| 摘要 |
PROBLEM TO BE SOLVED: To eliminate the need of measuring a distance from a work beforehand, to provide images sufficient for measurement without using an expensive automatic focusing device, and to perform highly accurate measurement by fetching plural images while continuously changing the distance between a camera and the work, selecting the image of maximum contrast in them, and performing an image processing. SOLUTION: A Z stage to which a CCD camera is fixed is moved to an initial position, photographing is started from the position and movement is started in an upper direction. Image picked-up video data are successively stored inside an image memory. When the prescribed number of sheets are stored, the image data of the maximum contrast in them are searched. Then a work surface is measured by using only the searched image of the maximum contrast. |
