| 摘要 |
An automatic focusing system for a video camera is disclosed in which an automatic focusing operation is performed by a focus evaluating value formed in response to a video signal obtained by an image sensing circuit. A first focusing motor control circuit controls the rotation of a focusing motor so that a focusing lens is once fixed in the position where the focus evaluating value takes the maximum value. A second focusing motor control circuit changes the focusing motor by a predetermined very small amount, to determine the slope of the focus evaluating value, which change is repeated until inversion of the slope, that is, the maximal point, is detected. As a result, the position of the focusing lens is corrected at the maximal point of the focus evaluating value. When the correction amount exceeds a predetermined value, the first automatic focusing operation by the first focusing motor control circuit is resumed.
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