JP2004213986A

JP2004213986A - Method and program for controlling lighting system, record medium with lighting device control program recorded, lighting system, and measurement machine

Info

Publication number: JP2004213986A
Application number: JP2002381021A
Authority: JP
Inventors: Hiroyuki Yoshida; 博行吉田
Original assignee: Mitutoyo Corp; Mitsutoyo Kiko Co Ltd
Current assignee: Mitutoyo Corp; Mitsutoyo Kiko Co Ltd
Priority date: 2002-12-27
Filing date: 2002-12-27
Publication date: 2004-07-29
Anticipated expiration: 2022-12-27
Also published as: JP4179871B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lighting system control method capable of executing synthesized illumination having predetermined illuminance and predetermined chromaticity by solving a problem wherein, since respective emission light sources have different relationships among an applied current value, illuminance and chromaticity on an individual basis, it is very difficult to generate synthesized illumination having the predetermined chromaticity with a directed illuminance. <P>SOLUTION: The illuminance and the chromaticity for the applied current value is measured for every light source to calculate a mixing ratio of emission intensities from the respective emission light sources required for synthesizing the synthesized illumination having the predetermined chromaticity with the illuminance directed by a directed value by using chromaticity variation according to illuminance variation of the emission light sources and a color composition theory equation (ST 33). The illuminance of each emission light source for generating the illuminance directed by the directed value is calculated from the mixing ratio (ST 34). The applied current value required for emitting light from each emission light source with the illuminance is read from a characteristic of the emission light source (ST 35). <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は、照明装置制御方法、照明装置制御プログラム、照明装置制御プログラムを記録した記録媒体、照明装置および測定機に関する。例えば、画像処理型測定機の照明について、照明の照度および色度を制御する照明装置制御方法、そのプログラム、そのプログラムを記録した記録媒体、照明装置およびこの照明装置を備える測定機に関する。
【０００２】
【背景技術】
被測定物に向かって光を照射する照明装置と、被測定物からの反射光を受光する受光センサと、受光センサで受光した画像から被測定物形状を画像処理によって求める画像処理装置とを備える画像処理型測定機が知られている。
この照明装置は、異なる発光色を発光する複数の発光光源と、各発光光源に対する印加電流を制御する印加電流制御部と、外部から操作可能に設けられ照明の照度を指示値として設定入力する指示値入力手段とを備えて構成されている。
【０００３】
近年では、発光光源としては発光ダイオードが知られ、赤色を発光する発光ダイオード（赤色ＬＥＤ）、緑色を発光する発光ダイオード（緑色ＬＥＤ）、青色を発光する発光ダイオード（青色ＬＥＤ）などが使用されるようになってきている。
各発光ダイオードの発光の色度（ｘ、ｙ）は予め規格されているので、所定の合成色例えばＣＩＥ１９３１色度座標（０．３、０．３）の白色光を合成するのに、各発光ダイオードの混合比（ｒ_Ｒ、ｒ_Ｇ、ｒ_Ｂ）が求められる。すると、指示値入力手段で指示された照度Ｌに応じた各発光ダイオードの発光照度は、それぞれ次のように求められる。赤色ＬＥＤの照度をＬ_Ｒ、緑色ＬＥＤの照度をＬ_Ｇ、青色ＬＥＤの照度をＬ_Ｂで表す。
【０００４】
Ｌ_Ｒ＝ｒ_ＲＬ
Ｌ_Ｇ＝ｒ_ＧＬ
Ｌ_Ｂ＝ｒ_ＢＬ
【０００５】
そこで、規格に従って、各発光ダイオードをＬ_Ｒ、Ｌ_Ｇ、Ｌ_Ｂの照度で発光させるための印加電流値が求められる。印加電流制御部は、各発光ダイオードに必要な印加電流を印加する。
【０００６】
このような構成において、ユーザーが指示値入力手段で照明の照度Ｌを指示する。すると、印加電流制御部は、指示された照度で所定の色度例えば白色の合成照明を照射するように各発光光源に対して所定の印加電流を印加する。この印加電流の印加により各発光光源が所定の照度（Ｌ_Ｒ、Ｌ_Ｇ、Ｌ_Ｂ）で発光することにより、指示された照度で白色の照明が被測定物に照射される。被測定物からの反射光が受光センサで受光され、受光された画像からのエッジ検出等により被測定物の形状または寸法等が測定される。
【０００７】
ここで、画像測定においては被測定物に照射する照明の照度および色度が非常に重要である。例えば、指示された照度に比べて実際の照明照度が暗い場合には、光量がたりずに画像を得ることができないかまたはエッジ検出ができない。指示された照度に比べて実際の照明照度が明るい場合には、光が飽和してしまうため画像がにじんで（画像がとんで）しまいエッジ検出を行うことができない。
また、照明の色度が白色光から色差を有する場合には、着色された被測定物の画像を正確にとれないため、エッジ検出を行うことができない。すなわち、赤色ＬＥＤ、緑色ＬＥＤ、青色ＬＥＤへの印加電流を制御して、合成照明の照度および色度を正確に制御することが精密な測定においては極めて重要である。
【０００８】
【発明が解決しようとする課題】
しかしながら、発光ダイオードは、各製品ごとに固体差を有していることから、規格通りに同じ値の印加電流を印加しても照度が固体ごとに異なるという問題がある。図１４（Ａ）（Ｂ）および図１５に、各照明装置ごとに赤色ＬＥＤ、緑色ＬＥＤおよび青色ＬＥＤをそれぞれ発光させた場合の印加電流値と照度との関係を示す。例えば、図１４（Ａ）の赤色ＬＥＤの照度特性において、印加電流が高くなると、すべての装置で照度も高くなるが、装置１と装置４との比較から分かる通り、印加電流値が高いところでは照度の差が非常に大きい。これは図１４（Ｂ）の緑色ＬＥＤおよび図１５の青色ＬＥＤにおいても同様である。すなわち、所定の照度で発光させるための印加電流値は各固体ごとに異なっているため、照度を指示したからといって印加電流値をただちに規定することができない。
規格に従って印加電流値を印加すると、各発光ダイオードの照度がずれて合成照明としても照度が指示値にならないという問題が生じる。また、各発光ダイオードの照度がずれていれば合成照明の色度もずれてしまうという問題が生じる。
【０００９】
さらに、発光ダイオードの発光色度は各製品ごとに個体差を有し、かつ、発光色度は発光強度に相関して変化していくという特性がある。図１６、図１７、図１８に各照明装置ごとに、赤色ＬＥＤ、緑色ＬＥＤおよび青色ＬＥＤをそれぞれ発光させた場合の照度と色度との関係を示す。
例えば、図１８（Ａ）に各照明装置について青色ＬＥＤの色度のｘ座標を示す。この図において、照度の変化に応じて色座標が変化していくのが分かる。また、各照明装置により色度が異なることが分かる。これは、図１６、図１７から赤色ＬＥＤ、緑色ＬＥＤについても同様である。
すなわち、各製品ごとに発光の色度が異なっているため、所定の合成照明を合成するための混合比を規格に従って決定すると、合成照明の色度は指示値とは異なってしまうという問題がある。
【００１０】
なお、固体ごとの照度特性の違いに留意しながら合成照明の照度を実現するのに、それぞれの発光ダイオードの発光強度を調整して印加電流値を変化させると、照度は確かに正確である。しかしながら、この場合、照度を変化させると色度も変化してしまうので、合成照明の色度がずれてしまうという問題が生じる。
逆に、色度に注目して、合成照明の色度を実現する発光ダイオードの色混合比を決定するにしても、固体ごとに発光色度が異なり、なおかつ、発光色度は照度によっても変化することを考えると、発光ダイオードの色度は一義に決まらないので、所定色度を合成するための混合比を単純に決定することはできない。
【００１１】
本発明の目的は、従来の問題を解消して、所定の照度および所定の色度を有する合成照明を照明することができる照明装置制御方法、照明装置制御プログラム、照明装置制御プログラムを記録した記録媒体、照明装置および測定機を提供することにある。
【００１２】
【課題を解決するための手段】
請求項１に記載の照明装置制御方法は、異なる発光色を発光する複数の発光光源と、前記各発光光源に対する印加電流を制御する印加電流制御手段と、照明の照度を指示する指示値を入力する入力手段とを備えた照明装置を制御して前記各発光光源からの各照明を合成して前記指示値で指示された照度および所定の色度を有する合成照明を生成する照明装置制御方法において、前記発光光源ごとに前記印加電流値に対する照度および色度を測定する光源特性測定工程と、前記光源特性測定工程で測定された前記発光光源の照度変化に応じた色度変化、および、複数の異なる色度の色から所定色度の合成色を合成するために必要な各色の強度の混合比を求める理論式を用いて、前記指示値で指示された照度で所定色度を有する合成照明を合成するために必要な前記各発光光源からの発光照度の混合比を算出する混合比算出工程と、前記混合比算出工程で算出された前記混合比から前記指示値で指示された照度を生成するための前記各発光光源の照度を算出する照度算出工程と、前記照度算出工程で算出された照度で前記各発光光源を発光させるために必要な前記印加電流値を前記光源特性測定工程で得られた前記発光光源の特性から読み取る印加電流値読出工程と、を備えていることを特徴とする。
【００１３】
このような構成によれば、異なる発光色を合成して、指示された照度で、かつ、所定の色度を有する合成色が生成される。
光源特性測定工程においては、発光光源ごとに印加電流値を変化させて、印加電流値に対する照度および色度の関係を調べる。発光光源は品質誤差により固体差を有するので、同じ印加電流値であっても固体ごとに照度も色度も異なり、また、照度が変化すると色度も変化するところ、予め各固体ごとに特性を調べておく。
【００１４】
混合比算出工程では、指示された照度で所定の色度を有する合成色を生成するための各発光光源の発光強度比である混合比を求める際に、各発光光源の固体ごとの特性を考慮する。そして、照度が変化すると色度も変化してしまうが、理論式を用いて所定の色度を合成できるかどうかを逐次確認しながら混合比を求める。
この求められた混合比から各発光光源の必要照度を求めて、さらに、この照度で発光させるための印加電流値を求める。そして、この印加電流値を各発光光源に印加すると、指示された照度で所定色度の合成照明を生成することができる。
【００１５】
請求項２に記載の照明装置制御方法は、請求項１に記載の照明装置制御方法において、前記混合比算出工程は、初期的に前記混合比として所定割合を有する第１仮混合比に設定する第１仮混合比設定工程と、前記第１仮混合比のもとで前記指示値にて指示された照度を生成するのに必要な前記各発光光源のそれぞれの照度を算出する仮照度算出工程と、前記仮照度算出工程で算出した前記各発光光源の照度におけるそれぞれの前記各発光光源の色度を前記光源特性測定工程での測定結果から読み出す色度読出工程と、前記色度読出工程で読み出された色度で合成照明の所定色度を生成するのに必要な前記各発光光源の発光強度の混合比を第２仮混合比として前記理論式に基づいて算出する第２仮混合比算出工程と、前記第１仮混合比と前記第２仮混合比とを比較する仮混合比比較工程と、前記仮混合比比較工程での比較結果に応じて前記第２仮混合比を改めて前記第１仮混合比として再設定する仮混合比再設定工程と、を備えていることを特徴とする。
【００１６】
このような構成において、初期的に第１仮混合比が設定され、この第１仮混合比のもとで指示された照度を合成するための各発光光源の照度が算出される。この照度で各発光光源を発光させた場合、合成色の照度は指示された照度になるものの、色度は所定の値になるとは限らない。そこで、色度読出工程で、各発光光源について照度に応じた色度を発光光源の特性から読み出す。そして、色合成理論により、この色度で所定色度を合成するための混合比を第２混合比として求める。もし、照度が変化しても色度が一定であるならば、この色合成理論で求められた混合比で所定の色度の合成色を合成できるはずであるが、照度の変化により色度も変化するため、第１仮混合比から第２仮混合比が大きくずれてしまう場合、第２仮混合比では所定の色度を合成できないと考えられる。
【００１７】
そこで、第１仮混合比と第２仮混合比とを比較して、両者の違いが許容範囲を超えている場合には、改めて第２仮混合比を第１仮混合比に再設定する。そして、第１仮混合比と第２仮混合比との違いが許容範囲内に収束するまで計算を繰り返す。
このように、発光光源の特性を考慮して、色合成理論による計算を計算結果が許容範囲に収束するまで繰り返すことにより、照度変化による色度の非線形な変化に関わらず、指示された照度で所定色度を有する合成色を生成する混合比を算出することができ、また、色合成理論による理論値と実際の色度との誤差を収束させることができる。
【００１８】
請求項３に記載の照明装置制御方法は、請求項２に記載の照明装置制御方法において、前記光源特性測定工程の後に、前記発光光源について色度の平均値を求める平均色度算出工程と、前記平均色度算出工程で算出された平均の色度に基づいて前記合成照明の所定色度を生成する前記発光光源の混合比を代表混合比として前記理論式により求める代表混合比算出工程と、を備え、前記第１仮混合比設定工程における前記第１仮混合比は、前記代表混合比であることを特徴とする。
【００１９】
このような構成によれば、発光光源の色度の平均値を各発光光源ごとに求めて、この色度の平均値を用いて色合成理論により所定色度を生成するための混合比を代表混合比として求める。そして、この代表混合比を第１仮混合比として第１仮混合比として初期設定する。
第１仮混合比と第２仮混合比との差が許容範囲に収束するまで色合成理論式による計算が行われるところ、当初から第１仮混合比と第２仮混合比とは近い値であった方が繰り返しの回数が減るので望ましいことはもちろんである。そこで、適当な割合を第１仮混合比とするよりも、色度の平均値に基づいて算出された代表混合比から出発すれば、最終結果に近いので収束が速く、計算を迅速に終えることができる。
【００２０】
請求項４に記載の照明装置制御方法は、請求項１ないし請求項３のいずれかに記載の照明装置制御方法において、前記印加電流値読出工程で読み出された前記印加電流値を実際に検証する検証工程と、前記検証工程での検証結果に基づいて前記印加電流値を修正する修正工程とを備え、前記検証工程は、前記印加電流値読出工程により読み出された前記印加電流値に従って前記各発光光源に印加電流を印加し、このときに点灯する合成照明の色度を測定する検証測定工程と、前記検証測定工程で測定された色度と目標とする所定色度とを比較する検証比較工程と、前記検証比較工程の比較結果から測定された色度と目標とする所定色度との色度差を色度補正量として記憶する色度補正量記憶工程とを備え、前記修正工程は、前記混合比算出工程における前記理論式にて前記混合比を求める際に目標とする所定色度を前記色度補正量の分だけずらして前記混合比を算出することを特徴とする。
【００２１】
このような構成によれば、理論的計算結果と実際とは誤差を有するところ、検証して修正することにより、実際に指示された照度で所定色度を有する合成色を正確に合成することができる。
理論的に求められた印加電流値で合成色を合成して、この合成色の色度を実際に測定する。このとき、目標とした所定色度と実際との誤差を色度補正量として求める。そして、色合成理論を適用する際には、この色度補正量を加味して計算の目標値を設定すれば、理論と実際との差を埋めて、実際の合成色の色度を目標の所定色度にすることができる。
【００２２】
請求項５に記載の照明装置制御方法は、請求項１ないし請求項４のいずれかに記載の照明装置制御方法において、前記印加電流値読出工程で読み出される前記印加電流値を前記指示値に対応させて記憶し、前記印加電流値と前記指示値とを対応づけたテーブルとして格納する指示値／電流値テーブル格納工程を備えていることを特徴とする。
【００２３】
このような構成によれば、指示値と印加電流値との関係を記録したテーブルを用意しておくので、指示値で照度が指示された際には、テーブルから印加電流値を読み出すだけですぐに合成色を照明することができる。また、種種の色度の場合についても、指示値と印加電流値との関係をテーブルとして記憶しておけば、種種の色度の合成色を指示された照度で照明することができる。
【００２４】
請求項６に記載の照明装置制御方法は、請求項１ないし請求項５のいずれかに記載の照明装置制御方法において、前記発光光源は、発光ダイオードを備えて構成されることを特徴とする。
【００２５】
このような構成によれば、発光ダイオードは、発光に必要な電流値が少なくてよいので、照明装置の消費電流を低減することができる。
また、発光光源としては、赤色ＬＥＤ（ｌｉｇｈｔｅｍｉｔｔｉｎｇｄｉｏｄｅ）、緑色ＬＥＤ、青色ＬＥＤの少なくとも三つの基本色を備えていることが好ましい。赤、緑、青を混色することによりすべての色を合成することができるからである。あるいは、さらに、黄色、紫、青緑など他の発光色の発光ダイオードを備えていてもよい。
【００２６】
請求項７に記載の照明装置制御プログラムは、異なる発光色を発光する複数の発光光源と、前記各発光光源に対する印加電流を制御し前記各発光光源からの各照明を合成して所定の照度および色度を有する合成照明を生成する印加電流制御手段と、照明の照度を指示する指示値を入力する入力手段とを備えた照明装置にコンピュータを組み込んで、このコンピュータに、前記発光光源ごとに前記印加電流値に対する照度および色度を測定する光源特性測定工程と、前記光源特性測定工程で測定された前記発光光源の照度変化に応じた色度変化と、複数の異なる色度の色から所定色度の合成色を合成するために必要な各色の強度の混合比を求める理論式と、を用いて前記指示値で指示された照度で所定色度を有する合成照明を合成するために必要な前記各発光光源からの発光強度の混合比を算出する混合比算出工程と、前記混合比算出工程で算出された前記混合比から前記指示値で指示された照度を生成するための前記各発光光源の照度を算出する照度算出工程と、前記照度算出工程で算出された照度で前記各発光光源を発光させるために必要な前記印加電流値を前記光源特性測定工程で得られた前記発光光源の特性から読み取る印加電流値読出工程と、を実行させることを特徴とする。
【００２７】
請求項８に記載の記録媒体は、異なる発光色を発光する複数の発光光源と、前記各発光光源に対する印加電流を制御し前記各発光光源からの各照明を合成して所定の照度および色度を有する合成照明を生成する印加電流制御手段と、照明の照度を指示する指示値を入力する入力手段とを備えた照明装置にコンピュータを組み込んで、このコンピュータに、前記発光光源ごとに前記印加電流値に対する照度および色度を測定する光源特性測定工程と、前記光源特性測定工程で測定された前記発光光源の照度変化に応じた色度変化と、複数の異なる色度の色から所定色度の合成色を合成するために必要な各色の強度の混合比を求める理論式と、を用いて前記指示値で指示された照度で所定色度を有する合成照明を合成するために必要な前記各発光光源からの発光強度の混合比を算出する混合比算出工程と、前記混合比算出工程で算出された前記混合比から前記指示値で指示された照度を生成するための前記各発光光源の照度を算出する照度算出工程と、前記照度算出工程で算出された照度で前記各発光光源を発光させるために必要な前記印加電流値を前記光源特性測定工程で得られた前記発光光源の特性から読み取る印加電流値読出工程と、を実行させる照明装置制御プログラムを記録したことを特徴とする。
【００２８】
このような構成によれば、請求項１に記載の発明と同様の作用効果を奏することができる。さらに、ＣＰＵ（中央処理装置）やメモリ（記憶装置）を有するコンピュータを組み込んでこのコンピュータに各工程を実行させるようにプログラムを構成すれば、各工程におけるパラメータを容易に変更することができる。そして、このプログラムを記録した記録媒体をコンピュータに直接差し込んでプログラムをコンピュータにインストールしてもよく、記録媒体の情報を読み取る読取装置をコンピュータに外付けし、この読取装置からコンピュータにプログラムをインストールしてもよい。なお、プログラムは、インターネット、ＬＡＮケーブル、電話回線等の通信回線や無線によってコンピュータに供給されてインストールされてもよい。
【００２９】
請求項９に記載の照明装置は、異なる発光色を発光する発光光源と、前記各発光光源に対する印加電流を制御する印加電流制御手段と、照明の照度を指示する指示値を入力する入力手段とを備え、前記各発光光源からの各照明を合成して所定の照度および色度を有する合成照明を生成する照明装置において、前記印加電流制御手段は、前記発光光源ごとに前記印加電流値に対する照度および色度を測定し記憶する光源特性測定手段と、前記光源特性測定手段で測定された前記発光光源の照度変化に応じた色度変化と、複数の異なる色度の色から所定色度の合成色を合成するために必要な各色の強度の混合比を求める理論式と、を用いて前記指示値で指示された照度で所定色度を有する合成照明を合成するために必要な前記各発光光源からの発光強度の混合比を算出する混合比算出手段と、前記混合比算出手段で算出された前記混合比から前記指示値で指示された照度を生成するための前記各発光光源の照度を算出する照度算出手段と、前記照度算出手段で算出された照度で前記各発光光源を発光させるために必要な前記印加電流値を前記発光光源の特性から読み取る印加電流読出手段と、前記印加電流読出手段で読み取られた前記印加電流値を前記指示値に対応させた指示値／電流値テーブルを格納する指示値／電流値テーブル格納手段とを備えていることを特徴とする。
【００３０】
このような構成によれば、請求項１に記載の発明と同様の作用効果を奏することができる。
【００３１】
請求項１０に記載の測定機は、被測定物に向かって光を照射する請求項９に記載の照明装置と、前記被測定物からの反射光を受光する受光センサと、前記受光センサで受光した画像から前記被測定物の形状を画像処理によって求める画像処理手段とを備えることを特徴とする。
【００３２】
このような構成によれば、照明装置から指示された照度で所定の色度の照明が被測定物に照射されるので、受光センサにて被測定物の正確な画像が取得される。よって、画像処理により正確な被測定物の形状を求めることができる。
【００３３】
【発明の実施の形態】
以下、本発明の実施の形態を図示例と共に説明する。
図１に、本発明の照明装置を備えた測定機として画像処理型測定機１を示す。この測定機１は、ステージ２上に載置された被測定物（不図示）に光を照射する照明装置３と、被測定物からの反射光を受光する撮像手段４と、撮像手段４で取得された画像から画像処理により被測定物形状を測定する画像処理手段５とを備えて構成されている。なお、図１中では、被測定物に代えてステージ２上に照明の照度および色度を測定する照度計６が載置されている。
【００３４】
照明装置３は、被測定物に対して真上から照明光を照射する落射照明装置３１と、被測定物と撮像手段４とを結ぶ光学軸Ａを中心軸とするリング状光束を被測定物に向かって照射するリング照明装置３２と、照明制御装置３３と、を備えて構成されている。
【００３５】
落射照明装置３１は、筐体３１１と、筐体３１１内に収納された発光光源としての赤色ＬＥＤ３９１、緑色ＬＥＤ３９２および青色ＬＥＤ３９３と、各光源からの光を集光しかつ合成するレンズ３１２と、各光源からの光をそれぞれレンズ３１２に導くダイクロイックミラー３１３とを備えて構成されている。ここで、ダイクロイックミラー３１３は、光の波長に応じて透過または反射する特性を有するものであり、各光源から発射された光を選択的に透過または反射させることにより、各光源からの光を効率よくレンズ３１２に導き合成するものである。落射照明装置３１から発射された合成照明は、ミラー３１４によって光軸Ａ側に向かって反射された後、光軸Ａ上に設けられたハーフミラー３１５によって被測定物に向かって反射される。
赤色ＬＥＤ３９１、緑色ＬＥＤ３９２、青色ＬＥＤ３９３はそれぞれ複数ずつ設けられ、以後の説明では、それぞれの色のグループを「群」として称する。
【００３６】
リング照明装置３２は、光軸Ａを中心軸とするリング状の筐体３２１と、筐体３２１内に設けられた発光光源としての赤色ＬＥＤ３９１、緑色ＬＥＤ３９２、青色ＬＥＤ３９３と、各光源からの光を被測定物に向かって反射する反射ミラー３２３と、各光源からの光を反射ミラー３２３に導くダイクロイックミラー３２４とを備えて構成されている。赤色ＬＥＤ３９１、緑色ＬＥＤ３９２、青色ＬＥＤ３９３の光源は光軸Ａを囲んでリング状に複数配列されている。ダイクロイックミラー３２４は、各光源からの光を光軸Ａ側とは反対方向に反射する。反射ミラー３２３は、ダイクロイックミラー３２４からの光を被測定物に向かって反射する。
【００３７】
照明制御装置３３は、図２に示されるように、照明の照度を指示する指示値を設定入力する入力手段３４と、指示値とそれぞれの光源群３９１〜３９３に対する印加電流値との関係を有する指示値／電流値テーブル３６を格納するメモリ（指示値／電流値テーブル格納手段）３５と、各光源へ印加電流を印加するドライバ３７と、中央制御装置（ＣＰＵ）３８とを備えて構成されている。ここで、メモリ３５、ドライバ３７、およびＣＰＵ３８により印加電流制御手段が構成されている。
【００３８】
入力手段３４は、外部に臨んで設けられ手動操作可能に設けられたレバーあるいはボタン等で構成されている。入力手段３４で設定入力された指示値はＣＰＵ３８に送られる。
【００３９】
指示値／電流値テーブル３６は、図３に示されるように、指示値に対して赤色ＬＥＤ群３９１、緑色ＬＥＤ群３９２、青色ＬＥＤ群３９３の各発光ダイオード群に印加する印加電流値が記録されたテーブルである。なお、この指示値／電流値テーブル３６は、各発光ダイオード群３９１〜３９３の照度特性、色度特性および製品間の固体差を校正して、指示された指示値の照度で所定の合成色である白色光を照明するために各発光ダイオード群、赤色ＬＥＤ群３９１、緑色ＬＥＤ群３９２、青色ＬＥＤ群３９３のそれぞれに印加する印加電流値を求めて作成されたものである。合成色の色度としては任意であるが、以後ＣＩＥ１９３１色度座標（０．３、０．３）の白色の合成色として説明する。
この指示値／電流値テーブル３６の作成については後述する。
【００４０】
ＣＰＵ３８は、入力手段３４からの指示値に従って、メモリ３５に格納された指示値／電流値テーブル３６から指示された指示値に対応する印加電流値を赤色ＬＥＤ群３９１、緑色ＬＥＤ群３９２、青色ＬＥＤ群３９３について読み出す。ＣＰＵ３８は、読み出した印加電流値をドライバ３７に指令する。
また、ＣＰＵ３８は、光源特性測定手段、混合比算出手段、照度算出手段、印加電流読出手段等を備えているが、これら各手段の動作についてはフローチャートを用いて説明する。
【００４１】
ドライバ３７は、各発光ダイオード群３９１〜３９３に電流を印加して発光ダイオードを発光させるものであり、赤色ＬＥＤ群３９１に電流を印加する赤色ＬＥＤドライバ３７１と、緑色ＬＥＤ群３９２に電流を印加する緑色ＬＥＤドライバ３７２と、青色ＬＥＤ群３９３に電流を印加する青色ＬＥＤドライバ３７３とを備えて構成されている。ドライバ３７は、ＣＰＵ３８から印加電流値の指令を受けて、各ドライバ３７１〜３７３から各発光ダイオード群へ電流を印加する。
【００４２】
撮像手段４は、被測定物からの反射光を集光する撮像レンズ４１と、撮像レンズ４１からの光を撮像する撮像素子を有するＣＣＤカメラ（ｃｈａｒｇｅｃｏｕｐｌｅｄｄｅｖｉｃｅ）４２とを備えて構成されている。
【００４３】
次に、指示値／電流値テーブル３６を作成する指示値／電流値テーブル作成工程について説明する。
指示値／電流値テーブル３６の作成にあたり、ステージ２上に照明の照度および色度を測定する照度色度センサとしてのカラー照度計６を設置する。カラー照度計６で測定された照明の照度および色度のデータはＣＰＵ３８に送信される。
【００４４】
指示値／電流値テーブル３６を作成する指示値／電流値テーブル作成工程は、図４のフローチャートに示すように、指示値に対する照明照度を設定する指示値／照度テーブル作成工程ＳＴ１と、各発光ダイオード群の照度および色度の特性を基礎データとして取得する基礎データ準備工程ＳＴ２と、基礎データ準備工程ＳＴ２で取得された各発光ダイオード群３９１〜３９３の特性に基づいて指示値とこの指示値で指示された照度で所定合成色を生成するのに必要な印加電流値との関係を表す指示値／電流値の仮テーブルを作成する指示値／電流値仮テーブル作成工程ＳＴ３と、指示値／電流値仮テーブルを検証する検証工程ＳＴ４と、検証工程ＳＴ４での検証結果に基づいて指示値／電流値仮テーブルを修正する修正工程ＳＴ７とを備えて構成されている。
なお、これらの各工程はプログラミングされて、ＣＰＵ３８にてこのプログラミングが実行されることによって上記各工程は処理される。
【００４５】
指示値／照度テーブル作成工程ＳＴ１について説明する。
指示値［％］と照度［Ｌｘ］との関係は、横軸に指示値をとり縦軸に照度をとると、例えば図５（Ａ）のように、指示値に対応して照度が決定される制御カーブで表される。この関係は予めＣＰＵ３８内に記憶させておいてもよく、あるいは、入力手段３４により新たに設定してもよい。そして、ＣＰＵ３８により、この制御カーブから指示値に対応した照度が読み出され、例えば図５（Ｂ）のように、指示値に対して照度が表された指示値／照度テーブルが作成される。
【００４６】
基礎データ準備工程ＳＴ２について説明する。
基礎データ準備工程ＳＴ２は、図６のフローチャートに示されるように、印加電流値と赤色ＬＥＤ群３９１の特性との関係を測定する工程ＳＴ２１と、印加電流値と緑色ＬＥＤ群３９２の特性との関係を測定する工程ＳＴ２２と、印加電流値と青色ＬＥＤ群３９３の特性との関係を測定する工程ＳＴ２３と、各発光ダイオード３９１〜３９３について色度の平均値を求める工程（平均色度算出工程）ＳＴ２４と、平均の色度に基づいて所定合成色つまりＣＩＥ１９３１色度座標（０．３、０．３）の合成色を生成するための代表混合比を求める工程（代表混合比算出工程）ＳＴ２５とを備えている。
【００４７】
印加電流値と赤色ＬＥＤ群３９１の特性との関係の測定ＳＴ２１について説明する。
ＣＰＵ３８は、赤色ＬＥＤ群３９１の特性を調べるに際して、赤色ＬＥＤドライバ３７１に０から順番に印加電流を上げていく指令を送る。すると、赤色ＬＥＤドライバ３７１が０から順番に印加電流が赤色ＬＥＤ群３９１に印加され、赤色ＬＥＤ群３９１が印加電流値に応じて発光する。この時、カラー照度計６は、赤色ＬＥＤ群３９１からの照明照度および色度を測定する。測定結果は、ＣＰＵ３８に送られる。ＣＰＵ３８では、赤色ＬＥＤ群３９１への印加電流値とこの印加電流での照度および色度との関係を記憶する。この関係は、例えば、図７に示されるように、印加電流値に対する赤色ＬＥＤ群３９１の色度（ｘ、ｙ）および照度の関係としてテーブルに記録される。
【００４８】
赤色ＬＥＤ群３９１について電流値０から有効範囲の電流値（例えば、１６ビットで制御した場合、６５５３６）までについて測定が終了すると、次は、緑色ＬＥＤ群３９２、そして青色ＬＥＤ群３９３について印加電流値と特性との関係が測定され（ＳＴ２２、ＳＴ２３）、測定結果として図７の印加電流値と照度および色度との関係のテーブルが作成される。
なお、ＳＴ２１、ＳＴ２２、ＳＴ２３により光源特性測定工程が構成される。
【００４９】
次に、各発光ダイオード群３９１〜３９２について、群ごとに色度の平均値が求められる（ＳＴ２４）。すなわち、ＣＰＵ３８により、各発光ダイオード群３９１〜３９３について、各印加電流値で測定された色度を平均化した値が求められる。各発光ダイオード群３９１〜３９３の色度の平均値は図７の最下欄に示される。
【００５０】
次に、代表混合比が求められる（ＳＴ２５）。代表混合比とは、各発光ダイオード３９１〜３９３の発光色度を平均色度であるとした場合に、ＣＩＥ１９３１色度座標（０．３、０．３）の合成色を合成するための発光ダイオード群、赤色ＬＥＤ群３９１、緑色ＬＥＤ群３９２、青色ＬＥＤ群３９３の発光強度比である。
【００５１】
任意の合成色（ｘ、ｙ、Ｅ）を合成するための混合比は、色合成理論の式から求められる。色合成理論について説明する。
発光の強度をＥで表す。また、赤色ＬＥＤ群３９１のＣＩＥ値を（ｘ_Ｒ、ｙ_Ｒ、Ｅ_Ｒ）、緑色ＬＥＤ群３９２のＣＩＥ値を（ｘ_Ｇ、ｙ_Ｇ、Ｅ_Ｇ）、青色ＬＥＤ群３９３のＣＩＥ値を（ｘ_Ｂ、ｙ_Ｂ、Ｅ_Ｂ）とする。
このとき、合成色（ｘ、ｙ、Ｅ）は、次の式で表される。
【００５２】
【数１】

【００５３】
（式１）から、Ｔ_Ｒ、Ｔ_Ｇ、Ｔ_Ｂについて解くと次のようになる。
【００５４】
【数２】

【００５５】
従って、合成色（ｘ、ｙ、Ｅ）を合成するための各発光ダイオード群３９１〜３９３の強度は次のように表される。
【００５６】
【数３】

【００５７】
この各発光ダイオード群３９１〜３９３の強度Ｅ_Ｒ、Ｅ_Ｇ、Ｅ_Ｂの比から、合成照明の色度（ｘ、ｙ）を合成する混合比（ｒ_Ｒ、ｒ_Ｇ、ｒ_Ｂ）が求められる。
【００５８】
そこで、各発光ダイオード群３９１〜３９３の平均色度を、赤色ＬＥＤ群３９１について（ｘ_Ｒａｖｅ、ｙ_Ｒａｖｅ）、緑色ＬＥＤ群３９２について（ｘ_Ｇａｖｅ、ｙ_Ｇａｖｅ）、青色ＬＥＤ群３９３について（ｘ_Ｂａｖｅ、ｙ_Ｂａｖｅ）として、（式３）より、ＣＩＥ１９３１色度座標（０．３、０．３、１）の合成色を合成するための代表混合比（ｒ_Ｒａｖｅ、ｒ_Ｇａｖｅ、ｒ_Ｂａｖｅ）がＣＰＵ３８により求められる。
【００５９】
次に、指示値／電流値仮テーブル作成工程ＳＴ３について説明する。
指示値／電流値仮テーブル作成工程（図４、ＳＴ３）は、図８に示されるように、合成色（０．３、０．３、Ｌｉ）を生成する混合比を算出する混合比算出工程ＳＴ３３と、混合比算出工程ＳＴ３３で算出された混合比から各発光ダイオード群３９１〜３９３それぞれの発光光源の照度を算出する照度算出工程ＳＴ３４と、各発光ダイオード群３９１〜３９３を照度算出工程で算出された照度で発光させる印加電流値を読み出す電流値読出工程（印加電流値読出工程）ＳＴ３５とを備えている。
【００６０】
指示値／電流値仮テーブル作成工程ＳＴ３においては、まず、指示値／照度テーブル（図５（Ｂ））から指示値ｉに対する照度Ｌｉが読み出される（ＳＴ３２）。このとき、指示値ｉのカウンタｉは、はじめゼロに初期設定される（ＳＴ３１）。ＳＴ３２からＳＴ３５までを完了したところで、順次カウンタｉを１ずつカウントアップして（ＳＴ３８）、すべての指示値ｉについてＳＴ３２からＳＴ３５が行われる（ＳＴ３６）。
【００６１】
混合比算出工程（ＳＴ３３）について説明する。
混合比算出工程ＳＴ３３は、図９に示されるように、各発光ダイオード群３９１〜３９３の発光強度の暫定的な混合比を第１仮混合比として設定する第１仮混合比設定工程ＳＴ３３１と、第１仮混合比のもとで合成照明の所定照度を生成するのに必要な各発光ダイオード群３９１〜３９３それぞれの照度を求める仮照度算出工程ＳＴ３３２と、仮照度算出工程ＳＴ３３２で算出した各発光ダイオード群３９１〜３９３の照度におけるそれぞれの発光ダイオード群３９１〜３９３の色度を読み出す色度読出工程ＳＴ３３３と、色度読出工程ＳＴ３３３で読み出された色度で合成照明の所定色度を生成するために必要な各発光ダイオード群３９１〜３９３の発光強度の混合比を第２仮混合比として算出する第２仮混合比算出工程ＳＴ３３４と、第１仮混合比と第２仮混合比とを比較する仮混合比比較工程ＳＴ３３５と、仮混合比比較工程ＳＴ３３５での比較結果に応じて第２仮混合比を改めて第１仮混合比として再設定する仮混合比再設定工程ＳＴ３３８とを備えている。
【００６２】
第１仮混合比設定工程ＳＴ３３１は、まず、各発光ダイオード群３９１〜３９３の発光強度比である第１仮混合比（ｒ_Ｒｉ、ｒ_Ｇｉ、ｒ_Ｂｉ）を先に求められた代表混合比（ｒ_Ｒａｖｅ、ｒ_Ｇａｖｅ、ｒ_Ｂａｖｅ）に暫定的に設定する。
【００６３】
仮照度算出工程ＳＴ３３２は、第１仮混合比で合成照明の照度Ｌｉを生成するのに必要な各発光ダイオード群３９１〜３９３の照度（Ｌ_Ｒｉ、Ｌ_Ｇｉ、Ｌ_Ｂｉ）を算出する。ここで、各発光ダイオード群３９１〜３９３の照度は、次の式で求められる。
【００６４】
Ｌ_Ｒｉ＝ｒ_ＲｉＬ_ｉ
Ｌ_Ｇｉ＝ｒ_ＧｉＬ_ｉ（式４）
Ｌ_Ｂｉ＝ｒ_ＧｉＬ_ｉ
【００６５】
ちなみに、今、第１仮混合比を代表混合比に設定（ＳＴ３３１）している。代表混合比は、発光強度に関わり無く、各発光ダイオード群３９１〜３９３の色度が常に平均の色度で一定であると仮定した場合にＣＩＥ１９３１色度座標（０．３、０．３）の合成色を合成するための混合比として設定されたものである。従って、（Ｌ_Ｒｉ、Ｌ_Ｇｉ、Ｌ_Ｂｉ）で各発光ダイオード群３９１〜３９３を発光させた場合、照度に関しては照度Ｌ_ｉになるが、色度に関して実際のところは、発光強度の違いにより色度が変化するため、合成照明の色度がＣＩＥ１９３１色度座標（０．３、０．３）にはならない可能性がある点に留意する。
【００６６】
色度読出工程ＳＴ３３３では、仮照度算出工程ＳＴ３３２で算出された照度（Ｌ_Ｒｉ、Ｌ_Ｇｉ、Ｌ_Ｂｉ）で発光ダイオード群３９１〜３９３が発光した時の色度を読み出す。これは、先に基礎データ準備工程ＳＴ２で用意した印加電流値と照度および色度とのテーブル（図７）から、照度に対する色度を読み出す。
赤色ＬＥＤ群３９１、緑色ＬＥＤ群３９２、青色ＬＥＤ群３９３のそれぞれについて、
赤色ＬＥＤ群３９１が照度Ｌ_Ｒｉのときの色度、Ｒ＝（ｘ_Ｒｉ、ｙ_Ｒｉ）
緑色ＬＥＤ群３９２が照度Ｌ_Ｇｉのときの色度、Ｇ＝（ｘ_Ｇｉ、ｙ_Ｇｉ）
青色ＬＥＤ群３９３が照度Ｌ_Ｂｉのときの色度、Ｂ＝（ｘ_Ｂｉ、ｙ_Ｂｉ）
であると読み出されたとする。
読み出された色度が、平均の色度からずれていた場合には、この色度で合成色の色度（０．３、０．３）を合成する混合比は、第１仮混合比（現段階では代表混合比）からずれてくることに留意する。
【００６７】
第２仮混合比算出工程ＳＴ３３４は、色度読出工程ＳＴ３３３で読み出された色度で、合成照明の色度、ＣＩＥ１９３１色度座標（０．３、０．３）を生成するときの混合比を第２仮混合比（ｒ_Ｒｉ’、ｒ_Ｇｉ’、ｒ_Ｂｉ’）として色合成理論に基づいて算出する。
（式３）により、合成照明の色度（０．３、０．３）を生成するために必要な各発光ダイオード群３９１〜３９３の発光強度、すなわち、Ｅ_Ｒ、Ｅ_Ｇ、Ｅ_Ｂが求められる。従って、第２仮混合比（ｒ_Ｒｉ’、ｒ_Ｇｉ’、ｒ_Ｂｉ’）は、（Ｅ_Ｒ、Ｅ_Ｇ、Ｅ_Ｂ）の比として求められる。
【００６８】
仮混合比比較工程ＳＴ３３５は、第１仮混合比と第２仮混合比とを比較する。第１仮混合比の各成分と、第２仮混合比の各成分とを成分ごとに対比して比較する。
ここで、色合成理論では、第１仮混合比による照度で発光する場合の色度に基づいて計算を行って第２仮混合比を算出するものであるところ、照度の変化によって色度が非線形に変化するので、第２仮混合比で合成照明を合成した場合でもＣＩＥ１９３１色度座標（０．３、０．３）の合成照明を生成することができないこともありうる。そこで、ＳＴ３３８において、第２仮混合比を第１仮混合比として再設定する繰り返しの収束処理を行い、仮混合比比較工程ＳＴ３３５において収束の程度を判定する。
【００６９】
仮混合比比較工程ＳＴ３３５は、第１仮混合比（ｒ_Ｒｉ、ｒ_Ｇｉ、ｒ_Ｂｉ）と第２仮混合比（ｒ_Ｒｉ’、ｒ_Ｇｉ’、ｒ_Ｂｉ’）との各成分ごとの違いを所定量εと比較する。そして成分ごとの違いが所定量ε未満である場合（ＳＴ３３６：ＹＥＳ）、すなわち、次の関係式５を満たす場合には、第２仮混合比を指示値ｉに対する仮混合比として設定する。ここで、所定量εは、照度の変化にともなう色度変化が許容できる範囲に収まる程度の第１仮混合比と第２仮混合比との差である。
【００７０】
｜ｒ_Ｒｉ−ｒ_Ｒｉ’｜＜ε
｜ｒ_Ｇｉ−ｒ_Ｇｉ’｜＜ε
｜ｒ_Ｂｉ−ｒ_Ｂｉ’｜＜ε （式５）
【００７１】
また、（式５）の関係を満たさない場合（ＳＴ３３６：ＮＯ）には、第２仮混合比を第１仮混合比として再設定して（ＳＴ３３８）、第１仮混合比と第２仮混合比とが収束して式５を満たすまで、ＳＴ３３２からＳＴ３３５が繰り返される。
【００７２】
次に、照度算出工程（図８、ＳＴ３４）は、仮混合比のもとで、合成照明の照度Ｌ_ｉを生成するための各発光ダイオード群３９１〜３９３の照度（Ｌ_Ｒｉ，Ｌ_Ｇｉ，Ｌ_Ｂｉ）を求める。これは、（式４）にならって求められる。
電流値読出工程ＳＴ３５は、各発光ダイオード群３９１〜３９３を照度算出工程ＳＴ３４で算出された照度で発光させる印加電流値を図７から読み出し、指示値ｉに対する各発光ダイオード群３９１〜３９３の印加電流値として記憶する。すべての指示値ｉに対して、すなわち、有効範囲にあるすべてのカウンタｉに対してＳＴ３２からＳＴ３５を行ったのち（ＳＴ３６：ＹＥＳ）、指示値ｉに対する各発光ダイオードの電流値をテーブルにして指示値／電流値仮テーブルとする（ＳＴ３７）。
【００７３】
次に、指示値／電流値仮テーブルを実際に検証する検証工程を行う（図４、ＳＴ４）。すなわち、指示値／電流値仮テーブルに従って合成照明を点灯させ、点灯した照明の色度がＣＩＥ１９３１色度座標（０．３、０．３）になっているかどうかを検証する。
検証工程ＳＴ４は、図１０に示されるように、合成照明を点灯させて色度を測定する検証測定工程ＳＴ４１と、測定された色度と目標とする所定色度とを比較する検証比較工程ＳＴ４２と、検証比較工程ＳＴ４２の比較結果から測定された色度と目標とする所定色度との差を色度補正量として記憶する色度補正量記憶工程ＳＴ４３とを備えている。
【００７４】
検証測定工程ＳＴ４１では、指示値／電流値仮テーブルに従って合成照明を点灯させる。この際の合成照明の照度は任意であり、適当な指示値ｉを指示して合成照明を点灯させる。そして、点灯した合成照明の色度（ｘ_ｉ，ｙ_ｉ）を測定する。
ここで、指示値／電流値仮テーブルは、色合成理論に基づく計算から合成照明の色度をＣＩＥ１９３１色度座標（０．３、０．３）にするべく求められたものである。しかしながら、目標とする合成照明の色度をＣＩＥ１９３１色度座標（０．３、０．３）に据えて色合成理論を適用した場合でも、理論値と現実に合成される色度との間にはずれが生じることがある（図１１参照）。
【００７５】
検証比較工程ＳＴ４２では、測定された色度と目標とする色度（０．３、０．３）とを各成分ごとに所定の許容量αと比較する。そして成分ごとの違いが所定量α未満である場合（ＳＴ４２：ＹＥＳ）、すなわち、次の関係式６を満たす場合には、指示値／電流値仮テーブルに従って点灯される合成照明は許容値内であり、検証ＯＫであると判断する（ＳＴ４５）。ここで、所定量αは、被測定物を画像処理測定する場合に、測定に影響を与えない程度の色差である。
【００７６】
｜ｘ_ｉ−０．３｜＜α
｜ｙ_ｉ−０．３｜＜α （式６）
【００７７】
検証結果がＯＫである場合（ＳＴ４５）には、指示値／電流値仮テーブルを正式な指示値／電流値テーブルとして格納する（指示値／電流値テーブル格納工程、図４、ＳＴ６）
【００７８】
一方、関係式６を満たさない場合、成分ごとの違いを色度補正量として記憶する（ＳＴ４３）。すなわち、色度補正量（ｃ_ｘ、ｃ_ｙ）は次の式で表される。
ｃ_ｘ＝０．３−ｘ_ｉ
ｃ_ｙ＝０．３−ｙ_ｉ（式７）
色度補正量は、色合成理論で目標とした色度と実際に点灯された合成色の色度とのずれであることから、色合成理論で目標とする色度を色度補正量の分だけずらしておけば、実際に点灯される合成色の色度は目標値に合致すると考えられる。
【００７９】
色度補正量を記憶したのち、指示値／電流値仮テーブルの修正が行われる（図４、ＳＴ７）。
指示値／電流値仮テーブルの修正を図１２のフローチャートに示す。修正工程ＳＴ７は、図１２に示されるように、基本的には指示値／電流値仮テーブル作成工程ＳＴ３と同じであり、図１２は、図８と図９とを合わせたものに対応している。
修正工程ＳＴ７では、ＳＴ７７において、色合成理論により第２仮混合比を算出する際に、直前（ＳＴ７６）で読み出した色度補正量（ｃ_ｘ、ｃ_ｙ）を加味した色度（０．３＋ｃ_ｘ、０．３＋ｃ_ｙ）を目標の色度として計算を行う。
このように、色合成理論と実際とのずれを色度補正量として予め加味しておくことにより、実際に点灯された合成色の色度を目標の色度とすることができる（図１３参照）。
【００８０】
修正された指示値／電流値仮テーブルは、再び検証され（図４、ＳＴ４）、検証結果が良ければ（ＳＴ５：ＹＥＳ）、正式な指示値／電流値テーブル３６として格納される（ＳＴ６）。
【００８１】
次に、画像処理型測定機１の使用および動作について説明する。
画像処理型測定機１で被測定物を測定するにあたって、まず、ステージ２上に被測定物を載置する。そして、入力手段３４で照明装置３の照度を指示する指示値を入力する（入力工程）。すると、ＣＰＵ３８は、指示値／電流値テーブル３６から入力された指示値に対する各発光ダイオード群３９１〜３９３への印加電流値を読出し、この印加電流値をドライバ３７に指示する。ドライバ３７から各発光ダイオード群３９１〜３９３に対して印加電流が印加されると、落射照明装置３１およびリング照明装置３２からの照明が発射されて、指示された照度で白色の合成照明が被測定物に照射される（発光工程）。被測定物からの反射光は撮像手段４で撮像され、画像処理手段５により撮像された画像から演算処理により被測定物の形状が測定される。画像処理手段５での演算結果は、ＣＲＴ等の表示装置で表示されるか、あるいはプリンタ等の出力装置から出力される。
【００８２】
以上、このような構成によれば、次の効果を奏することができる。
（１）基礎データ準備工程ＳＴ２において、各発光ダイオード群３９１〜３９３の特性を調べておき、この特性に基づいて指示値で指示される照度で白色の合成色を生成する印加電流値が求められる。よって、発光ダイオードに固体差があっても、指示通りの照度かつ白色の照明を被測定物に照射することができる。その結果、正確に被測定物の画像を撮像することができる。また、被測定物の着色に関わらず画像を得ることができる。
【００８３】
（２）混合比算出工程ＳＴ３３において、色度が照度に応じて変化することを考慮して、色合成理論により算出した所定色度を生成するための第２仮混合比を、第１仮混合比と比較して、この第１仮混合比と第２仮混合比とが収束するまで計算を繰り返し行う。よって、所定色度の照明を合成するための混合比を正確に求めることができる。
【００８４】
（３）各発光ダイオード群３９１〜３９３ごとの平均色度を算出しておき、この平均色度に基づいて所定色度の合成色を生成するための代表混合比を算出する。そして、この代表混合比から出発して混合比算出工程の計算を行う。その結果、混合比算出工程ＳＴ３３での計算の繰り返し回数を少なくして、迅速に混合比を算出することができる。
【００８５】
（４）検証工程ＳＴ４において、色合成理論に基づいて求められた指示値／電流値仮テーブルを検証する。このとき、実際に照明された合成照明の色度が所定色度からずれている場合、このずれている量を色度補正量とする。そして、色合成理論での目標値を色度補正量の分だけずらして混合比を算出して修正を行う。よって、理論と実際とのずれを修正し、正確に所定色度の合成照明を生成することができる。
【００８６】
（５）指示値に対する印加電流値は、指示値／電流値テーブル３６として用意されているので、入力手段３４で指示値が指示された際には、この指示値／電流値テーブル３６から読み出すだけであり、指示値の変更に対する応答を迅速にできる。
【００８７】
尚、本発明は、上記実施形態にのみ限定されるものではなく、本発明の要旨を逸脱しない範囲内において種々変更を加え得ることは勿論である。
印加電流値をすべての指示値に対して予め求めておいて指示値／電流値テーブル３６として格納しておく例について説明したが、テーブルとして備えていなくても、指示値が指示された場合に混合比の算出、照度の算出、印加電流値の読出し等の処理を逐次行ってもよい。
【００８８】
検証工程ＳＴ４は、指示値／電流値テーブル３６を作成した後に行う例について説明したが、１つの任意の指示値に対する印加電流値を求めたのちにすぐ検証を行って、色度補正量を算出して、この色度補正量を加味して指示値／電流値テーブル３６を作成してもよい。あるいは、各照明装置３１、３２ごとに色度補正量が予め分かっている場合には、はじめからこの色度補正量を加味して色合成理論を適用して計算し指示値／電流値テーブル３６を作成してもよい。
【００８９】
所定色度としてはＣＩＥ１９３１色度座標（０．３、０．３）とする場合について説明したが、目標とする所定色度は任意であることはもちろんである。合成照明の種種の色度について、色度ごとに指示値／電流値テーブル３６を用意しておけば、種種の色度の合成照明を指示された照度で生成することができる。
【００９０】
発光光源は特に発光ダイオードに限られるものではなく、また、発光ダイオードの色も赤、緑、青の他、黄や紫などを備えていてもよい。発光光源の色種が多くても本発明を適用することにより、指示された照度で所定の色度の合成色を合成できることはいうまでもない。
【００９１】
【発明の効果】
以上、説明したように本発明の照明装置制御方法、照明装置制御プログラム、照明装置制御プログラムを記録した記録媒体、測定機によれば、所定の照度および所定の色度を有する合成照明を照明することができるという優れた効果を奏し得る。
【図面の簡単な説明】
【図１】本発明の一実施形態として画像処理型測定機を示す図である。
【図２】前記実施形態において、照明制御装置の構成を示す図である。
【図３】前記実施形態において、指示値／電流値テーブルを示す図である。
【図４】図３の指示値／電流値テーブルを作成する指示値／電流値テーブル作成工程を示すフローチャートである。
【図５】（Ａ）は、指示値と照度の関係を設定する制御カーブを示す図である。（Ｂ）は、指示値と照度とのテーブルを示す図である。
【図６】基礎データ準備工程を示すフローチャートである。
【図７】印加電流値に対する各発光光源群の特性を示す図である。
【図８】指示値／電流値仮テーブル作成工程を示すフローチャートである。
【図９】混合比算出工程を示すフローチャートである。
【図１０】検証工程を示すフローチャートである。
【図１１】理論値と実際とのずれを示す図である。
【図１２】修正工程を示すフローチャートである。
【図１３】修正後の合成照明における照度と色度とを示す図である。
【図１４】（Ａ）は、各照明装置ごとに赤色ＬＥＤ群の印加電流値と照度との関係を示す図である。（Ｂ）は、各照明装置ごとに緑色ＬＥＤ群の印加電流値と照度との関係を示す図である。
【図１５】各照明装置ごとに青色ＬＥＤ群の印加電流値と照度との関係を示す図である。
【図１６】各照明装置ごとに赤色ＬＥＤ群の照度と色度との関係を示す図である。
【図１７】各照明装置ごとに緑色ＬＥＤ群の照度と色度との関係を示す図である。
【図１８】各照明装置ごとに青色ＬＥＤ群の照度と色度との関係を示す図である。
【符号の説明】
１画像処理型測定機
３照明装置
４撮像手段
５画像処理手段
６照度計
３１落射照明装置
３２リング照明装置
３３照明制御装置
３４入力手段
３５メモリ
３６指示値／電流値テーブル
３７ドライバ
３８中央制御装置
３９１赤色ＬＥＤ群
３９２緑色ＬＥＤ群
３９３青色ＬＥＤ群[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a lighting device control method, a lighting device control program, a recording medium storing the lighting device control program, a lighting device, and a measuring device. For example, the present invention relates to an illuminating device control method for controlling the illuminance and chromaticity of an illuminating device, a program, a recording medium storing the program, an illuminating device, and a measuring device including the illuminating device.
[0002]
[Background Art]
An illumination device that irradiates light to an object to be measured, a light receiving sensor that receives reflected light from the object to be measured, and an image processing device that obtains a shape of the object to be measured from an image received by the light receiving sensor by image processing. Image processing type measuring machines are known.
The lighting device includes a plurality of light sources that emit different emission colors, an applied current control unit that controls an applied current to each light source, and an instruction that is provided to be operable from the outside and sets and inputs the illuminance of illumination as an instruction value. And value input means.
[0003]
In recent years, light emitting diodes have been known as light emitting sources, and light emitting diodes that emit red light (red LEDs), light emitting diodes that emit green light (green LEDs), light emitting diodes that emit blue light (blue LEDs), and the like are used. It is becoming.
Since the chromaticity (x, y) of light emission of each light emitting diode is standardized in advance, each light emission is used to synthesize white light of a predetermined combined color, for example, CIE1931 chromaticity coordinates (0.3, 0.3). Diode mixing ratio (r_R, R_G, R_B) Is required. Then, the light emission illuminance of each light emitting diode according to the illuminance L designated by the designated value input means is obtained as follows. Set the illuminance of the red LED to L_R, The illuminance of the green LED is L_G, The illuminance of the blue LED is L_BExpressed by
[0004]
L_R= R_RL
L_G= R_GL
L_B= R_BL
[0005]
Therefore, according to the standard, each light emitting diode is set to L_R, L_G, L_BAn applied current value for emitting light with the illuminance of is obtained. The applied current control unit applies an applied current necessary for each light emitting diode.
[0006]
In such a configuration, the user designates the illuminance L of the illumination with the designated value input means. Then, the applied current control unit applies a predetermined applied current to each light emitting light source so as to irradiate a predetermined chromaticity, for example, white composite illumination with the designated illuminance. By applying the applied current, each light source emits a predetermined illuminance (L_R, L_G, L_B), White light is illuminated on the measured object with the designated illuminance. The light reflected from the object is received by the light receiving sensor, and the shape or size of the object is measured by detecting edges from the received image.
[0007]
Here, in image measurement, the illuminance and chromaticity of the illumination applied to the object to be measured are very important. For example, when the actual illumination illuminance is darker than the instructed illuminance, an image cannot be obtained or the edge cannot be detected because there is not enough light. If the actual illumination illuminance is brighter than the instructed illuminance, the light will be saturated, and the image will bleed (image will bleed out), making it impossible to perform edge detection.
In addition, when the chromaticity of the illumination has a color difference from the white light, a colored image of the measured object cannot be accurately obtained, so that edge detection cannot be performed. That is, it is extremely important in precise measurement to control the applied current to the red, green, and blue LEDs to accurately control the illuminance and chromaticity of the combined illumination.
[0008]
[Problems to be solved by the invention]
However, since the light emitting diodes have individual differences between products, there is a problem that the illuminance differs for each individual even when an applied current having the same value is applied as specified. FIGS. 14 (A), (B) and FIG. 15 show the relationship between the applied current value and the illuminance when the red LED, the green LED, and the blue LED respectively emit light for each lighting device. For example, in the illuminance characteristics of the red LED in FIG. 14A, as the applied current increases, the illuminance increases in all the devices. However, as can be seen from a comparison between the

devices

1 and 4, where the applied current value is high, The difference in illuminance is very large. The same applies to the green LED of FIG. 14B and the blue LED of FIG. That is, since the applied current value for causing light emission at a predetermined illuminance is different for each solid, the applied current value cannot be immediately defined just because the illuminance is specified.
When the applied current value is applied in accordance with the standard, the illuminance of each light emitting diode shifts, and there is a problem that the illuminance does not become the indicated value even in the combined illumination. Further, if the illuminance of each light emitting diode is shifted, the chromaticity of the combined illumination is also shifted.
[0009]
Furthermore, the luminescent chromaticity of the light emitting diode has individual characteristics for each product, and the luminescent chromaticity changes in correlation with the luminous intensity. FIGS. 16, 17, and 18 show the relationship between the illuminance and the chromaticity when the red LED, the green LED, and the blue LED emit light, respectively, for each lighting device.
For example, FIG. 18A shows the x coordinate of the chromaticity of the blue LED for each lighting device. In this figure, it can be seen that the color coordinates change according to the change in the illuminance. Further, it can be seen that the chromaticity differs depending on each lighting device. This is the same for the red LED and the green LED from FIGS.
That is, since the chromaticity of light emission is different for each product, there is a problem that when the mixture ratio for synthesizing a predetermined combined illumination is determined according to the standard, the chromaticity of the combined illumination is different from the indicated value. .
[0010]
In order to realize the illuminance of the combined illumination while paying attention to the difference of the illuminance characteristics for each solid, if the applied current value is changed by adjusting the light emission intensity of each light emitting diode, the illuminance is certainly accurate. However, in this case, when the illuminance is changed, the chromaticity also changes, so that there is a problem that the chromaticity of the combined illumination is shifted.
Conversely, even if the color mixture ratio of the light-emitting diode that realizes the chromaticity of the combined illumination is determined by focusing on the chromaticity, the luminescent chromaticity differs for each solid, and the luminescent chromaticity also changes with the illuminance. Therefore, since the chromaticity of the light emitting diode is not uniquely determined, it is not possible to simply determine the mixture ratio for synthesizing the predetermined chromaticity.
[0011]
SUMMARY OF THE INVENTION It is an object of the present invention to solve a conventional problem and to provide a lighting device control method, a lighting device control program, and a recording device for recording a lighting device control program capable of illuminating a combined illumination having a predetermined illuminance and a predetermined chromaticity. It is to provide a medium, a lighting device and a measuring machine.
[0012]
[Means for Solving the Problems]
The illumination device control method according to claim 1, wherein a plurality of light sources emitting different emission colors, an applied current control means for controlling an applied current to each of the light sources, and an instruction value for instructing illumination illuminance are input. A lighting device provided with an input unit for performing lighting, and synthesizing each illumination from each of the light-emitting light sources to generate a combined illumination having the illuminance designated by the designated value and a predetermined chromaticity. A light source characteristic measuring step of measuring illuminance and chromaticity with respect to the applied current value for each of the light emitting light sources, and a chromaticity change corresponding to the illuminance change of the light emitting light source measured in the light source characteristic measuring step, and Using a theoretical formula for calculating a mixture ratio of the intensities of the respective colors necessary for synthesizing a composite color of a predetermined chromaticity from a color of a different chromaticity, a synthetic illumination having a predetermined chromaticity at the illuminance indicated by the indicated value is used. Synthesize A mixing ratio calculating step of calculating a mixing ratio of light emission illuminance from each of the light emission light sources necessary for generating the illuminance indicated by the indicated value from the mixture ratio calculated in the mixing ratio calculation step. The illuminance calculation step of calculating the illuminance of each of the light-emitting light sources, and the applied current value required to cause each of the light-emitting light sources to emit light at the illuminance calculated in the illuminance calculation step is obtained in the light source characteristic measurement step. Reading an applied current value from the characteristics of the light emitting light source.
[0013]
According to such a configuration, different emission colors are combined to generate a combined color having the designated illuminance and a predetermined chromaticity.
In the light source characteristic measuring step, the relationship between the illuminance and the chromaticity with respect to the applied current value is examined by changing the applied current value for each light emitting light source. Since light-emitting light sources have individual differences due to quality errors, the illuminance and chromaticity differ for each individual even at the same applied current value, and when the illuminance changes, the chromaticity also changes. Check it out.
[0014]
In the mixing ratio calculation step, when calculating the mixing ratio, which is the emission intensity ratio of each light source for generating a composite color having a predetermined chromaticity at the designated illuminance, the characteristics of each light source for each light source are considered. I do. Then, when the illuminance changes, the chromaticity also changes. However, the mixing ratio is determined while sequentially checking whether or not the predetermined chromaticity can be synthesized using the theoretical formula.
The required illuminance of each light-emitting light source is obtained from the obtained mixture ratio, and further, an applied current value for emitting light at this illuminance is obtained. Then, when this applied current value is applied to each light emitting light source, it is possible to generate a combined illumination having a predetermined chromaticity with the designated illuminance.
[0015]
The lighting device control method according to claim 2 is the lighting device control method according to claim 1, wherein the mixture ratio calculating step is initially set to a first temporary mixture ratio having a predetermined ratio as the mixture ratio. A first tentative mixing ratio setting step, and a tentative illuminance calculating step of calculating the illuminance of each of the light emitting sources required to generate the illuminance indicated by the indicated value under the first tentative mixing ratio A chromaticity reading step of reading the chromaticity of each of the light emitting light sources in the illuminance of each of the light emitting light sources calculated in the temporary illuminance calculating step from the measurement result in the light source characteristic measuring step; and A second temporary mixing ratio calculated based on the theoretical formula as a second temporary mixing ratio, which is a mixing ratio of the emission intensities of the respective light emitting sources required to generate the predetermined chromaticity of the combined illumination with the read chromaticity. Calculating the first temporary mixture ratio and the A temporary mixing ratio comparing step of comparing the temporary mixing ratio with the temporary mixing ratio, and a temporary mixing ratio resetting step of resetting the second temporary mixing ratio again as the first temporary mixing ratio in accordance with the comparison result in the temporary mixing ratio comparing step. And a step.
[0016]
In such a configuration, the first temporary mixing ratio is initially set, and the illuminance of each light-emitting light source for synthesizing the illuminance specified under the first temporary mixing ratio is calculated. When each light source is caused to emit light at this illuminance, the illuminance of the composite color becomes the specified illuminance, but the chromaticity does not always have a predetermined value. Therefore, in the chromaticity reading step, the chromaticity corresponding to the illuminance of each light emitting light source is read from the characteristics of the light emitting light source. Then, a mixing ratio for synthesizing a predetermined chromaticity with this chromaticity is obtained as a second mixing ratio according to the color synthesis theory. If the chromaticity is constant even if the illuminance changes, it should be possible to synthesize a composite color of a predetermined chromaticity with the mixture ratio determined by this color synthesis theory. If the second temporary mixing ratio greatly deviates from the first temporary mixing ratio due to the change, it is considered that the predetermined chromaticity cannot be synthesized with the second temporary mixing ratio.
[0017]
Therefore, the first temporary mixing ratio is compared with the second temporary mixing ratio, and if the difference between the two is outside the allowable range, the second temporary mixing ratio is reset to the first temporary mixing ratio. Then, the calculation is repeated until the difference between the first temporary mixture ratio and the second temporary mixture ratio converges within an allowable range.
In this way, by repeating the calculation based on the color composition theory in consideration of the characteristics of the light emitting light source until the calculation result converges to an allowable range, the specified illuminance can be obtained regardless of the non-linear change of the chromaticity due to the illuminance change. It is possible to calculate a mixture ratio for generating a synthesized color having a predetermined chromaticity, and to converge an error between a theoretical value based on color synthesis theory and an actual chromaticity.
[0018]
The lighting device control method according to claim 3 is the lighting device control method according to claim 2, wherein after the light source characteristic measuring step, an average chromaticity calculating step of calculating an average value of chromaticity of the light emitting light source; A representative mixing ratio calculating step of calculating the mixing ratio of the light emitting light sources that generate the predetermined chromaticity of the combined illumination based on the average chromaticity calculated in the average chromaticity calculating step as a representative mixing ratio by the theoretical formula; Wherein the first temporary mixing ratio in the first temporary mixing ratio setting step is the representative mixing ratio.
[0019]
According to such a configuration, an average value of the chromaticity of the light-emitting light sources is obtained for each light-emitting light source, and the mixture ratio for generating a predetermined chromaticity by color synthesis theory using the average value of the chromaticity is represented. Determine as a mixing ratio. Then, this representative mixing ratio is initially set as a first temporary mixing ratio as a first temporary mixing ratio.
The calculation based on the theoretical color synthesis formula is performed until the difference between the first temporary mixing ratio and the second temporary mixing ratio converges to an allowable range. From the beginning, the first temporary mixing ratio and the second temporary mixing ratio are close values. Needless to say, it is desirable that the number of repetitions be reduced. Therefore, starting from the representative mixture ratio calculated based on the average value of chromaticity rather than setting the appropriate ratio as the first temporary mixture ratio, the convergence is fast because the result is close to the final result, and the calculation can be completed quickly. Can be.
[0020]
A lighting device control method according to a fourth aspect is the lighting device control method according to any one of the first to third aspects, wherein the applied current value read in the applied current value reading step is actually verified. Verification step, and a correction step of correcting the applied current value based on the verification result in the verification step, wherein the verification step is performed according to the applied current value read in the applied current value reading step. A verification measurement step of applying an applied current to each light emitting light source and measuring the chromaticity of the combined illumination turned on at this time, and a verification comparing the chromaticity measured in the verification measurement step with a target predetermined chromaticity A comparing step, and a chromaticity correction amount storing step of storing, as a chromaticity correction amount, a chromaticity difference between the chromaticity measured from the comparison result of the verification comparing step and a target predetermined chromaticity; Is the mixing ratio calculation And calculates the mixing ratio a predetermined chromaticity of the target in determining said mixing ratio is shifted by the amount of the chromaticity correction by the theoretical formula in.
[0021]
According to such a configuration, there is an error between the theoretical calculation result and the actual result. However, by verifying and correcting the error, it is possible to accurately synthesize a synthesized color having a predetermined chromaticity at the actually designated illuminance. it can.
A composite color is synthesized with the applied current value obtained theoretically, and the chromaticity of the composite color is actually measured. At this time, an error between the target predetermined chromaticity and the actual value is obtained as a chromaticity correction amount. Then, when applying the color synthesis theory, if the target value of the calculation is set in consideration of the chromaticity correction amount, the difference between the theory and the actual value is filled, and the chromaticity of the actual composite color is set as the target value. A predetermined chromaticity can be obtained.
[0022]
A lighting device control method according to a fifth aspect is the lighting device control method according to any one of the first to fourth aspects, wherein the applied current value read in the applied current value reading step corresponds to the designated value. And storing the applied current value and the specified value as a table in which the applied current value and the specified value are associated with each other.
[0023]
According to such a configuration, since a table recording the relationship between the indicated value and the applied current value is prepared, when the illuminance is indicated by the indicated value, it is possible to immediately read out the applied current value from the table. The composite color can be illuminated. Also, in the case of various chromaticities, if the relationship between the indicated value and the applied current value is stored as a table, it is possible to illuminate the composite color of the various chromaticities with the specified illuminance.
[0024]
A lighting device control method according to claim 6 is the lighting device control method according to any one of claims 1 to 5, wherein the light emitting light source includes a light emitting diode.
[0025]
According to such a configuration, since the light-emitting diode requires a small current value for light emission, the current consumption of the lighting device can be reduced.
Further, it is preferable that the light emitting light source has at least three basic colors of a red LED (light emitting diode), a green LED, and a blue LED. This is because all colors can be synthesized by mixing red, green, and blue. Alternatively, a light emitting diode of another emission color such as yellow, purple, or blue-green may be further provided.
[0026]
The illuminating device control program according to claim 7, wherein the plurality of illuminating light sources that emit different luminescent colors, the current applied to each of the illuminating light sources is controlled, and the illuminating lights from the respective illuminating light sources are combined to generate a predetermined illuminance and A computer is incorporated in an illumination device including an applied current control unit that generates a synthetic illumination having chromaticity, and an input unit that inputs an instruction value for instructing the illuminance of the illumination. A light source characteristic measuring step of measuring illuminance and chromaticity with respect to an applied current value, a chromaticity change corresponding to an illuminance change of the light emitting light source measured in the light source characteristic measuring step, and a predetermined color from a plurality of different chromaticity colors And a theoretical formula for calculating the mixing ratio of the intensities of the respective colors necessary for synthesizing the composite colors of the degrees, the synthetic illumination having the predetermined chromaticity at the illuminance indicated by the indicated value is used. A mixing ratio calculating step of calculating a mixing ratio of light emission intensities from the respective light emitting light sources, and the respective light emissions for generating the illuminance indicated by the indicated value from the mixing ratio calculated in the mixing ratio calculating step. An illuminance calculation step of calculating the illuminance of the light source, and the applied current value required to cause each of the luminescent light sources to emit light at the illuminance calculated in the illuminance calculation step, of the luminescent light source obtained in the light source characteristic measuring step. And reading an applied current value read from the characteristic.
[0027]
The recording medium according to claim 8, wherein a plurality of light sources emitting different emission colors, a current applied to each light source is controlled, and each illumination from each light source is combined to obtain a predetermined illuminance and chromaticity. A computer is incorporated in a lighting device including an applied current control unit that generates a synthetic illumination having: and an input unit that inputs an instruction value for instructing the illuminance of illumination. A light source characteristic measuring step of measuring illuminance and chromaticity with respect to the value, a chromaticity change corresponding to the illuminance change of the light emitting light source measured in the light source characteristic measuring step, and a predetermined chromaticity from a plurality of different chromaticity colors A theoretical formula for calculating a mixing ratio of the intensities of the respective colors necessary for synthesizing the synthetic colors, and the respective light emission necessary for synthesizing the synthetic illumination having the predetermined chromaticity at the illuminance indicated by the indicated value using the theoretical expression A mixing ratio calculating step of calculating a mixing ratio of the emission intensity from the source, and the illuminance of each of the light-emitting light sources for generating the illuminance indicated by the indicated value from the mixing ratio calculated in the mixing ratio calculating step. An illuminance calculation step for calculating, and an application for reading the applied current value necessary for causing each of the light-emitting light sources to emit light at the illuminance calculated in the illuminance calculation step, from the characteristics of the light-emitting light source obtained in the light source characteristic measurement step. A lighting device control program for executing the current value reading step and the current value reading step is recorded.
[0028]
According to such a configuration, the same operation and effect as the first aspect can be obtained. Furthermore, if a computer having a CPU (Central Processing Unit) and a memory (storage device) is incorporated and a program is configured to cause this computer to execute each step, parameters in each step can be easily changed. Then, the recording medium on which the program is recorded may be directly inserted into the computer, and the program may be installed on the computer.A reading device for reading information on the recording medium may be externally attached to the computer, and the program may be installed on the computer from the reading device. You may. Note that the program may be supplied to a computer via a communication line such as the Internet, a LAN cable, a telephone line or the like or wirelessly and installed.
[0029]
The lighting device according to claim 9, wherein the light source emits light of different colors, an applied current control unit that controls an applied current to each of the light sources, and an input unit that inputs an instruction value for instructing illumination illuminance. Wherein the applied current control means comprises: an illuminance corresponding to the applied current value for each of the light sources; A light source characteristic measuring unit that measures and stores chromaticity, a chromaticity change according to a change in illuminance of the light-emitting light source measured by the light source characteristic measuring unit, and synthesis of a predetermined chromaticity from a plurality of colors having different chromaticities. A theoretical formula for calculating a mixture ratio of the intensities of the respective colors necessary for synthesizing the colors, and the respective light-emitting light sources required for synthesizing a synthetic illumination having a predetermined chromaticity at the illuminance indicated by the indicated value using a theoretical formula Departure from Mixing ratio calculating means for calculating a mixing ratio of intensity, and illuminance calculation for calculating illuminance of each of the light emitting light sources for generating illuminance indicated by the indicated value from the mixing ratio calculated by the mixing ratio calculating means Means, an applied current reading means for reading the applied current value necessary for causing each of the light emitting sources to emit light at the illuminance calculated by the illuminance calculating means, from characteristics of the light emitting light source, and an applied current reading means for reading the applied current value. And a command value / current value table storing means for storing a command value / current value table in which the applied current value corresponds to the command value.
[0030]
According to such a configuration, the same operation and effect as the first aspect can be obtained.
[0031]
The measuring device according to claim 10 irradiates light to an object to be measured, the illumination device according to claim 9, a light receiving sensor that receives light reflected from the object to be measured, and light receiving by the light receiving sensor. Image processing means for obtaining the shape of the object to be measured from the obtained image by image processing.
[0032]
According to such a configuration, the object to be measured is illuminated with illumination of a predetermined chromaticity at the illuminance specified by the illumination device, so that an accurate image of the object to be measured is acquired by the light receiving sensor. Therefore, an accurate shape of the measured object can be obtained by image processing.
[0033]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows an image processing type measuring instrument 1 as a measuring instrument provided with the lighting device of the present invention. The measuring device 1 includes an illumination device 3 that irradiates light to an object (not shown) mounted on a stage 2, an imaging unit 4 that receives light reflected from the object, and an imaging unit 4. Image processing means 5 for measuring the shape of the measured object from the acquired image by image processing. In FIG. 1, an illuminometer 6 for measuring the illuminance and chromaticity of illumination is mounted on the stage 2 instead of the object to be measured.
[0034]
The illumination device 3 includes an epi-illumination device 31 that irradiates illumination light from directly above the object to be measured, and a ring-shaped light beam whose central axis is an optical axis A connecting the object to be measured and the imaging unit 4. A ring illumination device 32 that irradiates the light toward the light source and an illumination control device 33 are provided.
[0035]
The epi-illumination device 31 includes a housing 311, a red LED 391, a green LED 392, and a blue LED 393 as light emitting light sources housed in the housing 311, a lens 312 that collects and combines light from each light source, A dichroic mirror 313 for guiding light from the light source to the lens 312 is provided. Here, the dichroic mirror 313 has a property of transmitting or reflecting according to the wavelength of the light, and selectively transmits or reflects the light emitted from each light source to efficiently reduce the light from each light source. It is often guided to the lens 312 and synthesized. The combined illumination emitted from the epi-illumination device 31 is reflected toward the optical axis A by the mirror 314, and then reflected toward the measured object by the half mirror 315 provided on the optical axis A.
A plurality of red LEDs 391, green LEDs 392, and blue LEDs 393 are provided, respectively, and in the following description, each color group is referred to as a “group”.
[0036]
The ring lighting device 32 includes a ring-shaped housing 321 having the optical axis A as a central axis, a red LED 391, a green LED 392, and a blue LED 393 as light-emitting light sources provided in the housing 321, and light from each light source. It is provided with a reflection mirror 323 that reflects toward the object to be measured and a dichroic mirror 324 that guides light from each light source to the reflection mirror 323. A plurality of light sources of the red LED 391, the green LED 392, and the blue LED 393 are arranged in a ring shape around the optical axis A. The dichroic mirror 324 reflects light from each light source in a direction opposite to the optical axis A side. The reflection mirror 323 reflects the light from the dichroic mirror 324 toward the device under test.
[0037]
As shown in FIG. 2, the illumination control device 33 has an input unit 34 for setting and inputting an instruction value for instructing the illuminance of illumination, and has a relationship between the instruction value and an applied current value to each of the light source groups 391 to 393. It comprises a memory (instruction value / current value table storage means) 35 for storing an instruction value / current value table 36, a driver 37 for applying an applied current to each light source, and a central control unit (CPU) 38. I have. Here, the memory 35, the driver 37, and the CPU 38 constitute an applied current control unit.
[0038]
The input means 34 is constituted by a lever or a button provided facing the outside and provided for manual operation. The instruction value set and input by the input means 34 is sent to the CPU 38.
[0039]
As shown in FIG. 3, the indication value / current value table 36 records the applied current value applied to each of the light emitting diode groups of the red LED group 391, the green LED group 392, and the blue LED group 393 with respect to the indication value. It is a table. The indicated value / current value table 36 calibrates the illuminance characteristics, chromaticity characteristics, and individual differences between products of each of the light emitting diode groups 391 to 393, and uses the illuminance of the indicated indicated value in a predetermined composite color. It is created by calculating the applied current value to be applied to each of the light emitting diode group, the red LED group 391, the green LED group 392, and the blue LED group 393 to illuminate a certain white light. The chromaticity of the composite color is arbitrary, but will be described below as a white composite color of CIE1931 chromaticity coordinates (0.3, 0.3).
The creation of the instruction value / current value table 36 will be described later.
[0040]
The CPU 38 sets the applied current value corresponding to the indicated value from the indicated value / current value table 36 stored in the memory 35 in accordance with the indicated value from the input means 34 to the red LED group 391, the green LED group 392, the blue LED The group 393 is read. The CPU 38 instructs the driver 37 of the read applied current value.
The CPU 38 includes a light source characteristic measuring unit, a mixing ratio calculating unit, an illuminance calculating unit, an applied current reading unit, and the like. The operation of each unit will be described with reference to a flowchart.
[0041]
The driver 37 applies a current to each of the light emitting diode groups 391 to 393 to cause the light emitting diodes to emit light. The driver 37 applies a current to the red LED group 391 and a current to the green LED group 392. It is provided with a green LED driver 372 and a blue LED driver 373 for applying a current to the blue LED group 393. The driver 37 receives a command of an applied current value from the CPU 38 and applies a current to each light emitting diode group from each of the drivers 371 to 373.
[0042]
The imaging unit 4 includes an imaging lens 41 that collects reflected light from an object to be measured, and a CCD camera (charge coupled device) 42 that has an imaging device that captures light from the imaging lens 41. .
[0043]
Next, an instruction value / current value table creation process for creating the instruction value / current value table 36 will be described.
To create the indicated value / current value table 36, a color illuminometer 6 as an illuminance chromaticity sensor for measuring the illuminance and chromaticity of illumination is installed on the stage 2. Illuminance and chromaticity data of the illumination measured by the color illuminometer 6 are transmitted to the CPU 38.
[0044]
The instruction value / current value table creation step of creating the instruction value / current value table 36 includes, as shown in the flowchart of FIG. 4, an instruction value / illuminance table creation step ST1 of setting illumination illuminance for the instruction value, and each light emitting diode. A basic data preparation step ST2 for acquiring the characteristics of the illuminance and chromaticity of the group as basic data, and an instruction value based on the characteristics of each of the light emitting diode groups 391 to 393 acquired in the basic data preparation step ST2. An instruction value / current value temporary table creating step ST3 for creating an instruction value / current value temporary table representing a relationship with an applied current value required to generate a predetermined combined color with the given illuminance; A verification step ST4 for verifying the temporary table and a correction step ST7 for correcting the indicated value / current value temporary table based on the verification result in the verification step ST4 are provided. It has been made.
These steps are programmed, and the above-described steps are processed by the CPU 38 executing the programming.
[0045]
The instruction value / illuminance table creation step ST1 will be described.
The relationship between the indicated value [%] and the illuminance [Lx] is as follows. When the indicated value is plotted on the horizontal axis and the illuminance is plotted on the vertical axis, the illuminance is determined corresponding to the indicated value, for example, as shown in FIG. Is represented by a control curve. This relationship may be stored in the CPU 38 in advance, or may be newly set by the input unit 34. Then, the CPU 38 reads the illuminance corresponding to the indicated value from the control curve, and creates an indicated value / illuminance table in which the illuminance is represented with respect to the indicated value, for example, as shown in FIG. 5B.
[0046]
The basic data preparation step ST2 will be described.
As shown in the flowchart of FIG. 6, the basic data preparation step ST2 is a step ST21 of measuring the relationship between the applied current value and the characteristics of the red LED group 391, and the relationship between the applied current value and the characteristics of the green LED group 392. ST22, a step ST23 of measuring the relationship between the applied current value and the characteristics of the blue LED group 393, and a step of calculating an average value of chromaticity of each of the light emitting diodes 391 to 393 (average chromaticity calculating step) ST24. And a step (representative mixture ratio calculating step) ST25 of obtaining a representative mixture ratio for generating a predetermined composite color, that is, a composite color of CIE1931 chromaticity coordinates (0.3, 0.3), based on the average chromaticity. Have.
[0047]
The measurement ST21 of the relationship between the applied current value and the characteristics of the red LED group 391 will be described.
When examining the characteristics of the red LED group 391, the CPU 38 sends a command to the red LED driver 371 to sequentially increase the applied current from 0. Then, the applied current is applied to the red LED group 391 by the red LED driver 371 in order from 0, and the red LED group 391 emits light according to the applied current value. At this time, the color illuminometer 6 measures the illumination illuminance and chromaticity from the red LED group 391. The measurement result is sent to the CPU 38. The CPU 38 stores the relationship between the applied current value to the red LED group 391 and the illuminance and chromaticity at the applied current. This relationship is recorded in a table as a relationship between the chromaticity (x, y) and the illuminance of the red LED group 391 with respect to the applied current value, for example, as shown in FIG.
[0048]
When the measurement is completed for the red LED group 391 from the current value 0 to the current value in the effective range (for example, 65536 when controlled by 16 bits), the applied current value for the green LED group 392 and the blue LED group 393 is next. Is measured (ST22, ST23), and a table of the relationship between the applied current value and the illuminance and chromaticity in FIG. 7 is created as a measurement result.
The light source characteristic measuring step is constituted by ST21, ST22, and ST23.
[0049]
Next, for each of the light emitting diode groups 391 to 392, an average value of chromaticity is obtained for each group (ST24). That is, the CPU 38 obtains a value obtained by averaging the chromaticity measured at each applied current value for each of the light emitting diode groups 391 to 393. The average value of the chromaticity of each of the light emitting diode groups 391 to 393 is shown in the lowermost column of FIG.
[0050]
Next, a representative mixture ratio is determined (ST25). The representative mixture ratio is a light-emitting diode for synthesizing a composite color of CIE1931 chromaticity coordinates (0.3, 0.3) when the light-emitting chromaticity of each of the light-emitting diodes 391 to 393 is an average chromaticity. It is the emission intensity ratio of the group, the red LED group 391, the green LED group 392, and the blue LED group 393.
[0051]
The mixing ratio for synthesizing an arbitrary synthesized color (x, y, E) is obtained from a formula of color synthesis theory. The color synthesis theory will be described.
The luminescence intensity is represented by E. Also, the CIE value of the red LED group 391 is (x_R, Y_R, E_R), The CIE value of the green LED group 392 is (x_G, Y_G, E_G), The CIE value of the blue LED group 393 is (x_B, Y_B, E_B).
At this time, the composite color (x, y, E) is represented by the following equation.
[0052]
(Equation 1)

[0053]
From (Equation 1), T_R, T_G, T_BSolving for
[0054]
(Equation 2)

[0055]
Accordingly, the intensity of each of the light emitting diode groups 391 to 393 for synthesizing the composite color (x, y, E) is expressed as follows.
[0056]
(Equation 3)

[0057]
The intensity E of each of the light emitting diode groups 391 to 393_R, E_G, E_B, The mixture ratio (r) that combines the chromaticity (x, y) of the combined illumination_R, R_G, R_B) Is required.
[0058]
Then, the average chromaticity of each of the light emitting diode groups 391 to 393 is calculated for the red LED group 391 by (x_Rave, Y_Rave), Green LED group 392 (x_Gave, Y_Gave), The blue LED group 393 (x_Bave, Y_Bave), From (Equation 3), the representative mixture ratio (r) for synthesizing the composite color of the CIE 1931 chromaticity coordinates (0.3, 0.3, 1)_Rave, R_Gave, R_Bave) Is determined by the CPU 38.
[0059]
Next, the instruction value / current value temporary table creation step ST3 will be described.
The instruction value / current value provisional table creation step (FIG. 4, ST3) is, as shown in FIG. 8, a mixing ratio calculating step of calculating a mixing ratio for generating a composite color (0.3, 0.3, Li). ST33, an illuminance calculating step ST34 for calculating the illuminance of each light emitting light source of each of the light emitting diode groups 391 to 393 from the mixture ratio calculated in the mixing ratio calculating step ST33, and calculating each of the light emitting diode groups 391 to 393 in the illuminance calculating step. And a current value reading step (applied current value reading step) ST35 for reading an applied current value to emit light at the given illuminance.
[0060]
In the instruction value / current value temporary table creation step ST3, first, the illuminance Li for the instruction value i is read from the instruction value / illuminance table (FIG. 5B) (ST32). At this time, the counter i of the indicated value i is initially set to zero (ST31). When ST32 to ST35 are completed, the counter i is sequentially incremented by one (ST38), and ST32 to ST35 are performed for all the indicated values i (ST36).
[0061]
The mixing ratio calculation step (ST33) will be described.
As shown in FIG. 9, the mixing ratio calculating step ST33 includes a first temporary mixing ratio setting step ST331 of setting a temporary mixing ratio of the emission intensity of each of the light emitting diode groups 391 to 393 as a first temporary mixing ratio. A temporary illuminance calculation step ST332 for obtaining the illuminance of each of the light emitting diode groups 391 to 393 required to generate the predetermined illuminance of the combined illumination under the first temporary mixture ratio, and each light emission calculated in the temporary illuminance calculation step ST332. A chromaticity reading step ST333 for reading the chromaticity of each of the light emitting diode groups 391 to 393 at the illuminance of the diode groups 391 to 393, and a predetermined chromaticity of the combined illumination is generated by the chromaticity read in the chromaticity reading step ST333. A second temporary mixing ratio calculating step ST334 for calculating the mixing ratio of the light emission intensity of each of the light emitting diode groups 391 to 393 necessary for the second temporary mixing ratio; A temporary mixing ratio comparing step ST335 for comparing the temporary mixing ratio and the second temporary mixing ratio, and the second temporary mixing ratio is reset as the first temporary mixing ratio according to the comparison result in the temporary mixing ratio comparing step ST335. And a provisional mixing ratio resetting step ST338.
[0062]
In the first temporary mixing ratio setting step ST331, first, the first temporary mixing ratio (r) which is the emission intensity ratio of each of the light emitting diode groups 391 to 393 is set._Ri, R_Gi, R_Bi) With the representative mixture ratio (r_Rave, R_Gave, R_Bave) Provisionally.
[0063]
The temporary illuminance calculation step ST332 includes the illuminance (L) of each of the light emitting diode groups 391 to 393 required to generate the illuminance Li of the combined illumination at the first temporary mixing ratio._Ri, L_Gi, L_Bi) Is calculated. Here, the illuminance of each of the light emitting diode groups 391 to 393 is obtained by the following equation.
[0064]
L_Ri= R_RiL_i
L_Gi= R_GiL_i(Equation 4)
L_Bi= R_GiL_i
[0065]
Incidentally, the first temporary mixing ratio is now set to the representative mixing ratio (ST331). The representative mixture ratio is calculated based on the CIE1931 chromaticity coordinates (0.3, 0.3), assuming that the chromaticity of each of the light emitting diode groups 391 to 393 is always constant at the average chromaticity regardless of the luminous intensity. This is set as a mixture ratio for synthesizing a composite color. Therefore, (L_Ri, L_Gi, L_Bi), The light emitting diode groups 391 to 393 emit light._iHowever, since the chromaticity actually changes due to the difference in the luminous intensity, the chromaticity of the combined illumination may not be the CIE1931 chromaticity coordinates (0.3, 0.3). Note the points.
[0066]
In the chromaticity reading step ST333, the illuminance (L) calculated in the temporary illuminance calculating step ST332 is used._Ri, L_Gi, L_Bi), The chromaticity when the light emitting diode groups 391 to 393 emit light is read. In this case, the chromaticity for the illuminance is read from the table of the applied current value, the illuminance, and the chromaticity (FIG. 7) prepared in the basic data preparation step ST2.
For each of the red LED group 391, the green LED group 392, and the blue LED group 393,
Red LED group 391 has illuminance L_RiR = (x_Ri, Y_Ri)
Green LED group 392 has illuminance L_GiG = (x_Gi, Y_Gi)
Blue LED group 393 has illuminance L_BiB = (x_Bi, Y_Bi)
It is assumed that is read.
If the read chromaticity deviates from the average chromaticity, the mixture ratio for combining the chromaticities (0.3, 0.3) of the composite color with this chromaticity is the first temporary mixture ratio. Note that this will deviate from (representative mixture ratio at this stage).
[0067]
The second temporary mixing ratio calculation step ST334 is a mixing ratio for generating the chromaticity of the combined illumination and the CIE1931 chromaticity coordinates (0.3, 0.3) based on the chromaticity read in the chromaticity reading step ST333. To the second temporary mixing ratio (r_Ri’, R_Gi’, R_Bi') Based on the color synthesis theory.
According to (Equation 3), the emission intensity of each of the light emitting diode groups 391 to 393 required to generate the chromaticity (0.3, 0.3) of the combined illumination, that is, E_R, E_G, E_BIs required. Therefore, the second temporary mixing ratio (r_Ri’, R_Gi’, R_Bi’) Is (E_R, E_G, E_B).
[0068]
The temporary mixing ratio comparison step ST335 compares the first temporary mixing ratio with the second temporary mixing ratio. Each component of the first temporary mixing ratio is compared with each component of the second temporary mixing ratio for each component.
Here, in the color synthesis theory, the calculation is performed based on the chromaticity when the light is emitted at the illuminance based on the first temporary mixing ratio, and the second temporary mixing ratio is calculated. , It may not be possible to generate the combined illumination of the CIE1931 chromaticity coordinates (0.3, 0.3) even when the combined illumination is combined at the second temporary mixing ratio. Therefore, in ST338, a repeated convergence process of resetting the second temporary mixture ratio as the first temporary mixture ratio is performed, and the degree of convergence is determined in the temporary mixture ratio comparison step ST335.
[0069]
The temporary mixing ratio comparison step ST335 includes a first temporary mixing ratio (r_Ri, R_Gi, R_Bi) And the second temporary mixing ratio (r_Ri’, R_Gi’, R_Bi′) Is compared with a predetermined amount ε. If the difference between the components is less than the predetermined amount ε (ST336: YES), that is, if the following relational expression 5 is satisfied, the second temporary mixing ratio is set as the temporary mixing ratio for the indicated value i. Here, the predetermined amount ε is a difference between the first temporary mixing ratio and the second temporary mixing ratio such that a change in chromaticity due to a change in illuminance falls within an allowable range.
[0070]
| R_Ri-R_Ri’| <Ε
| R_Gi-R_Gi’| <Ε
| R_Bi-R_Bi′ | <Ε (Equation 5)
[0071]
If the relationship of (Equation 5) is not satisfied (ST336: NO), the second temporary mixing ratio is reset as the first temporary mixing ratio (ST338), and the first temporary mixing ratio and the second temporary mixing ratio are set. ST332 to ST335 are repeated until the ratio converges and satisfies Equation 5.
[0072]
Next, in the illuminance calculation step (FIG. 8, ST34), the illuminance L of the combined illumination is calculated based on the provisional mixture ratio._iOf the light emitting diode groups 391 to 393 (L_Ri, L_Gi, L_Bi). This is obtained according to (Equation 4).
The current value reading step ST35 reads from FIG. 7 an applied current value for causing each of the light emitting diode groups 391 to 393 to emit light at the illuminance calculated in the illuminance calculating step ST34, and applies the applied current of each of the light emitting diode groups 391 to 393 to the designated value i. Store as a value. After performing ST32 to ST35 for all the indicated values i, that is, for all the counters i in the effective range (ST36: YES), the current values of the respective light emitting diodes with respect to the indicated value i are indicated in a table. A temporary value / current value table is set (ST37).
[0073]
Next, a verification step of actually verifying the indicated value / current value provisional table is performed (FIG. 4, ST4). That is, the combined illumination is turned on according to the instruction value / current value provisional table, and it is verified whether the chromaticity of the turned on illumination is at the CIE1931 chromaticity coordinates (0.3, 0.3).
As shown in FIG. 10, the verification step ST4 is a verification measurement step ST41 for turning on the combined illumination to measure chromaticity, and a verification comparison step ST42 for comparing the measured chromaticity with a target predetermined chromaticity. And a chromaticity correction amount storage step ST43 for storing the difference between the chromaticity measured from the comparison result of the verification comparison step ST42 and the target predetermined chromaticity as a chromaticity correction amount.
[0074]
In the verification measurement step ST41, the combined illumination is turned on in accordance with the instruction value / current value provisional table. The illuminance of the combined illumination at this time is arbitrary, and the combined illumination is turned on by designating an appropriate instruction value i. Then, the chromaticity (x_i, Y_i) Is measured.
Here, the designated value / current value provisional table is obtained from the calculation based on the color composition theory so that the chromaticity of the combined illumination is set to the CIE1931 chromaticity coordinates (0.3, 0.3). However, even when the chromaticity of the target combined illumination is set to the CIE1931 chromaticity coordinates (0.3, 0.3) and the color combination theory is applied, the chromaticity between the theoretical value and the actually combined chromaticity is not changed. Misalignment may occur (see FIG. 11).
[0075]
In the verification comparison step ST42, the measured chromaticity and the target chromaticity (0.3, 0.3) are compared with a predetermined allowable amount α for each component. When the difference between the components is less than the predetermined amount α (ST42: YES), that is, when the following relational expression 6 is satisfied, the combined illumination that is turned on according to the instruction value / current value provisional table is within the allowable value. Yes, it is determined that the verification is OK (ST45). Here, the predetermined amount α is a color difference that does not affect the measurement when the object to be measured is image-processed and measured.
[0076]
| X_i−0.3 | <α
| Y_i−0.3 | <α (Equation 6)
[0077]
If the verification result is OK (ST45), the instruction value / current value temporary table is stored as a formal instruction value / current value table (instruction value / current value table storage step, ST6 in FIG. 4).
[0078]
On the other hand, when the relational expression 6 is not satisfied, the difference for each component is stored as the chromaticity correction amount (ST43). That is, the chromaticity correction amount (c_x, C_y) Is represented by the following equation.
c_x= 0.3-x_i
c_y= 0.3-y_i(Equation 7)
Since the chromaticity correction amount is the difference between the chromaticity target in the color synthesis theory and the chromaticity of the actually lit composite color, the chromaticity target in the color synthesis theory is divided by the chromaticity correction amount. By shifting the chromaticity, the chromaticity of the actually lit composite color is considered to match the target value.
[0079]
After storing the chromaticity correction amount, the instruction value / current value temporary table is corrected (ST7 in FIG. 4).
The correction of the instruction value / current value provisional table is shown in the flowchart of FIG. The correction step ST7 is basically the same as the indicated value / current value temporary table creation step ST3, as shown in FIG. 12, and FIG. 12 corresponds to the combination of FIG. 8 and FIG. I have.
In the correction step ST7, when calculating the second temporary mixing ratio based on the color synthesis theory in ST77, the chromaticity correction amount (c) read immediately before (ST76)_x, C_y) (0.3 + c)_x, 0.3 + c_y) Is calculated as the target chromaticity.
In this way, by taking into account the deviation between the color synthesis theory and the actual value as the chromaticity correction amount in advance, the chromaticity of the actually lit composite color can be set as the target chromaticity (see FIG. 13). ).
[0080]
The corrected instruction value / current value provisional table is verified again (ST4 in FIG. 4), and if the verification result is good (ST5: YES), it is stored as a formal instruction value / current value table 36 (ST6).
[0081]
Next, the use and operation of the image processing type measuring instrument 1 will be described.
In measuring an object to be measured by the image processing type measuring device 1, first, the object to be measured is placed on the stage 2. Then, an input value indicating the illuminance of the illumination device 3 is input by the input means 34 (input step). Then, the CPU 38 reads the applied current value to each of the light emitting diode groups 391 to 393 corresponding to the input instruction value from the instruction value / current value table 36, and instructs the driver 37 of the applied current value. When an applied current is applied from the driver 37 to each of the light emitting diode groups 391 to 393, illumination from the epi-illumination device 31 and the ring illumination device 32 is emitted, and white combined illumination is measured at the indicated illuminance. The object is irradiated (light emission step). The reflected light from the object to be measured is imaged by the imaging unit 4, and the shape of the object to be measured is measured from the image captured by the image processing unit 5 by arithmetic processing. The calculation result in the image processing means 5 is displayed on a display device such as a CRT or output from an output device such as a printer.
[0082]
As described above, according to such a configuration, the following effects can be obtained.
(1) In the basic data preparation step ST2, characteristics of each of the light emitting diode groups 391 to 393 are checked, and an applied current value for generating a white composite color with the illuminance indicated by the indicated value is obtained based on the characteristics. . Therefore, even if there is an individual difference between the light emitting diodes, it is possible to irradiate the illuminance and white illumination as instructed on the device under test. As a result, an image of the device under test can be accurately captured. Further, an image can be obtained regardless of coloring of the measured object.
[0083]
(2) In the mixing ratio calculation step ST33, in consideration of the fact that the chromaticity changes according to the illuminance, the second temporary mixing ratio for generating the predetermined chromaticity calculated by the color synthesis theory is set to the first temporary mixing ratio. The calculation is repeated until the first temporary mixture ratio and the second temporary mixture ratio converge as compared with the ratio. Therefore, the mixture ratio for synthesizing the illumination of the predetermined chromaticity can be accurately obtained.
[0084]
(3) An average chromaticity of each of the light emitting diode groups 391 to 393 is calculated, and a representative mixture ratio for generating a composite color having a predetermined chromaticity is calculated based on the average chromaticity. Then, starting from this representative mixture ratio, the calculation of the mixture ratio calculation step is performed. As a result, the number of repetitions of the calculation in the mixing ratio calculation step ST33 can be reduced, and the mixing ratio can be calculated quickly.
[0085]
(4) In the verification step ST4, the provisional value / current value table obtained based on the color synthesis theory is verified. At this time, if the chromaticity of the actually illuminated combined illumination deviates from the predetermined chromaticity, the amount of the deviation is defined as the chromaticity correction amount. Then, the target value in the color synthesis theory is shifted by the amount of the chromaticity correction to calculate the mixture ratio and perform the correction. Therefore, it is possible to correct the deviation between the theory and the actual, and to accurately generate the combined illumination having the predetermined chromaticity.
[0086]
(5) Since the applied current value corresponding to the indicated value is prepared as the indicated value / current value table 36, when the indicated value is indicated by the input means 34, it is merely read from the indicated value / current value table 36. Therefore, the response to the change of the indicated value can be promptly performed.
[0087]
It should be noted that the present invention is not limited only to the above-described embodiment, and it is needless to say that various changes can be made without departing from the gist of the present invention.
An example in which the applied current value is obtained in advance for all the indicated values and stored as the indicated value / current value table 36 has been described. Processing such as calculation of the mixture ratio, calculation of the illuminance, and reading of the applied current value may be sequentially performed.
[0088]
The example in which the verification step ST4 is performed after the instruction value / current value table 36 is created has been described. However, the verification is performed immediately after the applied current value for one arbitrary instruction value is obtained, and the chromaticity correction amount is calculated. Then, the instruction value / current value table 36 may be created in consideration of the chromaticity correction amount. Alternatively, when the chromaticity correction amount is known in advance for each of the

lighting devices

31 and 32, the indication value / current value table 36 is calculated from the beginning by applying the color synthesis theory in consideration of the chromaticity correction amount. May be created.
[0089]
The case where the predetermined chromaticity is the CIE1931 chromaticity coordinates (0.3, 0.3) has been described, but the target predetermined chromaticity is, of course, arbitrary. By preparing the instruction value / current value table 36 for each chromaticity of the various types of combined illumination, it is possible to generate the combined illumination of various types of chromaticity with the specified illuminance.
[0090]
The light emitting light source is not particularly limited to the light emitting diode, and the color of the light emitting diode may be yellow, purple, or the like in addition to red, green, and blue. It goes without saying that by applying the present invention, a composite color having a predetermined chromaticity can be synthesized with the designated illuminance even if there are many types of colors of the light emitting light source.
[0091]
【The invention's effect】
As described above, according to the illumination device control method, the illumination device control program, the recording medium on which the illumination device control program is recorded, and the measuring device of the present invention, the combined illumination having the predetermined illuminance and the predetermined chromaticity is illuminated. It is possible to achieve an excellent effect of being able to do so.
[Brief description of the drawings]
FIG. 1 is a diagram showing an image processing type measuring instrument as one embodiment of the present invention.
FIG. 2 is a diagram showing a configuration of a lighting control device in the embodiment.
FIG. 3 is a diagram showing an instruction value / current value table in the embodiment.
FIG. 4 is a flowchart showing an instruction value / current value table creation process for creating the instruction value / current value table of FIG. 3;
FIG. 5A is a diagram showing a control curve for setting a relationship between an instruction value and illuminance. (B) is a figure showing a table of an indication value and illuminance.
FIG. 6 is a flowchart showing a basic data preparation step.
FIG. 7 is a diagram illustrating characteristics of each light emitting light source group with respect to an applied current value.
FIG. 8 is a flowchart showing an instruction value / current value temporary table creation process.
FIG. 9 is a flowchart illustrating a mixture ratio calculating step.
FIG. 10 is a flowchart illustrating a verification process.
FIG. 11 is a diagram showing a deviation between a theoretical value and an actual value.
FIG. 12 is a flowchart illustrating a correction process.
FIG. 13 is a diagram showing illuminance and chromaticity in combined illumination after correction.
FIG. 14A is a diagram illustrating a relationship between an applied current value of a red LED group and illuminance for each lighting device. (B) is a diagram showing the relationship between the applied current value of the green LED group and the illuminance for each lighting device.
FIG. 15 is a diagram illustrating a relationship between an applied current value of a blue LED group and illuminance for each lighting device.
FIG. 16 is a diagram showing a relationship between illuminance and chromaticity of a red LED group for each lighting device.
FIG. 17 is a diagram illustrating a relationship between illuminance and chromaticity of a green LED group for each lighting device.
FIG. 18 is a diagram illustrating a relationship between illuminance and chromaticity of a blue LED group for each lighting device.
[Explanation of symbols]
1 Image processing type measuring machine
3 Lighting device
4 Imaging means
5 Image processing means
6 Illuminometer
31 Epi-illumination device
32 ring lighting system
33 Lighting control device
34 input means
35 memory
36 Indicated value / current value table
37 Driver
38 Central control unit
391 Red LED group
392 Green LED group
393 Blue LED group

Claims

A lighting device comprising: a plurality of light emitting sources that emit different emission colors; an applied current control unit that controls an applied current to each of the light emitting sources; and an input unit that inputs an instruction value for instructing illumination illuminance. A lighting device control method for generating a combined illumination having the illuminance indicated by the indicated value and a predetermined chromaticity by synthesizing the respective illuminations from the respective light emitting sources.
A light source characteristic measuring step of measuring illuminance and chromaticity with respect to the applied current value for each of the light emitting light sources,
Chromaticity change according to the illuminance change of the light emitting light source measured in the light source characteristic measuring step, and mixing of the intensity of each color necessary to synthesize a composite color of a predetermined chromaticity from a plurality of different chromaticity colors A mixing ratio calculating step of calculating a mixing ratio of emission intensities from the respective light emitting sources required for synthesizing a combined illumination having a predetermined chromaticity at the illuminance indicated by the indicated value, using a theoretical formula for calculating a ratio. When,
An illuminance calculation step of calculating the illuminance of each of the light emitting light sources to generate the illuminance indicated by the indicated value from the mixture ratio calculated in the mixture ratio calculation step,
An applied current value reading step of reading the applied current value required to cause each of the light emitting sources to emit light at the illuminance calculated in the illuminance calculating step from the characteristics of the light emitting light source obtained in the light source characteristic measuring step, A lighting device control method, comprising:

The lighting device control method according to claim 1,
The mixing ratio calculation step,
A first temporary mixing ratio setting step of initially setting a first temporary mixing ratio having a predetermined ratio as the mixing ratio;
A temporary illuminance calculation step of calculating the illuminance of each of the light-emitting sources required to generate the illuminance indicated by the indicated value under the first temporary mixing ratio;
A chromaticity reading step of reading the chromaticity of each of the respective light emitting light sources in the illuminance of each of the light emitting light sources calculated in the temporary illuminance calculating step from the measurement result in the light source characteristic measuring step;
Based on the theoretical formula, a mixing ratio of the light emission intensities of the respective light emitting sources required to generate the predetermined chromaticity of the combined illumination with the chromaticity read in the chromaticity reading step is set as a second temporary mixing ratio. A second temporary mixing ratio calculating step of
A temporary mixing ratio comparing step of comparing the first temporary mixing ratio and the second temporary mixing ratio,
A temporary mixing ratio resetting step of resetting the second temporary mixing ratio again as the first temporary mixing ratio according to the comparison result in the temporary mixing ratio comparing step. Control method.

The lighting device control method according to claim 2,
After the light source characteristic measuring step, an average chromaticity calculating step of obtaining an average value of chromaticity for the light emitting light source,
A representative mixing ratio calculating step of calculating the mixing ratio of the light emitting light sources that generate the predetermined chromaticity of the combined illumination based on the average chromaticity calculated in the average chromaticity calculating step as a representative mixing ratio by the theoretical formula; With
The lighting device control method according to claim 1, wherein the first temporary mixing ratio in the first temporary mixing ratio setting step is the representative mixing ratio.

The lighting device control method according to any one of claims 1 to 3,
A verification step of actually verifying the applied current value read in the applied current value reading step, and a correction step of correcting the applied current value based on a verification result in the verification step;
The verification step includes:
A verification measurement step of applying an applied current to each of the light emitting sources according to the applied current value read in the applied current value reading step, and measuring the chromaticity of the combined illumination that is turned on at this time,
A verification comparison step of comparing the chromaticity measured in the verification measurement step with a target predetermined chromaticity,
A chromaticity correction amount storage step of storing a chromaticity difference between the chromaticity measured from the comparison result of the verification comparison step and the target predetermined chromaticity as a chromaticity correction amount,
The correction step calculates the mixture ratio by shifting a predetermined chromaticity to be targeted when calculating the mixture ratio by the theoretical formula in the mixture ratio calculation step by the chromaticity correction amount. Lighting device control method.

The lighting device control method according to any one of claims 1 to 4,
An instruction value / current value table storing step of storing the applied current value read in the applied current value reading step in association with the indicated value, and storing the applied current value and the indicated value as a table in association with the indicated value; A lighting device control method, comprising:

The lighting device control method according to any one of claims 1 to 5,
The lighting device control method, wherein the light emitting light source includes a light emitting diode.

A plurality of light emitting sources that emit different emission colors, and an applied current control that controls an applied current to each of the light emitting sources and combines the illuminations from each of the light emitting sources to generate a combined illumination having a predetermined illuminance and chromaticity. Means and an input device for inputting an instruction value for instructing the illuminance of the illumination, incorporating a computer into the illumination device, this computer,
A light source characteristic measuring step of measuring illuminance and chromaticity with respect to the applied current value for each of the light emitting light sources,
A chromaticity change corresponding to the illuminance change of the light emitting light source measured in the light source characteristic measuring step, and a mixing ratio of the intensity of each color necessary for synthesizing a composite color of a predetermined chromaticity from a plurality of different chromaticity colors. And a theoretical formula for calculating the mixture ratio, and calculating a mixture ratio of emission intensities from the respective light emission sources required to synthesize a combined illumination having a predetermined chromaticity at the illuminance indicated by the indicated value using the indicated ratio. When,
An illuminance calculation step of calculating the illuminance of each of the light emitting light sources to generate the illuminance indicated by the indicated value from the mixture ratio calculated in the mixture ratio calculation step,
An applied current value reading step of reading the applied current value required to cause each of the light emitting sources to emit light at the illuminance calculated in the illuminance calculating step from the characteristics of the light emitting light source obtained in the light source characteristic measuring step, A lighting device control program characterized by being executed.

A plurality of light emitting sources that emit different emission colors, and an applied current control that controls an applied current to each of the light emitting sources and combines the illuminations from each of the light emitting sources to generate a combined illumination having a predetermined illuminance and chromaticity. Means and an input device for inputting an instruction value for instructing the illuminance of the illumination, incorporating a computer into the illumination device, this computer,
A light source characteristic measuring step of measuring illuminance and chromaticity with respect to the applied current value for each of the light emitting light sources,
A chromaticity change corresponding to the illuminance change of the light emitting light source measured in the light source characteristic measuring step, and a mixing ratio of the intensity of each color necessary for synthesizing a composite color of a predetermined chromaticity from a plurality of different chromaticity colors. And a theoretical formula for calculating the mixture ratio, and calculating a mixture ratio of emission intensities from the respective light emission sources required to synthesize a combined illumination having a predetermined chromaticity at the illuminance indicated by the indicated value using the indicated ratio. When,
An illuminance calculation step of calculating the illuminance of each of the light emitting light sources to generate the illuminance indicated by the indicated value from the mixture ratio calculated in the mixture ratio calculation step,
An applied current value reading step of reading the applied current value required to cause each of the light emitting sources to emit light at the illuminance calculated in the illuminance calculating step from the characteristics of the light emitting light source obtained in the light source characteristic measuring step, A computer-readable recording medium recording a lighting device control program to be executed.

A light-emitting light source that emits a different light-emitting color; an applied current control unit that controls an applied current to each of the light-emitting light sources; and an input unit that inputs an instruction value that instructs illumination illuminance. An illumination device that combines illumination to generate a combined illumination having a predetermined illuminance and chromaticity,
The applied current control means,
Light source characteristic measuring means for measuring and storing illuminance and chromaticity with respect to the applied current value for each light emitting light source,
A mixing ratio of a chromaticity change corresponding to a change in illuminance of the light emitting light source measured by the light source characteristic measuring unit and an intensity of each color necessary for synthesizing a composite color of a predetermined chromaticity from a plurality of different chromaticity colors. And a mixing ratio calculating means for calculating a mixing ratio of the emission intensities from the respective light emitting sources necessary for synthesizing the combined illumination having a predetermined chromaticity at the illuminance indicated by the indicated value using the theoretical formula for calculating When,
Illuminance calculation means for calculating the illuminance of each of the light emitting light sources for generating the illuminance indicated by the indicated value from the mixture ratio calculated by the mixture ratio calculation means,
An applied current reading unit that reads the applied current value necessary for causing each of the light emitting sources to emit light at the illuminance calculated by the illuminance calculating unit from characteristics of the light emitting light source;
An illumination device comprising: an instruction value / current value table storage unit that stores an instruction value / current value table in which the applied current value read by the applied current reading unit corresponds to the instruction value. .

The illumination device according to claim 9, which irradiates light to the device under test,
A light-receiving sensor that receives reflected light from the object to be measured,
A measuring device comprising: an image processing unit that obtains a shape of the object by image processing from an image received by the light receiving sensor.