Detection imaging method and apparatus of strip surface flaw

Abstract

The invention discloses an imaging method and a device for detecting band surface defects, wherein the method comprises establishing a sync signal generating unit to generate sync signals, synchronously controlling a switching unit and a camera shooting unit, establishing a light source switching unit, using the switching unit to switch and control the following two light sources, and using the two light sources to alternatively light the surfaces of bands, and respectively and only forming a single ground (a light field, a dark field) to image with the camera shooting unit in a scanning cycle, and obtaining total band surface defect images. The same defect on the band surface can be accurately matched with images which are formed on the same camera shooting unit and different illumination fields. The method avoids the post-treatment problem which is generated by the same defect which repeatedly images, greatly improves the accuracy of detecting the band surface defects, and in addition, and the method further lowers the production cost of the image device and the complexity of the structure.

Description

technical field [0001] The present invention relates to the detection of surface defects on the finished strip, more specifically, to a method and device for detecting and imaging defects on the surface of the strip. All the defects and the images of the same defect on the strip surface under different field illumination can be accurately matched. Background technique [0002] The strip surface defect detection system based on machine vision has been widely used in the world's major strip production enterprises. This type of detection system first uses a CCD camera to obtain the surface image of the strip, and then analyzes the image data to draw a detection conclusion. Therefore, the clarity of the imaging and the difference between the raised defect and the background directly affect the detection effect of the visual inspection system. [0003] There are many commonly used imaging methods at present, including bright field imaging, dark field imaging and transition fiel...

AI Technical Summary

Problems solved by technology

[0004] In view of the above-mentioned shortcomings in the prior art that single-field imaging is prone to missed detection, double-field imaging has a complex structure, high cost, and poor real-time performance, the purpose of the present invention is to provide a method and device for detecting and imaging strip surface defects. The imaging method and device have simple structure, low cost, and good real-time performance, so that the images formed by the same defect on the surface of the strip under different field illumination can be accurately matched

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