| 摘要 |
PROBLEM TO BE SOLVED: To make an automatic focussing device performable optimum automatic focusing action in both cases that focusing accuracy is regarded as important and that quick photographing performance is regarded as important. SOLUTION: The automatic focusing device is provided with a focus lens 101 which is focused on a subject image, a motor 103 and a focus lens driving circuit 104 for driving the lens 101, and an imaging device 112 converting the subject image formed by the lens 101 into an electric signal. A signal showing the high frequency component of the luminance of a subject is extracted from an output signal from the imaging device 112, the high frequency component at every step position is stored while driving the lens 101 at a specified step within a focusing feasible range, and scanning action to extract a focus peak position where the high frequency component is maximum is performed, then the number of times of scanning action is changed in accordance with the state of a switch SW2 designating photography in the case of performing control to drive the lens 101 to the focus peak position obtained by the scanning action. COPYRIGHT: (C)2004,JPO&NCIPI |
