| 摘要 |
PROBLEM TO BE SOLVED: To reduce the parts number such as an image pickup element, etc., by compressing an image of the surface of a to-be-inspected material in a single direction for imaging with an optical technique, so that high inspection precision is kept. SOLUTION: When the inspection with high precision especially in a single direction of a two-dimensional image is required, the image is compressed in a single direction far imaging as follows. The surface of a slab 2, acting as a to-be-inspected material, is irradiated with slit light from a light source 1. After the reflected light is converged through a lens 3, through an image compressing means 4, such as a convex mirror, etc., optically compressing the image in only a single direction, height or width, the rectangular image with large height/width ratio on the to-be-inspected material is imaged on a square or a rectangular two-dimensional image pickup element 5 with small height/width ratio. The image obtained in this way is analyzed with an image processing device 6, for inspecting quality of the surface of to-be-inspected material. So that, while high precise inspection is performed, the numbers of the image pickup element 5 and the image processing device 6 are reduced, and reduction of the east of equipment and improvement of maintenance characteristic are possible. |
