| 摘要 |
PURPOSE:To determine the position of a tangent line highly accurately without using a statistical method, by obtaining the specified position of a curve to be measured on an image as the maximum number of optical points in the same direction as the tangent line by using an image technology. CONSTITUTION:A measuring apparatus 1 for measuring an image is composed of an optical magnifying glass, a CCD type image sensor 3, a guide device 4, a position control device 5, an image processor 7 and a CPU8. By the apparatus 1, a dent 9 on a material to be measured 6 is optically read and stored in the CPU as an image. At this time, the dent 9 and a cut surface 10 are displayed on the image as the difference between bright and dark parts. These are image noises of bright and dark parts between both parts. The noises are judged by the divided region and the binary coded values of the black and white regions, and the noises are removed. Then the boundary part between the dent 9 and the cut surface 10, i.e., a contour curve 15, is displayed by the group of discontinuous optical points 16. The distribution of the optical points 16 in the direction X and the direction Y for the tangent line to be obtained is computed. The maximum value of the total number of the distribution is obtained as an intersection 11 of the contour line 15 of the dent 9. |
