JP3584170B2

JP3584170B2 - Print color tone change measuring device

Info

Publication number: JP3584170B2
Application number: JP31945598A
Authority: JP
Inventors: 守一広田; 智弘伊藤; 鈴木　　誠; 富和米澤
Original assignee: Hamamatsu Photonics KK; Toppan Inc
Current assignee: Hamamatsu Photonics KK; Toppan Inc
Priority date: 1998-11-10
Filing date: 1998-11-10
Publication date: 2004-11-04
Anticipated expiration: 2018-11-10
Also published as: JP2000146860A

Description

【０００１】
【発明の属する技術分野】
この発明は、移動する印刷物から絵柄の色調の変化を測定する印刷物色調変化測定装置に関係している。
【０００２】
【従来の技術】
印刷工程における印刷物の絵柄の色調の管理は印刷機の操作者が印刷された印刷物を適宜抜き取り視覚により監視しているのが大部分である。従って、基準となる印刷物の絵柄の色調からの上記抜き取られた印刷物の絵柄の色調の変化の判断は印刷機の操作者の個人的な感覚に依存しているので、印刷機の操作者が替わると完成した印刷物の絵柄の色調の変化が大きくなることがある。また近年において印刷速度が上昇する傾向の下では、印刷機の操作者が印刷物の絵柄の色調の変化を発見した時には、既に多量の不良印刷物が発生していることになる。
【０００３】
目視による印刷物の絵柄の色調の監視から生じる上述した種々の問題を解消する為に、印刷工程において印刷物の絵柄を印刷する間に印刷物の余白に色調監視用の単色または多色のカラーパッチを同時に印刷し、カラーパッチを濃度計又は測色計等のセンサで測定することにより、印刷物の絵柄の印刷直後で常時連続して印刷物の絵柄の色調の変化を監視することも行われている。
【０００４】
【発明が解決しようとする課題】
しかしながら上述した従来のセンサを使用した印刷物の絵柄の色調の変化の監視の為には、印刷物にカラーパッチを印刷する為の余白が必要である。この余白は後で印刷物から切り取る必要があるので無駄であり、近年の省資源化の傾向からは外れている。また、カラーパッチは単色または多色とはいうものの印刷物の絵柄の全ての色調を表現しているのではなく印刷物の絵柄の中の代表的な色調を表現しているだけであり、印刷物の絵柄の色調をより完璧に監視するには不足している。
【０００５】
この発明は上記事情の下でなされ、この発明の目的は、印刷物の絵柄の色調の変化の監視の為のカラーパッチの印刷が不要で印刷物の無駄をなくすことが出来、しかも印刷物の絵柄の色調を印刷物の絵柄の印刷直後で常時連続して直接監視してより完璧に監視することが出来、不良印刷物の発生を大きく減少させることが出来る印刷物色調変化測定装置を提供することである。
【０００６】
【課題を解決するための手段】
上述したこの発明の目的を達成する為に、この発明に従った印刷物色調変化測定装置は：移動する印刷物に向かい光を照射する少なくとも１つの光照射手段と；印刷物に対する上記少なくとも１つの光照射手段からの光の照射領域及び照射角度を規定する光学系と；上記照射領域において反射された反射光の可視光域の複数の波長域の強度を測定するとともに光照射手段が照射する光の可視光域の複数の波長域の強度を測定するマルチアノードフォトマルチプライヤを含み、マルチアノードフォトマルチプライヤで測定した反射光の可視光域の複数の波長域の強度を、マルチアノードフォトマルチプライヤで測定した光照射手段が照射する光の可視光域の複数の波長域の強度により補償し、補償後の反射光の可視光域の複数の波長域の強度に対応するデジタル測定信号を出力する反射光強度測定手段と；反射光強度測定手段から出力されたデジタル測定信号を受け、デジタル測定信号に基づいて印刷物における照射領域の反射率を算出し出力する反射率算出手段と；を備えており、反射率算出手段から出力される反射率の変化により印刷物の色調の変化を測定する、ことを特徴としている。
【０００７】
【作用】
このように構成されたことを特徴とする、この発明に従った印刷物色調変化測定装置においては、少なくとも１つの光照射手段により移動する印刷物に向かい光を照射し、光学系により印刷物に対する上記少なくとも１つの光照射手段からの光の照射領域及び照射角度を規定する。上記照射領域において反射された反射光の可視光域の複数の波長域の強度及び光照射手段が照射する光の可視光域の複数の波長域の強度を反射光強度測定手段がマルチアノードフォトマルチプライヤにより測定し、反射光強度測定手段はマルチアノードフォトマルチプライヤで測定した反射光の可視光域の複数の波長域の強度を、マルチアノードフォトマルチプライヤで測定した照射手段が照射する光の可視光域の複数の波長域の強度により補償し、補償後の反射光の可視光域の複数の波長域の強度に対応するデジタル測定信号を出力する。この結果として、反射光強度測定手段は印刷物における照射領域の反射光の強度を細分化して測定することが出来る。このデジタル測定信号を受け入れた反射率算出手段は、デジタル測定信号に基づいて印刷物における照射領域の反射率を細分化して算出し出力することが出来る。そして、反射率算出手段から出力される細分化された反射率の変化により印刷物の色調の変化が測定される。
上述した如く、反射光強度測定手段がマルチアノードフォトマルチプライヤで測定した反射光の可視光域の複数の波長域の強度を、マルチアノードフォトマルチプライヤで測定した光照射手段が照射する光の可視光域の複数の波長域の強度により補償し、補償後の反射光の可視光域の複数の波長域の強度に対応するデジタル測定信号を出力し、このデジタル測定信号を受け入れた反射率算出手段が、デジタル測定信号に基づいて印刷物における照射領域の反射率を算出し出力するので、反射率算出手段は照射領域の可視光域の反射光の反射率をより正確に測定することが出来、ひいてはこの反射率を基礎にした照射領域の可視光域の色調の測定をより正確に行うことが出来る。
さらにこの場合には、反射光強度測定手段がマルチアノードフォトマルチプライヤにより反射光の可視光域の複数の波長域の強度と光照射手段が照射する光の可視光域の複数の波長域の強度とを同時に測定することが好ましい。このことが反射率算出手段による照射領域の可視光域の反射光の反射率のより正確に測定、ひいてはこの反射率を基礎にした照射領域の可視光域の色調の測定のより正確な測定、をもたらす。
【０００８】
上述した如く構成されたことを特徴とする、この発明に従った印刷物色調変化測定装置においては、反射光強度測定手段が、照射領域において反射された反射光の近赤外光域の少なくとも１つの波長域の強度を測定するとともに光照射手段が照射する光の近赤外光域の少なくとも１つの波長域の強度を測定する受光素子を含んでおり、受光素子からの反射光の近赤外光域の少なくとも１つの波長域の強度を受光素子からの照射手段が照射する光の近赤外光域の少なくとも１つの波長域の強度により補償し、補償後の反射光の近赤外光域の少なくとも１つの波長域の強度に対応するデジタル測定信号を出力する、ことが好ましい。
【０００９】
このようにすることにより、反射率算出手段は上記照射領域の近赤外光域の反射光の反射率をより正確に測定することが出来、ひいてはこの反射率を基礎にした上記照射領域の近赤外光域の色調の測定をより正確に行うことが出来る。さらにこの場合には、反射光強度測定手段の受光素子が、照射領域において反射された反射光の近赤外光域の少なくとも１つの波長域の強度を測定するのと同時に光照射手段が照射する光の近赤外光域の少なくとも１つの波長域の強度を測定することがより好ましい。このことが、反射率算出手段による上記照射領域の近赤外光域の反射光の反射率のより正確な測定、ひいてはこの反射率を基礎にした上記照射領域の近赤外光域の色調のより正確な測定、をもたらす。
【００１０】
上述した如く構成されたことを特徴とする、この発明に従った印刷物色調変化測定装置においては、反射光強度測定手段が反射光の強度を測定する光の波長域は可視光域で少なくとも３つ、近赤外光域で少なくとも１つとすることが出来る。そしてこれらは同時に測定されなければならない。
【００１１】
また上述した如く構成されたことを特徴とする、この発明に従った印刷物色調変化測定装置においては、反射光強度測定手段が反射光の強度を測定する光の波長域は可視光域で少なくとも１６個、近赤外光域で少なくとも１個である、ことも出来る。当然これらは同時に測定されなければならない。
【００１２】
このように、反射光の強度を測定する光の波長域の数を増大させればさせる程、印刷物の絵柄の色調をより細かく測定することが出来る。
【００１３】
また上述した如く構成されたことを特徴とする、この発明に従った印刷物色調変化測定装置においては、反射光強度測定手段が反射光及び光照射手段が照射する光の夫々の強度を測定する光の波長域は可視光域で少なくとも１６個、近赤外光域で少なくとも１個である、ことも出来る。当然これらは同時に測定されなければならない。
【００１５】
上述した如く構成されたことを特徴とする、この発明に従った印刷物色調変化測定装置においては、光照射手段から印刷物に照射される光の入射光と印刷物から反射される反射光との間の角度、即ち光照射手段から印刷物に照射される光の印刷物に対する入射光軸と印刷物から反射される反射光の印刷物に対する反射光軸との間に創出される立体角、が４５度である、ことが好ましい。
【００１６】
この角度は、物体の反射率を光を利用して測定する場合の日本工業規格（ＪＩＳＺ８７２２号）やＣＩＥ（国際照明学会）で推奨された値である。
【００１７】
上述した如く構成されたことを特徴とする、この発明に従った印刷物色調変化測定装置においては、光学系は印刷物における光の照射領域の全域に渡り略同じ強度で光を照射させる、ことが好ましい。
【００１８】
このようであれば、反射率算出手段が照射領域の全域の反射率をより正確に測定することが出来、ひいてはこの反射率を基礎にした上記照射領域の全域の色調のより正確な測定がもたらされる。
【００１９】
上述した如く構成されたことを特徴とする、この発明に従った印刷物色調変化測定装置においては、移動距離信号を反射率算出手段に送る印刷物移動距離測定手段を備えており、反射率算出手段は印刷物移動距離測定手段からの移動距離信号を受けて照射領域の反射率を算出し出力することが出来る。
【００２０】
印刷物移動距離測定手段としては、例えばエンコーダの如き回転角センサを採用することが出来る。
【００２１】
上述した如く構成されたことを特徴とする、この発明に従った印刷物色調変化測定装置においては、相互に異なったタイミングで印刷物の移動距離に対応して移動距離信号を発生し、移動距離信号を反射率算出手段に送る複数の印刷物移動距離測定手段を備えている、ことが出来る。
【００２２】
このような構成であれば、移動距離信号をより細かな間隔で発生させることが出来、この結果として反射率算出手段が印刷物の照射領域の反射率を測定する間隔をより細かくすることが出来、ひいては、この反射率を基礎にした上記照射領域の色調のより細かな測定を可能にしている。
【００２３】
そして、現実には反射光強度測定手段は、１０μ秒乃至１０００００μ秒の範囲中のいずれかの値で反射光の強度を繰り返し測定することが出来る。
【００２４】
上述した如く構成されたことを特徴とする、この発明に従った印刷物色調変化測定装置においては、反射光強度測定手段は印刷物の夫々の絵柄について定められた所定の数の反射光の強度を測定して上記所定の数の測定信号を発生し、反射率算出手段は上記所定の数の測定信号に基づいて印刷物における照射領域の反射率を算出し出力する、ことができるし、あるいは反射率算出手段は反射光強度測定手段からの測定信号を蓄積し、蓄積された測定信号の中の所望の数の測定信号に基づいて印刷物における照射領域の反射率を算出し出力することも出来る。
【００２５】
後者の場合には、色調の変化の測定を行おうとする印刷物の種々の絵柄に応じて印刷物の絵柄の色調の変化の測定が最も効率良く正確に行われるように上記所望の数を選択することを可能にしている。
【００２６】
以下、この発明の一実施の形態に従った印刷物色調変化測定装置について添付の図面を参照しながら詳細に説明する。
【００２７】
【発明の実施の形態】
図１は、この発明の一実施の形態に従った印刷物色調変化測定装置が組み込まれた連続紙印刷機を概略的に示す側面図であり；
図２の（Ａ）は、図１の印刷物色調変化測定装置の主要部を概略的に示す図であり；
図２の（Ｂ）は、図２の（Ａ）の主要部の光照射手段において光源から光学レンズ群へと光を導く光ファイバ部材を拡大して示す斜視図であり；
図３は、印刷物に対するこの発明の一実施の形態に従った印刷物色調変化測定装置における光照射手段の光照射作用を概略的に示す側面図であり；そして、
図４は、図２の（Ａ）の主要部において印刷物からの反射光の強度を測定する反射光強度測定手段の外観を拡大して示す斜視図である。
【００２８】
図１に示された連続紙印刷機１０はオフセット連続紙印刷機であり、巻装された連続紙供給源１０ａと、連続紙供給源１０ａから所定の速度で供給された連続紙１０ｂに対してブラックＢＫ，シアンＣ，マゼンタＭ，イエローＹの４色のインキを使用して所定の同一の絵柄を所定の間隔で繰り返し印刷する印刷ユニット部１０ｃと、印刷ユニット部１０ｃにおいて同一の絵柄が所定の間隔で繰り返し印刷された後の連続紙（即ち、印刷物）１０ｂに対して所定の温度の空気を吹き付けて上記絵柄を伴った連続紙１０ｂを乾燥させる乾燥装置１０ｄと、乾燥装置１０ｄからの上記絵柄を伴った連続紙１０ｂを冷却する冷却ローラ１０ｅと、冷却ローラ１０ｅから上記絵柄を伴った連続紙１０ｂを断裁折機１１まで導く複数の搬送ローラ１０ｇと、上記絵柄を伴った連続紙１０ｂから断裁折機１１において所定の間隔で裁断され折られた同じ絵柄を伴った同じ寸法の印刷物１１ｂを連続紙印刷機１０の外部の例えば図示しない印刷物スタッカへと排出する印刷物排出装置１１ｃと、を備えている。そして、このような構成の連続紙印刷機１０は従来から広く知られている。
【００２９】
図１において連続紙印刷機１０と組み合わされて示されている、この発明の一実施の形態に従った印刷物色調変化測定装置１２は、連続紙印刷機１０において連続紙１０ｂに対して所定の間隔で繰り返し印刷された複数の同一絵柄の色調の変化を測定する為に使用されている。そして色調の変化が所定の許容の範囲を越えた場合には、印刷物色調変化測定装置１２が測定した色調の変化の程度の応じて色調の変化が小さくなるよう、手動操作または自動操作により印刷ユニット部１０ｃにおけるブラックＢＫ，シアンＣ，マゼンタＭ，イエローＹの４色のインキの為の例えばインキキーの如きインキ供給調節装置を調整する。
【００３０】
印刷物色調変化測定装置１２は、連続紙印刷機１０中における連続紙１０ｂの移動距離を測定する為の印刷物移動距離測定手段として、断裁折機１１中に配置された複数のシリンダー中で、連続紙１０ｂに所定の間隔で繰り返し印刷された多数の同一絵柄の夫々の間隔、即ち長さ、に対応して回転する１つのシリンダー１１ｄと、それ以前に配置されているもう１つの搬送ローラ１０ｇと、に連結された２つのロータリエンコーダ１４ｂ及び１４ａを備えている。２つのロータリエンコーダ１４ａ及び１４ｂの夫々は印刷物色調変化測定装置１２の制御処理ユニット１６のタイミング回路部１６ａに接続されている。
【００３１】
印刷物色調変化測定装置１２はさらに、上記もう１つの搬送ローラ１０ｇにおいて連続紙１０ｂ上に印刷された所定の間隔で繰り返し印刷された複数の同一絵柄に光を照射してその反射光の強度を測定する為の反射光強度測定ヘッド１８を備えており、反射光強度測定ヘッド１８もまた制御処理ユニット１６のタイミング回路部１６ａに接続されている。
【００３２】
制御処理ユニット１６はさらに、２つのロータリエンコーダ１４ａ及び１４ｂからの連続紙移動距離測定データや反射光強度測定ヘッド１８からの反射光強度測定データ等の種々のデータを選択的に記憶する為のメモリ回路部１６ｂと、タイミング回路部１６ａ及びメモリ回路部１６ｂの動作を指令するとともに上記種々のデータの処理をする指令・処理回路部１６ｃと、を備えており、指令・処理回路部１６ｃには制御処理ユニット１６を操作する為のパソコン１９が接続されている。
【００３３】
次には、図２の（Ａ）及び（Ｂ）を参照しながら、この発明の一実施の形態に従った印刷物色調変化測定装置１２の反射光強度測定ヘッド１８の構成について説明する。
【００３４】
反射光強度測定ヘッド１８は、図示しない光源から発生された光を上記もう１つの搬送ローラ１０ｇ上で移動する連続紙１０ｂに向かい光を照射する少なくとも１つの光照射手段２０と、上記もう１つの搬送ローラ１０ｇ上で移動する連続紙１０ｂに対する上記少なくとも１つの光照射手段２０からの光の照射領域及び照射角度を規定する光学系２２と、上記照射領域において反射された反射光の強度を測定し反射光の強度に対応するデジタル測定信号を出力する反射光強度測定手段２４と、を備えている。
【００３５】
なおこの実施の形態において反射光強度測定手段２４から出力されたデジタル測定信号を受け、デジタル測定信号に基づいて上記もう１つの搬送ローラ１０ｇ上で移動する連続紙１０ｂにおける上記照射領域中の反射率を算出し出力するのは制御処理ユニット１６の指令・処理回路部１６ｃである。
【００３６】
光学系２２についてより詳細に説明すると、光学系２２は、上記少なくとも１つの光照射手段２０からの光を連続紙１０ｂに向かい導く為の光ファイバユニット２２ａを含んでいる。図２の（Ｂ）に示されている如く光ファイバユニット２２ａは、光照射手段２０から遠ざかるにつれて全体の横断面が所定の矩形状にされている。
【００３７】
光学系２２はさらに、光ファイバユニット２２ａの矩形状の横断面を有した端に接続された矩形状の横断面を有した板状のロッドレンズ２２ｂを含んでいる。板状のロッドレンズ２２ｂは、光ファイバユニット２２ａの矩形状の横断面から出射される光の上記横断面における照度分布を実質的に均一とする。
【００３８】
光学系２２はさらにまた、ロッドレンズ２２ｂの延出端に隣接して配置された集光用レンズ群２２ｃを含んでいる。集光用レンズ群２２ｃはロッドレンズ２２ｂの大きな開口数（ＮＡ）を有する延出端において拡散する光を上記もう１つの搬送ローラ１０ｇ上で移動する連続紙１０ｂ上で所定の寸法の矩形の照射領域に集光させる。
【００３９】
矩形の照射領域の所定の寸法は、カラー印刷装置１０ｃにおけるブラックＢＫ，シアンＣ，マゼンタＭ，イエローＹの４色のインキの為の例えばインキキーの如きインキ供給調節装置の寸法に合致しており、例えば３５ｍｍ×７ｍｍである。
【００４０】
反射光強度測定手段２４についてより詳細に説明すると、反射光強度測定手段２４は、上記もう１つの搬送ローラ１０ｇ上で移動する連続紙１０ｂ上で所定の寸法の矩形の照射領域から反射された反射光を受け入れる受光光学系２４ａを含んでいる。
【００４１】
なおこの実施の形態では、光学系２２から上記照射領域に入射される入射光と上記照射領域から反射光強度測定手段２４の受光光学系２４ａに向かい反射される反射光との間の角度αが４５度に設定されているが、これはＣＩＥ（国際照明学会）や日本工業規格（ＪＩＳＺ８７２２号）で反射率を測定する時の推奨値として定められている値である。そしてこの実施の形態では、光照射手段２０や光学系２２や反射光強度測定手段２４が反射光強度測定ヘッド１８として１つのハウジング中にまとめられていることにより上記推奨値が強固に確実に保証されている。
【００４２】
受光光学系２４ａはアフォーカル系に代表される拡散光学系であり、図３に示す如く、上記もう１つの搬送ローラ１０ｇ上で移動する連続紙１０ｂ上で所定の寸法の矩形の照射領域から反射された反射光を受光光学系２４ａを介して受け取るマルチアノードフォトマルチプライヤ２４ｄの測定面で均等に拡散するようにしている。これは、上記照射領域において上記もう１つの搬送ローラ１０ｇ上で移動する連続紙１０ｂが実際には湾曲していることによる連続紙１０ｂの移動方向に沿った上記照射領域の両端部と両端部の間の中間部とで受光光学系２４ａに入射する反射光の量が異なっていることの影響を無くす為である。
【００４３】
受光光学系２４ａはハーフミラー２４ｂを有していて、ハーフミラー２４ｂで分光された上記反射光の一部は公知の例えばダイオードの如き受光素子２４ｃにより近赤外光領域（この実施の形態では９００ｎｍ乃至１３００ｎｍ）の強度が測定され、ハーフミラー２４ｂで分光された上記反射光の残りはマルチアノードフォトマルチプライヤ２４ｄにより可視光領域（この実施の形態では４００ｎｍ乃至７００ｎｍ）の複数の波長域の強度が測定される。
【００４４】
この実施の形態では、光照射手段２０が照射する光の強度の振れを原因とした反射光の上記近赤外光領域及び上記可視光領域の複数の波長域の強度の振れを補償する為に、光学系２２のロッドレンズ２２ｂから光照射手段２０が照射する光の上記近赤外光領域（この実施の形態では９００ｎｍ乃至１３００ｎｍ）の強度を測定する為のもう１つの公知の例えばダイオードの如き受光素子２４ｅへと光ファイバ２４ｆで光照射手段２０が照射する光の一部を導いているとともに、光学系２２のロッドレンズ２２ｂから光照射手段２０が照射する光の上記可視光領域（この実施の形態では４００ｎｍ乃至７００ｎｍ）の複数の波長域の強度を測定する為にマルチアノードフォトマルチプライヤ２４ｄへと光ファイバ２４ｇで光照射手段２０が照射する光のさらに一部を導いている。
【００４５】
この実施の形態で使用されるマルチアノードフォトマルチプライヤ２４ｄは、非常に広域なダイナミックレンジと高い再現性を求められていて、反射率［Ｒ］で０〜０．０１Ｒ（反射率から算出される濃度［Ｄ］で０〜２Ｄ）の領域でリニアリティを確保する為に、浜松ホトニクス社製の特願平１０−１３５５５２号に記載のマルチアノードフォトマルチプライヤを使用している。このマルチアノードフォトマルチプライヤ２４ｄは、図３に示されている如く、１個の光電子倍増管ながら複数（この実施の形態では１６個）の可視光域光強度測定用干渉フィルタ２６を介して図示されていない測定面で一度に上記複数の可視光域光強度を測定することが出来るとともに、測定した上記複数の可視光域光強度に対応する複数の測定信号を出力することが出来る。このマルチアノードフォトマルチプライヤ２４ｄはさらに、複数（この実施の形態では１６個）の光源光強度測定用干渉フィルタ２８を介して図示されていない測定面で一度に上記複数の光源光強度を測定することが出来るとともに、測定した上記複数の光源光強度に対応する複数の測定信号を出力することが出来る。
【００４６】
反射光強度測定手段２４はさらに、上記反射光の一部の上記近赤外光領域の強度を測定した受光素子２４ｃ、光学系２２のロッドレンズ２２ｂからの光照射手段２０が照射する光の上記近赤外光領域の強度を測定したもう１つの受光素子２４ｅ、そして上記反射光の残りの上記可視光域の強度を測定するとともに光学系２２のロッドレンズ２２ｂからの光照射手段２０が照射する光の上記可視光域の強度を測定するマルチアノードフォトマルチプライヤ２４ｄに接続されたサンプリング回路部３０を備えており、サンプリング回路部３０は制御処理ユニット１６の指令・処理回路部１６ｃに接続されている。
【００４７】
次には上述した如く構成されているこの発明の一実施の形態に従った印刷物色調変化測定装置の動作について説明する。
【００４８】
連続紙印刷機１０において連続紙１０ｂに連続して印刷される複数の同一絵柄の色調の変化を測定する為の指令がパソコン１９から制御処理ユニット１６の指令・処理回路部１６ｃに送られると、断裁折機１１中の１つのシリンダー１１ｄに設置されているロータリエンコーダ１４ｂは複数の同一絵柄の相互間の境界、即ち複数の同一絵柄の夫々の開始位置、に関する信号を制御処理ユニット１６のタイミング回路部１６ａに送信し、また反射光強度測定ヘッド１８に対面している搬送ローラ１０ｇに設置されているもう１つのロータリエンコーダ１４ａは複数の同一絵柄の夫々の中において連続紙１０ｂの移動方向に沿った複数の位置に関する信号を制御処理ユニット１６のタイミング回路部１６ａに送信する。
【００４９】
このように２つのロータリエンコーダ１４ａ及び１４ｂを併用することにより複数の同一絵柄の夫々の中における上記移動方向に沿った複数の位置をより精密に測定することが出来る。
【００５０】
この間に制御処理ユニット１６は、反射光強度測定ヘッド１８に対面している搬送ローラ１０ｇ上で移動する連続紙１０ｂに向かい反射光強度測定ヘッド１８の光照射手段２０に光を照射させ、この光を光学系２２により上記搬送ローラ１０ｇ上で移動する連続紙１０ｂに対して照射する際の所定の照射領域及び照射角度を規定させる。所定の照射領域において上記搬送ローラ１０ｇ上で移動する連続紙１０ｂから反射された反射光は、近赤外光域の強度が反射光強度測定手段２４のダイオード２４ｃにより測定されるとともに、同時に可視光域の上記複数の波長域の強度が反射光強度測定手段２４のマルチアノードフォトマルチプライヤ２４ｄにおいて上記複数の可視光域光強度測定用干渉フィルタ２６を介して一度に測定されている。さらに同時に、光学系２２のロッドレンズ２２ｂからの光照射手段２０が照射する光の上記近赤外光領域の強度も反射光強度測定手段２４のもう１つの受光素子２４ｅにより測定され、また可視光域の上記複数の波長域の強度が反射光強度測定手段２４のマルチアノードフォトマルチプライヤ２４ｄにおいて上記複数の光源光強度測定用干渉フィルタ２８を介して一度に測定されている。
【００５１】
そして制御処理ユニット１６の指令・処理回路部１６ｃは、パソコン１９からの指示により、反射光強度測定ヘッド１８に対面している搬送ローラ１０ｇに設置されているもう１つのロータリエンコーダ１４ａからの信号に基づいた所望のタイミングで、タイミング回路部１６ａ介し反射光強度測定ヘッド１８のサンプリング回路部３０に、マルチアノードフォトマルチプライヤ２４ｄからの上記反射光の可視光域の上記複数の波長域の強度とダイオード２４ｃからの上記反射光の近赤外光域の強度とをデジタル測定信号に変換させる。
【００５２】
さらに反射光強度測定ヘッド１８のサンプリング回路部３０は、マルチアノードフォトマルチプライヤ２４ｄからの上記反射光の可視光域の上記複数の波長域の強度とダイオード２４ｃからの上記反射光の近赤外光域の強度を基礎にして変換されたデジタル測定信号を、マルチアノードフォトマルチプライヤ２４ｄからの上記光源光の可視光域の上記複数の波長域の強度とダイオード２４ｅからの上記光源光の近赤外光域の強度とで補償した後に、補償後のデジタル測定信号を出力させる。
【００５３】
サンプリング回路部３０は算出した上記反射光の可視光域の上記複数の波長域の複数の強度及び上記反射光の近赤外光域の強度の夫々に対応するデジタル測定信号を制御処理ユニット１６の指令・処理回路部１６ｃに送り、指令・処理回路部１６ｃが上記デジタル測定信号を基礎にして上記反射光の可視光域の上記複数の波長域の複数の反射率及び上記反射光の近赤外光域の反射率を算出しパソコン１９に送る。
【００５４】
即ち、制御処理ユニット１６は上記デジタル測定信号を基礎にして上記反射光の可視光域の上記複数の波長域の複数の反射率及び上記反射光の近赤外光域の反射率を算出する反射率算出手段を構成している。
【００５５】
パソコン１９はこれらの反射率を基礎にして、反射光強度測定ヘッド１８に対面している搬送ローラ１０ｇ上で移動する連続紙１０ｂ上の複数の同一絵柄の夫々の所定の照射領域における所定の複数の地点の色調を測定する。この結果、複数の同一絵柄の夫々の所定の照射領域における所定の複数の地点の反射率に相互にずれがあれば複数の同一絵柄の間で色調の変化が生じていることになる。またパソコン１９に予め色調の基準となる上記同一絵柄の所定の照射領域における所定の複数の地点の反射率を入力しておくことにより、基準となる色調からの複数の同一絵柄の夫々の所定の照射領域における所定の複数の地点の色調の変化の客観的なずれを知ることが出来る。この色調の変化やずれは可視光域の上記複数の波長域と１つの近赤外光域とで観測され、色調の変化やずれはパソコン１９の画面に表示される。
【００５６】
連続紙印刷機１０の操作者はパソコン１９のこの画面をみて、色調の変化が所定の許容の範囲を越えた場合には、印刷物色調変化測定装置１２が測定した色調の変化の程度の応じて色調の変化が小さくなるよう、手動操作によりカラー印刷装置１０ｃにおけるシアンＣ，マゼンタＭ，イエローＹ、ブラックＢの４色のインキの為の例えばインキキーの如きインキ供給調節装置を調整することが出来るし、印刷物色調変化測定装置１２が測定した色調の変化の程度の応じて色調の変化が小さくなるようカラー印刷装置１０ｃにおけるブラックＢＫ，シアンＣ，マゼンタＭ，イエローＹの４色のインキの為の例えばインキキーの如きインキ供給調節装置を調整することを自動により行うよう構成することも出来る。
【００５７】
なお、サンプリング回路部３０から制御処理ユニット１６の指令・処理回路部１６ｃに送られた上記反射光の可視光域の上記複数の波長域の複数の強度及び上記反射光の近赤外光域の強度の夫々に対応するデジタル測定信号は、制御処理ユニット１６のメモリ回路部２３に記憶させておくことも出来る。そしてメモリ回路部２３に記憶されたデジタル測定信号は後でパソコン１９により自由に使用することが出来る。
【００５８】
またこの実施の形態では、サンプリング回路部３０における、マルチアノードフォトマルチプライヤ２４ｄからの上記反射光の可視光域の上記複数の波長域の強度と、ダイオード２４ｃからの上記反射光の近赤外光域の強度と、マルチアノードフォトマルチプライヤ２４ｄからの上記光源光の可視光域の上記複数の波長域の強度と、ダイオード２４ｅからの上記光源光の近赤外光域の強度と、の上記所望のタイミングでのサンプリングと、サンプリングし補償された後のこれらの強度のデジタル測定信号への変化と、を平行して行うことにより、上記所望のタイミングは１００μ秒で行うことが出来たが、照射光の強度を変更し、反射光強度測定ヘッド１８に対面している搬送ローラ１０ｇに設置されているロータリエンコーダ１４ａのａ／ｂ相信号の分集数を変更することにより１０μ秒と１０００００μ秒との間で自由に設定することが出来る。
【００５９】
また、このこの発明の一実施の形態に従った印刷物色調変化測定装置は、同一の絵柄を複数の枚葉紙に連続して印刷する枚葉紙印刷装置においても適用が可能である。
【００６０】
【発明の効果】
以上詳述した如く、この発明に従った印刷物色調変化測定装置によれば、印刷物の絵柄の色調の変化の監視の為のカラーパッチの印刷が不要で印刷物の無駄をなくすことが出来、しかも印刷物の絵柄の色調を印刷物の絵柄の印刷直後で常時連続して直接監視してより完璧に監視することが出来、不良印刷物の発生を大きく減少させることが出来る。
【図面の簡単な説明】
【図１】この発明の一実施の形態に従った印刷物色調変化測定装置が組み込まれた連続紙印刷機を概略的に示す側面図である。
【図２】（Ａ）は、図１の印刷物色調変化測定装置の主要部を概略的に示す図であり；（Ｂ）は、図２の（Ａ）の主要部の光照射手段において光源から光学レンズ群へと光を導く光ファイバ部材を拡大して示す斜視図である。
【図３】印刷物に対するこの発明の一実施の形態に従った印刷物色調変化測定装置における光照射手段の光照射作用を概略的に示す側面図である。
【図４】図２の（Ａ）の主要部において印刷物からの反射光の強度を測定する反射光強度測定手段の外観を拡大して示す斜視図である。
【符号の説明】
１０ｂ連続紙（印刷物）
１２制御回路手段（反射率算出手段）
１４ａ，１４ｂロータリエンコーダ（印刷物移動距離測定手段）
２０光照射手段
２２光学系
２４反射光強度測定手段
２４ｃ受光素子（近赤外域反射光強度測定手段）
２４ｄマルチアノードフォトマルチプライヤ（可視光域反射光強度測定手段：可視光域光源強度測定手段）
２４ｅ受光素子（近赤外域光源強度測定手段）[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a printed matter color tone change measuring device for measuring a change in the color tone of a picture from a moving printed matter.
[0002]
[Prior art]
Most of the management of the color tone of the picture of the printed material in the printing process is performed by the operator of the printing press extracting the printed material as appropriate and visually monitoring it. Therefore, since the judgment of the change of the color tone of the pattern of the extracted printed matter from the color tone of the pattern of the printed matter as a reference depends on the personal feeling of the operator of the printing press, the operator of the printing press changes. change in color tone of the picture of the finished printed product and may become large. In recent years, under the tendency that the printing speed is increasing, when the operator of the printing press finds a change in the color tone of the picture of the printed matter, a large amount of defective printed matter has already been generated.
[0003]
In order to solve the various problems described above resulting from the visual monitoring of the color of the picture of the printed matter, a single color patch or a multi-colored color patch for monitoring the color tone is simultaneously printed in the margin of the printed matter while printing the picture of the printed matter in the printing process. By printing and measuring a color patch with a sensor such as a densitometer or a colorimeter, a change in the color tone of the picture of the printed matter is always continuously monitored immediately after the printing of the picture of the printed matter.
[0004]
[Problems to be solved by the invention]
However, in order to monitor a change in the color tone of a picture of a printed material using the above-described conventional sensor, a margin for printing a color patch on the printed material is required. This margin is useless because it needs to be cut out from the printed matter later, and is out of the trend of resource saving in recent years. In addition, the color patch does not represent all colors of the printed pattern, although it is a single color or multicolor, but only represents a typical color tone in the printed pattern, and the printed pattern is It is insufficient to monitor the color tone more perfect is.
[0005]
The present invention has been made under the circumstances described above, and an object of the present invention is to eliminate the need for printing color patches for monitoring changes in the color tone of a picture of a printed matter, thereby eliminating waste of the printed matter, and furthermore, the color tone of the picture of the printed matter. The present invention is to provide a print color tone change measuring device capable of directly and continuously monitoring immediately after printing of a picture of a printed material to more completely monitor the printed material and greatly reducing the occurrence of defective printed materials.
[0006]
[Means for Solving the Problems]
In order to achieve the above-mentioned object of the present invention, a printed matter color tone change measuring device according to the present invention includes: at least one light irradiating means for irradiating a moving printed matter with light; and at least one light irradiating means for the printed matter. an optical system defining an irradiation area and the irradiation angle of the light from; of the reflected light reflected at the irradiation regionIncludes a multi-anode photomultiplier that measures the intensities of multiple wavelength ranges of the visible light range while measuring the intensity of multiple wavelength ranges of the visible light range, and measures with a multi-anode photomultiplier The intensity of the plurality of wavelengths in the visible light range of the reflected light is compensated by the intensity of the plurality of wavelengths in the visible light range of the light irradiated by the light irradiation means measured by the multi-anode photomultiplier. Multiple wavelength ranges of visible lightReflected light intensity measurement means for outputting a digital measurement signal corresponding to the intensity; receiving the digital measurement signal output from the reflected light intensity measurement means, calculating and outputting the reflectance of the irradiation area in the printed matter based on the digital measurement signal And a reflectance calculating means for measuring a change in the color tone of the printed matter based on a change in the reflectance output from the reflectance calculating means.
[0007]
[Action]
In the printed matter color tone change measuring device according to the present invention, which is configured as described above, the at least one light irradiating unit irradiates the moving printed matter with light, and the optical system controls the at least one of the printed matter. One of defining the irradiation area and the irradiation angle of the light from the light emitting means. Of the reflected light reflected in the irradiation areaThe reflected light intensity measuring means measures the intensity of the plurality of wavelength ranges of the visible light range and the intensity of the plurality of wavelength ranges of the visible light range of the light irradiated by the light irradiating means with a multi-anode photomultiplier,The reflected light intensity measurement meansCompensates the intensities of multiple wavelength ranges of the visible light range of the reflected light measured by the multi-anode photo multiplier by the intensities of multiple wavelength ranges of the visible light range of the light emitted by the irradiation unit measured by the multi-anode photo multiplier Of the reflected light in multiple wavelength ranges in the visible light range.Output a digital measurement signal corresponding to the intensity. As a result of this, the reflected light intensity measurement means can be measured by subdividing the intensity of the reflected light of the irradiation area on a printed material. The reflectance calculating means that has received the digital measurement signal can subdivide and calculate and output the reflectance of the irradiation area in the printed matter based on the digital measurement signal. The change in the print color is measured by the change in the subdivided reflectance is outputted from the reflectance calculating means.
As described above, the reflected light intensity measuring means measures the intensities of a plurality of wavelength ranges of the visible light range of the reflected light measured by the multi-anode photomultiplier, and the intensity of the light irradiated by the light irradiating means measured by the multi-anode photomultiplier. Means for compensating for the intensities of the plurality of wavelength ranges in the optical range, outputting digital measurement signals corresponding to the intensities of the plurality of wavelength ranges in the visible light range of the compensated reflected light, and receiving the digital measurement signals; However, since the reflectance of the irradiation area in the printed matter is calculated and output based on the digital measurement signal, the reflectance calculation means can more accurately measure the reflectance of the reflected light in the visible light range of the irradiation area, and as a result, It is possible to more accurately measure the color tone in the visible light range of the irradiation area based on the reflectance.
Furthermore, in this case, the reflected light intensity measuring means uses the multi-anode photomultiplier to measure the intensity of the reflected light in a plurality of wavelength ranges of the visible light range and the intensity of the light irradiated by the light irradiation means in the plurality of wavelength ranges of the visible light range. Are preferably measured simultaneously. This more accurately measures the reflectance of the reflected light in the visible light range of the irradiation area by the reflectance calculating means, and thus more accurately measures the measurement of the color tone of the visible light area of the irradiation area based on this reflectance, Bring.
[0008]
Characterized in that it is composed as described above, in the printed matter color change measurement device according to the invention,The reflected light intensity measuring means measures the intensity of at least one wavelength region of the near-infrared light region of the reflected light reflected in the irradiation region, and at least one of the near-infrared light regions of the light irradiated by the light irradiation device. A light-receiving element for measuring the intensity of the wavelength range, and a near-infrared light of light emitted from the light-receiving element by the irradiating means from the light-receiving element, the intensity of at least one wavelength range of the near-infrared light range of the reflected light from the light receiving element; It is preferable to compensate by the intensity of at least one wavelength region of the region, and to output a digital measurement signal corresponding to the intensity of at least one wavelength region of the near-infrared light region of the compensated reflected light.
[0009]
By doing so, the reflectance calculating means can more accurately measure the reflectance of the reflected light in the near-infrared light region of the irradiation region, and furthermore, the vicinity of the irradiation region based on this reflectance can be measured. The color tone in the infrared light range can be measured more accurately. Furthermore, in this case, the light-receiving element of the reflected light intensity measuring unit measures the intensity of at least one wavelength region of the near-infrared light region of the reflected light reflected in the irradiation region, and the light irradiation unit irradiates the light at the same time. More preferably, the intensity of at least one wavelength region in the near infrared region of the light is measured. This makes it possible to more accurately measure the reflectance of the reflected light in the near-infrared light region of the irradiation region by the reflectivity calculation means, and thus to determine the color tone of the near-infrared light region of the irradiation region based on this reflectance. More accurate measurement.
[0010]
In the printed matter color tone change measuring apparatus according to the present invention, which is configured as described above, the reflected light intensity measuring means measures at least three wavelength ranges of light in the visible light range. , At least one in the near infrared region. And these must be measured simultaneously.
[0011]
Further, in the printed matter color tone change measuring device according to the present invention, which is configured as described above, the wavelength range of the light for which the reflected light intensity measuring means measures the intensity of the reflected light is at least 16 in the visible light range. And at least one in the near infrared region. Of course, they must be measured simultaneously.
[0012]
As described above, as the number of wavelength ranges of the light for measuring the intensity of the reflected light is increased, the color tone of the picture of the printed matter can be more finely measured.
[0013]
Further, in the printed matter color tone change measuring apparatus according to the present invention, characterized in that the reflected light intensity measuring means measures the respective intensities of the reflected light and the light irradiated by the light irradiating means. May be at least 16 wavelengths in the visible light range and at least 1 wavelength in the near-infrared light range. Of course, they must be measured simultaneously.
[0015]
The print color tone change measuring device according to the present invention, characterized in that it is configured as described above, the light irradiating means between the incident light of light emitted to the printed matter from the light irradiation means and the reflected light reflected from the printed matter The angle, that is, the solid angle created between the incident optical axis of the light irradiated on the printed matter from the light irradiating means with respect to the printed matter and the reflected optical axis of the reflected light reflected from the printed matter with respect to the printed matter is 45 degrees. Is preferred.
[0016]
This angle is a value recommended by the Japanese Industrial Standard (JIS Z8722) and the CIE (International Illumination Institute) when measuring the reflectance of an object using light.
[0017]
In the printed matter color tone change measuring device according to the present invention, which is characterized in that it is configured as described above, it is preferable that the optical system emits light at substantially the same intensity over the entire light irradiation area in the printed matter. .
[0018]
In this case, the reflectance calculating means can more accurately measure the reflectance of the entire irradiation area, and thus, can provide a more accurate measurement of the color tone of the entire irradiation area based on the reflectance. It is.
[0019]
The printed matter color tone change measuring device according to the present invention, characterized in that it is configured as described above, includes a printed matter moving distance measuring unit that sends a moving distance signal to the reflectance calculating unit, and the reflectance calculating unit includes: can be receiving the moving distance signal from the printed matter moving distance measuring means calculates the reflectivity of the irradiated region output.
[0020]
The printed matter moving distance measuring means can be employed, for example, the rotation angle sensor such as an encoder.
[0021]
The printed matter color tone change measuring device according to the present invention, characterized in that it is configured as described above, generates a movement distance signal corresponding to the movement distance of the printed matter at mutually different timings, and outputs the movement distance signal. and a plurality of substrates moving distance measuring means for sending the reflectance calculating means, it is possible.
[0022]
With such a configuration, the moving distance signal can be generated at smaller intervals, and as a result, the interval at which the reflectance calculating unit measures the reflectance of the irradiation area of the printed matter can be reduced, thus, allowing a finer measurement of the color tone of the irradiation regions the reflectance basis.
[0023]
In practice, the reflected light intensity measuring means can repeatedly measure the intensity of the reflected light at any value within the range of 10 μsec to 100,000 μsec.
[0024]
In the printed matter color tone change measuring apparatus according to the present invention, the reflected light intensity measuring means measures the intensity of a predetermined number of reflected lights determined for each picture of the printed matter. And the predetermined number of measurement signals are generated, and the reflectance calculating means calculates and outputs the reflectance of the irradiation area in the printed matter based on the predetermined number of measurement signals, or calculates the reflectance. The means can also accumulate the measurement signals from the reflected light intensity measuring means, and calculate and output the reflectance of the irradiation area in the printed matter based on a desired number of the measurement signals among the accumulated measurement signals.
[0025]
In the latter case, the desired number should be selected so that the measurement of the change in the color tone of the pattern of the printed matter is most efficiently and accurately performed in accordance with the various patterns of the printed matter whose color tone change is to be measured. Is possible.
[0026]
Hereinafter, a printed matter color tone change measuring apparatus according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.
[0027]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 is a side view schematically showing a continuous paper printing press incorporating a printed matter color tone change measuring device according to an embodiment of the present invention;
(A) in FIG. 2 is an diagram showing a main part of a printed product color change measuring device of FIG. 1 schematically;
FIG. 2B is an enlarged perspective view showing an optical fiber member that guides light from the light source to the optical lens group in the light irradiation unit of the main part of FIG. 2A;
FIG. 3 is a side view schematically showing a light irradiating action of a light irradiating means in a printed matter color tone change measuring apparatus according to an embodiment of the present invention on a printed matter;
FIG. 4 is an enlarged perspective view showing the appearance of a reflected light intensity measuring means for measuring the intensity of the reflected light from the printed matter in the main part of FIG.
[0028]
The continuous paper printing machine 10 shown in FIG. 1 is an offset continuous paper printing machine. The continuous paper printing machine 10 is configured to control a continuous paper supply source 10a wound and a continuous paper 10b supplied at a predetermined speed from the continuous paper supply source 10a. A printing unit 10c that repeatedly prints the same predetermined pattern at predetermined intervals using four color inks of black BK, cyan C, magenta M, and yellow Y, and the same pattern in the printing unit 10c has a predetermined pattern. A drying device 10d that blows air at a predetermined temperature onto the continuous paper (that is, printed matter) 10b that has been repeatedly printed at intervals to dry the continuous paper 10b with the pattern, and the pattern from the drying device 10d. And a plurality of transport rollers 10g for guiding the continuous paper 10b with the pattern from the cooling roller 10e to the cutting / folding machine 11. The printed material 11b of the same size with the same pattern cut and folded at a predetermined interval in the cutting / folding machine 11 is discharged from the continuous paper 10b with the pattern to a printed material stacker (not shown) outside the continuous paper printing machine 10. and includes a print ejection device 11c which, a. Then, the continuous paper printer 10 having such a configuration are well known in the art.
[0029]
A printing material color tone change measuring device 12 according to an embodiment of the present invention, which is shown in combination with a continuous paper printing machine 10 in FIG. in is used to measure the change in color tone of the repeating printed a plurality of identical design. If the change in the color tone exceeds a predetermined allowable range, the printing unit is manually or automatically operated so that the change in the color tone is reduced according to the degree of the change in the color tone measured by the print color tone change measuring device 12. An ink supply adjusting device such as an ink key for the four color inks of black BK, cyan C, magenta M and yellow Y in the section 10c is adjusted.
[0030]
The printed material color tone change measuring device 12 includes a plurality of cylinders arranged in the cutting / folding machine 11 as a printed material moving distance measuring means for measuring a moving distance of the continuous paper 10 b in the continuous paper printing machine 10. One cylinder 11d that rotates in accordance with each interval, that is, the length, of a large number of the same pattern repeatedly printed at a predetermined interval on 10b, and another transport roller 10g that is disposed before the cylinder 11d; It includes two rotary encoder 14b and 14a connected to. Each of the two rotary encoders 14a and 14b is connected to the timing circuit 16a of the control processing unit 16 of the print color tone change measuring device 12.
[0031]
The printed matter color tone change measuring device 12 further irradiates light to a plurality of identical patterns repeatedly printed at a predetermined interval printed on the continuous paper 10b by the another transport roller 10g to measure the intensity of the reflected light. The reflected light intensity measuring head 18 is connected to the timing circuit section 16 a of the control processing unit 16.
[0032]
The control processing unit 16 further has a memory for selectively storing various data such as continuous paper moving distance measurement data from the two rotary encoders 14a and 14b and reflection light intensity measurement data from the reflection light intensity measurement head 18. A circuit section 16b, and a command / processing circuit section 16c for instructing the operation of the timing circuit section 16a and the memory circuit section 16b and for processing the various data described above. computer 19 for operating the processing unit 16 are connected.
[0033]
Next, the configuration of the reflected light intensity measuring head 18 of the printed matter color tone change measuring device 12 according to the embodiment of the present invention will be described with reference to FIGS. 2 (A) and 2 (B).
[0034]
The reflected light intensity measuring head 18 includes at least one light irradiating means 20 for irradiating light generated from a light source (not shown) toward the continuous paper 10b moving on the other transport roller 10g, An optical system 22 that defines an irradiation area and an irradiation angle of the light from the at least one light irradiation unit 20 on the continuous paper 10b moving on the transport roller 10g, and an intensity of the reflected light reflected in the irradiation area is measured. and the reflected light intensity measurement means 24 for outputting a digital measurement signal corresponding to the intensity of the reflected light, and a.
[0035]
In this embodiment, the digital measuring signal output from the reflected light intensity measuring means 24 is received, and based on the digital measuring signal, the reflectance in the irradiation area of the continuous paper 10b moving on the other conveying roller 10g is determined. is a command-processing circuit section 16c of the control processing unit 16 to calculate and output.
[0036]
Describing the optical system 22 in more detail, the optical system 22 includes an optical fiber unit 22a for guiding the light from the at least one light irradiation unit 20 toward the continuous paper 10b. As shown in FIG. 2B, the optical fiber unit 22a has a predetermined rectangular cross section as the distance from the light irradiation unit 20 increases.
[0037]
The optical system 22 further includes a plate-shaped rod lens 22b having a rectangular cross section connected to an end having a rectangular cross section of the optical fiber unit 22a. The plate-like rod lens 22b makes the illuminance distribution of the light emitted from the rectangular cross section of the optical fiber unit 22a substantially uniform in the cross section.
[0038]
The optical system 22 further includes a condenser lens group 22c arranged adjacent to the extending end of the rod lens 22b. The condensing lens group 22c irradiates the light diffused at the extended end of the rod lens 22b having a large numerical aperture (NA) into a rectangular shape having a predetermined size on the continuous paper 10b moving on the other transport roller 10g. Focus on the area.
[0039]
The predetermined size of the rectangular irradiation area matches the size of an ink supply adjusting device such as an ink key for the four color inks of black BK, cyan C, magenta M, and yellow Y in the color printing device 10c. For example, it is 35 mm × 7 mm.
[0040]
The reflected light intensity measuring means 24 will be described in more detail. The reflected light intensity measuring means 24 reflects the reflected light reflected from the rectangular irradiation area of a predetermined size on the continuous paper 10b moving on the other transport roller 10g. it includes receiving optical system 24a for receiving the light.
[0041]
In this embodiment, the angle α between the incident light that enters the irradiation area from the optical system 22 and the reflected light that is reflected from the irradiation area toward the light receiving optical system 24a of the reflected light intensity measuring unit 24 is The angle is set to 45 degrees, which is a value defined as a recommended value when measuring the reflectance according to CIE (International Illuminating Engineering Institute) or Japanese Industrial Standard (JIS Z8722). In this embodiment, the light irradiation means 20, the optical system 22, and the reflected light intensity measuring means 24 are combined in one housing as the reflected light intensity measuring head 18, so that the above-mentioned recommended values are firmly and reliably guaranteed. Have been.
[0042]
The light receiving optical system 24a is a diffusion optical system typified by an afocal system and, as shown in FIG. 3, reflects light from a rectangular irradiation area of a predetermined size on the continuous paper 10b moving on the other transport roller 10g. The reflected light is diffused evenly on the measurement surface of the multi-anode photomultiplier 24d which receives the reflected light via the light receiving optical system 24a. This is because both ends of the irradiation area and both ends of the irradiation area along the moving direction of the continuous paper 10b due to the fact that the continuous paper 10b moving on the other transport roller 10g in the irradiation area is actually curved. This is to eliminate the influence of the difference in the amount of the reflected light incident on the light receiving optical system 24a between the intermediate portion and the intermediate portion.
[0043]
The light receiving optical system 24a has a half mirror 24b, and a part of the reflected light separated by the half mirror 24b is converted into a near infrared light region (900 nm in this embodiment) by a known light receiving element 24c such as a diode. The intensity of light in the visible light range (400 nm to 700 nm in the present embodiment) is reduced by a multi-anode photomultiplier 24d for the rest of the reflected light separated by the half mirror 24b. Measured.
[0044]
In this embodiment, in order to compensate for the fluctuation of the intensity of the reflected light caused by the fluctuation of the intensity of the light irradiated by the light irradiation unit 20 in the plurality of wavelength ranges of the near-infrared light region and the visible light region. Another known diode such as a diode for measuring the intensity of the near-infrared light region (900 nm to 1300 nm in this embodiment) of the light irradiated from the rod lens 22b of the optical system 22 by the light irradiation means 20. A part of the light irradiated by the light irradiating means 20 is guided to the light receiving element 24e by the optical fiber 24f, and the visible light region of the light irradiated by the light irradiating means 20 from the rod lens 22b of the optical system 22 (this embodiment) The light irradiating means 20 irradiates the multi-anode photomultiplier 24d with the optical fiber 24g to measure the intensity in a plurality of wavelength ranges of 400 nm to 700 nm in the embodiment. In addition it has led a part of the light that.
[0045]
The multi-anode photomultiplier 24d used in this embodiment is required to have a very wide dynamic range and high reproducibility, and has a reflectance [R] of 0 to 0.01R (calculated from the reflectance). In order to secure linearity in the range of 0 to 2D in the density [D], a multi-anode photomultiplier described in Japanese Patent Application No. 10-135552 manufactured by Hamamatsu Photonics is used. As shown in FIG. 3, the multi-anode photomultiplier 24d is illustrated through a plurality of (16 in this embodiment) visible light region light intensity measuring interference filters 26 while using a single photomultiplier tube. The plurality of visible light region light intensities can be measured at once on a measurement surface that is not measured, and a plurality of measurement signals corresponding to the measured plurality of visible light region light intensities can be output. The multi-anode photomultiplier 24d further measures the plurality of light source light intensities at a time on a measurement surface (not shown) through a plurality of (16 in this embodiment) light source light intensity measuring interference filters. with it can be, it measured the plurality of source light intensity can output a plurality of measurement signals corresponding.
[0046]
The reflected light intensity measuring means 24 further includes a light receiving element 24c that measures the intensity of a part of the reflected light in the near-infrared light region, Another light-receiving element 24e that measures the intensity in the near-infrared light region, and measures the intensity of the remaining reflected light in the visible light region and irradiates the light from the rod lens 22b of the optical system 22 with the light irradiation means 20. It has a sampling circuit section 30 connected to a multi-anode photomultiplier 24d for measuring the intensity of the light in the visible light range. The sampling circuit section 30 is connected to a command / processing circuit section 16c of the control processing unit 16. I have.
[0047]
Next, the operation of the thus-configured apparatus for measuring a change in color tone of a printed material according to an embodiment of the present invention will be described.
[0048]
When a command for measuring a change in the color tone of a plurality of the same patterns continuously printed on the continuous paper 10b in the continuous paper printing machine 10 is sent from the personal computer 19 to the command / processing circuit unit 16c of the control processing unit 16, The rotary encoder 14b installed on one cylinder 11d in the cutting and folding machine 11 transmits a signal regarding a boundary between a plurality of identical pictures, that is, a start position of each of the plurality of identical pictures, to a timing circuit of the control processing unit 16. Another rotary encoder 14a which is transmitted to the unit 16a and is installed on the transport roller 10g facing the reflected light intensity measuring head 18 is provided along the moving direction of the continuous paper 10b in each of a plurality of identical patterns. transmitting a plurality of signals relating to the position and to the timing circuit portion 16a of the control processing unit 16.
[0049]
As described above, by using the two rotary encoders 14a and 14b together, it is possible to more accurately measure a plurality of positions along the moving direction in each of a plurality of the same patterns.
[0050]
During this time, the control processing unit 16 irradiates the light irradiating means 20 of the reflected light intensity measuring head 18 with light toward the continuous paper 10b moving on the transport roller 10g facing the reflected light intensity measuring head 18, and Is applied to the continuous paper 10b moving on the transport roller 10g by the optical system 22 to define a predetermined irradiation area and irradiation angle. In the reflected light reflected from the continuous paper 10b moving on the transport roller 10g in a predetermined irradiation area, the intensity in the near-infrared light range is measured by the diode 24c of the reflected light intensity measuring means 24, and at the same time, the visible light is reflected. The intensities of the plurality of wavelength ranges are measured at once by the multi-anode photomultiplier 24d of the reflected light intensity measuring means 24 through the plurality of visible light range light intensity measuring interference filters 26. At the same time, the intensity of the light irradiated by the light irradiation means 20 from the rod lens 22b of the optical system 22 in the near-infrared light region is also measured by another light receiving element 24e of the reflected light intensity measurement means 24. The intensities of the plurality of wavelength ranges are measured at once through the plurality of light source light intensity measuring interference filters 28 in the multi-anode photomultiplier 24d of the reflected light intensity measuring means 24.
[0051]
The command / processing circuit unit 16 c of the control processing unit 16 converts the signal from another rotary encoder 14 a installed on the transport roller 10 g facing the reflected light intensity measuring head 18 according to an instruction from the personal computer 19. At a desired timing based on the above, the sampling circuit unit 30 of the reflected light intensity measuring head 18 is supplied to the sampling circuit unit 30 of the reflected light intensity measuring head 18 via the timing circuit unit 16a with the intensity of the plurality of wavelength regions in the visible light region of the reflected light from the multi-anode photomultiplier 24d and the diode. and intensity of the near infrared region of the reflected light from 24c is converted into a digital measurement signal.
[0052]
Further, the sampling circuit unit 30 of the reflected light intensity measuring head 18 is configured to control the intensity of the reflected light from the multi-anode photomultiplier 24d in the plurality of wavelength ranges in the visible light range and the near-infrared light of the reflected light from the diode 24c. The digital measurement signal converted on the basis of the band intensity is converted into the near-infrared light of the light source light from the diode 24e and the intensity of the plurality of wavelength bands in the visible light region of the light source light from the multi-anode photomultiplier 24d. after compensated by the intensity of the light zone, to output a digital measurement signal after compensation.
[0053]
The sampling circuit unit 30 converts the calculated digital measurement signals corresponding to the plurality of intensities of the plurality of wavelength regions in the visible light region of the reflected light and the intensities of the near-infrared light region of the reflected light into the control processing unit 16. The command / processing circuit section 16c sends the plurality of reflectances in the plurality of wavelength ranges of the visible light range of the reflected light and the near-infrared ray of the reflected light based on the digital measurement signal. and sends it to the computer 19 calculates the reflectance of the light region.
[0054]
That is, the control processing unit 16 calculates, based on the digital measurement signal, a plurality of reflectances in the plurality of wavelength ranges in the visible light range of the reflected light and a reflectance in the near infrared light range of the reflected light. It constitutes rate calculating means.
[0055]
On the basis of these reflectances, the personal computer 19 determines a plurality of predetermined patterns in respective predetermined irradiation areas of a plurality of identical patterns on the continuous paper 10b moving on the transport roller 10g facing the reflected light intensity measuring head 18. Measure the color tone at the point. As a result, if the reflectances of a plurality of predetermined points in the respective predetermined irradiation areas of the plurality of identical patterns are mutually shifted, a change in color tone occurs between the plurality of identical patterns. Further, by inputting in advance the reflectance of a plurality of predetermined points in a predetermined irradiation area of the same picture as a reference of the color tone to the personal computer 19, each of the plurality of predetermined pictures of the same picture from the reference color tone is inputted. it is possible to know the objective deviation of the change in color tone of a predetermined plurality of points in the irradiated region. This change or shift in color tone is observed in the plurality of wavelength ranges in the visible light range and one near infrared light range, and the change or shift in color tone is displayed on the screen of the personal computer 19.
[0056]
The operator of the continuous paper printing machine 10 looks at this screen of the personal computer 19, and if the change in color tone exceeds a predetermined allowable range, the operator changes the color tone measured by the print color tone change measuring device 12 according to the degree of color change. The ink supply adjusting device such as an ink key for the four color inks of cyan C, magenta M, yellow Y, and black B in the color printing device 10c can be adjusted by manual operation so that the change in color tone becomes small. For example, for the four color inks of black BK, cyan C, magenta M, and yellow Y in the color printing device 10c, the change in the color tone is reduced according to the degree of the color tone change measured by the color tone change measurement device 12 in the printed matter. It may also be configured to perform the automatic adjusting the such ink supply adjusting device ink keys.
[0057]
The plurality of intensities of the plurality of wavelength ranges in the visible light range of the reflected light and the near-infrared light range of the reflected light transmitted from the sampling circuit unit 30 to the command / processing circuit unit 16c of the control processing unit 16 are described. digital measurement signals corresponding to the respective intensities can also be stored in the memory circuit 23 of the control processing unit 16. The digital measuring signals stored in the memory circuit 23 can be freely used by later computer 19.
[0058]
In this embodiment, in the sampling circuit section 30, the intensity of the reflected light from the multi-anode photomultiplier 24d in the plurality of wavelength ranges in the visible light range, and the near-infrared light of the reflected light from the diode 24c. And the intensity of the plurality of wavelength ranges of the visible light region of the light source light from the multi-anode photomultiplier 24d and the intensity of the near-infrared light region of the light source light from the diode 24e. The above-mentioned desired timing could be performed in 100 μsec by performing the sampling at the timing described above and the change of these intensities to the digital measurement signal after being sampled and compensated in parallel. The intensity of light is changed, and a / a of the rotary encoder 14a installed on the transport roller 10g facing the reflected light intensity measurement head 18 It can be set freely between the 10μ seconds and 100000μ seconds by changing the partial collection of the number of the phase signal.
[0059]
Further, the print color tone change measuring apparatus according to the embodiment of the present invention can be applied to a sheet printing apparatus for continuously printing the same pattern on a plurality of sheets.
[0060]
【The invention's effect】
As described in detail above, according to the printed color change measurement device according to the invention, can be of color patches for the monitoring of the color tone of the printed matter of the picture change printing eliminate the waste of unnecessary printed material, moreover printed matter The color tone of the pattern can be directly and continuously monitored immediately after the pattern of the printed matter is continuously and directly monitored, so that the occurrence of defective printed matter can be greatly reduced.
[Brief description of the drawings]
FIG. 1 is a side view schematically showing a continuous paper printing machine incorporating a printed matter color tone change measuring device according to an embodiment of the present invention.
2A is a diagram schematically showing a main part of the color tone change measuring device of FIG. 1; FIG. 2B is a diagram showing a main part of FIG. It is a perspective view which expands and shows the optical fiber member which guides light to an optical lens group.
FIG. 3 is a side view schematically showing a light irradiating action of a light irradiating means in a printed matter color tone change measuring device according to one embodiment of the present invention for a printed matter.
4 is an enlarged perspective view showing the appearance of reflected light intensity measuring means for measuring the intensity of reflected light from a printed matter in the main part of FIG. 2A.
[Explanation of symbols]
10b continuous paper (printed matter)
12 control circuit means (reflectance calculating means)
14a, 14b Rotary encoder (printed material moving distance measuring means)
20 light irradiating means
22 optical system
24 reflected light intensity measurement means
24c light receiving element (near-infrared region reflected light intensity measuring means)
24d multi-anode photomultiplier (visible light range reflected light intensity measuring means: visible light range light source intensity measuring means)
24e light receiving element (near infrared light source intensity measuring means)

Claims

At least one light irradiation means for irradiating toward light in printed matter moving;
An optical system defining an irradiation area and the irradiation angle of the light from the at least one light irradiation means for the printed matter;
A multi-anode photomultiplier that measures the intensities of a plurality of wavelength ranges of the visible light region of the light reflected by the irradiation region and measures the intensities of the plurality of wavelength regions of the visible light region of the light irradiated by the light irradiation unit. The intensity of a plurality of wavelength ranges of the visible light range of the reflected light measured by the multi-anode photomultiplier, the plurality of wavelength ranges of the visible light range of the light irradiated by the light irradiation means measured by the multi-anode photomultiplier. compensated by the intensity of the reflected light intensity measuring means for outputting a digital measurement signal corresponding to the intensity of the plurality of wavelength regions in the visible light region of the reflected light after compensation;
Reflectance calculating means for receiving the digital measurement signal output from the reflected light intensity measuring means, calculating and outputting the reflectance of the irradiation area in the printed matter based on the digital measurement signal;
A print color tone change measuring device, comprising: measuring a change in the color tone of the printed material based on a change in the reflectance output from the reflectance calculating means.

The reflected light intensity measuring means measures the intensity of at least one wavelength region of the near-infrared light region of the reflected light reflected in the irradiation region, and at least one of the near-infrared light regions of the light irradiated by the light irradiation device. A light-receiving element for measuring the intensity of the wavelength range; and a near-infrared light of the light emitted from the light-receiving means by the light irradiating means from the light-receiving element. The method according to claim 1, further comprising: compensating for the intensity of at least one wavelength region of the light region, and outputting a digital measurement signal corresponding to the intensity of at least one wavelength region of the near-infrared light region of the reflected light after the compensation. The printed matter color tone change measuring device according to claim 1.

3. The method according to claim 2, wherein the reflected light intensity measuring means measures at least three wavelength ranges of light in a visible light range and at least one wavelength range in a near-infrared range, and measures these at the same time. 2. The printed matter color tone change measuring device according to 1.

Wavelength range of the light reflected light intensity measuring means for measuring the intensity of the reflected light is at least 16 in the visible light region, at least one in the near infrared region, claim 2 these are measured at the same time, it is characterized by 2. The printed matter color tone change measuring device according to 1.

The reflected light intensity measuring means measures the intensity of each of the reflected light and the light irradiated by the light irradiating means. The wavelength range of the light is at least 16 in the visible light range and at least one in the near infrared range, and these are measured simultaneously. to, prints color change measuring device according to claim 2, characterized in that.

The angle between the reflected light reflected from the incident light and the printed material of the light irradiated to the printed material from the light emitting means is 45 degrees, to any one of claims 1 to 5, characterized in A printed matter color tone change measuring device as described in the above.

Optics substantially over the entire area of the irradiation region of light in the printed matter is irradiated with light with the same intensity, prints color change measuring device according to any one of claims 1 to 6, characterized in that.

In response to the movement distance of the printed matter to generate the moving distance signals, a moving distance signal includes a print moving distance measuring means for sending the reflectance calculating means, the moving distance signal from the reflectance calculating means prints moving distance measuring means The print color tone change measuring apparatus according to any one of claims 1 to 7, wherein the apparatus receives and receives and calculates and outputs the reflectance of the irradiation area.

Corresponding to the moving distance of the printed material at different timings from each other a moving distance signal generated by the movement distance signal and a plurality of substrates moving distance measuring means for sending the reflectance calculating means, and wherein the claim 9. The color tone change measuring device for printed matter according to 8.

Printed matter according to any one of claims 1 to 9 reflected light intensity measurement means for repeatedly measuring the intensity of the reflected light at any value in the range of 10μ seconds to 100000μ seconds, characterized in that Color tone change measuring device.

The reflected light intensity measurement means measures the intensity of the reflected light of a predetermined number defined for the pattern of each of the printed matter to generate a measurement signal of the predetermined number, the reflectance calculating means said predetermined number of measurement signals The print color tone change measuring device according to any one of claims 1 to 10, wherein the reflectance of an irradiation area in the print is calculated and output based on the following formula.

Reflectance calculating means accumulates the measurement signals from the reflected light intensity measurement means, calculates and outputs the reflectivity of the irradiated area on a printed material based on the desired number of measurement signals in the accumulated measurement signal, that The printed matter color tone change measuring device according to any one of claims 1 to 11, characterized in that: