| 摘要 |
PURPOSE:To reduce the quantity of correlative operations to detect a focus quickly without degrading the focus detection precision by obtaining a maximum correlative position of the second photoelectric converter array to the output of the first photoelectric converter array on a basis of the output of a preparatory correlating means. CONSTITUTION:The first and second photoelectric converter arrays receive the optical image from the exit pupil of an objective lens divided into two by an optical system. The preparatory correlating means operates a preparatory maximum correlative position of the second photoelectric converter array to the output of the first photoelectric converter array. A main correlating means operates a maximum correlative position of the second photoelectric converter array to the output of the first photoelectric converter array on a basis of the output of the preparatory correlating means. A signal corresponding to the in-focus state of the objective lens is outputted on a basis of the output of the main correlating means. Thus, correlation calculation is not performed for all of a reference part but main correlation calculation is performed only near image interval data obtained by preparatory correlation to obtain an extent of image interval deviation with a higher precision. |
