| 摘要 |
PROBLEM TO BE SOLVED: To provide a device for detecting a defect on a cylindrical object with high defect detection ability at a low cost. SOLUTION: This device is provided with a pattern light projection means 1 for projecting a regular pattern onto the surface of a cylindrical object 2 to be inspected, an image data generation means 5 for picking up an image of the regular pattern projected onto the surface of the cylindrical object 2 and for generating image data, a shading correction means 9 for removing a shading signal level in the image data and a means 10 for converting the shading corrected image data into binary image data and evaluating the regularity of the projection pattern in the image data converted into the binary image data. A defect is accurately detected without scanning the same area for plural times and without performing averaging or addition. |
