| 摘要 |
PURPOSE:To simpify a structure and to measure sizes in a short time, by using an optical system in an image sensor, forming the image of a body to be measured, utilizing the brightness data from light receiving elements based on said image and the magnification of the optical system, thereby preforming computation to obtain the sizes. CONSTITUTION:An image forming lens 7 is provided as an optical system between a photomask 1 and an image sensor 4. By moving the lens 7 along the axial direction, the image of a pattern 2 is formed as a brightness image by the sensor 4. Each light receiving element 5 is made to be either a bright state or a dark state by the formed pattern image. The element outputs the bright or dark signal independently. The signal is inputted in a bit number cunter 6, where the numbers of the bright or dark elements, especially the numbers arranged in the longitudinal and lateral directions are counted. The results are inputted in an operating part 8. The size of the pattern image is computed as n.DELTAS of the elements 5 and their number (n). Therefore, the size of the pattern 2 can be instantaneously measured, and the constitution is very simple. |
