| 摘要 |
PURPOSE:To reduce the difference in lens focusing response speed between a long- and a short-focus side by obtaining focal length information, iris information, etc., on an image pickup device from a sensor output, and controlling the extent of lens driving in focusing according to the pieces of information. CONSTITUTION:When the correlation in a correlator 9 is completed, a signal dx indicating the extent of focusing on a subject is sent from the correlator 9 and stored in a memory 13-1. At this time, a focus lens system for a lens 1 is driven according to the extent of focusing. Then, the correlation output dx after the focus lens system is driven by some extent is stored in the memory 13-1 as well as before. At this time, the last stored contents of the memory 13-1 are transferred to a memory 13-2 through a gate 13-10. The absolute value of the difference between the contents of those two memories 13-1 and 13-2 is calculated by a subtracter 13-3, and when the value is smaller than the set value ''E'' of a comparator 13-6, a counter 13-7 counts up by one in response to a clock pulse from an oscillator 13-11. |
