| 摘要 |
PROBLEM TO BE SOLVED: To provide an automatic focus system capable of quickly moving a lens to a detected focal point, for quick focusing. SOLUTION: A focal point voltage is detected from a high-frequency component of the video signal obtained from an imaging element 2. A lens 1 is driven to a specified position based on a differential voltage between specified fields of the focal point voltages, so that the differential voltage comes to be minimum. Thus, focusing of image light to the imaging element 2 is performed in hill-climbing method. An FIFO20 for storing lens position data is provided, and if the minimum value of the differential voltage is detected, a drive signal is generated based on the lens position data, read from the FIFO20, which proceeds for the time period required for the process to acquire the drive signal for driving the lens from the imaging element 2, to move the lens 1 to the position specified by the lens position data. COPYRIGHT: (C)2004,JPO&NCIPI |
