JP3664004B2

JP3664004B2 - Coating film detection method

Info

Publication number: JP3664004B2
Application number: JP33507399A
Authority: JP
Inventors: ▲祐▼治佐久間; 新治畑澤; 和男澤田
Original assignee: Matsushita Electric Works Ltd
Current assignee: Panasonic Electric Works Co Ltd
Priority date: 1999-11-25
Filing date: 1999-11-25
Publication date: 2005-06-22
Anticipated expiration: 2019-11-25
Also published as: JP2001153803A

Description

【０００１】
【発明の属する技術分野】
本発明は、塗膜検出方法に関し、詳しくは紫外線保護材として塗布する蛍光性を持った紫外線吸収塗料の膜圧を検出する方法に関するものである。
【０００２】
【従来の技術】
従来一般に、プールの周壁面とか、屋上の床や壁などに、紫外線吸収剤を塗布しているが、紫外線は肉眼では見えないため、実際に紫外線吸収剤が機能しているか否かを判断するのは困難であった。殊に紫外線吸収剤がクリア塗料である場合にあっては、目視や画像処理を単独で用いた方法では、クリア塗料の有無の判定すら困難であり、さらに塗料の厚みの検査は困難であった。
【０００３】
そこで、特開平１０−２７８８４７８号公報には、クリア塗料などの透明塗装を検出する方法として、紫外線等の特定波長の照明光を用い、塗装部は透明塗装の正反射成分が強くなること、逆に未塗装部は乱反射するため正反射部分が弱くなることを利用して、透明塗装の有無を検出する方法が開示されている。
【０００４】
【発明が解決しようとする課題】
しかしながら、従来のように光反射を利用した透明塗装の検出方法にあっては、未塗装部が粗い面で光沢がないことが前提条件となり、そのために滑らかな光沢のある材質の場合には効果がないものである。つまり、塗装の有無の判別はある程度できても、塗膜の厚みは正確に測定できないという欠点があった。
【０００５】
本発明は、上記の従来例の問題点に鑑みて発明したものであって、その目的とするところは、塗膜の有無の判別及び塗膜の厚みを高速で且つ高精度で測定することができる塗膜検出方法を提供するにある。
【０００６】
【課題を解決するための手段】
上記課題を解決するために本発明にあっては、紫外線を吸収すると共に蛍光性を有する塗料を対象物１の表面に塗布して塗膜２を形成し、紫外線を含む照明光を対象物１に照射しながら、複数の特性の異なる撮像装置で撮像し、得られた複数の画像データに基づいて塗膜２の厚みを検出することを特徴としており、このような方法を採用することで、画像処理による塗料の塗布領域４の有無の判別を高い精度で行うことができるうえに、塗布領域４のみを限定して明るさを測定することで、高速での処理が可能となる。
【０００７】
【発明の実施の形態】
以下、本発明を添付図面に示す実施形態に基づいて説明する。
【０００８】
本実施形態では、壁パネル等のような対象物１の表面に、紫外線を吸収すると共に蛍光性を有する塗料が塗布されている。この対象物１の表面に形成された被検査対象となる塗膜２の厚みを検出するにあたって、図１に示すように、紫外線を含む照明光を照射する照明装置１１と、特性の異なる２種類の撮像装置とが用いられる。ここでは同一のカメラ１２を２台設置し、片方のカメラ１２の前に紫外線透過フィルター１０を設置し、他方のカメラ１２の前に可視光透過フィルター９を設置してある。
【０００９】
先ず、図１に示すように、照明装置１１から紫外線を含む照明光を被検査対象である塗膜２に当てながら、２台のカメラ１２で対象物１の表面をそれぞれ撮像する。紫外線透過フィルター１０を通して撮像された紫外線画像データ２１を図２（ａ）に示し、可視光透過フィルター９を通して撮像された可視光画像データ２２を図２（ｂ）に示す。紫外線画像データ２１の下側の暗い領域が塗布領域４であり、この塗布領域４を抽出する。次に、可視光画像データ２２において上記塗布領域４と対応する領域における明るさを測定し、これから塗料の塗布量を推定する。本例では図２（ｂ）の右側にいく程明るさが明るくなり、塗膜２の厚みが厚くなっていると推定する。また図２（ｂ）の左側にいく程暗くなり、塗膜２の厚みが薄くなっていると推定する。
【００１０】
しかして、特性の異なる２種類の透過フィルター（紫外線透過フィルター１０、可視光透過フィルター９）を通して紫外線画像データ２１及び可視光画像データ２２を取得することによって、塗料の塗布領域４の有無の判別を高精度で行うことができるうえに、塗布領域４のみを限定して明るさを測定することによって、高速での処理が可能となり、塗膜２の厚みの測定を高精度且つ高速で行うことができる。しかもカメラ１２を２台使用することによって、２種類の画像（紫外線画像データ２１、可視光画像データ２２）を同一時間に撮像できるため、より高速に処理することが可能となる。
【００１１】
図３は、対象物１に塗料が塗布されない非塗布領域６を予め設けておき、可視光カメラ８による画像データ２３において塗布領域４の明るさを非塗布領域６の明るさで減算して補正することによって、塗膜２での蛍光量のみを求め、これから塗布量を推定する場合の一例を示している。なお、塗布領域４の検出は図１の実施形態と同様、紫外線画像により検出するものとする。図３中の２２は塗布装置を示し、矢印は対象物１の移動方向を示している。先ず、可視光カメラ８の位置を、対象物１である塗料が塗装される前後でそれぞれ撮像可能な位置に設置し、塗布領域４と非塗布領域６の双方を含むように撮像する。さらに本例では、図４に示すように、可視光カメラ８の画像データ２３の左半分が非塗布領域、右半分が塗布領域となるように可視光カメラ８を設置する。得られた画像データ２３の塗布領域の明るさＡ_Ｌと非塗布領域の明るさＡ_Ｒとの差（Ａ_Ｒ−Ａ_Ｌ）から塗膜２での蛍光量を測定し、蛍光の明るさを求め、この明るさから塗料の塗布量を推定する。しかして、対象物１に予め非塗布領域６を設けておき、画像データ２３の塗布領域の明るさＡ_Ｌを非塗布領域の明るさＡ_Ｒで減算して補正することによって、対象物１の色の違いによる影響を軽減でき、従って、より高精度に塗料の塗布量を推定することができるものである。
【００１２】
また、上記図３において、塗料を塗布する前と塗布した後の２つの画像データの変化具合から塗布量を推定することも可能である。例えば図３に示す対象物１の左半分の領域（塗布前）がカメラ視野の左半分に入ったときに第１回目の撮像を行い、その後、上記対象物１の左半分の領域（塗布後）がカメラ視野の右半分に入ったときに第２回目の撮像を行うように、可視光カメラ８の視野、対象物１の移動速度、及び撮像時間間隔を調整してある。図５（ａ）は第１の画像データ２１であり、左半分が対象物１の左半分の領域（塗布前）の明るさＡ_Ｌ１を示している。図５（ｂ）は第２の画像データ２２であり、右半分が対象物１の左半分の領域（塗布後）の明るさＡ_Ｒ２を示している。これら第２の画像データ２２の右半分の領域（塗布後）の明るさＡ_Ｒ２と第１の画像データ２１の左半分の領域（塗布前）の明るさＡ_Ｌ１との差（Ａ_Ｒ２−Ａ_Ｌ１）から蛍光の明るさを求めることによって、塗布量を推定することができる。このように、塗料を塗布する前と塗布した後の２つの画像データ２１，２２の変化具合から塗布量を推定することによって、対象物１の色の違いによる影響を軽減することができ、より高精度に塗料の塗布量が推定可能となる。
【００１３】
ところで、可視光カメラ８により撮像される蛍光量は、塗料を塗布する前の対象物１の色の影響を受けやすい。そこで、可視光を照射して撮像する第１のカメラと、紫外光を照射して撮像する第２のカメラを用いて塗布量を推定することも可能である。ここでは、可視光を照射して撮像する第１のカメラとしてカラーカメラを用い、このカラーカメラにより撮像された画像から色差が概一定となる領域を抽出する。図６（ａ）はカラーカメラで得られた第１の画像データ２１を示し、図６（ｂ）は第２のカメラで得られた第２の画像データ２２を示している。先ず、第１の画像データ２１を色の差により３つの領域Ｂ_１，Ｂ_２，Ｂ_３に分割し、各領域ごとの色を抽出する。次に、その領域ごとに第２の画像データ２２により得られた各領域Ｂ_１ａ，Ｂ_２ａ，Ｂ_３ａの光量を第１の画像データ２１で抽出された色でそれぞれ補正して塗布量を推定する。つまり、第１の画像データ２１における領域Ｂ_１，Ｂ_２，Ｂ_３ごとの色と第２の画像データ２２における各領域Ｂ_１ａ，Ｂ_２ａ，Ｂ_３ａごとの明るさの度合いとから塗料の塗布量を推定することができ、これにより、対象物１の色の違いによる誤差を低減でき、より高精度に塗布量の測定が可能となる。
【００１４】
また上記図６の実施形態において、塗料から発する蛍光の波長を予め調べておき、その波長のみを透過するバンドパスフィルターを第２の画像データ２２を撮像するための第２のカメラの前に設置し、蛍光成分のみを抽出して、蛍光量のみから第２の画像データ２２において明るさの度合いを測定するようにしてもよい。この場合、蛍光成分のみを抽出するために、明るさの測定をより高精度で行うことが可能となる。
【００１５】
図７〜図１０は撮像装置等の他の実施形態を示している。図７は、１台のカメラ１２の前に、少なくとも２種類（例えば紫外線透過フィルター部１０、可視光透過フィルター部９）の波長特性を有する透過フィルター３を設置し、透過フィルター３を回転させて紫外線透過フィルター部１０と可視光透過フィルター部９とに切り替えて撮像する場合を示している。これにより、カメラ１２が１台で済み、構成がシンプルとなり、塗膜２の検出を簡易に行うことができる。なお透過フィルター３の波長特性は３種類以上であってもよい。
【００１６】
図８は、紫外領域と赤外領域の２つの波長特性を有する照明装置１１ａ，１１ｂを組み合わせたり、或いは切り替えたりして、１台のカメラ１２で各々の照明条件における撮像を行うようにしてもよい。これにより、カメラ１２が１台で済み、構成がシンプルになると共に、対象物１の表面の光沢等を同時に検出することが可能となり、検出精度を高めることができる。なお照明装置１１ａ，１１ｂの波長特性は２種類に限定されるものではない。
【００１７】
図９は、１台の照明装置１１と対象物１との間に、少なくとも２種類の波長特性（例えば紫外線透過フィルター部１０、可視光透過フィルター部９）を有する透過フィルター３を設置し、透過フィルター３を回転させて紫外線透過フィルター部１０と可視光透過フィルター部９とに切り替えて撮像する場合を示している。これにより、カメラ１２及び照明装置１１が各々１台で済み、構成が一層シンプルとなる。なお透過フィルター３の波長特性は３種類以上であってもよい。
【００１８】
図１０は、可視光カメラ８と紫外線カメラ７とを別のステージにおいて行う場合を示している。ここでは対象物１がコンベア３０等の移動機構上を移動するような条件で、可視光撮像と紫外線撮像とを別々のステージで行うことによって、実工程上でタクトを落とさずに撮像が可能となり、処理の高速化を図ることができるものである。
【００１９】
【発明の効果】
上述のように本発明にあっては、紫外線を吸収すると共に蛍光性を有する塗料を対象物の表面に塗布して塗膜を形成し、紫外線を含む照明光を対象物に照射しながら、複数の特性の異なる撮像装置で撮像し、得られた複数の画像データに基づいて塗膜の厚みを検出するので、特性の異なる２種類の撮像装置を用いることによって、画像処理による塗料の塗布領域の有無の判別を高い精度で行うことができるうえに、塗布領域のみを限定して明るさを測定することによって、塗膜の厚みを高速で且つ高精度で測定することが可能となる。
【００２０】
また請求項１記載の発明は、上記特性の異なる撮像装置として、紫外線カメラと可視光及び赤外線領域カメラとを用い、紫外線カメラで撮像した紫外線画像において塗料の塗布領域を検出し、可視光及び赤外線領域カメラで得られた可視光及び赤外線画像における上記塗布領域と対応する領域の明るさから塗料の塗布量を推定するので、２台のカメラを用いて、２種類の画像（紫外線画像、可視光画像）を同一時間に撮像できるため、より高速に処理することが可能となる。
【００２１】
また請求項２記載の発明は、請求項１記載の効果に加えて、紫外線画像において塗料の塗布領域を検出し、可視光及び赤外線画像において塗布領域における明るさと塗料が塗布されない非塗布領域における明るさとの差から塗膜での蛍光量を求めて塗布量を推定するので、つまり、画像データの塗布領域の明るさを非塗布領域の明るさで減算して補正することによって明るさの度合いが明確となり、対象物の色の違いによる影響を軽減して、塗布量をより高精度で測定できるようになる。
【００２２】
また請求項３記載の発明は、請求項２記載の効果に加えて、対象物に予め非塗布領域を設けておくようにしたので、非塗布領域での明るさの度合いを容易に検出でき、測定精度が一層向上する。
【００２３】
また請求項４記載の発明は、請求項１記載の効果に加えて、塗料を塗布する前と塗布した後の２つの画像データの変化具合から塗布量を推定するので、対象物の色の違いによる影響を軽減して、より高精度に塗料の塗布量が推定可能となる。
【００２４】
また請求項５記載の発明は、上記特性の異なる複数の撮像装置として、可視光を照射して撮像する第１のカメラと、紫外光を照射して撮像する第２のカメラとを用い、第１のカメラで撮像した第１の画像データを複数領域に分けて各領域ごとの色を抽出すると共に、第２のカメラで撮像した第２の画像データにおいて明るさの度合いを求め、上記各領域ごとの色と明るさから塗料の塗布量を推定するので、第２の画像データにおいて明るさの度合いを求め、第１の画像データにおける領域ごとの色と明るさから塗料の塗布量を推定することによって、対象物の色の違いによる誤差を低減でき、より高精度に塗布量の測定が可能となる。
【００２５】
また請求項６記載の発明は、請求項５記載の効果に加えて、第２の画像データにおいて蛍光物質の蛍光波長成分のみを抽出して明るさの度合いを測定するので、塗料から発する蛍光の波長成分のみを抽出することで、明るさの測定をより高精度で行うことが可能となる。
【００２６】
また請求項７記載の発明は、上記特性の異なる撮像装置として、紫外線透過フィルターとカメラとを組み合わせたものと、可視光透過フィルターとカメラとを組み合わせたものとを用いたので、２台のカメラを使用することによって、２種類の画像（紫外線画像、可視光画像）を同一時間に撮像できるため、より高速に処理することが可能となる。
【００２７】
また請求項８記載の発明は、１台のカメラの前に、少なくとも紫外線透過特性と可視光透過特性の２種類の波長特性を持つ透過フィルターを備え、透過フィルターを切り替えて撮像するので、カメラが１台で済み、構成がシンプルとなり、塗膜の検出を簡易に行うことができる。
【００２８】
また請求項９記載の発明は、紫外線を吸収すると共に蛍光性を有する塗料を対象物の表面に塗布して塗膜を形成し、紫外線を含む照明光を対象物に照射しながら、紫外領域と赤外領域の２つの波長特性を有する照明装置を組み合わせたり、或いは切り替えたりして、１台のカメラで各々の照明条件における撮像を行い、得られた複数の画像データに基づいて塗膜の厚みを検出するので、カメラが１台で済み、構成がシンプルとなり、塗膜の検出を簡易に行うことができると共に、対象物の表面の光沢等を同時に検出することが可能となり、検出精度を高めることができる。
【００２９】
また請求項１０記載の発明は、紫外領域から赤外領域まで含む波長特性を有する１台の照明装置と、照明装置と対象物との間に少なくとも２種類の波長特性を有する透過フィルターとを備え、透過フィルターを切り替えて撮像するので、照明装置が１台で済み、構成がシンプルとなる。
【００３０】
また請求項１１記載の発明は、紫外線を吸収すると共に蛍光性を有する塗料を対象物の表面に塗布して塗膜を形成し、紫外線を含む照明光を対象物に照射しながら、可視光カメラによる撮像と紫外線カメラによる撮像とを別のステージで行い、複数の得られた複数の画像データに基づいて塗膜の厚みを検出するので、実工程上でタクトを落とさずに撮像が可能となる。
【図面の簡単な説明】
【図１】本発明の実施形態の一例を示す斜視図である。
【図２】同上の撮像装置で得られた画像データを示し、（ａ）は紫外線画像において検出された塗布領域の模式図、（ｂ）は可視光画像において検出された明るさの模式図である。
【図３】他の実施形態の斜視図である。
【図４】同上の撮像装置で得られた画像データを示し、非塗布領域の明るさと塗布領域の明るさを説明する模式図である。
【図５】（ａ）は同上の撮像装置で撮像した第１の画像データを説明する模式図、（ｂ）は第２の画像データを説明する模式図である。
【図６】更に他の実施形態を示し、（ａ）は第１の画像データにおいて色の差により抽出される領域を示す模式図、（ｂ）は第２の画像データにおいて第１の画像データで分離された各領域ごとに塗布量を推定する模式図である。
【図７】更に他の実施形態を示す斜視図である。
【図８】更に他の実施形態を示す斜視図である。
【図９】更に他の実施形態を示す斜視図である。
【図１０】更に他の実施形態を示す斜視図である。
【符号の説明】
１対象物
２塗膜
４塗布領域
５撮像装置
６非塗布領域
７紫外線カメラ
８可視光カメラ
９可視光透過フィルター
１０紫外線透過フィルター
１１照明装置
１２カメラ
２１，２２画像データ[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for detecting a coating film, and more particularly to a method for detecting the film pressure of a fluorescent UV-absorbing paint applied as an ultraviolet protective material.
[0002]
[Prior art]
Conventionally, UV absorbers are generally applied to the peripheral wall surface of the pool, the floor and walls of the roof, etc., but since UV rays cannot be seen with the naked eye, it is necessary to judge whether the UV absorber is actually functioning. Was difficult. In particular, when the UV absorber is a clear paint, it is difficult to determine the presence or absence of clear paint, and it is difficult to inspect the thickness of the paint by a method using visual or image processing alone. .
[0003]
Therefore, in Japanese Patent Laid-Open No. 10-2788478, as a method for detecting a transparent coating such as a clear coating, illumination light having a specific wavelength such as ultraviolet rays is used, and the coating portion has a strong regular reflection component of the transparent coating. In addition, there is disclosed a method for detecting the presence or absence of transparent coating by utilizing the fact that the regular reflection portion becomes weak because the unpainted portion is irregularly reflected.
[0004]
[Problems to be solved by the invention]
However, in the conventional transparent coating detection method using light reflection, it is a precondition that the unpainted part is rough and has no gloss, so that it is effective in the case of a smooth glossy material. There is no. That is, there is a drawback that the thickness of the coating film cannot be measured accurately even if the presence or absence of coating can be determined to some extent.
[0005]
The present invention was invented in view of the problems of the above-described conventional examples, and the object of the present invention is to determine the presence or absence of a coating film and to measure the thickness of the coating film at high speed and with high accuracy. It is in providing the coating-film detection method which can be performed.
[0006]
[Means for Solving the Problems]
In order to solve the above-described problems, in the present invention, a coating material that absorbs ultraviolet rays and has fluorescence is applied to the surface of the object 1 to form a coating film 2, and illumination light containing ultraviolet rays is applied to the object 1. , While taking a picture with a plurality of imaging devices having different characteristics, and detecting the thickness of the coating film 2 based on a plurality of obtained image data, by adopting such a method, the determination of the presence or absence of the application area 4 of the paint by the image processing on top that can be performed with high accuracy, by measuring the brightness by limiting only the coating region 4, that Do can be processed at high speed.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described based on embodiments shown in the accompanying drawings.
[0008]
In the present embodiment, a paint that absorbs ultraviolet rays and has fluorescence is applied to the surface of the object 1 such as a wall panel. In detecting the thickness of the coating film 2 to be inspected formed on the surface of the object 1, as shown in FIG. 1, the illumination device 11 that irradiates illumination light including ultraviolet rays and two types having different characteristics are used. The imaging device is used. Here, two identical cameras 12 are installed, an ultraviolet transmission filter 10 is installed in front of one camera 12, and a visible light transmission filter 9 is installed in front of the other camera 12.
[0009]
First, as shown in FIG. 1, the surface of the object 1 is imaged by two cameras 12 while illuminating light including ultraviolet rays is applied from the illumination device 11 to the coating film 2 to be inspected. The ultraviolet image data 21 imaged through the ultraviolet light transmission filter 10 is shown in FIG. 2A, and the visible light image data 22 imaged through the visible light transmission filter 9 is shown in FIG. The dark area below the ultraviolet image data 21 is the application area 4, and the application area 4 is extracted. Next, the brightness in the region corresponding to the coating region 4 in the visible light image data 22 is measured, and the coating amount of the paint is estimated from this. In this example, it is estimated that the brightness increases as it goes to the right side of FIG. 2B, and the thickness of the coating film 2 is increased. In addition, it becomes darker as it goes to the left in FIG. 2B, and it is estimated that the thickness of the coating film 2 is reduced.
[0010]
Thus, by acquiring the ultraviolet image data 21 and the visible light image data 22 through two types of transmission filters (ultraviolet transmission filter 10 and visible light transmission filter 9) having different characteristics, the presence / absence of the coating application region 4 is determined. In addition to being able to be performed with high accuracy, it is possible to perform high-speed processing by measuring the brightness only in the application region 4 and to measure the thickness of the coating film 2 with high accuracy and high speed. it can. In addition, by using two cameras 12, two types of images (ultraviolet image data 21 and visible light image data 22) can be captured at the same time, so that higher speed processing is possible.
[0011]
In FIG. 3, a non-application area 6 where the paint is not applied to the object 1 is provided in advance, and the brightness of the application area 4 is subtracted by the brightness of the non-application area 6 in the image data 23 obtained by the visible light camera 8. In this example, only the amount of fluorescence in the coating film 2 is obtained, and the coating amount is estimated from this. In addition, the detection of the application | coating area | region 4 shall be detected with an ultraviolet image similarly to embodiment of FIG. In FIG. 3, 22 indicates a coating apparatus, and an arrow indicates the moving direction of the object 1. First, the position of the visible light camera 8 is set at a position where imaging can be performed before and after the paint as the object 1 is applied, and imaging is performed so as to include both the application region 4 and the non-application region 6. Furthermore, in this example, as shown in FIG. 4, the visible light camera 8 is installed so that the left half of the image data 23 of the visible light camera 8 is a non-application area and the right half is an application area. Fluorescence amount from the difference (A R _-A _L) in the coating film 2 of the brightness A _R of the brightness A _L and the non-application region of the coating region of the obtained image data 23 were measured, the brightness of the fluorescent The amount of paint applied is estimated from this brightness. Thus, it may be provided a non-application area 6 in advance in the object 1, by correcting by subtracting the brightness A _L of the application region of the image data 23 with the brightness A _R of the non-application area, of the object 1 The influence of the difference in color can be reduced, and therefore the coating amount of paint can be estimated with higher accuracy.
[0012]
In FIG. 3, it is also possible to estimate the application amount from the degree of change in the two image data before and after applying the paint. For example, when the left half region (before application) of the object 1 shown in FIG. 3 enters the left half of the camera field of view, the first imaging is performed, and then the left half region of the object 1 (after application) ) Is adjusted so that the visual field of the visible light camera 8, the moving speed of the object 1, and the imaging time interval are adjusted so that the second imaging is performed when entering the right half of the camera visual field. 5 (a) is a first image data 21, the left half shows the brightness A _L1 of the left half of the area of the object 1 (before application). FIG. 5B shows the second image data 22, and the right half shows the brightness AR ₂ of the left half area (after application) of the object 1. The difference (A _R2 −A) between the brightness A _R2 of the right half area (after application) of the second image data 22 and the brightness A _L1 of the left half area (before application) of the first image data 21 _The amount of application can be estimated by obtaining the brightness of the fluorescence from _L1 ). Thus, by estimating the application amount from the degree of change of the two image data 21 and 22 before and after applying the paint, the influence of the color difference of the object 1 can be reduced, and more The coating amount can be estimated with high accuracy.
[0013]
By the way, the amount of fluorescence imaged by the visible light camera 8 is easily affected by the color of the object 1 before the paint is applied. Therefore, it is also possible to estimate the coating amount using a first camera that irradiates and captures visible light and a second camera that irradiates and captures ultraviolet light. Here, a color camera is used as the first camera for imaging by irradiating visible light, and an area where the color difference is substantially constant is extracted from an image captured by the color camera. 6A shows the first image data 21 obtained by the color camera, and FIG. 6B shows the second image data 22 obtained by the second camera. First, the first image data 21 is divided into _three regions B ₁ , B ₂ , and B _{3 based} on the color difference, and the color for each region is extracted. Then, the regions B _{1 a} obtained by the second image data 22 for each the region, B 2 a, applied to correct each light amount of the _B 3 _a color extracted by the first image data 21 Estimate the amount. That is, from the color for each region B ₁ , B ₂ , B ₃ in the first image data 21 and the degree of brightness for each region B ₁ a, B ₂ a, B ₃ a in the second image data 22. The coating amount of the paint can be estimated, whereby an error due to the color difference of the object 1 can be reduced, and the coating amount can be measured with higher accuracy.
[0014]
In the embodiment shown in FIG. 6, the wavelength of the fluorescence emitted from the paint is checked in advance, and a band pass filter that transmits only the wavelength is installed in front of the second camera for capturing the second image data 22. Alternatively, only the fluorescence component may be extracted, and the degree of brightness in the second image data 22 may be measured from only the fluorescence amount. In this case, since only the fluorescent component is extracted, the brightness can be measured with higher accuracy.
[0015]
7 to 10 show other embodiments such as an imaging device. In FIG. 7, a transmission filter 3 having at least two types of wavelength characteristics (for example, an ultraviolet transmission filter unit 10 and a visible light transmission filter unit 9) is installed in front of one camera 12, and the transmission filter 3 is rotated. The case where it switches to the ultraviolet transmissive filter part 10 and the visible light transmissive filter part 9, and it images is shown. Thereby, only one camera 12 is required, the configuration becomes simple, and the coating film 2 can be easily detected. The transmission filter 3 may have three or more wavelength characteristics.
[0016]
In FIG. 8, the illumination devices 11a and 11b having two wavelength characteristics of the ultraviolet region and the infrared region may be combined or switched so that one camera 12 performs imaging under each illumination condition. Good. Thereby, only one camera 12 is required, the configuration is simplified, and the gloss of the surface of the object 1 can be detected at the same time, so that the detection accuracy can be improved. The wavelength characteristics of the lighting devices 11a and 11b are not limited to two types.
[0017]
In FIG. 9, a transmission filter 3 having at least two types of wavelength characteristics (for example, an ultraviolet transmission filter unit 10 and a visible light transmission filter unit 9) is installed between a single illumination device 11 and an object 1 and transmitted. The case where the filter 3 is rotated to switch to the ultraviolet light transmission filter unit 10 and the visible light transmission filter unit 9 is shown. Accordingly, only one camera 12 and one illumination device 11 are required, and the configuration is further simplified. The transmission filter 3 may have three or more wavelength characteristics.
[0018]
FIG. 10 shows a case where the visible light camera 8 and the ultraviolet camera 7 are performed on different stages. Here, by performing visible light imaging and ultraviolet imaging on separate stages under the condition that the object 1 moves on a moving mechanism such as the conveyor 30, it is possible to perform imaging without dropping tact in the actual process. Thus, the processing speed can be increased.
[0019]
【The invention's effect】
As described above, in the present invention , a plurality of coatings are formed by applying a coating material that absorbs ultraviolet rays and has fluorescence to the surface of an object, and irradiates the object with illumination light including ultraviolet rays. Since the thickness of the coating film is detected on the basis of a plurality of obtained image data, by using two types of imaging devices having different characteristics, the paint application region by image processing is detected. The presence / absence can be determined with high accuracy, and the thickness of the coating film can be measured at high speed and with high accuracy by measuring the brightness only in the application region.
[0020]
The invention according to claim 1, as a different imaging device having the above characteristics, using an ultraviolet camera and a visible light and infrared regions camera detects the application area of the paint in the ultraviolet image captured by ultraviolet camera, a visible light and infrared Since the coating amount of the paint is estimated from the brightness of the region corresponding to the coating region in the visible light and infrared image obtained by the region camera, two types of images (ultraviolet image, visible light) are used using two cameras. Image) can be taken at the same time, so that it can be processed at higher speed.
[0021]
In addition to the effect of the first aspect , the invention described in claim 2 detects the application area of the paint in the ultraviolet image, and the brightness in the application area and the brightness in the non-application area where the paint is not applied in the visible light and infrared images. The amount of fluorescence in the coating film is estimated from the difference between the two and the coating amount is estimated.In other words, the brightness level can be adjusted by subtracting the brightness of the coating area of the image data from the brightness of the non-coating area. It becomes clear and the influence of the color difference of the object can be reduced, and the coating amount can be measured with higher accuracy.
[0022]
In addition to the effect described in claim 2 , the invention described in claim 3 is provided with a non-application area in advance in the object, so that the degree of brightness in the non-application area can be easily detected, Measurement accuracy is further improved.
[0023]
In addition to the effect described in claim 1 , the invention described in claim 4 estimates the application amount from the degree of change in the two image data before and after applying the paint. The amount of paint applied can be estimated with higher accuracy.
[0024]
The invention according to claim 5, as a plurality of imaging devices having different characteristics described above, using a first camera that captures by irradiating visible light, and a second camera for imaging by irradiating ultraviolet light, the The first image data picked up by one camera is divided into a plurality of regions and the color of each region is extracted, the degree of brightness is determined in the second image data picked up by the second camera, and each of the above regions Since the coating amount of paint is estimated from the color and brightness of each image, the degree of brightness is obtained from the second image data, and the coating amount of paint is estimated from the color and brightness of each region in the first image data. Thus, an error due to the color difference of the object can be reduced, and the coating amount can be measured with higher accuracy.
[0025]
In addition to the effect described in claim 5 , the invention described in claim 6 extracts only the fluorescence wavelength component of the fluorescent substance from the second image data and measures the brightness level, so that the fluorescence emitted from the paint can be measured. By extracting only the wavelength component, the brightness can be measured with higher accuracy.
[0026]
The invention according to claim 7, as different imaging device having the above characteristics, and a combination of a ultraviolet transmitting filter and the camera, so was used as a combination of a visible light transmission filter and the camera, two cameras By using, two types of images (ultraviolet image and visible light image) can be taken at the same time, so that it is possible to process at higher speed.
[0027]
The invention according to claim 8, in front of one camera, provided with a transmission filter having two kinds of wavelength characteristics of at least ultraviolet transmission characteristic and visible light transmission characteristic, since the imaging by switching the transmission filter, the camera Only one unit is required, the configuration becomes simple, and the coating film can be easily detected.
[0028]
Further, the invention according to claim 9 absorbs ultraviolet rays and coats the surface of the object with a fluorescent paint to form a coating film, and irradiates the object with illumination light including ultraviolet rays, Combine or switch lighting devices having two wavelength characteristics in the infrared region, and perform imaging under each lighting condition with one camera, and the thickness of the coating film based on the obtained multiple image data and detects a camera requires only one, configuration becomes simple, it is possible to detect the coating film simply, it is possible to detect the gloss of the surface of the object at the same time, improve the detection accuracy be able to.
[0029]
The invention according to claim 10 includes: one illuminating device having wavelength characteristics including from the ultraviolet region to the infrared region; and a transmission filter having at least two types of wavelength characteristics between the illuminating device and the object. In addition, since the imaging is performed by switching the transmission filter, only one illumination device is required, and the configuration becomes simple.
[0030]
Further, the invention described in claim 11 is a visible light camera that absorbs ultraviolet rays and applies a fluorescent paint to the surface of the object to form a coating film, and irradiates the object with illumination light including ultraviolet rays. Since the film thickness is detected on the basis of a plurality of obtained image data , imaging can be performed without dropping tact in the actual process. .
[Brief description of the drawings]
FIG. 1 is a perspective view showing an example of an embodiment of the present invention.
FIGS. 2A and 2B show image data obtained by the above imaging apparatus, wherein FIG. 2A is a schematic diagram of a coating area detected in an ultraviolet image, and FIG. 2B is a schematic diagram of brightness detected in a visible light image; is there.
FIG. 3 is a perspective view of another embodiment.
FIG. 4 is a schematic diagram illustrating image data obtained by the imaging apparatus according to the embodiment and explaining brightness of a non-application area and brightness of an application area.
FIG. 5A is a schematic diagram for explaining first image data captured by the same imaging apparatus, and FIG. 5B is a schematic diagram for explaining second image data.
6A and 6B show still another embodiment, in which FIG. 6A is a schematic diagram showing an area extracted by color difference in the first image data, and FIG. 6B is the first image data in the second image data. It is a schematic diagram which estimates the application quantity for every area | region isolate | separated by (1).
FIG. 7 is a perspective view showing still another embodiment.
FIG. 8 is a perspective view showing still another embodiment.
FIG. 9 is a perspective view showing still another embodiment.
FIG. 10 is a perspective view showing still another embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Object 2 Coating film 4 Application | coating area | region 5 Imaging device 6 Non-application | coating area | region 7 Ultraviolet camera 8 Visible light camera 9 Visible light transmission filter 10 Ultraviolet transmission filter 11 Illumination device 12 Camera 21, 22 Image data

Claims

Apply UV paint and fluorescent paint on the surface of the object to form a coating film, and irradiate the object with ultraviolet light including UV light, and use UV camera and visible and infrared region camera captured Te, in the ultraviolet image captured by ultraviolet camera detects the application area of the paint, coating the brightness of the area corresponding to the application region in the resulting visible light and infrared images in the visible and infrared regions cameras paint by estimating the amount of coating film detecting how to and detecting a thickness of the coating film based on a plurality of image data obtained.

Detecting the coating area in the UV image, and estimating the coating quantity by obtaining the amount of fluorescence in the coating film from the difference between the brightness in the coating area and the brightness in the non-coating area where the paint is not applied in the visible and infrared images The method for detecting a coating film according to claim 1 .

The coating film detection method according to claim 2, wherein a non-application area is provided in advance on the object .

2. The method of detecting a coating film according to claim 1, wherein the coating amount is estimated from changes in two image data before and after applying the paint.

A first camera that absorbs ultraviolet rays and forms a coating film by applying a paint having fluorescence on the surface of the object, and irradiates the object with illumination light including ultraviolet rays and irradiates the object with visible light. And a second camera that irradiates and irradiates ultraviolet light, and the first image data captured by the first camera is divided into a plurality of regions to extract colors for each region, and the second By calculating the degree of brightness in the second image data captured by the camera and estimating the coating amount from the color and brightness for each of the above regions, the coating film is obtained based on the obtained plurality of image data. A method for detecting a coating film , comprising detecting a thickness .

6. The method of detecting a coating film according to claim 5, wherein only the fluorescence wavelength component of the fluorescent material is extracted from the second image data and the degree of brightness is measured .

A combination of a UV transmissive filter and a camera, while absorbing ultraviolet rays and applying a fluorescent paint on the surface of the object to form a coating film, irradiating the object with illumination light containing ultraviolet rays, A method for detecting a coating film, comprising: imaging using a combination of a visible light transmission filter and a camera, and detecting a thickness of the coating film based on a plurality of obtained image data .

A paint that absorbs ultraviolet rays and has a fluorescent property is applied to the surface of the object to form a coating film, and has at least two wavelength characteristics of ultraviolet transmission characteristics and visible light transmission characteristics in front of one camera. A coating is provided, wherein the object is irradiated with illumination light including ultraviolet rays, the transmission filter is switched, the image is captured by a camera, and the thickness of the coating film is detected based on a plurality of obtained image data. Membrane detection method.

Applying a fluorescent paint to the surface of the object to absorb ultraviolet rays and forming a coating film, and irradiating the object with illumination light containing ultraviolet rays, the two wavelength characteristics of the ultraviolet region and infrared region The coating apparatus is characterized by combining or switching the illumination devices having, and performing imaging under each illumination condition with a single camera, and detecting the thickness of the coating film based on a plurality of obtained image data. Membrane detection method.

A lighting device that absorbs ultraviolet rays and has a fluorescent property applied to the surface of an object to form a coating film, and has a wavelength characteristic including from the ultraviolet region to the infrared region, and the illumination device and the object And a transmission filter having at least two types of wavelength characteristics, and illuminating the object with illumination light including ultraviolet rays while switching the transmission filter to take an image, and coating a film based on a plurality of obtained image data A method for detecting a coating film, comprising detecting the thickness of the film.

Applying a paint that absorbs ultraviolet rays and having fluorescence to the surface of the object to form a coating film, and irradiating the object with illumination light containing ultraviolet rays, imaging with a visible light camera and imaging with an ultraviolet camera Multiple image data obtained in different stages A method for detecting a coating film, comprising detecting the thickness of the coating film based on the method.