| 摘要 |
PURPOSE:To stabilize the automatic focusing motions and prevent overshooting in focusing by performing judgement about focusing without averaging during the period from immediately before focusing till the motor being stopped with completion of focusing. CONSTITUTION:A microcomputer 20 acquires the distance measuring condition and gives it to a calculating means 16 as a defocus quantity. After averaging the defocus quantity, judgement about focusing is made with the defocus value obtained by averaging if focusing has been established. If out of focus at present, judgement is passed that it is not immediately before focusing unless the defocus value as the average is below the predetermined value n1, followed by judgement about focusing using the mean value. When below tame value n1, i.e., when the defocus quantity is small, judgement is passed that it is immediately before focusing, followed by judging about focusing using not the mean value but the current defocus quantity acquired with one run of distance measuring. When judgement about focusing is passed, the motor 21 is stopped. |
