Method for detecting surface defect, surface defect detecting device, method of manufacturing steel material, quality control method of steel, manufacturing equipment of steel, method for producing surface defect determination model, and surface defect determination model

摘要

The surface defect detection method according to the present invention is a method of detecting a surface defect for optically detecting a surface defect of steel, and using two or more discriminatable light sources to irradiate illumination light from different directions to the same inspection object position and drawing from two or more images by reflected light of each illumination light A detection step for detecting a surface defect at the test subject site based on the degree of overlap of the emitted bright portion.