| 摘要 |
Light sources emit irradiation lights respectively, so that edge parts of mutual irradiation areas (inspection areas) are superposed one another. The imaging apparatus receives regular reflection lights and generates two images corresponding to each of the light sources. A main control part combines two images and determines presence/absence of a defect. By irradiating an inspected surface A with the irradiation lights from mutually different directions, a position of an area showing the defect in each image is slightly deviated. Therefore, even if a dimension of an area showing the defect is small in each image, by superposing two images one another, the dimension of the area showing a defect part becomes large in the image after composition. Thus, an accuracy of defect detection on the edge part of the inspection area can be improved.
|
