Abstract: A surface defect inspection method includes: acquiring an original image by capturing an image of a subject of an inspection; generating texture feature images by applying a filtering process using spatial filters to the original image; generating a feature vector at each position of the original image, by extracting a value at a corresponding position from each of the texture feature images, for each of the positions of the original image; generating an abnormality level image representing an abnormality level for each position of the original image, by calculating, for each of the feature vectors, an abnormality level in a multi-dimensional distribution formed by the feature vectors; and detecting a part having the abnormality level that is higher than a predetermined level in the abnormality level image as a defect portion or a defect candidate portion.

Abstract: A surface defect inspection method includes: acquiring an original image by capturing an image of a subject of an inspection; generating texture feature images by applying a filtering process using spatial filters to the original image; generating a feature vector at each position of the original image, by extracting a value at a corresponding position from each of the texture feature images, for each of the positions of the original image; generating an abnormality level image representing an abnormality level for each position of the original image, by calculating, for each of the feature vectors, an abnormality level in a multi-dimensional distribution formed by the feature vectors; and detecting a part having the abnormality level that is higher than a predetermined level in the abnormality level image as a defect portion or a defect candidate portion.

Abstract: A surface shape measuring method includes: acquiring displacement data on an object surface facing an optical displacement meter by scanning the object surface with the optical displacement meter that applies a light beam on the object surface and performs measurement; detecting an approximate range on the object surface including a groove formed on the object surface by searching the displacement data; calculating a groove start point and a groove terminating point of the groove included in the approximate range; calculating a smallest value of the displacement data in a restricted range from a center position between the groove start point and the groove terminating point to a width defined at a predetermined ratio with respect to the groove width; and calculating a difference between the smallest value of the calculated displacement data and the height of the object surface as the depth of the groove formed on the object surface.

Abstract: A surface shape measuring method includes: acquiring displacement data on an object surface facing an optical displacement meter by scanning the object surface with the optical displacement meter that applies a light beam on the object surface and performs measurement; detecting an approximate range on the object surface including a groove formed on the object surface by searching the displacement data; calculating a groove start point and a groove terminating point of the groove included in the approximate range; calculating a smallest value of the displacement data in a restricted range from a center position between the groove start point and the groove terminating point to a width defined at a predetermined ratio with respect to the groove width; and calculating a difference between the smallest value of the calculated displacement data and the height of the object surface as the depth of the groove formed on the object surface.