| 摘要 |
PROBLEM TO BE SOLVED: To solve the problem that a focusing speed is reduced since "an operating interval for situation judgement" for moving a focus lens and checking the increase/decrease of high frequency components is independently required besides the focus adjustment being an original purpose in a conventional automatic focusing device. SOLUTION: The opening and closing control (brightness control) of a diaphragm mechanism 12 is conducted by a brightness control block 15. A signal processing block 14 computes the amount of changes in first high frequency components included in the image pickup signals during the opened stat of the diaphragm mechanism 12 and in second high frequency components included in the image pickup signals during the closed state of the diaphragm mechanism 12. Depending on the size of the changes, a situation decision block 161 determines the contrast judgement of an object to be photographed and the degree of focusing judgement at that time. Bases on the determination result, a focus lens control block 162 sets the moving speed of a focus lens 11 to a large value to cover the increasing and decreasing amount of the high frequency components when it is in a low contrast state and a large out-of-focus sate. COPYRIGHT: (C)2006,JPO&NCIPI |
