| 摘要 |
PROBLEM TO BE SOLVED: To provide an auto-focusing device for taking a high-definition moving picture and a high-definition still picture without missing a photo opportunity. SOLUTION: An auto-focusing device is provided with: a focal detection circuit 4 which extracts a medium to high frequency component from an image signal and detects a focal signal VF; a direction judging circuit in focus 502 which judges the direction in focus from the time variation component of the focal signal VF; a judgment circuit in close to focus 505 which decides whether to be in close to focus or not based on a direction memory in focus 504 storing the direction in focus, the level of the focal signal VF, and the distribution state of the direction in focus; a calculation circuit of lens controlled variable 503 which determines the moving direction and the moving distance of the lens on the basis of the focal signal VF and a result of the judgment whether it is close to focus; and a lens driving means 6 which drives lens 1a for focusing according to the output of the calculation circuit of lens controlled variable 503. Then, the auto-focusing device having high quality, satisfactory responsibility, and high precision is obtainable by reducing the moving distance of the lens or setting to zero when being close to focus. COPYRIGHT: (C)2004,JPO |
