JP4096437B2 - Light valve positioning method - Google Patents

Description

【０２２４】
ここで、カメラＮｏ．１の撮像領域６１１の中心（中心点）をフォーカス調整された液晶ライトバルブ２５に光学ブロック２０を介して投影したときのＸ座標を上記（１）式中のＸ１、Ｙ座標を上記（１）式中のＹ１とする。
【０２２５】
同様に、カメラＮｏ．２の撮像領域６２１の中心をフォーカス調整された液晶ライトバルブ２５に光学ブロック２０を介して投影したときのＸ座標を上記（１）式中のＸ２、Ｙ座標を上記（１）式中のＹ２とする。
【０２２６】
同様に、カメラＮｏ．３の撮像領域６３１の中心をフォーカス調整された液晶ライトバルブ２５に光学ブロック２０を介して投影したときのＸ座標を上記（１）式中のＸ３、Ｙ座標を上記（１）式中のＹ３とする。
【０２２７】
同様に、カメラＮｏ．４の撮像領域６４１の中心をフォーカス調整された液晶ライトバルブ２５に光学ブロック２０を介して投影したときのＸ座標を上記（１）式中のＸ４、Ｙ座標を上記（１）式中のＹ４とする。
【０２２８】
なお、前記Ｘ１、Ｙ１、Ｘ２、Ｙ２、Ｘ３、Ｙ３、Ｘ４およびＹ４は、それぞれ、対応するカメラの位置で決定されている。
【０２２９】
前記Ｘ１、Ｘ２、Ｘ３およびＸ４と、前記Ｚ１、Ｚ２、Ｚ３およびＺ４とを下記（２）式に代入して、液晶ライトバルブ２５のＨ方向の移動量（角度）Ｈｄを求める。なお、図５中の矢印（Ｈ）の方向が正の方向である。
【０２３０】
【数２】

【０２３１】
また、前記Ｈｄと、前記Ｙ１、Ｙ２、Ｙ３およびＹ４と、前記Ｚ１、Ｚ２、Ｚ３およびＺ４とを下記（３）式に代入して、液晶ライトバルブ２５のＶ方向の移動量（角度）Ｖｄを求める。なお、図５中の矢印（Ｖ）の方向が正の方向である。
【０２３２】
【数３】

【０２３３】
次いで、３軸テーブル８により、液晶ライトバルブ２５を、Ｈ方向に前記ステップＳ１０９で得られた角度Ｈｄ回転させ、また、Ｖ方向に角度Ｖｄ回転させる（ステップＳ１１０）。
【０２３４】
ここで、３軸テーブル８により、液晶ライトバルブ２５をＺ軸に沿って前記ステップＳ１０９で得られたフォーカス位置ＺＰに移動させた場合には、４つの撮像領域６１１〜６４１の処理領域５５０内の画像の状態が、それぞれ、図４２（ｄ）に示す目的の状態に近づく（目的の状態と一致する場合も含む）が、すなわち、粗く４隅のフォーカスが合うが、この動作は省略される（液晶ライトバルブ２５のＺ軸方向の調整は、後述する微調整においてのみ行えばよい）。なお、この動作を前記粗調整において行ってもよいことは、言うまでもない。
【０２３５】
また、前記ステップＳ１１０では、必要に応じて、３軸テーブル９により、液晶ライトバルブ２５をＸ軸方向、Ｙ軸方向に所定量移動させる。
【０２３６】
このステップＳ１１０で粗調整が終了する。
【０２３７】
次いで、微調整における画像データ取得のための液晶ライトバルブ２５のＺ軸方向移動範囲を設定する（ステップＳ１１１）。
【０２３８】
このステップＳ１１１では、前記ステップＳ１０９で得られたフォーカス位置ＺＰから、ダイクロイックプリズム２１から離間する方向に所定量（所定距離）離間した位置を後述するステップＳ１１２の微調整における画像データ取得開始位置（Ｚ軸方向設定位置）として設定するとともに、前記フォーカス位置ＺＰから、ダイクロイックプリズム２１に接近する方向に所定量（所定距離）離間した位置を後述するステップＳ１１８の微調整における画像データ取得終了位置として設定する。
【０２３９】
前記所定量は、それぞれ、例えば、図４１に示すＺ軸方向の距離Ｌ３の１／２の値、または距離Ｌ３の１／２より大きい所定の値に予め設定されている。この所定量は、例えば、実験的に求められる。
【０２４０】
なお、前記画像データ取得開始位置は、液晶ライトバルブ２５が画像データ取得開始位置に位置しているとき、フォーカスが合わないように設定されればよいが、液晶ライトバルブ２５が画像データ取得開始位置に位置しているとき、フォーカスが合わず、かつ、撮像領域６１１〜６４１内の液晶ライトバルブ２５の画素に対応する部分の輝度と、前記画素の間の部分に対応する部分の輝度とに差がでるように設定されるのが好ましい。
【０２４１】
また、前記画像データ取得終了位置は、液晶ライトバルブ２５が画像データ取得終了位置に位置しているとき、フォーカスが合わないように設定されればよいが、液晶ライトバルブ２５が画像データ取得終了位置に位置しているとき、フォーカスが合わず、かつ、撮像領域６１１〜６４１内の液晶ライトバルブ２５の画素に対応する部分の輝度と、前記画素の間の部分に対応する部分の輝度とに差がでるように設定されるのが好ましい。
【０２４２】
次いで、３軸テーブル８により、液晶ライトバルブ２５をＺ軸に沿って、前記微調整における画像データ取得開始位置（Ｚ軸方向設定位置）へ移動させる（ステップＳ１１２）。
【０２４３】
次いで、カメラＮｏ．１で撮像し、撮像領域６１１の画像データをメモリー４に記憶する（ステップＳ１１３）。
【０２４４】
次いで、カメラＮｏ．２で撮像し、撮像領域６２１の画像データをメモリー４に記憶する（ステップＳ１１４）。
【０２４５】
次いで、カメラＮｏ．３で撮像し、撮像領域６３１の画像データをメモリー４に記憶する（ステップＳ１１５）。
【０２４６】
次いで、カメラＮｏ．４で撮像し、撮像領域６４１の画像データをメモリー４に記憶する（ステップＳ１１６）。
【０２４７】
次いで、前述したように、分散値取得処理（図８および図９に示すサブルーチン）を実行し（ステップＳ１０ａ）、カメラＮｏ．１〜カメラＮｏ．４で撮像した各画像（電子画像）について、それぞれ、Ｙ軸方向成分（縦方向成分）の分散値Ｖｖと、Ｘ軸方向成分（横方向成分）の分散値Ｖｈとを取得する。
【０２４８】
次いで、図４０に示すように、３軸テーブル８により、液晶ライトバルブ２５をＺ軸方向に一定量（例えば、１０μm ）移動させる（ステップＳ１１７）。
【０２４９】
前述したように、微調整における画像データ取得開始位置が前記ステップＳ１０９で得られたフォーカス位置ＺＰよりダイクロイックプリズム２１に遠い側の所定位置に設定されているので、このステップＳ１１７では、液晶ライトバルブ２５をダイクロイックプリズム２１に接近する方向（図４０中左側）に移動させる。
【０２５０】
次いで、液晶ライトバルブ２５が微調整における画像データ取得終了位置に到達したか否かを判断する（ステップＳ１１８）。
【０２５１】
前記ステップＳ１１８において、液晶ライトバルブ２５が画像データ取得終了位置に到達していないと判断した場合には、ステップＳ１１３に戻り、再度、ステップＳ１１３〜ステップＳ１１８を実行する。これにより、液晶ライトバルブ２５を前回の位置からＺ軸方向にＬ１移動させてカメラＮｏ．１〜カメラＮｏ．４で撮像した各画像について、それぞれ、Ｙ軸方向成分の分散値Ｖｖと、Ｘ軸方向成分の分散値Ｖｈとを取得することができる。
【０２５２】
また、前記ステップＳ１１８において、液晶ライトバルブ２５が画像データ取得終了位置に到達したと判断した場合には、前述した粗調整の場合と同様にして、微調整における前記ステップＳ１０ａで取得した分散値に基づいて、微調整におけるＺ軸方向のフォーカス位置（合焦位置）ＺＰと、Ｈ方向の移動量（角度）Ｈｄと、Ｖ方向の移動量（角度）Ｖｄとをそれぞれ求める（ステップＳ１１９）。
【０２５３】
次いで、３軸テーブル８により、液晶ライトバルブ２５をＺ軸に沿って前記ステップＳ１１９で得られたフォーカス位置ＺＰに移動させ、また、Ｈ方向に角度Ｈｄ回転させ、また、Ｖ方向に角度Ｖｄ回転させる（ステップＳ１２０）。
【０２５４】
これにより、前記ステップＳ１１０において液晶ライトバルブ２５をＺ軸に沿って前記ステップＳ１０９で得られたフォーカス位置ＺＰに移動させた場合に対し、４つの撮像領域６１１〜６４１の処理領域５５０内の画像の状態が、それぞれ、図４２（ｄ）に示す目的の状態にさらに近づく（目的の状態と一致する場合も含む）。すなわち、実質的に４隅のフォーカスが合う。
【０２５５】
また、前記ステップＳ１２０では、必要に応じて、３軸テーブル９により、液晶ライトバルブ２５をＸ軸方向、Ｙ軸方向に所定量移動させる。
【０２５６】
このステップＳ１２０で微調整が終了、すなわち、フォーカス調整が終了する。
【０２５７】
なお、本発明では、フォーカス調整における粗調整や、微調整を前述した方法と異なる方法で行ってもよい。前述した方法と異なる方法としては、例えば、画像全体の分散値を求めてフォーカス調整を行う方法や、コントラストを測定してフォーカス調整を行う方法等が挙げられる。
【０２５８】
但し、フォーカス調整における粗調整と微調整のうちの一方、特に、微調整を前述した方法で行うのが好ましく、フォーカス調整における粗調整と微調整の両方を前述した方法で行うのがより好ましい。
【０２５９】
また、前記実施例では、フォーカス調整における調整の回数が２回（粗調整と微調整）に設定されているが、本発明では、フォーカス調整における調整の回数は、２回に限らず、１回、または３回以上であってもよい。
【０２６０】
但し、フォーカス調整における調整の回数は、２回以上が好ましく、２〜４回程度がより好ましい。
【０２６１】
フォーカス調整において、その調整を２回以上行うと、フォーカス調整の精度を向上させることができる。
【０２６２】
また、フォーカス調整における調整の回数を２回以上にする場合、後の調整ほど、撮像時の液晶ライトバルブ２５のＺ軸方向における位置の間隔（画像データを取得する際、液晶ライトバルブ２５を次の撮像時の位置に移動させるときのその移動量）を小さくするのが好ましい。
【０２６３】
これにより、フォーカス調整に要する時間を短縮しつつ、フォーカス調整の精度を向上させることができる。
【０２６４】
また、本発明では、画像データを取得する際の液晶ライトバルブ２５の移動方向を、ダイクロイックプリズム２１から離間する方向（図４０中右側）としてもよい。すなわち、画像データ取得開始位置と画像データ取得終了位置を前記実施例と逆にしてもよい。
【０２６５】
また、本発明では、粗調整と微調整とで、画像データを取得する際の液晶ライトバルブ２５の移動方向が異なっていてもよい。
【０２６６】
また、前記実施例では、Ａ行に属する行５７０や、Ｃ列に属する列５６０を選択する場合、積算値の大きい方から所定数のラインを選択するようになっているが、本発明では、これに限らず、例えば、所定のしきい値を設定し、このしいき値以上の行や列を選択するように構成してもよい。
【０２６７】
但し、前記実施例のように積算値の大きい方から所定数のラインを選択するよう構成するのが好ましい。この場合には、特に、照明ムラや画像ムラがあったとしても、精度良くフォーカス調整することができる。
【０２６８】
フォーカス調整終了後、液晶ライトバルブ２５の作動（駆動）を維持し、その所定の画素をオンし、スクリーン２上に図４４に示す前述した位置調整用の投影画像１４１を投影する（ステップＳ１５０）。
【０２６９】
すなわち、ステップＳ１５０により、図１に示すように、照明装置７１〜７４から出射し、液晶ライトバルブ２５の画素のうちのオンした画素を透過した光がスクリーン２上の投影領域１１０に投影される。
【０２７０】
このステップＳ１５０後、位置調整（アライメント調整）へ移行する。以下、代表的に緑色用の液晶ライトバルブ２５の位置調整（アライメント調整）を説明する。
【０２７１】
図１０、１３〜１８は、位置調整（アライメント調整）における位置決め装置１の制御手段３の制御動作を示すフローチャートである。以下、このフローチャートに基づいて説明する。
【０２７２】
以下のアライメント調整の説明において、投影領域１１０を移動させるとは、３軸テーブル９で液晶ライトバルブ２５をＸ軸方向およびＹ軸方向に移動させることにより、投影領域１１０を移動させることを意味する。また、投影領域１１０を回転させるとは、３軸テーブル９で液晶ライトバルブ２５をＷ方向（Ｚ軸の回り）に回転させることにより、投影領域１１０を回転させることを意味する。
【０２７３】
また、以下のアライメント調整の説明において、図１９〜２５中左右方向は、液晶ライトバルブ２５のＸ軸方向に対応し、図１９〜２５中上下方向は、液晶ライトバルブ２５のＹ軸方向に対応している。
【０２７４】
以下の位置調整を行う前に、あらかじめ、メモリー４に、図１１に示すような、投影領域１１０の各角部１１１ａ、１１１ｂ、１１１ｃおよび１１１ｄを含む部分に対応した４つのパターンＡ１、Ｂ１、Ｃ１およびＤ１の画像データ（輝度データ）を記憶しておく。さらに、あらかじめ、図１２に示すような、投影領域１１０の図６中左側のＹ軸方向の辺１１３ａを含む部分に対応したパターンＨ１、および、投影領域１１０の図６中下側のＸ軸方向の辺１１４ａを含む部分に対応したパターンＶ１の画像データを記憶しておく。
【０２７５】
各パターンＡ１、Ｂ１、Ｃ１およびＤ１中には、それぞれ、位置１２１、１２２、１２３および１２４があらかじめ設定されている。これら位置１２１、１２２、１２３および１２４は、それぞれ、投影領域１１０のエッジ（頂点）１１２ａ、１１２ｂ、１１２ｃ、１１２ｄの位置に対応している。また、パターンＨ１およびＶ１には、それぞれ位置１２９ａおよび１２９ｂがあらかじめ設定されている。なお、これら位置１２９ａおよび１２９ｂは、投影領域１１０の対応する辺１１３ａおよび１１４ａ上に重なるように位置している。
【０２７６】
なお、これらのパターンをあらかじめメモリー４に記憶しておかずに、以下の位置調整において必要に応じ、位置決め装置１に接続されている図示しない外部記憶装置（例えば、フロッピーディスク、ハードディスク、光磁気ディスクなど）から、適宜メモリー４に読み込んでもよい。
【０２７７】
なお、以下の位置調整を説明するに先立って、以下の位置調整中で適宜行われるパターンマッチング（パターンマッチング法）について、まず説明する。
【０２７８】
パターンマッチングでは、例えばカメラＮｏ．１、２、３、４で撮影され、メモリ４に取り込まれた画像データ（被検索データ）中に、パターンＡ１、Ｂ１、Ｃ１、Ｄ１、Ｈ１、Ｖ１等の特定のパターン（検索パターン）が存在するか否かを検索する。
【０２７９】
そして、かかる検索パターンが存在しない場合には、かかる検索パターンは被検索データ中に存在しないと判別される。
【０２８０】
一方、かかる検索パターンが存在する場合には、かかる検索パターンは被検索データ中に存在すると判別される。また、このとき、撮像した画像（被検索データ）中の所定領域と、検索パターンとが一致したときの位置（例えば位置１２１〜１２４、１２９ａ、１２９ｂ等）の座標（Ｘ座標、Ｙ座標）を得る。この座標（位置）をその後の処理で必要としない場合は、かかる座標は、得なくてもよい。
【０２８１】
ここで、パターンマッチング中において、「検索パターンが存在する」とは、検索パターンと完全に合致するパターンが、被検索データ中に存在するという意ではなく、検索パターンとの一致度（認識率）が一定値（しきい値）以上のパターンが存在することをいう。
【０２８２】
この値（しきい値）は、位置決め装置１の置かれている環境等、種々の条件により好ましい値は異なるが、８０％以上に設定することが好ましく、９０％以上に設定することがより好ましい。しきい値を前記の値に設定すると、パターンマッチングをより高い精度で行うことができる。
【０２８３】
なお、検索パターンが被検索データ中に存在する旨の結果を出力あるいは返却する際に、必要に応じ、かかる一致度を返却または出力してもよい。
【０２８４】
図１０に示すように、位置調整（アライメント調整）では、まず、粗調整を行い（Ｓ３００）、次いで、微調整（Ｓ３５０）を行う。
【０２８５】
まず、ステップＳ３００の粗調整について説明する。
【０２８６】
ステップＳ３００の粗調整では、第１の処理（処理Ｓ３０Ａ）と、第２の処理（処理Ｓ３０Ｂ）と、第３の処理（処理Ｓ３０Ｃ）と、第４の処理（処理Ｓ３０Ｄ）と、第５の処理（処理Ｓ３０Ｅ）と、第６の処理（処理Ｓ３０Ｆ）と、第７の処理（処理Ｓ３０Ｇ）と、第８の処理（処理Ｓ３０Ｈ）とを行う。以下、図１３〜１６、１９〜２４に基づいて、各処理を、ステップごとに詳細に説明する。
【０２８７】
［処理Ｓ３０Ａ］第１の処理は、ステップＳ３０１〜Ｓ３０３とパターンＣ導入処理（処理Ｓ９０ａ）とで構成される。
【０２８８】
ステップＳ３０１〜Ｓ３０３を実行することにより、投影領域１１０の角部１１１ｃが撮像領域（目的領域）６３１内に存在するか否かを検出することができる。また、角部１１１ｃが撮像領域６３１内に存在しない場合には、パターンＣ導入処理（処理Ｓ９０ａ）を実行することにより、角部１１１ｃを撮像領域６３１内に導入することができる。
【０２８９】
［ステップＳ３０１］まず、カメラＮｏ．３（カメラ６３）で撮像し、撮像領域６３１の画像データをメモリー４に記憶する。
【０２９０】
［ステップＳ３０２］次に、前記ステップＳ３０１でメモリー４に記憶した画像データに対して、パターンＣ１を検索パターンとして、パターンマッチングを行う。
【０２９１】
［ステップＳ３０３］次に、パターンマッチングを行った結果、前記ステップＳ３０１でメモリー４に記憶した画像データにパターンＣ１が存在する場合、すなわち図１９（Ａ１）に示すように、撮像領域６３１内に角部１１１ｃが存在する場合には、第２の処理（処理Ｓ３０Ｂ）すなわちステップＳ３０４を行い、存在しない場合には、パターンＣ導入処理（処理Ｓ９０ａ）を実行する。
【０２９２】
なお、ここで、「撮像領域６３１内に角部１１１ｃが存在しない」とは、パターンマッチングで、角部１１１ｃが存在しないという結果が得られたという意である。以下の説明において、パターンマッチングの結果に基づき本ステップと同様の判断を行う場合にも、これと同様のことが言える。
【０２９３】
［処理Ｓ９０ａ］パターンＣ導入処理は、図１６に示すように、ステップＳ９０１〜Ｓ９１０で構成される。
【０２９４】
このパターンＣ導入処理を実行することにより、角部１１１ｃを撮像領域６３１内に入れるもしくは近づけることができる。さらには、この処理を実行することにより、投影領域１１０と撮像領域６３１との相対的な位置関係が分かる。
【０２９５】
［ステップＳ９０１］まず、前記ステップＳ３０１でメモリー４に記憶した画像データに対して、パターンＨ１を検索パターンとして、パターンマッチングを行う。
【０２９６】
［ステップＳ９０２］次に、パターンマッチングを行った結果、前記ステップＳ３０１でメモリー４に記憶した画像データにパターンＨ１が存在する場合、すなわち図１９（Ａ２）に示すように、撮像領域６３１内に投影領域１１０のＹ軸方向の辺１１３ａが存在する場合には、ステップＳ９０３を行い、存在しない場合には、ステップＳ９０４を実行する。
【０２９７】
［ステップＳ９０３］次に、投影領域１１０を、図１９中上方に移動（変位）させる。このときの移動量は、例えば、撮像領域６３１のＹ軸方向の長さｎの１／３に相当する量である。
【０２９８】
これにより、図１９（Ｂ２）に示すように、投影領域１１０の角部１１１ｃが撮像領域６３１内に入る。もしくは、例えば角部１１１ｃが撮像領域６３１からｎ／３より離間した位置に存在する場合のように、投影領域１１０の角部１１１ｃが撮像領域６３１から遠い場合には、投影領域１１０の角部１１１ｃが撮像領域６３１に近づく。
【０２９９】
その後、ステップＳ３０１へ戻る。
【０３００】
なお、本ステップにおいて、投影領域１１０の移動量は、アライメントを調整する際の諸条件に応じて、任意の値に設定することが可能である。これは、以下のステップにおいて、本ステップと同様の処理を行う場合（例えば、ステップＳ９０６、ステップＳ９０９、ステップＳ９１０など）にも言える。
【０３０１】
［ステップＳ９０４］次に、前記ステップＳ３０１でメモリー４に記憶した画像データに対して、パターンＶ１を検索パターンとして、パターンマッチングを行う。
【０３０２】
［ステップＳ９０５］次に、パターンマッチングを行った結果、前記ステップＳ３０１でメモリー４に記憶した画像データにパターンＶ１が存在する場合、すなわち図１９（Ａ３）に示すように、撮像領域６３１内に投影領域１１０のＸ軸方向の辺１１４ａが存在する場合には、ステップＳ９０６を行い、存在しない場合には、ステップＳ９０７を実行する。
【０３０３】
［ステップＳ９０６］次に、投影領域１１０を、図１９中右方向に移動させる。このときの移動量は、例えば、撮像領域６３１のＸ軸方向の長さｍの１／３に相当する量である。
【０３０４】
これにより、図１９（Ｂ３）に示すように、投影領域１１０の角部１１１ｃが撮像領域６３１内に入る。もしくは、例えば角部１１１ｃが撮像領域６３１からｍ／３より離間した位置に存在する場合のように、投影領域１１０の角部１１１ｃが撮像領域６３１から遠い場合には、投影領域１１０の角部１１１ｃが撮像領域６３１に近づく。
【０３０５】
その後、ステップＳ３０１へ戻る。
【０３０６】
［ステップＳ９０７］次に、前記ステップＳ３０１でメモリー４に記憶した画像データに対して、かかる画像データ全体の輝度、すなわち撮像領域６３１内の明るさを求める。
【０３０７】
［ステップＳ９０８］次に、輝度を求めた結果、かかる輝度がしきい値未満の場合（撮像領域６３１内の明るさがしきい値未満の場合）、すなわち図２０（Ａ４）に示すように、撮像領域６３１中に投影領域１１０の角部１１１ｃ、辺１１３ａ、１１４ａのいずれも存在しない場合には、ステップＳ９０９を実行する。一方、輝度が一定値以上の場合（撮像領域６３１内の明るさがしきい値以上の場合）、すなわち図２０（Ａ５）に示すように、撮像領域６３１が投影領域１１０内に包含されている場合には、ステップＳ９１０を実行する。
【０３０８】
なお、このしきい値は、撮像領域６３１中に投影領域１１０の角部１１１ｃ、辺１１３ａ、１１４ａのいずれも存在しない場合の輝度よりも十分高く、かつ、撮像領域６３１が投影領域１１０内に包含されている場合の輝度よりも十分低く設定されている。
【０３０９】
［ステップＳ９０９］次に、投影領域１１０を、図２０中左下方向に移動させる。このとき図２０中下方向への移動量は、例えば、撮像領域６３１のＹ軸方向の長さｎの１／３に相当する量であり、図１９中左方向への移動量は、例えば、撮像領域６３１のＸ軸方向の長さｍの１／３に相当する量である。
【０３１０】
これにより、図２０（Ｂ４）に示すように、投影領域１１０の角部１１１ｃが撮像領域６３１内に入る。もしくは、投影領域１１０の角部１１１ｃが、かかる移動量に相当する距離より、撮像領域６３１から離間していた場合には、投影領域１１０の角部１１１ｃが撮像領域６３１に近づく。
【０３１１】
その後、ステップＳ３０１へ戻る。
【０３１２】
［ステップＳ９１０］次に、投影領域１１０を、図２０中右上方向に移動させる。このとき図２０中上方向への移動量は、例えば、撮像領域６３１のＹ軸方向の長さｎの１／３に相当する量であり、図２０中右方向への移動量は、例えば、撮像領域６３１のＸ軸方向の長さｍの１／３に相当する量である。
【０３１３】
これにより、図２０（Ｂ５）に示すように、投影領域１１０の角部１１１ｃが撮像領域６３１内に入る。もしくは、投影領域１１０の角部１１１ｃが、かかる移動量に相当する距離より、撮像領域６３１から離間していた場合には、投影領域１１０の角部１１１ｃが撮像領域６３１に近づく。
【０３１４】
その後、ステップＳ３０１へ戻る。
【０３１５】
なお、角部１１１ｃが撮像領域６３１から大きく離間している場合のように、１回のパターンＣ導入処理で角部１１１ｃを撮像領域６３１内に入れることができない場合でも、パターンＣ導入処理を１回実行する度に角部１１１ｃを撮像領域６３１に近づけることができるので、パターンＣ導入処理を複数回実行することにより、最終的に角部１１１ｃを撮像領域６３１内に入れることができる。
【０３１６】
［処理Ｓ３０Ｂ］第２の処理は、ステップＳ３０４、Ｓ３０５で構成される。
【０３１７】
この第２の処理を実行することにより、角部１１１ｃを撮像領域６３１の中心１２５ｃに合致させることができる。
【０３１８】
［ステップＳ３０４］まず、前記ステップＳ３０２における最後のパターンマッチングで得られた位置１２３に基づいて、投影領域１１０のエッジ１１２ｃを撮像領域６３１の中心１２５ｃに移動させるための、投影領域１１０のＸ軸方向およびＹ軸方向の移動量を求める。
【０３１９】
これは、前述したように、得られた位置１２３の座標は、エッジ１１２ｃの座標に対応している、すなわち、位置１２３の座標は、エッジ１１２ｃの座標を表しているので、位置１２３の座標と中心１２５ｃとの座標から、投影領域１１０の移動量を求めることができる。
【０３２０】
［ステップＳ３０５］次に、前記ステップＳ３０４で求めた投影領域１１０のＸ軸方向およびＹ軸方向の移動量に基づいて、投影領域１１０を移動させる。
【０３２１】
これにより、図１９（Ｂ１）に示すように、投影領域１１０の角部１１１ｃが、撮像領域６３１の中心１２５ｃに合致する。
【０３２２】
以下に説明する第３〜第５の処理（処理Ｓ３０Ｃ〜Ｓ３０Ｅ）では、撮像領域６１１と撮像領域６３１とを基準として位置合わせを行う。すなわち、投影領域１１０のＹ軸方向、換言すれば、液晶ライトバルブ２５のＹ軸方向に重きを置いて位置合わせを行う。
【０３２３】
［処理Ｓ３０Ｃ］第３の処理は、ステップＳ３０６〜Ｓ３１０とパターンＡ導入処理（処理Ｓ９０ｂ）とで構成される。
【０３２４】
上記第１の処理および第２の処理を実行することにより、投影領域１１０の角部１１１ｃを撮像領域６３１内に導入し、さらには角部１１１ｃを撮像領域６３１の中心１２５ｃに合致させることができる。
【０３２５】
しかし、かかる処理を行った後でも、図２１（Ａ６）に示すように、辺１１３ａが撮像領域６３１の中心１２５ｃと撮像領域６１１の中心１２５ａとを結ぶ線に対して大きく傾いている場合には、角部１１１ａが撮像領域６１１内に入っていない場合がある。
【０３２６】
このような場合でも、この第３の処理を実行することにより、角部１１１ａを撮像領域６１１内に導入することができる。
【０３２７】
なお、以下のステップＳ３０８を実行するに先だって、後述するステップＳ９２１で投影領域１１０の移動量を算出するために必要な変数Ｉに、あらかじめ０を代入しておく。
【０３２８】
［ステップＳ３０６］まず、カメラＮｏ．３（カメラ６３）で撮像し、撮像領域６３１の画像データをメモリー４に記憶する。
【０３２９】
［ステップＳ３０７］次に、前記ステップＳ３０６でメモリー４に記憶した画像データに対して、パターンＣ１を検索パターンとして、パターンマッチングを行う。
【０３３０】
［ステップＳ３０８］次に、カメラＮｏ．１（カメラ６１）で撮像し、撮像領域６１１の画像データをメモリー４に記憶する。
【０３３１】
［ステップＳ３０９］次に、前記ステップＳ３０８でメモリー４に記憶した画像データに対して、パターンＡ１を検索パターンとして、パターンマッチングを行う。
【０３３２】
［ステップＳ３１０］次に、パターンマッチングを行った結果、前記ステップＳ３０８でメモリー４に記憶した画像データにパターンＡ１が存在しない場合、すなわち図２１（Ａ６）に示すように、撮像領域６１１内に角部１１１ａが存在しない場合には、パターンＡ導入処理（処理Ｓ９０ｂ）を実行する。一方、パターンＡ１が存在する場合には、第４の処理（処理Ｓ３０Ｄ）すなわちステップＳ３１１を実行する。
【０３３３】
［処理Ｓ９０ｂ］パターンＡ導入処理は、ステップＳ９２１、Ｓ９２２とで構成される。
【０３３４】
このパターンＡ導入処理を所定回数実行することにより、角部１１１ａを撮像領域６１１内に導入することができる。
【０３３５】
［ステップＳ９２１］まず、次のステップＳ９２２で投影領域１１０を移動させる際の移動先のエッジ１１２ｃの位置（座標）を求める。これは、例えば次の式で求めることができる。この式は、Ｉの値に対応したエッジ１１２ｃの座標を与える。なお、前述したように、ｎは、撮像領域６３１のＹ軸方向の長さであり、ｍは、撮像領域６３１のＸ軸方向の長さである。
【０３３６】
Ｘ軸方向の位置 ＝ ＩＤＯＵ＿Ｘ１ ＋ （Ｉ ｍｏｄ ３）＊（ｍ）
（ここで、（Ｉ ｍｏｄ ３）とは、Ｉを３で割ったときの余りを求めることを意味する）
Ｙ軸方向の位置 ＝ ＩＤＯＵ＿Ｙ１ ＋ （Ｉ／３）＊（ｎ／２） （なお、得られた移動量の小数点以下は切り捨てる）
ここで、定数ＩＤＯＵ＿Ｘ１およびＩＤＯＵ＿Ｙ１は、Ｉ＝０のときの、次のステップＳ９２２におけるエッジ１１２ｃの移動先の座標に対応している。
【０３３７】
これら定数ＩＤＯＵ＿Ｘ１およびＩＤＯＵ＿Ｙ１としては、Ｉ＝０のときの移動後のエッジ１１２ｃの位置が、撮像領域６３１の中心１２５ｃよりも図２１中左上に来るような値が好ましい。これにより、エッジ１１２ａを効率よく撮像領域６１１内に導入することができる。
【０３３８】
［ステップＳ９２２］次に、前記ステップＳ９２１で求めたエッジ１１２ｃの移動先の位置に、エッジ１１２ｃが来るように、投影領域１１０を移動させる。
【０３３９】
これにより、図２１（Ｂ６１）〜（Ｂ６４）および図２２（Ｂ６５）〜（Ｂ６９）に示すように、Ｉが所定の値になった場合に、エッジ１１２ａが、撮像領域６１１内に入る。
【０３４０】
なお、図２１の（Ｂ６１）はＩ＝０のときの投影領域１１０の位置を、（Ｂ６２）はＩ＝１のときの投影領域１１０の位置を、（Ｂ６３）はＩ＝２のときの投影領域１１０の位置を、（Ｂ６４）はＩ＝３のときの投影領域１１０の位置を、図２２の（Ｂ６５）はＩ＝４のときの投影領域１１０の位置を、（Ｂ６６）はＩ＝５のときの投影領域１１０の位置を、（Ｂ６７）はＩ＝６のときの投影領域１１０の位置を、（Ｂ６８）はＩ＝７のときの投影領域１１０の位置を、（Ｂ６９）はＩ＝８のときの投影領域１１０の位置をそれぞれ表している。
【０３４１】
なお、図２１および図２２に示す例では、Ｉ＝８となったときに、エッジ１１２ａが、撮像領域６１１内に入る。
【０３４２】
その後、ステップＳ３０８へ戻る。そのとき、Ｉに１を加える。
【０３４３】
このように、Ｉの値を変化させつつパターンＡ導入処理（処理Ｓ９０ｂ）を所定回数実行することにより、エッジ１１２ａを撮像領域６１１内に入れることができる。
【０３４４】
なお、前記ステップＳ９２１において、エッジ１１２ｃのＸ軸方向の位置およびＹ軸方向の位置は、同一の変数Ｉによりそれぞれを求めているが、Ｘ軸およびＹ軸に対応した変数をそれぞれ用意し、Ｘ軸方向の位置およびＹ軸方向の位置を、これら用意した変数からそれぞれ独立に求めてもよい。
【０３４５】
なお、前記ステップＳ９２１において、エッジ１１２ｃのＸ軸方向の位置およびＹ軸方向の位置は、計算により求めているが、あらかじめＩの値に対応したＸ軸方向およびＹ軸方向の位置もしくは移動量を、テーブルとして用意しておき、かかるテーブルに基づいて前記ステップＳ９２２で投影領域１１０を移動させてもよい。
【０３４６】
［処理Ｓ３０Ｄ］第４の処理は、ステップＳ３１１、Ｓ３１２とで構成される。
【０３４７】
この第４の処理を実行することにより、撮像領域６１１の中心１２５ａと撮像領域６３１の中心１２５ｃとを結ぶ直線１２６（目的線）と、辺１１３とを平行にすることができる。すなわち、辺１１３の傾きを解消することができる。
【０３４８】
［ステップＳ３１１］まず、前記パターンＡ導入処理（処理Ｓ９０ｂ）における前記ステップＳ９２１で最後に求めたエッジ１１２ｃの座標（位置）と、前記ステップＳ３０９の最後のパターンマッチングで得られたエッジ１１２ａの座標とに基づいて、図２３（Ａ７）に示すような、直線１２６と辺１１３ａとの傾きθ１を求める。
【０３４９】
なお、前記パターンＡ導入処理（処理Ｓ９０ｂ）を一度も行わなかった場合には、前記ステップＳ３０７のパターンマッチングで得られた位置１２３が、エッジ１１２ｃの位置となる。
【０３５０】
［ステップＳ３１２］次に、前記ステップＳ３１１で求めたθ１に基づいて、投影領域１１０を回転させる。
【０３５１】
これにより、図２３（Ｂ７１）に示すように、直線１２６と辺１１３ａとを平行にすることができる。
【０３５２】
［処理Ｓ３０Ｅ］第５の処理は、ステップＳ３１３〜Ｓ３１７とで構成される。
【０３５３】
この第５の処理を実行することにより、エッジ１１２ａと１１２ｃとが、目的位置に近づく。また、撮像領域６１１内に入る投影領域１１０の画素数と、撮像領域６３１内に入る投影領域１１０の画素数とをほぼ一致させることができる。
【０３５４】
［ステップＳ３１３］まず、カメラＮｏ．３（カメラ６３）で撮像し、撮像領域６３１の画像データをメモリー４に記憶する。
【０３５５】
［ステップＳ３１４］次に、前記ステップＳ３１３でメモリー４に記憶した画像データに対して、パターンＣ１を検索パターンとして、パターンマッチングを行う。
【０３５６】
［ステップＳ３１５］次に、カメラＮｏ．１（カメラ６１）で撮像し、撮像領域６１１の画像データをメモリー４に記憶する。
【０３５７】
［ステップＳ３１６］次に、前記ステップＳ３１５でメモリー４に記憶した画像データに対して、パターンＡ１を検索パターンとして、パターンマッチングを行う。
【０３５８】
［ステップＳ３１７］次に、前記ステップＳ３１４およびＳ３１６におけるパターンマッチングで得られたエッジ１１２ａとエッジ１１２ｃの位置に基づいて、直線１２６と辺１１３ａとが合致するように、かつ、ｙ１＝ｙ２となるように、投影領域１１０を移動させる。
【０３５９】
なお、ｙ１とは、図２３（Ｂ７２）に示すように、撮像領域６１１の図２３中上の辺６１２と、投影領域１１０の図２３中上の辺１１４ｂとの間の幅である。また、ｙ２とは、撮像領域６３１の図２３中下の辺６３２と、投影領域１１０の図２３中下の辺１１４ａとの間の幅である。
【０３６０】
これにより、図２３（Ｂ７２）に示すように、エッジ１１２ａと１１２ｃとが、目的位置に近づく。また、撮像領域６１１内に入る投影領域１１０の画素数と、撮像領域６３１内に入る投影領域１１０の画素数とがほぼ一致する。
【０３６１】
以下に説明する第６〜第８の処理は、前記第３〜第５の処理と類似の処理である。
【０３６２】
前記第３〜第５の処理は、撮像領域６１１と撮像領域６３１とを基準として位置合わせを行った。すなわち、投影領域１１０のＹ軸方向（辺１１３ａ）、換言すれば、液晶ライトバルブ２５のＹ軸方向に重きを置いた位置合わせを行った。それに対し、以下の第６〜第８の処理では、撮像領域６３１と撮像領域６４１とを基準として位置合わせを行う。すなわち、投影領域１１０のＸ軸方向（辺１１４ａ）、換言すれば、液晶ライトバルブ２５のＸ軸方向に重きを置いた位置合わせを行う。
【０３６３】
［処理Ｓ３０Ｆ］第６の処理は、ステップＳ３１８〜Ｓ３２２とパターンＤ導入処理（処理Ｓ９０ｃ）とで構成される。
【０３６４】
上記第３〜第５の処理を実行することにより、投影領域１１０の角部１１１ａを撮像領域６１１内に導入でき、さらには辺１１３ａを直線１２６と平行にすることができ、さらにはエッジ１１２ａと１１２ｃとを、目的位置に近づけることができた。
【０３６５】
しかし、かかる処理を行った後でも、図２３（Ａ８）に示すように、角部１１１ｄが撮像領域６４１内に入っていない可能性も、非常に少ないが、有り得る。
【０３６６】
このような場合でも、この第６の処理を実行することにより、角部１１１ｄを撮像領域６４１内に導入することができる。
【０３６７】
なお、以下のステップＳ３２０を実行するに先だって、後述するステップＳ９３１で投影領域１１０の移動量を算出するために必要な変数Ｉに、あらかじめ０を代入しておく。
【０３６８】
［ステップＳ３１８］まず、カメラＮｏ．３（カメラ６３）で撮像し、撮像領域６３１の画像データをメモリー４に記憶する。
【０３６９】
［ステップＳ３１９］次に、前記ステップＳ３１８でメモリー４に記憶した画像データに対して、パターンＣ１を検索パターンとして、パターンマッチングを行う。
【０３７０】
［ステップＳ３２０］次に、カメラＮｏ．４（カメラ６４）で撮像し、撮像領域６４１の画像データをメモリー４に記憶する。
【０３７１】
［ステップＳ３２１］次に、前記ステップＳ３２０でメモリー４に記憶した画像データに対して、パターンＤ１を検索パターンとして、パターンマッチングを行う。
【０３７２】
［ステップＳ３２２］次に、パターンマッチングを行った結果、前記ステップＳ３２０でメモリー４に記憶した画像データにパターンＤ１が存在しない場合、すなわち図２３（Ａ８）に示すように、撮像領域６４１内に角部１１１ｄが存在しない場合には、パターンＤ導入処理（処理Ｓ９０ｃ）を実行する。一方、パターンＤ１が存在する場合には、第７の処理（処理Ｓ３０Ｇ）すなわちステップＳ３２３を実行する。
【０３７３】
［処理Ｓ９０ｃ］パターンＤ導入処理は、ステップＳ９３１、Ｓ９３２とで構成される。
【０３７４】
このパターンＤ導入処理を所定回数実行することにより、角部１１１ｄを撮像領域６４１内に導入することができる。
【０３７５】
［ステップＳ９３１］まず、次のステップＳ９３２で投影領域１１０を移動させる際の移動先のエッジ１１２ｃの位置（座標）を求める。これは、例えば次の式で求めることができる。この式は、Ｉの値に対応したエッジ１１２ｃの座標を与える。なお、前述したように、ｎは、撮像領域６３１のＹ軸方向の長さであり、ｍは、撮像領域６３１のＸ軸方向の長さである。
【０３７６】
Ｘ軸方向の位置 ＝ ＩＤＯＵ＿Ｘ２ ＋ （Ｉ ｍｏｄ ３）＊（ｍ）
（ここで、（Ｉ ｍｏｄ ３）とは、Ｉを３で割ったときの余りを求めることを意味する）
Ｙ軸方向の位置 ＝ ＩＤＯＵ＿Ｙ２ ＋ （Ｉ／３）＊（ｎ／３） （なお、得られた移動量の小数点以下は切り捨てる）
ここで、定数ＩＤＯＵ＿Ｘ２およびＩＤＯＵ＿Ｙ２は、Ｉ＝０のときの、次のステップＳ９３２におけるエッジ１１２ｃの移動先の座標に対応している。
【０３７７】
これら定数ＩＤＯＵ＿Ｘ２およびＩＤＯＵ＿Ｙ２としては、Ｉ＝０のときの移動後のエッジ１１２ｃの位置が、投影領域６３１の中心１２５ｃよりも図２３中左上に来るような値が好ましい。これにより、エッジ１１２ｄを効率よく撮像領域６４１内に導入することができる。
【０３７８】
［ステップＳ９３２］次に、前記ステップＳ９３１で求めたエッジ１１２ｃの移動先の位置に、エッジ１１２ｃが来るように、投影領域１１０を移動させる。なお、Ｙ軸方向に移動させる処理は、省略することもできる（Ｘ軸方向のみに移動させてもよい）。
【０３７９】
これにより、Ｉが所定の値になった場合に、エッジ１１２ｄが、撮像領域６４１内に入る。
【０３８０】
その後、ステップＳ３２０へ戻る。そのとき、Ｉに１を加える。
【０３８１】
このように、Ｉの値を変化させつつパターンＤ導入処理（処理Ｓ９０ｃ）を所定回数実行することにより、エッジ１１２ｄを撮像領域６４１内に入れることができる。
【０３８２】
なお、前記ステップＳ９３１において、エッジ１１２ｃのＸ軸方向の位置およびＹ軸方向の位置は、同一の変数Ｉによりそれぞれを求めているが、Ｘ軸およびＹ軸に対応した変数をそれぞれ用意し、Ｘ軸方向の位置およびＹ軸方向の位置を、これら用意した変数からそれぞれ独立に求めてもよい。
【０３８３】
なお、前記ステップＳ９３１において、エッジ１１２ｃのＸ軸方向の位置およびＹ軸方向の位置は、計算により求めているが、あらかじめＩの値に対応したＸ軸方向およびＹ軸方向の位置もしくは移動量を、テーブルとして用意しておき、かかるテーブルに基づいて前記ステップ９３２で投影領域１１０を移動させてもよい。
【０３８４】
［処理Ｓ３０Ｇ］第７の処理は、ステップＳ３２３、Ｓ３２４とで構成される。
【０３８５】
この第７の処理を実行することにより、撮像領域６３１の中心１２５ｃと撮像領域６４１の中心１２５ｄとを結ぶ直線１２７（目的線）と、辺１１４ａとを平行にすることができる。すなわち、辺１１４ａの傾きを解消することができる。
【０３８６】
［ステップＳ３２３］まず、前記パターンＤ導入処理（処理Ｓ９０ｃ）における前記ステップＳ９３１で最後に求めたエッジ１１２ｃの座標（位置）と、前記ステップＳ３２１の最後のパターンマッチングで得られたエッジ１１２ｄの座標とに基づいて、図２４（Ａ９）に示すような、直線１２７と辺１１４ａとの傾きθ２を求める。
【０３８７】
なお、前記パターンＤ導入処理（処理Ｓ９０ｃ）を一度も行わなかった場合には、前記ステップＳ３１９のパターンマッチングで得られた位置１２３が、エッジ１１２ｃの位置となる。
【０３８８】
［ステップＳ３２４］次に、前記ステップＳ３２３で求めたθ２に基づいて、投影領域１１０を回転させる。
【０３８９】
これにより、図２４（Ｂ９１）に示すように、直線１２７と辺１１４ａとを平行にすることができる。
【０３９０】
［処理Ｓ３０Ｈ］第８の処理は、ステップＳ３２５〜Ｓ３２９とで構成される。
【０３９１】
この第８の処理を実行することにより、エッジ１１２ｃと１１２ｄとが、目的位置に近づく。また、撮像領域６３１内に入る投影領域１１０の画素数と、撮像領域６４１内に入る投影領域１１０の画素数とをほぼ一致させることができる。
【０３９２】
［ステップＳ３２５］まず、カメラＮｏ．３（カメラ６３）で撮像し、撮像領域６３１の画像データをメモリー４に記憶する。
【０３９３】
［ステップＳ３２６］次に、前記ステップＳ３２５でメモリー４に記憶した画像データに対して、パターンＣ１を検索パターンとして、パターンマッチングを行う。
【０３９４】
［ステップＳ３２７］次に、カメラＮｏ．４（カメラ６４）で撮像し、撮像領域６４１の画像データをメモリー４に記憶する。
【０３９５】
［ステップＳ３２８］次に、前記ステップＳ３２７でメモリー４に記憶した画像データに対して、パターンＤ１を検索パターンとして、パターンマッチングを行う。
【０３９６】
［ステップＳ３２９］次に、前記ステップＳ３１４およびＳ３１６におけるパターンマッチングで得られたエッジ１１２ｃとエッジ１１２ｄの位置に基づいて、直線１２７と辺１１４ａとが合致するように、かつ、ｘ１＝ｘ２となるように、投影領域１１０を移動させる。
【０３９７】
なお、ｘ１とは、図２４（Ｂ９２）に示すように、撮像領域６３１の図２４中左の辺６３３と、投影領域１１０の図２４中左の辺１１３ａとの間の幅である。また、ｘ２とは、撮像領域６４１の図２４中右の辺６４３と、投影領域１１０の図２４中右の辺１１３ｂとの間の幅である。
【０３９８】
これにより、図２４（Ｂ９２）に示すように、エッジ１１２ｃと１１２ｄとが、目的位置に近づく。また、撮像領域６３１内に入る投影領域１１０の画素数と、撮像領域６４１内に入る投影領域１１０の画素数とがほぼ一致する。
【０３９９】
以上で、粗調整が終了する。
【０４００】
以下、ステップＳ３５０の微調整（位置調整処理）の第１の実施の形態について説明する。
【０４０１】
以下のステップＳ３５０の微調整を行うことにより、アライメントを非常に高精度で調整することができる。さらには、図２５（Ａ１３）に示すような、投影領域１１０が、完全に長方形でない場合でも、正確にアライメント調整を行うことができる。
【０４０２】
ステップＳ３５０の微調整を説明するに先立って、ステップＳ３５０の微調整中で適宜行われる四頂点位置計測処理（処理Ｓ９０ｄ）についてまず説明する。
【０４０３】
［処理Ｓ９０ｄ］図１８に示すように、四頂点位置計測処理は、ステップＳ９４１〜Ｓ９４８で構成される。
【０４０４】
この四頂点位置計測処理を実行することにより、エッジ１１２ａ、エッジ１１２ｂ、エッジ１１２ｃおよびエッジ１１２ｄの座標を得ることができる。
【０４０５】
［ステップＳ９４１］まず、カメラＮｏ．１（カメラ６１）で撮像し、撮像領域６１１の画像データをメモリー４に記憶する。
【０４０６】
［ステップＳ９４２］次に、前記ステップＳ９４１でメモリー４に記憶した画像データに対して、パターンＡ１を検索パターンとして、パターンマッチングを行う。
【０４０７】
［ステップＳ９４３］次に、カメラＮｏ．２（カメラ６２）で撮像し、撮像領域６２１の画像データをメモリー４に記憶する。
【０４０８】
［ステップＳ９４４］次に、前記ステップＳ９４３でメモリー４に記憶した画像データに対して、パターンＢ１を検索パターンとして、パターンマッチングを行う。
【０４０９】
［ステップＳ９４５］次に、カメラＮｏ．３（カメラ６３）で撮像し、撮像領域６３１の画像データをメモリー４に記憶する。
【０４１０】
［ステップＳ９４６］次に、前記ステップＳ９４５でメモリー４に記憶した画像データに対して、パターンＣ１を検索パターンとして、パターンマッチングを行う。
【０４１１】
［ステップＳ９４７］次に、カメラＮｏ．４（カメラ６４）で撮像し、撮像領域６４１の画像データをメモリー４に記憶する。
【０４１２】
［ステップＳ９４８］次に、前記ステップＳ９４７でメモリー４に記憶した画像データに対して、パターンＤ１を検索パターンとして、パターンマッチングを行う。
【０４１３】
なお、以上の四頂点位置計測処理（処理Ｓ９０ｄ）で得られたエッジ１１２ａの座標を（ｇｌｕｘｇ，ｇｌｕｙｇ）、エッジ１１２ｂの座標を（ｇｒｕｘｇ，ｇｒｕｙｇ）、エッジ１１２ｃの座標を（ｇｌｄｘｇ，ｇｌｄｙｇ）、エッジ１１２ｄの座標を（ｇｒｄｘｇ，ｇｒｄｙｇ）とする（図２５（Ａ１０）参照）。
【０４１４】
ステップＳ３５０の微調整では、第１の処理（処理Ｓ３５Ａ）と、第２の処理（処理Ｓ３５Ｂ）と、第３の処理（処理Ｓ３５Ｃ）とを行う。以下、図１７、１８、２５に基づいて、各処理を、ステップごとに詳細に説明する。
【０４１５】
［処理Ｓ３５Ａ］第１の処理は、四頂点位置計測処理（処理Ｓ９０ｄ）と、ステップＳ３５１〜Ｓ３５３とで構成される。
【０４１６】
この第１の処理を実行することにより、投影領域１１０全体の傾き、すなわち、液晶ライトバルブ２５全体の傾きが最も小さくなる。
【０４１７】
［処理Ｓ９０ｄ］まず、前述した四頂点位置計測処理を実行する。
【０４１８】
［ステップＳ３５１］次に、この四頂点位置計測処理により得られたエッジ１１２ａ〜１１２ｄの座標に基づいて、θｇｕｘ、θｇｄｘ、θｇｌｙおよびθｇｒｙを求める。
【０４１９】
図２５（Ａ１１）に示すように、θｇｕｘは、辺１１４ｂと、撮像領域６１１の中心１２５ａと撮像領域６２１の中心１２５ｂとを結ぶ線との間の角度である。θｇｄｘは、辺１１４ａと、撮像領域６３１の中心１２５ｃと撮像領域６４１の中心１２５ｄとを結ぶ線との間の角度である。θｇｌｙは、辺１１３ａと、撮像領域６１１の中心１２５ａと撮像領域６３１の中心１２５ｃとを結ぶ線との間の角度である。θｇｒｙは、辺１１３ｂと、撮像領域６２１の中心１２５ｂと撮像領域６４１の中心１２５ｄとを結ぶ線との間の角度である。
【０４２０】
これらθｇｕｘ、θｇｄｘ、θｇｌｙおよびθｇｒｙは、四頂点位置計測処理（処理Ｓ９０ｄ）で得られたエッジ１１２ａ〜１１２ｄの座標（ｇｌｕｘｇ，ｇｌｕｙｇ）、（ｇｒｕｘｇ，ｇｒｕｙｇ）、（ｇｌｄｘｇ，ｇｌｄｙｇ）および（ｇｒｄｘｇ，ｇｒｄｙｇ）と、中心１２５ａ〜ｄの座標とから求めることができる。
【０４２１】
［ステップＳ３５２］次に、前記ステップＳ３５１で求めたθｇｕｘ、θｇｄｘ、θｇｌｙおよびθｇｒｙに基づいて、次のステップＳ３５３で投影領域１１０を回転させる際の回転角度θを求める。
【０４２２】
これは、次の式から求めることができる。なお、θｋとは、あらかじめ設定された基準角度である。
【０４２３】
θｇｘ ＝ （θｇｕｘ ＋ θｇｄｘ）／２
θｇｙ ＝ （θｇｌｙ ＋ θｇｒｙ）／２
θｇ ＝ （θｇｘ ＋ θｇｙ）／２
θ ＝ θｋ − θｇ
［ステップＳ３５３］次に、投影領域１１０を、前記ステップＳ３５２で求めた回転角度θ度回転させる。
【０４２４】
これにより、図２５（Ｂ１２）に示すように、投影領域１１０のＸ軸方向およびｙ軸方向の傾きが最も小さくなる。
【０４２５】
［処理Ｓ３５Ｂ］第２の処理は、四頂点位置計測処理（処理Ｓ９０ｄ）と、ステップＳ３５４〜Ｓ３５６とで構成される。
【０４２６】
この第２の処理を実行することにより、投影領域１１０の中心の位置が、あらかじめ設定された基準座標に合致する。すなわち、この第２の処理を実行することにより、投影領域１１０の中心の位置を調整することができる。
【０４２７】
［処理Ｓ９０ｄ］まず、前述した四頂点位置計測処理を実行する。
【０４２８】
［ステップＳ３５４］次に、この四頂点位置計測処理により得られたエッジ１１２ａ〜１１２ｄの座標に基づいて、投影領域１１０の中心座標（ｇｘｇ，ｇｙｇ）を求める。
【０４２９】
この座標は、例えば、四頂点位置計測処理（処理Ｓ９０ｄ）で得られたエッジ１１２ａ〜１１２ｄの座標（ｇｌｕｘｇ，ｇｌｕｙｇ）、（ｇｒｕｘｇ，ｇｒｕｙｇ）、（ｇｌｄｘｇ，ｇｌｄｙｇ）、（ｇｒｄｘｇ，ｇｒｄｙｇ）から、辺１１３ａ、１１３ｂ、１１４ａおよび１１４ｂの中点の座標をそれぞれ求め、これらの中点の座標から、辺１１３ａの中点と辺１１３ｂの中点とを結ぶ直線と、辺１１４ａの中点と辺１１４ｂの中点とを結ぶ直線との交点の座標を求めることにより得ることができる。
【０４３０】
すなわち、辺１１３ａの中点と辺１１３ｂの中点とを結ぶ直線と、辺１１４ａの中点と辺１１４ｂの中点とを結ぶ直線との交点の座標が、投影領域１１０の中心座標（ｇｘｇ，ｇｙｇ）となる。
【０４３１】
［ステップＳ３５５］次に、前記ステップＳ３５４で求めた投影領域１１０の中心座標（ｇｘｇ，ｇｙｇ）に基づいて、次のステップＳ３５６で投影領域１１０を移動させる際の移動量を求める。
【０４３２】
これは、次の式から求めることができる。なお、ｋｘｇとｋｙｇは、あらかじめ設定された基準座標である。
【０４３３】
Ｘ軸移動量 ＝ ｋｘｇ − ｇｘｇ
Ｙ軸移動量 ＝ ｋｙｇ − ｇｙｇ
［ステップＳ３５６］次に、投影領域１１０を、前記ステップＳ３５５で求めたＸ軸移動量およびＹ軸移動量に基づいて移動させる。
【０４３４】
これにより、撮像領域１１０の中心が基準座標に移動する。
【０４３５】
［処理Ｓ３５Ｃ］第３の処理は、四頂点位置計測処理（処理Ｓ９０ｄ）と、ステップＳ３５７〜Ｓ３５９とで構成される。
【０４３６】
この第３の処理を実行することにより、液晶ライトバルブ２５全体を、Ｘ軸方向およびＹ軸方向のずれが最も小さくなる位置に調整することができる。
【０４３７】
［処理Ｓ９０ｄ］まず、前述した四頂点位置計測処理を実行する。
【０４３８】
［ステップＳ３５７］次に、この四頂点位置計測処理により得られたエッジ１１２ａ〜１１２ｄの座標について、エッジ１１２ａ〜１１２ｄごとにそれぞれあらかじめ設定された基準座標（目的位置）からのずれを求める。
【０４３９】
ここで、エッジ１１２ａの基準座標を（ｋｌｕｘｇ，ｋｌｕｙｇ）、エッジ１１２ｂの基準座標を（ｋｒｕｘｇ，ｋｒｕｙｇ）、エッジ１１２ｃの基準座標を（ｋｌｄｘｇ，ｋｌｄｙｇ）、エッジ１１２ｄの基準座標を（ｋｒｄｘｇ，ｋｒｄｙｇ）とする。
【０４４０】
ここで、エッジ１１２ａ〜１１２ｄのＸ軸方向の基準座標からのずれをそれぞれＸ１〜Ｘ４、エッジ１１２ａ〜１１２ｄのＹ軸方向の基準座標からのずれをそれぞれＹ１〜Ｙ４とすると、Ｘ１〜Ｘ４およびＹ１〜Ｙ４は、例えば次の式で表すことができる。
【０４４１】
Ｘ１ ＝ ｋｌｕｘｇ − ｇｌｕｘｇ
Ｘ２ ＝ ｇｒｕｘｇ − ｋｒｕｘｇ
Ｘ３ ＝ ｋｌｄｘｇ − ｇｌｄｘｇ
Ｘ４ ＝ ｇｒｄｘｇ − ｋｒｄｘｇ
Ｙ１ ＝ ｋｌｕｙｇ − ｇｌｕｙｇ
Ｙ２ ＝ ｋｒｕｙｇ − ｇｒｕｙｇ
Ｙ３ ＝ ｇｌｄｙｇ − ｋｌｄｙｇ
Ｙ４ ＝ ｇｒｄｙｇ − ｋｒｄｙｇ
［ステップＳ３５８］次に、前記ステップＳ３５７で求めたＸ１〜Ｘ４およびＹ１〜Ｙ４に基づいて、次のステップＳ３５９で投影領域１１０を移動させる際の移動量を求める。
【０４４２】
Ｘ軸方向の移動量は、Ｘ１〜Ｘ４のうち、１番目に大きい絶対値と２番目に大きい絶対値を有するものの平均をとることにより求める。なお、絶対値が１番大きいものと２番目に大きいものの値の正負が同符号の場合は、Ｘ１〜Ｘ４のうち、１番目に大きい絶対値と３番目に大きい絶対値を有するものの平均をとることにより、Ｘ軸方向の移動量を求める。さらには、絶対値が１番大きいものと３番目に大きいものの値の正負が同符号の場合は、Ｘ１〜Ｘ４のうち、１番目に大きい絶対値と４番目に大きい絶対値を有するものの平均をとることにより、Ｘ軸方向の移動量を求める。
【０４４３】
Ｙ軸方向の移動量は、Ｙ１〜Ｙ４のうち、１番目に大きい絶対値と２番目に大きい絶対値を有するものの平均をとることにより求める。なお、絶対値が１番大きいものと２番目に大きいものの値の正負が同符号の場合は、Ｙ１〜Ｙ４のうち、１番目に大きい絶対値と３番目に大きい絶対値を有するものの平均をとることにより、Ｙ軸方向の移動量を求める。さらには、絶対値が１番大きいものと３番目に大きいものの値の正負が同符号の場合は、Ｙ１〜Ｙ４のうち、１番目に大きい絶対値と４番目に大きい絶対値を有するものの平均をとることにより、Ｙ軸方向の移動量を求める。
【０４４４】
［ステップＳ３５９］次に、前記ステップＳ３５８で求めたＸ軸方向の移動量およびＹ軸方向の移動量に基づいて、投影領域１１０を移動させる。
【０４４５】
これによりエッジ１１２ａ〜１１２ｄ（角部１１１ａ〜１１１ｄ）のうち、これらに対応する基準座標から最も離れたエッジ（角部）は、かかる基準座標に近づく。
【０４４６】
従って、例えば、図２５（Ａ１３）に示すように、投影領域１１０が、完全に長方形でない場合でも、正確に位置調整を行うことができる。
【０４４７】
以上で、第１の実施の形態のステップＳ３５０の微調整（位置調整処理）が終了する。
【０４４８】
なお、この微調整では、第１の処理（処理Ｓ３５Ａ）、第２の処理（処理Ｓ３５Ｂ）および第３の処理（処理Ｓ３５Ｃ）の各処理ごとに四頂点位置計測処理（処理Ｓ９０ｄ）を行っているが、各処理ごとに四頂点位置計測処理（処理Ｓ９０ｄ）を行わなくてもよい。ただし、この第１の実施の形態のように、各処理ごとに四頂点位置計測処理（処理Ｓ９０ｄ）を実行することが好ましい。これにより、アライメント調整の精度がより向上する。
【０４４９】
なお、この微調整では、四頂点位置計測処理（処理Ｓ９０ｄ）を行い、エッジ１１２ａ〜１１２ｄの座標をそれぞれ求め、第１〜第３の処理（処理Ｓ３５Ａ〜処理Ｓ３５Ｃ）を行っているが、エッジ１１２ａ〜１１２ｄの座標のうちの少なくとも２つの座標を求め、かかる座標に基づいて、第１の処理（処理Ｓ３５Ａ）、第２の処理（処理Ｓ３５Ｂ）および第３の処理（処理Ｓ３５Ｃ）を行ってもよい。
【０４５０】
アライメント調整において、光学系の特性（レンズの収差）等により、スクリーン２上に投影される画像（投影画像）、すなわちライトバルブの画素の投影画像が変形する（例えば、カブリ、ムラ、ぼけ、にじみ等が生じる）ことがある。
【０４５１】
このような場合、例えば、図１１に示すようなパターンＡ１〜Ｄ１を検索パターンとしてパターンマッチングを行った場合、検索を的確に行うことが困難な場合がある。
【０４５２】
このときは、図２６に示すような、パターンＡ２、Ｂ２、Ｃ２およびＤ２を検索パターンとして、パターンマッチングを行ってもよい。これら各パターンＡ２、Ｂ２、Ｃ２およびＤ２は、それぞれ、液晶ライトバルブの画素の投影像にレンズの収差による投影画像の変形がある場合に、対応する角部１１１ａ、１１１ｂ、１１１ｃおよび１１１ｄを含む部分に対応するものである。
【０４５３】
さらには、まずは、図１１に示すようなパターンＡ１〜Ｄ１を検索パターンとしてパターンマッチングを行い、かかるパターンマッチングで、被検索データ中に検索パターンが存在しなかった場合に、図２６に示すようなパターンＡ２〜Ｄ２を検索パターンとして再びパターンマッチングを行うようにしてもよい。
【０４５４】
このように、パターンマッチングに用いる所定のパターン（１つの角部に対応するパターン）を複数設定しておくことにより、レンズの収差による投影画像の変形の程度が異なる場合に、容易に対応することができ、アライメントの精度を向上させることができる。
【０４５５】
この場合、図２６に示すように、パターンＡ２〜Ｄ２中において、位置１２１、１２２、１２３および１２４は、例えば、各画素にレンズの収差による投影画像の変形がないときのエッジ１１２ａ、１１２ｂ、１１２ｃおよび１１２ｄの位置に対応したものとすることができる。
【０４５６】
また前記と同様に、図１２に示すようなパターンＨ１およびパターンＶ１についても、図２７に示すような、パターンＨ１およびパターンＶ１に対応したパターンＨ２およびパターンＶ２を用意して、これらを用いてパターンマッチングを行うことができる。
【０４５７】
これらパターンＨ２およびパターンＶ２は、それぞれ、液晶ライトバルブの画素の投影像にレンズの収差による投影画像の変形がある場合に、対応する辺１１３ａおよび１１４ａを含む部分に対応したものである。
【０４５８】
この場合、図２７に示すように、パターンＨ２およびＶ２中において、位置１２９ａおよび１２９ｂは、例えば、各画素にレンズの収差による投影画像の変形がないとしたときの辺１１３ａおよび１１４ａ上に重なるような位置とすることができる。
【０４５９】
以下、ステップＳ３５０の微調整（位置調整処理）の第２の実施の形態について説明する。
【０４６０】
微調整では、まず、カメラＮｏ．１、カメラＮｏ．２、カメラＮｏ．３およびカメラＮｏ．４でそれぞれ撮像し、撮像領域６１１、６２１、６３１および６４１の各画像データをメモリー４に記憶する。
【０４６１】
次いで、メモリー４からカメラＮｏ．１、カメラＮｏ．２、カメラＮｏ．３およびカメラＮｏ．４で撮像された画像の各画像データをそれぞれ読み出し、エッジ処理（エッジ処理法）により、図２８（ａ）に示す各特定位置１２８を検出する（特定位置１２８のＸ座標およびＹ座標を求める）。なお、このエッジ処理については後に詳述する。
【０４６２】
そして、図２８（ｂ）に示すように、各特定位置１２８がそれぞれ対応する目的位置にさらに近づくように（一致する場合も含む）、３軸テーブル９により、液晶ライトバルブ２５を変位させる。すなわち、各特定位置１２８がそれぞれ対応する目的位置にさらに近づくように（一致する場合も含む）、液晶ライトバルブ２５をＷ方向に回転させ、Ｘ軸方向およびＹ軸方向に移動させる。
【０４６３】
次に、エッジ処理について説明する。なお、代表的に、カメラＮｏ．４で撮像した画像の特定位置のＹ座標を求める場合を説明する。
【０４６４】
図２９は、エッジ処理における位置決め装置１の制御手段３の制御動作を示すフローチャートである。以下、このフローチャートに基づいて説明する。
【０４６５】
エッジ処理では、まず、カメラＮｏ．４（本実施例では、画素：４００行×６００列）で撮像し、撮像領域６４１の画像データをメモリー４に記憶する（ステップＳ４０１）。
【０４６６】
前記カメラＮｏ．４で撮像された画像、すなわち、メモリー４に記憶された画像は、例えば、図３０に示す通りである。
【０４６７】
図３０に示すように、Ｘ−Ｙ座標を想定する。このＸ−Ｙ座標は、電子画像の面に対応している。すなわち、カメラＮｏ．４の各画素の列（第１列〜第６００列）および行（第１行〜第４００行）は、それぞれ、その画素のＸ軸方向の座標（Ｘ座標）およびＹ軸方向の座標（Ｙ座標）に対応する。本実施例では、カメラＮｏ．４の第ｊ行（ｊ行目）、第ｉ列（ｉ列目）の画素の座標は、（ｉ，ｊ）である。
【０４６８】
次いで、各画素における輝度をＹ軸方向に積算し、Ｙ軸方向の輝度の積算値Ｉy[i]＝Σ f（i,j ）を求める（ステップＳ４０２）。
【０４６９】
前記積算値Ｉy[i]のグラフを図３０に示す。なお、グラフの縦軸に、積算値Ｉy[i]、横軸に、画素のＸ座標ｉをとる。
【０４７０】
次いで、前記積算値Ｉy[i]の最大値Ｉymaxと、最小値Ｉyminとをそれぞれ求める（ステップＳ４０３）。
【０４７１】
次いで、しきい値Ｔy を設定する（ステップＳ４０４）。
【０４７２】
このステップＳ４０４では、前記ステップＳ４０３で求めた最大値Ｉymaxおよび最小値Ｉyminを下記式に代入することにより、しきい値Ｔy を求める。
【０４７３】
Ｔy ＝（Ｉymax−Ｉymin）＊α＋Ｉymin（但し、０＜α＜１）
次いで、図３０に示すように、しきい値Ｔy と積算値Ｉy[i]とのクロス点のＸ座標Ｘc を求める（ステップＳ４０５）。
【０４７４】
次いで、図３１に示すように、座標（０，０）、座標（Ｘc ，０）、座標（Ｘc ，４００）および座標（０，４００）の４点で囲まれる四角形の領域を設定する（ステップＳ４０６）。
【０４７５】
次いで、前記設定された領域内において、各画素における輝度をＸ軸方向に積算し、Ｘ軸方向の輝度の積算値Ｉax[j] ＝Σ f（i,j ）を求める（ステップＳ４０７）。
【０４７６】
前記積算値Ｉax[j] （第１の波形）のグラフを図３１に示す。なお、グラフの横軸に、積算値Ｉax[j] 、縦軸に、画素のＹ座標ｊをとる。この積算値Ｉax[j] をＸ軸方向の輝度の積算値のＹ軸方向における変化を示す第１の波形とする。
【０４７７】
次いで、前記積算値Ｉax[j] の最大値Ｉaxmax と、最小値Ｉaxmin とをそれぞれ求める（ステップＳ４０８）。
【０４７８】
次いで、しきい値Ｔaxを設定する（ステップＳ４０９）。
【０４７９】
このステップＳ４０９では、前記ステップＳ４０８で求めた最大値Ｉaxmax および最小値Ｉaxmin を下記式に代入することにより、しきい値Ｔaxを求める。
【０４８０】
Ｔax＝（Ｉaxmax −Ｉaxmin ）＊α＋Ｉaxmin （但し、０＜α＜１）
次いで、図３１に示すように、しきい値Ｔaxと積算値Ｉax[j] とのクロス点のＹ座標Ｙacを求める（ステップＳ４１０）。
【０４８１】
次いで、図３１に示すように、積算値Ｉax[j] のグラフの各ピーク（正ピーク）におけるＹ座標Ｐpy[P] と、各ボトム（負ピーク）におけるＹ座標Ｐmy[q] とをそれぞれ求める（ステップＳ４１１）。
【０４８２】
なお、図３１の場合には、正ピークの数が４、負ピークの数が３であるので、前記４つの正ピークにおけるＹ座標Ｐpy[1] 、Ｐpy[2] 、Ｐpy[3] およびＰpy[4] と、前記３つの負ピークにおけるＹ座標Ｐmy[1] 、Ｐmy[2] およびＰmy[3] とがそれぞれ検出される。
【０４８３】
次いで、下記式から、隣接する正ピークの縦軸方向の間隔の平均値Ｐpyavr を求める（ステップＳ４１２）。
【０４８４】
Ｐpyavr ＝｛Σ（Ｐpy[p＋１] −Ｐpy[p] ）｝／（ｎ−１）
（但し、ｎは、正ピークの数である）
次いで、図３１に示すように、Ｙ座標がＹac−１．２＊Ｐpyavr 未満の範囲で、Ｙac−１．２＊Ｐpyavr −Ｐmy[q] が最小となる負のピークにおけるＹ座標Ｐmpymaxを検出する（ステップＳ４１３）。
【０４８５】
なお、換言すれば、前記Ｐmpymaxは、Ｙac−１．２＊Ｐpyavr より小さく、かつ、Ｙac−１．２＊Ｐpyavr に最も近いＰmy[q] である。
【０４８６】
次いで、下記式から、積算値Ｉax[j] の差分値Ｄiax[j]を計算する（ステップＳ４１４）。
【０４８７】
Ｄiax[j]＝Ｉax[j＋１] −Ｉax[j−１］
なお、換言すれば、ｊ行目の差分値Ｄiax[j]は、ｊ＋１行目の積算値Ｉax[j＋１] からｊ−１行目の積算値Ｉax[j−１］を引いた値である。
【０４８８】
前記差分値Ｄiax[j]のグラフと、積算値Ｉax[j] のグラフとを図３２に示す。なお、差分値Ｄiax[j]のグラフでは、その横軸に、差分値Ｄiax[j]、縦軸に、画素のＹ座標ｊをとる。
【０４８９】
次いで、図３２に示すように、Ｐmpymax付近（図３２中丸で示す）で、Ｄiax[j]を用いてゼロクロス点（Ｄiax[j]＝０のときのＹ座標）を計算し（ゼロクロス処理を行い）、得られたゼロクロス点を特定位置のＹ座標とする（ステップＳ４１５）。
【０４９０】
すなわち、このステップＳ４１５により、カメラＮｏ．４で撮像した画像の特定位置のＹ座標が求まる。
【０４９１】
以上で、エッジ処理を終了する。
【０４９２】
なお、カメラＮｏ．４で撮像された画像の特定位置のＸ座標を求めるには、前述した特定位置のＹ座標を求めるエッジ処理において、ｘをｙに、ｙをｘに変えて同様に行えばよい。
【０４９３】
この場合、設定された領域内において、各画素における輝度をＹ軸方向に積算したＹ軸方向の輝度の積算値と、画素のＸ座標との関係（Ｙ軸方向の輝度の積算値のＸ軸方向における変化）を示す図示しないグラフにおける波形が、第２の波形であり、前述した特定位置のＹ座標を求めるエッジ処理と同様に、この第２の波形に基づいて特定位置のＸ座標を求める。
【０４９４】
図３３は、第１の波形および第２の波形を示す図である。
【０４９５】
同図に示すように、第２の実施の形態では、図３３中下側（撮像された投影領域の端部側）から、第１の波形のピークおよびボトムの４番目のＹ軸方向の位置が特定位置１２８のＹ座標とされ、図３３中右側（撮像された投影領域の端部側）から、第２の波形のピークおよびボトムの４番目のＸ軸方向の位置が特定位置１２８のＸ座標とされる。
【０４９６】
また、カメラＮｏ．１、カメラＮｏ．２およびカメラＮｏ．３で撮像された各画像の特定位置のＸ座標およびＹ座標を求めるには、それぞれ、前述したように行えばよい。
【０４９７】
以上で、第２の実施の形態のステップＳ３５０の微調整（位置調整処理）が終了する。
【０４９８】
以上のようなエッジ処理のフローチャートから判るように、第２の実施の形態のステップＳ３５０の微調整では、エッジ処理において、図３３に示す第１の波形のピークまたはボトムのＹ軸方向の位置を特定位置のＹ座標とし、第２の波形のピークまたはボトムのＸ軸方向の位置を特定位置のＸ座標とするのが好ましい。
【０４９９】
また、図３３中下側（撮像された投影領域の端部側）から、第１の波形のピークおよびボトム（１次微分係数が０となる点）のＮy 番目のＹ軸方向の位置を特定位置のＹ座標とし、図３３中右側（撮像された投影領域の端部側）から、第２の波形のピークおよびボトム（１次微分係数が０となる点）のＮx 番目のＸ軸方向の位置を特定位置のＸ座標とするのが好ましい。
【０５００】
この場合、Ｎy とＮx は、異なっていてもよいが、等しいのが好ましい。Ｎy とＮx とを等しくすることにより、位置調整の精度をより高くすることができる。
【０５０１】
また、Ｎy およびＮx は、それぞれ、偶数であるのが好ましい。すなわち、第１の波形のボトムのＹ軸方向の位置を特定位置のＹ座標とするのが好ましく、また、第２の波形のボトムのＸ軸方向の位置を特定位置のＸ座標とするのが好ましい。
【０５０２】
Ｎy 、Ｎx が偶数であると、より正確に特定位置のＹ座標、Ｘ座標を求めることができ、これにより位置調整の精度を向上させることができる。
【０５０３】
また、Ｎy およびＮx は、それぞれ、２以上であるのが好ましく、４以上であるのがより好ましく、４〜８程度がさらに好ましい。
【０５０４】
Ｎy 、Ｎx が２以上であると、より正確に特定位置のＹ座標、Ｘ座標を求めることができ、これにより位置調整の精度を向上させることができる。
【０５０５】
以上で、緑色用の液晶ライトバルブ２５の位置決めが終了し、前述したように、この液晶ライトバルブ２５は、光学ブロック２０に仮固定され、この後、本固定される。
【０５０６】
次いで、前記と同様に、赤色用の液晶ライトバルブ２４および青色用の液晶ライトバルブ２６の位置決めが行われる。
【０５０７】
このとき、ステップＳ３５０の微調整（位置調整処理）を第１の実施の形態の微調整で行う場合には、次のように行うことにより、緑色用の液晶ライトバルブ２５と、赤色用の液晶ライトバルブ２４と、青色用の液晶ライトバルブ２６とにより形成された各画像が重なるように、赤色用の液晶ライトバルブ２４および青色用の液晶ライトバルブ２６の位置決めを行うことができる。
【０５０８】
まず、赤色用の液晶ライトバルブ２４および青色用の液晶ライトバルブ２６の位置決めを行うに先立って、前記四頂点位置計測処理（処理Ｓ９０ｄ）を行い、緑色用の液晶ライトバルブ２５の投影領域１１０のエッジ１１２ａ〜１１２ｄの座標を得る。
【０５０９】
かかる座標に基づいて、赤色用の液晶ライトバルブ２４および青色用の液晶ライトバルブ２６の位置決めにおいてステップＳ３５２で用いられるθｋと、ステップＳ３５５で用いられるｋｘｇおよびｋｙｇと、ステップＳ３５７で用いられるエッジ１１２ａ〜１１２ｄの基準座標（ｋｌｕｘｇ，ｋｌｕｙｇ）と（ｋｒｕｘｇ，ｋｒｕｙｇ）と（ｋｌｄｘｇ，ｋｌｄｙｇ）と（ｋｒｄｘｇ，ｋｒｄｙｇ）とを求める。
【０５１０】
そして、これらの値に基づいて、赤色用の液晶ライトバルブ２４および青色用の液晶ライトバルブ２６の位置決めを行う。
【０５１１】
これにより、緑色用の液晶ライトバルブ２５と、赤色用の液晶ライトバルブ２４と、青色用の液晶ライトバルブ２６とにより形成された各画像が重なるように、赤色用の液晶ライトバルブ２４および青色用の液晶ライトバルブ２６の位置決めを行うことができる。
【０５１２】
一方、ステップＳ３５０の微調整（位置調整処理）を第２の実施の形態の微調整で行う場合には、次のように行うことにより、緑色用の液晶ライトバルブ２５と、赤色用の液晶ライトバルブ２４と、青色用の液晶ライトバルブ２６とにより形成された各画像が重なるように、赤色用の液晶ライトバルブ２４および青色用の液晶ライトバルブ２６の位置決めを行うことができる。
【０５１３】
まず、赤色用の液晶ライトバルブ２４および青色用の液晶ライトバルブ２６の位置決めを行うに先立って、緑色用の液晶ライトバルブ２５の投影領域１１０をカメラ６１〜６４でそれぞれ撮像し、各画像データをメモリー４に記憶する。
【０５１４】
そして、メモリー４から前記各画像データをそれぞれ読み出し、前述したエッジ処理により、各特定位置のＸ座標およびＹ座標を求める。得られた各特定位置のＸ座標およびＹ座標を、それぞれ、位置調整のうちの微調整における各目的位置のＸ座標およびＹ座標として設定する。
【０５１５】
これにより、緑色用の液晶ライトバルブ２５と、赤色用の液晶ライトバルブ２４と、青色用の液晶ライトバルブ２６とにより形成された各画像が重なるように、赤色用の液晶ライトバルブ２４および青色用の液晶ライトバルブ２６の位置決めを行うことができる。
【０５１６】
液晶ライトバルブ２４の位置決めが終了すると、前述したように、この液晶ライトバルブ２４は、光学ブロック２０に仮固定され、この後、本固定される。
【０５１７】
同様に、液晶ライトバルブ２６の位置決めが終了すると、前述したように、この液晶ライトバルブ２６は、光学ブロック２０に仮固定され、この後、本固定される。
【０５１８】
以上説明したように、本発明のライトバルブの位置決め方法によれば、各液晶ライトバルブ２４〜２６の位置決めが自動的に行われるので、それを手作業で行う場合に比べ、容易、迅速かつ確実に位置決めすることができる。
【０５１９】
また、位置決めを手作業で行う場合に比べ、精度良く、位置決めすることができる。
【０５２０】
特に、フォーカス調整用の投影領域１００と位置調整用の投影領域１１０とを設定して位置決めを行うので、フォーカス調整と位置調整で、カメラ６１〜６４を兼用することができる。
【０５２１】
このため、フォーカス調整専用のカメラと位置調整専用のカメラとを用いて位置決めを行う場合に比べ、カメラの台数を減少させることができ、これにより、位置決め装置１の構造を簡素化することができ、また、コストを低減することができる。
【０５２２】
また、フォーカス調整専用のカメラと位置調整専用のカメラとを用いて位置決めを行う場合に比べ、位置決め装置１の組み立て、特に、カメラ６１〜６４を設置するとき（組み付けるとき）のそのカメラの位置決めを容易に行うことができる。
【０５２３】
また、フォーカス調整用の投影領域１００と、位置調整用の投影領域１１０とを設定し、これらを切り替えて、フォーカス調整と位置調整とを行うので、汎用性が広く、容易に、多機種に対応することができる。
【０５２４】
また、フォーカス調整では、粗調整と微調整とを行うので、短時間で、精度良くフォーカス調整することができる。
【０５２５】
また、Ｘ軸方向成分の分散値Ｖｈが最大のときの液晶ライトバルブ２４〜２６のＺ軸方向の位置と、Ｙ軸方向成分の分散値Ｖｖが最大のときの液晶ライトバルブ２４〜２６のＺ軸方向の位置とを求め、これらに基づいて、図４２（ｄ）に示すフォーカスが合った状態のときの液晶ライトバルブ２４〜２６のＺ軸方向の位置を求めるので、レンズの収差の大小にかかわらず、フォーカス調整の精度を高くすることができる。
【０５２６】
また、カメラ６１の撮像領域６１１、カメラ６２の撮像領域６２１、カメラ６３の撮像領域６３１およびカメラ６４の撮像領域６４１が、それぞれ、図６に示すように、投影領域１００の角部１０１ａ付近、角部１０１ｂ付近、角部１０１ｃ付近および角部１０１ｄ付近に位置するようになっており、これらのすべての処理領域５５０において図４２（ｄ）に示すフォーカスが合った状態に近づくか、または、一致するように調整するので、スクリーン２上の投影領域１００のほぼ全域においてフォーカスが合う。すなわち、投影領域１００のほぼ全域において高いコントラストが得られる。
【０５２７】
また、位置調整では、粗調整と微調整とを行うので、短時間で、精度良く位置調整を行うことができる。
【０５２８】
また、カメラ６１の撮像領域６１１、カメラ６２の撮像領域６２１、カメラ６３の撮像領域６３１およびカメラ６４の撮像領域６４１に、それぞれ、図６に示すように、投影領域１１０の角部１１１ａ、角部１１１ｂ、角部１１１ｃおよび角部１１１ｄが含まれ、これらのすべての角部に対して位置調整するので、正確に位置調整することができる。
【０５２９】
また、粗調整を行うことにより、スクリーン上に投影した画像が目的領域内に存在しない場合でも、かかる画像の角部を目的領域内に導入することができ、効率よく位置調整を行うことができる。これにより、投影領域が目的領域から離間したところに位置する場合でも、位置調整を容易に行うことができる。
【０５３０】
また、第１の実施の形態の微調整を行う場合には、スクリーン上に投影した画像が完全に長方形でない場合でも、正確に位置調整を行うことができる。
【０５３１】
また、位置調整のうちの微調整において、第２の実施の形態の微調整を行う場合には、輝度の積算値を利用する前述したエッジ処理により特定位置のＸ座標およびＹ座標を求めるので、正確に特定位置のＸ座標およびＹ座標を求めることができ、これにより位置調整の精度をさらに向上させることができる。
【０５３２】
そして、本発明の表示ユニットおよび投射型表示装置によれば、前述した位置決め方法により、液晶ライトバルブ２４、２５および２６が精度良く位置決めされているので、画像の全域においてコントラスト（画像の鮮明さ）が高く、色ずれ（画素ずれ）のないカラー画像をスクリーン上に投影することができる。
【０５３３】
次に、本発明のライトバルブの位置決め方法の他の実施例を説明する。なお、前述した実施例との共通点については説明を省略し、主な相違点を説明する。
【０５３４】
前述した実施例では、液晶ライトバルブ２４〜２６のフォーカス調整および位置調整をそれぞれ液晶ライトバルブ２４〜２６を作動させて行うが、この実施例では、液晶ライトバルブ２４〜２６のフォーカス調整をそれぞれ液晶ライトバルブ２４〜２６を作動させずに行い、液晶ライトバルブ２４〜２６の位置調整をそれぞれ液晶ライトバルブ２４〜２６を作動させて行う。
【０５３５】
具体的には、この実施例は、前述した実施例において、図７に示すフローチャートのステップＳ１０１を省略したものとなる。
【０５３６】
液晶ライトバルブ２４〜２６を作動させない場合、それぞれ、液晶ライトバルブ２４〜２６に照射された光は、その画素を透過し、スクリーン２上に投影される。
【０５３７】
よって、この実施例では、例えば、液晶ライトバルブ２５の有効画面領域に対応するスクリーン２上の領域を前述したフォーカス調整用の投影領域１００として設定する。
【０５３８】
なお、この場合には、図７のステップＳ１００において４台の照明装置７１〜７４を点灯させると、スクリーン２上の投影領域１００に、フォーカス調整用の投影画像１３１（厳密には、照明光が照射された部分）が投影される。
【０５３９】
一方、位置調整用の投影領域１１０は、前述した実施例と同様にして設定する。
【０５４０】
この位置決め方法でも前述した実施例と同様の効果が得られる。
【０５４１】
以上、本発明のライトバルブの位置決め方法、表示ユニットおよび投射型表示装置を、図示の実施例に基づいて説明したが、本発明はこれに限定されるものではない。
【０５４２】
例えば、本発明では、用いる位置決め装置の構造は、図示のものに限定されない。
【０５４３】
また、本発明では、第１の投影領域の形状、第２の投影領域の形状は、それぞれ、四角形には限定されず、この他、例えば、三角形、五角形等の多角形等でもよい。
【０５４４】
また、本発明では、フォーカス調整において撮像される所定領域の位置と、位置調整において撮像される所定領域の位置は、それぞれ、前記実施例には限定されない。
【０５４５】
また、本発明では、カメラの台数、すなわち、フォーカス調整において撮像される所定領域の数と、位置調整において撮像される所定領域の数は、それぞれ、前記実施例には限定されない。
【０５４６】
例えば、フォーカス調整や位置調整において撮像される所定領域は、３箇所以下でもよく、また、５箇所以上でもよい。
【０５４７】
但し、フォーカス調整、位置調整において撮像される所定領域は、３箇所以上（但し、そのすべてが同一直線上に存在する場合を除く）が好ましく、４または５箇所（但し、そのすべてが同一直線上に存在する場合を除く）がより好ましい。
【０５４８】
フォーカス調整、位置調整において撮像される所定領域を３箇所以上に設定することにより、スクリーン上に投影された第１の投影領域のほぼ全域においてフォーカスが合った状態のときのライトバルブのＺ軸方向の位置および姿勢と、現在のライトバルブのＺ軸方向の位置および姿勢とのずれを検出することができる。これにより、前記第１の投影領域のほぼ全域においてフォーカスが合うように（第１の投影領域のほぼ全域において高いコントラストが得られるように）、フォーカス調整することができる。
【０５４９】
フォーカス調整、位置調整において撮像される所定領域を３箇所に設定したときの実施例を図５１および図５２に示し、フォーカス調整、位置調整において撮像される所定領域を４箇所に設定したときの実施例を図５３に示す。
【０５５０】
図５１に示すように、この実施例では、図示しない３台のカメラが設置されており、これらのカメラの撮像領域４１１、４１２および４１３は、それぞれ、投影領域１００の内側で、かつ、投影領域１１０の非投影領域１１５との境界部１６を含むように設定されている。
【０５５１】
具体的には、撮像領域４１１は、辺１０４ａの近傍であって、かつ、辺１０３ａと辺１０３ｂの中間に位置し、辺１１４ａの中間部を含むように設定されている。
【０５５２】
また、撮像領域４１２は、角部１０１ａ付近に位置し、角部１１１ａを含むように設定されている。
【０５５３】
また、撮像領域４１３は、角部１０１ｂ付近に位置し、角部１１１ｂを含むように設定されている。
【０５５４】
この場合には、撮像領域４１１の画像データからは、撮像領域４１１のうちの特定位置のＹ座標が求まり、撮像領域４１２の画像データからは、撮像領域４１２のうちの特定位置のＸ座標およびＹ座標が求まり、撮像領域４１３の画像データからは、撮像領域４１３のうちの特定位置のＸ座標およびＹ座標が求まる。
【０５５５】
従って、これらの情報に基づいて液晶ライトバルブを変位させることにより位置調整する。
【０５５６】
図５２に示すように、この実施例では、図示しない３台のカメラが設置されており、これらのカメラの撮像領域４２１、４２２および４２３は、それぞれ、投影領域１００の内側で、かつ、投影領域１１０の非投影領域１１５との境界部１６を含むように設定されている。
【０５５７】
具体的には、撮像領域４２１は、辺１０４ｂの近傍であって、かつ、辺１０３ａと辺１０３ｂの中間に位置し、辺１１４ｂの中間部を含むように設定されている。
【０５５８】
また、撮像領域４２２は、角部１０１ｃ付近に位置し、角部１１１ｃを含むように設定されている。
【０５５９】
また、撮像領域４２３は、角部１０１ｄ付近に位置し、角部１１１ｄを含むように設定されている。
【０５６０】
この場合には、撮像領域４２１の画像データからは、撮像領域４２１のうちの特定位置のＹ座標が求まり、撮像領域４２２の画像データからは、撮像領域４２２のうちの特定位置のＸ座標およびＹ座標が求まり、撮像領域４２３の画像データからは、撮像領域４２３のうちの特定位置のＸ座標およびＹ座標が求まる。
【０５６１】
従って、これらの情報に基づいて液晶ライトバルブを変位させることにより位置調整する。
【０５６２】
図５３に示すように、この実施例では、図示しない４台のカメラが設置されており、これらのカメラの撮像領域４３１、４３２および４３３は、それぞれ、投影領域１００の内側で、かつ、投影領域１１０の非投影領域１１５との境界部１６を含むように設定されている。
【０５６３】
具体的には、撮像領域４３１は、角部１０１ａ付近に位置し、辺１１４ｂのうちの角部１１１ａの近傍の部分を含むように設定されている。
【０５６４】
また、撮像領域４３２は、角部１０１ｂ付近に位置し、辺１１４ｂのうちの角部１１１ｂの近傍の部分を含むように設定されている。
【０５６５】
また、撮像領域４３３は、角部１０１ｃ付近に位置し、角部１１１ｃを含むように設定されている。
【０５６６】
また、撮像領域４３４は、角部１０１ｄ付近に位置し、角部１１１ｄを含むように設定されている。
【０５６７】
この場合には、撮像領域４３１の画像データからは、撮像領域４３１のうちの特定位置のＹ座標が求まり、撮像領域４３２の画像データからは、撮像領域４３２のうちの特定位置のＹ座標が求まり、撮像領域４３３の画像データからは、撮像領域４３３のうちの特定位置のＸ座標およびＹ座標が求まり、撮像領域４３４の画像データからは、撮像領域４３４のうちの特定位置のＸ座標およびＹ座標が求まる。
【０５６８】
従って、これらの情報に基づいて液晶ライトバルブを変位させることにより位置調整する。
【０５６９】
なお、この他、例えば、撮像領域を辺１０３ａの近傍であって、かつ、辺１０４ａと辺１０４ｂの中間に位置させ、辺１１３ａの中間部を含むように設定してもよい。この場合には、前記撮像領域の画像データからは、その撮像領域のうちの特定位置のＸ座標が求まる。
【０５７０】
また、例えば、撮像領域を辺１０３ｂの近傍であって、かつ、辺１０４ａと辺１０４ｂの中間に位置させ、辺１１３ｂの中間部を含むように設定してもよい。この場合には、前記撮像領域の画像データからは、その撮像領域のうちの特定位置のＸ座標が求まる。
【０５７１】
また、前記実施例では、第１のフォーカス調整（フォーカスの粗調整）、第２のフォーカス調整（フォーカスの微調整）、第１の位置調整（位置の粗調整）、第２の位置調整（位置の微調整）の順番で、ライトバルブの位置決めを行っているが、本発明では、この順番に限らず、例えば、第１のフォーカス調整（フォーカスの粗調整）、第１の位置調整（位置の粗調整）、第２のフォーカス調整（フォーカスの微調整）、第２の位置調整（位置の微調整）の順番で、ライトバルブの位置決めを行ってもよい。
【０５７２】
また、前記実施例では、ライトバルブが、液晶ライトバルブで構成されているが、本発明では、これに限らず、例えば、ＤＭＤ（Digital Micromirror Device）を用いたライトバルブで構成されていてもよい。なお、ＤＭＤを用いたライトバルブの場合には、そのＤＭＤにより所定のパターン（明暗パターン）を形成し、そのパターンをスクリーン上に投影して位置決めを行う。
【０５７３】
また、前記第１の実施の形態のステップＳ３５０の微調整において、四頂点位置計測処理（処理Ｓ９０ｄ）では、エッジ処理を行い特定位置を検出し、かかるエッジ処理で検出した特定位置に基づいて、前記第１の処理（処理Ｓ３５Ａ）と、第２の処理（処理Ｓ３５Ｂ）と、第３の処理（処理Ｓ３５Ｃ）とを行ってもよい。
【０５７４】
【発明の効果】
以上説明したように、本発明のライトバルブの位置決め方法によれば、容易、迅速、確実に、かつ精度良く位置決めすることができる。
【０５７５】
特に、フォーカス調整と位置調整とに、共通（同一）のカメラを用いて位置決めを行うので、フォーカス調整専用のカメラと位置調整専用のカメラとを用いて位置決めを行う場合に比べ、カメラの台数を減少させることができ、これにより、位置決め装置の構造を簡素化することができる。
【０５７６】
また、フォーカス調整専用のカメラと位置調整専用のカメラとを用いて位置決めを行う場合に比べ、位置決め装置の組み立て、特に、カメラを設置するときのそのカメラの位置決めを容易に行うことができる。
【０５７７】
また、第１の投影領域と第２の投影領域とを設定し、これらを切り替えて、フォーカス調整と位置調整とを行うので、汎用性が広く、容易に、多機種に対応することができる。
【０５７８】
また、フォーカス調整では、粗調整と微調整とを行うので、短時間で、精度良くフォーカス調整を行うことができ、また、位置調整では、粗調整と微調整とを行うので、短時間で、精度良く位置調整を行うことができる。
【０５７９】
そして、本発明の表示ユニットおよび投射型表示装置によれば、赤色、緑色および青色に対応した３つのライトバルブが精度良く位置決めされているので、コントラストが高く、色ずれのないカラー画像をスクリーン上に投影することができる。
【図面の簡単な説明】
【図１】本発明のライトバルブの位置決め方法に用いる位置決め装置の構成例を模式的に示す側面図である。
【図２】図１に示す位置決め装置の回路構成を示すブロック図である。
【図３】本発明における投射型表示装置の光学ヘッド部（各液晶ライトバルブおよび光学系の一部）を示す断面図である。
【図４】本発明におけるダイクロイックプリズムと、緑色に対応した液晶ライトバルブと、支持部材とを示す分解斜視図である。
【図５】図１に示す位置決め装置のチャックで挟持された液晶ライトバルブを模式的に示す図である。
【図６】本発明における液晶ライトバルブによるスクリーン上の各投影領域と、各カメラの撮像領域とを模式的に示す図である。
【図７】本発明におけるフォーカス調整の際の位置決め装置の制御手段の制御動作を示すフローチャートである。
【図８】本発明におけるフォーカス調整の際の位置決め装置の制御手段の制御動作を示すフローチャートである。
【図９】本発明におけるフォーカス調整の際の位置決め装置の制御手段の制御動作を示すフローチャートである。
【図１０】本発明における位置調整（アライメント調整）の際の位置決め装置の制御手段の制御動作を示すフローチャートである。
【図１１】本発明における４つのパターンを模式的に示す図である。
【図１２】本発明における２つのパターンを模式的に示す図である。
【図１３】本発明における位置調整（アライメント調整）における粗調整の際の位置決め装置の制御手段の制御動作を示すフローチャートである。
【図１４】本発明における位置調整（アライメント調整）における粗調整の際の位置決め装置の制御手段の制御動作を示すフローチャートである。
【図１５】本発明における位置調整（アライメント調整）における粗調整の際の位置決め装置の制御手段の制御動作を示すフローチャートである。
【図１６】本発明における位置調整（アライメント調整）における粗調整の際の位置決め装置の制御手段の制御動作を示すフローチャートである。
【図１７】本発明における位置調整（アライメント調整）における第１の実施の形態の微調整の際の位置決め装置の制御手段の制御動作を示すフローチャートである。
【図１８】本発明における位置調整（アライメント調整）における第１の実施の形態の微調整の際の位置決め装置の制御手段の制御動作を示すフローチャートである。
【図１９】本発明における位置調整（アライメント調整）における粗調整を説明するための図である。
【図２０】本発明における位置調整（アライメント調整）における粗調整を説明するための図である。
【図２１】本発明における位置調整（アライメント調整）における粗調整を説明するための図である。
【図２２】本発明における位置調整（アライメント調整）における粗調整を説明するための図である。
【図２３】本発明における位置調整（アライメント調整）における粗調整を説明するための図である。
【図２４】本発明における位置調整（アライメント調整）における粗調整を説明するための図である。
【図２５】本発明における位置調整（アライメント調整）における第１の実施の形態の微調整を説明するための図である。
【図２６】本発明における他の４つのパターンを模式的に示す図である。
【図２７】本発明における他の２つのパターンを模式的に示す図である。
【図２８】本発明における位置調整（アライメント調整）における第２の実施の形態の微調整を説明するための図である。
【図２９】本発明におけるエッジ処理における位置決め装置の制御手段の制御動作を示すフローチャートである。
【図３０】本発明におけるエッジ処理を説明するための図である。
【図３１】本発明におけるエッジ処理を説明するための図である。
【図３２】本発明におけるエッジ処理を説明するための図である。
【図３３】本発明における第１の波形および第２の波形を示す図である。
【図３４】本発明における撮像領域と、処理領域とを模式的に示す図である。
【図３５】本発明における処理領域の一部分を模式的に示す図である。
【図３６】本発明における処理領域の一部分と、その部分に対応するＹ軸方向の輝度の積算値のグラフとを示す図である。
【図３７】本発明における処理領域の一部分と、その部分に対応するＹ軸方向の輝度の積算値のグラフとを示す図である。
【図３８】本発明における処理領域の一部分と、その部分に対応するＸ軸方向の輝度の積算値のグラフとを示す図である。
【図３９】本発明における処理領域の一部分と、その部分に対応するＸ軸方向の輝度の積算値のグラフとを示す図である。
【図４０】本発明におけるフォーカス調整の際の液晶ライトバルブの移動を説明するための模式図である。
【図４１】本発明におけるカメラで撮像した画像についての分散値Ｖｈ、Ｖｖと、前記分散値Ｖｈ、Ｖｖを取得したときの液晶ライトバルブのＺ軸方向の位置との関係を示すグラフである。
【図４２】本発明における液晶ライトバルブのＺ軸方向の位置を変えたときの処理領域内の画像を模式的に示す図である。
【図４３】本発明におけるフォーカス調整用の投影画像の構成例を模式的に示す図である。
【図４４】本発明における位置調整用の投影画像の構成例を模式的に示す図である。
【図４５】本発明におけるフォーカス調整用の投影領域、位置調整用の投影領域の構成例を模式的に示す図である。
【図４６】本発明におけるフォーカス調整用の投影領域、位置調整用の投影領域の構成例を模式的に示す図である。
【図４７】本発明におけるフォーカス調整用の投影領域、位置調整用の投影領域の構成例を模式的に示す図である。
【図４８】本発明におけるフォーカス調整用の投影領域、位置調整用の投影領域の構成例を模式的に示す図である。
【図４９】本発明におけるフォーカス調整用の投影領域、位置調整用の投影領域の構成例を模式的に示す図である。
【図５０】本発明におけるフォーカス調整用の投影領域、位置調整用の投影領域の構成例を模式的に示す図である。
【図５１】本発明における液晶ライトバルブによるスクリーン上の各投影領域と、各カメラの撮像領域（３箇所）とを模式的に示す図である。
【図５２】本発明における液晶ライトバルブによるスクリーン上の各投影領域と、各カメラの撮像領域（３箇所）とを模式的に示す図である。
【図５３】本発明における液晶ライトバルブによるスクリーン上の各投影領域と、各カメラの撮像領域（４箇所）とを模式的に示す図である。
【図５４】従来の投射型表示装置の光学系を模式的に示す図である。
【符号の説明】
１ 位置決め装置
２ スクリーン
３ 制御手段
４ メモリー
５５０ 処理領域
５５１ 画素部
５５２ 間隙部
５５３ Ｙ軸方向間隙部
５５４ Ｘ軸方向間隙部
５５５ 共通間隙部
５６０ 列
５７０ 行
６１〜６４ カメラ
６１１、６２１ 撮像領域
６１２ 辺
６３１、６４１ 撮像領域
６３２、６３３ 辺
６４３ 辺
７１〜７４ 照明装置
８ ３軸テーブル
８１ ３軸テーブル駆動機構
９ ３軸テーブル
９１ ３軸テーブル駆動機構
１１ チャック
１２ 支持部材
２０ 光学ブロック
２１ ダイクロイックプリズム
２１１、２１２ ダイクロイックミラー面
２１３〜２１５ 面
２１６ 出射面
２２ 投射レンズ
２３ 支持体
２４〜２６ 液晶ライトバルブ
２５１ 枠部材
２５２ 貫通孔
２５３ 切り欠き部
２７ 支持部材
２８ 固定板
２８１ 開口
２８２ ネジ孔
２９ 固定板
２９１ 開口
２９２ 貫通孔
２９３ 突起
３１ ネジ
３２ 楔
３３ 接着剤
４１１〜４１３ 撮像領域
４２１〜４２３ 撮像領域
４３１〜４３４ 撮像領域
１００ 投影領域
１０１ａ、１０１ｂ 角部
１０１ｃ、１０１ｄ 角部
１０３ａ、１０３ｂ 辺
１０４ａ、１０４ｂ 辺
１１０ 投影領域
１１１ａ、１１１ｂ 角部
１１１ｃ、１１１ｄ 角部
１１２ａ、１１２ｂ エッジ
１１２ｃ、１１２ｄ エッジ
１１３ａ、１１３ｂ 辺
１１４ａ、１１４ｂ 辺
１１５ 非投影領域
１１６ 境界部
１２１〜１２４ 位置
１２５ａ、１２５ｂ 中心
１２５ｃ、１２５ｄ 中心
１２６、１２７ 直線
１２８ 特定位置
１２９ａ、１２９ｂ 位置
１３１、１４１ 投影画像
３００ 投射型表示装置
３０１ 光源
３０２、３０３ インテグレータレンズ
３０４、３０６、３０９ ミラー
３０５、３０７、３０８ ダイクロイックミラー
３１０〜３１４ 集光レンズ
３１５ ダイクロイックプリズム
３１６〜３１８ 液晶ライトバルブ
３１９ 投射レンズ
３２０ スクリーン
Ｓ１００〜Ｓ１２０ ステップ
Ｓ１０ａ 処理
Ｓ１５０ ステップ
Ｓ２０１〜Ｓ２３２ ステップ
Ｓ３００ 粗調整
Ｓ３０Ａ〜Ｓ３０Ｈ 処理
Ｓ３０１〜Ｓ３２９ ステップ
Ｓ３５０ 微調整
Ｓ３５１〜Ｓ３５９ ステップ
Ｓ４０１〜Ｓ４１５ ステップ
Ｓ９０ａ〜Ｓ９０ｄ 処理
Ｓ９０１〜Ｓ９１０ ステップ
Ｓ９２１、Ｓ９２２ ステップ
Ｓ９３１、Ｓ９３２ ステップ
Ｓ９４１〜Ｓ９４８ ステップ[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a light valve positioning method for a projection display device, a display unit, and a projection display device.
[0002]
[Prior art]
A projection type display device using a liquid crystal light valve (liquid crystal light shutter array) is known.
[0003]
FIG. 54 is a diagram schematically showing an optical system of a conventional projection display apparatus.
[0004]
As shown in the figure, the projection display apparatus 300 reflects a light source 301, an illumination optical system composed of integrator lenses 302 and 303, mirrors 304, 306, and 309, red light and green light (blue). A dichroic mirror 305 that transmits only light, a dichroic mirror 307 that reflects only green light, a dichroic mirror that reflects only red light (or a mirror that reflects red light) 308, condenser lenses 310, 311, 312, 313, and 314, a color separation optical system (light guide optical system), three liquid crystal light valves 316, 317 and 318 corresponding to blue, green and red, a dichroic prism (color synthesis optical system) 315, and a projection lens (Projection optical system) 319.
[0005]
White light (white light beam) emitted from the light source 301 passes through the integrator lenses 302 and 303. The light intensity (luminance distribution) of this white light is made uniform by the integrator lenses 302 and 303.
[0006]
The white light transmitted through the integrator lenses 302 and 303 is reflected to the left in FIG. 54 by the mirror 304, and red light (R) and green light (G) of the reflected light are respectively reflected by the dichroic mirror 305 in FIG. The blue light (B) is reflected downward and passes through the dichroic mirror 305.
[0007]
The blue light transmitted through the dichroic mirror 305 is reflected downward in FIG. 54 by the mirror 306, and the reflected light passes through the condenser lens 310 and then enters the liquid crystal light valve 316 for blue.
[0008]
Of the red light and green light reflected by the dichroic mirror 305, green light is reflected by the dichroic mirror 307 to the left in FIG. 54, and the red light passes through the dichroic mirror 307.
[0009]
The green light reflected by the dichroic mirror 307 passes through the condenser lens 311 and then enters the green liquid crystal light valve 317.
[0010]
Further, the red light transmitted through the dichroic mirror 307 is reflected by the dichroic mirror (or mirror) 308 to the left side in FIG. 54, and the reflected light is reflected by the mirror 309 to the upper side in FIG. The red light passes through the condenser lenses 312, 313 and 314 and then enters the red liquid crystal light valve 318.
[0011]
As described above, the white light emitted from the light source 301 is separated into the three primary colors of red, green, and blue by the color separation optical system, and is guided to the corresponding liquid crystal light valve and enters.
[0012]
These blue light, green light, and red light are modulated by the liquid crystal light valves 316, 317, and 318, respectively, thereby forming a blue image, a green image, and a red image, respectively.
[0013]
The light of each color from the liquid crystal light valves 316, 317 and 318, that is, the respective images formed by the liquid crystal light valves 316, 317 and 318 are synthesized by the dichroic prism 315, thereby forming a color image. This image is projected (enlarged projection) onto the screen 320 installed at a predetermined position by the projection lens 319.
[0014]
When assembling the projection display device 300 described above, the three liquid crystal light valves 316, 306, so that an image having high contrast (clearness of image) and no color shift (pixel shift) can be displayed on the screen 320. Positioning of 317 and 318, that is, focus adjustment and position adjustment of the three liquid crystal light valves 316, 317 and 318 are performed, respectively.
[0015]
In the focus adjustment, an adjustment image that makes it easy to recognize the contrast is projected, and the operator confirms the contrast with the naked eye, and uses an adjustment tool to displace and fix the liquid crystal light valve so that the contrast becomes the highest. The method of doing is taken.
[0016]
In the position adjustment, an adjustment image that easily recognizes color misregistration is projected, and an operator checks the pixel misregistration with the naked eye, and uses an adjustment tool to adjust the liquid crystal light so that the color misregistration is minimized. A method of displacing and fixing the valve is employed.
[0017]
Conventionally, however, the positioning of the liquid crystal light valve is performed manually, which is very time-consuming and takes a long time even by a skilled person.
[0018]
In addition, since contrast and color shift are observed with the naked eye, there is a drawback that positioning accuracy is poor.
[0019]
In addition, since the screen on which the image is projected is separated from the position of the liquid crystal light valve to be positioned, it is necessary to go back and forth between the screen and the liquid crystal light valve many times when positioning by one person. And it takes a very long time to work.
[0020]
When positioning by two people, one worker is located near the screen, observes the projected image, conveys the information to the other worker, and the worker who receives the information Since the liquid crystal light valve is displaced, not only does the number of workers increase, but information may not be accurately transmitted between the workers, which is not reliable.
[0021]
[Problems to be solved by the invention]
An object of the present invention is to provide a light valve positioning method capable of easily, quickly, reliably and accurately positioning a light valve of a projection display device, a display unit having a light valve positioned by the positioning method, and a projection. It is to provide a mold display device.
[0022]
[Means for Solving the Problems]
Such an object is achieved by the present inventions (1) to (24) below.
[0023]
(1) A positioning method for positioning the light valve of a projection display device that projects an image formed by a light valve by a projection optical system,
Each predetermined area projected on the screen is imaged with the same camera for each predetermined area to obtain an electronic image, and focus adjustment and position adjustment of the light valve are performed based on each electronic image. A light valve positioning method characterized by comprising:
[0024]
(2) A positioning method for positioning the light valve of a projection display device that projects an image formed by a light valve by a projection optical system,
A focus that displaces the light valve so that an electronic image is obtained by imaging a predetermined area of the first projection area projected on the screen by a camera, and the focus state of the electronic image approaches a target state. Make adjustments
A position at which the light valve is displaced so that a predetermined area in the second projection area projected on the screen is captured by the camera to obtain an electronic image, and a specific position in the electronic image approaches a target position. A light valve positioning method characterized by performing adjustment.
[0025]
(3) A positioning method for positioning the light valve of a projection display device that projects an image formed by a light valve by a projection optical system,
An electronic image is obtained by imaging a predetermined area of the first projection area projected on the screen by a camera, and the light valve is displaced so that the focus state of the electronic image approaches a target state. Adjust the focus of 1
After the first focus adjustment, the camera captures a predetermined area of the first projection area projected on the screen to obtain an electronic image, and the focus state of the electronic image becomes a target state. Perform a second focus adjustment to displace the light valve so that it is closer,
The camera captures a predetermined area of the second projection area projected on the screen to obtain an electronic image, and displaces the light valve so that a specific position in the electronic image approaches a target position. Adjust position 1 and
After the first position adjustment, the camera captures a predetermined area of the second projection area projected on the screen to obtain an electronic image, and the specific position in the electronic image is closer to the target position. The light valve positioning method is characterized by performing a second position adjustment for displacing the light valve as described above.
[0026]
(4) The light valve positioning method according to (2) or (3), wherein the predetermined area in the focus adjustment of the light valve and the predetermined area in the position adjustment of the light valve are the same area on the screen. .
[0027]
(5) The light valve positioning method according to any one of (2) to (4), wherein the contour of the first projection region is located outside the contour of the second projection region.
[0028]
(6) The light valve positioning method according to any one of (2) to (5), wherein the first projection area is set so as to include the predetermined area in the first projection area.
[0029]
(7) The shape of the first projection area is a substantially quadrangular shape, and the first projection area is set so that the predetermined area in the first projection area is positioned in the vicinity of a corner portion thereof. The light valve positioning method according to (6).
[0030]
(8) Any one of (2) to (7), wherein the second projection area is set such that a boundary portion with the non-projection area is included in the predetermined area in the second projection area The light valve positioning method described in 1.
[0031]
(9) The shape of the second projection area is a substantially quadrangular shape, and the second projection area is set such that a corner thereof is included in the predetermined area in the second projection area. The light valve positioning method according to any one of (2) to (7).
[0032]
(10) The predetermined areas are set at four places, the shape of the first projection area is a substantially quadrangular shape, and the predetermined areas are located near the corners of the first projection area. The shape of the second projection area is substantially quadrangular, and the second projection area is set such that each corner is included in the predetermined area (6) The light valve positioning method described in 1.
[0033]
(11) The light valve positioning method according to any one of (2) to (9), wherein the predetermined area is set to three or more places (except when all of them are on the same straight line). . In this case, it is preferable that the predetermined areas are separated from each other.
[0034]
(12) The number of the cameras is the same as the number of the predetermined areas. The light valve according to any one of (2) to (11), wherein each of the cameras captures the corresponding predetermined area. Positioning method.
[0035]
(13) The displacement of the light valve in the focus adjustment of the light valve includes the rotation around the X axis, the rotation around the Y axis of the X axis, the Y axis, and the Z axis orthogonal to each other, and the Z axis direction. The light valve positioning method according to any one of (2) to (12), wherein
[0036]
(14) The displacement of the light valve in the position adjustment of the light valve is the movement in the X-axis direction of the X-axis, the Y-axis, and the Z-axis orthogonal to each other, the movement in the Y-axis direction, The light valve positioning method according to any one of the above (2) to (13), which is rotation.
[0037]
(15) The light valve positioning method according to any one of (1) to (14), wherein the light valve is a liquid crystal light valve.
[0038]
(16) The light valve positioning method according to (15), wherein focus adjustment of the light valve is performed without operating the light valve, and position adjustment of the light valve is performed by operating the light valve.
[0039]
(17) The light valve positioning method according to (15), wherein focus adjustment and position adjustment of the light valve are performed by operating the light valve, respectively.
[0040]
(18) The light valve positioning method according to any one of (1) to (17), wherein the position of the light valve is adjusted after focus adjustment of the light valve.
[0041]
(19) The light valve positioning method according to any one of (1) to (18), wherein the projection display device includes three light valves corresponding to red, green, and blue.
[0042]
(20) The light valve positioning method according to (19), wherein the positioning is performed for each of the three light valves.
[0043]
(21) The light valve positioning method according to (19) or (20), wherein the positioning is performed so that images formed by the three light valves overlap.
[0044]
(22) The light valve corresponding to the green color is positioned, and the image formed by the light valve is formed by the light valve corresponding to the red color and the light valve corresponding to the blue color. The light valve positioning method according to any one of (19) to (21), wherein the light valve corresponding to the red color and the light valve corresponding to the blue color are positioned so as to overlap with an image.
[0045]
(23) The light bulb is positioned by the light valve positioning method according to any one of the above (1) to (22), and three light valves corresponding to red, green, and blue forming an image are combined with each image. A display unit comprising a color synthesis optical system.
[0046]
(24) Three light valves corresponding to red, green, and blue, which are positioned by the light valve positioning method according to any one of (1) to (22) and form an image, a light source, and the light source Are separated into red, green, and blue light, a color separation optical system that guides each light to the corresponding light valve, a color synthesis optical system that synthesizes the images, and a projection of the synthesized image And a projection optical system.
[0047]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a light valve positioning method, a display unit, and a projection display device according to the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.
[0048]
FIG. 1 is a side view schematically showing a configuration example of a positioning device used in the light valve positioning method of the present invention, and FIG. 2 is a block diagram showing a circuit configuration of the positioning device shown in FIG.
[0049]
The positioning device 1 shown in these figures is for positioning a light valve (light shutter array) of a projection display device (for example, a liquid crystal projector), that is, focus adjustment (contrast of three light valves corresponding to red, green and blue). Adjustment) and position adjustment (alignment adjustment).
[0050]
First, a projection display device will be described.
[0051]
FIG. 3 is a cross-sectional view showing an optical head portion (each liquid crystal light valve and a part of the optical system) of the projection display device, and FIG. 4 shows a dichroic prism, a liquid crystal light valve corresponding to green, and a support member. It is a disassembled perspective view shown.
[0052]
As shown in FIG. 1 and FIG. 3, the projection display device corresponds to a red light source (a light guide optical system) including a light source (not shown), a plurality of dichroic mirrors (not shown), and red (for red). ) Liquid crystal light valve (liquid crystal light shutter array) 24, liquid crystal light valve (liquid crystal light shutter array) 25 corresponding to green (for green), and liquid crystal light valve (liquid crystal light shutter for blue) corresponding to blue Array) 26, a dichroic prism (color combining optical system) 21 on which a dichroic mirror surface 211 reflecting only red light and a dichroic mirror surface 212 reflecting only blue light are formed, and a projection lens (projection optical system) 22 And an L-shaped support body 23.
[0053]
The dichroic prism 21 and the projection lens 22 are each fixedly installed on the support 23.
[0054]
Further, the three liquid crystal light valves 24, 25, and 26 are respectively connected to the upper surface 213 in FIG. 3, the right surface 214 in FIG. 3, and the lower surface in FIG. 215.
[0055]
The liquid crystal light valve 25 for green has pixels (light shutters) (not shown) arranged in the X axis direction and the Y axis direction orthogonal to each other.
[0056]
In this case, the X-axis direction and the Y-axis direction respectively coincide with the X-axis direction and the Y-axis direction shown in FIG. 5 when the liquid crystal light valve 25 is positioned by the positioning device 1 described later.
[0057]
The liquid crystal light valve 24 for red has pixels (light shutters) (not shown) arranged in the X axis direction and the Y axis direction orthogonal to each other.
[0058]
In this case, the X-axis direction and the Y-axis direction respectively coincide with the X-axis direction and the Y-axis direction shown in FIG. 5 when the liquid crystal light valve 24 is positioned by the positioning device 1 described later.
[0059]
The blue liquid crystal light valve 26 has pixels (light shutters) (not shown) arranged in the X-axis direction and the Y-axis direction orthogonal to each other.
[0060]
In this case, the X-axis direction and the Y-axis direction respectively coincide with the X-axis direction and the Y-axis direction shown in FIG. 5 when the liquid crystal light valve 26 is positioned by the positioning device 1 described later.
[0061]
Since the structure of each support member 27 is the same, the support member 27 that supports (fixes) the green liquid crystal light valve 25 will be typically described.
[0062]
As shown in FIG. 4, the support member 27 includes a fixing plate 28 positioned on the dichroic prism 21 side, a fixing plate 29 positioned on the liquid crystal light valve 25 side, and four screws for fixing these fixing plates 28 and 29. 31.
[0063]
A rectangular opening 281 for passing light is formed at the center of the fixed plate 28. Screw holes 282 that are screwed into the screws 31 are formed at the four corners of the fixing plate 28.
[0064]
A rectangular opening 291 for passing light is formed at the center of the fixed plate 29. In the positions corresponding to the screw holes 282 at the four corners of the fixing plate 29, through holes 292 having a diameter smaller than the head of the screw 31 and into which the screw 31 is inserted are formed. Further, in the vicinity of each corner of the opening 291 of the fixed plate 29, a protrusion 293 is provided so as to protrude to the opposite side of the dichroic prism 21.
[0065]
The fixed plate 28 and the fixed plate 29 are bonded to the surface 214 of the prism 21 with an adhesive 33 while being fixed with four screws 31.
[0066]
Through holes 252 into which the protrusions 293 are inserted are formed at positions corresponding to the protrusions 293 at the four corners of the frame member 251 of the liquid crystal light valve 25. The inner diameter of the through hole 252 is set so that the liquid crystal light valve 25 can be displaced during positioning described later.
[0067]
And the notch part 253 for inserting the wedge 32 mentioned later is provided in the left and right end surfaces in FIG. 4 of the frame member 251 respectively.
[0068]
The liquid crystal light valve 25 is positioned by a positioning device 1 to be described later in a state where each projection 293 of the fixing plate 29 is inserted into the corresponding through hole 252.
[0069]
When the positioning is completed, the liquid crystal light valve 25 is temporarily fixed by curing the adhesive previously injected into each through hole 252 of the frame member 251. As the adhesive for temporary fixing, for example, an ultraviolet curable adhesive or the like can be used.
[0070]
After this temporary fixing, two wedges (spacers) 32 are inserted from the notch 253 between the fixing plate 29 of the support member 27 and the frame member 251 of the liquid crystal light valve 25. The support member 27 and the liquid crystal light valve 25 are fixed (mainly fixed) with an adhesive via the wedges 32. As the fixing adhesive, for example, an ultraviolet curable adhesive can be used.
[0071]
Similarly to the green liquid crystal light valve 25 described above, the red liquid crystal light valve 24 and the blue liquid crystal light valve 26 are respectively positioned, temporarily fixed, and fixed by the positioning device 1 described later. .
[0072]
The liquid crystal light valves 24, 25, and 26 are respectively positioned with respect to the optical block 20 shown in FIG. 1, which includes the dichroic prism 21, the projection lens 22, and the support 23 on which three support members 27 are installed. Install (set) at a predetermined position in the posture.
[0073]
The optical block 20 and the liquid crystal light valves 24, 25 and 26 fixedly installed with respect to the dichroic prism 21 constitute a display unit of a projection display device.
[0074]
Next, the operation of the projection display device will be described.
[0075]
White light (white light flux) emitted from the light source is color-separated into three primary colors of red, green, and blue by a color separation optical system. As shown in FIG. 3, red light, green light, and blue light are respectively The liquid crystal light valve 24 for red, the liquid crystal light valve 25 for green, and the liquid crystal light valve 26 for blue are led.
[0076]
The red light enters the liquid crystal light valve 24 and is modulated by the liquid crystal light valve 24, thereby forming a red image. At this time, each pixel of the liquid crystal light valve 24 is subjected to switching control (ON / OFF) by a drive circuit (drive means) (not shown) that operates based on a red image signal.
[0077]
Similarly, green light and blue light are incident on the liquid crystal light valves 25 and 26, respectively, and modulated by the liquid crystal light valves 25 and 26, whereby a green image and a blue image are formed. At this time, each pixel of the liquid crystal light valve 25 is controlled by a drive circuit (not shown) that operates based on the green image signal, and each pixel of the liquid crystal light valve 26 operates based on the blue image signal. Switching control is performed by a driving circuit (not shown).
[0078]
As shown in FIG. 3, the red image formed by the liquid crystal light valve 24, that is, red light from the liquid crystal light valve 24 is incident on the dichroic prism 21 from the surface 213, and is reflected by the dichroic mirror surface 211 in FIG. 3. The light is reflected to the left, passes through the dichroic mirror surface 212, and exits from the exit surface 216.
[0079]
Further, the green image formed by the liquid crystal light valve 25, that is, the green light from the liquid crystal light valve 25, enters the dichroic prism 21 from the surface 214, passes through the dichroic mirror surfaces 211 and 212, and exits. The light exits from the surface 216.
[0080]
Further, the blue image formed by the liquid crystal light valve 26, that is, the blue light from the liquid crystal light valve 26 is incident on the dichroic prism 21 from the surface 215, and is reflected by the dichroic mirror surface 212 to the left in FIG. The light passes through the dichroic mirror surface 211 and exits from the exit surface 216.
[0081]
Thus, the light of each color from the liquid crystal light valves 24, 25 and 26, that is, the images formed by the liquid crystal light valves 24, 25 and 26 are synthesized by the dichroic prism 21, thereby forming a color image. Is done. This image is projected (enlarged projection) on a screen (not shown) installed at a predetermined position by the projection lens 22.
[0082]
Next, the positioning device 1 used in the light valve positioning method of the present invention will be described. In the description of the structure of the positioning device 1, the green liquid crystal light valve 25 is representatively described.
[0083]
As shown in FIGS. 1 and 2, the positioning device 1 includes a chuck 11 that holds liquid crystal light valves 24, 25, and 26, a support member 12 that supports the chuck 11, and a three-axis table (displacement means) for focus adjustment. ) 8, a three-axis table (displacement means) 9 for position adjustment (for alignment adjustment), four cameras (video cameras) 61, 62, 63 and 64 capable of forming an electronic image (image data), There are four lighting devices 71, 72, 73 and 74.
[0084]
Each of the cameras 61 to 64 is fixedly installed at a predetermined position. The cameras 61 to 64 are commonly used for focus adjustment and position adjustment, which will be described later, and the number of the cameras 61 to 64 is the same as the number of areas imaged in the focus adjustment and the number of areas imaged in the position adjustment.
[0085]
As shown in FIG. 1, a triaxial table 9 is supported by a triaxial table 8, a support member 12 is supported by the triaxial table 9, and a chuck 11 is installed at the tip of the support member 12.
[0086]
FIG. 5 is a diagram schematically showing the liquid crystal light valve 25 held by the chuck 11 of the positioning device 1.
[0087]
As shown in the figure, an X axis, a Y axis, and a Z axis (XYZ coordinates) orthogonal to each other are assumed.
[0088]
The focus adjustment triaxial table 8 is configured to move in the Z axis direction, rotate in both directions in the H direction (around the Y axis), and rotate in both directions in the V direction (around the X axis). Has been.
[0089]
When the three-axis table 8 moves in the Z-axis direction, the liquid crystal light valve 25 moves in the Z-axis direction together with the three-axis table 8. When the triaxial table 8 rotates in the H direction, the liquid crystal light valve 25 rotates in the H direction together with the triaxial table 8. When the triaxial table 8 rotates in the V direction, the liquid crystal light valve 25 rotates in the V direction together with the triaxial table 8.
[0090]
The displacement of the three-axis table 8, that is, the movement in the Z-axis direction and the rotation in the H-direction and the V-direction are each controlled by the control means 3 via a three-axis table drive mechanism 81 described later.
[0091]
Further, the position adjusting triaxial table 9 is configured to move in the X axis direction and the Y axis direction and to rotate in both directions in the W direction (around the Z axis).
[0092]
When the triaxial table 9 moves in the X axis direction, the liquid crystal light valve 25 moves in the X axis direction together with the triaxial table 9. When the triaxial table 9 moves in the Y axis direction, the liquid crystal light valve 25 moves in the Y axis direction together with the triaxial table 9. When the triaxial table 9 rotates in the W direction, the liquid crystal light valve 25 rotates in the W direction together with the triaxial table 9.
[0093]
The displacement of the three-axis table 9, that is, movement in the X-axis direction and Y-axis direction, and rotation in the W-direction are controlled by the control means 3 via a three-axis table drive mechanism 91 described later.
[0094]
Further, as shown in FIG. 1, the four lighting devices 71, 72, 73 and 74 are installed so as to be located on the back side (right side in FIG. 1) of the liquid crystal light valve 25 sandwiched between the chucks 11, respectively. Has been. The illumination ranges of the respective illumination devices 71 to 74 are set so as to cover at least imaging areas described later of the cameras 61 to 64, respectively.
[0095]
A screen 2 is installed at a position separated from the optical block 20 installed in the positioning device 1 by a predetermined distance.
[0096]
The screen 2 is not limited to a general screen, and may be any screen that can display a projection image (can function as a screen).
[0097]
In the present embodiment, each of the cameras 61 to 64 is installed on the surface side of the screen 2 (right side in FIG. 1).
[0098]
When the screen 2 is, for example, a reflection type (reflection type screen), each of the cameras 61 to 64 is disposed on the right side of the screen 2 in FIG. When the screen 2 is, for example, a transmission type (transmission type screen), the cameras 61 to 64 are arranged on the left side of the screen 2 in FIG. The image is taken from the left side in FIG.
[0099]
FIG. 6 shows a focus adjustment projection area (first projection area) and a position adjustment projection area (second projection area) on the screen 2 by the liquid crystal light valve 25, and imaging areas of the cameras 61 to 64. FIG.
[0100]
As shown in the figure, the imaging area 611 of the camera 61, the imaging area 621 of the camera 62, the imaging area 631 of the camera 63, and the imaging area 641 of the camera 64 are each substantially rectangular (quadrangle).
[0101]
As shown in FIG. 6, the positions and orientations of the imaging regions 611 to 641 are respectively located at the four vertices of a predetermined rectangle (rectangle), and the imaging regions 611 are located at the centers of the imaging regions 611 to 641. The corresponding sides of ˜641 are set to be parallel.
[0102]
As described above, since the cameras 61 to 64 are commonly used for focus adjustment and position adjustment, the imaging regions 611 to 641 are imaging regions for focus adjustment and position adjustment, respectively. That is, the area on the screen 2 imaged at the time of focus adjustment and the area on the screen 2 imaged at the time of position adjustment are the same area.
[0103]
The focus adjustment projection area (first projection area) 100 is substantially rectangular (quadrangle).
[0104]
An area surrounded by a one-dot chain line in FIG. 6 is a projection area 100, and an image formed by the liquid crystal light valves 24 to 26 is projected onto the screen 2 during the focus adjustment described later. The region (range) of each projected image at that time is shown.
[0105]
That is, at the time of focus adjustment, as shown in FIG. 43, a focus adjustment projection image (first projection image) 131 (the hatched portion in FIG. 43) is projected onto the screen 2. However, when a part of the liquid crystal light valves 24 to 26 (for example, a part corresponding to a part including the imaging regions 611 to 641) is irradiated with light beams (light) from the illumination devices 71 to 74, respectively, A projection image of that portion of the projection image 131 is projected on the screen 2.
[0106]
Further, as shown in FIG. 6, the position adjustment projection area (second projection area) 110 is substantially rectangular (quadrangle).
[0107]
An area surrounded by a dotted line in FIG. 6 is a projection area 110, and this projection area 110 is obtained when an image formed by the liquid crystal light valves 24 to 26 is projected on the screen 2 during position adjustment described later. A region (range) of each projection image is shown.
[0108]
That is, at the time of position adjustment, as shown in FIG. 44, a position adjustment projection image (second projection image) 141 (the hatched portion in FIG. 44) is projected onto the screen 2. However, when a part of the liquid crystal light valves 24 to 26 (for example, a part corresponding to a part including the imaging regions 611 to 641) is irradiated with light beams (light) from the illumination devices 71 to 74, respectively, A projection image of that portion of the projection image 141 is projected onto the screen 2.
[0109]
As shown in FIG. 6, the projection area 110 (projection image 141) is included in the projection area 100 (projection image 131). That is, the side 103a of the projection area 100 is located on the left side of the side 113a of the projection area 110 in FIG. 6, and the side 103b of the projection area 100 is located on the right side of the side 113b of the projection area 110 in FIG. The side 104a of 100 is positioned below the side 114a of the projection area 110 in FIG. 6, and the side 104b of the projection area 100 is positioned above the side 114b of the projection area 110 in FIG. 6 (projection area 100). Is located outside the contour of the projection area 110).
[0110]
As shown in FIG. 6, the projection area 100 includes imaging areas 611 to 641, and in the vicinity of the corners 101 a, 101 b, 101 c, and 101 d of the projection area 100, the imaging areas 611 and 621, respectively. , 631 and 641 are positioned.
[0111]
On the other hand, as shown in FIG. 6, the projection area 110 has corner portions 111a, 111b, 111c and 111d (predetermined portions of the boundary portion 116 between the projection area 110 and the non-projection area 115). These are set so as to be included in the imaging regions 611, 621, 631 and 641, respectively.
[0112]
In this embodiment, the camera 61 that captures the upper left in FIG. 6 (corresponding to the imaging region 611) is “camera No. 1”, and the camera 62 that captures the upper right in FIG. No. 2 ”, the camera 63 that captures the lower left in FIG. 6 (corresponding to the imaging area 631) is“ camera No. 3 ”, and the camera 64 that captures the lower right in FIG. 6 (corresponding to the imaging area 641) is“ Camera No. 4 ”.
[0113]
In addition, when the shape of the projection areas 100 and 110 is set to a quadrangle, the quadrangle is not limited to the shape illustrated in FIGS. 6, 43, and 44, for example, FIG. 45, FIG. 46, FIG. 54, FIG. 49, and FIG. 50 also include shapes shown by hatching. In other words, the outline (outer outline) may be substantially rectangular.
[0114]
As shown in FIG. 2, the positioning device 1 includes a control unit 3, a memory 4, and triaxial table drive mechanisms 81 and 91.
[0115]
The control means 3 is usually composed of a microcomputer (CPU), the memory 4, the cameras 61, 62, 63 and 64, the illumination devices 71, 72, 73 and 74, the triaxial table drive mechanisms 81 and 91, and the like. The overall positioning device 1 is controlled and the drive circuits of the liquid crystal light valves 24, 25 and 26 to be positioned are controlled.
[0116]
The liquid crystal light valves 24, 25 and 26 may be displaced using a 6-axis table.
[0117]
Next, the light valve positioning method of the present invention (the operation of the positioning device 1) will be described.
[0118]
When the optical block 20 is placed at a predetermined position of the positioning device 1 and the positioning device 1 is operated, the positioning device 1 automatically positions each of the liquid crystal light valves 24, 25 and 26, and these are optically detected. Temporarily fixed to the block 20.
[0119]
In this embodiment, when the liquid crystal light valves 24, 25 and 26 are positioned, the green liquid crystal light valve 25 is first positioned, and thereafter the red liquid crystal light valve 24 and the blue liquid crystal light valve 24 are positioned. The light valve 26 is positioned.
[0120]
That is, first, the liquid crystal light valve 25 is positioned at a preset position, then the position of the liquid crystal light valve 25 is detected, and the liquid crystal light valves 24 and 26 are respectively positioned at positions corresponding to the detected positions. Position it.
[0121]
Further, when positioning each of the liquid crystal light valves 24, 25 and 26, first, focus adjustment (contrast adjustment) is performed, and then position adjustment (alignment adjustment) is performed.
[0122]
In focus adjustment, first, coarse adjustment (first focus adjustment) is performed, and then coarse adjustment is performed, and then fine adjustment (second focus adjustment) is performed. The focus adjustment of the green liquid crystal light valve 25 will be described below as a representative.
[0123]
7, 8 and 9 are flowcharts showing the control operation of the control means 3 of the positioning device 1 in focus adjustment. 8 and 9 show a subroutine in step S10a (two places) in FIG. Hereinafter, description will be given based on this flowchart.
[0124]
In the focus adjustment, first, the four illumination devices 71 to 74 are turned on (step S100).
[0125]
Next, the liquid crystal light valve 25 is actuated (driven), the predetermined pixel is turned on, and the above-mentioned focus adjustment projection image 131 shown in FIG. 43 is projected on the screen 2 (step S101).
[0126]
That is, in step S101, as shown in FIG. 1, the light emitted from the illumination devices 71 to 74 and transmitted through the turned-on pixels among the pixels of the liquid crystal light valve 25 is projected onto the projection region 100 on the screen 2. .
[0127]
Next, the liquid crystal light valve 25 is moved along the Z axis to the image data acquisition start position (rough reference position in the Z axis direction) along the Z axis by the triaxial table 8 (step S102). When the liquid crystal light valve 25 is positioned at a predetermined position in the Z-axis direction, the center of the effective screen area of the liquid crystal light valve 25 is positioned at the predetermined position.
[0128]
The image data acquisition start position is set in advance to a predetermined position (a position where the focus is not achieved) sufficiently separated from a position where the focus is expected to be achieved in a direction away from the dichroic prism 21.
[0129]
Next, camera no. 1 (camera 61), image data relating to the luminance of the imaging region 611 (hereinafter simply referred to as “image data”) is obtained and stored in the memory 4 (step S103).
[0130]
Next, camera no. 2 (camera 62), and the image data of the imaging area 621 is stored in the memory 4 (step S104).
[0131]
Next, camera no. 3 (camera 63), and the image data of the imaging area 631 is stored in the memory 4 (step S105).
[0132]
Next, camera no. 4 (camera 64), and the image data of the imaging area 641 is stored in the memory 4 (step S106).
[0133]
Next, a dispersion value acquisition process (subroutine shown in FIGS. 8 and 9) is executed (step S10a).
[0134]
In this distributed value acquisition process, the camera No. 1 to camera no. For each image (electronic image) captured in step 4, a variance value Vv of the Y-axis direction component (vertical component) and a variance value Vh of the X-axis direction component (lateral component) are acquired.
[0135]
In this case, as shown in FIG. Among the one imaging region 611 (all pixels of the camera No. 1), a predetermined region (for example, pixels of 240 rows × 240 columns of the camera No. 1) is a processing region 550 in the dispersion value acquisition process. It is set in advance.
[0136]
Similarly, camera no. 2-Camera No. Predetermined regions (for example, pixels of 240 rows × 240 columns) in the center of the four imaging regions 621 to 641 are preset as processing regions 550 in the variance value acquisition processing (not shown).
[0137]
As shown in FIG. 34, XY coordinates are assumed. The X-axis direction (horizontal direction) of this XY coordinate indicates the camera number. 1 corresponds to the row direction of the pixel No. 1 and the Y-axis direction (vertical direction) indicates the camera number. This corresponds to the column direction of one pixel.
[0138]
Similarly, camera no. 2-Camera No. 4 also assume XY coordinates (not shown).
[0139]
FIG. 35 is a diagram schematically showing a part of the processing area 550.
[0140]
As shown in the figure, a portion corresponding to the pixel of the liquid crystal light valve 25 in the processing region 550 is a pixel portion 551, and a portion corresponding to a portion other than the pixel of the liquid crystal light valve 25, that is, other than the pixel portion 551. The portion is a gap portion 552. The luminance of the pixel portion 551 is higher than the luminance of the gap portion 552.
[0141]
Of the gap portion 552, a portion corresponding to a portion between the pixels of the liquid crystal light valve 25 arranged in the Y-axis direction, that is, a portion between the pixel portions 551 arranged in the Y-axis direction is defined as a gap in the Y-axis direction. Part 553.
[0142]
Further, a portion of the gap portion 552 corresponding to a portion between the pixels of the liquid crystal light valve 25 arranged in the X-axis direction, that is, a portion between the pixel portions 551 arranged in the X-axis direction is defined as the X-axis. The direction gap portion 554 is used.
[0143]
Further, a portion of the gap portion 552 between the adjacent Y-axis direction gap portions 553 and also between the adjacent X-axis direction gap portions 554 is defined as a common gap portion 555.
[0144]
A portion composed of the pixel portions 551 arranged in the X-axis direction and the X-axis direction gap portions 554 between the pixel portions 551 arranged in the X-axis direction is defined as A row and arranged in the X-axis direction. A portion constituted by the Y-axis direction gap portion 553 and the common gap portion 555 between the Y-axis direction gap portions 553 arranged in the X-axis direction is defined as a B row.
[0145]
Further, a portion composed of the pixel portion 551 arranged in the Y-axis direction and the Y-axis direction gap portion 553 between the pixel portions 551 arranged in the Y-axis direction is defined as a C column, and is arranged in the Y-axis direction. A portion formed by the X-axis direction gap portion 554 and the common gap portion 555 between the X-axis direction gap portions 554 arranged in the Y-axis direction is defined as a D row.
[0146]
Here, in the present invention, when a predetermined pixel of the liquid crystal light valve 25 is turned off (a light beam is blocked) and an image of the pixel portion is not projected, the processing region 550 corresponds to the non-projected pixel. The portion is a portion corresponding to a portion other than the pixel of the liquid crystal light valve 25 (a portion other than the pixel portion 551), that is, a gap portion 552. In other words, in the present invention, the portion of the processing area 550 corresponding to the pixel of the liquid crystal light valve 25 (pixel portion 551) means the portion of the projected image of the pixel of the liquid crystal light valve 25.
[0147]
In this distributed value acquisition process, first, camera No. 1, the camera No. 1 in the processing area 550 is captured. The luminance in each pixel of 1 is integrated in the Y-axis direction (vertical direction), and the integrated value of the luminance in the Y-axis direction (vertical direction) is obtained (step S201). This integrated value is the camera No. in the processing area 550. As many pixels as 1 in the X-axis direction (lateral direction) are obtained.
[0148]
36 and 37 are diagrams showing a part of the processing area 550 and a graph of the integrated value of luminance in the Y-axis direction corresponding to the part. It should be noted that the vertical axis of the graph is the integrated value of luminance in the Y-axis direction, and the horizontal axis is the camera number corresponding to the integrated value. The position of one pixel column in the X-axis direction is taken.
[0149]
As shown in FIG. 36, the integrated value of luminance in the Y-axis direction is large in the C column including the pixel portion 551, and is small in the D column not including the pixel portion 551.
[0150]
Next, camera no. Of the columns of one pixel, 30 columns (30 columns) are selected from the one with the larger integrated value of luminance in the Y-axis direction (step S202).
[0151]
In this case, the camera No. Since one pixel column is selected from the larger integrated value, all the selected columns 560 belong to the C column as shown in FIG.
[0152]
In the present invention, the number of the selected columns 560 is not limited to 30 lines. That is, the camera No. belonging to the C column. 1 may be selected, or camera numbers belonging to column C may be selected. A part of one pixel column may be selected.
[0153]
Next, the pixel luminance variance (σ) for the selected 30-line column 560. ² ) Is obtained (step S203).
[0154]
In this step S203, the brightness value and the camera No. The number of pixels of 1 is detected, and based on these, the variance value is obtained.
[0155]
The magnitude of the dispersion value corresponds to the magnitude of the contrast between light and darkness (image sharpness) in the pixel portion 551 arranged in the Y-axis direction and the Y-axis direction gap portion 553. That is, the variance value is information for detecting the contrast between the A row and the B row. As will be described later, when the variance value is the maximum, the contrast between the pixel portions 551 arranged in the Y-axis direction and the Y-axis direction gap portion 553, that is, the contrast between the A row and the B row is maximized.
[0156]
Next, the dispersion value obtained in step S203 is set to the camera number. 1 is stored in the memory 4 as a dispersion value (dispersion value of the X-axis direction component) Vh having an X-axis direction component (lateral direction component) of the image taken in 1, and this dispersion value Vh and a dispersion value Vv described later are also stored. Correspondingly, the position (Z coordinate) in the Z-axis direction of the liquid crystal light valve 25 at this time is stored in the memory 4 (step S204).
[0157]
Next, camera no. 1, the camera No. 1 in the processing area 550 is captured. The luminance in each pixel of 1 is integrated in the X-axis direction (horizontal direction), and an integrated value of the luminance in the X-axis direction (horizontal direction) is obtained (step S205). This integrated value is the camera No. in the processing area 550. As many pixels as 1 in the Y-axis direction (vertical direction) are obtained.
[0158]
38 and 39 are diagrams showing a part of the processing region 550 and a graph of the integrated value of the luminance in the X-axis direction corresponding to the part. It should be noted that the horizontal axis of the graph is the integrated value of luminance in the X-axis direction, and the vertical axis is the camera No. corresponding to the integrated value. The position of one pixel row in the Y-axis direction is taken.
[0159]
As shown in FIG. 38, the integrated value of the luminance in the X-axis direction is large in the A row including the pixel portion 551, and is small in the B row not including the pixel portion 551.
[0160]
Next, camera no. Among the rows of one pixel, 30 rows (30 rows) are selected from the one with the larger integrated value of the luminance in the X-axis direction (step S206).
[0161]
In this case, the camera No. Since the row of one pixel is selected from the larger integrated value, as shown in FIG. 39, all the selected rows 570 belong to the A row.
[0162]
In the present invention, the number of the selected rows 570 is not limited to 30 lines. That is, the camera No. belonging to the A row. 1 may be selected, or camera numbers belonging to the A row may be selected. A part of the row of one pixel may be selected.
[0163]
Next, the variance value of the luminance of the pixel for the selected 30-line row 570 is obtained (step S207).
[0164]
In this step S207, the brightness value and the camera No. The number of pixels of 1 is detected, and based on these, the variance value is obtained.
[0165]
The magnitude of the dispersion value corresponds to the magnitude of the contrast of light and darkness (image sharpness) in the pixel portion 551 arranged in the X-axis direction and the gap portion 554 in the X-axis direction. That is, the variance value is information for detecting the contrast between the C column and the D column. As will be described later, when the variance value is maximum, the contrast between the pixel portions 551 arranged in the X-axis direction and the gap portion 554 in the X-axis direction, that is, the contrast between the C column and the D column is maximum.
[0166]
Next, the variance value obtained in step S207 is used as the camera number. 1 is stored in the memory 4 as a dispersion value (dispersion value of the Y-axis direction component) Vv having the Y-axis direction component (vertical direction component) of the image captured in 1 (step S208).
[0167]
Next, the camera No. As in the case of the image picked up in Step 1, the camera No. 2, the camera No. in the processing area 550 The luminance in each pixel of 2 is integrated in the Y-axis direction (vertical direction), and an integrated value of the luminance in the Y-axis direction (vertical direction) is obtained (step S209).
[0168]
Next, as described above, the camera No. Among the two pixel columns, 30 lines (30 columns) are selected from the one with the larger integrated value of luminance in the Y-axis direction (step S210).
[0169]
Next, in the same manner as described above, the variance value of the luminance of the pixel for the selected 30-line column 560 is obtained (step S211).
[0170]
Next, in the same manner as described above, the dispersion value obtained in step S211 is used as the camera number. 2 is stored in the memory 4 as a dispersion value (dispersion value of the X-axis direction component) Vh having an X-axis direction component (lateral direction component) of the image picked up in 2, and this dispersion value Vh and a dispersion value Vv described later Correspondingly, the position in the Z-axis direction (Z coordinate) of the liquid crystal light valve 25 at this time is stored in the memory 4 (step S212).
[0171]
Next, as described above, the camera No. 2, the camera No. in the processing area 550 2 is integrated in the X-axis direction (lateral direction) to obtain an integrated value of luminance in the X-axis direction (horizontal direction) (step S213).
[0172]
Next, as described above, the camera No. Of the two pixel rows, 30 rows (30 rows) are selected from the row with the larger integrated value of luminance in the X-axis direction (step S214).
[0173]
Next, in the same manner as described above, the variance value of the luminance of the pixel for the selected 30-line row 570 is obtained (step S215).
[0174]
Next, in the same manner as described above, the dispersion value obtained in the step S215 is used as the camera number. 2 is stored in the memory 4 as a dispersion value (dispersion value of the Y-axis direction component) Vv having the Y-axis direction component (vertical direction component) of the image captured in 2 (step S216).
[0175]
Next, the camera No. As in the case of the image picked up in Step 1, the camera No. For the image captured in step 3, the camera No. 3 is integrated in the Y-axis direction (vertical direction), and an integrated value of luminance in the Y-axis direction (vertical direction) is obtained (step S217).
[0176]
Next, as described above, the camera No. Of the three pixel columns, 30 lines (30 columns) are selected from the one with the larger integrated value of luminance in the Y-axis direction (step S218).
[0177]
Next, in the same manner as described above, the variance value of the luminance of the pixel for the selected 30-line column 560 is obtained (step S219).
[0178]
Next, in the same manner as described above, the dispersion value obtained in step S219 is used as the camera number. 3 is stored in the memory 4 as a dispersion value (dispersion value of the X-axis direction component) Vh having an X-axis direction component (lateral direction component) of the image taken in 3, and this dispersion value Vh and a dispersion value Vv to be described later Correspondingly, the position (Z coordinate) in the Z-axis direction of the liquid crystal light valve 25 at this time is stored in the memory 4 (step S220).
[0179]
Next, as described above, the camera No. For the image captured in step 3, the camera No. 3 is integrated in the X-axis direction (horizontal direction), and an integrated value of luminance in the X-axis direction (horizontal direction) is obtained (step S221).
[0180]
Next, as described above, the camera No. Among the three pixel rows, 30 rows (30 rows) are selected from the one with the larger integrated value of the luminance in the X-axis direction (step S222).
[0181]
Next, in the same manner as described above, the variance value of the luminance of the pixel for the selected 30-line row 570 is obtained (step S223).
[0182]
Next, in the same manner as described above, the dispersion value obtained in step S223 is used as the camera number. 3 is stored in the memory 4 as a dispersion value (dispersion value of the Y-axis direction component) Vv having the Y-axis direction component (vertical direction component) of the image captured in 3 (step S224).
[0183]
Next, the camera No. As in the case of the image picked up in Step 1, the camera No. 4, the camera No. in the processing area 550 The luminance in each pixel of 4 is integrated in the Y-axis direction (vertical direction), and the integrated value of the luminance in the Y-axis direction (vertical direction) is obtained (step S225).
[0184]
Next, as described above, the camera No. Of the four pixel columns, 30 lines (30 columns) are selected from the one with the larger integrated value of luminance in the Y-axis direction (step S226).
[0185]
Next, in the same manner as described above, the variance value of the luminance of the pixel for the selected column 560 of 30 lines is obtained (step S227).
[0186]
Next, in the same manner as described above, the variance value obtained in step S227 is used as the camera number. 4 is stored in the memory 4 as a dispersion value (dispersion value of the X-axis direction component) Vh having an X-axis direction component (lateral direction component) of the image captured in 4, and this dispersion value Vh and a dispersion value Vv described later Correspondingly, the position in the Z-axis direction (Z coordinate) of the liquid crystal light valve 25 at this time is stored in the memory 4 (step S228).
[0187]
Next, as described above, the camera No. 4, the camera No. in the processing area 550 The luminance in each pixel of 4 is integrated in the X-axis direction (horizontal direction), and the integrated value of the luminance in the X-axis direction (horizontal direction) is obtained (step S229).
[0188]
Next, as described above, the camera No. Of the four pixel rows, 30 rows (30 rows) are selected from the one with the larger integrated value of luminance in the X-axis direction (step S230).
[0189]
Next, in the same manner as described above, the variance value of the luminance of the pixel for the selected 30-line row 570 is obtained (step S231).
[0190]
Next, in the same manner as described above, the dispersion value obtained in the step S231 is used as the camera number. 4 is stored in the memory 4 as a dispersion value (dispersion value of the Y-axis direction component) Vv having the Y-axis direction component (vertical direction component) of the image captured in 4 (step S232).
[0191]
After step S232, the routine returns to the routine shown in FIG. 7, and as shown in FIG. 40, the liquid crystal light valve 25 is moved in the Z-axis direction by a certain amount (a certain distance) (for example, 50 μm) as shown in FIG. Step S107).
[0192]
As described above, since the image data acquisition start position in the coarse adjustment is set to a predetermined position farther from the dichroic prism 21 than the position where the focus is expected, in this step S107, the liquid crystal light valve 25 is set to the dichroic. It moves in the direction approaching the prism 21 (left side in FIG. 40).
[0193]
Further, since step S107 is the movement control of the liquid crystal light valve 25 for acquiring image data in the coarse adjustment, the moving amount (movement distance) is the liquid crystal for acquiring image data in the fine adjustment of step 117 described later. The amount of movement of the liquid crystal light valve 25 in the movement control of the light valve 25 is set to be larger.
[0194]
When the movement amount of the liquid crystal light valve 25 in step S107 is L1, and the movement amount of the liquid crystal light valve 25 in step S117 described later is L2, the ratio L1 / L2 is preferably about 2 to 10. About ~ 7 is more preferable.
[0195]
Further, the moving amount L1 of the liquid crystal light valve 25 in step S107 is preferably about 20 to 240 μm, and more preferably about 30 to 100 μm.
[0196]
Further, the moving amount L2 of the liquid crystal light valve 25 in step S117 described later is preferably about 3 to 30 μm, and more preferably about 5 to 20 μm.
[0197]
By setting the movement amounts L1 and L2 of the liquid crystal light valve 25 as described above, it is possible to improve the accuracy of focus adjustment while reducing the time required for focus adjustment.
[0198]
Next, it is determined whether or not the liquid crystal light valve 25 has reached the image data acquisition end position in the coarse adjustment (step S108).
[0199]
The image data acquisition end position is set in advance to a predetermined position (a position where the focus is not achieved) sufficiently separated from a position where the focus is expected to be achieved in a direction approaching the dichroic prism 21.
[0200]
If it is determined in step S108 that the liquid crystal light valve 25 has not reached the image data acquisition end position, the process returns to step S103, and steps S103 to S108 are executed again. As a result, the liquid crystal light valve 25 is moved L1 in the Z-axis direction from the previous position, and the camera No. 1 to camera no. For each of the images captured in step 4, the Y-axis direction component variance value Vv and the X-axis direction component variance value Vh can be acquired.
[0201]
If it is determined in step S108 that the liquid crystal light valve 25 has reached the image data acquisition end position, the focus in the Z-axis direction in the coarse adjustment is based on the dispersion value obtained in step S10a in the coarse adjustment. A position (Z coordinate) ZP, a movement amount (angle) Hd in the H direction, and a movement amount (angle) Vd in the V direction are obtained (step S109).
[0202]
In this step S109, the camera No. For the image captured in 1 (electronic image), the maximum value of the variance value Vv of the Y-axis direction component (longitudinal component) and the maximum value of the variance value Vh of the X-axis direction component (lateral component) are respectively obtained. From these, the position (Z coordinate) Z1v in the Z-axis direction of the liquid crystal light valve 25 when the image having the maximum variance value Vv of the Y-axis direction component is captured, and the image having the maximum variance value Vh of the X-axis direction component. The position (Z coordinate) Z1h in the Z-axis direction of the liquid crystal light valve 25 when the image is taken is detected.
[0203]
FIG. 2 is a graph showing the relationship between dispersion values Vh and Vv for the image captured in 1 and the position of the liquid crystal light valve 25 in the Z-axis direction when the dispersion values Vh and Vv are acquired. The vertical axis of the graph represents the dispersion values Vh and Vv, and the horizontal axis represents the position of the liquid crystal light valve 25 in the Z-axis direction.
[0204]
FIG. 42 is a diagram schematically showing an image (focus state: contrast) in the processing region 550 when the position of the liquid crystal light valve 25 in the Z-axis direction is changed.
[0205]
42, the position of the liquid crystal light valve 25 in the Z-axis direction is farthest from the dichroic prism 21 when the state of the image in the processing area 550 is (a). Hereinafter, (b), (c), ( It approaches the dichroic prism 21 in the order of d), (e), (f), and (g).
[0206]
The state shown in FIG. 42 (d) shows the target state of the image in the imaging area 611 in this focus adjustment, that is, the focused state (focused state). And B row contrast (contrast in the pixel portion 551 and Y-axis direction gap portion 553 arranged in the Y-axis direction), and C column and D-column contrast (pixel portion 551 arranged in the X-axis direction and X-axis direction) The contrast in the gap portion 554 is relatively high, and the balance is also good.
[0207]
As shown in FIG. 41, when the variance value Vh of the X-axis direction component is maximum, that is, when the liquid crystal light valve 25 is positioned at Z1h, the image in the processing area 550 is shown in FIG. The state, that is, the contrast between the A row and the B row (the contrast in the pixel portion 551 arranged in the Y-axis direction and the Y-axis direction gap portion 553) is the maximum state (first state).
[0208]
On the other hand, as shown in FIG. 41, when the variance value Vv of the Y-axis direction component is maximum, that is, when the liquid crystal light valve 25 is positioned at Z1v, the image in the processing area 550 is shown in FIG. ) State, that is, the contrast between the C column and the D column (contrast in the pixel portion 551 and the X-axis direction gap portion 554 arranged in the X-axis direction) is the maximum state (second state).
[0209]
The target state shown in FIG. 42 (d) is a predetermined state between the first state shown in FIG. 42 (c) and the second state shown in FIG. 42 (e). The state d) is obtained when the liquid crystal light valve 25 is located at a predetermined position (Z coordinate) between the position Z1v and the position Z1h.
[0210]
Accordingly, a predetermined position (Z coordinate) between the position Z1v and the position Z1h (for example, an intermediate position between Z1v and Z1h) is defined as Z1.
[0211]
In the present embodiment, for example, Z1v and Z1h are substituted into the following formula to obtain Z1.
[0212]
Z1 = a.Z1v + (1-a) .Z1h (where 0 <a <1)
The coefficient a in the above equation is set so that the image in the imaging area 611 projected on the screen 2 is in focus when the liquid crystal light valve 25 is positioned at Z1 obtained by the equation (the in-focus state is That is, the state of the image in the processing area 550 is set in advance so as to be the target state shown in FIG. The coefficient a is obtained experimentally prior to the setting, for example.
[0213]
Here, the camera No. in the processing area 550 is displayed. The image in the processing area 550 when the luminance dispersion value for all the pixels of 1 is maximized does not necessarily become the state shown in FIG. 42D due to, for example, the influence of lens aberration. Therefore, the camera No. in the processing area 550 If the position of the liquid crystal light valve 25 in the Z-axis direction when the luminance dispersion value for all the pixels of 1 is maximized is adjusted as described above as Z1, the focus adjustment is performed particularly when the lens aberration is large. Accuracy may be reduced.
[0214]
On the other hand, the position Z1h in the Z-axis direction of the liquid crystal light valve 25 when the dispersion value Vh of the X-axis direction component is maximum and the dispersion value Vv of the Y-axis direction component are maximum regardless of the magnitude of the lens aberration. When the liquid crystal light valve 25 is positioned at a predetermined position between the liquid crystal light valve 25 and the position Z1v in the Z-axis direction, the image in the processing area 550 has the focus shown in FIG. It will be in a consistent state.
[0215]
Therefore, as described above, the position Z1h in the Z-axis direction of the liquid crystal light valve 25 when the dispersion value Vh of the X-axis direction component is maximum, and the liquid crystal light valve 25 when the dispersion value Vv of the Y-axis direction component is maximum. The predetermined position between the Z-axis direction positions Z1v is Z1, and the adjustment described later is performed based on this Z1, so that the accuracy of focus adjustment can be increased.
[0216]
Similarly to the above, the camera No. 2, the maximum value of the variance value Vv of the Y-axis direction component (longitudinal component) and the maximum value of the variance value Vh of the X-axis direction component (lateral component) are respectively obtained for the image captured in 2 (electronic image). From these, the position (Z coordinate) Z2v in the Z-axis direction of the liquid crystal light valve 25 when the image having the maximum variance value Vv of the Y-axis direction component is captured, and the image having the maximum variance value Vh of the X-axis direction component. A position (Z coordinate) Z2h in the Z-axis direction of the liquid crystal light valve 25 at the time of imaging is detected, and a predetermined position (Z coordinate) between the position Z2v and position Z2h (for example, an intermediate position between Z2v and Z2h) ) Is Z2. In this embodiment, for example, Z2v and Z2h are substituted into the following formula to obtain Z2.
[0217]
Z2 = a.Z2v + (1-a) .Z2h (where 0 <a <1)
The coefficient a in the above formula is set in advance as described above.
[0218]
Similarly to the above, the camera No. 3, the maximum value of the variance value Vv of the Y-axis direction component (longitudinal component) and the maximum value of the variance value Vh of the X-axis direction component (lateral component) are respectively obtained for the image captured in 3 (electronic image). From these, the position (Z coordinate) Z3v in the Z-axis direction of the liquid crystal light valve 25 when the image having the maximum variance value Vv of the Y-axis direction component is captured, and the image having the maximum variance value Vh of the X-axis direction component. A position (Z coordinate) Z3h in the Z-axis direction of the liquid crystal light valve 25 at the time of imaging is detected, and a predetermined position (Z coordinate) between the position Z3v and the position Z3h (for example, an intermediate position between Z3v and Z3h) Is Z3. In this embodiment, for example, Z3v and Z3h are substituted into the following equation to obtain Z3.
[0219]
Z3 = a.Z3v + (1-a) .Z3h (where 0 <a <1)
The coefficient a in the above formula is set in advance as described above.
[0220]
Similarly to the above, the camera No. 4, the maximum value of the variance value Vv of the Y-axis direction component (longitudinal component) and the maximum value of the variance value Vh of the X-axis direction component (lateral component) are respectively obtained for the image captured in 4 (electronic image). From these, the position (Z coordinate) Z4v in the Z-axis direction of the liquid crystal light valve 25 when the image having the maximum variance value Vv of the Y-axis direction component is captured, and the image having the maximum variance value Vh of the X-axis direction component. A position (Z coordinate) Z4h in the Z-axis direction of the liquid crystal light valve 25 at the time of imaging is detected, and a predetermined position (Z coordinate) between the position Z4v and the position Z4h (for example, between Z4v and Z4h) ) Is Z4. In this embodiment, for example, Z4v and Z4h are substituted into the following equation to obtain Z4.
[0221]
Z4 = a.Z4v + (1-a) .Z4h (where 0 <a <1)
The coefficient a in the above formula is set in advance as described above.
[0222]
The focus position (Z coordinate) ZP of the liquid crystal light valve 25 in the Z-axis direction is obtained by substituting Z1, Z2, Z3 and Z4 into the following equation (1).
[0223]
[Expression 1]

[0224]
Here, camera no. The X coordinate when the center (center point) of one imaging area 611 is projected onto the liquid crystal light valve 25 with focus adjustment through the optical block 20 is the X1, Y coordinate in the above equation (1). Y1 in the formula.
[0225]
Similarly, camera no. When the center of the image pickup area 621 is projected onto the liquid crystal light valve 25 whose focus has been adjusted via the optical block 20, the X coordinate is X2 in the above equation (1), and the Y coordinate is Y2 in the above equation (1). And
[0226]
Similarly, camera no. 3 when the center of the image pickup area 631 is projected onto the liquid crystal light valve 25 whose focus has been adjusted via the optical block 20 is X3 in the equation (1), and Y3 is Y3 in the equation (1). And
[0227]
Similarly, camera no. The X coordinate when the center of the four imaging regions 641 is projected onto the liquid crystal light valve 25 whose focus is adjusted via the optical block 20 is X4 in the above equation (1), and the Y coordinate is Y4 in the above equation (1). And
[0228]
Note that X1, Y1, X2, Y2, X3, Y3, X4, and Y4 are determined at the corresponding camera positions.
[0229]
The movement amount (angle) Hd of the liquid crystal light valve 25 in the H direction is obtained by substituting the X1, X2, X3 and X4 and the Z1, Z2, Z3 and Z4 into the following equation (2). In addition, the direction of the arrow (H) in FIG. 5 is a positive direction.
[0230]
[Expression 2]

[0231]
Further, by substituting Hd, Y1, Y2, Y3 and Y4, and Z1, Z2, Z3 and Z4 into the following equation (3), the movement amount (angle) Vd of the liquid crystal light valve 25 in the V direction Ask for. In addition, the direction of the arrow (V) in FIG. 5 is a positive direction.
[0232]
[Equation 3]

[0233]
Next, the liquid crystal light valve 25 is rotated by the angle Hd obtained in step S109 in the H direction and by the angle Vd in the V direction by the triaxial table 8 (step S110).
[0234]
Here, when the liquid crystal light valve 25 is moved along the Z axis to the focus position ZP obtained in step S109 by the three-axis table 8, the processing area 550 of the four imaging areas 611 to 641 is included. Each of the image states approaches the target state shown in FIG. 42D (including the case where it matches the target state), that is, the four corners are roughly focused, but this operation is omitted ( The adjustment of the liquid crystal light valve 25 in the Z-axis direction may be performed only in the fine adjustment described later). Needless to say, this operation may be performed in the coarse adjustment.
[0235]
In step S110, the liquid crystal light valve 25 is moved by a predetermined amount in the X-axis direction and the Y-axis direction by the three-axis table 9 as necessary.
[0236]
In this step S110, the rough adjustment is completed.
[0237]
Next, a Z-axis direction moving range of the liquid crystal light valve 25 for obtaining image data in fine adjustment is set (step S111).
[0238]
In step S111, a position separated from the focus position ZP obtained in step S109 by a predetermined amount (predetermined distance) in a direction away from the dichroic prism 21 is an image data acquisition start position (Z A position that is separated from the focus position ZP by a predetermined amount (predetermined distance) in the direction approaching the dichroic prism 21 is set as an image data acquisition end position in fine adjustment in step S118 described later. .
[0239]
Each of the predetermined amounts is set in advance to, for example, a value that is ½ of the distance L3 in the Z-axis direction shown in FIG. 41 or a value that is larger than ½ of the distance L3. This predetermined amount is obtained experimentally, for example.
[0240]
The image data acquisition start position may be set so that the liquid crystal light valve 25 is not focused when the liquid crystal light valve 25 is positioned at the image data acquisition start position. Is located out of focus, and there is a difference between the luminance of the portion corresponding to the pixels of the liquid crystal light valve 25 in the imaging regions 611 to 641 and the luminance of the portion corresponding to the portion between the pixels. It is preferable to set so that
[0241]
The image data acquisition end position may be set so that the liquid crystal light valve 25 is not focused when the liquid crystal light valve 25 is positioned at the image data acquisition end position. Is located out of focus, and there is a difference between the luminance of the portion corresponding to the pixels of the liquid crystal light valve 25 in the imaging regions 611 to 641 and the luminance of the portion corresponding to the portion between the pixels. It is preferable to set so that
[0242]
Next, the liquid crystal light valve 25 is moved along the Z axis to the image data acquisition start position (Z axis direction setting position) in the fine adjustment by the triaxial table 8 (step S112).
[0243]
Next, camera no. 1 and the image data of the imaging area 611 is stored in the memory 4 (step S113).
[0244]
Next, camera no. 2 and the image data of the imaging area 621 is stored in the memory 4 (step S114).
[0245]
Next, camera no. 3 and the image data of the imaging area 631 is stored in the memory 4 (step S115).
[0246]
Next, camera no. 4 and the image data of the imaging area 641 is stored in the memory 4 (step S116).
[0247]
Next, as described above, the dispersion value acquisition process (the subroutine shown in FIGS. 8 and 9) is executed (step S10a). 1 to camera no. For each image (electronic image) captured in step 4, a variance value Vv of the Y-axis direction component (vertical component) and a variance value Vh of the X-axis direction component (lateral component) are acquired.
[0248]
Next, as shown in FIG. 40, the liquid crystal light valve 25 is moved in the Z-axis direction by a certain amount (for example, 10 μm) by the triaxial table 8 (step S117).
[0249]
As described above, the image data acquisition start position in the fine adjustment is set to a predetermined position farther from the dichroic prism 21 than the focus position ZP obtained in step S109. Therefore, in this step S117, the liquid crystal light valve 25 is set. Is moved in a direction approaching the dichroic prism 21 (left side in FIG. 40).
[0250]
Next, it is determined whether or not the liquid crystal light valve 25 has reached the image data acquisition end position in the fine adjustment (step S118).
[0251]
If it is determined in step S118 that the liquid crystal light valve 25 has not reached the image data acquisition end position, the process returns to step S113, and steps S113 to S118 are executed again. As a result, the liquid crystal light valve 25 is moved L1 in the Z-axis direction from the previous position, and the camera No. 1 to camera no. For each of the images captured in step 4, the Y-axis direction component variance value Vv and the X-axis direction component variance value Vh can be acquired.
[0252]
If it is determined in step S118 that the liquid crystal light valve 25 has reached the image data acquisition end position, the dispersion value acquired in step S10a in fine adjustment is set in the same manner as in the case of the coarse adjustment described above. Based on this, a focus position (focusing position) ZP in the Z-axis direction, a movement amount (angle) Hd in the H direction, and a movement amount (angle) Vd in the V direction in fine adjustment are obtained (step S119).
[0253]
Next, the liquid crystal light valve 25 is moved along the Z axis to the focus position ZP obtained in step S119 by the triaxial table 8, and rotated by the angle Hd in the H direction, and rotated by the angle Vd in the V direction. (Step S120).
[0254]
Thereby, in the case where the liquid crystal light valve 25 is moved along the Z axis to the focus position ZP obtained in step S109 in step S110, the image in the processing area 550 of the four imaging areas 611 to 641 is changed. Each state further approaches the target state shown in FIG. 42D (including the case where it matches the target state). That is, the four corners are substantially focused.
[0255]
In step S120, the liquid crystal light valve 25 is moved by a predetermined amount in the X-axis direction and the Y-axis direction by the triaxial table 9 as necessary.
[0256]
In step S120, the fine adjustment is finished, that is, the focus adjustment is finished.
[0257]
In the present invention, coarse adjustment and fine adjustment in focus adjustment may be performed by a method different from the method described above. As a method different from the method described above, for example, a method of performing focus adjustment by obtaining a dispersion value of the entire image, a method of performing focus adjustment by measuring contrast, and the like can be cited.
[0258]
However, one of the coarse adjustment and the fine adjustment in the focus adjustment, in particular, the fine adjustment is preferably performed by the method described above, and both the rough adjustment and the fine adjustment in the focus adjustment are more preferably performed by the method described above.
[0259]
In the embodiment, the number of adjustments in focus adjustment is set to two (rough adjustment and fine adjustment). However, in the present invention, the number of adjustments in focus adjustment is not limited to two, but one time. Or three or more times.
[0260]
However, the number of adjustments in the focus adjustment is preferably 2 times or more, and more preferably about 2 to 4 times.
[0261]
In the focus adjustment, if the adjustment is performed twice or more, the accuracy of the focus adjustment can be improved.
[0262]
Further, when the number of adjustments in the focus adjustment is two or more, the later adjustment, the interval of the position of the liquid crystal light valve 25 in the Z-axis direction at the time of imaging ( It is preferable to reduce the amount of movement when moving to the position at the time of imaging.
[0263]
Thereby, it is possible to improve the accuracy of the focus adjustment while shortening the time required for the focus adjustment.
[0264]
In the present invention, the moving direction of the liquid crystal light valve 25 when acquiring image data may be a direction away from the dichroic prism 21 (right side in FIG. 40). That is, the image data acquisition start position and the image data acquisition end position may be reversed from those in the above embodiment.
[0265]
In the present invention, the movement direction of the liquid crystal light valve 25 when acquiring image data may be different between the coarse adjustment and the fine adjustment.
[0266]
In the embodiment, when selecting the row 570 belonging to the A row and the column 560 belonging to the C column, a predetermined number of lines are selected from the larger integrated value. For example, a predetermined threshold value may be set, and a row or a column that is equal to or higher than the threshold value may be selected.
[0267]
However, it is preferable to select a predetermined number of lines from the larger integrated value as in the above embodiment. In this case, in particular, even if there is illumination unevenness or image unevenness, focus adjustment can be performed with high accuracy.
[0268]
After the focus adjustment is completed, the operation (drive) of the liquid crystal light valve 25 is maintained, the predetermined pixel is turned on, and the above-described position adjustment projection image 141 shown in FIG. 44 is projected on the screen 2 (step S150). .
[0269]
That is, in step S150, as shown in FIG. 1, the light emitted from the illumination devices 71 to 74 and transmitted through the turned-on pixels among the pixels of the liquid crystal light valve 25 is projected onto the projection area 110 on the screen 2. .
[0270]
After step S150, the process proceeds to position adjustment (alignment adjustment). Hereinafter, the position adjustment (alignment adjustment) of the liquid crystal light valve 25 for green will be described as a representative.
[0271]
10 and 13 to 18 are flowcharts showing the control operation of the control means 3 of the positioning device 1 in position adjustment (alignment adjustment). Hereinafter, description will be given based on this flowchart.
[0272]
In the following description of the alignment adjustment, moving the projection area 110 means moving the projection area 110 by moving the liquid crystal light valve 25 in the X-axis direction and the Y-axis direction by the three-axis table 9. . Further, rotating the projection area 110 means that the projection area 110 is rotated by rotating the liquid crystal light valve 25 in the W direction (around the Z axis) with the three-axis table 9.
[0273]
In the following description of alignment adjustment, the horizontal direction in FIGS. 19 to 25 corresponds to the X-axis direction of the liquid crystal light valve 25, and the vertical direction in FIGS. 19 to 25 corresponds to the Y-axis direction of the liquid crystal light valve 25. is doing.
[0274]
Before performing the following position adjustment, four patterns A1, B1, C1 corresponding to the portions including the corners 111a, 111b, 111c, and 111d of the projection area 110 as shown in FIG. And image data (luminance data) of D1 are stored. Furthermore, as shown in FIG. 12, a pattern H1 corresponding to a portion including the side 113a in the Y-axis direction on the left side in FIG. 6 of the projection area 110 and the X-axis direction on the lower side of the projection area 110 in FIG. The image data of the pattern V1 corresponding to the part including the side 114a is stored.
[0275]
Positions 121, 122, 123, and 124 are set in advance in the patterns A1, B1, C1, and D1, respectively. These positions 121, 122, 123, and 124 correspond to the positions of the edges (vertices) 112a, 112b, 112c, and 112d of the projection region 110, respectively. Further, positions 129a and 129b are preset in the patterns H1 and V1, respectively. These positions 129a and 129b are positioned so as to overlap with the corresponding sides 113a and 114a of the projection region 110.
[0276]
In addition, without storing these patterns in the memory 4 in advance, an external storage device (not shown) connected to the positioning device 1 (for example, a floppy disk, a hard disk, a magneto-optical disk, etc.) connected to the positioning device 1 as necessary in the following position adjustment. ) To the memory 4 as appropriate.
[0277]
Prior to describing the following position adjustment, pattern matching (pattern matching method) performed as appropriate during the following position adjustment will be described first.
[0278]
In pattern matching, for example, camera No. There are specific patterns (search patterns) such as patterns A1, B1, C1, D1, H1, and V1 in the image data (data to be searched) captured by 1, 2, 3, 4 and loaded into the memory 4 Search whether or not to do.
[0279]
If such a search pattern does not exist, it is determined that such a search pattern does not exist in the searched data.
[0280]
On the other hand, when such a search pattern exists, it is determined that such a search pattern exists in the searched data. At this time, the coordinates (X coordinate, Y coordinate) of the position (for example, positions 121 to 124, 129a, 129b, etc.) when the predetermined area in the captured image (data to be searched) matches the search pattern are obtained. obtain. If this coordinate (position) is not required in the subsequent processing, such a coordinate need not be obtained.
[0281]
Here, in the pattern matching, “the search pattern exists” does not mean that the pattern that completely matches the search pattern exists in the searched data, but the degree of matching with the search pattern (recognition rate) Means that there is a pattern having a value equal to or greater than a certain value (threshold).
[0282]
This value (threshold value) varies depending on various conditions such as the environment where the positioning device 1 is placed, but is preferably set to 80% or more, more preferably 90% or more. . If the threshold value is set to the above value, pattern matching can be performed with higher accuracy.
[0283]
In addition, when outputting or returning a result indicating that the search pattern exists in the searched data, the degree of coincidence may be returned or output as necessary.
[0284]
As shown in FIG. 10, in the position adjustment (alignment adjustment), first, rough adjustment is performed (S300), and then fine adjustment (S350) is performed.
[0285]
First, the rough adjustment in step S300 will be described.
[0286]
In the coarse adjustment in step S300, the first process (process S30A), the second process (process S30B), the third process (process S30C), the fourth process (process S30D), and the fifth process The processing (processing S30E), the sixth processing (processing S30F), the seventh processing (processing S30G), and the eighth processing (processing S30H) are performed. Hereinafter, each process is demonstrated in detail for every step based on FIGS. 13-16 and 19-24.
[0287]
[Process S30A] The first process includes steps S301 to S303 and a pattern C introduction process (process S90a).
[0288]
By executing Steps S301 to S303, it is possible to detect whether or not the corner 111c of the projection area 110 exists within the imaging area (target area) 631. Further, when the corner 111c does not exist in the imaging region 631, the corner 111c can be introduced into the imaging region 631 by executing the pattern C introduction process (processing S90a).
[0289]
[Step S301] First, camera no. 3 (camera 63), and the image data of the imaging region 631 is stored in the memory 4.
[0290]
[Step S302] Next, pattern matching is performed on the image data stored in the memory 4 in Step S301 using the pattern C1 as a search pattern.
[0291]
[Step S303] Next, as a result of pattern matching, when the pattern C1 exists in the image data stored in the memory 4 in Step S301, that is, as shown in FIG. If the part 111c exists, the second process (process S30B), that is, step S304 is performed, and if it does not exist, the pattern C introduction process (process S90a) is performed.
[0292]
Here, “the corner 111c does not exist in the imaging region 631” means that the result that the corner 111c does not exist is obtained by pattern matching. In the following description, the same can be said when the same determination as in this step is performed based on the result of pattern matching.
[0293]
[Processing S90a] The pattern C introduction process includes steps S901 to S910 as shown in FIG.
[0294]
By executing this pattern C introduction processing, the corner 111c can be placed in or close to the imaging region 631. Furthermore, by executing this process, the relative positional relationship between the projection area 110 and the imaging area 631 can be known.
[0295]
[Step S901] First, pattern matching is performed on the image data stored in the memory 4 in Step S301 using the pattern H1 as a search pattern.
[0296]
[Step S902] Next, as a result of pattern matching, when the pattern H1 is present in the image data stored in the memory 4 in Step S301, that is, as shown in FIG. When the side 113a of the area 110 in the Y-axis direction exists, step S903 is performed, and when it does not exist, step S904 is performed.
[0297]
[Step S903] Next, the projection area 110 is moved (displaced) upward in FIG. The amount of movement at this time is, for example, an amount corresponding to 1/3 of the length n of the imaging region 631 in the Y-axis direction.
[0298]
Accordingly, as shown in FIG. 19B2, the corner 111c of the projection area 110 enters the imaging area 631. Alternatively, for example, when the corner 111c of the projection area 110 is far from the imaging area 631, as in the case where the corner 111c exists at a position separated from the imaging area 631 by n / 3, the corner 111c of the projection area 110 is obtained. Approaches the imaging region 631.
[0299]
Then, it returns to step S301.
[0300]
In this step, the amount of movement of the projection region 110 can be set to an arbitrary value according to various conditions when adjusting the alignment. This can also be said when the same processing as this step is performed in the following steps (for example, step S906, step S909, step S910, etc.).
[0301]
[Step S904] Next, pattern matching is performed on the image data stored in the memory 4 in step S301 using the pattern V1 as a search pattern.
[0302]
[Step S905] Next, as a result of pattern matching, when the pattern V1 is present in the image data stored in the memory 4 in step S301, that is, as shown in FIG. 19 (A3), projection is performed within the imaging region 631. When the side 114a of the area 110 in the X-axis direction exists, step S906 is performed, and when it does not exist, step S907 is performed.
[0303]
[Step S906] Next, the projection area 110 is moved rightward in FIG. The amount of movement at this time is, for example, an amount corresponding to 1/3 of the length m of the imaging region 631 in the X-axis direction.
[0304]
Thereby, as shown in FIG. 19 (B3), the corner 111c of the projection area 110 enters the imaging area 631. Alternatively, for example, when the corner 111c of the projection area 110 is far from the imaging area 631, as in the case where the corner 111c exists at a position away from m / 3 from the imaging area 631, the corner 111c of the projection area 110 is obtained. Approaches the imaging region 631.
[0305]
Then, it returns to step S301.
[0306]
[Step S907] Next, for the image data stored in the memory 4 in Step S301, the brightness of the entire image data, that is, the brightness in the imaging region 631 is obtained.
[0307]
[Step S908] Next, as a result of obtaining the luminance, if the luminance is less than the threshold value (when the brightness in the imaging region 631 is less than the threshold value), that is, as shown in FIG. If none of the corner portion 111c and the sides 113a and 114a of the projection area 110 exists in 631, step S909 is executed. On the other hand, when the luminance is a certain value or more (when the brightness in the imaging region 631 is greater than or equal to the threshold value), that is, when the imaging region 631 is included in the projection region 110 as shown in FIG. Executes step S910.
[0308]
This threshold value is sufficiently higher than the luminance when none of the corners 111c and the sides 113a and 114a of the projection area 110 are present in the imaging area 631, and the imaging area 631 is included in the projection area 110. The brightness is set to be sufficiently lower than the brightness in the case where it is set.
[0309]
[Step S909] Next, the projection area 110 is moved in the lower left direction in FIG. At this time, the amount of movement in the downward direction in FIG. 20 is, for example, an amount corresponding to 1/3 of the length n in the Y-axis direction of the imaging region 631, and the amount of movement in the left direction in FIG. This is an amount corresponding to 1/3 of the length m of the imaging region 631 in the X-axis direction.
[0310]
Thereby, as shown in FIG. 20 (B4), the corner 111c of the projection area 110 enters the imaging area 631. Alternatively, when the corner 111 c of the projection area 110 is separated from the imaging area 631 by a distance corresponding to the movement amount, the corner 111 c of the projection area 110 approaches the imaging area 631.
[0311]
Then, it returns to step S301.
[0312]
[Step S910] Next, the projection area 110 is moved in the upper right direction in FIG. At this time, the movement amount in the upward direction in FIG. 20 is, for example, an amount corresponding to 1/3 of the length n in the Y-axis direction of the imaging region 631, and the movement amount in the right direction in FIG. This is an amount corresponding to 1/3 of the length m of the imaging region 631 in the X-axis direction.
[0313]
Thereby, as shown in FIG. 20 (B5), the corner 111c of the projection area 110 enters the imaging area 631. Alternatively, when the corner 111 c of the projection area 110 is separated from the imaging area 631 by a distance corresponding to the movement amount, the corner 111 c of the projection area 110 approaches the imaging area 631.
[0314]
Then, it returns to step S301.
[0315]
Even when the corner 111c cannot be placed in the imaging region 631 by one pattern C introduction process, as in the case where the corner 111c is greatly separated from the imaging region 631, the pattern C introduction processing is performed as 1 Since the corner 111c can be brought closer to the imaging region 631 each time the execution is performed, the corner 111c can be finally placed in the imaging region 631 by executing the pattern C introduction process a plurality of times.
[0316]
[Process S30B] The second process includes steps S304 and S305.
[0317]
By executing the second process, the corner 111c can be matched with the center 125c of the imaging region 631.
[0318]
[Step S304] First, the X-axis direction of the projection area 110 for moving the edge 112c of the projection area 110 to the center 125c of the imaging area 631 based on the position 123 obtained by the last pattern matching in step S302. And the amount of movement in the Y-axis direction is obtained.
[0319]
As described above, the coordinates of the obtained position 123 correspond to the coordinates of the edge 112c, that is, the coordinates of the position 123 represent the coordinates of the edge 112c. The amount of movement of the projection area 110 can be obtained from the coordinates with the center 125c.
[0320]
[Step S305] Next, the projection area 110 is moved based on the movement amounts of the projection area 110 in the X-axis direction and the Y-axis direction obtained in step S304.
[0321]
Accordingly, as shown in FIG. 19B1, the corner 111c of the projection area 110 matches the center 125c of the imaging area 631.
[0322]
In the third to fifth processes (processes S30C to S30E) described below, alignment is performed based on the imaging area 611 and the imaging area 631. That is, the alignment is performed by placing a weight on the Y-axis direction of the projection region 110, in other words, the Y-axis direction of the liquid crystal light valve 25.
[0323]
[Process S30C] The third process includes steps S306 to S310 and a pattern A introduction process (process S90b).
[0324]
By executing the first process and the second process, the corner 111c of the projection area 110 can be introduced into the imaging area 631, and the corner 111c can be matched with the center 125c of the imaging area 631. .
[0325]
However, even after performing such processing, as shown in FIG. 21A6, when the side 113a is largely inclined with respect to the line connecting the center 125c of the imaging region 631 and the center 125a of the imaging region 611. In some cases, the corner 111a is not within the imaging region 611.
[0326]
Even in such a case, the corner 111a can be introduced into the imaging region 611 by executing the third process.
[0327]
Prior to executing the following step S308, 0 is substituted in advance for the variable I necessary for calculating the amount of movement of the projection region 110 in step S921 described later.
[0328]
[Step S306] First, camera no. 3 (camera 63), and the image data of the imaging region 631 is stored in the memory 4.
[0329]
[Step S307] Next, pattern matching is performed on the image data stored in the memory 4 in step S306 using the pattern C1 as a search pattern.
[0330]
[Step S308] Next, camera no. 1 (camera 61), and the image data of the imaging area 611 is stored in the memory 4.
[0331]
[Step S309] Next, pattern matching is performed on the image data stored in the memory 4 in Step S308 using the pattern A1 as a search pattern.
[0332]
[Step S310] Next, as a result of pattern matching, when the pattern A1 does not exist in the image data stored in the memory 4 in Step S308, that is, as shown in FIG. If the part 111a does not exist, the pattern A introduction process (process S90b) is executed. On the other hand, if the pattern A1 exists, the fourth process (process S30D), that is, step S311 is executed.
[0333]
[Process S90b] The pattern A introduction process includes steps S921 and S922.
[0334]
The corner 111a can be introduced into the imaging region 611 by executing this pattern A introduction process a predetermined number of times.
[0335]
[Step S921] First, the position (coordinates) of the destination edge 112c when moving the projection area 110 in the next step S922 is obtained. This can be obtained, for example, by the following equation. This expression gives the coordinates of the edge 112c corresponding to the value of I. As described above, n is the length of the imaging region 631 in the Y-axis direction, and m is the length of the imaging region 631 in the X-axis direction.
[0336]
X-axis position = IDOU_X1 + (I mod 3) * (m)
(Here, (I mod 3) means finding the remainder when I is divided by 3)
Position in the Y-axis direction = IDOU_Y1 + (I / 3) * (n / 2) (Note that the obtained movement amount is rounded down)
Here, the constants IDOU_X1 and IDOU_Y1 correspond to the coordinates of the movement destination of the edge 112c in the next step S922 when I = 0.
[0337]
These constants IDOU_X1 and IDOU_Y1 are preferably values such that the position of the edge 112c after movement when I = 0 is located at the upper left in FIG. 21 with respect to the center 125c of the imaging region 631. Thereby, the edge 112a can be efficiently introduced into the imaging region 611.
[0338]
[Step S922] Next, the projection area 110 is moved so that the edge 112c comes to the position of the movement destination of the edge 112c obtained in step S921.
[0339]
Thereby, as shown in FIGS. 21B61 to B64 and FIGS. 22B65 to B69, the edge 112a enters the imaging region 611 when I becomes a predetermined value.
[0340]
In FIG. 21, (B61) shows the position of the projection area 110 when I = 0, (B62) shows the position of the projection area 110 when I = 1, and (B63) shows the projection when I = 2. The position of the area 110, (B64) is the position of the projection area 110 when I = 3, (B65) in FIG. 22 is the position of the projection area 110 when I = 4, and (B66) is I = 5. (B67) is the position of the projection area 110 when I = 6, (B68) is the position of the projection area 110 when I = 7, and (B69) is I = The position of the projection area 110 at 8 is shown.
[0341]
In the example illustrated in FIGS. 21 and 22, the edge 112 a enters the imaging region 611 when I = 8.
[0342]
Thereafter, the process returns to step S308. At that time, 1 is added to I.
[0343]
Thus, the edge 112a can be placed in the imaging region 611 by executing the pattern A introduction process (process S90b) a predetermined number of times while changing the value of I.
[0344]
In step S921, the position in the X-axis direction and the position in the Y-axis direction of the edge 112c are obtained from the same variable I. However, variables corresponding to the X-axis and the Y-axis are prepared, respectively. The position in the axial direction and the position in the Y-axis direction may be obtained independently from these prepared variables.
[0345]
In step S921, the position in the X-axis direction and the position in the Y-axis direction of the edge 112c are obtained by calculation. However, the position or movement amount in the X-axis direction and the Y-axis direction corresponding to the value I is determined in advance. Alternatively, it may be prepared as a table, and the projection area 110 may be moved in step S922 based on the table.
[0346]
[Process S30D] The fourth process includes steps S311 and S312.
[0347]
By executing the fourth process, the straight line 126 (target line) connecting the center 125a of the imaging region 611 and the center 125c of the imaging region 631 and the side 113 can be made parallel. That is, the inclination of the side 113 can be eliminated.
[0348]
[Step S311] First, in the pattern A introduction process (process S90b), the coordinates (position) of the edge 112c obtained last in step S921 and the coordinates of the edge 112a obtained by the last pattern matching in step S309 are as follows. Based on the above, the inclination θ1 between the straight line 126 and the side 113a as shown in FIG.
[0349]
If the pattern A introduction process (process S90b) has never been performed, the position 123 obtained by the pattern matching in step S307 becomes the position of the edge 112c.
[0350]
[Step S312] Next, the projection area 110 is rotated based on θ1 obtained in Step S311.
[0351]
Thereby, as shown in FIG. 23 (B71), the straight line 126 and the side 113a can be made parallel.
[0352]
[Process S30E] The fifth process includes Steps S313 to S317.
[0353]
By executing the fifth process, the edges 112a and 112c approach the target position. In addition, the number of pixels in the projection area 110 that falls within the imaging area 611 and the number of pixels in the projection area 110 that fall within the imaging area 631 can be made substantially equal.
[0354]
[Step S313] First, camera no. 3 (camera 63), and the image data of the imaging region 631 is stored in the memory 4.
[0355]
[Step S314] Next, pattern matching is performed on the image data stored in the memory 4 in step S313 using the pattern C1 as a search pattern.
[0356]
[Step S315] Next, the camera No. 1 (camera 61), and the image data of the imaging area 611 is stored in the memory 4.
[0357]
[Step S316] Next, pattern matching is performed on the image data stored in the memory 4 in Step S315 using the pattern A1 as a search pattern.
[0358]
[Step S317] Next, based on the positions of the edge 112a and the edge 112c obtained by the pattern matching in the steps S314 and S316, the straight line 126 and the side 113a are matched and y1 = y2. Next, the projection area 110 is moved.
[0359]
Note that y1 is the width between the upper side 612 of the imaging region 611 in FIG. 23 and the upper side 114b of the projection region 110 in FIG. 23, as shown in FIG. 23 (B72). Further, y2 is a width between the lower side 632 in FIG. 23 of the imaging region 631 and the lower side 114a of the projection region 110 in FIG.
[0360]
Thereby, as shown in FIG. 23 (B72), the edges 112a and 112c approach the target position. Further, the number of pixels of the projection area 110 that falls within the imaging area 611 and the number of pixels of the projection area 110 that fall within the imaging area 631 substantially coincide.
[0361]
The sixth to eighth processes described below are processes similar to the third to fifth processes.
[0362]
In the third to fifth processes, alignment is performed with reference to the imaging region 611 and the imaging region 631. In other words, alignment was performed with weight placed in the Y-axis direction (side 113a) of the projection region 110, in other words, in the Y-axis direction of the liquid crystal light valve 25. On the other hand, in the following sixth to eighth processes, alignment is performed based on the imaging region 631 and the imaging region 641. In other words, alignment is performed with weight placed in the X-axis direction (side 114a) of the projection region 110, in other words, in the X-axis direction of the liquid crystal light valve 25.
[0363]
[Process S30F] The sixth process includes steps S318 to S322 and a pattern D introduction process (process S90c).
[0364]
By executing the third to fifth processes, the corner 111a of the projection area 110 can be introduced into the imaging area 611, the side 113a can be parallel to the straight line 126, and the edge 112a 112c can be brought close to the target position.
[0365]
However, even after such processing is performed, as shown in FIG. 23A8, there is a very small possibility that the corner 111d is not within the imaging region 641.
[0366]
Even in such a case, the corner 111d can be introduced into the imaging region 641 by executing the sixth process.
[0367]
Prior to executing the following step S320, 0 is substituted in advance for the variable I necessary for calculating the amount of movement of the projection region 110 in step S931 described later.
[0368]
[Step S318] First, camera no. 3 (camera 63), and the image data of the imaging region 631 is stored in the memory 4.
[0369]
[Step S319] Next, pattern matching is performed on the image data stored in the memory 4 in step S318 using the pattern C1 as a search pattern.
[0370]
[Step S320] Next, the camera No. 4 (camera 64), and the image data of the imaging area 641 is stored in the memory 4.
[0371]
[Step S321] Next, pattern matching is performed on the image data stored in the memory 4 in Step S320 using the pattern D1 as a search pattern.
[0372]
[Step S322] Next, as a result of pattern matching, if the pattern D1 does not exist in the image data stored in the memory 4 in Step S320, that is, as shown in FIG. If the part 111d does not exist, the pattern D introduction process (process S90c) is executed. On the other hand, if the pattern D1 exists, the seventh process (process S30G), that is, step S323 is executed.
[0373]
[Processing S90c] The pattern D introduction process includes steps S931 and S932.
[0374]
By executing the pattern D introduction process a predetermined number of times, the corner 111d can be introduced into the imaging region 641.
[0375]
[Step S931] First, the position (coordinates) of the destination edge 112c when moving the projection region 110 in the next step S932 is obtained. This can be obtained, for example, by the following equation. This expression gives the coordinates of the edge 112c corresponding to the value of I. As described above, n is the length of the imaging region 631 in the Y-axis direction, and m is the length of the imaging region 631 in the X-axis direction.
[0376]
X-axis position = IDOU_X2 + (I mod 3) * (m)
(Here, (I mod 3) means finding the remainder when I is divided by 3)
Position in the Y-axis direction = IDOU_Y2 + (I / 3) * (n / 3) (Note that the obtained moving amount is rounded down)
Here, the constants IDOU_X2 and IDOU_Y2 correspond to the coordinates of the movement destination of the edge 112c in the next step S932 when I = 0.
[0377]
These constants IDOU_X2 and IDOU_Y2 are preferably values such that the position of the edge 112c after movement when I = 0 is located at the upper left in FIG. 23 rather than the center 125c of the projection region 631. Thereby, the edge 112d can be efficiently introduced into the imaging region 641.
[0378]
[Step S932] Next, the projection area 110 is moved so that the edge 112c comes to the position of the movement destination of the edge 112c obtained in step S931. Note that the process of moving in the Y-axis direction can be omitted (it may be moved only in the X-axis direction).
[0379]
As a result, the edge 112d enters the imaging region 641 when I reaches a predetermined value.
[0380]
Thereafter, the process returns to step S320. At that time, 1 is added to I.
[0381]
As described above, by executing the pattern D introduction process (process S90c) a predetermined number of times while changing the value of I, the edge 112d can be placed in the imaging region 641.
[0382]
In step S931, the position in the X-axis direction and the position in the Y-axis direction of the edge 112c are obtained from the same variable I. However, variables corresponding to the X-axis and the Y-axis are prepared, respectively. The position in the axial direction and the position in the Y-axis direction may be obtained independently from these prepared variables.
[0383]
In step S931, the position of the edge 112c in the X-axis direction and the position in the Y-axis direction are obtained by calculation. Alternatively, it may be prepared as a table, and the projection area 110 may be moved in step 932 based on the table.
[0384]
[Process S30G] The seventh process includes steps S323 and S324.
[0385]
By executing the seventh process, the straight line 127 (target line) connecting the center 125c of the imaging region 631 and the center 125d of the imaging region 641 and the side 114a can be made parallel. That is, the inclination of the side 114a can be eliminated.
[0386]
[Step S323] First, in the pattern D introduction process (process S90c), the coordinates (position) of the edge 112c finally obtained in step S931 and the coordinates of the edge 112d obtained in the last pattern matching in step S321 are as follows. Based on the above, the inclination θ2 between the straight line 127 and the side 114a as shown in FIG.
[0387]
If the pattern D introduction process (process S90c) has never been performed, the position 123 obtained by the pattern matching in step S319 becomes the position of the edge 112c.
[0388]
[Step S324] Next, the projection area 110 is rotated based on θ2 obtained in step S323.
[0389]
Thereby, as shown in FIG. 24 (B91), the straight line 127 and the side 114a can be made parallel.
[0390]
[Process S30H] The eighth process includes steps S325 to S329.
[0390]
By executing the eighth process, the edges 112c and 112d approach the target position. In addition, the number of pixels in the projection area 110 that falls within the imaging area 631 and the number of pixels in the projection area 110 that fall within the imaging area 641 can be made substantially equal.
[0392]
[Step S325] First, camera no. 3 (camera 63), and the image data of the imaging region 631 is stored in the memory 4.
[0393]
[Step S326] Next, pattern matching is performed on the image data stored in the memory 4 in Step S325 using the pattern C1 as a search pattern.
[0394]
[Step S327] Next, the camera No. 4 (camera 64), and the image data of the imaging area 641 is stored in the memory 4.
[0395]
[Step S328] Next, pattern matching is performed on the image data stored in the memory 4 in Step S327 using the pattern D1 as a search pattern.
[0396]
[Step S329] Next, based on the positions of the edge 112c and the edge 112d obtained by the pattern matching in the steps S314 and S316, the straight line 127 and the side 114a are matched and x1 = x2. Next, the projection area 110 is moved.
[0397]
Note that x1 is the width between the left side 633 in FIG. 24 of the imaging region 631 and the left side 113a in FIG. 24 of the projection region 110, as shown in FIG. 24 (B92). Further, x2 is the width between the right side 643 of the imaging region 641 in FIG. 24 and the right side 113b of the projection region 110 in FIG.
[0398]
Thereby, as shown in FIG. 24 (B92), the edges 112c and 112d approach the target position. Further, the number of pixels of the projection area 110 that falls within the imaging area 631 and the number of pixels of the projection area 110 that fall within the imaging area 641 substantially coincide.
[0399]
Thus, the rough adjustment is completed.
[0400]
Hereinafter, the first embodiment of the fine adjustment (position adjustment process) in step S350 will be described.
[0401]
By performing the fine adjustment in the following step S350, the alignment can be adjusted with very high accuracy. Furthermore, even when the projection region 110 is not completely rectangular as shown in FIG. 25 (A13), alignment adjustment can be performed accurately.
[0402]
Prior to explaining the fine adjustment in step S350, the four vertex position measurement process (process S90d) that is appropriately performed during the fine adjustment in step S350 will be described first.
[0403]
[Processing S90d] As shown in FIG. 18, the four-vertex position measurement processing includes steps S941 to S948.
[0404]
By executing the four-vertex position measurement process, the coordinates of the edge 112a, the edge 112b, the edge 112c, and the edge 112d can be obtained.
[0405]
[Step S941] First, camera no. 1 (camera 61), and the image data of the imaging area 611 is stored in the memory 4.
[0406]
[Step S942] Next, pattern matching is performed on the image data stored in the memory 4 in Step S941 using the pattern A1 as a search pattern.
[0407]
[Step S943] Next, camera no. 2 (camera 62), and the image data of the imaging area 621 is stored in the memory 4.
[0408]
[Step S944] Next, pattern matching is performed on the image data stored in the memory 4 in step S943 using the pattern B1 as a search pattern.
[0409]
[Step S945] Next, the camera No. 3 (camera 63), and the image data of the imaging region 631 is stored in the memory 4.
[0410]
[Step S946] Next, pattern matching is performed on the image data stored in the memory 4 in step S945 using the pattern C1 as a search pattern.
[0411]
[Step S947] Next, camera no. 4 (camera 64), and the image data of the imaging area 641 is stored in the memory 4.
[0412]
[Step S948] Next, pattern matching is performed on the image data stored in the memory 4 in step S947 using the pattern D1 as a search pattern.
[0413]
Note that the coordinates of the edge 112a obtained by the above four vertex position measurement process (process S90d) are (gluxg, gluyg), the coordinates of the edge 112b are (gruxg, gruyg), the coordinates of the edge 112c are (gldxg, gldyg), The coordinates of the edge 112d are set to (grdxg, grdyg) (see FIG. 25 (A10)).
[0414]
In the fine adjustment in step S350, a first process (process S35A), a second process (process S35B), and a third process (process S35C) are performed. Hereinafter, each process will be described in detail for each step based on FIGS.
[0415]
[Processing S35A] The first processing includes four vertex position measurement processing (Processing S90d) and Steps S351 to S353.
[0416]
By executing the first process, the inclination of the entire projection area 110, that is, the inclination of the entire liquid crystal light valve 25 is minimized.
[0417]
[Process S90d] First, the above-described four vertex position measurement process is executed.
[0418]
[Step S351] Next, θgux, θgdx, θgly, and θgry are obtained based on the coordinates of the edges 112a to 112d obtained by the four vertex position measurement processing.
[0419]
As illustrated in FIG. 25A11, θgux is an angle between the side 114b and a line connecting the center 125a of the imaging region 611 and the center 125b of the imaging region 621. θgdx is an angle between the side 114a and a line connecting the center 125c of the imaging region 631 and the center 125d of the imaging region 641. θgly is an angle between the side 113a and a line connecting the center 125a of the imaging region 611 and the center 125c of the imaging region 631. θgry is an angle between the side 113b and a line connecting the center 125b of the imaging region 621 and the center 125d of the imaging region 641.
[0420]
These θgux, θgdx, θgly, and θgry are the coordinates (gluxg, gluyg), (gruxg, gldyg), (gldxg, gldyg), and (grdxg,) of the edges 112a to 112d obtained in the four-vertex position measurement process (processing S90d). grdyg) and the coordinates of the centers 125a to 125d.
[0421]
[Step S352] Next, based on θgux, θgdx, θgly, and θgry obtained in step S351, a rotation angle θ for rotating the projection region 110 in the next step S353 is obtained.
[0422]
This can be obtained from the following equation. Note that θk is a preset reference angle.
[0423]
θgx = (θgux + θgdx) / 2
θgy = (θgly + θgry) / 2
θg = (θgx + θgy) / 2
θ = θk-θg
[Step S353] Next, the projection area 110 is rotated by the rotation angle θ degrees obtained in step S352.
[0424]
Thereby, as shown in FIG. 25 (B12), the inclination of the projection area 110 in the X-axis direction and the y-axis direction is minimized.
[0425]
[Process S35B] The second process includes a four-vertex position measurement process (Process S90d) and Steps S354 to S356.
[0426]
By executing this second process, the position of the center of the projection area 110 matches the preset reference coordinates. That is, the center position of the projection area 110 can be adjusted by executing the second process.
[0427]
[Process S90d] First, the above-described four vertex position measurement process is executed.
[0428]
[Step S354] Next, center coordinates (gxg, gyg) of the projection region 110 are obtained based on the coordinates of the edges 112a to 112d obtained by the four vertex position measurement processing.
[0429]
The coordinates are obtained from, for example, the coordinates (gluxg, gluyg), (gruxg, gryg), (gldxg, gldyg), (grdxg, grdyg) of the edges 112a to 112d obtained in the four-vertex position measurement process (process S90d). The coordinates of the midpoints of the sides 113a, 113b, 114a, and 114b are obtained, and the straight line connecting the midpoint of the side 113a and the midpoint of the side 113b, the midpoint of the side 114a, and the side 114b are obtained from the coordinates of these midpoints. It can be obtained by obtaining the coordinates of the intersection point with the straight line connecting the middle point.
[0430]
That is, the coordinates of the intersection of the straight line connecting the midpoint of the side 113a and the midpoint of the side 113b and the straight line connecting the midpoint of the side 114a and the midpoint of the side 114b are the center coordinates (gxg, gyg).
[0431]
[Step S355] Next, based on the center coordinates (gxg, gyg) of the projection area 110 obtained in step S354, the movement amount when moving the projection area 110 in the next step S356 is obtained.
[0432]
This can be obtained from the following equation. Note that kxg and kyg are preset reference coordinates.
[0433]
X-axis movement amount = kxg-gxg
Y-axis movement amount = kyg-gyg
[Step S356] Next, the projection area 110 is moved based on the X-axis movement amount and the Y-axis movement amount obtained in Step S355.
[0434]
As a result, the center of the imaging region 110 moves to the reference coordinates.
[0435]
[Process S35C] The third process includes a four-vertex position measurement process (Process S90d) and Steps S357 to S359.
[0436]
By executing the third process, the entire liquid crystal light valve 25 can be adjusted to a position where the deviation in the X-axis direction and the Y-axis direction is minimized.
[0437]
[Process S90d] First, the above-described four vertex position measurement process is executed.
[0438]
[Step S357] Next, with respect to the coordinates of the edges 112a to 112d obtained by the four-vertex position measurement process, deviations from reference coordinates (target positions) set in advance for the respective edges 112a to 112d are obtained.
[0439]
Here, the reference coordinates of the edge 112a are (kluxg, kluyg), the reference coordinates of the edge 112b are (kruxg, kruyg), the reference coordinates of the edge 112c are (klddxg, kldyg), and the reference coordinates of the edge 112d are (krdxg, krdyg). And
[0440]
Here, assuming that the deviations of the edges 112a to 112d from the reference coordinates in the X-axis direction are X1 to X4 and the deviations of the edges 112a to 112d from the reference coordinates in the Y-axis direction are Y1 to Y4, respectively, X1 to X4 and Y1. -Y4 can be represented by the following formula, for example.
[0441]
X1 = kluxg-gluxg
X2 = gruxg-kruxg
X3 = kldxg-gldxg
X4 = grdxg-krdxg
Y1 = kluyg-gluyg
Y2 = kruyg-gruyg
Y3 = gldyg-kldyg
Y4 = grdyg-krdyg
[Step S358] Next, based on X1 to X4 and Y1 to Y4 obtained in Step S357, the amount of movement for moving the projection region 110 in the next Step S359 is obtained.
[0442]
The amount of movement in the X-axis direction is obtained by taking the average of X1 to X4 having the first largest absolute value and the second largest absolute value. When the absolute value of the largest value and the second largest value have the same sign, the average of the first absolute value and the third largest absolute value among X1 to X4 is taken. Thus, the amount of movement in the X-axis direction is obtained. Furthermore, when the absolute value of the largest value and the third largest value have the same sign, the average of the first absolute value and the fourth largest absolute value among X1 to X4 is calculated. As a result, the amount of movement in the X-axis direction is obtained.
[0443]
The amount of movement in the Y-axis direction is obtained by taking the average of Y1 to Y4 having the first largest absolute value and the second largest absolute value. When the absolute value of the largest value and the second largest value have the same sign, the average of the first absolute value and the third largest absolute value among Y1 to Y4 is taken. Thus, the amount of movement in the Y-axis direction is obtained. Furthermore, when the absolute value of the largest value and the third largest value have the same sign, the average of the first absolute value and the fourth largest absolute value among Y1 to Y4 is calculated. As a result, the amount of movement in the Y-axis direction is obtained.
[0444]
[Step S359] Next, the projection region 110 is moved based on the amount of movement in the X-axis direction and the amount of movement in the Y-axis direction obtained in Step S358.
[0445]
As a result, of the edges 112a to 112d (corner portions 111a to 111d), the edge (corner portion) farthest from the reference coordinates corresponding to these approaches the reference coordinates.
[0446]
Therefore, for example, as shown in FIG. 25 (A13), the position can be accurately adjusted even when the projection region 110 is not completely rectangular.
[0447]
This completes the fine adjustment (position adjustment processing) in step S350 of the first embodiment.
[0448]
In this fine adjustment, the four vertex position measurement process (process S90d) is performed for each of the first process (process S35A), the second process (process S35B), and the third process (process S35C). However, the four-vertex position measurement process (process S90d) may not be performed for each process. However, it is preferable to execute the four vertex position measurement process (process S90d) for each process as in the first embodiment. Thereby, the precision of alignment adjustment improves more.
[0449]
In this fine adjustment, the four vertex position measurement process (process S90d) is performed, the coordinates of the edges 112a to 112d are obtained, and the first to third processes (process S35A to process S35C) are performed. At least two coordinates among the coordinates 112a to 112d are obtained, and the first process (process S35A), the second process (process S35B), and the third process (process S35C) are performed based on the coordinates. Also good.
[0450]
In the alignment adjustment, the image projected on the screen 2 (projected image), that is, the projected image of the pixel of the light valve is deformed (for example, fog, unevenness, blur, blurring) due to the characteristics of the optical system (lens aberration). Etc.) may occur.
[0451]
In such a case, for example, when pattern matching is performed using patterns A1 to D1 as shown in FIG. 11 as a search pattern, it may be difficult to perform the search accurately.
[0452]
At this time, pattern matching may be performed using patterns A2, B2, C2, and D2 as search patterns as shown in FIG. Each of these patterns A2, B2, C2, and D2 includes portions corresponding to corner portions 111a, 111b, 111c, and 111d when the projected image of the liquid crystal light valve pixel has a deformation of the projected image due to lens aberration. It corresponds to.
[0453]
Furthermore, first, pattern matching is performed using the patterns A1 to D1 as shown in FIG. 11 as search patterns, and when there is no search pattern in the search target data by such pattern matching, as shown in FIG. Pattern matching may be performed again using the patterns A2 to D2 as search patterns.
[0454]
As described above, by setting a plurality of predetermined patterns (patterns corresponding to one corner) used for pattern matching, it is possible to easily cope with a case where the degree of deformation of the projected image due to lens aberration is different. And the alignment accuracy can be improved.
[0455]
In this case, as shown in FIG. 26, in the patterns A2 to D2, positions 121, 122, 123, and 124 are, for example, edges 112a, 112b, and 112c when there is no deformation of the projected image due to lens aberration in each pixel. And 112d.
[0456]
Similarly to the above, for the pattern H1 and the pattern V1 as shown in FIG. 12, a pattern H2 and a pattern V2 corresponding to the pattern H1 and the pattern V1 as shown in FIG. Matching can be performed.
[0457]
The pattern H2 and the pattern V2 correspond to portions including the corresponding sides 113a and 114a when the projected image of the pixel of the liquid crystal light valve has deformation of the projected image due to lens aberration.
[0458]
In this case, as shown in FIG. 27, in patterns H2 and V2, positions 129a and 129b overlap with sides 113a and 114a when, for example, each pixel has no deformation of the projected image due to lens aberration. Position.
[0459]
Hereinafter, a second embodiment of fine adjustment (position adjustment processing) in step S350 will be described.
[0460]
In fine adjustment, the camera No. 1, Camera No. 2, Camera No. 3 and camera no. 4, each image data of the imaging areas 611, 621, 631 and 641 is stored in the memory 4.
[0461]
Next, the camera No. 1, Camera No. 2, Camera No. 3 and camera no. Each image data of the image imaged in 4 is read out, and each specific position 128 shown in FIG. 28A is detected by edge processing (edge processing method) (the X coordinate and Y coordinate of the specific position 128 are obtained). . This edge processing will be described in detail later.
[0462]
Then, as shown in FIG. 28 (b), the liquid crystal light valve 25 is displaced by the three-axis table 9 so that each specific position 128 is closer to the corresponding target position (including the case where they coincide). That is, the liquid crystal light valve 25 is rotated in the W direction and moved in the X-axis direction and the Y-axis direction so that each specific position 128 is closer to the corresponding target position (including a case where they coincide with each other).
[0463]
Next, edge processing will be described. Typically, camera no. The case where the Y coordinate of the specific position of the image imaged by 4 is calculated | required is demonstrated.
[0464]
FIG. 29 is a flowchart showing the control operation of the control means 3 of the positioning device 1 in edge processing. Hereinafter, description will be given based on this flowchart.
[0465]
In the edge processing, first, camera No. 4 (in this embodiment, pixels: 400 rows × 600 columns), and image data of the imaging region 641 is stored in the memory 4 (step S401).
[0466]
The camera No. For example, the image captured at 4, that is, the image stored in the memory 4 is as shown in FIG. 30.
[0467]
As shown in FIG. 30, XY coordinates are assumed. The XY coordinates correspond to the surface of the electronic image. That is, the camera No. The column (first column to 600th column) and row (first row to 400th row) of each pixel of the four pixels are respectively coordinated in the X-axis direction (X coordinate) and Y-axis direction (Y). Corresponds to the coordinate). In this embodiment, the camera No. The coordinates of the pixels in the 4th j-th row (j-th row) and i-th column (i-th column) are (i, j).
[0468]
Next, the luminance in each pixel is integrated in the Y-axis direction, and an integrated value Iy [i] = Σf (i, j) of luminance in the Y-axis direction is obtained (step S402).
[0469]
A graph of the integrated value Iy [i] is shown in FIG. The vertical axis of the graph is the integrated value Iy [i], and the horizontal axis is the X coordinate i of the pixel.
[0470]
Next, a maximum value Iymax and a minimum value Iymin of the integrated value Iy [i] are obtained (step S403).
[0471]
Next, a threshold value Ty is set (step S404).
[0472]
In step S404, the threshold value Ty is obtained by substituting the maximum value Iymax and the minimum value Iymin obtained in step S403 into the following equation.
[0473]
Ty = (Iymax−Iymin) * α + Iymin (where 0 <α <1)
Next, as shown in FIG. 30, the X coordinate Xc of the cross point between the threshold value Ty and the integrated value Iy [i] is obtained (step S405).
[0474]
Next, as shown in FIG. 31, a rectangular area surrounded by four points of coordinates (0, 0), coordinates (Xc, 0), coordinates (Xc, 400), and coordinates (0, 400) is set (step S406).
[0475]
Next, in the set area, the luminance in each pixel is integrated in the X-axis direction, and an integrated value Iax [j] = Σf (i, j) of the luminance in the X-axis direction is obtained (step S407).
[0476]
A graph of the integrated value Iax [j] (first waveform) is shown in FIG. The horizontal axis of the graph is the integrated value Iax [j], and the vertical axis is the Y coordinate j of the pixel. This integrated value Iax [j] is a first waveform that indicates the change in the Y-axis direction of the integrated value of luminance in the X-axis direction.
[0477]
Next, a maximum value Iaxmax and a minimum value Iaxmin of the integrated value Iax [j] are obtained (step S408).
[0478]
Next, a threshold value Tax is set (step S409).
[0479]
In step S409, the threshold value Tax is obtained by substituting the maximum value Iaxmax and the minimum value Iaxmin obtained in step S408 into the following equations.
[0480]
Tax = (Iaxmax−Iaxmin) * α + Iaxmin (where 0 <α <1)
Next, as shown in FIG. 31, the Y coordinate Yac of the cross point between the threshold value Tax and the integrated value Iax [j] is obtained (step S410).
[0481]
Next, as shown in FIG. 31, the Y coordinate Ppy [P] at each peak (positive peak) and the Y coordinate Pmy [q] at each bottom (negative peak) of the graph of the integrated value Iax [j] are obtained. (Step S411).
[0482]
In the case of FIG. 31, the number of positive peaks is 4 and the number of negative peaks is 3. Therefore, the Y coordinates Ppy [1], Ppy [2], Ppy [3] and Ppy at the four positive peaks are used. [4] and Y coordinates Pmy [1], Pmy [2] and Pmy [3] at the three negative peaks are detected, respectively.
[0483]
Next, an average value Ppyavr of the intervals in the vertical axis direction of adjacent positive peaks is obtained from the following equation (step S412).
[0484]
Ppyavr = {Σ (Ppy [p + 1] −Ppy [p])} / (n−1)
(Where n is the number of positive peaks)
Next, as shown in FIG. 31, the Y coordinate Pmpymax at the negative peak where Yac−1.2 * Ppyavr−Pmy [q] is minimum within the range where the Y coordinate is less than Yac−1.2 * Ppyavr is detected. (Step S413).
[0485]
In other words, Pmpymax is Pmy [q] which is smaller than Yac-1.2 * Ppyavr and closest to Yac-1.2 * Ppyavr.
[0486]
Next, the difference value Diax [j] of the integrated value Iax [j] is calculated from the following equation (step S414).
[0487]
Diax [j] = Iax [j + 1] −Iax [j−1]
In other words, the difference value Diax [j] on the j-th row is a value obtained by subtracting the integrated value Iax [j−1] on the j−1-th row from the integrated value Iax [j + 1] on the j + 1-th row.
[0488]
FIG. 32 shows a graph of the difference value Diax [j] and a graph of the integrated value Iax [j]. In the graph of the difference value Diax [j], the horizontal axis represents the difference value Diax [j], and the vertical axis represents the Y coordinate j of the pixel.
[0489]
Next, as shown in FIG. 32, near Pmpymax (indicated by a circle in FIG. 32), a zero cross point (Y coordinate when Diax [j] = 0) is calculated using Diax [j] (zero cross processing is performed). ), And the obtained zero cross point is set as the Y coordinate of the specific position (step S415).
[0490]
That is, in step S415, the camera No. 4, the Y coordinate of the specific position of the image captured is obtained.
[0491]
This completes the edge processing.
[0492]
The camera No. In order to obtain the X coordinate of the specific position of the image captured in step 4, the above-described edge processing for obtaining the Y coordinate of the specific position may be performed in the same manner by changing x to y and y to x.
[0493]
In this case, in the set area, the relationship between the integrated value of the luminance in the Y axis direction obtained by integrating the luminance in each pixel in the Y axis direction and the X coordinate of the pixel (the X axis of the integrated value of the luminance in the Y axis direction). The waveform in the graph (not shown) showing the change in the direction is the second waveform, and the X coordinate of the specific position is obtained based on the second waveform in the same manner as the edge processing for obtaining the Y coordinate of the specific position described above. .
[0494]
FIG. 33 is a diagram illustrating the first waveform and the second waveform.
[0495]
As shown in the figure, in the second embodiment, the positions of the peak and bottom of the first waveform in the fourth Y-axis direction from the lower side in FIG. 33 (the end side of the imaged projection area). Is the Y coordinate of the specific position 128, and the fourth waveform peak and bottom positions in the X-axis direction of the second waveform from the right side in FIG. It is a coordinate.
[0496]
In addition, camera No. 1, Camera No. 2 and camera no. In order to obtain the X coordinate and Y coordinate of the specific position of each image captured in step 3, the above-described process may be performed.
[0497]
This completes the fine adjustment (position adjustment processing) in step S350 of the second embodiment.
[0498]
As can be seen from the edge processing flowchart as described above, in the fine adjustment in step S350 of the second embodiment, the position of the peak or bottom of the first waveform shown in FIG. Preferably, the Y coordinate of the specific position is used, and the peak or bottom position of the second waveform in the X axis direction is the X coordinate of the specific position.
[0499]
Also, the Ny-th position in the Y-axis direction of the peak and bottom of the first waveform (point where the first derivative is 0) is specified from the lower side in FIG. 33 (the end side of the imaged projection area). As the Y coordinate of the position, from the right side in FIG. 33 (the end side of the imaged projection area), the peak and bottom of the second waveform (points where the first derivative is 0) in the Nx-th X-axis direction The position is preferably the X coordinate of the specific position.
[0500]
In this case, Ny and Nx may be different but are preferably equal. By making Ny and Nx equal, the accuracy of position adjustment can be further increased.
[0501]
Ny and Nx are each preferably an even number. That is, it is preferable that the position of the bottom of the first waveform in the Y-axis direction is the Y coordinate of the specific position, and the position of the bottom of the second waveform in the X-axis direction is the X coordinate of the specific position. preferable.
[0502]
When Ny and Nx are even numbers, the Y coordinate and X coordinate of the specific position can be obtained more accurately, thereby improving the accuracy of position adjustment.
[0503]
Ny and Nx are each preferably 2 or more, more preferably 4 or more, and still more preferably about 4-8.
[0504]
When Ny and Nx are 2 or more, the Y coordinate and X coordinate of the specific position can be obtained more accurately, thereby improving the accuracy of position adjustment.
[0505]
Thus, the positioning of the green liquid crystal light valve 25 is completed, and as described above, the liquid crystal light valve 25 is temporarily fixed to the optical block 20 and then permanently fixed.
[0506]
Next, the red liquid crystal light valve 24 and the blue liquid crystal light valve 26 are positioned in the same manner as described above.
[0507]
At this time, when the fine adjustment (position adjustment process) in step S350 is performed in the fine adjustment of the first embodiment, the green liquid crystal light valve 25 and the red liquid crystal are performed as follows. The red liquid crystal light valve 24 and the blue liquid crystal light valve 26 can be positioned so that the images formed by the light valve 24 and the blue liquid crystal light valve 26 overlap each other.
[0508]
First, prior to positioning the liquid crystal light valve 24 for red and the liquid crystal light valve 26 for blue, the four apex position measurement process (process S90d) is performed, and the projection region 110 of the liquid crystal light valve 25 for green is displayed. The coordinates of the edges 112a to 112d are obtained.
[0509]
Based on these coordinates, θk used in step S352, kxg and kyg used in step S355, and edges 112a to 112a used in step S357 in positioning the liquid crystal light valve 24 for red and the liquid crystal light valve 26 for blue. The reference coordinates (kluxg, kluyg), (kruxg, kruyg), (kldxg, kldyg), and (krdxg, krdyg) of 112d are obtained.
[0510]
Based on these values, the red liquid crystal light valve 24 and the blue liquid crystal light valve 26 are positioned.
[0511]
Accordingly, the red liquid crystal light valve 24 and the blue liquid crystal light valve 24, the red liquid crystal light valve 24, and the blue liquid crystal light valve 26 are overlapped with each other so that the images formed by the green liquid crystal light valve 24 and the blue liquid crystal light valve 26 overlap each other. The liquid crystal light valve 26 can be positioned.
[0512]
On the other hand, when the fine adjustment (position adjustment processing) in step S350 is performed by the fine adjustment of the second embodiment, the green liquid crystal light valve 25 and the red liquid crystal light are performed as follows. The red liquid crystal light valve 24 and the blue liquid crystal light valve 26 can be positioned so that the images formed by the bulb 24 and the blue liquid crystal light valve 26 overlap each other.
[0513]
First, prior to positioning the red liquid crystal light valve 24 and the blue liquid crystal light valve 26, the projection areas 110 of the green liquid crystal light valve 25 are respectively imaged by the cameras 61 to 64, and each image data is captured. Store in memory 4.
[0514]
Then, each image data is read from the memory 4, and the X coordinate and Y coordinate of each specific position are obtained by the edge processing described above. The obtained X coordinate and Y coordinate of each specific position are set as the X coordinate and Y coordinate of each target position in fine adjustment of position adjustment, respectively.
[0515]
Accordingly, the red liquid crystal light valve 24 and the blue liquid crystal light valve 24, the red liquid crystal light valve 24, and the blue liquid crystal light valve 26 are overlapped with each other so that the images formed by the green liquid crystal light valve 24 and the blue liquid crystal light valve 26 overlap each other. The liquid crystal light valve 26 can be positioned.
[0516]
When the positioning of the liquid crystal light valve 24 is completed, as described above, the liquid crystal light valve 24 is temporarily fixed to the optical block 20, and is then permanently fixed.
[0517]
Similarly, when the positioning of the liquid crystal light valve 26 is completed, as described above, the liquid crystal light valve 26 is temporarily fixed to the optical block 20 and then permanently fixed.
[0518]
As described above, according to the light valve positioning method of the present invention, each of the liquid crystal light valves 24 to 26 is automatically positioned, so that it is easier, faster and more reliable than the case where it is manually performed. Can be positioned.
[0519]
In addition, positioning can be performed with higher accuracy than when positioning is performed manually.
[0520]
In particular, since the projection area 100 for focus adjustment and the projection area 110 for position adjustment are set and positioning is performed, the cameras 61 to 64 can also be used for focus adjustment and position adjustment.
[0521]
For this reason, the number of cameras can be reduced as compared with the case where positioning is performed using a camera dedicated to focus adjustment and a camera dedicated to position adjustment, whereby the structure of the positioning device 1 can be simplified. In addition, the cost can be reduced.
[0522]
Compared to the case where positioning is performed using a camera dedicated to focus adjustment and a camera dedicated to position adjustment, the positioning device 1 is assembled, particularly when the cameras 61 to 64 are installed (assembled). It can be done easily.
[0523]
In addition, the projection area 100 for focus adjustment and the projection area 110 for position adjustment are set, and these are switched to perform focus adjustment and position adjustment. can do.
[0524]
In focus adjustment, coarse adjustment and fine adjustment are performed, so that the focus adjustment can be performed with high accuracy in a short time.
[0525]
Further, the position in the Z-axis direction of the liquid crystal light valves 24 to 26 when the dispersion value Vh of the X-axis direction component is maximum, and the Z of the liquid crystal light valves 24 to 26 when the dispersion value Vv of the Y-axis direction component is maximum. The position in the axial direction is obtained, and based on these, the positions in the Z-axis direction of the liquid crystal light valves 24 to 26 in the focused state shown in FIG. 42 (d) are obtained. Regardless, the accuracy of focus adjustment can be increased.
[0526]
In addition, the imaging area 611 of the camera 61, the imaging area 621 of the camera 62, the imaging area 631 of the camera 63, and the imaging area 641 of the camera 64 are respectively near the corner 101a of the projection area 100, as shown in FIG. It is located near the portion 101b, near the corner portion 101c, and near the corner portion 101d, and approaches or coincides with the focused state shown in FIG. Thus, the focus is adjusted over almost the entire projection area 100 on the screen 2. That is, high contrast is obtained in almost the entire projection area 100.
[0527]
In the position adjustment, coarse adjustment and fine adjustment are performed, so that the position adjustment can be performed with high accuracy in a short time.
[0528]
In addition, the imaging area 611 of the camera 61, the imaging area 621 of the camera 62, the imaging area 631 of the camera 63, and the imaging area 641 of the camera 64 are respectively shown in FIG. 111b, corner portion 111c, and corner portion 111d are included, and the position is adjusted with respect to all these corner portions, so that the position can be accurately adjusted.
[0529]
Further, by performing rough adjustment, even when the image projected on the screen does not exist in the target area, the corner of the image can be introduced into the target area, and the position can be adjusted efficiently. . Thereby, even when the projection area is located away from the target area, the position adjustment can be easily performed.
[0530]
Further, when performing the fine adjustment of the first embodiment, the position can be accurately adjusted even when the image projected on the screen is not completely rectangular.
[0531]
Further, in the fine adjustment of the position adjustment, when performing the fine adjustment of the second embodiment, the X coordinate and the Y coordinate of the specific position are obtained by the above-described edge processing using the integrated luminance value. The X coordinate and Y coordinate of the specific position can be obtained accurately, and thereby the accuracy of position adjustment can be further improved.
[0532]
According to the display unit and the projection display device of the present invention, the liquid crystal light valves 24, 25, and 26 are accurately positioned by the positioning method described above, so that the contrast (the sharpness of the image) is obtained over the entire area of the image. And a color image having no color shift (pixel shift) can be projected on the screen.
[0533]
Next, another embodiment of the light valve positioning method of the present invention will be described. In addition, description is abbreviate | omitted about a common point with the Example mentioned above, and a main difference is demonstrated.
[0534]
In the embodiment described above, the focus adjustment and position adjustment of the liquid crystal light valves 24 to 26 are performed by operating the liquid crystal light valves 24 to 26, respectively. In this embodiment, the focus adjustment of the liquid crystal light valves 24 to 26 is performed respectively. The light valves 24 to 26 are operated without being operated, and the position adjustment of the liquid crystal light valves 24 to 26 is performed by operating the liquid crystal light valves 24 to 26, respectively.
[0535]
Specifically, in this embodiment, step S101 in the flowchart shown in FIG. 7 is omitted from the above-described embodiment.
[0536]
When the liquid crystal light valves 24 to 26 are not operated, the light emitted to the liquid crystal light valves 24 to 26 passes through the pixels and is projected on the screen 2.
[0537]
Therefore, in this embodiment, for example, an area on the screen 2 corresponding to the effective screen area of the liquid crystal light valve 25 is set as the focus adjustment projection area 100 described above.
[0538]
In this case, when the four illumination devices 71 to 74 are turned on in step S100 of FIG. 7, a projected image 131 for focus adjustment (strictly speaking, illumination light is applied to the projection area 100 on the screen 2). The irradiated part) is projected.
[0539]
On the other hand, the position adjustment projection area 110 is set in the same manner as in the above-described embodiment.
[0540]
This positioning method can provide the same effects as those of the above-described embodiment.
[0541]
The light valve positioning method, display unit, and projection display device of the present invention have been described above based on the illustrated embodiment, but the present invention is not limited to this.
[0542]
For example, in the present invention, the structure of the positioning device to be used is not limited to the illustrated one.
[0543]
In the present invention, the shape of the first projection region and the shape of the second projection region are not limited to squares, but may be polygons such as triangles and pentagons.
[0544]
In the present invention, the position of the predetermined area imaged in the focus adjustment and the position of the predetermined area imaged in the position adjustment are not limited to the above embodiments.
[0545]
In the present invention, the number of cameras, that is, the number of predetermined areas imaged in the focus adjustment and the number of predetermined areas imaged in the position adjustment are not limited to the above embodiments.
[0546]
For example, the predetermined area imaged in the focus adjustment and the position adjustment may be three or less, and may be five or more.
[0547]
However, the predetermined area to be imaged in the focus adjustment and the position adjustment is preferably 3 or more (except when all of them are on the same straight line), and preferably 4 or 5 places (all of which are on the same straight line). Are preferred).
[0548]
By setting three or more predetermined areas to be imaged in focus adjustment and position adjustment, the Z axis direction of the light valve when the focus is in almost the entire area of the first projection area projected on the screen And the current position and posture of the light valve in the Z-axis direction can be detected. Thereby, the focus adjustment can be performed so that the focus is achieved in almost the entire area of the first projection area (high contrast is obtained in the almost entire area of the first projection area).
[0549]
FIGS. 51 and 52 show an example in which three predetermined areas to be imaged in focus adjustment and position adjustment are set, and implementation in the case where four predetermined areas to be imaged in focus adjustment and position adjustment are set. An example is shown in FIG.
[0550]
As shown in FIG. 51, in this embodiment, three cameras (not shown) are installed, and the imaging areas 411, 412 and 413 of these cameras are respectively inside the projection area 100 and the projection area. 110 is set so as to include the boundary 16 with the non-projection region 115.
[0551]
Specifically, the imaging region 411 is set in the vicinity of the side 104a and in the middle of the side 103a and the side 103b and includes an intermediate part of the side 114a.
[0552]
In addition, the imaging region 412 is located near the corner 101a and is set to include the corner 111a.
[0553]
The imaging region 413 is located near the corner 101b and is set to include the corner 111b.
[0554]
In this case, the Y coordinate of the specific position in the imaging area 411 is obtained from the image data of the imaging area 411, and the X coordinate and Y of the specific position in the imaging area 412 are obtained from the image data of the imaging area 412. The coordinates are obtained, and the X coordinate and the Y coordinate of a specific position in the imaging area 413 are obtained from the image data of the imaging area 413.
[0555]
Accordingly, the position is adjusted by displacing the liquid crystal light valve based on these pieces of information.
[0556]
As shown in FIG. 52, in this embodiment, three cameras (not shown) are installed, and the imaging areas 421, 422, and 423 of these cameras are respectively inside the projection area 100 and the projection area. 110 is set so as to include the boundary 16 with the non-projection region 115.
[0557]
Specifically, the imaging region 421 is set to be in the vicinity of the side 104b, in the middle of the side 103a and the side 103b, and to include an intermediate part of the side 114b.
[0558]
In addition, the imaging region 422 is located near the corner portion 101c and is set to include the corner portion 111c.
[0559]
In addition, the imaging region 423 is located near the corner 101d and is set to include the corner 111d.
[0560]
In this case, the Y coordinate of the specific position in the imaging area 421 is obtained from the image data of the imaging area 421, and the X coordinate and Y of the specific position in the imaging area 422 are obtained from the image data of the imaging area 422. The coordinates are obtained, and the X coordinate and the Y coordinate of the specific position in the imaging area 423 are obtained from the image data of the imaging area 423.
[0561]
Accordingly, the position is adjusted by displacing the liquid crystal light valve based on these pieces of information.
[0562]
As shown in FIG. 53, in this embodiment, four cameras (not shown) are installed, and the imaging areas 431, 432, and 433 of these cameras are respectively inside the projection area 100 and the projection area. 110 is set so as to include the boundary 16 with the non-projection region 115.
[0563]
Specifically, the imaging region 431 is set in the vicinity of the corner portion 101a and includes a portion of the side 114b near the corner portion 111a.
[0564]
The imaging region 432 is located near the corner portion 101b and is set to include a portion of the side 114b near the corner portion 111b.
[0565]
In addition, the imaging region 433 is located near the corner 101c and is set to include the corner 111c.
[0566]
The imaging region 434 is set near the corner 101d and includes the corner 111d.
[0567]
In this case, the Y coordinate of the specific position in the imaging area 431 is obtained from the image data of the imaging area 431, and the Y coordinate of the specific position in the imaging area 432 is obtained from the image data of the imaging area 432. The X and Y coordinates of a specific position in the imaging area 433 are obtained from the image data of the imaging area 433, and the X and Y coordinates of the specific position in the imaging area 434 are obtained from the image data of the imaging area 434. Is obtained.
[0568]
Accordingly, the position is adjusted by displacing the liquid crystal light valve based on these pieces of information.
[0569]
In addition, for example, the imaging region may be set in the vicinity of the side 103a and in the middle of the side 104a and the side 104b so as to include an intermediate part of the side 113a. In this case, the X coordinate of a specific position in the imaging area is obtained from the image data of the imaging area.
[0570]
Further, for example, the imaging region may be set in the vicinity of the side 103b and in the middle of the side 104a and the side 104b so as to include an intermediate part of the side 113b. In this case, the X coordinate of a specific position in the imaging area is obtained from the image data of the imaging area.
[0571]
In the embodiment, the first focus adjustment (coarse focus adjustment), the second focus adjustment (fine focus adjustment), the first position adjustment (position coarse adjustment), and the second position adjustment (position The light valves are positioned in the order of fine adjustment), but the present invention is not limited to this order. For example, the first focus adjustment (coarse adjustment of focus), the first position adjustment (position adjustment) The light valve may be positioned in the order of coarse adjustment), second focus adjustment (focus fine adjustment), and second position adjustment (position fine adjustment).
[0572]
In the embodiment, the light valve is configured by a liquid crystal light valve. However, the present invention is not limited to this, and may be configured by a light valve using, for example, a DMD (Digital Micromirror Device). . In the case of a light valve using a DMD, a predetermined pattern (bright / dark pattern) is formed by the DMD, and the pattern is projected onto a screen for positioning.
[0573]
In the fine adjustment in step S350 of the first embodiment, in the four-vertex position measurement process (process S90d), edge processing is performed to detect a specific position, and based on the specific position detected in the edge process, The first process (process S35A), the second process (process S35B), and the third process (process S35C) may be performed.
[0574]
【The invention's effect】
As described above, according to the light valve positioning method of the present invention, positioning can be performed easily, quickly, reliably and accurately.
[0575]
In particular, since positioning is performed using a common (same) camera for focus adjustment and position adjustment, the number of cameras is smaller than when positioning is performed using a camera dedicated to focus adjustment and a camera dedicated to position adjustment. The structure of the positioning device can be simplified.
[0576]
In addition, as compared with the case where positioning is performed using a camera dedicated to focus adjustment and a camera dedicated to position adjustment, assembly of the positioning device, particularly positioning of the camera when the camera is installed can be easily performed.
[0577]
In addition, since the first projection area and the second projection area are set, and these are switched to perform the focus adjustment and the position adjustment, the versatility is wide and the apparatus can be easily adapted to many models.
[0578]
In addition, since the focus adjustment is performed with coarse adjustment and fine adjustment, the focus adjustment can be performed with high accuracy in a short time. In the position adjustment, the coarse adjustment and fine adjustment are performed with a short time. Position adjustment can be performed with high accuracy.
[0579]
According to the display unit and the projection display device of the present invention, since the three light valves corresponding to red, green and blue are accurately positioned, a color image with high contrast and no color shift is displayed on the screen. Can be projected.
[Brief description of the drawings]
FIG. 1 is a side view schematically showing a configuration example of a positioning device used in a light valve positioning method of the present invention.
2 is a block diagram showing a circuit configuration of the positioning device shown in FIG. 1. FIG.
FIG. 3 is a cross-sectional view showing an optical head part (each liquid crystal light valve and a part of an optical system) of the projection display device according to the present invention.
FIG. 4 is an exploded perspective view showing a dichroic prism, a liquid crystal light valve corresponding to green, and a support member according to the present invention.
5 is a view schematically showing a liquid crystal light valve held by a chuck of the positioning device shown in FIG.
FIG. 6 is a diagram schematically showing projection areas on a screen by a liquid crystal light valve and an imaging area of each camera according to the present invention.
FIG. 7 is a flowchart showing the control operation of the control means of the positioning device at the time of focus adjustment in the present invention.
FIG. 8 is a flowchart showing the control operation of the control means of the positioning device at the time of focus adjustment in the present invention.
FIG. 9 is a flowchart showing a control operation of the control means of the positioning device at the time of focus adjustment in the present invention.
FIG. 10 is a flowchart showing a control operation of the control means of the positioning device at the time of position adjustment (alignment adjustment) in the present invention.
FIG. 11 is a diagram schematically showing four patterns in the present invention.
FIG. 12 is a diagram schematically showing two patterns in the present invention.
FIG. 13 is a flowchart showing the control operation of the control means of the positioning device during rough adjustment in position adjustment (alignment adjustment) according to the present invention.
FIG. 14 is a flowchart showing the control operation of the control means of the positioning device during rough adjustment in position adjustment (alignment adjustment) according to the present invention.
FIG. 15 is a flowchart showing the control operation of the control means of the positioning device at the time of coarse adjustment in position adjustment (alignment adjustment) in the present invention.
FIG. 16 is a flowchart showing the control operation of the control means of the positioning device at the time of coarse adjustment in position adjustment (alignment adjustment) in the present invention.
FIG. 17 is a flowchart showing the control operation of the control means of the positioning device during fine adjustment of the first embodiment in position adjustment (alignment adjustment) in the present invention.
FIG. 18 is a flowchart showing a control operation of the control means of the positioning device at the time of fine adjustment of the first embodiment in position adjustment (alignment adjustment) in the present invention.
FIG. 19 is a diagram for explaining rough adjustment in position adjustment (alignment adjustment) according to the present invention.
FIG. 20 is a diagram for explaining rough adjustment in position adjustment (alignment adjustment) in the present invention.
FIG. 21 is a diagram for explaining rough adjustment in position adjustment (alignment adjustment) in the present invention;
FIG. 22 is a diagram for explaining rough adjustment in position adjustment (alignment adjustment) in the present invention.
FIG. 23 is a diagram for explaining rough adjustment in position adjustment (alignment adjustment) in the present invention.
FIG. 24 is a diagram for explaining rough adjustment in position adjustment (alignment adjustment) in the present invention.
FIG. 25 is a diagram for explaining fine adjustment of the first embodiment in position adjustment (alignment adjustment) in the present invention.
FIG. 26 is a diagram schematically showing another four patterns in the present invention.
FIG. 27 is a diagram schematically showing two other patterns in the present invention.
FIG. 28 is a diagram for explaining fine adjustment according to the second embodiment in position adjustment (alignment adjustment) in the present invention;
FIG. 29 is a flowchart showing the control operation of the control means of the positioning device in edge processing according to the present invention.
FIG. 30 is a diagram for explaining edge processing in the present invention;
FIG. 31 is a diagram for explaining edge processing in the present invention;
FIG. 32 is a diagram for explaining edge processing in the present invention;
FIG. 33 is a diagram showing a first waveform and a second waveform in the present invention.
FIG. 34 is a diagram schematically showing an imaging region and a processing region in the present invention.
FIG. 35 is a diagram schematically showing a part of a processing region in the present invention.
FIG. 36 is a diagram showing a part of a processing region and a graph of luminance integrated values in the Y-axis direction corresponding to the part in the present invention.
FIG. 37 is a diagram showing a part of a processing region and a graph of luminance integrated values in the Y-axis direction corresponding to the part in the present invention.
FIG. 38 is a diagram showing a part of a processing area and a graph of luminance integrated values in the X-axis direction corresponding to the part in the present invention.
FIG. 39 is a diagram showing a part of a processing region and a graph of luminance integrated values in the X-axis direction corresponding to the part in the present invention.
FIG. 40 is a schematic diagram for explaining movement of the liquid crystal light valve during focus adjustment in the present invention.
FIG. 41 is a graph showing the relationship between dispersion values Vh and Vv for an image captured by a camera according to the present invention and the position of the liquid crystal light valve in the Z-axis direction when the dispersion values Vh and Vv are acquired.
FIG. 42 is a diagram schematically showing an image in the processing area when the position of the liquid crystal light valve in the Z-axis direction according to the present invention is changed.
FIG. 43 is a diagram schematically showing a configuration example of a projected image for focus adjustment in the present invention.
FIG. 44 is a diagram schematically illustrating a configuration example of a position adjustment projection image according to the present invention.
FIG. 45 is a diagram schematically illustrating a configuration example of a focus adjustment projection area and a position adjustment projection area in the present invention.
FIG. 46 is a diagram schematically illustrating a configuration example of a projection area for focus adjustment and a projection area for position adjustment in the present invention.
FIG. 47 is a diagram schematically illustrating a configuration example of a projection area for focus adjustment and a projection area for position adjustment in the present invention.
FIG. 48 is a diagram schematically showing a configuration example of a focus adjustment projection area and a position adjustment projection area in the present invention.
FIG. 49 is a diagram schematically illustrating a configuration example of a focus adjustment projection area and a position adjustment projection area in the present invention.
FIG. 50 is a diagram schematically illustrating a configuration example of a focus adjustment projection area and a position adjustment projection area in the present invention.
FIG. 51 is a diagram schematically showing projection areas on a screen by a liquid crystal light valve and imaging areas (three places) of each camera according to the present invention.
FIG. 52 is a diagram schematically showing projection areas on a screen by a liquid crystal light valve and imaging areas (three places) of each camera according to the present invention.
FIG. 53 is a diagram schematically showing projection areas on a screen by a liquid crystal light valve according to the present invention and imaging areas (four places) of each camera.
FIG. 54 is a diagram schematically showing an optical system of a conventional projection display apparatus.
[Explanation of symbols]
1 Positioning device
2 screens
3 Control means
4 memory
550 processing area
551 pixel section
552 gap
553 Y-axis direction gap
554 X-axis direction gap
555 Common gap
560 columns
570 lines
61-64 cameras
611, 621 Imaging area
612 side
631, 641 Imaging area
632, 633 sides
643 sides
71-74 Lighting device
8 3-axis table
81 3-axis table drive mechanism
9 3-axis table
91 3-axis table drive mechanism
11 Chuck
12 Support members
20 Optical block
21 Dichroic Prism
211, 212 Dichroic mirror surface
213-215
216 Output surface
22 Projection lens
23 Support
24-26 Liquid crystal light valve
251 Frame member
252 Through hole
253 Notch
27 Support member
28 Fixed plate
281 opening
282 screw holes
29 Fixed plate
291 opening
292 Through hole
293 protrusion
31 screws
32 wedges
33 Adhesive
411 to 413 Imaging area
421 to 423 Imaging area
431 to 434 Imaging area
100 projection area
101a, 101b Corner
101c, 101d corner
103a, 103b side
104a, 104b side
110 Projection area
111a, 111b corner
111c, 111d corner
112a, 112b edge
112c, 112d edge
113a, 113b side
114a, 114b side
115 Non-projection area
116 border
121-124 positions
125a, 125b center
125c, 125d center
126, 127 straight lines
128 specific position
129a, 129b position
131, 141 projected image
300 Projection display
301 Light source
302, 303 Integrator lens
304, 306, 309 Mirror
305, 307, 308 Dichroic mirror
310-314 Condensing lens
315 Dichroic Prism
316-318 Liquid crystal light valve
319 Projection lens
320 screens
S100 to S120 steps
S10a processing
S150 step
S201 to S232 steps
S300 Coarse adjustment
S30A-S30H treatment
Steps S301 to S329
S350 Fine adjustment
Steps S351 to S359
Steps S401 to S415
S90a-S90d processing
Steps S901 to S910
Steps S921 and S922
Steps S931 and S932
Steps S941 to S948

Claims (4)

A positioning method for positioning the light valve of a projection display device that projects a substantially square image formed by a light valve by a projection optical system,
The same focus adjustment image as the image area that can be projected is projected onto the screen, and four corners inside the focus adjustment image are captured by four cameras, respectively, to obtain an electronic image, and the focus of the electronic image is obtained. Perform focus adjustment to displace the light valve so that the state approaches the target state,
An image for position adjustment that is included in an image area that can be projected and is smaller than the image for focus adjustment is projected onto the screen, and four corners of the edge of the image for position adjustment are captured by the four cameras, and an electronic image And adjusting the position of the light valve so that the specific position of the electronic image approaches the target state.   The four cameras are fixed, and each of the four cameras captures an image when the focus adjustment is performed, and each of the four cameras captures an image when the position adjustment is performed. 2. The light valve positioning method according to claim 1, wherein the region is the same region for each of the cameras.   The light valve positioning method according to claim 1, wherein the focus adjustment is performed a plurality of times, and the position adjustment is performed a plurality of times.   The positioning of the light valve according to any one of claims 1 to 3, wherein the projection type device has three light valves corresponding to red, green, and blue, and performs the positioning for each of the three light valves. Method.

Images