Automatic focus video camera

Abstract

Abstract PURPOSE:To reduce an unnecessary automatic focusing action and to obtain an easy-to-see screen by detecting the movement of a subject based on the fluctuation of a focus evaluation value in plural sampling areas, and changing a focusing area according to the movement of the subject. CONSTITUTION:For example, a black subject 13 is in a position A before a white wall 14, and a focusing is executed. A fluctuation supervising circuit 11 selects four of sampling areas Sa9-Sa12 as the focusing areas so that the subject can go to an area center, and the focusing action is executed by using the sum of focus evaluation values L9-L12. Next, when the subject 13 is moved in a right direction facing a camera 15 and goes to a position B, a circuit 11 decides, from the fluctuation of the distribution pattern of the focus evalua tion values, that the subject is moved from the areas Sa10 and S11 to areas Sa8 and Sa9, simultaneously, a selecting circuit 12 selects areas Sa7-Sa10, and the automatic focusing action is executed based on the sum of focus evalua tion values L7-L10. In such a way, the unnecessary automatic focusing action can be reduced, and the easy-to-watch screen can be obtained.

Inventors

• 👤 Masatada Kawakami

Bibliographic Details