| 摘要 |
PROBLEM TO BE SOLVED: To provide an automatic focusing device which conducts quick focusing. SOLUTION: The automatic focusing device detects a first integration level FV from a high frequency component of a video signal obtained from a CCD and controls drive of a lens 1 to a focus position based on the maximum and minimum values of the first integration level FV detected between prescribed fields. The automatic focusing device is provided with an image restoring circuit 22 in which video signals are predicted and restored to video signals close to a focused condition and level detecting means 22, 23 and 25 which detect second integration level FVx of the high frequency components of the restored signal and a divider 23 which calculates the ratio of the first integration levels FV and the second integration level FVx to obtain a focus evaluation signal. When the focus evaluation signal exceeds a prescribed value, the drive of lens 1 is controlled to a focus position based on the maximum and minimum values of the first integration level FV detected between shorter fields than the prescribed fields. COPYRIGHT: (C)2004,JPO&NCIPI |
