AUTOMATIC FOCUSING DEVICE OF CAMERA

摘要

PURPOSE:To prevent the camera from greatly being out of focus on a subject which causes false focusing by providing a decision means which varies in specific criterion with a subject distance. CONSTITUTION:The automatic focusing device of the camera which detects the correlation of two subject images formed on a photographic element 2 through two difference optical system L1, L2 and detects an in-focus position from the detected correlation value and specific criterion varies the criterion with the subject distance. This criterion is varied to obtain a slow setting for usual distances and the point where the largest correlation is obtained between the two images at the usual distances is preferentially employed. Further, the criterion is varied so as to obtain a sharp setting for a short-distance side and the probability of misfocusing on the short-distance side is reduced even for the subject which causes false focusing like a synchronous pattern.