JP3847197B2

JP3847197B2 - Spectroscopic analyzer

Info

Publication number: JP3847197B2
Application number: JP2002088524A
Authority: JP
Inventors: 憲一石見; 真一河端
Original assignee: Kubota Corp
Current assignee: Kubota Corp
Priority date: 2002-03-27
Filing date: 2002-03-27
Publication date: 2006-11-15
Anticipated expiration: 2022-03-27
Also published as: JP2003287496A

Description

【０００１】
【発明の属する技術分野】
本発明は、計測対象箇所に位置する被計測物に光を照射する投光手段と、前記被計測物からの透過光を受光して分光し、その分光された光を計測する受光手段と、各部の動作を制御する制御手段とが設けられ、前記制御手段が、前記受光手段にて受光した光により、前記被計測物の内部品質を解析するように構成されている分光分析装置に関する。
【０００５】
【課題を解決するための手段】
〔請求項１記載の発明〕
請求項１に記載の発明は、計測対象箇所に位置する被計測物に光を照射する投光手段と、前記被計測物からの透過光を受光して分光し、その分光された光を計測する受光手段と、各部の動作を制御する制御手段とが設けられ、
前記制御手段が、前記受光手段にて受光した光により、前記被計測物の内部品質を解析するように構成されている分光分析装置であって、
前記被計測物が前記計測対象箇所を通過するように設定速度で搬送コンベアにて搬送されるように構成され、
前記投光手段と前記受光手段とが、前記計測対象箇所の左右両側箇所に振り分けて配置され、
前記受光手段の位置を前記計測対象箇所に対して遠近方向に沿って変更調節する間隔維持手段が設けられ、
前記制御手段が、前記被計測物の品種が変わる際に予め入力される被計測物の大きさについての品種情報及び制御プログラムに基づいて、前記計測対象箇所に位置することになる被計測物のうちで推測される最も大きい被計測物と前記受光手段との間隔を設定間隔に維持するように、前記間隔維持手段の変更調節動作を制御するように構成されている点を特徴とする。
【０００８】
〔請求項２記載の発明〕
請求項２に記載の発明は、請求項１記載の発明において、前記計測対象箇所に位置する前記被計測物と前記投光手段との間隔を変更調節できるように、前記投光手段の位置を前記計測対象箇所に対して遠近方向に沿って変更調節する投光位置調整手段が設けられ、
前記制御手段が、前記被計測物の品種が変わる際に予め入力される被計測物の大きさについての品種情報及び制御プログラムに基づいて、前記投光手段から照射される集束光の焦点位置が、前記計測対象箇所に位置することになる被計測物のうちで推測される最も小さい被計測物の表面と一致するように、前記投光位置調整手段の変更調節動作を制御するように構成されている点を特徴とする。
【００２４】
【発明の実施の形態】
以下、本発明に係る分光分析装置用のデータ処理装置について、被計測物Ｍとして例えばミカンの内部品質情報（糖度や酸度等）を計測するための分光分析装置に対する処理に適用した場合について図面に基づいて説明する。
【００２５】
先ず、前記分光分析装置の構成並びに計測動作について説明する。
図１に示すように、分光分析装置は、被計測物Ｍに光を照射する投光部１と、被計測物Ｍを透過した光を計測対象光として、その計測対象光を分光してその分光した計測対象光を受光して分光スペクトルデータを得る受光部２と、分光スペクトルデータに基づいて被計測物Ｍの内部品質を解析する演算処理や、各部の動作を制御する動作制御処理等を実行する制御部３等を備えて構成され、被計測物Ｍは、搬送コンベア６により設定速度で一列で縦列状に載置搬送されて計測対象箇所Ｔを順次、通過していくように構成されている。そして、計測対象箇所Ｔに位置する被計測物Ｍに対して、投光部１から投射した光が被計測物Ｍを透過した後に受光部２にて受光される状態で、投光部１と受光部２とが、計測対象箇所Ｔの左右両側箇所に振り分けて配置されている。
【００２６】
前記投光部１には、計測対象箇所Ｔに対して遠近方向に移動自在に構成されて、計測対象箇所Ｔに位置する被計測物Ｍに光を照射する投光手段７が備えられ、前記受光部２には、計測対象箇所Ｔに対して遠近方向に移動自在に構成されて、被計測物Ｍからの透過光を受光して分光し、その分光された光を計測する受光手段８が備えられている。
さらに、投光部１には、投光位置調整手段４として、軸受１１ａに回転自在に支持されて計測対象箇所Ｔに対して遠近方向に沿って設けられたネジ棒１２ａと、そのネジ棒１２ａの一端側に連結されて制御部３によって制御されるパルスモータ１３ａと、ネジ棒１２ａに外嵌するナット部材１４ａとが備えられ、投光手段７は、前記ナット部材１４ａを備える架台１５ａの上方に取り付けられている。そして、制御部３がパルスモータを回転させることによって、投光手段７の位置が、計測対象箇所Ｔに対して遠近方向に沿って変更調節されて、計測対象箇所Ｔに位置する被計測物Ｍと前記投光手段７との間隔を変更調節できるように構成されている。
同様に、前記受光部２においても、間隔維持手段５として、軸受け１１ｂ、ネジ棒１２ｂ、パルスモータ１３ｂ、及びナット部材１４ｂとが備えられ、受光手段８は、ナット部材１４ｂを備えた架台１５ｂの上方に取り付けられている。そして、受光手段８の位置が、計測対象箇所Ｔに対して遠近方向に沿って変更調節されて、計測対象箇所Ｔに位置する被計測物Ｍと受光手段８との間隔を設定間隔に維持するように構成されている。
【００２７】
次に、前記投光手段７の構成について説明する。
前記投光手段７は、図２に示すように、投光用枠体２８の内部に、ハロゲンランプからなる光源２１、この光源２１から発光する光を反射させて被計測物Ｍの表面に焦点を合わせるための凹面形状の光反射板２２、この光反射板２２にて集光される光の焦点位置近くに位置させて、小径の透過孔を通過させることで集光された後の光の径方向外方側への広がりを抑制する絞り手段としての絞り板２３、光源２１からの光が計測対象箇所Ｔに照射される状態と、光を遮断する状態とに切り換え自在な投光用シャッター機構２４、集光された光源２１からの光を並行光に変更させる投光用コリメータレンズ２５、並行光に変化した光を反射して計測対象箇所Ｔに位置する被計測物Ｍに向けて横向きに変更する投光用反射鏡２６、この投光用反射鏡２６にて反射された光を集光させる投光用集光レンズ２７とを備えて構成されている。
また、前記投光用シャッター機構２４は、詳述はしないが、遮蔽板を電動モータを用いた操作機構によって揺動操作して、光が計測対象箇所Ｔに照射される状態と、光を遮断する状態とに切り換える構成となっている。
【００２８】
前記受光手段８は、図３に示すように、受光用枠体２９の内部に、被計測物Ｍを透過した計測対象光を集光する受光用集光レンズ３１、この受光用集光レンズ３１を通過してくる光のうち後述するような計測対象の波長領域（６００ｎｍ〜１０００ｎｍ）の範囲の光だけを計測対象光として上向きに反射し、それ以外の波長の光をそのまま通過させるバンドパスミラー３２、このバンドパスミラー３２により上向きに反射された計測対象光をそのまま通過させる開放状態と、前記計測対象光の通過を阻止する遮蔽状態とに切り換え自在な受光用シャッター機構３３、開放状態の受光用シャッター機構３３を通過した光が入射されると、その光を分光して前記分光スペクトルデータを計測する分光器３４、バンドパスミラー３２をそのまま直進状態で通過した光の光量を検出する光量検出センサ３５等を備えて構成されている。
【００２９】
前記分光器３４は、図４に示すように、入光口３６から入射した計測対象光を反射する受光用反射鏡３７と、反射された計測対象光を複数の波長の光に分光する凹面回折格子３８と、凹面回折格子３８によって分光された計測対象光における各波長毎の光強度を検出することにより分光スペクトルデータを計測する受光センサ３９とが、外部からの光を遮光する遮光性材料からなる暗箱４０内に配置される構成となっている。この受光センサ３９は、凹面回折格子３８にて分光反射された光を同時に各波長毎に受光するとともに波長毎の信号に変換して出力する、１０２４ビットのＭＯＳ型ラインセンサにて構成されている。このラインセンサは、詳述はしないが、各単位画素毎にフォトダイオード等の光電変換素子と、その光電変換素子にて得られた電荷を蓄積するコンデンサ、及び、その蓄積電荷を外部に出力させるための駆動回路等を内装して構成されている。
尚、コンデンサによる電荷蓄積時間は、外部から駆動回路を介して変更させることができるようになっている。
【００３０】
前記受光用シャッター機構３３は、図５に示すように、放射状に複数のスリット４１が形成された円板４２を、シャッター用パルスモータ４３によって縦軸芯周りで回転操作される状態で備えて構成され、前記暗箱４０の入光口３６には前記各スリット４１が上下に重なると光を通過させる開放状態となり、スリット４１の位置がずれると光を遮断する遮断状態となるように、スリット４１とほぼ同じ形状の透過孔４４が形成されており、光の漏洩がないように暗箱４０の入光口３６に対して円板４２を密接状態で摺動する状態で配備して構成されている。すなわち、この受光用シャッター機構３３は凹面回折格子３８に対する入光口３６に近接する状態で設けられている。
【００３１】
前記投光手段７及び前記受光手段８は、上述したように、計測対象箇所Ｔに対して遠近方向に沿って夫々の位置が変更調節されるように構成されているとともに、被計測物Ｍが通過する計測対象箇所Ｔの上方側を迂回するように設けられた枠体５５によって一体的に支持される状態で設けられ、この枠体５５は、上下調節機構６１によって搬送コンベア６に対してその全体の上下方向の位置を変更調節することができるようになっている。上下調節機構６１については、詳述はしないが、固定部６２に対して位置固定状態で設置され、上下位置調節用電動モータ６３にて駆動されるネジ送り機構６４によって上下に移動させることができるようになっている。
そして、搬送コンベア６における被計測物Ｍの通過箇所の上方側に位置させて、固定部６２にて位置固定される状態で基準体の一例であるリファレンスフィルター６５が設けられている。このリファレンスフィルター６５は、所定の吸光度特性を有する光学フィルターで構成され、具体的には、オパールガラスを用いて構成されている。
【００３２】
そして、前記枠体５５の全体を上下方向に位置調節することによって、図７（イ）に示すように、投光手段７からの光が搬送コンベア６に載置される被計測物Ｍを透過した後に受光手段８にて受光される通常計測状態と、図７（ロ）に示すように、各投光手段７からの光が前記リファレンスフィルター６５を透過した後に受光手段８にて受光されるリファレンス計測状態とに切り換えることができるように構成されている。
【００３３】
前記搬送コンベア６は無端回動チェーン６ａに設定間隔をあけて被計測物Ｍ載置用のバケット６ｂを取付けて回動駆動する構成となっており、図６に示すように、搬送コンベア６による計測対象箇所Ｔの搬送方向上手側箇所には、前記バケット６ｂの中心位置が通過する毎に検出信号を出力する光学式の通過センサ４５が備えられている。すなわち、この通過センサ４５は、被計測物Ｍが計測対象箇所Ｔを通過する周期を検出する搬送周期検出手段として機能することになる。
【００３４】
前記制御部３は、マイクロコンピュータを利用して構成してあり、図９に示すように、分光器３４によって得られる分光スペクトルデータに基づいて被計測物Ｍの内部品質を解析する演算手段１００や、各部の動作を制御する制御手段としての動作制御手段１０１が夫々制御プログラム形式で備えられる構成となっている。
つまり、上述したような、投光位置調整手段４の変更調節動作、間隔維持手段５の変更調節動作、各シャッター機構２４、３３の開閉動作、上下調節機構６１の動作、及び、受光センサ３９の動作の管理等の各部の動作を制御するとともに、後述するような公知技術である分光分析手法を用いて被計測物Ｍの内部品質を解析する演算処理を実行する構成となっている。
【００３５】
そして、制御部３は、予め入力される被計測物Ｍの大きさについての品種情報に基づいて、被計測物Ｍの大きさが小さい品種の場合には、図８の（イ）に示す如く、上下調節機構６１を操作して、被計測物Ｍ中央部分を中心として被計測物Ｍの全体にわたって均一に投光手段７からの光が照射されるように、投光手段７と受光手段８との上下方向の位置を調整するとともに、制御部３が投光位置調整手段４のパルスモータ１３ａを回転させて、投光手段７から照射される集束光の焦点位置を、計測対象箇所Ｔに位置する推測される最も小さい被計測物Ｍの表面と一致するように、投光手段７の位置を計測対象箇所Ｔに近づける方向へ変更調節し、間隔維持手段５のパルスモータ１３ｂを回転させて、計測対象箇所Ｔに位置する推測される最も大きい被計測物Ｍと受光手段８との間隔を設定間隔に維持するように、受光手段８の位置を計測対象箇所Ｔに近づける方向へ変更調節する。また、被計測物Ｍの大きさが大きい品種の場合にも、図８の（ロ）に示すように、上下調節機構６１にて投光手段７と受光手段８とを上方側に移動させ、被計測物Ｍの中央部分を中心として被計測物Ｍの全体にわたって投光手段７からの光が照射されるように調整するとともに、制御部３が投光位置調整手段４のパルスモータ１３ａを回転させて、投光手段７から照射される集束光の焦点位置が、計測対象箇所Ｔに位置する推測される最も小さい被計測物Ｍの表面と一致するように、投光手段７の位置を計測対象箇所Ｔから遠ざかる方向へ変更調節し、間隔維持手段５のパルスモータ１３ｂを回転させて、計測対象箇所Ｔに位置する推測される最も大きい被計測物Ｍと受光手段８との間隔を設定間隔に維持するように、受光手段８の位置を計測対象箇所Ｔから遠ざかる方向へ変更調節する。
【００３６】
つまり、投光手段７からの光が、被計測物Ｍの中央部分を中心として、被計測物Ｍの全体にわたって均一に照射され、且つ、被計測物Ｍを通過せずに被計測物Ｍを回り込んで分光器３４へ入射することを抑制されるべく、投光手段７と受光手段８との上下方向の位置を調整するとともに、投光手段７と被計測物Ｍとの間隔、及び、被計測物Ｍと受光手段８との間隔を調整することによって、投光手段７から照射される光を集束する状態で的確に被計測物Ｍへ入射させて、受光手段８にて設定適正量となる受光量が得られるようにすることとなり、受光センサ３９の電荷蓄積量が不足してＳ／Ｎ（信号対雑音）比が低下してしまうことを防止しながら、外乱光が被計測物Ｍを透過した検出光に混じって受光手段８に入射することを防止して、受光量が設定適正範囲を逸脱して受光センサ３９の電荷蓄積量が飽和しまうことを防止できるように構成されているものである。
【００３７】
なお、予め入力する計測条件については、被計測物Ｍの品種や大きさが変わる際に、搬送コンベア６に被計測物Ｍを載置させる前に制御部３に入力したり、搬送コンベア６にて被計測物Ｍを計測対象箇所Ｔに搬送する途中で計測条件を検出して、その検出された計測条件を制御部３に入力するようにしている。
【００３８】
次に、動作制御手段１０１による制御動作について説明する。
動作制御手段１０１は、被計測物Ｍに対する通常の計測に先立って、投光手段７からの光を被計測物Ｍに代えて前記リファレンスフィルター６５に照射して、そのリファレンスフィルター６５からの透過光を、分光器３４にて分光してその分光した光を受光して得られた分光スペクトルデータを光量基準分光スペクトルデータとして求める基準データ計測モードと、搬送コンベア６により搬送される被計測物Ｍに対して、投光手段７から光を照射して計測分光スペクトルデータを得て、この計測分光スペクトルデータと前記光量基準分光スペクトルデータとに基づいて、被計測物Ｍの内部品質を解析する通常データ計測モードとに切り換え自在に構成されている。
【００３９】
詳述すると、前記基準データ計測モードにおいては、搬送コンベア６による被計測物Ｍの搬送を停止させている状態で、前記校正用データ計測状態に切り換える。そして、前記受光用シャッター機構３３を開放状態に切り換えて、投光手段７からの光を被計測物Ｍに代えて前記リファレンスフィルター６５に照射して、そのリファレンスフィルター６５からの透過光を、分光器３４にて分光してその分光した光を受光して得られた分光スペクトルデータを基準分光スペクトルデータとして計測する。
【００４０】
そして、前記基準データ計測モードにおいては、分光器３４への光が遮断された無光状態での受光センサ３９の検出値（暗電流データ）も計測される。すなわち、前記分光器３４の受光用シャッター機構３３を遮蔽状態に切り換えて、そのときの受光センサ３９の単位画素毎における検出値を暗電流データとして求めるようにしている。
【００４１】
次に、通常データ計測モードにおける制御動作について説明する。
この通常データ計測モードにおいては、上下調節機構６１を操作して枠体５５を通常計測状態に切り換えて、搬送コンベア６による被計測物Ｍの搬送を行う。そして、前記通過センサ４５による検出情報に基づいて、被計測物Ｍが計測対象箇所Ｔを通過する周期を検出し、その周期に同期させる状態で、分光した光を受光して電荷蓄積動作を設定時間実行する電荷蓄積処理と、蓄積した電荷を送り出す送出処理とを設定周期で繰り返すように、受光センサ３９の動作を制御する。つまり、図１０に示すように、各被計測物Ｍが計測対象箇所Ｔを通過すると予測される時間帯において、受光センサ３９が設定時間Ｔ１だけ電荷蓄積処理を実行し、被計測物Ｍが計測対象箇所Ｔに存在しないと予測される各被計測物Ｍ同士の中間位置付近が計測対象箇所Ｔに位置するようなタイミングで、設定時間Ｔ２だけ、蓄積した電荷を送り出す送出処理を実行するように、受光センサ３９の動作を制御する。従って、この計測装置では、受光センサ３９による電荷蓄積時間は常に一定で動作する構成となっている。尚、１秒間に７個づつ被計測物Ｍが通過するような処理能力とした場合には、電荷蓄積処理を実行する設定時間Ｔ１は、約１４０ｍｓｅｃ程度になる。
【００４２】
そして、動作制御手段１０１は、受光センサ３９が前記電荷蓄積処理を行う状態において、受光センサ３９が電荷蓄積処理を行う状態において、遮蔽状態から開放状態に切り換えてその開放状態を開放維持時間Ｔｘが経過する間維持した後に遮蔽状態に戻すように、受光用シャッター機構３３の動作を制御するよう構成され、変更指令情報に基づいて、前記開放維持時間Ｔｘを変更調整するように構成されている。
この開放維持時間Ｔｘは、被計測物Ｍの品種の違いに応じて変更させる構成となっている。説明を加えると、例えば、温州ミカンであれは光が比較的透過しやすいので比較的短い時間（１０ｍｓｅｃ程度）に設定し、伊予柑であれば光が透過し難いので長めの時間（３０ｍｓｅｃ程度）に設定する。
このような品種の違いによる動作条件の設定は、作業員が人為的に行う構成となっている。つまり、図９に示すように、品種の違いに応じて設定位置を人為的に切り換える人為操作式の切換操作具６６が設けられ、この切換操作具６６の設定情報が制御部３に入力され、制御部３はその設定情報に従って開放維持時間Ｔｘを変更調整する構成となっている。
【００４３】
又、動作制御手段１０１は、前記光量検出センサ３５にて検出される受光量、すなわち、被計測物Ｍの光透過量の実測値の変化に基づいて、被計測物Ｍが計測対象箇所Ｔに到達したか否かを検出するようになっており、被計測物Ｍが到達したことを検出すると受光用シャッター機構３３を開放状態に切り換え、前記開放維持時間Ｔｘだけ開放状態を維持した後に、受光用シャッター機構３３を遮蔽状態に切り換えて計測処理を終了する構成となっている。
具体的に説明すると、図１１に光量検出センサ３５の検出値の時間経過に伴う変化状態を示している。被計測物Ｍが到達するまでは投光手段７から投射される光によってほぼ最大値が出力されているが、被計測物Ｍが計測対象箇所Ｔに至ると計測用光が遮られて光量検出センサ３５の検出値（受光量）が減少し始めて検出値が予め設定した設定値以下にまで減少したとき（ｔ１）に、被計測物Ｍが計測対象箇所Ｔに到達したものと判断して、その時点から設定時間が経過したとき（ｔ２）に、受光用シャッター機構３３を開放状態に切り換える。そして、前記開放維持時間Ｔｘだけ開放状態を維持した後に、受光用シャッター機構３３を遮蔽状態に切り換えるのである。
【００４４】
そして、前記演算手段１００は、このようにして得られた各種データに基づいて公知技術である分光分析手法を用いて被計測物Ｍの内部品質を解析する演算処理を実行するように構成されている。
つまり、上記したようにして得られた計測分光スペクトルデータを、前記基準データ計測モードにて求められた基準分光スペクトルデータ、及び、暗電流データを用いた正規化して、分光された各波長毎の吸光度スペクトルデータを得るとともに、その吸光度スペクトルデータの二次微分値を求める。そして、その二次微分値により被計測物Ｍに含まれる糖度に対応する成分量や酸度に対応する成分量を算出する解析演算処理を実行するように構成されている。
吸光度スペクトルデータｄは、基準分光スペクトルデータをＲｄ、計測分光スペクトルデータをＳｄとし、暗電流データをＤａとすると、
【００４５】
【数１】
ｄ＝ｌｏｇ｛（Ｒｄ−Ｄａ）／（Ｓｄ−Ｄａ）｝
【００４６】
という演算式にて求められる。
そして、制御部３は、このようにして得られた吸光度スペクトルデータｄを二次微分した値のうち特定波長の値と、下記の数２に示される検量式とを用いて、被計測物Ｍに含まれる成分量を算出するのである。
【００４７】
【数２】
Ｙ＝Ｋ０＋Ｋ１・Ａ（λ１）＋Ｋ２・Ａ（λ２）
【００４８】
但し、
Ｙ；成分量
Ｋ０，Ｋ１，Ｋ２；係数
Ａ（λ1 ），Ａ（λ2 ）；特定波長λにおける吸光度スペクトルの二次微分値
【００４９】
尚、成分量を算出する成分毎に、特定の成分量算出式、特定の係数Ｋ０，Ｋ１，Ｋ２、及び、波長λ１，λ２等が予め設定されて記憶されており、演算手段１００は、この成分毎に特定の検量式を用いて、各成分の成分量を算出する構成となっている。
【００５３】
〔別実施形態〕
次に別実施形態を説明する。
（１）上記実施形態では、投光手段として、ハロゲンランプ、反射板、及び、投光用反射鏡を備える構成としたが、これに限定されるものではない。
例えば、光源に水銀灯、Ｎｅ放電管等を用いたものでもよく、また、ビーム光による照射範囲を変更自在なビーム光源を投光手段として用いてもよい。
【００５４】
（２）上記実施形態では、上下調節機構として、分光分析装置を上下方向へ移動させて、計測対象箇所に対する投光手段及び受光手段の上下方向位置を変更調整するような構成としたが、これに限定されるものではない。
例えば、搬送手段を上下方向へ移動させて、計測対象箇所に対する投光手段及び受光手段の上下方向位置を変更調整するような構成としてもよく、また、搬送手段におけるバケット部だけを、上下方向へ移動できるような構成として、計測対象箇所に対する投光手段及び受光手段の上下方向位置を変更調整するような構成としてもよい。
【００５５】
（３）上記実施形態では、被計測物の内部品質として、糖度や酸度を例示したが、これに限らず、食味の情報等、それ以外の内部品質を計測してもよい。
【００５６】
（４）上記実施形態では、基準体としてオパールガラスによるフィルターを用いたが、これに限らず、例えば、スリガラスなどの拡散板の他、所定の吸光度特性を有するものであればよく、材質は限定されない。
また、受光手段もＭＯＳ型ラインセンサに限らず、ＣＣＤ型ラインセンサなどの他の検出手段を用いるようにしてもよい。
【図面の簡単な説明】
【図１】分光分析装置の概略構成図
【図２】投光手段の構成図
【図３】受光手段の構成図
【図４】分光器の構成図
【図５】シャッター機構を示す図
【図６】通過センサの設置状態を示す平面図
【図７】上下位置変更状態を示す図
【図８】異なる大きさの被計測物に対する投光手段及び受光手段の位置調節状態を示す図
【図９】制御ブロック図
【図１０】計測作動のタイミングチャート
【図１１】受光量の変化と計測タイミングを示す図
【符号の説明】
３制御手段
４投光位置調整手段
５間隔維持手段
６搬送コンベア
７投光手段
８受光手段
Ｍ被計測物
Ｔ計測対象箇所[0001]
BACKGROUND OF THE INVENTION
The present invention comprises a light projecting means for irradiating light to a measurement object located at a measurement target location, a light receiving means for receiving and splitting the transmitted light from the measurement object, and measuring the dispersed light, The present invention relates to a spectroscopic analyzer that includes a control unit that controls operations of the respective units, and that the control unit analyzes an internal quality of the object to be measured by light received by the light receiving unit.
[0005]
[Means for Solving the Problems]
[Invention of Claim 1]
According to the first aspect of the present invention, the light projecting means for irradiating the object to be measured located at the measurement target location, the transmitted light from the object to be measured is received and dispersed, and the dispersed light is measured. A light receiving means for controlling, and a control means for controlling the operation of each part,
The control means is a spectroscopic analyzer configured to analyze the internal quality of the object to be measured by the light received by the light receiving means,
The object to be measured is configured to be conveyed on a conveyor at a set speed so as to pass through the measurement target location,
The light projecting means and the light receiving means are arranged separately on the left and right sides of the measurement target location,
An interval maintaining means for changing and adjusting the position of the light receiving means along the perspective direction with respect to the measurement target location is provided,
Based on the product information and the control program about the size of the measurement object inputted in advance when the product of the measurement object changes, the control means of the measurement object to be located at the measurement target location It is characterized in that the change adjustment operation of the interval maintaining means is controlled so that the interval between the largest object to be measured and the light receiving means is maintained at a set interval .
[0008]
[Invention of Claim 2]
According to a second aspect of the present invention, in the first aspect of the present invention, the position of the light projecting unit is adjusted so that the distance between the object to be measured and the light projecting unit located at the measurement target location can be changed and adjusted. A light projection position adjusting means for changing and adjusting the measurement target location along the perspective direction is provided,
Based on the product information about the size of the object to be measured and the control program input in advance when the product of the object to be measured changes, the control means determines the focal position of the focused light emitted from the light projecting means. The change adjustment operation of the light projection position adjusting means is controlled so as to coincide with the surface of the smallest object to be estimated among the objects to be measured that are to be located at the measurement target location. It is characterized by that.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the data processing apparatus for a spectroscopic analysis apparatus according to the present invention is applied to a process for a spectroscopic analysis apparatus for measuring, for example, internal quality information (sugar content, acidity, etc.) of a mandarin orange as a measurement object M in the drawings. This will be explained based on.
[0025]
First, the configuration and measurement operation of the spectroscopic analyzer will be described.
As shown in FIG. 1, the spectroscopic analysis device includes a light projecting unit 1 that irradiates light to the measurement object M, and the light that has passed through the measurement object M as measurement target light. A light receiving unit 2 that receives spectral measurement target light and obtains spectral spectrum data, an arithmetic process that analyzes the internal quality of the measurement object M based on the spectral spectrum data, and an operation control process that controls the operation of each unit. The measurement object M is configured to include the control unit 3 and the like to be executed, and is configured such that the object to be measured M is placed and conveyed in a single line in a row at a set speed by the conveyor 6 and sequentially passes through the measurement target portion T. ing. And with respect to the to-be-measured object M located in the measurement target location T, the light projected from the light projecting unit 1 is transmitted through the to-be-measured object M, and then received by the light receiving unit 2. The light receiving unit 2 is arranged so as to be distributed to both the left and right side portions of the measurement target portion T.
[0026]
The light projecting unit 1 includes a light projecting means 7 configured to be movable in a perspective direction with respect to the measurement target location T and irradiating light to the measurement object M located at the measurement target location T. The light receiving unit 2 includes a light receiving unit 8 configured to be movable in the perspective direction with respect to the measurement target location T, receiving and spectrally transmitting the transmitted light from the measurement target M, and measuring the split light. Is provided.
Further, in the light projecting unit 1, as the light projecting position adjusting means 4, a screw rod 12a rotatably supported by the bearing 11a and provided along the perspective direction with respect to the measurement target location T, and the screw rod 12a. A pulse motor 13a that is connected to one end of the motor and controlled by the control unit 3, and a nut member 14a that fits externally on the screw rod 12a. The light projecting means 7 is located above the gantry 15a that includes the nut member 14a. Is attached. Then, when the control unit 3 rotates the pulse motor, the position of the light projecting means 7 is changed and adjusted along the perspective direction with respect to the measurement target location T, and the measurement object M located at the measurement target location T. And the light projecting means 7 can be changed and adjusted.
Similarly, the light receiving section 2 also includes a bearing 11b, a screw rod 12b, a pulse motor 13b, and a nut member 14b as the interval maintaining means 5, and the light receiving means 8 includes a base 15b having a nut member 14b. It is attached above. Then, the position of the light receiving means 8 is changed and adjusted along the perspective direction with respect to the measurement target location T, and the interval between the measurement object M located at the measurement target location T and the light receiving means 8 is maintained at the set interval. It is configured as follows.
[0027]
Next, the configuration of the light projecting means 7 will be described.
As shown in FIG. 2, the light projecting means 7 reflects a light source 21 composed of a halogen lamp inside a light projecting frame 28 and a light emitted from the light source 21 to focus on the surface of the object M to be measured. A concave-shaped light reflecting plate 22 for matching the light, and the light after being condensed by passing through a small-diameter transmission hole positioned near the focal position of the light condensed by the light reflecting plate 22 A diaphragm plate 23 serving as a diaphragm means for suppressing spread outward in the radial direction, a light projection shutter that can be switched between a state in which light from the light source 21 is irradiated on the measurement target location T and a state in which the light is blocked. The mechanism 24, a collimating lens 25 for projecting light that changes the condensed light from the light source 21 into parallel light, and sideways toward the object M to be measured positioned at the measurement target location T by reflecting the light that has changed into parallel light. Projection reflector 26 to be changed to, and this projection mirror It is constituted by a light projecting condenser lens 27 for condensing the reflected light at 6.
Although not described in detail, the light projecting shutter mechanism 24 swings the shielding plate by an operating mechanism using an electric motor to block the light from being irradiated on the measurement target portion T. It is the structure which switches to the state to perform.
[0028]
As shown in FIG. 3, the light receiving unit 8 includes a light receiving condensing lens 31 that condenses measurement target light that has passed through the measurement object M, and a light receiving condensing lens 31. A bandpass mirror that reflects upward only the light in the wavelength range (600 nm to 1000 nm) of the measurement target as will be described later, and passes the light of other wavelengths as it is. 32. A light-receiving shutter mechanism 33 that can be switched between an open state in which the measurement target light reflected upward by the band-pass mirror 32 is allowed to pass through and a shielding state in which the measurement target light is prevented from passing through. When light that has passed through the shutter mechanism 33 is incident, the light travels straight through the spectroscope 34 and the bandpass mirror 32 that measure the spectral data by dispersing the light. It is configured to include a light-power detection sensor 35 for detecting the amount of light passing through in state.
[0029]
As shown in FIG. 4, the spectroscope 34 includes a light receiving reflecting mirror 37 that reflects the measurement target light incident from the light entrance 36, and concave diffraction that splits the reflected measurement target light into light of a plurality of wavelengths. The light receiving sensor 39 that measures spectral spectrum data by detecting the light intensity for each wavelength in the measurement target light spectrally separated by the concave diffraction grating 38 includes a light shielding material that shields light from the outside. It becomes the structure arrange | positioned in the dark box 40 which becomes. The light receiving sensor 39 is composed of a 1024-bit MOS type line sensor that simultaneously receives the light spectrally reflected by the concave diffraction grating 38 for each wavelength and converts it into a signal for each wavelength and outputs it. . Although not described in detail, this line sensor outputs a photoelectric conversion element such as a photodiode for each unit pixel, a capacitor for accumulating the charge obtained by the photoelectric conversion element, and the accumulated charge to the outside. The drive circuit for this is built in.
The charge accumulation time by the capacitor can be changed from the outside via a drive circuit.
[0030]
As shown in FIG. 5, the light receiving shutter mechanism 33 includes a disk 42 in which a plurality of slits 41 are radially formed in a state of being rotated around a vertical axis by a shutter pulse motor 43. When the slits 41 overlap with each other in the light entrance 36 of the dark box 40, the slit 41 is in an open state where light is allowed to pass therethrough, and when the position of the slit 41 is shifted, the slit 41 is blocked. A transmission hole 44 having substantially the same shape is formed, and the disk 42 is arranged so as to slide in close contact with the light entrance 36 of the dark box 40 so as not to leak light. That is, the light receiving shutter mechanism 33 is provided in the state of being close to the light entrance 36 for the concave diffraction grating 38.
[0031]
As described above, the light projecting unit 7 and the light receiving unit 8 are configured such that their positions are changed and adjusted along the perspective direction with respect to the measurement target location T, and the object M to be measured is The frame body 55 is provided in a state of being integrally supported by a frame body 55 provided so as to bypass the upper side of the passing measurement target location T. The overall vertical position can be changed and adjusted. Although not described in detail, the vertical adjustment mechanism 61 can be moved up and down by a screw feed mechanism 64 that is installed in a fixed position with respect to the fixing portion 62 and driven by an electric motor 63 for vertical position adjustment. It is like that.
And the reference filter 65 which is an example of a reference | standard body is provided in the state fixed to the upper side of the passage location of the to-be-measured object M in the conveyance conveyor 6, and the position fixed by the fixing | fixed part 62. The reference filter 65 is composed of an optical filter having a predetermined absorbance characteristic, and specifically is composed of opal glass.
[0032]
Then, by adjusting the position of the entire frame 55 in the vertical direction, the light from the light projecting means 7 is transmitted through the measurement object M placed on the conveyor 6 as shown in FIG. And the normal measurement state in which the light is received by the light receiving means 8, and the light from each light projecting means 7 is received by the light receiving means 8 after passing through the reference filter 65 as shown in FIG. It can be switched to the reference measurement state.
[0033]
The transport conveyor 6 is configured to be rotationally driven by attaching a bucket 6b for placing an object to be measured M at a set interval to an endless rotating chain 6a. As shown in FIG. An optical passage sensor 45 that outputs a detection signal every time the central position of the bucket 6b passes is provided at a location on the upper side in the transport direction of the measurement target location T. That is, the passage sensor 45 functions as a conveyance cycle detection unit that detects a cycle in which the measurement object M passes through the measurement target portion T.
[0034]
The control unit 3 is configured by using a microcomputer. As shown in FIG. 9, the control unit 3 analyzes the internal quality of the measurement object M based on the spectral data obtained by the spectroscope 34. The operation control means 101 as a control means for controlling the operation of each part is provided in a control program format.
That is, as described above, the change adjustment operation of the light projection position adjusting unit 4, the change adjustment operation of the interval maintaining unit 5, the opening / closing operation of each shutter mechanism 24, 33, the operation of the vertical adjustment mechanism 61, and the light receiving sensor 39 While controlling the operation | movement of each part, such as management of operation | movement, it becomes the structure which performs the arithmetic processing which analyzes the internal quality of the to-be-measured object M using the spectral analysis method which is a well-known technique which is mentioned later.
[0035]
Then, based on the product information about the size of the measurement object M input in advance, the control unit 3 determines that the measurement object M has a small size as shown in FIG. The light projecting means 7 and the light receiving means 8 are operated by operating the vertical adjustment mechanism 61 so that the light from the light projecting means 7 is irradiated uniformly over the entire object to be measured M around the center portion of the object to be measured M. And the control unit 3 rotates the pulse motor 13a of the light projecting position adjusting unit 4 so that the focal position of the focused light emitted from the light projecting unit 7 is set to the measurement target location T. The position of the light projecting means 7 is changed and adjusted so as to approach the measurement target location T so as to coincide with the surface of the smallest estimated object M to be measured, and the pulse motor 13b of the interval maintaining means 5 is rotated. , The most presumed to be located at the measurement target point T So as to maintain the distance between the listening object to be measured M and the light-receiving unit 8 to set the interval, to adjust changes in the direction to approach the position of the light receiving unit 8 to the measurement target portions T. Further, even in the case of a product with a large size of the object M to be measured, as shown in FIG. 8B, the vertical adjustment mechanism 61 moves the light projecting means 7 and the light receiving means 8 upward, While adjusting so that the light from the light projecting means 7 is irradiated to the whole of the measured object M around the central portion of the measured object M, the control unit 3 rotates the pulse motor 13a of the light projecting position adjusting means 4. Thus, the position of the light projecting means 7 is measured so that the focal position of the focused light emitted from the light projecting means 7 coincides with the surface of the smallest object M to be estimated located at the measurement target location T. The distance between the target object T and the light receiving means 8 is adjusted by changing and adjusting the direction away from the target part T, and the pulse motor 13b of the interval maintaining means 5 is rotated to set the distance between the largest object M to be measured and the light receiving means 8 located at the measurement target part T So that the position of the light receiving means 8 is To adjust changes in the direction away from the target point T.
[0036]
That is, the light from the light projecting means 7 is irradiated uniformly over the entire measurement object M around the central portion of the measurement object M, and the measurement object M is not passed through the measurement object M. The vertical position of the light projecting means 7 and the light receiving means 8 is adjusted in order to prevent the light from entering and entering the spectroscope 34, and the distance between the light projecting means 7 and the measurement object M, and By adjusting the distance between the measured object M and the light receiving means 8, the light irradiated from the light projecting means 7 is accurately incident on the measured object M in a focused state, and the light receiving means 8 sets an appropriate amount. As a result, the ambient light can be measured while preventing the charge accumulation amount of the light receiving sensor 39 from being insufficient and the S / N (signal to noise) ratio from being lowered. M is prevented from entering the light receiving means 8 mixed with the detection light transmitted through M, and In which the charge accumulation amount of the light receiving sensor 39 amount deviates from the set appropriate range is configured to prevent the put away saturation.
[0037]
Note that the measurement conditions to be input in advance may be input to the control unit 3 before placing the measurement object M on the transfer conveyor 6 or the transfer conveyor 6 when the type or size of the measurement object M changes. Then, the measurement condition is detected in the middle of conveying the measurement object M to the measurement target location T, and the detected measurement condition is input to the control unit 3.
[0038]
Next, a control operation by the operation control unit 101 will be described.
Prior to normal measurement of the measurement object M, the operation control means 101 irradiates the reference filter 65 with light from the light projecting means 7 instead of the measurement object M, and transmits light from the reference filter 65. Is measured by the spectroscope 34, and the spectral data obtained by receiving the spectrally separated light is obtained as a reference data measurement mode for obtaining the light quantity reference spectral data, and the measurement object M conveyed by the conveyor 6. On the other hand, normal data for irradiating light from the light projecting means 7 to obtain measured spectral data and analyzing the internal quality of the measurement object M based on the measured spectral data and the light quantity reference spectral data. It can be switched to the measurement mode.
[0039]
More specifically, in the reference data measurement mode, the calibration data measurement state is switched to a state in which the conveyance of the object M to be measured by the conveyor 6 is stopped. Then, the light receiving shutter mechanism 33 is switched to the open state, the light from the light projecting means 7 is irradiated to the reference filter 65 in place of the measurement object M, and the transmitted light from the reference filter 65 is spectrally separated. Spectral data obtained by spectroscopically receiving the dispersed light by the instrument 34 is measured as reference spectral data.
[0040]
In the reference data measurement mode, the detection value (dark current data) of the light receiving sensor 39 in the non-light state where the light to the spectroscope 34 is blocked is also measured. That is, the light receiving shutter mechanism 33 of the spectroscope 34 is switched to the shielding state, and the detection value for each unit pixel of the light receiving sensor 39 at that time is obtained as dark current data.
[0041]
Next, the control operation in the normal data measurement mode will be described.
In this normal data measurement mode, the vertical adjustment mechanism 61 is operated to switch the frame 55 to the normal measurement state, and the object to be measured M is conveyed by the conveyor 6. Then, based on the detection information from the passage sensor 45, the period during which the measurement object M passes through the measurement target location T is detected, and in the state synchronized with the period, the dispersed light is received and the charge accumulation operation is set. The operation of the light receiving sensor 39 is controlled so that the charge accumulation process executed for a time and the sending process for sending out the accumulated charge are repeated at a set cycle. That is, as shown in FIG. 10, in the time zone in which each measurement object M is predicted to pass through the measurement target location T, the light receiving sensor 39 executes the charge accumulation process for the set time T1, and the measurement object M measures. The sending process for sending out the accumulated charges for the set time T2 is executed at a timing such that the vicinity of the intermediate position between the measured objects M that are predicted not to exist in the target place T is located at the measurement target place T. The operation of the light receiving sensor 39 is controlled. Therefore, this measuring apparatus is configured to operate with the charge accumulation time by the light receiving sensor 39 always being constant. If the processing capability is such that seven objects to be measured M pass every second, the set time T1 for executing the charge accumulation processing is about 140 msec.
[0042]
Then, the operation control means 101 switches the open state from the shield state to the open state when the light receiving sensor 39 performs the charge accumulation process and the light reception sensor 39 performs the charge accumulation process. It is configured to control the operation of the light receiving shutter mechanism 33 so as to return to the shielding state after being maintained for a while, and is configured to change and adjust the opening maintaining time Tx based on change command information.
This open maintenance time Tx is configured to be changed according to the type of the object to be measured M. For example, in Satsuma mandarin, light is relatively easy to transmit, so it is set to a relatively short time (about 10 msec). For Iyokan, it is difficult to transmit light, so a long time (about 30 msec) Set to.
The setting of the operation condition depending on the kind of the product is configured to be manually performed by an operator. That is, as shown in FIG. 9, there is provided an artificial operation type switching operation tool 66 for artificially switching the setting position according to the type of product, and setting information of the switching operation tool 66 is input to the control unit 3. The control unit 3 is configured to change and adjust the opening maintenance time Tx according to the setting information.
[0043]
Further, the operation control means 101 detects the measured object M at the measurement target location T based on the change in the measured amount of light received by the light quantity detection sensor 35, that is, the light transmission amount of the measured object M. Whether or not the object to be measured M has arrived is detected, the light-receiving shutter mechanism 33 is switched to the open state, and the light-receiving shutter mechanism 33 is kept open for the open maintaining time Tx. The measurement shutter mechanism 33 is switched to the shielding state and the measurement process is terminated.
More specifically, FIG. 11 shows a change state of the detection value of the light amount detection sensor 35 over time. The maximum value is output by the light projected from the light projecting means 7 until the measurement object M arrives. However, when the measurement object M reaches the measurement target location T, the measurement light is blocked and the light amount is detected. When the detection value (the amount of received light) of the sensor 35 starts to decrease and the detection value decreases to a preset value or less (t1), it is determined that the measurement object M has reached the measurement target location T, When the set time has elapsed from that point (t2), the light receiving shutter mechanism 33 is switched to the open state. Then, after maintaining the open state for the open maintaining time Tx, the light receiving shutter mechanism 33 is switched to the shielded state.
[0044]
And the said calculating means 100 is comprised so that the calculation process which analyzes the internal quality of the to-be-measured object M using the spectral analysis method which is a well-known technique based on the various data obtained in this way may be performed. Yes.
That is, the measured spectral spectrum data obtained as described above is normalized using the reference spectral spectrum data obtained in the reference data measurement mode and the dark current data, and is obtained for each wavelength that is spectrally separated. Absorbance spectrum data is obtained, and a second derivative value of the absorbance spectrum data is obtained. And it is comprised so that the analytical calculation process which calculates the component amount corresponding to the sugar content contained in the to-be-measured object M and the component amount corresponding to acidity by the secondary differential value may be performed.
The absorbance spectrum data d is Rd as the reference spectrum data, Sd as the measured spectrum data, and Da as the dark current data.
[0045]
[Expression 1]
d = log {(Rd−Da) / (Sd−Da)}
[0046]
It is calculated by the following formula.
And the control part 3 uses the value of a specific wavelength among the values which carried out the secondary differentiation of the absorbance spectrum data d obtained in this way, and the measurement object M using the calibration formula shown by the following formula 2. The amount of components contained in is calculated.
[0047]
[Expression 2]
Y = K0 + K1 · A (λ1) + K2 · A (λ2)
[0048]
However,
Y: component amounts K0, K1, K2; coefficients A (λ1), A (λ2); second derivative of absorbance spectrum at specific wavelength λ
For each component for calculating the component amount, a specific component amount calculation formula, specific coefficients K0, K1, K2, wavelengths λ1, λ2, and the like are preset and stored. The component amount of each component is calculated using a specific calibration formula for each component.
[0053]
[Another embodiment]
Next, another embodiment will be described.
(1) In the above-described embodiment, the light projecting unit includes the halogen lamp, the reflector, and the light reflecting reflector. However, the present invention is not limited to this.
For example, a mercury lamp, a Ne discharge tube, or the like may be used as the light source, or a beam light source that can change the irradiation range by the beam light may be used as the light projecting means.
[0054]
(2) In the above embodiment, the vertical adjustment mechanism is configured such that the spectroscopic analyzer is moved in the vertical direction to change and adjust the vertical position of the light projecting means and the light receiving means with respect to the measurement target location. It is not limited to.
For example, the conveying unit may be moved in the vertical direction to change and adjust the vertical positions of the light projecting unit and the light receiving unit with respect to the measurement target location, and only the bucket portion of the conveying unit is moved in the vertical direction. As a configuration that can be moved, a configuration that changes and adjusts the vertical position of the light projecting unit and the light receiving unit with respect to the measurement target portion may be used.
[0055]
(3) In the said embodiment, although sugar content and acidity were illustrated as internal quality of a to-be-measured object, not only this but internal quality other than that, such as taste information, may be measured.
[0056]
(4) In the above embodiment, a filter made of opal glass is used as a reference body. However, the present invention is not limited to this, and for example, a material having a predetermined absorbance characteristic may be used in addition to a diffusion plate such as ground glass. Not.
The light receiving means is not limited to the MOS type line sensor, and other detection means such as a CCD type line sensor may be used.
[Brief description of the drawings]
1 is a schematic configuration diagram of a spectroscopic analyzer. FIG. 2 is a configuration diagram of a light projecting means. FIG. 3 is a configuration diagram of a light receiving means. FIG. 4 is a configuration diagram of a spectrometer. 6] Plan view showing the installation state of the passage sensor. [FIG. 7] FIG. 8 is a view showing the state of changing the vertical position. [FIG. 8] FIG. ] Control block diagram [Fig. 10] Timing chart of measurement operation [Fig. 11] Diagram showing change in received light amount and measurement timing [Explanation of symbols]
3 Control means 4 Projection position adjustment means 5 Spacing maintenance means
6 Conveyor 7 Light projecting means 8 Light receiving means M Object T Measurement target location

Claims

The light projecting means for irradiating the object to be measured located at the measurement target location, the light receiving means for receiving and splitting the transmitted light from the object to be measured and measuring the dispersed light, and the operation of each part Control means for controlling,
The control means is a spectroscopic analyzer configured to analyze the internal quality of the object to be measured by the light received by the light receiving means,
The object to be measured is configured to be conveyed on a conveyor at a set speed so as to pass through the measurement target location,
The light projecting means and the light receiving means are arranged separately on the left and right sides of the measurement target location,
An interval maintaining means for changing and adjusting the position of the light receiving means along the perspective direction with respect to the measurement target location is provided,
Based on the product information and the control program about the size of the measurement object inputted in advance when the product of the measurement object changes, the control means of the measurement object to be located at the measurement target location A spectroscopic analyzer configured to control a change adjustment operation of the interval maintaining unit so that the interval between the largest object to be estimated and the light receiving unit is maintained at a set interval .

Light projection for changing and adjusting the position of the light projecting unit along the perspective direction with respect to the measurement target site so that the distance between the object to be measured and the light projecting unit located at the measurement target site can be changed and adjusted. Position adjusting means is provided,
Based on the product information about the size of the object to be measured and the control program input in advance when the product of the object to be measured changes, the control means determines the focal position of the focused light emitted from the light projecting means. The change adjustment operation of the light projection position adjusting means is controlled so as to coincide with the surface of the smallest object to be estimated among the objects to be measured that are to be located at the measurement target location. and has claim 1 spectrometer according.