JP3719775B2 - Image input device - Google Patents

Description

【００４６】
以上のような操作を、色フィルタ板２８のＲ、ＧおよびＢの各色フィルタを順次光路Ｌに挿入して行い、Ｒ、ＧおよびＢのそれぞれに対応する光源絞りテーブルを作成する。入力装置１０は、この光源絞りテーブルを用いて、照度設定を行い、また、プレスキャンや本スキャンの際の絞り２６の開放値を制御する。
この光源絞りテーブルは、読取光の光源であるハロゲンランプ２５やレンズユニット９２を交換した場合等、光学系の特性に大きな影響を与える変更があった場合には、新たに作成し直す必要がある。
【００４７】
このようにして得られた光源絞りテーブルは、光路中にＮＤフィルタを挿入して作成された、絞り２６の開放時の出力Ｃ₅₀₀ を基準とした、開放値Ｉと絞り規格値（すなわちＣＣＤセンサ２０の出力）との相対的な関係を示すものであり、必ずしも、ある開放値における、絶対的な出力（濃度）を示すものではない。
ＣＣＤセンサ２０を用いた画像読取は、最高出力（すなわち、最低濃度部）がＣＣＤセンサ２０の飽和出力となるように行うのがＳ／Ｎ比の点で好ましく、絞り２６の開放値は、このように設定する必要があるが、この光源絞りテーブルだけでは、所望の出力を得るための開放値を得ることができない。
【００４８】
そのため、読取光の光量を所望する出力が得られる状態にするための、光源部１４の基準状態の設定すなわち画像読取の照度設定を行う必要がある。
言い換えれば、照度設定は、フィルムが無い状態において、ＣＣＤセンサ２０の出力が飽和出力となるように光源部１４の状態を設定するものである。
【００４９】
まず、ハロゲンランプ２５への印加電圧を所定値に設定し、さらに、ＣＣＤセンサ２０の飽和出力Ｃ_ref を目標値として設定する。
次いで、フィルムが無い状態でＣＣＤセンサ２０の出力が飽和近傍になると予測される初期絞り規格値に絞り２６の開放値Ｉを調整し、この状態で、例えば、初めに色フィルタ板２８のＧフィルタ２８Ｇを光路Ｌに挿入し、ＣＣＤセンサ２０の出力ＧＣ_out を測定する。
次いで、出力ＧＣ_out を目標値Ｃ_ref で除して対数を取り、濃度値ＧＸを算出する。つまり下記式［１］によって濃度値ＧＸを求める。
ＧＸ＝−ｌｏｇ（ＧＣ_out ／Ｃ_ref ） …… ［１］
照度設定は、この濃度値ＧＸ（すなわち出力ＧＣ_out ）を所定の範囲内にすることを目的として、光源部１４の状態を調整する。
【００５０】
照度設定方法の一つとして、算出した濃度値ＧＸに応じて、絞り２６の開放値Ｉを調整して濃度値ＧＸを所定の範囲内にする方法が例示される（以下、これを方法１とする）。
式［１］で算出された濃度値ＧＸは、その開放値Ｉにおける出力ＧＣ_out が目標値Ｃ_ref に対して濃度値換算でどれだけ過剰もしくは足りないかを示す数値である。従って、濃度値ＧＸをフィードバックすることにより、ＧＸを目的範囲に入れる（近付ける）ことができる。
すなわち、前述のようにして最初の濃度値ＧＸを算出し、その値が所定範囲内に入っている場合には、その際の絞り規格値をＧ画像読取の開放規格値ＧＳ_set として絞り制御装置１０４に記憶する。ＣＣＤセンサ２０の出力ＧＣ_out が飽和している場合には絞り２６を適当量閉塞し、濃度値ＧＸが所定範囲に入っていない場合には、前述の光源絞りテーブルを用いて濃度値ＧＸ分（これに相当する絞り規格値分）だけ絞り２６の開放値を調整して、再度測定を行い、式［１］を用いて濃度値ＧＸを算出する。この操作を、濃度値ＧＸが所定範囲に入るまで繰り返し、所定範囲に入った際の絞り規格値を開放規格値ＧＳ_set を決定して絞り制御装置１０４に記憶する。
【００５１】
照度設定方法の別の方法として、光源であるハロゲンランプ２５に印加する電圧を調整することにより、濃度値ＧＸを目的範囲内にする方法が例示される（以下、これを方法２とする）。
周知のように、ハロゲンランプ２５は、所定の範囲内であれば、ハロゲンサイクル、色温度、寿命等に悪影響を与えることなく印加電圧設定値を変更することができ、これにより、光量を調整することができる。この方法は、これを利用するものである。なお、前述の方法１では、ハロゲンランプ２５の印加電圧は、所定の設定値に固定される。
【００５２】
前述のように最初の濃度値ＧＸを算出し、濃度値ＧＸが所定範囲内に入っている場合には、ハロゲンランプ２５への印加電圧をそこで固定し、その状態の絞り規格値を開放規格値ＧＳ_set として絞り制御装置１０４に記憶する。
ＣＣＤセンサ２０の出力ＧＣ_out が飽和している場合にはハロゲンランプ２５への印加電圧を適当量低減し、濃度値ＧＸが所定範囲内に入っていない場合には、ハロゲンランプ２５への印加電圧を所定の刻み幅だけ増加もしくは低減して光量を調整し、一定時間経化後に光量が安定してから、出力ＧＣ_out を測定して式［１］を用いて濃度値ＧＸを算出する。この操作を、濃度値ＧＸが所定範囲に入るまで繰り返し、濃度値ＧＸが所定範囲内に入ったところで、ハロゲンランプ２５への印加電圧を固定し、その状態の絞り規格値を開放規格値ＧＳ_set として絞り制御装置１０４に記憶する（従って、絞り規格値は初期値となる）。
なお、照度設定の途中でハロゲンランプ２５への印加電圧が調整可能範囲内を超えてしまう場合には、ここでハロゲンランプ２５への印加電圧を固定して、これ以降は前記方法１を用い、濃度値ＧＸが所定範囲内に入るまで絞り２６の開放値Ｉを調整し、濃度値ＧＸが所定範囲となったところで、その際の絞り規格値を開放規格値ＧＳ_set として絞り制御装置１０４に記憶する。
【００５３】
このようにして、ハロゲンランプ２５への印加電圧が決定され、Ｇ画像読取の開放規格値ＧＳ_set が設定されたら、次いで、例えば、色フィルタ板２８のＲフィルタ２８Ｒを光路Ｌに挿入し、前記方法１のみを用いてＲ画像読取の開放規格値ＲＳ_set を設定し、最後に、色フィルタ板２８のＢフィルタ２８Ｂを光路Ｌに挿入し、同様に前記方法１のみを用いてＢ画像読取の開放規格値ＢＳ_set を設定する。
【００５４】
このようにして、ハロゲンラン２５への印加電圧を決定し、開放規格値ＧＳ_set 、ＲＳ_set 、およびＢＳ_set を設定して、照度設定を終了する。
なお、光源であるハロゲンランプ２５の光量は、劣化や、汚れや埃等の堆積等によって経時的に変化する。そのため、この照度設定は、入力装置１０の立ち上げの際等に、毎回行うのが好ましい。
また、以上説明した光源絞りテーブルの作成や照度設定におけるＣＣＤセンサ２０からの出力は、全画素のデータを用いるとシェーディング等の影響により正確な値を得ることができないので、中央部分、例えば、図示例のように、ＣＣＤセンサ２０が１３８０×９２０画素のＣＣＤセンサであれば、中央部分の３２×８画素を用い、その加算平均値を用いるのが好ましい。
【００５５】
この開放規格値は、プレスキャンの際の絞り２６の開放値の基準であるが、入力装置１０は、フィルムサイズやトリミングに応じてレンズユニット９２のズームレンズ部９６の倍率を調整して画像読取を行う装置であり、ズームレンズは倍率に応じて透過光量が変動するために、ＣＣＤセンサ２０に入射する投影光の光量が倍率によって変動し、すなわち画像の読取条件が倍率に影響を受けるため、倍率によっては、適正な画像読取ができない場合がある。
これに対し、本発明にかかる入力装置１０においては、絞り制御装置１０４にズームレンズ部９６の倍率に応じた絞り２６の補正テーブル（ズーム光量補正テーブル）が記憶されており、各開放規格値ＧＳ_set 、ＲＳ_set 、ＢＳ_set に、ズームレンズ部９６の倍率に応じた補正を加えて絞り２６の開放値を設定してプレスキャンを行う。従って、本発明の入力装置１０によれば、ズームレンズ部９６の倍率によらず、常時安定して適正な画像読取を行うことができる。
【００５６】
ズームレンズ（ズームレンズ部９６）の倍率変化に応じた有効Ｆナンバーの変動に基づく相対的な透過光量の変動量は、設計的もしくは実験的に予め求めることができる。従って、前述の光量絞りテーブル作成および照度設定に用いた倍率を基準として、倍率に応じたズームレンズ部９６の相対的な光量変動すなわちＣＣＤセンサ２０に結像する投影光の照度比も設計的もしくは実験的に予め求めることができる。
図１１に、ズームレンズ部９６の倍率と照度比との関係の一例を示す。光量絞りテーブル作成および照度設定は、入力装置１０が最も読み取ることが予想されるフィルムサイズ（通常は１３５サイズ）に応じた倍率で行うのが好ましく、図示例の入力装置１０は、０．４４倍が基準となっている。
【００５７】
次いで、この照度比を濃度変換（Ｌｏｇ変換）することにより、０．４４倍を基準とした、倍率変化による濃度差を得ることができる。図１２に図１１の照度比を濃度変換した例を示す。この濃度差（すなわち絞り２６の開放値）と倍率との関係を示すテーブルを記憶しておき、これを用いて、ズームレンズ部９６の倍率に応じた濃度補正すなわち絞り２６の開放値の補正を行うことにより、倍率によらず、一定の条件で画像読取を行うことができる。
図示例の入力装置１０においては、図１２の濃度差を前記絞り規格値と同様に規格化（１２８倍）して補正絞り規格値とし、各補正絞り規格値に対応する倍率を求めてテーブル化したズーム光量補正テーブルが絞り制御装置１０４に記憶されている。
【００５８】
下記表に、図１２より得られたズーム光量補正テーブルを示す。なお、下記表において、ズームレンズ部の倍率は「倍率」、補正絞り規格値は「補正」と、それぞれ示す。ここで前述のように、０．００１倍刻みで倍率を調整する際には、０．４００〜０．４０９倍までは−６、０．４１０〜０．４１９倍までは−４（あるいは、その逆。装置特性に応じて決定すればよい。）等でズーム光量補正テーブルを使用すればよい。

【００５９】
前述の制御装置１０２は、例えば、装着されたキャリア種の判別やオペレータによる入力でフィルムサイズを判別し、これに応じてズームレンズ部９６の倍率を決定して、あるいは、トリミングのためのオペレータによる操作によって、倍率調整モータ９３を駆動して倍率調整を行う。
これと同時に、倍率の情報は絞り制御装置１０４にも送られ、絞り制御装置１０４は、ズーム光量補正テーブルを用いてズームレンズ部９６の倍率に応じた補正絞り規格値を読み出して、補正絞り規格値を加算して前述の各開放規格値ＧＳ_set 、ＲＳ_set 、ＢＳ_set を補正し、これにより得られた絞り規格値をプレスキャンの絞り規格値として、光量絞りテーブルを用いて絞り２６の開放値を決定し、モータ２７を駆動してプレスキャンにおける絞り２６を調整する。
なお、キャリア種の判別方法としては、キャリアベース１６にキャリアを装着することによるマイクロスイッチの押圧、キャリアと入力装置１０との接続によるコネクタ種の判別、キャリアからの判別信号の出力等、公知の方法が利用可能である。
【００６０】
本発明にかかる入力装置１０においては、プレスキャンにおける絞り２６の開放値は基本的に以上のように決定される。ここで、ＣＣＤセンサ２０を用いた画像読取では、透過光量が最大あるいは最大近傍となる最低濃度点で出力が飽和になるように行われるのがＳ／Ｎ比の点で好ましいが、フィルムはベース濃度を持っており、フィルムを光路Ｌに挿入して読み取りを行うと、透過光量（ＣＣＤセンサ２０の出力）は必ず低下する。
従って、プレスキャンを行う際には、フィルムのベース濃度分だけ光量を多くすなわち絞り２６を開放して読み取りを行うのが好ましく、例えば、予めフィルムのベース濃度から、それに対応する絞り規格値を算出しておき、前述の開放規格値と倍率に応じた補正絞り規格値とから得られたプレスキャンの開放規格値を、ベース濃度に対応する絞り規格値で補正して、これにより得られた絞り規格値によって絞り２６の開放値を決定してもよい。
【００６１】
本発明にかかる入力装置１０は、基本的に上記構成を有するものであるが、以下にその作用について説明する。
入力装置１０の主電源を入れて装置を起動させると、まず、前述の照度設定が行われる。
すなわち、ハロゲンランプ２５の印加電圧を所定値に設定して点灯し、さらに、ＣＣＤセンサ２０の飽和出力Ｃ_ref が目標値として設定され、絞り２６の開放値が初期設定値に設定され、光量が安定した時点で、Ｇフィルタ２８Ｇが光路Ｌに挿入され、出力ＧＣ_out が測定されてＧＸが算出される。
ここでは、Ｇ画像読取の開放規格値ＧＳ_set の設定を前記方法２で行うとして、ＧＸが所定範囲内に入っていなければ、ハロゲンランプ２５への印加電圧を所定量増加して光量を増加させ、光量が安定してから、濃度値ＧＸを算出する操作を、濃度値ＧＸが所定範囲に入るまで繰り返し、濃度値ＧＸが所定範囲内に入ったところで、ハロゲンランプ２５への印加電圧を固定し、その際の絞り規格値を開放規格値ＧＳ_set として絞り制御装置１０４に記憶する。なお、電圧調整によって濃度値ＧＸが所定範囲内にならなかった場合は、さらに、方法１を用いて開放値を調整して開放規格値ＧＳ_set を設定するのは前述のとおりである。
【００６２】
次いで、Ｒフィルタ２８Ｒを光路Ｌに挿入して、前述のように、方法１による開放規格値ＲＳ_set の設定、すなわち、ＧＸの算出および絞り２６の開放値の調整を繰り返してＲ画像読取における開放規格値ＲＳ_set を設定して絞り制御装置１０４に記憶し、同様に、Ｂ画像読取における開放規格値ＲＳ_set を設定して絞り制御装置１０４に記憶し、ハロゲンランプ２５への印加電圧、開放規格値ＧＳ_set 、ＲＳ_set 、およびＢＳ_set を設定して、照度設定を終了する。
【００６３】
オペレータは、読み取る原稿の形態に応じたキャリアを図４に示すようにキャリアベース１６に装着する。ここでは、仮にストリップスＡを読み取るとして、図３（ａ）に示されるように、フィルムキャリア２２をキャリアベース１６上の所定位置に装着する。
次いで、フィルム圧着ユニット５２の圧着部材６０を上方に上げ、ストリップスＡに撮影された１枚目の画像が読取位置ＺとなるようにストリップスＡをフィルムキャリア２２に装填する。
【００６４】
他方、制御部２１の制御装置１０２は、装着されたキャリアからフィルムのサイズを判別し、フィルムサイズに応じて倍率を決定して調整モータ９３を駆動してズームレンズ部９６の倍率を調整し、同時に、絞り制御装置１０４に倍率の情報を出す。
倍率の情報を受けた絞り制御装置１０４は、ズーム光量補正テーブルから倍率に応じた補正絞り規格値を読み出して、各開放規格値ＧＳ_set 、ＲＳ_set 、ＢＳ_set に補正絞り規格値を加算し、これにより得られた絞り規格値をプレスキャンの絞り規格値として、光量絞りテーブルを用いてプレスキャンにおける絞り２６の開放値を決定する。
【００６５】
以上の操作が終了した後、読取開始の指示が出されると、必要に応じて、自動焦点調整が行われ、次いで、プレスキャンおよび本スキャンが開始される。
プレスキャンでは、例えば、最初にＧフィルタ２８Ｇが光路Ｌに挿入され、絞り制御装置１０４は前記光量絞りテーブルを用いて、前述のように設定したプレスキャンの絞り規格値から絞り２６の開放値を読み出してモータ２７を駆動して絞り２６を調整し、絞り２６およびＧフィルタ２８Ｇによって調光された光がストリップスＡを透過して、画像を担持する投影光がレンズユニット９２によってＣＣＤセンサ２０に結像され、Ｇ画像が読み取られる。
Ｇ画像の読み取りが終了すると、色フィルタ板２８が回転して、例えば、Ｒフィルタ２８Ｒが光路Ｌに挿入されて、同様に絞り２６が設定された絞り規格値に応じて調整されてＲ画像の読み取りが行われ、さらに、同様にして、Ｂ画像が読み取られ、プレスキャンが終了する。
【００６６】
ＣＣＤセンサ２０によって読み取られたプレスキャン画像は、順次画像処理装置１００に送られ、Ａ／Ｄ変換、Ｌｏｇ変換等の所定の処理を施されて画像情報とされ、濃度ヒストグラムの作成、画像処理条件の設定等が行われ、また、得られた画像がディスプレイ１０６に表示される。
さらに絞り制御装置１０４は、画像処理装置１００が作成した濃度ヒストグラムから、例えば最低濃度に応じて本スキャンにおける絞り規格値をＧ，Ｒ，Ｂと順次決定する。
【００６７】
プレスキャンのＢ画像読取が終了すると、再度Ｇフィルタ２８Ｇが光路Ｌに挿入されて、続けて本スキャンのＧ画像読取が開始され、絞り制御装置１０４が決定した本スキャンのＧ画像読取の絞り規格値に応じて光源絞りテーブルを用いて絞り２６の開放値を決定し、モータ２７を駆動して絞り２６の開放値を調整し、プレスキャンと同様に、Ｇフィルタ２８Ｇおよび絞り２６によって調光された光がストリップスＡを透過して、投影光がレンズユニット９２によってＣＣＤセンサ２０に結像され、原稿のＧ画像が読み取られ、画像処理装置１００に送られ、以下、同様にして、Ｒ画像およびＢ画像が読み取られ、画像処理装置１００に送られる。
ＣＣＤセンサ２０によって読み取られた本スキャン画像は、画像処理装置１００において、Ａ／Ｄ変換、暗時補正、Ｌｏｇ変換等の所定の処理を施されて画像情報とされ、さらに、プレスキャンに応じて設定された処理条件に応じて色／濃度補正等を施されて、出力のための画像情報とされ、画像記録装置Ｐに出力される。
【００６８】
このようにして最初の画像読取を終了すると、その旨の信号が制御部２１からフィルムキャリア２２に出され、圧着部材６０が上方に回動してストリップスＡを開放し、次いで、搬送手段５０が駆動してストリップスＡを矢印ｘ方向に搬送し、画面検出センサ５４による検出結果に応じて搬送を停止し、次ぎの画像が読取位置Ｚに搬送される。
次いで、圧着部材６０が下方に回動してストリップスＡを固定し、先と同様にして、プレスキャンおよび本スキャンが行われる。
【００６９】
以上、本発明の画像入力装置について詳細に説明したが、本発明は上述の例に限定はされず、本発明の要旨を逸脱しない範囲において、各種の変更および改良を行ってもよいのはもちろんである。
【００７０】
【発明の効果】
以上、詳細に説明したように、本発明の画像入力装置は、ズームレンズによって倍率を調整して、フィルムに撮影された画像から所望の部分をトリミングした画像読取や、フィルムサイズによらず所定のサイズの投影光をイメージセンサに結像して画像読取を行うことができ、しかも、倍率に影響を受けない適正な画像読取を行うことができる。
【図面の簡単な説明】
【図１】 本発明の画像入力装置の一例の一使用態様の概略斜視図である。
【図２】 図１に示される画像入力装置の光源部の概略斜視図である。
【図３】 図２に示される光源部の（可変）絞りの作用を示す概念図である。
【図４】 （ａ）および（ｂ）は、図１に示される画像入力装置におけるキャリア交換の操作を示す概略斜視図である。
【図５】 図１に示される画像入力装置に装着されるトリミングキャリアのキャリア本体の概略平面図である。
【図６】 図１に示される画像入力装置に装着されるトリミングキャリアの概略平面図である。
【図７】 図６に示されるトリミングキャリアに用いられるストリップス保持板の概略斜視図である。
【図８】 カラー画像読取における開放値とＣＣＤセンサの出力との関係の一例を示すグラフである。
【図９】 図８に示されるグラフにおけるＣＣＤセンサの出力を絞り開放時を基準として濃度値に変換したグラフである。
【図１０】 図９に示されるグラフの濃度値を規格化したグラフである。
【図１１】 ズームレンズの倍率と照度比との関係の一例を示すグラフである。
【図１２】 図１１に示されるグラフの照度比を濃度差に変換したグラフである。
【符号の説明】
１０ （画像）入力装置
１２ 光学フレーム
１４ 光源部
１６ キャリアベース
１８ 結像部
２０ ＣＣＤセンサ
２１ 制御部
２２ フィルムキャリア
２４ トリミングキャリア
２５ 光源
２６ 絞り
２７ モータ
２８ 色フィルタ板
３０ 拡散ボックス
３２ 開口
３４，３６ 案内レール
３８，４０，４２，４４ 溝
４６，６６ 本体
４８ 案内溝
５０ 搬送手段
５２ フィルム圧着ユニット
５４ 画面検出センサ
５６ モータ
５８ 搬送ローラ
６０ 圧着部材
６２ 軸
６４ 回動手段
６６ キャリア本体
６８ ベース
７０ 保持板
７２ 貫通孔
７４ 凹部
７６，８８ 開口
７８ 規制部材
８０ 当接部
８２ 押圧部材
８４ 開口
８５ ストリップス保持板
８６ 板材
９０ 定盤
９２ レンズユニット
９４ 焦点調整モータ
９６ ズームレンズ部
９８ 焦点調整レンズ部
１００ 画像処理装置
１０２ 制御装置
１０４ 絞り制御装置[0001]
BACKGROUND OF THE INVENTION
The present invention belongs to the technical field of an image input device for photoelectrically reading an image taken on a film, which is used in a photographic printing apparatus using digital exposure.
[0002]
[Prior art]
Currently, the images taken on photographic films such as negative films and reversal films (hereinafter referred to as films) are printed on photographic materials such as photographic paper. This is done by so-called direct exposure.
On the other hand, in recent years, a printing apparatus using digital exposure, that is, image information recorded on a film is photoelectrically read and subjected to various image processing to obtain digital image information for recording. Development of digital photo printers for printing images (latent images) by scanning and exposing a photosensitive material with recording light modulated accordingly has been progressing.
[0003]
In a digital photo printer, the exposure condition is determined by photoelectrically reading a film and performing color density correction by signal processing. Therefore, the exposure time per image is short, and the exposure time is also an image. Since it is constant according to the size, it is possible to perform printing more quickly than conventional surface exposure.
In addition, editing such as image composition and image division and image processing such as color / density adjustment can be freely performed, and a finished print subjected to editing and image processing can be output according to the application. Further, since the finished print image can be stored as image information on a recording medium such as a floppy disk, it is not necessary to prepare a film as a manuscript at the time of reprinting or the like, and it is not necessary to determine exposure conditions again, so that it is quick and simple. Can work on.
In addition, conventional direct exposure printing cannot reproduce all images recorded on film etc. in terms of resolution, color / density reproducibility, etc., but it is recorded on film by a digital photo printer. A print that reproduces almost 100% of the existing image (density information) can be output.
[0004]
Such a digital photo printer basically includes an image input device that reads an image recorded on a film, a setup device that processes the read image to determine exposure conditions for image recording, and the determined exposure conditions. It comprises an image recording apparatus that scans and exposes a photosensitive material to develop it.
The present applicant has invented various image reading apparatuses and methods for realizing such a digital photo printer, and disclosed in Japanese Patent Laid-Open Nos. 6-217091, 6-233052, and 6-245062. This is proposed, and the apparatus outline of the digital photo printer is disclosed in the publication.
[0005]
[Problems to be solved by the invention]
By the way, an image input device used in a digital photo printer enters reading light emitted from a light source into a film to obtain projection light carrying an image photographed on the film, and this projection light is obtained by an imaging lens. An image on a film is read by forming an image on an image sensor such as a CCD sensor and performing photoelectric conversion.
Here, although the size of the film read by the digital photo printer is various, the size of the projection light imaged on the image sensor is preferably as uniform as possible in terms of subsequent image processing and the like. In view of the resolution of image reading, the maximum size that can be read by the light receiving surface of the image sensor is preferable. It is also possible to create a finished print by cutting out and enlarging (trimming) a part of the image photographed on the film.
[0006]
Therefore, in an image input device, a so-called zoom lens is used as an imaging lens, the magnification is adjusted according to the size of the film, and the maximum size at which the image sensor can receive the projection light imaged on the image sensor It is preferable that the image is read or the magnification is arbitrarily adjusted to trim a desired portion of the image photographed on the film so that the image sensor can receive the maximum size.
However, in the zoom lens, the F-number changes depending on the magnification and the amount of transmitted light varies, so the amount of projection light incident on the image sensor varies according to the magnification, and the output value from the image sensor varies. That is, in an image input device using a zoom lens, the reading condition is affected by the magnification, and depending on the magnification, there are cases where proper image reading cannot be performed.
[0007]
  An object of the present invention is an image input device used in a digital photo printer that creates a photographic print using digital exposure, and can adjust the magnification of the projection light of the film with a zoom lens, and the image photographed on the film The image can be read by trimming a desired part from the image, or the image can be read by forming a projection light of a predetermined size on the image sensor regardless of the film size.ofAn object of the present invention is to provide an image input device capable of performing proper image reading without being affected.
[0008]
[Means for Solving the Problems]
  To achieve the above object, the present inventionImage input device according toIsAn image input device having a pre-scan mode and a fine scan mode,A light source unit that emits reading light emitted from a light source and whose light amount is adjusted by a light source aperture to a film; an image sensor that photoelectrically reads projection light that has passed through the film; and forms an image of the projection light on the image sensor. An imaging lens whose magnification can be adjusted, a correction table for a light source aperture preset according to the magnification of the imaging lens, and the magnification lens according to the magnification of the imaging lensLight source apertureAdd correction using the correction table,In the pre-scan modeControl means for controlling an open value of the light source diaphragm.Features.
  In the image input device according to the present invention, it is preferable that the correction value of the open value of the light source diaphragm in the correction table of the light source diaphragm is configured to be capable of substantially continuous correction.
  Moreover, it is preferable that the said control means is what normalized the output of the said image sensor for every color, when the said film is a color film.
  In addition, the correction table of the light source aperture includes the illuminance of the light source and / or the open value of the light source aperture so that the output from the lowest density portion of the projection light of the image sensor does not exceed the saturation output of the image sensor. It is preferable that a correction value for the open value of the light source diaphragm corresponding to the magnification of the imaging lens as a reference is obtained.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an image input apparatus according to the present invention will be described in detail based on a preferred embodiment shown in the accompanying drawings.
[0010]
FIG. 1 shows a schematic perspective view of an example of the image input apparatus of the present invention (the control unit 21 is shown in a block diagram).
An image input apparatus 10 (hereinafter referred to as an input apparatus) 10 shown in FIG. 1 is a strip of a long negative or reversal film on which a large number of images are taken, usually a single reversal film. A device that photoelectrically reads an image photographed on a slide B fixed to a (mount), an optical frame 12, a light source unit 14, a carrier base 16, an imaging unit 18, a CCD sensor 20 as an image sensor, and a control unit. 21 and a film carrier 22 and a trimming (slide) carrier 24 that can be attached to the carrier base 16 (FIG.andFIG.Etc.) and the like.
[0011]
In the input device 10, a carrier corresponding to reading is mounted on the carrier base 16, and the reading light from the light source unit 14 is applied to the strip A or the slide B (hereinafter collectively referred to as a film) positioned at the reading position Z. Is projected onto the image to obtain a projection light carrying the image photographed on the film, the projection light is imaged on the CCD sensor 20 by the imaging unit 18 and subjected to photoelectric conversion, and the obtained output signal (image data signal) ) Is processed in the control unit 21 to photoelectrically read an image photographed on the film.
[0012]
FIG. 2 shows a schematic diagram of the light source unit 14.
In the input device 10, the light source unit 14 is for obtaining projection light carrying an image photographed on the film by irradiating read light whose light amount is adjusted from below the film. It is located below and has a halogen lamp 25, a diaphragm 26, a color filter plate 28, and a diffusion box 30.
In addition to the above, the light source unit 14 is provided with a cooling fan or the like for cooling various members such as the halogen lamp 25.
[0013]
The halogen lamp 25 is a light source for reading light, and in the illustrated input device 10, as a preferred mode, the amount of light can be adjusted by adjusting the voltage applied to the halogen lamp 25.
In the present invention, as the light source, various known light sources capable of emitting reading light having a sufficient amount of light for image reading by the CCD sensor 20 can be used. For example, a xenon lamp, a mercury lamp, etc. are exemplified in addition to the halogen lamp. Is done.
[0014]
The diaphragm 26 is a light source diaphragm for adjusting the amount of reading light incident on the film. In the illustrated example, the diaphragm 26 includes two ND filters 26a and 26b having different amounts of passing light in the plane direction in which a logarithmic curve is formed in the light shielding portion. , A variable aperture using a moving means (not shown) using the motor 27 as a drive source.
[0015]
As shown in FIGS. 2 and 3, the ND filters 26a and 26b face the open side with few light-shielding parts facing each other, and the optical axis L (in FIG. 3, the direction perpendicular to the paper surface) corresponds to the maximum open part. Is arranged on a plane perpendicular to the optical axis L, and is moved by the motor 27 by the arrow a in the plane direction.₁Direction and arrow a₂By moving the ND filters 26a and 26b and moving them toward and away from each other, the passage area of the reading light emitted from the halogen lamp 25, that is, the open value is adjusted to adjust the amount of light passing through the reading light, and the reading incident on the film. Adjust the amount of light.
In the illustrated example, the motor 27 is a pulse motor, and the positions of the ND filters 26a and 26b, that is, the opening value of the diaphragm 26 are managed by pulses. The driving of the motor 27 is controlled by the aperture control device 104 using a light source aperture table that indicates the relationship between the aperture value of the aperture 26 and the output of the CCD sensor 20, which will be described later.
[0016]
There are no particular limitations on the means for moving the ND filters 26a and 26b using the motor 27 as a drive source, and various known plate-like object moving means can be used. For example, means using screw transmission, means using a cam, Examples include means using a link mechanism and means using a rack and pinion.
Further, the light source diaphragm used in the present invention is not limited to the one using an ND filter having a different amount of passing light in the plane direction as in the illustrated example, but is known variable such as an iris diaphragm or a diaphragm using a plurality of diaphragm plates. Various apertures are available.
[0017]
The color filter plate 28 has three through holes formed in a disk-shaped plate material, and each of the three colors of an R (red) filter 28R, a G (green) filter 28G, and a B (blue) filter 28B is formed in each through hole. A filter is attached, and is configured to be rotatable about a shaft 28a by a rotating means (not shown).
At the time of image reading, the R filter 28R, the G filter 28G, and the B filter 28B are sequentially inserted into the optical path L, whereby the image photographed on the film is separated into the three primary colors R, G, and B and read.
[0018]
Here, the sensitivity of the CCD sensor 20 to R, G, and B light is not uniform, the sensitivity to B light is low, and the sensitivity to R light is high. Moreover, the light from the halogen lamp 25 has a relatively large R component. Accordingly, the output from the CCD sensor 20 by film reading is high in R and low in B, and the output of the three colors cannot be balanced.
Therefore, in the illustrated input device 10, by adjusting the spectral characteristics of each color filter and the size of the through hole in which each color filter is mounted, the amount of light passing through the R filter 28R is minimized and the amount of light passing through the B filter 28B is reduced. At the highest level, the R, G, and B outputs from the CCD sensor 20 are balanced.
[0019]
The diffusion box 30 is for making the amount of reading light incident on the film uniform in the surface direction of the film without unevenness.
In the illustrated example, the diffusion box 30 has a ground glass 30 on the lower surface of a rectangular column 30a whose inner surface is a mirror surface and whose upper and lower surfaces are open.cWith a milky white acrylic plate 30 on the topbIn addition to this, various known light diffusion means such as opal glass can be used.
[0020]
A carrier base 16 is disposed above the light source unit 14.
The carrier base 16 is a part that holds various carriers such as the film carrier 22 and the trimming carrier 24 on the upper surface thereof and holds them in a predetermined position, and is fixed perpendicularly to the optical frame 12.
[0021]
As shown in FIG. 4, an opening 32 through which reading light from the light source unit 14 passes is formed in a portion corresponding to the optical axis L of the carrier base 16.
Further, guide rails 34 and 36 are formed on the upper surface of the carrier base 16 in a direction from the front side in the drawing toward the optical frame 12, that is, in an arrow y direction orthogonal to an arrow x direction serving as a film transport direction. .
Corresponding to the guide rails 34 and 36, grooves 38 and 40 are formed on the bottom surface of the film carrier 22, and grooves 42 and 44 (see FIG. 5) are formed on the bottom surface of the trimming carrier 24, respectively. .
Each carrier placed on the upper surface of the carrier base 16 is defined in the position in the arrow x direction by the guide rails 34 and 36 and the corresponding groove, and in contact with the optical frame 12, the direction in the arrow y direction. Are positioned at a predetermined position on the carrier base 16 so that they can be placed freely.
[0022]
The film carrier 22 intermittently conveys the strips (sleeve) A in the direction of the arrow x so that each image photographed on the strips A is placed at a predetermined position on the optical axis L, that is, at the opening 32 of the carrier base 16. It is sequentially conveyed to the corresponding reading position Z and used for reading.
[0023]
As described above, the groove 38 corresponding to the guide rail 34 of the carrier base 16 and the guide rail are formed on the bottom surface of the main body 46 of the film carrier 22.36The groove | channel 40 corresponding to is formed.
Further, a guide groove 48 is formed on the upper surface of the main body 46 so as to extend in a conveying direction indicated by an arrow x and a position intersecting the optical axis L. The guide groove 48 is a groove having substantially the same width as that of the strip A, and the strip A is inserted in the guide groove 48 and conveyed in the direction of the arrow x with the longitudinal direction coinciding with the conveyance direction, and each image is sequentially read. It is conveyed to position Z. Therefore, the depth of the guide groove 48 is set so that the image surface of the strips A is at a predetermined position in the optical axis L direction (depth of focus direction).
Further, an opening through which the reading light from the light source unit 14 passes is formed at the reading position Z of the main body 46 of the film carrier 22. This opening also serves as a mask for restricting the reading light incident on the strip A.
[0024]
In the guide groove 48, the transport unit 50, the film crimping unit 52, and the screen detection sensor 54 are arranged from the upstream in the x direction to the downstream.
The conveying means 50 conveys the strips A in the direction of the arrow x, and includes a motor 56 and a conveying roller 58. For example, when the image comes to the reading position Z according to the detection result by the screen detection sensor 54. When it stops and receives a signal indicating completion of reading from the control unit 21, the conveyance is started again, and the next image is conveyed to the reading position Z.
The film pressing unit 52 presses the periphery of the image of the strip A to the guide groove 48 at the reading position Z, thereby correcting the curl of the strip A at the time of image reading and bringing the entire surface of the image to a predetermined position in the optical axis L direction. It is to hold. Such a film crimping unit 52 is composed of a crimping member 60 and a rotating means 64 that pivots the crimping member 60 in the direction of the arrow b about the shaft 62, and the crimping member 60 conveys the strips A. Sometimes it is pivoted upward by the pivoting means 64 and pivoted downward during reading to press the strip A at the reading position Z.
The screen detection sensor 54 is a known optical sensor that detects an image or a DX code photographed downstream in the x direction from the reading position Z. In the illustrated film carrier 22, the transport of the strips A by the transport means 50 is controlled and the strips A are pressed and released by the film crimping unit 52 in accordance with the detection result by the screen detection sensor 54.
[0025]
On the other hand, the trimming carrier 24 is a carrier for performing trimming by holding the slide B at an arbitrary position and cutting out and expanding an arbitrary position of the image of the slide B. The trimming carrier 24 holds the carrier body 66 and the base 68. And a plate 70.
[0026]
FIG. 5 shows a plan view of the carrier body 66.
The carrier body 66 is a rectangular body having the same external shape as the carrier body 46 of the film carrier 22, and grooves 42 and 44 are formed on the bottom surface corresponding to the guide rails 34 and 36.
In addition, the carrier body 66 penetrates through the light source unit.14A through-hole 72 is formed for the reading light from the light to pass therethrough.
Further, a concave portion 74 is formed on the upper surface of the carrier body 66, which is one step lower than the center of the through hole 72 and into which the base 68 is inserted and loosely fitted.
[0027]
As shown in FIG. 6, the base 68 is a plate-like member that is inserted and loosely fitted into the concave portion 74 of the carrier main body 66 and is attached to the carrier main body 66. When attached to the recess 74), a handle portion 68 a protruding from the recess 74 to the outside is formed. In addition, an input device is provided at almost the center of the base 68.10Light source14An opening 76 through which the reading light from the light passes is formed.
The base 68 has a dish-like configuration, and a mounting portion 68c is formed one step lower than the peripheral portion 68b, and the holding plate 70 is movably mounted thereon.
[0028]
The holding plate 70 is a plate-like member in which an opening 88 corresponding to the image surface of the slide B (indicated by a two-dot chain line in FIG. 6) is formed, holds the slide B, and mounts the base 68 as described above. It is movably mounted on the mounting portion 68c. Therefore, the upper surface of the holding plate 70 is formed at a height at which the film surface becomes a predetermined position in the optical axis L direction when the standard slide B is placed and placed on the placement portion 68c. The
The regulating members 78 and 78 and the contact portions 80 and 80 are fixed to the upper surface of the holding plate 70, and a pressing member 82 is attached to each regulating member 78.
In order to smoothly move the holding plate 70 on the mounting portion 68c, a lubricant such as a Teflon sheet is disposed on the back surface of the holding plate 70, the upper surface of the mounting portion 68c, or both surfaces thereof. Various lubrication treatments and the like may be applied.
[0029]
The regulating members 78 and 78 are substantially quadrangular columnar guide members that sandwich the opening 88 between the short sides and extend in the same direction as the short sides, and define the positions of the opposing end surfaces of the slide B. Therefore, the regulating member78Is set according to the slide B of the maximum size expected to be mounted.
On the other hand, the abutting portions 80 are projections arranged in the vicinity of the back end surface of the upper surface of the holding plate 70 and are regulating members.78The end surface orthogonal to the end surface to be controlled is regulated.
That is, the slide B is inserted between the regulating members 78 and 78 and is inserted in the direction of the arrow y until it comes into contact with the contact portions 80 and 80, and the position of the slide B is defined so that the entire image surface is on the opening 88. Is done.
The pressing member 82 is a regulating member that is rotatable in the vertical direction (perpendicular to the plane of FIG. 6).78The end portion on the abutting portion 80 side is urged downward so as to abut against and press against the upper surface of the holding plate 70. Accordingly, the slide B inserted between the regulating members 78 is pressed and held by the holding plate 70 by the pressing member 82.
[0030]
In the illustrated example, the slide B is placed on the holding plate 70 in a direction in which the image surface coincides with the opening 88, and the contact portions 80, 80 from the side opposite to the contact portions 80, 80. Is inserted between the regulating members 78 and 78 until it abuts against the holding plate 70 and is pressed against the holding plate 70 by the pressing member 82 and fixed.
Since the holding plate 70 is movably mounted on the mounting portion 68a of the base 68, by moving the holding plate 70 in all directions as shown by the arrows in FIG. The portion can be located on the optical axis L.
Here, as will be described in detail later, since the imaging unit 18 of the input device 10 has a zoom function, the optical axis L is the center.CCD sensor (Image sensor20)The projected image of the slide B formed on the image can be enlarged, and an arbitrary part of the image can be trimmed by adjusting the magnification by positioning the desired part of the slide B image on the optical axis L.
[0031]
The trimming carrier 24 shown in FIGS. 5 and 6 is a trimming (slide) carrier using the holding plate 70 holding the slide B, but instead of the holding plate 70, a strip as shown in FIG. A strip holding plate 85 that sandwiches the strip A and includes two plates 86 and 86 that are pivotally joined to each other by a hinge or the like in which an opening 84 corresponding to the image portion of the A is formed. By mounting this on the mounting portion 68a of the base 68, a trimming (strip) carrier for trimming an arbitrary portion of an image photographed on the strip A can be obtained.
In addition to the film carrier 22 and the trimming carrier 24, the input device 10 according to the present invention includes one manual carrier for the operator to fix the film in a predetermined position, and one slide B supplied by the operator. A slide carrier or the like that collects the slide B that has been read and completed, conveyed in the direction of arrow x, stopped at the reading position Z, used for image reading, and read may be used.
[0032]
An imaging unit 18 is disposed on the optical frame 12.
The imaging unit 18 includes a lens unit 92 that is suspended from a surface plate 90 that is fixed to the optical frame 12, a magnification adjustment motor 93, and a focus adjustment motor 94. Make an image.
The lens unit 92 includes a zoom lens unit 96 in which a known zoom lens is incorporated, and a well-known zoom lens unit 96 that adjusts the focal point of projection light on the light receiving surface of the CCD sensor 20 located above (downstream in the optical axis L direction). And a focus adjustment lens unit 98 in which a focus adjustment lens is incorporated.
[0033]
The zoom lens unit 96 changes the magnification according to the size of the film during normal reading, and is the maximum size that can receive the projection light by the CCD sensor 20 (that is, the longest part of the necessary image area is the CCD). When the image is trimmed, the magnification is changed in accordance with the setting by the operator, and the projection light is imaged on the CCD sensor 20. To do.
An adjustment gear 96a of the zoom lens unit 96 meshes with a gear 93a of a magnification adjustment motor 93 that is a pulse motor, and the zoom lens unit 96 adjusts the magnification by a magnification adjustment motor 93 controlled by the control device 102 described later. Is done. The control device 102 stores a table of magnifications according to the number of drive pulses from the origin of the zoom lens unit 96, and the control device 102 drives the magnification adjustment motor 93 according to the film size and the magnification set by the operator. Then, the magnification of the zoom lens unit 96 is adjusted by pulse control. In the illustrated example, the variable range of the magnification of the zoom lens unit 96 is 0.4 to 0.8. In this range, the magnification is adjusted in 41 steps in increments of 0.01. The step size of the magnification is not limited to this, and may be, for example, 0.001 times.
In addition, the origin of the zoom lens unit 96 may be detected by a known method such as a method using a sensor. The film size may be detected by an operator input, determination of the type of carrier mounted on the carrier base 16, or the like.
[0034]
On the other hand, the adjustment gear 98 a of the focus adjustment lens unit 98 meshes with a gear 94 a rotated by the focus adjustment motor 94, and the focus is adjusted by the focus adjustment motor 94.
The driving of the focus adjustment motor 94 is controlled by the control device 102 of the control unit 21, and the input device 10 in the illustrated example has the image contrast of the document image read by the CCD sensor 20 by the TTL (Through The Lens) method. Use for auto focus adjustment.
[0035]
The projection light of the film is imaged on the CCD sensor 20 by the lens unit 92 and is read photoelectrically. A shutter for measuring the dark current of the CCD sensor 20 is disposed between the lens unit 92 and the CCD sensor 20.
In the input device 10, the CCD sensor 20 is, for example, an area CCD sensor having 1380 × 920 pixels. Further, in the illustrated apparatus, the CCD sensor 20 is configured to be movable in the x and y directions by an amount corresponding to half a pixel, so that the number of read pixels can be apparently increased up to four times. . In the present invention, various known types of image sensors can be used in addition to the CCD sensor.
[0036]
  As described above, the sensitivity of the CCD sensor 20 with respect to each of the R, G, and B colors is not uniform, and the light from the halogen lamp 25 has a relatively large R component. Also, the negative film and the reversal film have different image color balances, and both have different R, G, and B balances.
  For this reason, when the image of the film is read under the same conditions, the output from the CCD sensor 20 differs greatly between the negative film and the reversal film and between R, G and B.
  On the other hand, in the input device 10, as a preferred embodiment, the accumulation time (electronic shutter speed) of the CCD sensor 20 in each reading of the negative film and the reversal film, and further R, G and B is changed. As described above, by changing the amount of light passing through the color filter of the color filter plate 28 for each of R, G, and B, the outputs of R, G, and B from the CCD sensor 20 in image reading are made as close as possible. As a result, the movement amount of the diaphragm 26 at the time of image reading is reduced as much as possible to secure the light amount adjustment range, improve the reading efficiency by shortening the adjustment time of the diaphragm 26, ensure the reliability of the motor 27, etc.Figureing.
[0037]
The output signal of the CCD sensor 20 is output from the image processing device 100, the control device 102, and the aperture control device 104.TheIt is sent to the control unit 21 having.
The control device 102 is a part that controls each part and the whole of the input device 10 (or digital photo printer). The control device 102 includesCCD sensor (Image sensor20), The display 106 for displaying various operation instructions such as image size read, print size setting, color / density adjustment, mode selection, etc., various settings and operation instructions according to the display 106 and predetermined procedures A keyboard 108 and a mouse 110 for operating the input device 10 are connected to constitute an operation system of the input device 10 (digital photo printer).
The control device 102 also performs focus adjustment of the lens unit 92 by the focus adjustment motor 94 and magnification adjustment of the lens unit 92 (zoom lens unit 96) by the magnification adjustment motor 93 as described above.
[0038]
The image processing apparatus 100 performs predetermined image processing such as A / D conversion and Log conversion on the output signal (image data signal) from the CCD sensor 20 during the pre-scan that roughly reads the image prior to the main scan. , Density histogram creation, setting of each image processing condition in the main scan, and the like, and an output signal from the CCD sensor 20 in the main scan for obtaining an output image is converted into A / D conversion, Log conversion, floor A predetermined process such as tone correction, shading correction, dark correction, and offset correction, color / density correction, and the like are performed and output as output image information to the image recording apparatus P or the like. This is a combination of a known image processing circuit, a memory, etc.
[0039]
The aperture control device 104 performs the illuminance setting method of the present invention, sets the aperture value of the aperture 26 in the pre-scan, and sets the aperture value of the aperture 26 in the main scan from the image information obtained by the pre-scan, The motor 27 of the light source unit 14 is driven to adjust the opening value of the diaphragm 26.
[0040]
  The aperture controller 104 adjusts the amount of reading light by the aperture 26.In other words, open value controlA light source aperture table that indicates the relationship between the opening value of the diaphragm 26 and the output from the CCD sensor 20 is stored, and the determination of the opening value of the diaphragm 26 in illuminance setting, pre-scanning, and main scanning is based on this light source. This is performed based on the aperture table.
  The light source aperture table is not particularly limited as long as it shows the relationship between the open value of the aperture 26 and the output from the CCD sensor 20, but a preferable example is a light source aperture table created as follows. Is done.
[0041]
First, since the halogen lamp 25 has a light quantity that saturates the output of the CCD sensor 20 when there is no film in the optical path, the aperture 26 is opened and the light quantity is measured by the CCD sensor 20 without the film. However, an ND filter that does not saturate the output is disposed in the optical path.
The density of the ND filter is not particularly limited, but in order to increase the S / N ratio, the output from the CCD sensor 20 with the aperture 26 opened is selected to be close to the saturation output of the CCD sensor 20. Is preferred.
[0042]
When the ND filter is arranged in the optical path, one of the color filters is inserted, the diaphragm 26 is opened, and the output C from the CCD sensor 20 is measured. Here, as described above, the motor 27 for adjusting the opening value of the diaphragm 26 is a pulse motor, and the opening value is pulse-controlled. In the illustrated input device, as an example, the control pulse when the diaphragm 26 is opened, that is, the opening value I is 500.
Output C when aperture 26 is opened₅₀₀Then, the diaphragm 26 is closed by one pulse and the output C of the CCD sensor 20 is closed.₄₉₉In the same manner, C₄₉₈, C₄₉₇, …… C₀And the output C of the CCD sensor 20 at each open value I until the aperture is closed._iMeasure.
[0043]
Next, the shutter between the CCD sensor 20 and the lens unit 92 is closed and measurement is performed to obtain the dark current D of the CCD sensor 20, and the output C at each open value is obtained as shown in the following equation._iThe dark output D is subtracted from the true output C at each open value I._IAsk for.
C_I= C_i-D (I & i = 0-500)
An example is shown in FIG. In FIG. 8, the horizontal axis is the open value I, and the vertical axis is a numerical value (C) obtained by normalizing the output (mV) from the CCD sensor 20._I).
[0044]
Output C at each open value I_IIs obtained, the output C at each open value I is given by_IOutput C when open₅₀₀Divide by to get the logarithm and output C_IOutput C when the aperture 26 is opened₅₀₀Concentration value N with reference to_IConvert to
N_I= -Log (C_I/ C₅₀₀(I = 0-500)
An example obtained by converting FIG. 8 is shown in FIG.
The graph shown in FIG. 9 shows that when the open value I is moved several times, the concentration value N_IIt is a table which shows how much fluctuates. That is, by using this table, it is understood how many pulses the aperture 26 should be opened or closed in order to make a certain density a desired density.
[0045]
Finally, the density value N of the graph shown in FIG._IIs divided into 256 equal parts to obtain the aperture standard value, and the open value I for each aperture standard value is obtained and stored in the form of a table indicating the relationship between the open value I and the standard aperture value. This table is a light source aperture table.
FIG. 10 shows an example in which the graph shown in FIG. 9 is converted. This density table shows the density value N in FIG._IIs converted into 8-bit digital density data (therefore, the vertical axis represents the density value N in FIG._IThe aperture standard value is obtained. That is, the aperture standard value corresponds to digital density data of 0 to 255, and a table indicating how many pulses the aperture 26 should be opened or closed to make certain density data desired. Become.
An example is shown in the table below.

[0046]
  The above operation is performed by sequentially inserting the R, G, and B color filters of the color filter plate 28 into the optical path L, and a light source aperture table corresponding to each of R, G, and B is created. The input device 10 uses this light source aperture table to set the illuminance, and controls the aperture value of the aperture 26 during pre-scanning and main scanning.
  This light source aperture table is a light source for reading light.A halogen lampWhen there is a change that greatly affects the characteristics of the optical system, such as when the lens 25 or the lens unit 92 is replaced, it is necessary to create a new one.
[0047]
The light source aperture table obtained in this way is created by inserting an ND filter in the optical path, and the output C when the aperture 26 is opened.₅₀₀Is a relative relationship between the open value I and the aperture standard value (that is, the output of the CCD sensor 20) with reference to, and does not necessarily indicate an absolute output (density) at a certain open value. Absent.
The image reading using the CCD sensor 20 is preferably performed so that the highest output (that is, the lowest density portion) becomes the saturation output of the CCD sensor 20 in terms of the S / N ratio. However, it is not possible to obtain an open value for obtaining a desired output only with this light source aperture table.
[0048]
Therefore, it is necessary to set the reference state of the light source unit 14, that is, the illuminance setting for image reading, in order to obtain a desired output amount of the reading light.
In other words, the illuminance setting is to set the state of the light source unit 14 so that the output of the CCD sensor 20 becomes a saturated output in the state where there is no film.
[0049]
First, the voltage applied to the halogen lamp 25 is set to a predetermined value, and further, the saturation output C of the CCD sensor 20 is set._refIs set as the target value.
Next, the open value I of the aperture 26 is adjusted to the initial aperture standard value where the output of the CCD sensor 20 is predicted to be close to saturation in the absence of film, and in this state, for example, first, the G filter of the color filter plate 28 is adjusted. 28G is inserted into the optical path L, and the output GC of the CCD sensor 20_outMeasure.
Then output GC_outIs the target value C_refThe logarithm is obtained by dividing by the above and the density value GX is calculated. That is, the density value GX is obtained by the following equation [1].
GX = -log (GC_out/ C_ref) [1]
The illuminance setting is the density value GX (ie, output GC_out) Is adjusted within a predetermined range, the state of the light source unit 14 is adjusted.
[0050]
As one of the illuminance setting methods, there is exemplified a method of adjusting the open value I of the diaphragm 26 according to the calculated density value GX so that the density value GX falls within a predetermined range (hereinafter referred to as method 1). To do).
The density value GX calculated by the equation [1] is the output GC at the open value I._outIs the target value C_refIt is a numerical value indicating how much is excessive or insufficient in terms of concentration value. Therefore, by feeding back the density value GX, GX can be brought into (close to) the target range.
That is, the first density value GX is calculated as described above, and when the value is within a predetermined range, the aperture standard value at that time is set as the open standard value GS for G image reading._setIs stored in the aperture control device 104. Output GC of the CCD sensor 20_outIs saturated, the diaphragm 26 is closed by an appropriate amount, and when the density value GX is not within the predetermined range, the above-mentioned light source diaphragm table is used for the density value GX (the corresponding aperture standard value). Minute), the aperture 26 is adjusted to the open value, the measurement is performed again, and the density value GX is calculated using the equation [1]. This operation is repeated until the density value GX enters the predetermined range, and the aperture standard value when the density value GX enters the predetermined range is set to the open standard value GS._setIs determined and stored in the aperture control device 104.
[0051]
Another method of setting the illuminance is a method of adjusting the voltage applied to the halogen lamp 25 that is a light source to bring the density value GX into the target range (hereinafter referred to as method 2).
As is well known, if the halogen lamp 25 is within a predetermined range, the applied voltage setting value can be changed without adversely affecting the halogen cycle, the color temperature, the lifetime, and the like, thereby adjusting the amount of light. be able to. This method uses this. In the above-described method 1, the voltage applied to the halogen lamp 25 is fixed to a predetermined set value.
[0052]
As described above, the first density value GX is calculated, and when the density value GX is within the predetermined range, the voltage applied to the halogen lamp 25 is fixed there, and the aperture standard value in that state is set to the open standard value. GS_setIs stored in the aperture control device 104.
Output GC of the CCD sensor 20_outWhen the voltage is saturated, the voltage applied to the halogen lamp 25 is reduced by an appropriate amount. When the concentration value GX is not within the predetermined range, the voltage applied to the halogen lamp 25 is increased by a predetermined step size. Alternatively, adjust the light quantity by reducing the output GC after the light quantity has stabilized after a certain period of time._outAnd the concentration value GX is calculated using the equation [1]. This operation is repeated until the density value GX falls within a predetermined range. When the density value GX falls within the predetermined range, the applied voltage to the halogen lamp 25 is fixed, and the aperture standard value in this state is set to the open standard value GS._setIs stored in the aperture control device 104 (thus, the aperture standard value is an initial value).
When the applied voltage to the halogen lamp 25 exceeds the adjustable range during the illuminance setting, the applied voltage to the halogen lamp 25 is fixed here, and the method 1 is used thereafter. The opening value I of the diaphragm 26 is adjusted until the density value GX falls within the predetermined range. When the density value GX falls within the predetermined range, the aperture standard value at that time is set to the open standard value GS._setIs stored in the aperture control device 104.
[0053]
In this way, the voltage applied to the halogen lamp 25 is determined, and the open standard value GS for G image reading is determined._setThen, for example, the R filter 28R of the color filter plate 28 is inserted into the optical path L, and the open standard value RS for the R image reading using only the method 1 is used._setFinally, the B filter 28B of the color filter plate 28 is inserted into the optical path L. Similarly, using the method 1 only, the open standard value BS for B image reading is used._setSet.
[0054]
In this way, the voltage applied to the halogen run 25 is determined, and the open standard value GS is determined._set, RS_setAnd BS_setTo complete the illuminance setting.
The light quantity of the halogen lamp 25 that is a light source changes over time due to deterioration, accumulation of dirt, dust, and the like. Therefore, this illuminance setting is preferably performed every time the input device 10 is started up.
In addition, since the output from the CCD sensor 20 in the creation of the light source aperture table and the illuminance setting described above cannot be obtained accurately due to the influence of shading or the like when the data of all pixels is used, the center portion, for example, FIG. If the CCD sensor 20 is a CCD sensor of 1380 × 920 pixels as shown in the example, it is preferable to use 32 × 8 pixels in the center portion and use an average value thereof.
[0055]
The open standard value is a reference for the open value of the diaphragm 26 at the time of pre-scanning. However, the input device 10 reads the image by adjusting the magnification of the zoom lens unit 96 of the lens unit 92 according to the film size and trimming. Since the amount of transmitted light varies according to the magnification of the zoom lens, the amount of projection light incident on the CCD sensor 20 varies depending on the magnification, that is, the image reading condition is affected by the magnification. Depending on the magnification, proper image reading may not be possible.
On the other hand, in the input device 10 according to the present invention, the aperture control device 104 stores a correction table (zoom light amount correction table) of the aperture 26 corresponding to the magnification of the zoom lens unit 96, and each open standard value GS._set, RS_set, BS_setIn addition, correction according to the magnification of the zoom lens unit 96 is added to set the open value of the diaphragm 26, and pre-scanning is performed. Therefore, according to the input device 10 of the present invention, it is possible to always perform proper image reading stably regardless of the magnification of the zoom lens unit 96.
[0056]
The relative amount of change in the amount of transmitted light based on the change in the effective F-number according to the change in the magnification of the zoom lens (zoom lens unit 96) can be obtained in advance by design or experiment. Accordingly, the relative light amount fluctuation of the zoom lens unit 96 according to the magnification, that is, the illuminance ratio of the projection light imaged on the CCD sensor 20 according to the magnification is designed or determined based on the magnification used for the light amount aperture table creation and illuminance setting described above This can be determined experimentally in advance.
FIG. 11 shows an example of the relationship between the magnification of the zoom lens unit 96 and the illuminance ratio. The creation of the light amount table and the illuminance setting are preferably performed at a magnification according to the film size (usually 135 size) that the input device 10 is expected to read most. The input device 10 in the illustrated example has a magnification of 0.44. Is the standard.
[0057]
Next, by performing density conversion (Log conversion) on this illuminance ratio, it is possible to obtain a density difference due to magnification change with 0.44 times as a reference. FIG. 12 shows an example of density conversion of the illuminance ratio of FIG. A table indicating the relationship between the density difference (that is, the opening value of the diaphragm 26) and the magnification is stored, and using this, density correction corresponding to the magnification of the zoom lens unit 96, that is, correction of the opening value of the diaphragm 26 is performed. By doing so, it is possible to perform image reading under certain conditions regardless of the magnification.
In the illustrated input device 10, the density difference in FIG. 12 is normalized (128 times) in the same way as the aperture standard value to obtain a corrected aperture standard value, and the magnification corresponding to each corrected aperture standard value is obtained and tabulated. The zoom light amount correction table is stored in the aperture control device 104.
[0058]
  The following table shows the zoom light quantity correction table obtained from FIG. In the table below, the magnification of the zoom lens unit is indicated as “magnification”, and the standard value of the correction aperture is indicated as “correction”. Here, as described above, when the magnification is adjusted in increments of 0.001, it is −6 up to 0.400 to 0.409 and −4 (or up to 0.410 to 0.419).Reverse. What is necessary is just to determine according to apparatus characteristics. ) Etc., the zoom light quantity correction table may be used.

[0059]
The control device 102 described above, for example, determines the film size by determining the type of the loaded carrier or input by the operator, and determines the magnification of the zoom lens unit 96 according to this, or by the operator for trimming. By the operation, the magnification adjustment motor 93 is driven to adjust the magnification.
At the same time, the magnification information is also sent to the aperture control device 104. The aperture control device 104 reads out the corrected aperture standard value corresponding to the magnification of the zoom lens unit 96 using the zoom light quantity correction table, and corrects the corrected aperture standard. Each of the aforementioned open standard values GS by adding the values_set, RS_set, BS_setThe aperture standard value obtained thereby is used as a pre-scan aperture standard value, the aperture value of the aperture 26 is determined using a light quantity aperture table, and the motor 27 is driven to adjust the aperture 26 in the pre-scan. .
As a method for discriminating the carrier type, there are known methods such as pressing a microswitch by mounting the carrier on the carrier base 16, discriminating a connector type by connecting the carrier and the input device 10, and outputting a discrimination signal from the carrier. A method is available.
[0060]
In the input device 10 according to the present invention, the opening value of the diaphragm 26 in the pre-scan is basically determined as described above. Here, in the image reading using the CCD sensor 20, it is preferable in terms of the S / N ratio that the output is saturated at the lowest density point where the transmitted light amount is maximum or in the vicinity of the maximum. When the reading is performed after the film is inserted into the optical path L, the transmitted light amount (output of the CCD sensor 20) is necessarily reduced.
Accordingly, when pre-scanning is performed, it is preferable to perform reading by increasing the amount of light by the base density of the film, that is, by opening the aperture 26. For example, the aperture standard value corresponding to the base density of the film is calculated in advance. The aperture value obtained by correcting the pre-open aperture standard value obtained from the aforementioned aperture standard value and the corrected aperture standard value corresponding to the magnification with the aperture standard value corresponding to the base density. The opening value of the diaphragm 26 may be determined based on the standard value.
[0061]
The input device 10 according to the present invention basically has the above-described configuration, and the operation thereof will be described below.
When the main power supply of the input device 10 is turned on to start the device, the above-described illuminance setting is first performed.
That is, the voltage applied to the halogen lamp 25 is set to a predetermined value and the lamp is turned on._refIs set as the target value, the opening value of the diaphragm 26 is set to the initial setting value, and when the light quantity is stabilized, the G filter 28G is inserted into the optical path L, and the output GC_outIs measured and GX is calculated.
Here, the open standard value GS for G image reading_setIf GX is not within the predetermined range, the voltage applied to the halogen lamp 25 is increased by a predetermined amount to increase the light amount, and after the light amount is stabilized, the density value GX is set. The calculation operation is repeated until the density value GX falls within a predetermined range. When the density value GX falls within the predetermined range, the applied voltage to the halogen lamp 25 is fixed, and the aperture standard value at that time is set to the open standard value GS._setIs stored in the aperture control device 104. If the concentration value GX does not fall within the predetermined range due to the voltage adjustment, the open value is further adjusted using the method 1 to set the open standard value GS._setIs set as described above.
[0062]
Next, the R filter 28R is inserted into the optical path L, and the open standard value RS according to the method 1 as described above._setSetting, that is, calculation of GX and adjustment of the opening value of the aperture 26 are repeated, and the opening standard value RS in R image reading is repeated._setIs set and stored in the aperture control device 104. Similarly, the open standard value RS in B image reading is set._setIs stored in the aperture control device 104, the applied voltage to the halogen lamp 25, the open standard value GS_set, RS_setAnd BS_setTo complete the illuminance setting.
[0063]
The operator attaches a carrier corresponding to the form of the document to be read to the carrier base 16 as shown in FIG. Here, assuming that the strip A is read, the film carrier 22 is mounted at a predetermined position on the carrier base 16 as shown in FIG.
Next, the crimping member 60 of the film crimping unit 52 is raised upward, and the strips A are loaded on the film carrier 22 so that the first image photographed on the strips A is at the reading position Z.
[0064]
On the other hand, the control device 102 of the control unit 21 determines the size of the film from the loaded carrier, determines the magnification according to the film size, drives the adjustment motor 93 to adjust the magnification of the zoom lens unit 96, At the same time, magnification information is output to the aperture controller 104.
Receiving the magnification information, the aperture control device 104 reads the corrected aperture standard value corresponding to the magnification from the zoom light quantity correction table, and opens each open standard value GS._set, RS_set, BS_setThen, the corrected aperture standard value is added, and the aperture standard value obtained thereby is used as the pre-scan aperture standard value, and the opening value of the aperture 26 in the pre-scan is determined using the light quantity aperture table.
[0065]
When an instruction to start reading is issued after the above operation is completed, automatic focus adjustment is performed as necessary, and then pre-scanning and main scanning are started.
In the prescan, for example, first, the G filter 28G is inserted into the optical path L, and the aperture controller 104 uses the light amount aperture table to change the aperture 26 opening value from the prescan aperture standard value set as described above. The motor 27 is read and the diaphragm 26 is adjusted. Light adjusted by the diaphragm 26 and the G filter 28G passes through the strips A, and the projection light carrying the image is applied to the CCD sensor 20 by the lens unit 92. An image is formed and a G image is read.
When the reading of the G image is completed, the color filter plate 28 is rotated, for example, the R filter 28R is inserted into the optical path L, and the aperture 26 is similarly adjusted in accordance with the set aperture standard value to adjust the R image. Reading is performed, and in the same manner, the B image is read and pre-scanning ends.
[0066]
The pre-scan image read by the CCD sensor 20 is sequentially sent to the image processing apparatus 100, and subjected to predetermined processing such as A / D conversion and log conversion to become image information. In addition, the obtained image is displayed on the display 106.
Further, the aperture control device 104 sequentially determines the aperture standard value in the main scan as G, R, and B in accordance with, for example, the minimum density from the density histogram created by the image processing apparatus 100.
[0067]
When the pre-scanning B image reading is completed, the G filter 28G is inserted into the optical path L again, the main scanning G image reading is subsequently started, and the aperture standard for the G scanning for the main scanning determined by the aperture controller 104 is determined. The aperture value of the aperture 26 is determined using the light source aperture table according to the value, the motor 27 is driven to adjust the aperture value of the aperture 26, and the light is adjusted by the G filter 28G and the aperture 26 in the same manner as the pre-scan. The transmitted light passes through the strips A, and the projection light is imaged on the CCD sensor 20 by the lens unit 92, and the G image of the original is read and sent to the image processing apparatus 100. And the B image are read and sent to the image processing apparatus 100.
The main scan image read by the CCD sensor 20 is subjected to predetermined processing such as A / D conversion, dark correction, and log conversion in the image processing apparatus 100 to become image information. Further, according to pre-scanning Color / density correction or the like is performed in accordance with the set processing conditions to obtain image information for output, which is output to the image recording apparatus P.
[0068]
When the first image reading is thus completed, a signal to that effect is output from the control unit 21 to the film carrier 22, the crimping member 60 rotates upward to release the strips A, and then the conveying means 50. Is driven to convey the strip A in the direction of the arrow x, and the conveyance is stopped according to the detection result by the screen detection sensor 54, and the next image is conveyed to the reading position Z.
Next, the crimping member 60 rotates downward to fix the strips A, and the pre-scan and the main scan are performed in the same manner as before.
[0069]
The image input apparatus according to the present invention has been described in detail above. However, the present invention is not limited to the above-described examples, and various modifications and improvements may be made without departing from the scope of the present invention. It is.
[0070]
【The invention's effect】
As described above in detail, the image input apparatus of the present invention adjusts the magnification by the zoom lens, reads an image obtained by trimming a desired portion from an image photographed on a film, and does not depend on the film size. Image projection can be performed by forming projection light of a size on an image sensor, and proper image reading can be performed without being affected by magnification.
[Brief description of the drawings]
FIG. 1 shows an example of an image input apparatus according to the present invention.oneIt is a schematic perspective view of a use aspect.
FIG. 2 is a schematic perspective view of a light source unit of the image input apparatus shown in FIG.
3 is a conceptual diagram showing an operation of a (variable) diaphragm of the light source unit shown in FIG.
4A and 4B are schematic perspective views showing an operation of exchanging carriers in the image input apparatus shown in FIG.
FIG. 5 is a schematic plan view of a carrier body of a trimming carrier mounted on the image input apparatus shown in FIG.
6 is a schematic plan view of a trimming carrier mounted on the image input apparatus shown in FIG. 1. FIG.
7 is a schematic perspective view of a strip holding plate used in the trimming carrier shown in FIG. 6. FIG.
FIG. 8 is a graph illustrating an example of a relationship between an open value and an output of a CCD sensor in color image reading.
FIG. 9FIG.6 is a graph in which the output of the CCD sensor in the graph shown in FIG.
FIG. 10FIG.It is the graph which normalized the density value of the graph shown by.
FIG. 11 is a graph illustrating an example of a relationship between a zoom lens magnification and an illumination ratio.
12 is a graph obtained by converting the illuminance ratio of the graph shown in FIG. 11 into a density difference.
[Explanation of symbols]
10 (Image) input device
12 Optical frame
14 Light source
16 Career base
18 Imaging unit
20 CCD sensor
21 Control unit
22 Film carrier
24 Trimming carrier
25 Light source
26 Aperture
27 Motor
28 color filter plate
30 Diffusion box
32 opening
34, 36 guide rail
38, 40, 42, 44 groove
46,66 body
48 Guide groove
50 Conveying means
52 Film crimping unit
54 Screen detection sensor
56 motor
58 Transport roller
60 Crimp member
62 axes
64 Rotating means
66 Carrier body
68 base
70 Retaining plate
72 Through hole
74 recess
76,88 opening
78 Regulatory members
80 Contact part
82 Pressing member
84 opening
85 Strips holding plate
86 Board material
90 surface plate
92 Lens unit
94 Focus adjustment motor
96 Zoom lens section
98 Focus adjustment lens
100 Image processing apparatus
102 Control device
104 Aperture control device

Claims (4)

An image input device having a pre-scan mode and a fine scan mode,
A light source unit that emits reading light emitted from a light source and adjusted in light quantity by a light source aperture;
An image sensor that photoelectrically reads the projection light transmitted through the film;
An imaging lens capable of adjusting the magnification for imaging the projection light on an image sensor;
A correction table of a light source aperture set in advance according to the magnification of the imaging lens;
An image input apparatus comprising : control means for controlling an open value of the light source aperture in the pre-scan mode by applying correction using the correction table for the light source aperture according to the magnification of the imaging lens. . The image input device according to claim 1, wherein the correction value of the open value of the light source aperture in the correction table of the light source aperture is configured to be capable of substantially continuous correction. The image input device according to claim 1, wherein the control unit standardizes an output of the image sensor for each color when the film is a color film. The light source aperture correction table sets the illuminance of the light source and / or the open value of the light source aperture so that the output from the lowest density portion of the projection light of the image sensor does not exceed the saturation output of the image sensor. The image input apparatus according to claim 1, wherein a correction value of the open value of the light source diaphragm corresponding to the magnification of the imaging lens as a reference is obtained.

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