする。
【００４０】
反射面２１、２２の高さはＣＣＤカメラ本体の視野の幅対高さの比を４：３として、
１０．５×３／４＝７．９（ｍｍ）
となり、これも回路基板の大きさに依存する。ここでは、高さ：３０ｍｍとする。
【００４１】
以上をまとめると寸法諸元は図８に示されるようなものとなり、ケース２を考慮するとユニットの必要最小サイズは、
長さ×幅×高さ＝４０×３０×３０（ｍｍ）
程度となる。
ＣＣＤカメラ本体の回路基板１３は実際には信号処理回路１４、電源回路１５などのために、もう１枚程度必要となるが、レンズ筐体１１の下部などのスペースに充分収容可能である。
【００４２】
次に作用を説明する。
図９の（ａ）で示すように、ＣＣＤカメラ本体１０で、図示省略した窓を通り反射面２１、２２を経由した反射虚像を撮影する。すると、ＣＣＤカメラ本体１０が撮影する映像は、（ｂ）のように、画像の右半面が車両前部左方の反転画像ＧＨＬとなり、左半面が車両前部右方の反転画像ＧＨＬとなる。
この画像が、ＣＣＤカメラ本体１０に内蔵された信号処理回路１４により画面全体を一括して左右反転される。
左右一括反転すれば、各方向の画面の補正ができる。この結果、（ｃ）に示すように、右、左半面にそれぞれ右方、左方の視界を提示する正転画像ＧＲ、ＧＬが得られる。この映像出力がモニタ８に送られそのまま表示される。
【００４３】
以上のようにこの実施例によれば、ＣＣＤカメラ本体１０を後方に向けるとともに、そのレンズに対向して反射面を外側に向けたＶ字型ミラー２０を配置して車両の左右を撮影し、ＣＣＤカメラ本体の信号処理回路１４により画面全体を一括左右反転した映像信号をモニタ８に送出して表示するものとしたので、複雑高価な追加のコントローラなどを要しないで正転画像をモニタ８に表示することができる。
【００４４】
これにより、セダン等フードのある車両の走行中において両側が塀や建物等で左右の見通しの悪い路地から本道に出るときなどに、図１０に示されるように、車両Ｓの先端が本道に突き出さない位置で左右両方向が同時に撮影され、その撮影視野ＲＳが運転者自身の眼からは死角となる領域Ｑをカバーして、そのモニタ表示によって本道等の交通状況（自動車や自転車、歩行者がいるか等）の確認を行うことができる。
【００４５】
そして、撮影範囲を左右対称とすることにより、実際に運転者がモニタ画像を見たときにどこが写っているのかの判断が容易である。
同じく、ＣＣＤカメラ本体１０の光軸系統が水平方向を中心に上下を均等に撮影する方向に設置されているから、安全確認する領域が容易確実に撮影視野に入る。さらに、画面の左右分割比を１：１としてあるので、右側左側とも、撮影する範囲が最大限に広く確保され、確認がしやすい。
【００４６】
また、カメラ装置１は車両Ｓの最先端で巾中心面上に取り付けられているから、車両の交差点への進入角度の影響を最も受けにくく、交差点への進入角度が変わっても車両の最も先端付近の位置を確保できる利点がある。
【００４７】
なお、上記実施例では、ＣＣＤカメラ本体１０に対して反射面２１、２２の位置関係が上下左右ともに面対称としてあるが、これに限定されない。 すなわち、ＣＣＤカメラ本体とＶ字型ミラーの位置関係には、相互間のオフセット量、相互間の各傾斜角に自由度があり、これらにより撮影範囲等が変化可能である。
ＣＣＤカメラ本体１０と反射面２１、２２のオフセット量が変わった場合、Ｖ字型ミラーの各反射面にできる反射虚像の撮影画面に占める割合が変化する。ＣＣＤカメラ本体、あるいは２つの反射面の少なくともいずれかの傾斜角が変わると、反射面に映り込む角度範囲が変化する。したがって、必要に応じて左右方向の撮影範囲だけではなく、上下方向の撮影範囲も任意に変えることができる。
【００４８】
また、実施例ではカメラ装置１が車両Ｓの巾中心面上に取り付けられているが、通常運転席は車両の中心から横にオフセットしているので、右ハンドル車であれば図１１のように、右側の運転者の正面前方に設置することもできる。これによれば、被写体（他の車両等）までの距離が実際に運転者自身で見た場合と近くなり、被写体の遠近感をより把握しやすくなる。
【００４９】
その他、カメラ装置１の車体への設置部位としては、ボンネットＳＢ上やバンパーＢＰ下部など運転席より前方の任意の点が選択できる。
なおまた、実施例ではカメラ装置１とモニタ８の間を手動切り替えの切り替えスイッチ６で接続したが、このほか、車速等に応じて作動する自動切り替えスイッチなども設けることができる。
【００５０】
また、カメラ装置１の撮影手段としてＣＣＤカメラ本体１０のかわりに、撮像管等も使用できる。そして、Ｖ字型ミラーの反射面には平面反射板を用いたが、かわりに曲面を連結した反射面であってもよい。例えば凸面鏡とすれば画角が広がる。
なお、モニタ８は専用のものに限らず、テレビジョン受信機用のモニタやナビゲーション用のモニタなどを必要時のみ流用することができる。
【００５１】
図１２は本発明の第２の実施例を示す。この実施例は、１台のモニタに左右両方向の撮影画面を上下に分割して表示するようにしたものである。
図の（ａ）はケース２Ａの上壁を取り除いて内部を示す上面図、（ｂ）はＣＣＤカメラ本体３０側の端壁２Ａｂを取り除いて内部を示す背面図、（ｃ）は側壁２Ａａを取り除いて内部を示す側面図である。
カメラ装置１Ａは、ボックス状のケース２Ａ内に、２次元イメージセンサとしてＣＣＤ素子３２を有するＣＣＤカメラ本体３０がそのレンズ筐体３１に形成された光学系を前方（車両進行方向）に向けて設けられている。
【００５２】
ＣＣＤカメラ本体３０は上記レンズ筐体３１およびＣＣＤ素子３２のほか、信号処理回路を含む回路基板３３を有している。電源として乗用車の場合ＤＣ１２Ｖを加えると、動画像を撮影して映像信号としてのコンポジットビデオ信号を出力する。そして信号処理回路は一般の市販カメラに多く用いられる画面全体を一括して左右反転する機能を備えている。
【００５３】
ＣＣＤカメラ本体３０の前方にはそのレンズ筐体３１に対向して平面の反射面４１、４２を備えるミラー４０が光軸Ｐに軸対称に配置してある。
ケース２Ａは防水構造とされ、その側壁２Ａａのミラー４０の反射面に対応する部位には、透明体４Ａを備える窓３Ａが設けられている。この窓３Ａを通してＣＣＤカメラ本体３０はケース２Ａ外部を撮影する。透明体４Ａとしては、前実施例の透明体４と同じく、アクリル、ポリカーボネイト等の高透過率透明樹脂や、ガラス等が用いられる。
なお、図中、ミラー４０については白色面が反射面、ハッチング面が非反射面を示している。他の図においても同様である。
【００５４】
ケース２Ａにユニット化された上記カメラ装置１Ａは、第１の実施例と同様に、車両巾中心上のバンパーＢＰの上（グリルの前）や、あるいはナンバープレートの後側等に設置されるが、ＣＣＤカメラ本体３０の光軸が車両の前後方向に一致し、かつ、上述のように前向きに、かつ、水平に取付けられる。
【００５５】
光学系は左右方向（＝水平方向）に約４５°の画角を有する。画角はレンズの焦点距離ｆとＣＣＤのサイズにより決まる。例えば１／３インチ（４．８×３．６ｍｍ）のＣＣＤ素子を使用する場合には、ｆ＝５．８ｍｍとすればよい。
また、図１３に示すように、ＣＣＤ素子３２の受光面３２ａ上には、上下２つの窓４８ＵＰ、４８ＬＷが横方向に若干量オフセットするマスク４７が貼り付けられている。
【００５６】
ケース２Ａに対してＣＣＤカメラ本体３０とミラー４０の位置関係は、図１４に示すように、（ａ）のようにレイアウトされたものをＣＣＤカメラ本体３０の光軸Ｐを中心にして回転させて（ｂ）としたものである。図は、レンズ筐体３１、ＣＣＤ素子３２、ミラー４０を抜き出し、三角法で示している。
まず、（ａ）において、レイアウトはＣＣＤカメラ本体３０の左右方向と水平面とが一致し、レンズ筐体３１の光軸が水平となっている。
【００５７】
ミラー４０の２枚の反射面４１、４２は、レンズ筐体３１の光軸Ｐを含む水平面で分離され、右側を向いた反射面４１は光軸を含む水平線より上方にのみ存在し、左側を向いた反射面４２は光軸を含む水平線より下方にのみ存在する。
この２枚の反射面４１、４２で、ＣＣＤカメラ本体３０の撮影画角を全て覆うようにミラー４０のサイズを決定する。
【００５８】
ミラーの角度は、ＣＣＤカメラ本体３０の画角や撮影する範囲により変える必要があるが、ここでは、レンズ筐体３１の光軸と反射面の法線のなす角度を左右とも５６．３°とした。
（ｂ）のレイアウトは上記（ａ）におけるＣＣＤカメラ本体３０およびミラー４０を、同時にレンズ筐体３１の光軸を中心にθ＝８．６°回転させたものである。このθの値は、上下方向の画角３４．５°の１／４である。
【００５９】
次に作用を説明する。
まず、ＣＣＤカメラ本体３０は窓を通してミラーの２枚の反射面に反射した虚像を撮影することにより、ケース２Ａ外部の左右両方向を同時に撮影する。
ＣＣＤカメラ本体３０とミラー４０は光軸中心に同じ角度だけ回転傾斜されているため、図１５の（ａ）のように、撮影画面上でミラーの反射面４１、４２の境界は水平となり、右方向、左方向の撮影画面ＧＡＨＲ、ＧＡＨＬは上下に分割される。
【００６０】
また、ＣＣＤカメラ本体３０とミラー４０の両方を同じだけ回転させているため、上半分の画面（図示した例では右側の側方を撮影した画面）内では、水平を中心に上下均分に撮影されている。同様に、下半分の画面（図示した例では左側の側方を撮影した画面）内でも水平を中心に上下均分に撮影されている。
ここでは、上下に２分割し、左右方向を撮影しているため、左右独立した反転は必要なく、撮影された画像はＣＣＤカメラ本体の信号処理回路で左右一括反転されて、図１５の（ｂ）のような正転画像ＧＡＲ、ＧＡＬが得られる。
こうしてＣＣＤカメラ本体３０で撮影した画像のモニタ表示例が図１６に示される。
【００６１】
レンズ筐体３１の光学系の光軸とミラー４０の各反射面の法線のなす角度を２枚とも５６．３°とするとき、ミラー４０を介してＣＣＤカメラ本体３０で撮影される範囲は車両の真横から４５°であるが、マスクにより画角が減少して約４０°となる。
ＣＣＤ素子３２の受光面３２ａ上に貼り付けたマスク４７のため、モニタに出力される画面には上半分の右側方の撮影画面ＧＡＲ内には左端に、下半分の左側方の撮影画面ＧＡＬ内には右端に、それぞれ黒色表示された指標ブロックＢＫができる。これにより、上半分が右側、下半分が左側の画像であることの認識性を高めている。
【００６２】
ここで、本実施例の作用について理解を容易にするため、ＣＣＤカメラ本体８０の光軸まわりにミラー８３、８４を回転させない上下分割方式を比較例として説明する。
比較例を図１７に示す。（ａ）のレイアウトは図１４の（ａ）とほぼ同じである。このレイアウトでは、出力画面をモニタで見ると右側の画面が上半分に、左側の画面が下半分に映しだされる。しかし、上半分を占める右側の画面は水平方向より上方のみを示し、下半分を占める左側の画面は水平方向より下方のみを示してしまう。
【００６３】
これはミラー８３、８４が水平面に垂直に設置してあるためである。そこで、上半分の画面に水平方向より下方の部分も映し出し、下半分の画面に水平方向より上方の部分も映し出すために、上側のミラー８３を下方Ｄ方向に、下側のミラー８４を上方Ｕ方向に傾斜させたものが、図の（ｂ）のレイアウトである。
これにより、上側のミラー８３であっても水平面を中心とした上下両方向を見ることができる。
【００６４】
ところが、ミラーを傾斜させたため、図１８のように、それぞれのミラーにもう片方のミラーが映り込むという問題が生じる。すなわち、光軸を含む水平面で分離されているそれぞれのミラーを傾斜させ、光軸を含む水平面よりも反対側を撮影するから、図１９のように、カメラ視線Ｘのうちそれぞれのミラー８３、８４が交差している点より内側の部分で視線ＸＳの光路が相手方ミラーの一部で遮断され、視野が狭まり、かわりにお互いが映り込んでしまうわけである。
これに対して、本実施例では、ミラー４０の傾斜とともにＣＣＤカメラ本体３０も同時に回転させている。すなわち、ミラーのそれぞれの反射面がお互いに映り込まない状態のままで、回転させているものである。
【００６５】
本実施例は以上のように構成され、ＣＣＤカメラ本体３０の前方に２つの反射面を水平面で分離したミラー４０を配置するとともに、ＣＣＤカメラ本体３０とミラー４０の両方を同じだけ回転させたレイアウトとしたので、上下それぞれの画面で水平を中心に上下均分に撮影される。
この場合に、第１の実施例と同じく、複雑高価な追加のコントローラなどを要しないで正転画像をモニタに表示することができ、見通しの悪い路地から本道に出るときなどに、交通状況の確認を行うことができる。
【００６６】
そして、同一形状の反射面を光軸に軸対称に設けることにより、実際に運転者がモニタ画像を見たときにどこが写っているのかの判断が容易であり、しかもＣＣＤ素子の受光面にマスキングを行ない、上下の画面の対照的な部位に黒色表示の指標ブロックが提示されるものとしたので、認識性が高い。
他方、同じくＣＣＤカメラ本体とミラーの両方を同じだけ回転させているので、双方のミラーの映り込みがなく、広い視野が確保される。
【００６７】
また、カメラ装置１Ａは車両の最先端で巾中心面上に取り付けられているから、車両の交差点への進入角度の影響を最も受けにくく、交差点への進入角度が変わっても車両の最も先端付近の位置を確保できる利点がある。
また、各方向の画面ＧＡＲ、ＧＡＬを横長としているため、同じ倍率のままで左右方向（水平方向）の画角を広くとることが可能であるという効果を有する。
【００６８】
なお、本実施例では、光軸まわりの回転前の状態で、ミラー４０を左右対称としてどこが写っているのかについて誤解の可能性を少なくしているが、慣れればその可能性は低減するのでこれに限定されない。ミラーの角度を変えることにより撮影する範囲が変化するから、求める視野の広さに応じてそれぞれを設定し左右で異ならせることができる。
【００６９】
また前実施例と同じく、ミラー４０の反射面を凸面とすれば、画角を広角化できる。
さらに、本実施例では光軸まわりの回転角度θをＣＣＤカメラ本体３０の上下方向の画角の１／４として、撮影範囲が水平方向を中心に上下均等になるようにしたが、運転者の好みで水平よりやや上側を中心に見えるようにしたいときに回転角度を小さく、水平よりやや下側を中心に見えるようにしたいときに回転角度を大きくすればよい。
【００７０】
次に第３の実施例として上述の第２の実施例の変形例を示す。これは、ＣＣＤ３２へのマスキングのかわりに、ミラーにマスキングを行なったものである。
図２０は、カメラ装置１Ｂにおける、前実施例の図１４に対応するＣＣＤカメラ本体５０とミラー６０のレイアウトを示し、同様に三角法で表わしている。
動画像を撮影できるＣＣＤカメラ本体５０は、前記各実施例のものと同じく左右一括反転機能を有している。
ＣＣＤカメラ本体５０のレンズ筐体５１の光学系の左右方向の画角は約５０°である。画角はレンズの焦点距離ｆとＣＣＤ素子５２のサイズにより決まり、例えば１／３インチのＣＣＤ素子（４．８×３．６ｍｍ）を使用する場合には、ｆ＝５．１ｍｍとすればよい。
【００７１】
２枚の反射面を備えるミラー６０がレンズ筐体５１の前方に配置される。ミラー６０はレンズ筐体５１の光軸を含み画面の左右方向に相当する辺と平行な平面Ｍで分離され、左側を向いた反射面６１は平面Ｍよりも上方にのみ、右側を向いた反射面６２は平面Ｍよりも下方にのみ存在する。
前実施例と同様に、ＣＣＤカメラ本体５０の左右方向と水平面とが一致した状態から、ＣＣＤカメラ本体５０とミラー６０を同時にレンズ筐体５１の光軸を中心にθ＝９．６°回転させてある。このθの値は上下方向の画角３８．６°の１／４である。
【００７２】
ミラー６０はその２枚の反射面で、ＣＣＤカメラ本体５０の撮影画角を全てカバーするようにそのサイズが決定される。
反射面の角度は、ＣＣＤカメラ本体の画角や撮影する範囲により決定されるが、ここではレンズ筐体５１の光軸と反射面の法線のなす角度を左右ともに５２．５°としてある。
【００７３】
ミラー６０の各反射面上の端部には、マスキングが施されている。マスク６７は例えば拡散反射率が低い艶消しの黒色塗装として、反射虚像ができないようにしてある。マスク６７にはこのほか光を拡散するもの、あるいは光を吸収するもの等が用いられる。
このマスク６７の部分と反射面の残余の部分とで、ＣＣＤカメラ本体５０の撮影画角を全て覆うが、反射虚像を撮影する視野内にはマスク６７面が入り込まないようにしてある。
車両への取り付け姿勢を含め、その他の構成は前実施例と同じである。なお、本実施例では前実施例とは上下の反射面の向きを逆にしてある。
【００７４】
本実施例によっても、ＣＣＤカメラ本体５０とミラー６０は同じ角度だけ回転させているため、撮影画面上でミラーの反射面の分離境界は水平となり、左右方向の撮影画面は上下に分割される。また、ＣＣＤカメラ本体５０とミラー６０を上下方向の画角の１／４だけ回転させているため、上下各半分のそれぞれの画面内で水平を中心に上下均分に撮影される。
【００７５】
なお、レンズ筐体５１の光軸とミラーの反射面法線のなす角度を５２．５°とすることにより、ミラー６０を介してＣＣＤカメラ本体５０の撮影する範囲は、図２１に示すように、車両Ｓの真横より後側１０°から前方約３５°の領域ＲＳＡとなる。ただし、マスク６７による分だけ画角が減少する。
そして、ミラー６０上に施したマスク６７のため、モニタに出力される画面には上半分（左側方の撮影画面）内には右端に、下半分（右側方の撮影画面）内には左端に指標ブロックが提示される。これにより、上半分が左側、下半分が右側であることの認識性が高められるという利点を有する。
【００７６】
なお、本実施例において、マスク６７の部分については平面である必要はなく、曲面になっていたり、あるいは、図２２のように、マスク６８が反射面６１、６２部分とは異なる角度を持っていてもよい。さらには、別の面となっていてもよく、ケースの一部を兼用することも可能である。
【００７７】
図２３は第４の実施例を示す。これは２台のＣＣＤカメラ本体を備えて個別に車両の左右方向を撮影するものである。
このカメラ装置１Ｃは車両のバンパの上や、ナンバープレートの後側等に設置される。
カメラ装置１Ｃは、左右の側壁２Ｃａに樹脂やガラスからなる透明な窓３Ｃ、３Ｃを備えるケース２Ｃ内に２台のＣＣＤカメラ本体７０Ｒ、７０Ｌを有して構成される。各ＣＣＤカメラ本体７０Ｒ、７０Ｌはそれぞれ略水平方向を向き、車両の右側、左側の真横から若干量前方に傾けて設置されて、上記の窓３Ｃ、３Ｃを通してケース２Ｃ外部を撮影する。
【００７８】
２台のＣＣＤカメラ本体７０Ｒ、７０Ｌはそれぞれ動画像を撮影できる同一仕様に構成され、上記各実施例のものと同様にレンズ筐体７１、ＣＣＤ素子７２、回路基板７３を備えている。
各ＣＣＤカメラ本体７０Ｒ、７０Ｌの撮影画面のアスペクト比は８：３から１０：３に設定されている。これは、ＣＣＤ素子７２の受光面のサイズによって、またはマスキングあるいは後段の信号処理によって実現される。
レンズ筐体７１の光学系の左右方向の実質的な画角は約４０°となっている。
【００７９】
ケース２Ｃ内には信号合成回路７５が設けられ、２台のＣＣＤカメラ本体７０Ｒ、７０Ｌによる撮影画面が内部の信号処理回路でそれぞれ左右一括反転された信号が合成されて、一つの画面の映像信号として出力される。例えば、各８：３のアスペクト比の画面を上下につなげてアスペクト比４：３のコンポジットビデオ信号（ＮＴＳＣ信号）出力が出力される。
【００８０】
上記信号合成回路７５における合成に際しては、上下の画面を互いに左右方向にオフセットさせることにより、モニタには第２の実施例の図１６と同様の表示画面が得られる。
すなわち、右側方の撮影画面である表示画面の上半分内には左端に、左側方の撮影画面である下半分内にはその右端に黒色表示された指標ブロックができる。これにより、上半分が右側、下半分が左側であることの認識性を高めている。また、上半分と下半分の表示を入れ替えることも容易である。
【００８１】
この実施例によっても、見通しの悪い交差点での安全確認が可能で、さらに、各方向について横長の画面が得られるので、左右方向（水平方向）の画角を広くとることが可能である。
【００８２】
【発明の効果】
以上のとおり、本発明は、車両の横方向から前方方向にかけての範囲の映像をモニタに表示させるための出力画面映像信号を出力する車両用カメラにおいて、左右外側に向いた２つの反射面を車両前方側の端で連結したミラーと、この２つの反射面を撮影範囲として撮影方向を車両の前進方向に関して後方に向けた撮影手段とを備え、撮影手段がその撮影画像を一括左右反転して映像信号を出力するものとしたので、左右独立の画像反転処理を行なう特別のコントローラなど不要として安価に作製でき、しかも小型に構成されるという効果を有する。
【００８３】
そして、２つの反射面を、車両を幅方向に２分する中心面に平行な面に対して略対称に配置することにより、右側左側とも、撮影する範囲が最大限に広く確保される。
また、撮影手段の光学系の光軸を略水平とし、反射面の上下略中央を通るように配置することにより、水平方向を中心に上下が均等に撮影され、確認する領域が容易確実に撮影視野に入るという効果が得られる。
さらにまた、撮影手段とミラーをケースに格納し、撮影手段が窓を介してケース外部を撮影するように構成することにより、車体外部の悪環境に設置しても保守管理が容易となる。
【図面の簡単な説明】
【図１】本発明の第１の実施例を示す外観斜視図である。
【図２】第１の実施例の水平断面図である。
【図３】実施例の取付状態を示す図である。
【図４】モニタの設置例を示す図である。
【図５】カメラ装置とモニタの接続を示す図である。
【図６】カメラ装置の要素の位置関係を求める線図である。
【図７】カメラ装置の要素の位置関係を求める線図である。
【図８】カメラ装置の寸法諸元例を示す図である。
【図９】実施例の作用を示す説明図である。
【図１０】実施例による撮影視野を示す説明図である。
【図１１】カメラ装置の他の取付例を示す図である。
【図１２】第２の実施例を示す図である。
【図１３】マスクを示す図である。
【図１４】ＣＣＤカメラ本体とミラーの位置関係を示す説明図である。
【図１５】第２の実施例の作用を示す説明図である。
【図１６】第２の実施例におけるモニタ表示例を示す図である。
【図１７】ＣＣＤカメラ本体とミラーの位置関係の比較例を示す図である。
【図１８】比較例における撮影画像を示す図である。
【図１９】比較例における作用を示す説明図である。
【図２０】第３の実施例を示す図である。
【図２１】第３の実施例による撮影視野を示す説明図である。
【図２２】マスク部の他の例を示す図である。
【図２３】第４の実施例を示す図である。
【図２４】第１の従来例を示す図である。
【図２５】第１の従来例における撮影画像を示す図である。
【図２６】画像反転のためのコントローラの例を示すブロック図である。
【図２７】コントローラにおける処理を示す説明図である。
【図２８】画像反転のための他のコントローラの例を示すブロック図である。
【図２９】コントローラにおける処理を示す説明図である。
【図３０】第２の従来例を示す図である。
【図３１】左右独立反転の境界がずれた場合の撮影画像を示す示す図である。
【符号の説明】
１、１Ａ、１Ｂ、１Ｃ カメラ装置
２、２Ａ、２Ｃ ケース
３、３Ａ、３Ｃ 窓
４、４Ａ 透明体
６ 切り替えスイッチ
８ モニタ
１０、３０、５０、７０Ｒ、７０Ｌ ＣＣＤカメラ本体
１１、３１、５１、７１ レンズ筐体
１２ ＣＣＤ素子（２次元イメージセンサ）
１３ 回路基板
１４ 信号処理回路（信号処理手段）
１５ 電源回路
２０ Ｖ字型ミラー
２１、２２ 反射面
３２、７２ ＣＣＤ素子（２次元イメージセンサ）
３２ａ 受光面
３３、７３ 回路基板
４０、６０ ミラー
４１、４２、６１、６２ 反射面
４７、６７、６８ マスク
４８UP、４８LW 窓
７５ 信号合成回路
８０ ＣＣＤカメラ本体
８３、８４ ミラー
１０１、２０１ カメラ装置
１０２ ケース
１０３、２０３ ＣＣＤカメラ本体
１０４、２０４ Ｖ字型ミラー
１１０、１１０Ａ コントローラ
１１１ ラインメモリ
１１２ モニタ
１１３ Ｔ−フリップフロップ
１１４ アップダウンカウンタ
１１５ ランダムロジック回路
１１６ ラッチ回路
ＢＫ 指標ブロック
ＧＡHR、ＧＡHL 撮影画面
ＧHR、ＧHL 反転画像
ＧＲ、ＧＬ、ＧＡＲ、ＧＡＬ 正転画像
Ｋ ダッシュボード
Ｐ 光軸
Ｑ 死角となる領域
ＲＳ 撮影視野
Ｓ 車両
Ｘ カメラ視線[0001]
[Industrial application fields]
The present invention relates to a vehicular camera for confirming left and right road conditions in an intersection with poor visibility.
[0002]
[Prior art]
In some cases, such as when the vehicle is traveling from an alley with poor visibility to the left and right on the main road, the left and right safety confirmations cannot be made unless the vehicle is advanced to the position where the front end of the vehicle protrudes to the front road. In such a case, there has been proposed a vehicle camera that displays the left and right road conditions as images before proceeding to a position where the driver can directly view.
[0003]
As a first example of such a conventional vehicle camera, for example, FIG. 24 shows one disclosed in Japanese Patent Laid-Open No. 6-171426. (A) of the figure is an external perspective view, and (b) shows an installed state.
The camera device 101 configured as a unit integrally with the case 102 includes a CCD camera body 103 inside, and further, an optical lens system, a CCD element, its signal processing circuit, a power supply circuit, and the like are provided inside the CCD camera body. Built in. On the front surface of the CCD camera main body 103, a V-shaped mirror 104 having a reflecting surface facing outward is disposed.
[0004]
The camera apparatus 101 is attached to the front end of the vehicle with the CCD camera body 103 positioned behind the V-shaped mirror 104, and as shown in FIG. It is installed so as to reflect and guide the range to the front to the CCD camera body 103.
In this way, the CCD camera body 103 captures a reflected virtual image by the V-shaped mirror 104, so that a captured image in both the left and right directions is obtained by a single camera device. This photographed image is displayed on a monitor installed at an appropriate part around the driver's seat.
[0005]
Here, as shown in FIG. 25A, the image captured by the CCD camera body 103 is an inverted image in the right direction on the right half of the image and an inverted image in the left direction on the left half of the image. Therefore, in order for the captured image to be displayed on the monitor as shown in (b), the image is corrected so that the right half of the image becomes a normal rotation image in the right direction and the left half of the image becomes a normal rotation image in the left direction. There is a need to.
[0006]
As one of the methods for correcting these inverted images, a controller 110 as shown in FIG. 26 is used. Here, left and right independent inversion is performed, and an inverted image of only the right half of the image and an inverted image of only the left half of the image are output.
First, the video signal from the camera device 101 is once written in the line memory (memory for one line in the horizontal direction) 111 and then read out and output to the monitor 112.
[0007]
A T-flip-flop 113 that receives a horizontal synchronizing signal a of a video signal from the CCD camera body is provided, and an up / down counter 114 that receives an output b from this and a random logic circuit 115 are connected. The random logic circuit 115 sets an initial value c for the up / down counter 114. The up / down counter 114 is controlled to be set and reset by the T-flip flop 113, and sets the read address d to the line memory 111 and sets the write address e via the latch circuit 116. ing.
[0008]
The controller 110 executes processing as follows.
Here, the number of pixels for one line is N, and description will be made with reference to FIG.
First, in step S1, an image signal for one line is written sequentially from the first line memory as w1.
In step S2, at the same time as the last N-th write starts, reading starts as r1 in the opposite direction (toward the first) from the center of the line memory (N / 2nd) as the starting point. To do.
Almost simultaneously with the start of step S2, as step S3, writing of the image signal of the next line is started as in w2. Here, the image signal of the next line is sequentially written at the point where the reading is completed in step S2.
[0009]
After reading out the first image signal, in the next step S4, starting from the end (Nth) of the line memory as the starting point, in the direction opposite to the previous writing of w1 (toward the N / 2 + 1th), r2 Start reading.
Almost simultaneously with the start of step S4, the writing of the image signal of the next line is started as w3 as step S5. Here, the read point is held in the latch circuit, and the image signal of the next line is sequentially written to the point where the read is completed in step S4.
[0010]
Simultaneously with the start of writing to the last N / 2 + 1th, in step S6, starting from the first (first) of the line memory, reading is performed as r3 in the direction opposite to the writing of w3 (toward the Nth). To start.
Almost simultaneously with the start of step S6, the writing of the image signal of the next line is started as w4 as step S7. Here, the next line image signal is sequentially written at the point where the reading is completed in step S6.
The writing of w4 corresponds to the writing of w1 in step S1, and the above steps are repeated thereafter.
[0011]
Completion of reading and writing of signals for one line is determined by a horizontal synchronizing signal. The random logic circuit 115 switches the read and write start points in each step.
Thus, the left and right surfaces can be reversed by reading in the opposite direction after being divided into two in the horizontal direction.
[0012]
Incidentally, some commercially available CCD camera bodies have a simple collective left-right reversing function with the entire screen as one unit. This function is included in the signal processing circuit, and the functional part has a configuration as shown in FIG. 28, and the random logic circuit 115 is omitted from the controller of FIG. Yes.
Processing in this case will be described with reference to FIG.
The number of pixels for one line is N, and the number of line memory areas is N + 1.
First, in step S11, an image signal for one line is written as w1 in order from the first line memory.
[0013]
In step S12, at the same time as the end of writing to the last Nth, reading starts from the written point (Nth) in the opposite direction (toward the first) as r1.
Simultaneously with the start of step S12, writing of the image signal of the next line is started as step S13. Here, the image signal of the next line is sequentially written to the point immediately before the point read in step S12. That is, if the point read in step S12 is the Mth, the image signal of the next line is sequentially written to the M + 1th point as w2.
[0014]
In step S14, at the same time as the last writing to the second end, reading is started as indicated by r2 in the opposite direction (toward the Nth) from the writing point (second) as the starting point.
Almost simultaneously with the start of step S14, writing of the image signal of the next line is started as step S15. Here, writing is performed at the point immediately before the point where the reading is completed in step S14. That is, if the point read in step S14 is the Mth, the image signal of the next line is written sequentially to the M−1th point as w3.
[0015]
This writing of w3 corresponds to the writing of w1 in step S11, and the above steps are repeated thereafter.
Completion of reading and writing of signals for one line is determined by a horizontal synchronization signal.
In this way, the image is inverted by reading the written signal in the opposite direction to the writing.
[0016]
Next, as a second conventional example, Japanese Patent Application Laid-Open No. 6-171425 discloses a camera device that eliminates the need for image reversal.
As shown in FIG. 30, the camera device 201 is a combination of a CCD camera main body 203 and a V-shaped mirror 204 with the reflection surface on the inside. The CCD camera body 203 has the same configuration as the CCD camera body 103 of the previous embodiment.
The CCD camera body 203 is installed at a predetermined angle in the lateral direction (left direction) at the front end portion of the vehicle in order to capture a field of view from the front side.
[0017]
The V-shaped mirror 204 is arranged such that the reflection surfaces 205 and 206 are opposite to the direction of the CCD camera main body 203 (right direction) and the reflection surfaces are arranged in the front-rear direction.
In the figure, as indicated by the line-of-sight directions s1 and s2, the CCD camera body 203 directly captures one direction that it faces, and the other direction is a reflected image reflected twice by the reflecting surfaces 205 and 206 of the V-shaped mirror. Shoot.
According to this, a normal rotation image in both the left and right directions can be obtained with a single camera without using a controller.
[0018]
[Problems to be solved by the invention]
However, in the first conventional vehicle camera described above, the controller 110 that performs the left / right independent reversal has a function for reading from the middle in addition to the circuit configuration of the signal processing circuit of the camera having the collective left / right reversal function. There is a problem that a random logic circuit 115 for setting an address is necessary, and a special controller having a large number of parts must be provided separately, resulting in an increase in system cost.
[0019]
Further, when the left and right halves are reversed using such a controller, there is a problem that the center of the V-shaped mirror 104 (V corner) and the boundary of the left and right independent inversions do not match. That is, in the output image of the CCD camera body 103, the center of the left and right independent inversion does not change because it is electrically processed, but a predetermined tolerance must be allowed for the attachment of the V-shaped mirror 104, and Since it is attached to a vehicle and used, it vibrates while the vehicle is running and is expected to change over time. Thus, when the center of the V-shaped mirror and the boundary of the left and right independent inversion in the controller are shifted, for example, as shown in FIG. 31A, the image on the monitor 102 is reflected by the right mirror at the edge of the left screen. A part of the virtual image enters and the display quality is deteriorated.
As a countermeasure, it is conceivable to widen the boundary between the left and right independent inversions, but this causes a problem that the photographing range in the left and right direction becomes narrow as shown in FIG.
[0020]
On the other hand, the captured image of the CCD camera body is a right side inversion image on the right half and a left side inversion image on the left half. Since the image on the left side is displayed on the right half and the image on the right side is displayed on the left half on the screen, the batch inversion function was not utilized.
[0021]
In addition, the second conventional vehicle camera has a problem in that the size of the entire apparatus is increased because the V-shaped mirror 204 is disposed so as to protrude in the front-rear direction of the vehicle.
Therefore, the present invention pays attention to such a conventional problem, and eliminates the need for independent image reversal processing by a special controller or the like, and further provides a vehicle camera configured to be small while ensuring a wide left and right angle of view. The purpose is to provide.
[0022]
[Means for Solving the Problems]
For this reason, the present invention according to claim 1 is mounted on a vehicle. , The image of the range from the lateral direction of the vehicle to the forward direction A camera that outputs an output screen image signal to be displayed on a monitor, and each of two reflecting surfaces is a vehicle Forward While facing the left and right outside of the direction, Front end of vehicle , A two-dimensional image sensor, an optical system, and signal processing means. Forward The two reflecting surfaces are set as shooting ranges in the rear direction with respect to the direction, and the shooting means outputs a video signal obtained by inverting the shot image left and right at once.
The mirror preferably has two reflecting surfaces arranged substantially symmetrically with respect to a plane parallel to a central plane that bisects the vehicle in the width direction, and is substantially perpendicular to the horizontal plane.
Further, the photographing means is preferably arranged so that the optical axis of the optical system is substantially horizontal and passes through the upper and lower centers of the two reflecting surfaces of the mirror.
[0023]
Further, the photographing means and the mirror are stored in the case, and the case is provided with transparent windows on the left and right side walls corresponding to the two reflecting surfaces of the mirror, and the photographing means is disposed outside the case through the reflecting surface and the window. It is desirable to configure to shoot.
The photographing means and the mirror can be arranged on a substantially central plane that divides the width of the vehicle in the vicinity of the front end of the vehicle or in front of the driver's seat in the vicinity of the front end of the vehicle.
[0024]
According to the seventh aspect of the present invention, in particular, the two reflecting surfaces are flat, substantially perpendicular to the horizontal plane, and substantially symmetrical with respect to a plane parallel to the center plane that bisects the vehicle in the width direction. The outer diameter of the optical system is defined as a preferable distance between the reflecting surface and the optical system when the optical axis of the optical system is arranged substantially horizontally and passes through the upper and lower centers of the two reflecting surfaces. Where R is the radius, 2 · θm is the angle between the normals of the reflecting surfaces, and d is the distance between the reflecting surface and the optical system.
R · tan (90 ° -2 · θm) ≦ d
≦ R ・ tan (90 ° −2 ・ θm) +2 (mm)
Was established.
[0025]
The invention according to claim 8 also defines a preferable length in the horizontal direction of the reflecting surface. The angle of view of the photographing means is θ0, the radius of the entrance pupil of the optical system is r, and the method of each surface of the reflecting surface is used. The angle formed by the line is 2 · θm, the distance between the reflecting surface and the optical system is d, and the horizontal length of one reflecting surface is L.
[Expression 2]

Was established.
[0026]
The invention according to claim 9 also defines a preferable angle between the reflecting surfaces, and the angle of view of the photographing means is θ0, and the angle formed by the normal lines of the reflecting surfaces is 2 · θm.
45 ° -θ0 / 4 ≦ θm ≦ 50 ° -θ0 / 4
Was established.
[0027]
[Action]
In claim 1, Front end of vehicle The photographing means shoots from the V-shaped apex side with the two reflecting surfaces of the V-shaped mirrors connected in step S as the photographing range. Shooting means is vehicle Forward Since the image is taken facing backwards from the direction, the image taken has the left direction viewed from the vehicle on the right side and the right direction on the left side, and the reflected virtual image by the mirror is horizontally reversed. When the captured image is reversed horizontally by the signal processing means, the left direction as viewed from the vehicle is changed to the left side of the output screen, the right direction is changed to the right side of the output screen, and each becomes a normal rotation image.
[0028]
If the two reflecting surfaces are arranged substantially symmetrically with respect to a plane parallel to the center plane that bisects the vehicle in the width direction, the shooting range is secured to the maximum on both the right and left sides.
If the optical axis of the optical system is substantially horizontal and is arranged so as to pass through the upper and lower centers of the reflecting surface, the upper and lower parts are photographed evenly around the horizontal direction, and the area for safety confirmation easily and surely enters the photographing field of view.
If the photographing means and the mirror are stored in the case, and the photographing means is configured to photograph the outside of the case through the window, maintenance management is easy even when installed in a bad environment outside the vehicle body.
[0029]
According to the seventh, eighth and ninth aspects of the present invention, the distance between the reflecting surface and the optical system, the length of the reflecting surface in the horizontal direction, and the angle of the reflecting surface are defined so that the reflecting surface can be used without waste. The whole is compactly configured.
[0030]
【Example】
The present invention will be described below with reference to the drawings.
1 is an external perspective view of a camera apparatus showing a first embodiment of the invention, FIG. 2 is a horizontal sectional view thereof, and FIG. 3 is a perspective view showing a state where the camera apparatus is attached to a front end portion of a vehicle.
A CCD camera body 10 is provided in a box-shaped case 2 with the optical system formed in the lens housing 11 facing rearward (vehicle side). The CCD camera body 10 includes a CCD element 12 as a two-dimensional image sensor in addition to an optical system. A signal processing circuit 14 and a power supply circuit 15 are built in a circuit board 13, and a composite video signal as a video signal is obtained by capturing a moving image. Is output. The signal processing circuit 14 has a function of inverting the entire screen at the same time horizontally by the same configuration as shown in FIG. 28, which is often used in general commercial cameras.
[0031]
A V-shaped mirror 20 is disposed behind the CCD camera body 10 so as to face the optical system with the planar reflecting surfaces 21 and 22 facing outward.
The case 2 has a waterproof structure, and a window 3 including a transparent body 4 is provided at a portion corresponding to the reflecting surfaces 21 and 22 of the side wall 2a. As the transparent body 4, a highly transparent transparent resin such as acrylic or polycarbonate, glass or the like is used. The CCD camera body 10 photographs the outside of the case 2 through the window 3, and in FIG. 2, the range sandwiched between the line-of-sight directions u1 and u2 and the range sandwiched between v1 and v2 are the shooting range.
[0032]
As shown in FIG. 3, the camera device 1 unitized in the case 2 is mounted on the center plane of the vehicle S (the plane that bisects the vehicle in the width direction) in the vicinity of the forefront.
At this time, the posture is set so that the optical axis of the optical system of the CCD camera body 10 is parallel to the horizontal plane and the normal lines of the reflecting surfaces 21 and 22 are parallel to the horizontal plane so that the horizontal line is a horizontal line on the monitor screen. Decided and installed. In other words, the CCD camera body 10 and the reflecting surface are symmetrical with respect to the horizontal plane, so that the upper and lower parts are photographed uniformly around the horizontal direction.
[0033]
In addition, the video imaged by the camera device 1 is displayed on a monitor 8 that is installed on the dashboard K as shown in FIG.
As shown in FIG. 5, a changeover switch 6 is provided between the camera device 1 and the monitor 8 so that the image output to the monitor 8 can be turned ON / OFF by manual switching by the driver.
[0034]
Here, specific numerical values for the specifications of the camera device 1 will be obtained.
The shooting range varies depending on the offset amounts in the left and right directions of the CCD camera body 10 and the reflecting surfaces 21 and 22 and the inclination angles of the CCD camera body and the reflecting surface. In this embodiment, the shooting range is symmetrical and the screen ratio is Is 1: 1.
With reference to FIG. 6 and FIG. 7 which is a diagram of this, the horizontal field of view of the CCD camera body 10 is θ0, the angle between the normal lines of the reflecting surfaces 21 and 22 is 2 · θm, CCD The distance between the lens of the camera body (the front end of the lens housing 11) and the reflecting surfaces 21 and 22 is d, and the horizontal length of one reflecting surface is L, and these conditions to be satisfied are obtained. In FIG. 7, (b), (c), and (d) show partial details of (a).
[0035]
First, when the angle between the vehicle width direction and the rear end direction of the shooting range is θr, θr is considered in consideration of the reflection of the vehicle body and the effectiveness of the image.
0 ° ≦ θr ≦ 10 °
It is desirable that
At this time, the angle 2 · θm formed by the normal lines of the respective surfaces of the reflecting surfaces 21 and 22 is the triangle ECD in FIG.
90 ° + θ0 / 2 + {θm + (θm−θr)} = 180 °
That is,
θm = 45 ° −θ0 / 4 + θr / 2
Because of the relationship
45 ° −θ0 / 4 ≦ θm ≦ 50 ° −θ0 / 4
Must be satisfied.
[0036]
When the radius of the outer shape of the lens housing 11 is R, in order for the lens housing 11 not to be reflected in the reflected virtual image, the distance d between the lens and the reflecting surface is as shown in FIG.
d ≧ R · tan (90 ° -2 · θm)
Must be satisfied.
When d increases, the reflecting surfaces 21 and 22 also need to be increased, leading to an increase in the size of the camera device 1. Moreover, about 2 mm is required as a mounting tolerance. From these,
R · tan (90 ° -2 · θm)
≦ d ≦ R · tan (90 ° -2 · θm) +2
The condition is obtained.
[0037]
Subsequently, when the angle of view of the CCD camera body 10 is θ0 and the radius of the entrance pupil of the optical system is r, the entire field of view of the CCD camera body captures the reflecting surfaces 21 and 22, and the V-shaped mirror 20 Is as small as possible in the square ACDB in FIG.
h ′ = L · sin θm
h ″ = L · cos θm−r
h ″ / (h ′ + d) = tan (θ0 / 2)
From the relationship
[Equation 3]

And it is sufficient.
[0038]
Here, the dimensions of the CCD camera main body 10 are set to be a lateral direction of the apparatus assuming that the horizontal angle of view is θ0 = 60 °, the radius R of the lens housing 11 is 7.0 mm, and the optical system entrance pupil r is 2.0 mm. A range from the front to the front (that is, θr = 0 °) is taken.
At this time,
θm = 30 °
4.04 ≦ d ≦ 6.04 (mm)
It becomes.
[0039]
From this, if d = 5 mm,
[Expression 4]

It becomes.
Further, assuming that the size of the circuit board 13 of the CCD camera body is vertical × horizontal × thickness is 30 × 30 × 5 (mm) and the length of the lens housing 11 is 20 mm, the necessary unit dimensions are as follows:
Length: 5 + 20 + 5 + 10.5 × sin (30 °) = 35.25 (mm)
In addition, the width is the reflective surface,
2 · L · sin (30 °) = 10.5 (mm)
And depends on the size of the circuit board 13. Here, the width is 30 mm.
[0040]
The heights of the reflecting surfaces 21 and 22 are set such that the ratio of the width to the height of the field of view of the CCD camera body is 4: 3.
10.5 × 3/4 = 7.9 (mm)
This also depends on the size of the circuit board. Here, the height is 30 mm.
[0041]
Summarizing the above, the dimensions are as shown in FIG. 8, and considering the case 2, the minimum required unit size is
Length x width x height = 40 x 30 x 30 (mm)
It will be about.
The circuit board 13 of the CCD camera main body actually requires about one more for the signal processing circuit 14 and the power supply circuit 15, but can be sufficiently accommodated in a space such as the lower part of the lens housing 11.
[0042]
Next, the operation will be described.
As shown in FIG. 9A, the CCD camera body 10 captures a reflected virtual image passing through the windows (not shown) and passing through the reflecting surfaces 21 and 22. Then, as shown in (b), in the video imaged by the CCD camera body 10, the right half of the image becomes a reverse image GHL on the left side of the front of the vehicle, and the left half of the image becomes a reverse image GHL on the right side of the front of the vehicle.
This image is horizontally reversed at once by the signal processing circuit 14 built in the CCD camera body 10.
If the left and right are reversed, the screen in each direction can be corrected. As a result, as shown in (c), normal images GR and GL that present the right and left fields of view on the right and left half surfaces, respectively, are obtained. This video output is sent to the monitor 8 and displayed as it is.
[0043]
As described above, according to this embodiment, the CCD camera body 10 is directed rearward, and the V-shaped mirror 20 facing the lens and the reflection surface facing outward is arranged to photograph the left and right sides of the vehicle, Since the video signal obtained by reversing the entire screen at the same time by the signal processing circuit 14 of the CCD camera body is sent to the monitor 8 and displayed on the monitor 8, the normal rotation image is displayed on the monitor 8 without requiring a complicated and expensive additional controller. Can be displayed.
[0044]
As a result, when a vehicle with a hood such as a sedan is running on a main road from an alley with bad visibility on both sides, such as a fence or a building, the tip of the vehicle S protrudes on the main road as shown in FIG. The left and right directions are photographed at the same position, and the field of view RS covers an area Q that is a blind spot from the driver's own eyes, and the monitor display indicates traffic conditions such as main roads (cars, bicycles, pedestrians Etc.) can be confirmed.
[0045]
By making the shooting range symmetrical, it is easy to determine where the driver actually sees when viewing the monitor image.
Similarly, since the optical axis system of the CCD camera body 10 is installed in a direction in which the upper and lower parts are uniformly imaged with respect to the horizontal direction, an area for safety confirmation easily and surely enters the imaging field of view. Further, since the left / right division ratio of the screen is set to 1: 1, the shooting range is ensured as wide as possible on both the right and left sides for easy confirmation.
[0046]
Further, since the camera device 1 is mounted on the center plane at the forefront of the vehicle S, the camera device 1 is least affected by the approach angle to the intersection of the vehicle, and the most distal end of the vehicle even if the approach angle changes. There is an advantage that a nearby position can be secured.
[0047]
In the above embodiment, the positional relationship between the reflecting surfaces 21 and 22 with respect to the CCD camera body 10 is symmetrical with respect to the top, bottom, left and right, but the present invention is not limited to this. That is, the positional relationship between the CCD camera body and the V-shaped mirror has a degree of freedom in the amount of offset between each other and in each inclination angle, and the photographing range and the like can be changed by these.
When the offset amount between the CCD camera body 10 and the reflecting surfaces 21 and 22 changes, the ratio of the reflected virtual image formed on each reflecting surface of the V-shaped mirror to the photographing screen changes. When the tilt angle of at least one of the CCD camera body or the two reflecting surfaces changes, the angle range reflected on the reflecting surface changes. Accordingly, not only the horizontal shooting range but also the vertical shooting range can be arbitrarily changed as necessary.
[0048]
In the embodiment, the camera device 1 is mounted on the center plane of the vehicle S, but the normal driver's seat is offset laterally from the center of the vehicle. It can also be installed in front of the right driver. According to this, the distance to the subject (another vehicle or the like) is close to that actually seen by the driver himself, and it becomes easier to grasp the perspective of the subject.
[0049]
In addition, as the installation site of the camera device 1 on the vehicle body, any point in front of the driver's seat such as the hood SB or the lower part of the bumper BP can be selected.
In addition, in the embodiment, the camera device 1 and the monitor 8 are connected by the manual switching switch 6. However, an automatic switching switch that operates according to the vehicle speed or the like can be provided.
[0050]
In addition, an imaging tube or the like can be used as the photographing means of the camera device 1 instead of the CCD camera body 10. A flat reflector is used as the reflecting surface of the V-shaped mirror, but a reflecting surface in which curved surfaces are connected may be used instead. For example, if it is a convex mirror, the angle of view will spread.
The monitor 8 is not limited to a dedicated monitor, and a monitor for a television receiver, a monitor for navigation, and the like can be used only when necessary.
[0051]
FIG. 12 shows a second embodiment of the present invention. In this embodiment, the left and right shooting screens are divided into upper and lower parts and displayed on one monitor.
In the figure, (a) is a top view showing the inside after removing the upper wall of the case 2A, (b) is a rear view showing the inside by removing the end wall 2Ab on the CCD camera body 30 side, and (c) is the side wall 2Aa removed. FIG.
In the camera apparatus 1A, an optical system in which a CCD camera body 30 having a CCD element 32 as a two-dimensional image sensor is formed in a lens housing 31 is provided in a box-shaped case 2A facing forward (vehicle traveling direction). It has been.
[0052]
The CCD camera body 30 has a circuit board 33 including a signal processing circuit in addition to the lens casing 31 and the CCD element 32. When a DC 12V is applied as a power source for a passenger car, a moving image is taken and a composite video signal as a video signal is output. The signal processing circuit has a function of inverting the entire screen, which is often used in general commercial cameras, in a horizontal direction.
[0053]
In front of the CCD camera main body 30, a mirror 40 having flat reflecting surfaces 41 and 42 facing the lens housing 31 is arranged symmetrically about the optical axis P.
The case 2A has a waterproof structure, and a window 3A including a transparent body 4A is provided at a portion of the side wall 2Aa corresponding to the reflecting surface of the mirror 40. The CCD camera body 30 photographs the outside of the case 2A through this window 3A. As the transparent body 4A, as in the transparent body 4 of the previous embodiment, a highly transparent transparent resin such as acrylic or polycarbonate, glass, or the like is used.
In the figure, for the mirror 40, the white surface represents a reflective surface and the hatched surface represents a non-reflective surface. The same applies to the other drawings.
[0054]
The camera device 1A unitized in the case 2A is installed on the bumper BP at the center of the vehicle width (in front of the grill) or on the rear side of the license plate, etc., as in the first embodiment. The optical axis of the CCD camera main body 30 coincides with the front-rear direction of the vehicle, and is mounted forward and horizontally as described above.
[0055]
The optical system has an angle of view of about 45 ° in the left-right direction (= horizontal direction). The angle of view is determined by the focal length f of the lens and the size of the CCD. For example, when a 1/3 inch (4.8 × 3.6 mm) CCD element is used, f = 5.8 mm may be set.
Further, as shown in FIG. 13, on the light receiving surface 32a of the CCD element 32, a mask 47 in which the upper and lower windows 48UP and 48LW are slightly offset in the horizontal direction is attached.
[0056]
As shown in FIG. 14, the positional relationship between the CCD camera body 30 and the mirror 40 with respect to the case 2A is that the layout as shown in (a) is rotated around the optical axis P of the CCD camera body 30. (B). In the figure, the lens housing 31, the CCD element 32, and the mirror 40 are extracted and shown in a trigonometric method.
First, in (a), the layout is such that the horizontal direction of the CCD camera body 30 and the horizontal plane coincide, and the optical axis of the lens housing 31 is horizontal.
[0057]
The two reflecting surfaces 41 and 42 of the mirror 40 are separated by a horizontal plane including the optical axis P of the lens housing 31, and the reflecting surface 41 facing the right side exists only above the horizontal line including the optical axis, The facing reflecting surface 42 exists only below the horizontal line including the optical axis.
The size of the mirror 40 is determined so that the two reflection surfaces 41 and 42 cover the entire shooting angle of view of the CCD camera body 30.
[0058]
The angle of the mirror needs to be changed depending on the angle of view of the CCD camera body 30 and the shooting range. Here, the angle formed by the optical axis of the lens housing 31 and the normal of the reflecting surface is 56.3 ° on both the left and right. did.
In the layout of (b), the CCD camera body 30 and the mirror 40 in (a) are simultaneously rotated about the optical axis of the lens housing 31 by θ = 8.6 °. The value of θ is ¼ of the vertical field angle of 34.5 °.
[0059]
Next, the operation will be described.
First, the CCD camera body 30 captures both the left and right directions outside the case 2A by capturing a virtual image reflected on the two reflecting surfaces of the mirror through the window.
Since the CCD camera body 30 and the mirror 40 are rotated and inclined by the same angle about the optical axis center, as shown in FIG. 15A, the boundary between the reflecting surfaces 41 and 42 of the mirror is horizontal on the photographing screen, and the right The left and right shooting screens GAHR and GAHL are divided vertically.
[0060]
In addition, since both the CCD camera body 30 and the mirror 40 are rotated by the same amount, in the upper half screen (the screen in which the right side is photographed in the illustrated example), the images are taken evenly in the vertical direction around the horizontal. Has been. Similarly, even in the lower half screen (the screen in which the left side is photographed in the illustrated example), the images are taken evenly with respect to the horizontal.
Here, since the image is divided into two parts in the upper and lower directions and the left and right directions are photographed, there is no need for independent reversal on the left and right. Normal rotation images GAR and GAL as shown in FIG.
FIG. 16 shows an example of the monitor display of the image taken by the CCD camera body 30 in this way.
[0061]
When the angle formed by the optical axis of the optical system of the lens housing 31 and the normal line of each reflecting surface of the mirror 40 is 56.3 °, the range captured by the CCD camera body 30 via the mirror 40 is as follows. Although it is 45 ° from the side of the vehicle, the angle of view is reduced to about 40 ° by the mask.
Because of the mask 47 affixed on the light receiving surface 32a of the CCD element 32, the screen output to the monitor is on the left side in the upper half right side shooting screen GAR and in the lower half left side shooting screen GAL. In the right end, an index block BK displayed in black is formed. This enhances the recognition that the upper half is the right side image and the lower half is the left side image.
[0062]
Here, in order to facilitate understanding of the operation of the present embodiment, a vertical division method in which the mirrors 83 and 84 are not rotated around the optical axis of the CCD camera body 80 will be described as a comparative example.
A comparative example is shown in FIG. The layout of (a) is almost the same as that of FIG. In this layout, when the output screen is viewed on a monitor, the right screen is displayed in the upper half and the left screen is displayed in the lower half. However, the screen on the right side that occupies the upper half shows only above the horizontal direction, and the screen on the left side that occupies the lower half shows only below the horizontal direction.
[0063]
This is because the mirrors 83 and 84 are installed perpendicular to the horizontal plane. Therefore, in order to project the portion below the horizontal direction on the upper half screen and also project the portion above the horizontal direction on the lower half screen, the upper mirror 83 is in the lower D direction and the lower mirror 84 is in the upper U direction. What is inclined in the direction is the layout of FIG.
Thereby, even the upper mirror 83 can see both the upper and lower directions around the horizontal plane.
[0064]
However, since the mirrors are tilted, there arises a problem that the other mirror is reflected on each mirror as shown in FIG. That is, since the respective mirrors separated by the horizontal plane including the optical axis are tilted and the opposite side of the horizontal plane including the optical axis is photographed, the respective mirrors 83 and 84 in the camera line of sight X as shown in FIG. The optical path of the line of sight XS is cut off by a part of the counterpart mirror at the part inside the point where the crosses, and the field of view narrows, and each other is reflected instead.
On the other hand, in this embodiment, the CCD camera body 30 is also rotated simultaneously with the tilt of the mirror 40. That is, the mirrors are rotated while their respective reflecting surfaces are not reflected on each other.
[0065]
The present embodiment is configured as described above, and a layout in which a mirror 40 in which two reflecting surfaces are separated by a horizontal plane is arranged in front of the CCD camera body 30, and both the CCD camera body 30 and the mirror 40 are rotated by the same amount. As a result, images are taken evenly on the top and bottom of the screen.
In this case, as in the first embodiment, a normal rotation image can be displayed on the monitor without requiring a complicated and expensive additional controller. Confirmation can be made.
[0066]
In addition, by providing a reflective surface of the same shape symmetrical about the optical axis, it is easy to determine where the driver actually sees the monitor image, and masking is performed on the light receiving surface of the CCD element. And the black-colored indicator block is presented at the contrasting parts of the upper and lower screens, so that the recognizability is high.
On the other hand, since both the CCD camera body and the mirror are rotated by the same amount, both mirrors are not reflected and a wide field of view is secured.
[0067]
Further, since the camera device 1A is mounted on the center plane at the forefront of the vehicle, it is hardly affected by the approach angle to the intersection of the vehicle, and even if the approach angle to the intersection changes, the vicinity of the tip of the vehicle There is an advantage that the position of can be secured.
Further, since the screens GAR and GAL in each direction are horizontally long, there is an effect that it is possible to take a wide angle of view in the left-right direction (horizontal direction) with the same magnification.
[0068]
In this embodiment, the possibility of misunderstanding about where the mirror 40 is symmetric with respect to the mirror 40 in the state before rotation around the optical axis is reduced. It is not limited to. Since the shooting range changes by changing the angle of the mirror, each can be set according to the required field of view and can be made different on the left and right.
[0069]
Similarly to the previous embodiment, if the reflecting surface of the mirror 40 is a convex surface, the angle of view can be widened.
Further, in this embodiment, the rotation angle θ around the optical axis is set to ¼ of the vertical angle of view of the CCD camera body 30 so that the shooting range is equal in the vertical direction around the horizontal direction. If desired, the rotation angle may be reduced when it is desired to make the upper side appear to be centered slightly above the horizontal, and the rotation angle may be increased when it is desired that the lower side be visible below the horizontal.
[0070]
Next, a modification of the second embodiment will be described as a third embodiment. In this case, masking is performed on the mirror instead of masking on the CCD 32.
FIG. 20 shows the layout of the CCD camera main body 50 and the mirror 60 corresponding to FIG. 14 of the previous embodiment in the camera apparatus 1B, and is similarly represented by trigonometry.
The CCD camera main body 50 capable of shooting a moving image has a left / right batch reversal function as in the above embodiments.
The field angle in the left-right direction of the optical system of the lens housing 51 of the CCD camera body 50 is about 50 °. The angle of view is determined by the focal length f of the lens and the size of the CCD element 52. For example, when a 1/3 inch CCD element (4.8 × 3.6 mm) is used, f = 5.1 mm may be used. .
[0071]
A mirror 60 having two reflecting surfaces is disposed in front of the lens housing 51. The mirror 60 is separated by a plane M including the optical axis of the lens housing 51 and parallel to the side corresponding to the left and right direction of the screen, and the reflection surface 61 facing the left side is a reflection facing the right side only above the plane M. The surface 62 exists only below the plane M.
As in the previous embodiment, the CCD camera body 50 and the mirror 60 are simultaneously rotated around the optical axis of the lens housing 51 by θ = 9.6 ° from the state where the horizontal direction of the CCD camera body 50 and the horizontal plane coincide. It is. The value of θ is ¼ of the vertical field angle of 38.6 °.
[0072]
The size of the mirror 60 is determined so that the two reflection surfaces cover the entire shooting angle of view of the CCD camera body 50.
The angle of the reflecting surface is determined by the angle of view of the CCD camera body and the shooting range. Here, the angle formed by the optical axis of the lens housing 51 and the normal line of the reflecting surface is 52.5 ° on both the left and right sides.
[0073]
Masking is applied to the end of each mirror 60 on the reflecting surface. The mask 67 is made of, for example, a matte black paint having a low diffuse reflectance so that a reflected virtual image cannot be formed. In addition, a mask 67 that diffuses light or absorbs light is used as the mask 67.
The portion of the mask 67 and the remaining portion of the reflection surface cover the entire shooting angle of view of the CCD camera body 50, but the mask 67 surface does not enter the field of view for capturing the reflected virtual image.
Other configurations including the mounting posture to the vehicle are the same as in the previous embodiment. In this embodiment, the direction of the upper and lower reflecting surfaces is reversed from that of the previous embodiment.
[0074]
Also in this embodiment, since the CCD camera main body 50 and the mirror 60 are rotated by the same angle, the separation boundary of the reflection surface of the mirror is horizontal on the photographing screen, and the photographing screen in the left-right direction is divided vertically. In addition, since the CCD camera body 50 and the mirror 60 are rotated by ¼ of the angle of view in the vertical direction, images are taken evenly in the vertical direction centering on the horizontal in the respective screens in the upper and lower halves.
[0075]
Note that, by setting the angle formed by the optical axis of the lens housing 51 and the normal surface of the reflecting surface of the mirror to 52.5 °, the range that the CCD camera body 50 captures through the mirror 60 is as shown in FIG. The region RSA is about 35 ° forward from 10 ° rearward of the vehicle S. However, the angle of view decreases by the amount corresponding to the mask 67.
Because of the mask 67 provided on the mirror 60, the screen output to the monitor is at the right end in the upper half (left-side shooting screen) and at the left end in the lower half (right-side shooting screen). An indicator block is presented. This has the advantage that the recognizability that the upper half is the left side and the lower half is the right side is enhanced.
[0076]
In the present embodiment, the portion of the mask 67 does not have to be a flat surface, but is a curved surface, or the mask 68 has an angle different from that of the reflective surfaces 61 and 62 as shown in FIG. May be. Furthermore, it may be another surface, and a part of the case can also be used.
[0077]
FIG. 23 shows a fourth embodiment. This is provided with two CCD camera bodies to individually photograph the left and right directions of the vehicle.
The camera device 1C is installed on the bumper of the vehicle, on the rear side of the license plate, or the like.
The camera device 1C includes two CCD camera bodies 70R and 70L in a case 2C having transparent windows 3C and 3C made of resin or glass on left and right side walls 2Ca. The CCD camera bodies 70R and 70L are each set in a substantially horizontal direction and are slightly inclined forward from the right side and the left side of the vehicle, and photograph the outside of the case 2C through the windows 3C and 3C.
[0078]
The two CCD camera bodies 70R and 70L are configured to have the same specification capable of capturing a moving image, and include a lens casing 71, a CCD element 72, and a circuit board 73 as in the above embodiments.
The aspect ratio of the shooting screen of each CCD camera body 70R, 70L is set from 8: 3 to 10: 3. This is realized by the size of the light receiving surface of the CCD element 72, or by masking or subsequent signal processing.
A substantial field angle in the left-right direction of the optical system of the lens housing 71 is about 40 °.
[0079]
A signal synthesis circuit 75 is provided in the case 2C, and the signals obtained by reversing the left and right batches of the shooting screens of the two CCD camera bodies 70R and 70L by the internal signal processing circuit are synthesized to produce a video signal of one screen. Is output as For example, a composite video signal (NTSC signal) output having an aspect ratio of 4: 3 is output by connecting screens having an aspect ratio of 8: 3 vertically.
[0080]
When synthesizing in the signal synthesizing circuit 75, the upper and lower screens are offset from each other in the left-right direction, whereby a display screen similar to that of FIG. 16 of the second embodiment is obtained on the monitor.
In other words, an indicator block is displayed in the upper half of the display screen that is the right-side shooting screen, and in black on the right end in the lower half that is the left-side shooting screen. This enhances the recognition that the upper half is on the right side and the lower half is on the left side. It is also easy to switch the display of the upper half and the lower half.
[0081]
According to this embodiment as well, safety can be confirmed at intersections with poor visibility, and a horizontally long screen can be obtained in each direction, so that the angle of view in the left and right direction (horizontal direction) can be widened.
[0082]
【The invention's effect】
As described above, the present invention An image of the range from the lateral direction of the vehicle to the forward direction In a vehicle camera that outputs an output screen image signal to be displayed on a monitor, two reflecting surfaces facing left and right outside are provided. Front end of vehicle And the two reflecting surfaces as the shooting range and the shooting direction of the vehicle Forward The camera is equipped with an imaging device that is directed rearward with respect to the direction, and the imaging device outputs the video signal by horizontally reversing the captured image, so that a special controller that performs independent left and right image reversal processing is unnecessary and inexpensive. It has the effect that it can be manufactured and is small in size.
[0083]
By arranging the two reflecting surfaces substantially symmetrically with respect to a plane parallel to the center plane that bisects the vehicle in the width direction, the widest shooting range is ensured on both the right and left sides.
In addition, by arranging the optical axis of the optical system of the imaging means to be substantially horizontal and passing through the approximate center of the top and bottom of the reflecting surface, the top and bottom are evenly imaged around the horizontal direction, and the area to be checked is easily and reliably imaged. The effect of entering the field of view is obtained.
Still further, by storing the photographing means and the mirror in the case so that the photographing means photographs the outside of the case through the window, maintenance management becomes easy even when installed in a bad environment outside the vehicle body.
[Brief description of the drawings]
FIG. 1 is an external perspective view showing a first embodiment of the present invention.
FIG. 2 is a horizontal sectional view of the first embodiment.
FIG. 3 is a view showing a mounting state of the embodiment.
FIG. 4 is a diagram illustrating an installation example of a monitor.
FIG. 5 is a diagram illustrating a connection between a camera device and a monitor.
FIG. 6 is a diagram for obtaining a positional relationship of elements of the camera device.
FIG. 7 is a diagram for obtaining a positional relationship of elements of the camera device.
FIG. 8 is a diagram illustrating an example of dimensions of a camera device.
FIG. 9 is an explanatory diagram showing the operation of the embodiment.
FIG. 10 is an explanatory diagram illustrating a photographing field according to an embodiment.
FIG. 11 is a diagram illustrating another example of attachment of the camera device.
FIG. 12 is a diagram showing a second embodiment.
FIG. 13 shows a mask.
FIG. 14 is an explanatory diagram showing a positional relationship between a CCD camera body and a mirror.
FIG. 15 is an explanatory diagram showing the operation of the second embodiment.
FIG. 16 is a diagram showing a monitor display example in the second embodiment.
FIG. 17 is a diagram showing a comparative example of the positional relationship between the CCD camera body and the mirror.
FIG. 18 is a diagram showing a captured image in a comparative example.
FIG. 19 is an explanatory diagram showing an operation in a comparative example.
FIG. 20 is a diagram showing a third embodiment.
FIG. 21 is an explanatory diagram showing a photographing field of view according to the third embodiment.
FIG. 22 is a diagram showing another example of a mask portion.
FIG. 23 is a diagram showing a fourth embodiment.
FIG. 24 is a diagram showing a first conventional example.
FIG. 25 is a diagram showing a captured image in the first conventional example.
FIG. 26 is a block diagram illustrating an example of a controller for image inversion.
FIG. 27 is an explanatory diagram showing processing in a controller.
FIG. 28 is a block diagram illustrating an example of another controller for image inversion.
FIG. 29 is an explanatory diagram showing processing in the controller.
FIG. 30 is a diagram showing a second conventional example.
FIG. 31 is a diagram illustrating a captured image when the boundary between left and right independent inversions is deviated.
[Explanation of symbols]
1, 1A, 1B, 1C Camera device
2, 2A, 2C case
3, 3A, 3C window
4, 4A transparent body
6 changeover switch
8 Monitor
10, 30, 50, 70R, 70L CCD camera body
11, 31, 51, 71 Lens housing
12 CCD element (two-dimensional image sensor)
13 Circuit board
14 Signal processing circuit (signal processing means)
15 Power supply circuit
20 V-shaped mirror
21, 22 Reflecting surface
32, 72 CCD element (two-dimensional image sensor)
32a Photosensitive surface
33, 73 Circuit board
40, 60 mirror
41, 42, 61, 62 Reflecting surface
47, 67, 68 mask
48UP, 48LW window
75 Signal synthesis circuit
80 CCD camera body
83, 84 Mirror
101, 201 Camera device
102 cases
103, 203 CCD camera body
104, 204 V-shaped mirror
110, 110A controller
111 line memory
112 monitor
113 T-flip flop
114 Up / Down counter
115 Random logic circuit
116 Latch circuit
BK indicator block
GAHR, GAHL shooting screen
GHR, GHL Reverse image
GR, GL, GAR, GAL Normal image
K dashboard
P Optical axis
Q Area that becomes blind spot
RS shooting field of view
S vehicle
X Camera line of sight

Claims (9)

A camera that is mounted on a vehicle and outputs an output screen image signal for displaying an image in a range from a lateral direction to a forward direction of the vehicle on a monitor, and has two reflecting surfaces on the left and right outer sides with respect to the vehicle forward direction. And a mirror connected at the front end of the vehicle ,
An imaging unit comprising a two-dimensional image sensor, an optical system, and a signal processing unit, outputting a video signal in which the two reflecting surfaces are set as an imaging range with the imaging direction set to the rear with respect to the vehicle forward direction, and the captured images are reversed horizontally A vehicle camera characterized by comprising:   2. The mirror according to claim 1, wherein two reflecting surfaces are substantially perpendicular to a horizontal plane and are substantially symmetrical with respect to a plane parallel to a central plane that bisects the vehicle in the width direction. The vehicle camera described.   3. The vehicle camera according to claim 1, wherein the photographing unit is disposed so that an optical axis of an optical system is substantially horizontal and passes through substantially the center of the two reflecting surfaces of the mirror.   The photographing means and the mirror are housed in a case, and the case is provided with transparent windows on the left and right side walls corresponding to the two reflecting surfaces of the mirror, and the photographing means is disposed in the case via the reflecting surface and the window. 4. The vehicular camera according to claim 1, wherein the vehicular camera is configured to photograph the outside.   5. The vehicle camera according to claim 4, wherein the photographing means and the mirror are disposed on a substantially central plane that divides the width of the vehicle in the vicinity of the front end of the vehicle.   5. The vehicle camera according to claim 4, wherein the photographing means and the mirror are disposed in front of the driver's seat near the front end of the vehicle. A camera that is mounted on a vehicle and outputs an output screen image signal for displaying an image in a range from a lateral direction to a forward direction of the vehicle on a monitor, and has two reflecting surfaces on the left and right outer sides with respect to the vehicle forward direction. And a mirror connected at the front end of the vehicle ,
An imaging unit comprising a two-dimensional image sensor, an optical system, and a signal processing unit, outputting a video signal in which the two reflecting surfaces are set as an imaging range with the imaging direction set to the rear with respect to the vehicle forward direction, and the captured images are reversed horizontally And a case for storing the photographing means and a mirror,
The case is provided with transparent windows on the left and right side walls corresponding to the two reflecting surfaces of the mirror, and the photographing means photographs the outside of the case through the reflecting surface and the window,
The mirrors are arranged substantially symmetrically with respect to a plane parallel to a central plane that divides the vehicle into two in the width direction, each of which has two reflecting surfaces that are flat and substantially perpendicular to a horizontal plane,
The photographing means is arranged so that the optical axis of the optical system is substantially horizontal and passes through the substantially upper and lower centers of the two reflecting surfaces of the mirror, the radius of the outer diameter of the optical system is R, and each surface of the reflecting surface is The angle formed by the normal is 2 · θm, and the distance between the reflecting surface and the optical system is d.
R · tan (90 ° -2 · θm) ≦ d
≦ R ・ tan (90 ° −2 ・ θm) +2 (mm)
A vehicle camera characterized by the fact that A camera that is mounted on a vehicle and outputs an output screen image signal for displaying an image in a range from a lateral direction to a forward direction of the vehicle on a monitor,
A mirror that faces the left and right outer sides of the two reflecting surfaces with respect to the vehicle forward direction, and is connected at an end on the front side of the vehicle ;
An imaging unit comprising a two-dimensional image sensor, an optical system, and a signal processing unit, outputting a video signal in which the two reflecting surfaces are set as an imaging range with the imaging direction set to the rear with respect to the vehicle forward direction, and the captured images are reversed horizontally And a case for storing the photographing means and a mirror,
The case is provided with transparent windows on the left and right side walls corresponding to the two reflecting surfaces of the mirror, and the photographing means photographs the outside of the case through the reflecting surface and the window,
The mirrors are arranged substantially symmetrically with respect to a plane parallel to a central plane that divides the vehicle into two in the width direction, each of which has two reflecting surfaces that are flat and substantially perpendicular to a horizontal plane,
The imaging means is arranged so that the optical axis of the optical system is substantially horizontal and passes through the upper and lower centers of the two reflecting surfaces of the mirror, the field angle of the imaging means is θ0, and the radius of the entrance pupil of the optical system is r. , The angle between the normals of each surface of the reflecting surface is 2 · θm, the distance between the reflecting surface and the optical system is d, and the horizontal length of one reflecting surface is L,

A vehicle camera characterized by the fact that A camera that is mounted on a vehicle and outputs an output screen image signal for displaying an image in a range from a lateral direction to a forward direction of the vehicle on a monitor,
A mirror that faces the left and right outer sides of the two reflecting surfaces with respect to the vehicle forward direction, and is connected at an end on the front side of the vehicle ;
An imaging unit comprising a two-dimensional image sensor, an optical system, and a signal processing unit, outputting a video signal in which the two reflecting surfaces are set as an imaging range with the imaging direction set to the rear with respect to the vehicle forward direction, and the captured images are reversed horizontally And a case for storing the photographing means and a mirror,
The case is provided with transparent windows on the left and right side walls corresponding to the two reflecting surfaces of the mirror, and the photographing means photographs the outside of the case through the reflecting surface and the window,
The mirrors are arranged substantially symmetrically with respect to a plane parallel to a central plane that divides the vehicle into two in the width direction, each of which has two reflecting surfaces that are flat and substantially perpendicular to a horizontal plane,
The photographing means is arranged so that the optical axis of the optical system is substantially horizontal and passes through the substantially upper and lower centers of the two reflecting surfaces of the mirror, the field angle of the photographing means is θ0, and the normal of each surface of the reflecting surface is The angle formed is 2 · θm.
45 ° −θ0 / 4 ≦ θm ≦ 50 ° −θ0 / 4
A vehicle camera characterized by the fact that

Images