FOCUS CONTROL CIRCUIT

PURPOSE:To prevent the fluctuation of a focus lens caused by hand shaking by providing a detection area which is bigger than a focus area, comparing video signals separated by a prescribed time interval in the detection area, arithmetic-operating the movement vector quantity of a substance to be filmed and moving the focus area based on the result of this arithmetic operation. CONSTITUTION:The detection area including the focus area and being bigger than the focus area is provided; the data in the detection area separated by the prescribed time interval are compared by a vector arithmetic operation means 14; the movement vector quantity of the substance to be filmed in the focus area is arithmetic-operated and the focus area is moved by a focus area control means 15 according to the movement of the substance to be filmed. Due to that, the substance in the focus area is not changed by hand shaking and the spectrum components of the video signals in the focus area detected by a vector detection means 6 are made to be the same. Thus, the fluctuation of the focus lens 2 caused by the hand shaking can be prevented.