| 摘要 |
PURPOSE:To obtain cross correlation with a high SN ratio by providing a means which finds the two-dimensional cross correlation coefficient between a reference image and an image to be correlated and converts it into an image signal and a means which processes an image signal digitally and identifies and measures a necessary target. CONSTITUTION:Images of a reference body 8 and a body 9 to be correlated are picked up by image pickup devices 7a and 7b and processed by an image processor 6 to display the reference image (r) on a liquid crystal display element 3a and the image (s) to be correlated on a liquid crystal display element 3b. Both images are read out with laser light and processed by the Fourier transformation of a Fourier transforming lens 4 and the Fourier-transformed image is picked up by an image pickup device 5. Then, the reference image (r) and image (s) to be correlated are pi out of phase with each other, so the difference is calculated to obtain a Fourier-transformed image as the output of the image pickup device 5, the image is passed through the image processor 6, and a digital processor 13 performs threshold value processing, etc., to decide and measures the necessary target automatically. Consequently, the cross correlation is obtained with high SN ratio. |
