外觀缺陷視覺檢測的原理是基于光學特性照射到產品表面反射的差異來判斷的。例如，當光均勻垂直射入產品表面時，如果產品表面沒有任何瑕疵缺陷，反射回來的方向就不會發生改變，機器視覺所呈現到的光也是均勻的；當產品表面含有瑕疵缺陷時，出射的光線就會發生變化，所探測到的圖像也要隨之改變。由于缺陷的存在，在其周圍就發生了應力集中及變形，在圖像中也容易觀察。

　　The principle of visual inspection of appearance defects is based on the difference of reflection of optical properties on the surface of products. For example, if there are no defects and defects on the product surface, the reflected direction will not change, and the light presented by machine vision will be uniform; when the product surface contains defects and defects, the emitted light will change, and the detected image will also change. Because of the existence of the defect, stress concentration and deformation occurred around it, and it is easy to observe in the image.

　　外觀缺陷視覺檢測系統中，圖像處理和分析算法是重要的內容，通常的流程包括圖像的預處理、目標區域的分割、特征提取和選擇及缺陷的識別分類。每個處理流程都出現了大量的算法，這些算法各有優缺點和其適應范圍。如何提高算法的準確性、執行效率、實時性和魯棒性，一直是研究者們努力的方向。

　　Image processing and analysis algorithm is an important content in the visual inspection system of appearance defects. The usual process includes image preprocessing, target region segmentation, feature extraction and selection, and defect recognition and classification. There are a large number of algorithms in each process, each of which has its own advantages and disadvantages and its scope of application. How to improve the accuracy, efficiency, real-time and robustness of the algorithm has been the direction of researchers.

　　外觀缺陷視覺檢測設備特點：

　　Features of visual inspection equipment for appearance defects:

　　1.高速相機和處理技術能夠對瑕疵進行快速偵測、分類、顯示、剔除等;

　　1. High speed camera and processing technology can quickly detect, classify, display and eliminate defects;

　　2.優良的光學配備用于緊缺的瑕疵檢測，甚至是低對比度的瑕疵;

　　2. Excellent optical equipment is used for defect detection, even low contrast defects;

　　3.智能分類軟件：瑕疵根據來源被精確的分類到各個目錄中;

　　3. Intelligent classification software: defects are accurately classified into various categories according to their sources;

　　4.信息準確，實時，可靠

　　4. The information is accurate, real-time and reliable

　　5.操作簡單方便，無須深入學習即可瑕疵檢測系統;

　　5. The operation is simple and convenient, and the defect detection system can be realized without in-depth study;

　　6.加快生產速度，實現局部全檢;

　　6. Speed up the production speed and realize partial full inspection;

　　不同產品的表面缺陷有著不同的定義和類型，一般而言表面缺陷是產品表面局部物理或化學性質不均勻的區域，如金屬表面的劃痕、斑點、孔洞，紙張表面的色差、壓痕，玻璃等非金屬表面的夾雜、破損、污點，等等。

　　There are different definitions and types of surface defects for different products. Generally speaking, surface defects are areas with uneven physical or chemical properties on the surface of products, such as scratches, spots, holes on metal surface, color difference and indentation on paper surface, inclusion, damage and stain on glass and other non-metallic surfaces.

　　外觀視覺檢測系統的工作原理是：當產品表面含有瑕疵缺陷時，若遇到光透射型缺陷(如裂紋、氣泡等)，光線在該缺陷位置會發生折射，光的強度比周圍的要大，因而相機靶面上探測到的光也相應增強；若遇到光吸收型(如砂粒等)雜質，則該缺陷位置的光會變弱，相機靶面上探測到的光比周圍的光要弱。

　　The working principle of the visual inspection system for appearance is: when there are defects on the surface of the product, if the light transmission type defects (such as cracks, bubbles, etc.) are encountered, the light at the defect position will be refracted, and the light intensity will be greater than that around, so the light detected on the camera target surface will be correspondingly enhanced; if the light absorption type (such as sand and other) impurities are encountered, the light at the defect position will become weak and the phase will be weak The light detected on the target surface is weaker than the surrounding light.

　　機器視覺是一種無接觸、無損傷的自動檢測技術，是實現設備自動化、智能化和精密控制的有效手段，具有安全可靠、光譜響應范圍寬、可在惡劣環境下長時間工作和生產效率高等突出優點。

　　Machine vision is a non-contact, non-destructive automatic detection technology. It is an effective means to realize the automation, intelligence and precision control of equipment. It has the outstanding advantages of safety and reliability, wide spectral response range, long-time work in harsh environment and high production efficiency.

　　外觀缺陷不僅影響產品的美觀和舒適度，還會對其使用性能帶來不良的影響，由此可見外觀缺陷視覺檢測設備對于企業的重要性。

　　Appearance defects not only affect the beauty and comfort of products, but also have adverse effects on their performance. Therefore, it can be seen that the visual inspection equipment for appearance defects is of great importance to enterprises.

本文轉載自山東紅寶自動化官網，源文地址：http://www.hongbaozdh.com/news/74.html