JP4141627B2 - Information acquisition method, image capturing apparatus, and image processing apparatus - Google Patents

Description

すなわち、
【数２】

となる。
【００２６】
また、
【数３】

であるので、
【数４】

となる。また、
【数５】

であり、Ｌ_１２、θ_１は既知の値であるので、θ_２はＬの関数で与えられる。すなわち、
【数６】

となる。よって、
【数７】

となる。ここで、Ｄ１、Ｄ_２、Ｐ_１、Ｐ_２、θ_１は、計測値又は既知の値であるので、上の式の未知数はθ_０及びＬの２つである。したがって上の条件を満たす（θ_０、Ｌ）の組み合わせを求めることができる。すなわち、被測定部２２までの距離Ｌを仮定した場合、仮定した距離Ｌに対応する被測定部の面傾きθ_０を算出することができる。また、被測定部の近傍２４についても、同様に被測定部の近傍２４までの距離Ｌ’と被測定部の近傍２４の面傾きθ_０’の組み合わせを求めることができる。
【００２７】
本発明は、物体２０の被測定部２２までの距離Ｌと被測定部２２の面傾きθ_０との組み合わせと、物体２０の被測定部の近傍２４までの距離Ｌ’と被測定部の近傍２４の面傾きθ_０’との組み合わせに基づいて、被測定部２２までの距離Ｌ及び面傾きθ_０を算出する。以下、算出方法について詳細に説明する。
【００２８】
図２は、被測定部２２までの距離Ｌ、被測定部２２の面傾きθ_０を算出する方法の一例の説明図である。まず、被測定部２２までの距離ＬをＬａと仮定する。図１に関連して説明した数式に基づいて、仮定した距離Ｌａに対応する被測定部２２の面傾きθ_０を算出する。次に、算出した面傾きθ_０によって定まる被測定部２２の面を延長し、被測定部の近傍２４からの反射光の光路と交わる点に、被測定部の近傍２４が存在すると仮定した場合の被測定部の近傍２４までの仮の距離Ｌｂを算出する。このとき被測定部の近傍２４までの仮の距離Ｌｂは、カメラ１０と被測定部２２までの仮の距離Ｌａ、被測定部２２からの反射光の入射角θ_１、被測定部の近傍２４からの反射光の入射角θ_１’及び、被測定部２２の面傾きθ_０に基づいて幾何的に算出することができる。
【００２９】
次に、算出した仮の距離Ｌｂに対応する、被測定部の近傍２４の面傾きθ_０’を算出する。面傾きθ_０’は、図１に関連して説明した数式により算出することができる。物体２０の被測定部２２と被測定部の近傍２４との間隔は、微小であるので、被測定部２２と被測定部の近傍２４の面傾きはほぼ同一となる。したがって、算出した面傾きθ_０とθ_０’とを比較することにより、最初に仮定した被測定部２２までの距離Ｌａが正しい値であるかを判定することができる。すなわち、面傾きθ_０とθ_０’との差が所定の範囲内であれば、仮定した距離Ｌａを被測定部２２までの距離Ｌとすることができる。
【００３０】
また、面傾きθ_０とθ_０’との差が所定の範囲内に無い場合は、最初に仮定した距離Ｌａの設定に誤りがあったとして、被測定部２２までの距離Ｌを他の値に設定して同様の計算を行えばよい。図１に関連して説明した数式を満たす、被測定部２２までの距離Ｌが、上限値を有することは明らかであり、下限値は零であるので、仮の距離Ｌａについて、有限の範囲において調べればよい。例えば、有限の範囲の距離Ｌａについて２分探索法によって、被測定部２２までの真の距離Ｌを抽出してよい。また、仮の距離Ｌａについて、有限の範囲で所定の距離間隔でθ_０、θ_０’の差を算出し、真の距離Ｌを抽出してもよい。また、仮の距離Ｌａについて、複数の値についてθ_０、θ_０’の差を算出し、差が最小となる仮の距離Ｌａを真の距離Ｌとしてもよい。また、被測定部の面傾き情報は、被測定部までの距離情報に基づいて、図１に関連して説明した数式によって算出することができる。また、図１に関連して説明した数式によって被測定部の表面反射率情報も算出することができる。
【００３１】
図３は、仮の距離Ｌａについての所定の範囲で所定の距離間隔で、面傾きθ_０及び面傾きθ_０’を算出した結果の一例を示す。図３のグラフにおいて、横軸は、被測定部２２までの仮の距離Ｌａを示し、縦軸は被測定部２２及び被測定部の近傍２４の面傾きを示す。本例において、物体２０の被測定部２２までの距離Ｌを２００ｍｍ、被測定部２２の面傾きを０度とした。また、照射位置１２と照射位置１４との距離を１０ｍｍ、θ_１を２０度、仮の距離Ｌａの間隔を１０ｍｍとして計算を行った。
【００３２】
データ１０２は、横軸に示される仮の距離Ｌａに対応する被測定部２２の面傾きを示し、データ１０４は、被測定部の近傍２４の面傾きを示す。仮の距離２００ｍｍにおいて、被測定部２２及び被測定部の近傍２４の面傾きが０度で一致する。
【００３３】
図４は、本発明に係る画像撮像装置１００の構成の一例を示す。画像撮像装置１００は、照射部４０、分光部５０、制御部６０、撮像部７０及び、画像処理装置３００を備える。照射部４０は、光学的に異なる２点の照射位置から、物体２０に光を照射する。照射部４０は、２点の照射位置のそれぞれに光源を有し、それぞれの光源から物体２０に光を照射してよく、また、照射部４０は、一つの光源を有し、一つの光源を照射位置（１２，１４）のそれぞれに移動させて物体２０に光を照射してもよい。照射部４０が、２点の照射位置のそれぞれに光源を有する場合、それぞれの照射位置において異なる波長の光を物体２０に実質的に同時に照射してよい。分光部５０は、異なる波長の光による物体２０からの反射光を、異なる波長のそれぞれを主要な波長成分とする光に分離する。撮像部７０は、２点の照射位置のいずれか一つと光学的に同位置において、２点の照射位置から照射された光による物体２０における光の反射光を撮像する。撮像部７０は、分光部５０によって分離された光のそれぞれを撮像してもよい。制御部６０は、それぞれの照射位置において、照射部４０が光を照射する発光タイミング及び、撮像部７０が反射光を撮像する撮像タイミングを同期させる。
【００３４】
画像処理装置３００は、撮像部７０において撮像された物体２０の被測定部２２からの反射光及び被測定部の近傍２４からの反射光に基づいて、被測定部２２までの距離情報を算出する。画像処理装置３００は、入力部８０、記憶部９０、算出部１１０及び、出力部１２０を備える。入力部８０は、２点の照射位置から照射されたそれぞれの光の、物体２０によるそれぞれの反射光に基づく画像データを入力する。記憶部９０は、入力部８０に入力された画像データを記憶する。記憶部９０は、照射部４０が照射した光の波長特性毎に画像データを記憶してもよい。
【００３５】
算出部１１０は、記憶部９０に記憶された画像データに基づいて、物体２０の被測定部２２までの距離情報、物体２０の被測定部２２の面傾き情報を算出する。算出部１１０は、被測定部２２からの反射光の強度及び反射光の入射角に基づいて、被測定部までの仮の距離情報を仮定した場合に、被測定部２２の面傾き情報を算出する第１算出手段と、被測定部２２までの仮の距離情報及び、被測定部２２の面傾き情報に基づいて、被測定部の近傍２４の仮の距離情報を算出する第２算出段階と、被測定部の近傍２４の仮の距離情報と、被測定部の近傍２４からの反射光の強度及び、反射光の入射角に基づいて、被測定部の近傍２４の面傾き情報を算出する第３算出手段と、被測定部の面傾き情報と、被測定部の近傍２４の面傾き情報との誤差を算出する第４算出手段とを有する。算出部１１０は、第４算出手段において算出した誤差が所定の範囲内である場合に、被測定部２２の仮の距離情報を、被測定部２２の真の距離情報として出力部１２０及び記憶部９０に出力する。
【００３６】
第４算出手段は、被測定部２２の複数の仮の距離情報に対して、それぞれ誤差を算出し、算出部１１０は、誤差が最小となる場合の被測定部２２の仮の距離情報を真の被測定部２２の距離情報としてよい。また、第２算出手段は、被測定部２２の面傾き情報に基づいて、被測定部２２の面を延長した近傍において、被測定部の近傍２４の仮の距離を算出してよい。
【００３７】
また、算出部１１０は、画像データに基づいて、反射光の強度を撮像部７０の画素単位又は画素領域単位で検出し、検出した反射光の強度に基づいて、物体２０までの距離情報の分布及び面傾き情報を算出してもよい。また、算出部１１０は、距離情報の分布及び面傾き情報の分布に基づいて物体２０の三次元情報を算出してもよい。算出部１１０は、図１から図３に関連して説明した方法と同様又は同一の方法で被測定部２２の各情報及び物体２０の各情報の分布を算出してもよい。また、照射部４０が異なる波長の光を照射した場合、算出部１１０は、図６に関連して説明した方法によって、それぞれの照射位置から同一の波長の光を照射したときの、反射光の強度を算出し、算出した強度に基づいて被測定部２２の各情報及び物体２０の各情報の分布を算出することが好ましい。記憶部９０は、算出部１１０が算出した被測定部２２の各情報及び、物体２０の各情報の分布を記憶することが好ましい。
【００３８】
出力部１２０は、算出部１１０が算出した、物体２０の被測定部２２までの距離情報、被測定部２２の面傾き情報及び、物体２０における各情報の分布を出力する。出力部１２０は、被測定部２２の各情報及び物体２０の各情報の分布を、表示装置上に数値及び図形を用いて表示してよい。また、出力部１２０は、被測定部２２の各情報及び物体２０の各情報の分布を音によって出力してもよい。出力部１２０は、予め指定された位置情報に基づいて各情報を出力してもよい。また、出力部１２０は、予め指定された項目及び基準に基づいて出力してもよい。例えば、予め指定された項目が一定以上となる領域について各情報を出力してもよい。また、出力部１２０は、物体２０が静止しているか動いているかに基づいて各情報を出力してもよい。
【００３９】
また、入力部８０は、被測定部２２からの反射光及び被測定部の近傍の複数の場所からの反射光に基づく画像データが入力され、算出部１１０の第４算出手段は、被測定部の近傍の複数の場所において、被測定部２２の仮の面傾き情報と被測定部の近傍の仮の面傾き情報との誤差をそれぞれ算出し、算出部１１０は、誤差の二乗和が最小となる場合の被測定部２２の仮の面傾き情報を真の被測定部２２の距離情報としてもよい。
【００４０】
また、本例において、画像撮像装置１００は、分光部５０を備えているが、照射部４０がそれぞれの照射位置で異なるタイミングで光を照射する場合は、画像撮像装置１００は分光部５０を備えず、撮像部７０は、照射部４０が光を照射したタイミングに基づくタイミングで、それぞれの照射位置から照射された光による反射光をそれぞれ撮像してもよい。
【００４１】
図５は、撮像部７０が撮像した物体２０からの反射光に基づく画像データ１５０の一例を示す。物体２０は、微小距離で面傾きが急激に変化するエッジ１５６を有する。算出部１１０は、物体２０からの反射光に基づく画像データ１５０に基づいて、物体のエッジを検出し、被測定部の近傍の複数の場所の内、物体２０のエッジを境界として物体２０の画像データを複数の領域に分割した領域の、被測定部２２のデータが有る領域と同じ領域に前記データが有る、被測定部の近傍２４の場所の仮の面傾き情報に基づいて被測定部２２の距離情報を算出する。例えば、図５に示すように、物体２０の画像データが１５０が、エッジ１５６を境界とした領域１５２と領域１５４とを有する場合、算出部１１０は、被測定部２２のデータが存在する領域１５２の中にある、被測定部の近傍２４の面傾き情報に基づいて被測定部２２の距離情報を算出する。
【００４２】
また、算出部１１０は、被測定部の近傍の複数の場所の内、被測定部２２からの反射光の強度と被測定部の近傍からの反射光の強度との差が所定の範囲内にある、被測定部の近傍の場所の仮の面傾き情報に基づいて被測定部２２の距離情報を算出してもよい。
【００４３】
図６は、画像撮像装置１００の一例を説明する図である。図６において図４と同じ符号を付したものは図４に関連して説明したものと同一又は同様の機能及び構成を有してよい。照射部４０は、光学的に異なる２点の照射位置（１２，１４）から、物体２０にそれぞれ異なる波長の光を実質的に同時に物体２０に照射する。例えば、照射部４０は、それぞれ異なる波長の光を主に透過する光学フィルター（図示せず）を有していてもよい。このとき、照射部４０はそれぞれの照射位置（１２，１４）から照射される光を光学フィルターを介して、波長λ_ａ、λ_ｂの光として物体２０に実質的に同時に照射する。
【００４４】
照射部４０から照射された光は、物体２０で反射し、光学レンズ５２に入射する。光学レンズ５２に入射した物体２０からの反射光は、光学レンズ５２を介して分光部５０に入射される。
【００４５】
分光部５０は、一例として光学レンズ５２が結像した反射光を偏向する偏向子、偏向された光の偏向方向を波長に応じて回転させるリターダ、偏向方向の異なる光を分割するプリズムを有する。分光部５０によって分光された光はそれぞれ撮像部（７０ａ、７０ｂ）に受光される。撮像部（７０ａ、７０ｂ）は、一例として２板の固体撮像素子である。撮像部（７０ａ、７０ｂ）に受光された光は、光電効果により電荷として読み出され、Ａ／Ｄ変換器（図示せず）によりデジタル電気信号に変換され、画像処理装置３００に入力される。画像処理装置３００は、入力された信号に基づいて物体２０までの距離情報、物体２０の表面の傾き情報、物体２０の表面の反射率情報を算出する。
【００４６】
撮像部７０は、分光部５０によって分離された光のそれぞれを撮像する。撮像部７０は、一例として固体撮像素子であり、物体２０の像は、固体撮像素子の受光面上に結像される。結像された物体２０の像の光量に応じ、固体撮像素子の各センサエレメントに電荷が蓄積され、蓄積された電荷は、一定の順序で走査され、電気信号として読み出される。固体撮像素子は、物体２０からの反射光の強度を画素単位に高い精度で検出可能なように、信号／雑音比が良く、画素数が大きい電荷結合素子（ＣＣＤ）イメージセンサであることが好ましい。固体撮像素子としてＣＣＤ以外にＭＯＳイメージセンサ、Ｃｄ−Ｓｅ密着型イメージセンサ、ａＳｉ密着型イメージセンサ、又はバイポーラ密着型イメージセンサ等を用いてもよい。
【００４７】
制御部６０は、照射部４０が光を照射する発光タイミング及び、撮像部７０が反射光を撮像する撮像タイミングを制御する。制御部４０は、同期信号が入力され、同期信号に基づいて発光タイミング及び撮像タイミングを制御する。また、制御部６０は、物体２０までの距離情報に基づいて、照射部４０が照射する光の強度、撮像部７０のフォーカス、絞り等を制御してもよい。制御部６０は、撮像部７０の露光時間を制御してもよい。
【００４８】
本例においては、照射部４０は、２点の照射位置においてそれぞれ一つの波長を主な波長成分とする光を照射したが、他の例においては、照射部４０は２点の照射位置のそれぞれで、複数の波長を主な波長成分とする光を照射してもよい。このとき、分光部５０は、物体２０からの反射光を、照射部４０が照射した光の複数の波長のそれぞれの波長成分に分割することが好ましい。しかし、全ての波長成分に分割する場合、分光部５０が大きくなりすぎる場合がある。そこでさらに他の例においては、照射部４０は、照射位置１２において、波長λ_ａを主要な波長成分とする光を照射し、照射位置１４において、２種類の波長を主要な波長成分とし、２種類の波長の平均値が波長λ_ａとなるような光を照射してもよい。このとき、分光部５０は、物体２０による反射光を、それぞれの照射位置から照射された光の波長成分に分割する。つまり、分光部５０は、反射光を２種類の光に分割する。画像処理装置３００は、照射位置１２から照射された光の反射光強度と、照射位置１４から照射された光の反射光強度の１／２とに基づいて、物体２０の各情報を算出する。
【００４９】
本例において、分光部５０はプリズムを有していたが、他の例においては、異なる波長の光のそれぞれを主に透過する複数の光学フィルターを有してもよい。光学フィルターは、撮像部７０の受光面に配置される。また、照射部４０がそれぞれの照射位置で同時に光を照射しないときは、撮像部７０は、分光部５０を介さずに反射光を撮像してよい。
【００５０】
図７は、照射位置（１２，１４）から照射する光の波長の一例を示す。本例においては、照射位置１２からλａを主要な波長成分とする光を照射し、照射位置１２からλｂ及びλｃの２つの波長を主要な波長成分とする光を照射する。また、照射位置１２から照射される光による物体２０からの反射光の強度をＷとし、照射位置１４から照射される光のうち、波長λｂを成分とする光による物体２０からの反射光の強度をＷｂ、波長λｃを成分とする光による物体２０からの反射光の強度をＷｃとする。この場合、分光部５０は、物体２０からの反射光を、波長λａを主要な波長成分とする光と、波長λａ及びλｂを主要な波長成分とする光に分割する。分光部５０は、例えば光学フィルターを用いて物体２０からの反射光を分割してよい。
【００５１】
図７（ａ）に示すように、波長λｂと波長λｃの平均値がλａとなるような光を照射位置１４から照射した場合、波長λｂを成分とする光による反射光の強度Ｗｂと、波長λｃを成分とする光による反射光の強度Ｗｃとの平均値Ｗａを算出することにより、照射位置１４から波長λａの光を照射した場合における物体２０からの反射光の強度を算出することができる。つまり、反射光を分割するための光学フィルター等の減衰を考慮にいれた反射光強度について、照射位置１４から照射された波長λｂ及びλｃを主要な波長成分とする光による反射光の強度の１／２を算出することで、照射位置１４から波長λａの光を照射した場合における物体２０からの反射光の強度を算出することができる。
【００５２】
また、図７（ｂ）に示すように、波長λｂと波長λｃを成分とする光による反射光の強度を線形近似することにより、照射位置１４から波長λａの光を照射した場合における物体２０からの反射光の強度を算出してもよい。本例において説明したように、それぞれの照射位置において異なる波長の光を物体２０に照射し、物体２０からの反射光を分光部５０により波長分離し、撮像することにより、２点の照射位置から照射された光による反射光のそれぞれを、同時に撮像することができるので、物体２０が動いている場合においても、物体２０までの距離情報、面傾き情報を算出することができる。また、図７においては、照射位置１４から２つの波長成分を主要な波長成分とする光を照射したが、他の例においては、さらに多くの波長を主要な波長成分とする光を物体２０に照射してもよい。
【００５３】
図８は、画像処理装置３００の一例を示す。画像処理装置３００は、図４に関連して説明した画像処理装置３００と、同一又は同様の機能及び構成を有してよい。本例において、入力部８０、記録部９０、出力部１２０は、図４に関連して説明したものと同一又は同様の機能及び構成を有する。
【００５４】
算出部１１０は、ＣＰＵ８２、入力装置８８，ＲＯＭ８４、ハードディスク９２，ＲＡＭ８６、ＣＤ−ＲＯＭドライブ９４を有する。ＣＰＵ８２は、ＲＯＭ８４及びＲＡＭ８６に格納されたプログラムに基づいて動作する。キーボード、マウス等の入力装置８８を介して利用者によりデータが入力される。ハードディスク９２は、画像等のデータ、及びＣＰＵ８２を動作させるプログラムを格納する。ＣＤ−ＲＯＭドライブ９４はＣＤ−ＲＯＭ９６からデータ又はプログラムを読みとり、ＲＡＭ８６、ハードディスク９２及びＣＰＵ８２の少なくともいずれかに提供する。
【００５５】
ＣＰＵ８２が実行するプログラムの機能構成は、図４に関連して説明した画像処理装置３００の算出部１１０の機能構成と同じであり、２点の照射位置から物体２０に光を照射した場合の、それぞれの照射位置からの光による物体２０からの反射光の強度を、それぞれ入力させる入力モジュールと、反射光のそれぞれの強度に基づいて、物体２０までの距離情報を算出させる算出モジュールとを有する。入力モジュール及び算出モジュールが、ＣＰＵ８２に行わせる処理は、図４に関連して説明した算出部１１０の機能及び動作と同じであるから、説明を省略する。これらのプログラムは、ＣＤ−ＲＯＭ８４等の記録媒体に格納された利用者に提供される。記録媒体の一例としてのＣＤ−ＲＯＭ９６には、本出願で説明した、画像処理装置３００の動作の一部又は全ての機能を格納することができる。
【００５６】
上記のプログラムは、記録媒体から直接ＲＡＭ８６に読み出されてＣＰＵ８２により実行されてもよい。あるいは、上記のプログラムは、記録媒体からハードディスク（ＭＤ）等の磁気記録媒体、ＭＯ等の光磁気記録媒体、テープ状記録媒体、不揮発性の半導体メモリカード等を用いることができる。
【００５７】
上記のプログラムは、単一の記録媒体に格納されてもよいし、複数の記録媒体に分割されて格納されてもよい。また、上記プログラムは、記録媒体に圧縮されて格納されてもよい。圧縮されたプログラムは伸張され、ＲＡＭ８６等の別の記録媒体に読み出され、実行されてもよい。さらに、圧縮されたプログラムは、ＣＰＵ８２によって伸張され、ハードディスク９２等にインストールされた後、ＲＡＭ８６等の別の記録媒体に読み出され、実行されてもよい。
【００５８】
さらに、記録媒体の一例としてのＣＤ−ＲＯＭ９６は、通信ネットワークを介して、ホストコンピュータによって提供される上記のプログラムを格納してもよい。記録媒体に格納された上記のプログラムは、ホストコンピュータのハードディスクに格納され、通信ネットワークを介してホストコンピュータから当該コンピュータに送信され、ＲＡＭ８６等の別の記録媒体に読み出され、実行されてもよい。
【００５９】
上記のプログラムを格納した記録媒体は、本出願の画像処理装置３００を製造するためにのみ使用されるものであり、そのような記録媒体の行としての製造及び販売等が本出願に基づく特許険の侵害を構成することは明らかである。
【００６０】
図９は、本発明に係る情報獲得方法のフローチャートの一例を示す。本発明に係る情報獲得方法は、光学的に異なる２点の照射位置から、物体に光を照射する照射段階と、２点の照射位置から照射された光による物体からの反射光をそれぞれ撮像する撮像段階と、光学的に異なる２点の照射位置から、物体に光を照射する角度のうちいずれかを算出する角度算出段階と、撮像位置において撮像された、物体の被測定部の反射光及び、被測定部の近傍からの反射光に基づいて、被測定部までの距離情報を算出する算出段階とを備える。本例においては、撮像段階は、２点の照射位置のいずれかと光学的に同位置である撮像位置において、２点の照射位置から照射された光による物体からの反射光をそれぞれ撮像し、角度測定段階は、撮像段階が撮像する物体からの反射光に基づいて光を照射する角度を算出する。
【００６１】
算出段階は、撮像段階において撮像された、被測定部からの反射光の強度及び被測定部の近傍からの反射光の強度に基づいて、被測定部の距離情報及び被測定部の面傾き情報を算出してもよい。以下フローチャートを用いて算出段階における、被測定部までの距離情報を算出する方法について説明する。
【００６２】
算出段階はまず、第１算出段階において、被測定部からの反射光の強度及び反射光の入射角に基づいて、被測定部までの仮の距離情報を仮定する（Ｓ１００）。つぎに、仮定した距離情報に基づいて、被測定部の面傾き情報を算出する（Ｓ１０２）。仮定した距離情報に基づいて被測定部の面傾き情報を算出する方法は、図１から図３に関連して説明した方法と同一又は同様の方法で算出してよい。
【００６３】
次に、第２算出段階において、被測定部までの仮の距離情報及び、被測定部の面傾き情報に基づいて、被測定部の近傍の仮の距離情報を算出する（Ｓ１０４）。被測定部の近傍の仮の距離情報を算出する方法は、図１から図３に関連して説明した方法と同一又は同様の方法で算出してよい。
【００６４】
次に第３算出段階において、被測定部の近傍の仮の距離情報と、被測定部の近傍からの反射光の強度及び、反射光の入射角に基づいて、被測定部の近傍の面傾き情報を算出する（Ｓ１０６）。被測定部の近傍の面傾き情報を算出する方法は、図１から図３に関連して説明した方法と同一又は同様の方法で算出してよい。
【００６５】
次に第４算出段階において、被測定部の面傾き情報と、被測定部の近傍の面傾き情報との誤差を算出する（Ｓ１０８）。算出した誤差が、所定の範囲内であるか否かを判定し（Ｓ１１０）、算出した誤差が所定の範囲内である場合に、被測定部の仮の距離情報を、被測定部の真の距離情報として出力する（Ｓ１１２）。また、算出した誤差が所定の範囲外である場合は、被測定部の仮の距離情報を他の値として第１算出段階に戻る。つまり、被測定部の複数の仮の距離情報に対して、Ｓ１００からＳ１１０までの計算を行い、第４算出段階は、被測定部の複数の仮の距離情報に対して、それぞれ誤差を算出し、算出段階は、誤差が最小となる場合の被測定部の仮の距離情報を真の前記被測定部の距離情報としてもよい。算出した距離情報に基づいて、被測定部の面傾き情報を算出することができる。
【００６６】
図２に関連して説明した方法と同様に、第２算出段階は、被測定部の面傾き情報に基づいて、被測定部の面を延長した近傍において、被測定部の近傍の仮の距離情報を算出してもよい。また、撮像段階は、被測定部からの反射光及び、被測定部の近傍の複数の場所からの反射光を撮像し、第４算出段階は、被測定部の近傍の複数の場所において、被測定部の仮の面傾き情報と被測定部の近傍の仮の面傾き情報との誤差をそれぞれ算出し、算出段階は、誤差の二乗和が最小となる場合の被測定部の仮の距離情報を真の被測定部の距離情報としてもよい。被測定部の近傍の複数の場所からの反射光から得られる画像データに基づいて、フローチャートで説明した計算を行うことにより、ノイズや計算誤差を低減した被測定部までの距離情報を得ることができる。
【００６７】
照射段階は、それぞれの照射位置において、異なる波長の光を物体の被測定部及び被測定部の近傍に照射し、それぞれの照射位置において、実質的に同時に物体に光を照射し、撮像段階は、異なる波長の光のそれぞれを選択的に透過させる波長選択手段を有し、それぞれの照射位置における光による物体からの反射光をそれぞれ撮像してもよい。
【００６８】
図８に関連して説明した情報獲得方法においては、図１から図３に関連して説明した方法と同一又は同様の方法で、被測定部までの距離情報及び面傾き情報を算出してよい。
【００６９】
以上、本発明を実施の形態を用いて説明したが、本発明の技術的範囲は上記実施の形態に記載の範囲には限定されない。上記実施の形態に、多様な変更又は改良を加えることが可能であることが当業者に明らかである。その様な変更又は改良を加えた形態も本発明の技術的範囲に含まれ得ることが、特許請求の範囲の記載から明らかである。
【００７０】
【発明の効果】
上記説明から明らかなように、本発明によれば、光が照射された物体から得られる反射光を撮像することにより、物体の表面の傾きによる誤差を排除した、物体までの距離情報を獲得することが可能となる。また、物体２０の表面の傾き情報、物体２０の表面の反射率情報を獲得することが可能となる。
【図面の簡単な説明】
【図１】 本発明の原理説明図である。
【図２】 被測定部２２までの距離Ｌ、被測定部２２の面傾きθ_０を算出する方法の一例の説明図である。
【図３】 仮の距離Ｌａについての所定の範囲で所定の距離間隔で、面傾きθ_０及び面傾きθ_０’を算出した結果の一例を示す。
【図４】 本発明に係る画像撮像装置１００の構成の一例を示す。
【図５】 撮像部７０が撮像した物体２０からの反射光に基づく画像データ１５０の一例を示す。
【図６】 画像撮像装置１００の一例を説明する図である。
【図７】 照射位置（１２，１４）から照射する光の波長の一例を示す。
【図８】 画像処理装置３００の一例を示す。
【図９】 本発明に係る情報獲得方法のフローチャートの一例を示す。
【符号の説明】
１０・・・カメラ、１２、１４・・・照射位置
２０・・・物体、２２・・・被測定部
２４・・・被測定部の近傍、４０・・・照射部
５０・・・分光部、５２・・・光学レンズ
６０・・・制御部、７０・・・撮像部
８０・・・入力部、８２・・・ＣＰＵ
８４・・・ＲＯＭ、８６・・・ＲＡＭ
８８・・・入力装置、９２・・・ハードディスク
９４・・・ＣＤ−ＲＯＭドライブ、９６・・・ＣＤ−ＲＯＭ
９０・・・記憶部、１００・・・画像撮像装置
１１０・・・算出部、１２０・・・出力部
１５０・・・画像データ、３００・・・画像処理装置[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an information acquisition method, an image capturing apparatus, and an image processing apparatus that acquire information related to the depth distance of an object, the tilt of the object surface, and the reflectance of the object surface. In particular, the present invention relates to an information acquisition method, an image imaging apparatus, and an image processing apparatus that capture an image of reflected light obtained from an object irradiated with light and acquire information about the object.
[0002]
[Prior art]
In order to obtain distance information to an object and position information of an object, a method of 3D image measurement is known in which pattern light such as a slit or stripe pattern is projected onto the object, and the pattern projected onto the object is photographed and analyzed. It has been. Typical measurement methods include the slit light projection method (also known as the light shredding method), the coded pattern light projection method, etc., and is well-known for “Three-dimensional image measurement” by Seiji Iguchi and Kosuke Sato (Shokendo).
[0003]
Japanese Patent Application Laid-Open No. 61-155909 (publication date: July 15, 1986) and Japanese Patent Application Laid-Open No. 63-23312 (publication date: September 29, 1988) disclose light from different light source positions to an object. A distance measuring device and a distance measuring method for measuring the distance to an object based on the intensity ratio of the reflected and reflected light from the object are disclosed.
[0004]
Japanese Laid-Open Patent Publication No. 62-46207 (published on February 28, 1987) irradiates an object with two lights having different phases, and based on the phase difference of reflected light from the object, the distance to the object A distance detection device for measuring the above is disclosed.
[0005]
Hebei et al., “Development of AXi-Vision Camera 3D Imager” (3D Image Conference 99, 1999) adds ultra-high-speed intensity modulation to projected light, and accelerates objects illuminated with intensity-modulated light at high speed. A method is disclosed in which a distance is measured from a degree of intensity modulation that is taken by a camera having a shutter function and changes depending on the distance to an object.
[0006]
Japanese Patent Application Laid-Open No. 10-48336 and Japanese Patent Application Laid-Open No. 11-94520 disclose that an object is formed by projecting different light patterns having different wavelength characteristics onto an object and extracting a wavelength component of incident light from the object. A real-time range finder for calculating the distance to is disclosed.
[0007]
[Problems to be solved by the invention]
In the conventional distance measuring device and distance measuring method, the distance information is measured by irradiating the object to be measured and measuring the reflected light, but the inclination of the surface of the object to be measured is not considered. It was. For this reason, even in the case of an object at the same distance, the measurement intensity of the reflected light differs depending on the inclination of the surface, resulting in an error in distance measurement.
[0008]
In addition, the distance detection device disclosed in Japanese Patent Laid-Open No. 62-46207 requires a highly accurate phase detector for detecting a phase difference, which makes the device expensive and lacks simplicity. In addition, since the phase of the emitted light from the point of the subject is measured, the depth distribution of the entire subject cannot be measured.
[0009]
Moreover, the distance measurement method using intensity modulation disclosed in “Development of Axi-Vision Camera 3D Imaging Device” (3D Image Conference 99, 1999) performs intensity increase / decrease modulation with the same light source. Therefore, it is necessary to perform light modulation at a very high speed, and it has not been possible to measure easily.
[0010]
[Means for Solving the Problems]
In order to solve the above problems, in the first embodiment of the present invention, there is provided an information acquisition method for acquiring distance information to an object, wherein the object is irradiated with light from two optically different irradiation positions. One of an irradiation stage, an imaging stage for imaging reflected light from an object by light irradiated from two irradiation positions, and an angle at which light is irradiated to the object from two optically different irradiation positions An angle calculation step for calculating the distance, and a calculation step for calculating distance information to the measured portion based on the reflected light of the measured portion of the object and the reflected light from the vicinity of the measured portion captured at the imaging position An information acquisition method is provided.
[0011]
In the imaging stage, the reflected light from the object by the light emitted from the two irradiation positions is respectively imaged at the imaging position that is optically the same as one of the two irradiation positions. The angle at which the light is irradiated may be calculated based on the reflected light from the object to be imaged. In addition, the calculation stage is based on the distance information of the measured part and the surface of the measured part based on the intensity of the reflected light from the measured part and the intensity of the reflected light from the vicinity of the measured part. Tilt information may be calculated. In addition, the calculation step calculates the surface tilt information of the measured part when assuming temporary distance information to the measured part based on the intensity of the reflected light from the measured part and the incident angle of the reflected light. A first calculation stage, a second calculation stage for calculating temporary distance information in the vicinity of the part to be measured based on provisional distance information to the part to be measured and surface inclination information of the part to be measured, A third calculation step of calculating surface inclination information in the vicinity of the measured part based on the temporary distance information in the vicinity of the part, the intensity of the reflected light from the vicinity of the measured part, and the incident angle of the reflected light; A fourth calculation stage for calculating an error between the surface inclination information of the part to be measured and the surface inclination information in the vicinity of the part to be measured, and if the error is within a predetermined range, The distance information may be output as the true distance information of the part to be measured.
[0012]
In the fourth calculation stage, an error is calculated for each of a plurality of provisional distance information of the part to be measured, and in the calculation stage, the provisional distance information of the part to be measured when the error is minimized is measured as a true measurement. It is good also as the distance information of a part. In the second calculation step, temporary distance information in the vicinity of the measurement target may be calculated in the vicinity of the surface of the measurement target extended based on the surface inclination information of the measurement target. In the imaging stage, reflected light from the part to be measured and reflected light from a plurality of places in the vicinity of the part to be measured are imaged. In the fourth calculation stage, the part to be measured is taken in a plurality of places in the vicinity of the part to be measured. And calculating a temporary distance information of the measured part when the sum of squares of the error is minimized. The distance information of the true part to be measured may be used.
[0013]
The irradiation stage irradiates light of different wavelengths to the measured part of the object and the vicinity of the measured part at each irradiation position, and irradiates the object substantially simultaneously at each irradiation position. Further, wavelength selection means for selectively transmitting each of light having different wavelengths may be provided, and reflected light from an object by light at each irradiation position may be respectively imaged.
[0014]
In the second embodiment of the present invention, an image capturing apparatus that acquires distance information to an object, an irradiation unit that irradiates light to the object from two optically different irradiation positions, and two irradiations An imaging unit that images the reflected light of an object by light emitted from two irradiation positions at the same optical position as any one of the positions, and reflection of the object to be measured captured by the imaging unit An image processing apparatus that calculates distance information to the measurement unit based on light and reflected light from the vicinity of the measurement unit;
An image pickup apparatus is provided.
[0015]
You may further provide the control part which synchronizes the light emission timing in which an irradiation part irradiates light in each irradiation position, and the imaging timing in which an imaging part images reflected light. The irradiation unit irradiates light of different wavelengths at each irradiation position, irradiates light to the object substantially simultaneously at each irradiation position, and reflects light reflected by the object of light of different wavelengths to each of different wavelengths. A spectroscopic unit that separates light into main wavelength components may be further provided, and the imaging unit may capture each of the separated lights. The spectroscopic unit may include a plurality of optical filters that mainly transmit light of different wavelengths.
[0016]
According to a third aspect of the present invention, there is provided an image processing apparatus for processing an image obtained by imaging an object, and inputting image data based on reflected light from the object for each light emitted from two irradiation positions. Input unit, storage unit for storing the input image data, distance information to the unit to be measured and surface of the unit to be measured based on the object to be measured of the image data and the data in the vicinity of the unit to be measured Provided is an image processing apparatus comprising: a calculation unit that calculates inclination information; and an output unit that outputs distance information and surface inclination information calculated by the calculation unit.
[0017]
The image data is data captured by an imaging unit having a plurality of pixels that receive reflected light, and the calculation unit extracts the intensity of reflected light of each light emitted from two irradiation positions for each pixel. The distribution of the object distance information and the distribution of the surface inclination information may be calculated based on the intensity of each extracted light to be measured and the reflected light from the vicinity of the measurement target for each pixel. The calculation unit may calculate the three-dimensional information of the object based on the distribution of the distance information and the distribution of the surface inclination information, and the output unit may output the three-dimensional information of the object calculated by the calculation unit.
[0018]
The calculation unit calculates the surface inclination information of the measured part when assuming temporary distance information to the measured part based on the intensity of the reflected light from the measured part and the incident angle of the reflected light. A calculation means, a second calculation means for calculating temporary distance information in the vicinity of the measured part based on the temporary distance information to the measured part and the surface tilt information of the measured part, and the vicinity of the measured part A third calculating means for calculating surface tilt information in the vicinity of the measured part based on the provisional distance information, the intensity of the reflected light from the vicinity of the measured part, and the incident angle of the reflected light, and the measured part And a fourth calculation means for calculating an error between the surface tilt information of the measured portion and the surface tilt information in the vicinity of the measured portion, and if the error is within a predetermined range, the provisional distance information of the measured portion is obtained. Alternatively, it may be output as the true distance information of the part to be measured.
[0019]
The fourth calculating means calculates an error for each of the plurality of provisional distance information of the measurement target, and the calculation unit calculates the provisional distance information of the measurement target when the error is the minimum as a true measurement. It is good also as the distance information of a part. The second calculating means may calculate temporary distance information in the vicinity of the measured part in the vicinity of the extended surface of the measured part based on the surface tilt information of the measured part. The input unit receives image data based on the reflected light from the part to be measured and the reflected light from a plurality of places in the vicinity of the part to be measured, and the fourth calculation means includes a plurality of places in the vicinity of the part to be measured. And calculating the error between the provisional surface inclination information of the measured part and the provisional surface inclination information in the vicinity of the measured part, and the calculating part calculates the provisional information of the measured part when the sum of squares of the error is minimized. This distance information may be the distance information of the true part to be measured.
[0020]
The calculation unit detects the edge of the object based on the image data of the object, and the calculation unit converts the image data of the object into a plurality of regions with the edge of the object as a boundary among a plurality of locations near the measured unit. The distance information of the part to be measured may be calculated based on provisional surface inclination information of a location in the vicinity of the part to be measured, which has data in the same area as the area where the data of the part to be measured exists. Further, the calculation unit has a difference between the intensity of the reflected light from the measured part and the intensity of the reflected light from the vicinity of the measured part in a plurality of locations in the vicinity of the measured part, The distance information of the part to be measured may be calculated based on temporary surface inclination information at a location near the part to be measured.
[0021]
The above summary of the invention does not enumerate all the necessary features of the present invention, and sub-combinations of these feature groups can also be the invention.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described through embodiments of the invention. However, the following embodiments do not limit the invention according to the claims, and all combinations of features described in the embodiments are included. It is not necessarily essential for the solution of the invention.
[0023]
FIG. 1 is an explanatory diagram of the principle of the present invention. The object 20 is irradiated with light of intensities P1 and P2 from the irradiation position 12 and the irradiation position 14, respectively, and the reflected light of each light by the object 20 is imaged by the camera 10. The camera 10 is, for example, a charge coupled device (CCD), has a plurality of pixels, and captures reflected light from the measured portion 22 of the object 20 and the vicinity 24 of the arsenic section in each pixel unit. Each intensity is detected every time. Based on the reflected light imaged by the camera 10, the distance L of the object 20 to the measured portion 22 and the surface inclination θ of the measured portion 22. ₀ And the reflectance R of the surface of the measured part 22 _Obj Is calculated. The irradiation positions (12, 14) may be arranged at arbitrary positions. One of the irradiation angles of light irradiated on the object 20 from the irradiation position (12, 14) is calculated. In this example, the camera 10 is optically connected to any one of the irradiation positions (12, 14). Therefore, the irradiation angle of the light applied to the object 20 is calculated based on the incident angle of the reflected light captured by the camera 10. In this example, the case where the irradiation position 12 and the camera 10 are optically arranged at the same position will be described.
[0024]
As shown in FIG. 1, the irradiation position 14 extends from the irradiation position 12 to L. ₁₂ It is arranged at a distant position. Distance L ₁₂ Is a known value unique to the measurement system. In addition, the angle at which light is irradiated from the irradiation position (12, 14) to the part to be measured 22 of the object 20 is set to θ. ₁ , Θ ₂ The angle at which light is irradiated from the irradiation position (12, 14) to the vicinity 24 of the measured portion of the object 20 is set to θ. ₁ ', Θ ₂ 'And. In addition, since the camera 10 is optically disposed at the same position as the irradiation position 12, the angle at which the reflected light from the measured part 22 is received is θ. _C The angle at which the reflected light from the vicinity 24 of the part to be measured is received is θ _C ' _C = Θ ₁ , Θ _C '= Θ ₁ 'Is. In addition, the distance from the irradiation position 12 to the measured portion 22 is set to L, respectively. ₁ , The distance to the vicinity 24 of the part to be measured is L ₁ 'And the distance from the irradiation position 14 to the part to be measured is L ₂ , The distance to the vicinity 24 of the part to be measured is L ₂ 'And.
[0025]
The intensity of the reflected light from the part to be measured 22 of the light irradiated from the irradiation position (12, 14) is D, respectively. ₁ , D ₂ Then D ₁ , D ₂ Is given as:
[Expression 1]

That is,
[Expression 2]

It becomes.
[0026]
Also,
[Equation 3]

So
[Expression 4]

It becomes. Also,
[Equation 5]

And L ₁₂ , Θ ₁ Is a known value, so θ ₂ Is given by a function of L. That is,
[Formula 6]

It becomes. Therefore,
[Expression 7]

It becomes. Where D1, D ₂ , P ₁ , P ₂ , Θ ₁ Is a measured or known value, so the unknown in the above equation is θ ₀ And L. Therefore, the above condition is satisfied (θ ₀ , L) can be determined. That is, when the distance L to the measured part 22 is assumed, the surface inclination θ of the measured part corresponding to the assumed distance L ₀ Can be calculated. Similarly, the distance L ′ to the vicinity 24 of the measured portion and the surface inclination θ of the vicinity 24 of the measured portion also in the vicinity 24 of the measured portion. ₀ You can ask for a combination of '.
[0027]
In the present invention, the distance L of the object 20 to the measured portion 22 and the surface inclination θ of the measured portion 22 are measured. ₀ And the distance L ′ of the object 20 to the vicinity 24 of the part to be measured and the surface inclination θ of the vicinity 24 of the part to be measured. ₀ Based on the combination with ', the distance L to the measured part 22 and the surface inclination θ ₀ Is calculated. Hereinafter, the calculation method will be described in detail.
[0028]
FIG. 2 shows the distance L to the part to be measured 22 and the surface inclination θ of the part to be measured 22. ₀ It is explanatory drawing of an example of the method of calculating. First, the distance L to the part to be measured 22 is assumed to be La. Based on the mathematical formula described with reference to FIG. 1, the surface inclination θ of the measured portion 22 corresponding to the assumed distance La ₀ Is calculated. Next, the calculated surface inclination θ ₀ The surface of the measured part 22 determined by the above is extended, and it is assumed that the vicinity 24 of the measured part exists at the point where it intersects the optical path of the reflected light from the vicinity 24 of the measured part. A temporary distance Lb is calculated. At this time, the temporary distance Lb to the vicinity 24 of the measured part is the temporary distance La between the camera 10 and the measured part 22 and the incident angle θ of the reflected light from the measured part 22. ₁ , The incident angle θ of the reflected light from the vicinity 24 of the measured part ₁ 'And the surface inclination θ of the measured part 22 ₀ Can be calculated geometrically.
[0029]
Next, the surface inclination θ in the vicinity 24 of the measured portion corresponding to the calculated temporary distance Lb. ₀ 'Is calculated. Face tilt θ ₀ 'Can be calculated by the mathematical formula described with reference to FIG. Since the distance between the measured part 22 of the object 20 and the vicinity 24 of the measured part is very small, the surface inclinations of the measured part 22 and the vicinity 24 of the measured part are substantially the same. Therefore, the calculated surface inclination θ ₀ And θ ₀ By comparing with ', it is possible to determine whether or not the distance La to the measured portion 22 assumed first is a correct value. That is, the surface inclination θ ₀ And θ ₀ If the difference from 'is within a predetermined range, the assumed distance La can be set as the distance L to the measured portion 22.
[0030]
Also, the surface inclination θ ₀ And θ ₀ If the difference from 'is not within the predetermined range, assuming that there is an error in the setting of the initially assumed distance La, the distance L to the measured part 22 is set to another value and the same calculation is performed. Just do it. It is clear that the distance L to the measured part 22 that satisfies the mathematical formula described in relation to FIG. 1 has an upper limit value, and the lower limit value is zero. Therefore, the provisional distance La is in a finite range. Find out. For example, the true distance L to the part to be measured 22 may be extracted by the binary search method for the distance La in a finite range. Further, with respect to the temporary distance La, θ at a predetermined distance interval within a finite range. ₀ , Θ ₀ The difference of 'may be calculated and the true distance L may be extracted. Further, regarding the temporary distance La, θ ₀ , Θ ₀ The difference of 'may be calculated, and the temporary distance La that minimizes the difference may be set as the true distance L. Further, the surface tilt information of the part to be measured can be calculated by the mathematical formula described in relation to FIG. 1 based on the distance information to the part to be measured. In addition, the surface reflectance information of the portion to be measured can be calculated by the mathematical formula described with reference to FIG.
[0031]
FIG. 3 shows a surface inclination θ at a predetermined distance interval within a predetermined range with respect to the provisional distance La. ₀ And surface tilt θ ₀ An example of the result of calculating 'is shown. In the graph of FIG. 3, the horizontal axis indicates the provisional distance La to the measured part 22, and the vertical axis indicates the surface inclination of the measured part 22 and the vicinity 24 of the measured part. In this example, the distance L of the object 20 to the measured part 22 is 200 mm, and the surface inclination of the measured part 22 is 0 degree. Further, the distance between the irradiation position 12 and the irradiation position 14 is 10 mm, θ ₁ Was calculated by setting the distance of the temporary distance La to 10 mm.
[0032]
The data 102 indicates the surface inclination of the measured portion 22 corresponding to the temporary distance La indicated on the horizontal axis, and the data 104 indicates the surface inclination of the vicinity 24 of the measured portion. At a temporary distance of 200 mm, the surface inclinations of the measured portion 22 and the vicinity 24 of the measured portion coincide with each other at 0 degree.
[0033]
FIG. 4 shows an example of the configuration of the image capturing apparatus 100 according to the present invention. The image capturing apparatus 100 includes an irradiation unit 40, a spectroscopic unit 50, a control unit 60, an image capturing unit 70, and an image processing device 300. The irradiation unit 40 irradiates the object 20 with light from two irradiation positions that are optically different. The irradiation unit 40 may have a light source at each of the two irradiation positions, and the object 20 may be irradiated with light from each of the light sources. The irradiation unit 40 may have one light source and one light source. The object 20 may be irradiated with light by moving to each of the irradiation positions (12, 14). When the irradiation unit 40 has a light source at each of the two irradiation positions, the object 20 may be irradiated with light of different wavelengths substantially simultaneously at the respective irradiation positions. The spectroscopic unit 50 separates the reflected light from the object 20 with light of different wavelengths into light having each of the different wavelengths as main wavelength components. The imaging unit 70 captures reflected light of the light from the object 20 by light emitted from the two irradiation positions at the same optical position as any one of the two irradiation positions. The imaging unit 70 may image each of the lights separated by the spectroscopic unit 50. The control unit 60 synchronizes the light emission timing at which the irradiation unit 40 emits light and the imaging timing at which the imaging unit 70 images reflected light at each irradiation position.
[0034]
The image processing apparatus 300 calculates distance information to the measured unit 22 based on the reflected light from the measured unit 22 of the object 20 captured by the imaging unit 70 and the reflected light from the vicinity 24 of the measured unit. . The image processing apparatus 300 includes an input unit 80, a storage unit 90, a calculation unit 110, and an output unit 120. The input unit 80 inputs image data based on each reflected light of the object 20 of each light irradiated from two irradiation positions. The storage unit 90 stores the image data input to the input unit 80. The storage unit 90 may store image data for each wavelength characteristic of light irradiated by the irradiation unit 40.
[0035]
Based on the image data stored in the storage unit 90, the calculation unit 110 calculates distance information of the object 20 to the measured unit 22 and surface tilt information of the measured unit 22 of the object 20. The calculation unit 110 calculates the surface tilt information of the measured part 22 when assuming temporary distance information to the measured part based on the intensity of the reflected light from the measured part 22 and the incident angle of the reflected light. A first calculation unit that calculates the temporary distance information of the vicinity of the measured part based on the temporary distance information to the measured part 22 and the surface inclination information of the measured part 22; Based on the temporary distance information of the vicinity 24 of the part to be measured, the intensity of the reflected light from the vicinity 24 of the part to be measured, and the incident angle of the reflected light, the surface tilt information of the vicinity 24 of the part to be measured is calculated. Third calculation means, and fourth calculation means for calculating an error between the surface inclination information of the part to be measured and the surface inclination information of the vicinity 24 of the part to be measured. When the error calculated by the fourth calculating means is within a predetermined range, the calculation unit 110 outputs the temporary distance information of the measured unit 22 as the true distance information of the measured unit 22 and the output unit 120 and the storage unit. Output to 90.
[0036]
The fourth calculation means calculates an error for each of a plurality of provisional distance information of the measurement target unit 22, and the calculation unit 110 calculates the provisional distance information of the measurement unit 22 when the error is minimum. The distance information of the measured part 22 may be used. Further, the second calculation means may calculate a provisional distance in the vicinity 24 of the measured part in the vicinity of the extended surface of the measured part 22 based on the surface inclination information of the measured part 22.
[0037]
Further, the calculation unit 110 detects the intensity of reflected light in units of pixels or pixel areas of the imaging unit 70 based on the image data, and the distribution of distance information to the object 20 based on the detected intensity of reflected light. In addition, surface tilt information may be calculated. The calculation unit 110 may calculate the three-dimensional information of the object 20 based on the distribution of distance information and the distribution of surface tilt information. The calculation unit 110 may calculate the distribution of each piece of information of the measured unit 22 and each piece of information of the object 20 in the same or the same manner as the method described with reference to FIGS. In addition, when the irradiation unit 40 emits light of different wavelengths, the calculation unit 110 uses the method described in relation to FIG. 6 to reflect the reflected light when the light of the same wavelength is irradiated from each irradiation position. It is preferable to calculate the intensity, and to calculate the distribution of each piece of information of the measured part 22 and each piece of information of the object 20 based on the calculated intensity. The storage unit 90 preferably stores each piece of information of the measurement target 22 calculated by the calculation unit 110 and the distribution of each piece of information of the object 20.
[0038]
The output unit 120 outputs the distance information of the object 20 to the measured unit 22, the surface tilt information of the measured unit 22, and the distribution of each information in the object 20 calculated by the calculating unit 110. The output unit 120 may display each information of the measured unit 22 and each information distribution of the object 20 on the display device using numerical values and figures. In addition, the output unit 120 may output the information of the measured unit 22 and the distribution of the information of the object 20 by sound. The output unit 120 may output each piece of information based on position information designated in advance. Further, the output unit 120 may output based on items and criteria specified in advance. For example, each piece of information may be output for a region in which items designated in advance become a certain level or more. The output unit 120 may output each piece of information based on whether the object 20 is stationary or moving.
[0039]
The input unit 80 receives image data based on the reflected light from the measured unit 22 and the reflected light from a plurality of locations in the vicinity of the measured unit, and the fourth calculating unit of the calculating unit 110 includes the measured unit , And calculates the error between the provisional surface inclination information of the part to be measured 22 and the provisional surface inclination information in the vicinity of the part to be measured, and the calculation unit 110 determines that the sum of squares of errors is the smallest. The provisional surface tilt information of the measured part 22 in this case may be used as the distance information of the true measured part 22.
[0040]
In this example, the image capturing apparatus 100 includes the spectroscopic unit 50. However, when the irradiation unit 40 irradiates light at different irradiation positions, the image capturing apparatus 100 includes the spectroscopic unit 50. Instead, the imaging unit 70 may capture reflected light from the light irradiated from each irradiation position at a timing based on the timing at which the irradiation unit 40 irradiates light.
[0041]
FIG. 5 shows an example of image data 150 based on the reflected light from the object 20 imaged by the imaging unit 70. The object 20 has an edge 156 whose surface inclination changes rapidly at a minute distance. The calculation unit 110 detects the edge of the object based on the image data 150 based on the reflected light from the object 20, and the image of the object 20 with the edge of the object 20 among a plurality of locations in the vicinity of the measurement target as a boundary. Based on the provisional surface tilt information of the location in the vicinity 24 of the measured part where the data is in the same area as the area where the data of the measured part 22 is present in the area obtained by dividing the data into a plurality of areas. The distance information is calculated. For example, as illustrated in FIG. 5, when the image data 150 of the object 20 includes a region 152 and a region 154 with the edge 156 as a boundary, the calculation unit 110 includes a region 152 in which data of the measured unit 22 exists. The distance information of the part to be measured 22 is calculated based on the surface tilt information in the vicinity 24 of the part to be measured.
[0042]
In addition, the calculation unit 110 determines that the difference between the intensity of the reflected light from the part to be measured 22 and the intensity of the reflected light from the vicinity of the part to be measured is within a predetermined range among a plurality of places near the part to be measured. The distance information of the part to be measured 22 may be calculated based on provisional surface tilt information of a location near the part to be measured.
[0043]
FIG. 6 is a diagram illustrating an example of the image capturing apparatus 100. 6 having the same reference numerals as those in FIG. 4 may have the same or similar functions and configurations as those described with reference to FIG. The irradiation unit 40 irradiates the object 20 with light of different wavelengths substantially simultaneously on the object 20 from two irradiation positions (12, 14) that are optically different. For example, the irradiation unit 40 may include an optical filter (not shown) that mainly transmits light having different wavelengths. At this time, the irradiation unit 40 transmits the light irradiated from each irradiation position (12, 14) through the optical filter to the wavelength λ. _a , Λ _b The light is irradiated onto the object 20 substantially simultaneously.
[0044]
The light emitted from the irradiation unit 40 is reflected by the object 20 and enters the optical lens 52. The reflected light from the object 20 that has entered the optical lens 52 enters the spectroscopic unit 50 through the optical lens 52.
[0045]
The spectroscopic unit 50 includes, as an example, a deflector that deflects the reflected light imaged by the optical lens 52, a retarder that rotates the deflection direction of the deflected light according to the wavelength, and a prism that divides light having different deflection directions. The light split by the spectroscopic unit 50 is received by the imaging units (70a, 70b), respectively. The imaging units (70a, 70b) are two-plate solid-state imaging devices as an example. The light received by the imaging units (70a, 70b) is read out as electric charges by the photoelectric effect, converted into a digital electrical signal by an A / D converter (not shown), and input to the image processing apparatus 300. The image processing apparatus 300 calculates distance information to the object 20, inclination information of the surface of the object 20, and reflectance information of the surface of the object 20 based on the input signal.
[0046]
The imaging unit 70 images each of the lights separated by the spectroscopic unit 50. The imaging unit 70 is a solid-state imaging device as an example, and the image of the object 20 is formed on the light receiving surface of the solid-state imaging device. Charges are accumulated in each sensor element of the solid-state imaging device in accordance with the amount of light of the image of the imaged object 20, and the accumulated charges are scanned in a predetermined order and read out as electrical signals. The solid-state imaging device is preferably a charge coupled device (CCD) image sensor having a good signal / noise ratio and a large number of pixels so that the intensity of reflected light from the object 20 can be detected with high accuracy in units of pixels. . In addition to the CCD, a MOS image sensor, a Cd-Se contact image sensor, an aSi contact image sensor, a bipolar contact image sensor, or the like may be used as the solid-state imaging device.
[0047]
The control unit 60 controls the light emission timing at which the irradiation unit 40 emits light and the imaging timing at which the imaging unit 70 images reflected light. The control unit 40 receives the synchronization signal and controls the light emission timing and the imaging timing based on the synchronization signal. Further, the control unit 60 may control the intensity of light emitted by the irradiation unit 40, the focus of the imaging unit 70, the diaphragm, and the like based on the distance information to the object 20. The control unit 60 may control the exposure time of the imaging unit 70.
[0048]
In this example, the irradiation unit 40 irradiates light having one wavelength as a main wavelength component at each of the two irradiation positions, but in another example, the irradiation unit 40 has two irradiation positions. Thus, light having a plurality of wavelengths as main wavelength components may be irradiated. At this time, the spectroscopic unit 50 preferably divides the reflected light from the object 20 into wavelength components of a plurality of wavelengths of the light irradiated by the irradiation unit 40. However, when dividing into all wavelength components, the spectroscopic unit 50 may become too large. Therefore, in yet another example, the irradiation unit 40 has a wavelength λ at the irradiation position 12. _a Is irradiated with light having a main wavelength component, and at the irradiation position 14, two types of wavelengths are used as main wavelength components, and an average value of the two types of wavelengths is a wavelength λ. _a You may irradiate the light which becomes. At this time, the spectroscopic unit 50 divides the light reflected by the object 20 into wavelength components of light emitted from the respective irradiation positions. That is, the spectroscopic unit 50 divides the reflected light into two types of light. The image processing apparatus 300 calculates each piece of information on the object 20 based on the reflected light intensity of the light irradiated from the irradiation position 12 and 1/2 of the reflected light intensity of the light irradiated from the irradiation position 14.
[0049]
In this example, the spectroscopic unit 50 has a prism. However, in another example, the spectroscopic unit 50 may have a plurality of optical filters that mainly transmit light of different wavelengths. The optical filter is disposed on the light receiving surface of the imaging unit 70. Moreover, when the irradiation part 40 does not irradiate light simultaneously in each irradiation position, the imaging part 70 may image reflected light without going through the spectroscopic part 50.
[0050]
FIG. 7 shows an example of the wavelength of light emitted from the irradiation position (12, 14). In this example, light having λa as a main wavelength component is irradiated from the irradiation position 12, and light having two wavelengths λb and λc as main wavelength components is irradiated from the irradiation position 12. The intensity of the reflected light from the object 20 by the light irradiated from the irradiation position 12 is W, and the intensity of the reflected light from the object 20 by the light having the wavelength λb among the light irradiated from the irradiation position 14. Is Wb, and the intensity of light reflected from the object 20 by light having the wavelength λc as a component is Wc. In this case, the spectroscopic unit 50 divides the reflected light from the object 20 into light having a wavelength λa as a main wavelength component and light having wavelengths λa and λb as main wavelength components. The spectroscopic unit 50 may divide the reflected light from the object 20 using, for example, an optical filter.
[0051]
As shown in FIG. 7A, when the light having the average value of the wavelength λb and the wavelength λc is irradiated from the irradiation position 14, the intensity Wb of the reflected light by the light having the wavelength λb as a component, and the wavelength By calculating the average value Wa of the reflected light intensity Wc by the light having λc as a component, the intensity of the reflected light from the object 20 when the light having the wavelength λa is irradiated from the irradiation position 14 can be calculated. . That is, with respect to the reflected light intensity taking into account the attenuation of an optical filter or the like for dividing the reflected light, 1 of the intensity of the reflected light by the light having the wavelengths λb and λc irradiated from the irradiation position 14 as main wavelength components. By calculating / 2, it is possible to calculate the intensity of the reflected light from the object 20 when the light having the wavelength λa is irradiated from the irradiation position 14.
[0052]
Further, as shown in FIG. 7B, by linearly approximating the intensity of the reflected light by the light components having the wavelength λb and the wavelength λc, the object 20 when the light having the wavelength λa is irradiated from the irradiation position 14 is used. The intensity of the reflected light may be calculated. As described in this example, the object 20 is irradiated with light having different wavelengths at the respective irradiation positions, and the reflected light from the object 20 is wavelength-separated by the spectroscopic unit 50 and imaged, so that the two points can be picked up. Since each reflected light by the irradiated light can be imaged simultaneously, even when the object 20 is moving, distance information to the object 20 and surface tilt information can be calculated. In FIG. 7, light having two wavelength components as main wavelength components is irradiated from the irradiation position 14, but in another example, light having more wavelengths as main wavelength components is applied to the object 20. It may be irradiated.
[0053]
FIG. 8 shows an example of the image processing apparatus 300. The image processing apparatus 300 may have the same or similar functions and configurations as the image processing apparatus 300 described with reference to FIG. In this example, the input unit 80, the recording unit 90, and the output unit 120 have the same or similar functions and configurations as those described with reference to FIG.
[0054]
The calculation unit 110 includes a CPU 82, an input device 88, a ROM 84, a hard disk 92, a RAM 86, and a CD-ROM drive 94. The CPU 82 operates based on programs stored in the ROM 84 and the RAM 86. Data is input by the user via an input device 88 such as a keyboard or a mouse. The hard disk 92 stores data such as images and a program for operating the CPU 82. The CD-ROM drive 94 reads data or a program from the CD-ROM 96 and provides it to at least one of the RAM 86, the hard disk 92, and the CPU 82.
[0055]
The functional configuration of the program executed by the CPU 82 is the same as the functional configuration of the calculation unit 110 of the image processing apparatus 300 described with reference to FIG. 4. When the object 20 is irradiated with light from two irradiation positions, An input module for inputting the intensity of reflected light from the object 20 by light from each irradiation position, and a calculation module for calculating distance information to the object 20 based on the intensity of each reflected light. The processing that the input module and calculation module cause the CPU 82 to perform is the same as the function and operation of the calculation unit 110 described with reference to FIG. These programs are provided to the user stored in a recording medium such as the CD-ROM 84. A CD-ROM 96 as an example of a recording medium can store a part or all of the functions of the image processing apparatus 300 described in the present application.
[0056]
The above program may be read directly from the recording medium into the RAM 86 and executed by the CPU 82. Alternatively, the program can use a recording medium to a magnetic recording medium such as a hard disk (MD), a magneto-optical recording medium such as an MO, a tape-shaped recording medium, a nonvolatile semiconductor memory card, or the like.
[0057]
The above program may be stored in a single recording medium or may be divided and stored in a plurality of recording media. The program may be stored after being compressed in a recording medium. The compressed program may be decompressed, read to another recording medium such as the RAM 86, and executed. Furthermore, the compressed program may be decompressed by the CPU 82 and installed in the hard disk 92 or the like, and then read out to another recording medium such as the RAM 86 and executed.
[0058]
Further, the CD-ROM 96 as an example of the recording medium may store the above-described program provided by the host computer via a communication network. The above program stored in the recording medium may be stored in the hard disk of the host computer, transmitted from the host computer to the computer via the communication network, read out to another recording medium such as the RAM 86, and executed. .
[0059]
The recording medium storing the above-described program is used only for manufacturing the image processing apparatus 300 of the present application, and the manufacture and sale of such a recording medium as a row is a patent certificate based on the present application. It is clear that it constitutes an infringement.
[0060]
FIG. 9 shows an example of a flowchart of the information acquisition method according to the present invention. The information acquisition method according to the present invention images an irradiation stage of irradiating an object with light from two optically different irradiation positions and reflected light from the object by light irradiated from the two irradiation positions. An imaging stage, an angle calculation stage for calculating one of the angles at which the object is irradiated with light from two optically different irradiation positions, reflected light of the measured part of the object captured at the imaging position, and And a calculation step of calculating distance information to the measured portion based on reflected light from the vicinity of the measured portion. In this example, in the imaging stage, the reflected light from the object by the light emitted from the two irradiation positions is respectively imaged at the imaging position that is optically the same as one of the two irradiation positions, and the angle In the measurement stage, an angle for irradiating light is calculated based on the reflected light from the object imaged in the imaging stage.
[0061]
The calculation stage is based on the intensity of the reflected light from the part to be measured and the intensity of the reflected light from the vicinity of the part to be measured, and the surface inclination information of the part to be measured, captured in the imaging stage. May be calculated. Hereinafter, a method for calculating the distance information to the part to be measured in the calculation stage will be described using a flowchart.
[0062]
In the calculation step, first, in the first calculation step, provisional distance information to the measured portion is assumed based on the intensity of the reflected light from the measured portion and the incident angle of the reflected light (S100). Next, based on the assumed distance information, the surface tilt information of the part to be measured is calculated (S102). The method of calculating the surface tilt information of the measurement target based on the assumed distance information may be calculated by the same or similar method as the method described in relation to FIGS.
[0063]
Next, in the second calculation stage, temporary distance information in the vicinity of the measured part is calculated based on the temporary distance information to the measured part and the surface tilt information of the measured part (S104). The method for calculating the temporary distance information in the vicinity of the part to be measured may be calculated by the same or similar method as the method described in relation to FIGS.
[0064]
Next, in the third calculation stage, based on the temporary distance information in the vicinity of the measured part, the intensity of the reflected light from the vicinity of the measured part, and the incident angle of the reflected light, the surface inclination in the vicinity of the measured part Information is calculated (S106). The method of calculating the surface tilt information in the vicinity of the part to be measured may be calculated by the same or similar method as the method described with reference to FIGS.
[0065]
Next, in a fourth calculation step, an error between the surface tilt information of the part to be measured and the surface tilt information near the part to be measured is calculated (S108). It is determined whether or not the calculated error is within a predetermined range (S110), and when the calculated error is within the predetermined range, the temporary distance information of the measured part is obtained as the true distance of the measured part. It outputs as distance information (S112). When the calculated error is outside the predetermined range, the temporary distance information of the measured part is set as another value and the process returns to the first calculation stage. That is, the calculation from S100 to S110 is performed for a plurality of temporary distance information of the measured part, and the fourth calculation stage calculates an error for each of the plurality of temporary distance information of the measured part. In the calculation step, the provisional distance information of the measured part when the error is minimized may be the true distance information of the measured part. Based on the calculated distance information, it is possible to calculate the surface tilt information of the measured part.
[0066]
Similar to the method described with reference to FIG. 2, the second calculation step is based on the surface inclination information of the part to be measured, and in the vicinity where the surface of the part to be measured is extended, a temporary distance near the part to be measured. Information may be calculated. In the imaging stage, reflected light from the part to be measured and reflected light from a plurality of places near the part to be measured are imaged. In the fourth calculation stage, the light to be measured is taken at a plurality of places near the part to be measured. Calculate the error between the provisional surface tilt information of the measurement unit and the provisional surface tilt information in the vicinity of the measurement unit, and the calculation step is the provisional distance information of the measurement unit when the sum of squares of the error is minimized. May be the distance information of the true part to be measured. By performing the calculation described in the flowchart based on image data obtained from reflected light from a plurality of locations in the vicinity of the part to be measured, distance information to the part to be measured with reduced noise and calculation error can be obtained. it can.
[0067]
The irradiation stage irradiates light of different wavelengths to the measured part of the object and the vicinity of the measured part at each irradiation position, and irradiates the object substantially simultaneously at each irradiation position. Further, wavelength selection means for selectively transmitting each of light having different wavelengths may be provided, and reflected light from an object by light at each irradiation position may be respectively imaged.
[0068]
In the information acquisition method described with reference to FIG. 8, the distance information and the surface inclination information to the measurement target may be calculated in the same or similar manner as the method described with reference to FIGS. .
[0069]
As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above embodiment. It is apparent from the description of the scope of claims that embodiments with such changes or improvements can be included in the technical scope of the present invention.
[0070]
【The invention's effect】
As is clear from the above description, according to the present invention, the distance information to the object is obtained by imaging the reflected light obtained from the object irradiated with light, eliminating the error due to the inclination of the surface of the object. It becomes possible. Further, it is possible to acquire the tilt information of the surface of the object 20 and the reflectance information of the surface of the object 20.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating the principle of the present invention.
FIG. 2 shows the distance L to the part to be measured 22 and the surface inclination θ of the part to be measured 22 ₀ It is explanatory drawing of an example of the method of calculating.
FIG. 3 shows a surface inclination θ at a predetermined distance interval within a predetermined range with respect to a temporary distance La. ₀ And surface tilt θ ₀ An example of the result of calculating 'is shown.
FIG. 4 shows an example of the configuration of an image capturing apparatus 100 according to the present invention.
5 shows an example of image data 150 based on reflected light from an object 20 imaged by an imaging unit 70. FIG.
FIG. 6 is a diagram illustrating an example of an image capturing apparatus.
FIG. 7 shows an example of the wavelength of light emitted from the irradiation position (12, 14).
8 shows an example of an image processing apparatus 300. FIG.
FIG. 9 shows an example of a flowchart of an information acquisition method according to the present invention.
[Explanation of symbols]
10 ... Camera, 12, 14 ... Irradiation position
20 ... object, 22 ... measured part
24: Near the part to be measured, 40 ... Irradiation part
50 ... spectral part, 52 ... optical lens
60 ... control unit, 70 ... imaging unit
80 ... Input unit, 82 ... CPU
84 ... ROM, 86 ... RAM
88 ... Input device, 92 ... Hard disk
94 ... CD-ROM drive, 96 ... CD-ROM
90... Storage unit, 100.
110 ... calculation unit, 120 ... output unit
150: image data, 300: image processing apparatus

Claims (34)

An information acquisition method for acquiring distance information to an object and surface tilt information of the object,
An angle calculating step for calculating one of the angles at which the object is irradiated with light from two optically different irradiation positions;
Based on the reflected light from the measured part of the object by the light emitted from the two irradiation positions and the reflected light from the vicinity of the measured part, the distance information to the measured part and the measured target A calculation stage for calculating surface tilt information of the measurement unit;
With
The calculating step includes
Based on the intensity of the reflected light from the measured part and the angle of irradiating the object with the light calculated by the angle calculating step, assuming temporary distance information to the measured part, the measured A first calculation stage for calculating surface inclination information of the part;
A second calculation step of calculating temporary distance information in the vicinity of the measured part based on the temporary distance information to the measured part and the surface inclination information of the measured part;
Based on the temporary distance information in the vicinity of the measurement target, the intensity of reflected light from the vicinity of the measurement target, and the angle at which the object is irradiated with light calculated by the angle calculation step, A third calculation stage for calculating surface tilt information in the vicinity of the measurement unit;
A fourth calculation step of calculating an error between the surface inclination information of the measured part and the surface inclination information near the measured part;
An information acquisition method for outputting the temporary distance information of the measured part as the true distance information of the measured part when the error is within a predetermined range. The fourth calculating step calculates the error for each of a plurality of temporary distance information of the measured part,
The information acquisition method according to claim 1, wherein, in the calculation step, provisional distance information of the measured part when the error is minimum is used as true distance information of the measured part. 2. The second calculation step calculates the temporary distance information in the vicinity of the measured part in the vicinity of an extended surface of the measured part based on the surface inclination information of the measured part. The information acquisition method according to claim 2. The calculation step extracts the intensity of reflected light of each light emitted from the two irradiation positions for each pixel, and extracts the measured light from the vicinity of the measured part and the measured part. The information acquisition method according to claim 1, wherein the distance information distribution and the surface tilt information distribution of the object are calculated based on the intensity of the reflected light for each pixel. The information acquisition method according to claim 4, wherein the calculating step calculates three-dimensional information of the object based on a distribution of the distance information and a distribution of the surface inclination information. In the fourth calculation step, at a plurality of locations in the vicinity of the part to be measured, an error between the provisional surface inclination information of the part to be measured and the provisional surface inclination information in the vicinity of the part to be measured is calculated,
6. The calculation step according to claim 1, wherein the provisional distance information of the measured part when the sum of squares of the error is minimized is the true distance information of the measured part. Information acquisition method. The calculating step detects an edge of the object based on image data of the object,
In the calculation step, an area in which the data of the measured part is present is an area obtained by dividing the image data of the object into a plurality of areas from a plurality of locations in the vicinity of the measured part as boundaries. The provisional surface tilt information at a location in the vicinity of the part to be measured, where the data is in the same area as The information acquisition method according to claim 6, wherein the distance information of the measured part is calculated based on the information. In the calculating step, the difference between the intensity of reflected light from the measured part and the intensity of reflected light from the vicinity of the measured part is within a predetermined range among a plurality of locations in the vicinity of the measured part. The information acquisition method according to claim 7, wherein the distance information of the measured part is calculated based on the temporary surface inclination information of a location in the vicinity of the measured part. An irradiation stage for irradiating the object with light from two optically different irradiation positions;
An imaging stage for imaging reflected light from the object by the light emitted from the two irradiation positions;
Further comprising
The calculating step includes
Based on the reflected light from the measured part of the object and the reflected light from the vicinity of the measured part captured by the imaging step, the distance information to the measured part and the surface inclination of the measured part The information acquisition method according to claim 1, wherein the information is calculated. In the imaging step, at the imaging position that is optically the same as one of the two irradiation positions, the reflected light from the object by the light irradiated from the two irradiation positions is respectively imaged.
The information acquisition method according to claim 9, wherein the angle calculation step calculates an angle at which the light is irradiated based on reflected light from the object imaged by the imaging step. 11. The control method according to claim 9, further comprising: a control step of synchronizing an emission timing at which the irradiation step irradiates the light and an imaging timing at which the imaging step images the reflected light at each of the irradiation positions. Information acquisition method. The irradiating step irradiates the light of different wavelengths at each of the irradiation positions, and irradiates the object substantially simultaneously at the respective irradiation positions;
Further comprising a spectroscopic step of separating the reflected light of the different wavelength light from the object into light having each of the different wavelengths as main wavelength components,
The information acquisition method according to claim 11, wherein the imaging step images each of the separated lights. The information acquisition method according to claim 12, wherein the spectroscopic step uses a plurality of optical filters that mainly transmit each of the light beams having different wavelengths. An image capturing apparatus that acquires distance information to an object and surface tilt information of the object,
An angle calculation unit for calculating one of the angles at which the object is irradiated with light from two optically different irradiation positions;
Based on the reflected light from the measured part of the object by the light emitted from the two irradiation positions and the reflected light from the vicinity of the measured part, the distance information to the measured part and the measured target A calculation unit for calculating surface tilt information of the measurement unit;
With
The calculation unit includes:
Based on the intensity of reflected light from the measured part and the angle of irradiating the object with light calculated by the angle calculating part, assuming temporary distance information to the measured part, the measured First calculating means for calculating surface tilt information of the part;
Second calculation means for calculating temporary distance information in the vicinity of the measured part based on the temporary distance information to the measured part and the surface inclination information of the measured part;
The provisional distance information in the vicinity of the part to be measured and the intensity of reflected light from the vicinity of the part to be measured; And third calculation means for calculating surface tilt information in the vicinity of the measured part based on the angle of irradiating the object with light calculated by the angle calculating part;
Fourth calculation means for calculating an error between the surface inclination information of the measured part and the surface inclination information near the measured part;
An image pickup apparatus that outputs the temporary distance information of the measured part as the true distance information of the measured part when the error is within a predetermined range. The fourth calculation means calculates the error for each of a plurality of temporary distance information of the measured part,
The image capturing apparatus according to claim 14, wherein the calculation unit sets the temporary distance information of the measured unit when the error is minimum as the true distance information of the measured unit. The said 2nd calculation means calculates the said temporary distance information of the vicinity of the said to-be-measured part in the vicinity which extended the surface of the to-be-measured part based on the surface inclination information of the to-be-measured part. The image capturing device according to claim 15. The calculation unit extracts the intensity of reflected light of each light emitted from the two irradiation positions for each pixel, and extracts the measured light from the vicinity of the measured part and the measured part. The image imaging device according to claim 14, wherein the distance information distribution and the surface tilt information distribution of the object are calculated based on the intensity of the reflected light for each pixel. The image capturing apparatus according to claim 17, wherein the calculation unit calculates three-dimensional information of the object based on a distribution of the distance information and a distribution of the surface inclination information. The fourth calculating means calculates an error between the provisional surface inclination information of the measured part and the provisional surface inclination information near the measured part at a plurality of locations in the vicinity of the measured part,
19. The calculation unit according to claim 14, wherein the provisional distance information of the measured unit when the sum of squares of the error is minimum is the true distance information of the measured unit. Imaging device. The calculation unit detects an edge of the object based on image data of the object,
The calculation unit is an area in which the data of the measured part is present in an area obtained by dividing the image data of the object into a plurality of areas with the edge of the object as a boundary among a plurality of places in the vicinity of the measured part The image capturing apparatus according to claim 19, wherein the distance information of the measured part is calculated based on the temporary surface inclination information of a place near the measured part where the data is in the same area. The calculation unit includes a plurality of locations in the vicinity of the part to be measured, and a difference between the intensity of reflected light from the part to be measured and the intensity of reflected light from the vicinity of the part to be measured is within a predetermined range. 21. The image capturing apparatus according to claim 20, wherein distance information of the measurement target part is calculated based on the temporary surface inclination information of a location in the vicinity of the measurement target part. An irradiation unit for irradiating the object with light from two optically different irradiation positions;
An imaging unit that images reflected light from the object by the light emitted from the two irradiation positions;
Further comprising
The calculation unit includes:
Based on the reflected light from the measured part of the object and the reflected light from the vicinity of the measured part captured by the imaging unit, the distance information to the measured part and the surface inclination of the measured part The image capturing apparatus according to any one of claims 14 to 21, which calculates information. The imaging unit images reflected light from the object by the light emitted from the two irradiation positions at an imaging position that is optically the same as one of the two irradiation positions, respectively.
The image imaging apparatus according to claim 22, wherein the angle calculation unit calculates an angle at which the light is irradiated based on reflected light from the object imaged by the imaging unit. 24. The control unit according to claim 22, further comprising: a control unit that synchronizes a light emission timing at which the irradiation unit irradiates the light and an imaging timing at which the imaging unit images the reflected light at each of the irradiation positions. Imaging device. The irradiation unit irradiates the light of different wavelengths at each of the irradiation positions, and irradiates the light to the object substantially simultaneously at the respective irradiation positions;
A spectroscopic unit that separates the reflected light from the object of light of different wavelengths into light having each of the different wavelengths as main wavelength components;
The image capturing device according to claim 24, wherein the image capturing unit captures each of the separated lights. The image capturing apparatus according to claim 25, wherein the spectroscopic unit uses a plurality of optical filters that mainly transmit each of the light beams having different wavelengths. An image processing apparatus for acquiring distance information to an object and surface tilt information of the object,
An angle calculation unit for calculating one of the angles at which the object is irradiated with light from two optically different irradiation positions;
Based on the reflected light from the measured part of the object by the light emitted from the two irradiation positions and the reflected light from the vicinity of the measured part, the distance information to the measured part and the measured target A calculation unit for calculating surface tilt information of the measurement unit;
With
The calculation unit includes:
Based on the intensity of reflected light from the measured part and the angle of irradiating the object with light calculated by the angle calculating part, assuming temporary distance information to the measured part, the measured First calculating means for calculating surface tilt information of the part;
Second calculation means for calculating temporary distance information in the vicinity of the measured part based on the temporary distance information to the measured part and the surface inclination information of the measured part;
Based on the temporary distance information in the vicinity of the measurement target, the intensity of reflected light from the vicinity of the measurement target, and the angle at which the object is irradiated with light calculated by the angle calculation unit. Third calculation means for calculating surface tilt information in the vicinity of the measurement unit;
Fourth calculation means for calculating an error between the surface inclination information of the measured part and the surface inclination information near the measured part;
An image processing apparatus that outputs the temporary distance information of the measured part as the true distance information of the measured part when the error is within a predetermined range. The fourth calculation means calculates the error for each of a plurality of temporary distance information of the measured part,
28. The image processing apparatus according to claim 27, wherein the calculation unit sets the temporary distance information of the measured unit when the error is minimum as the true distance information of the measured unit. The said 2nd calculation means calculates the temporary distance information of the vicinity of the said to-be-measured part in the vicinity which extended the surface of the to-be-measured part based on the surface inclination information of the to-be-measured part. The image processing apparatus according to claim 28. The calculation unit extracts the intensity of reflected light of each light emitted from the two irradiation positions for each pixel, and extracts the measured light from the vicinity of the measured part and the measured part. 30. The image processing apparatus according to claim 27, wherein the distance information distribution and the surface inclination information distribution of the object are calculated based on the intensity of the reflected light for each pixel. The image processing device according to claim 30, wherein the calculation unit calculates three-dimensional information of the object based on the distribution of the distance information and the distribution of the surface inclination information. The fourth calculating means calculates an error between the provisional surface inclination information of the measured part and the provisional surface inclination information near the measured part at a plurality of locations in the vicinity of the measured part,
The calculation unit according to any one of claims 27 to 31, wherein the provisional distance information of the measured part when the sum of squares of the error is minimized is the true distance information of the measured part. Image processing device. The calculation unit detects an edge of the object based on image data of the object,
The calculation unit is an area in which the data of the measured part is present in an area obtained by dividing the image data of the object into a plurality of areas with the edge of the object as a boundary among a plurality of places in the vicinity of the measured part 33. The image processing apparatus according to claim 32, wherein distance information of the measured part is calculated based on the provisional surface inclination information of a location in the vicinity of the measured part where the data is in the same area. The calculation unit includes a plurality of locations in the vicinity of the part to be measured, and a difference between the intensity of reflected light from the part to be measured and the intensity of reflected light from the vicinity of the part to be measured is within a predetermined range. 34. The image processing apparatus according to claim 33, wherein distance information of the measured part is calculated based on the provisional surface inclination information of a location in the vicinity of the measured part.

Images