Camera having a focus controller capable of focusing in horizontal and vertical directions of an image

摘要

In a focus control apparatus of a camera, a luminance signal component having a relatively high frequency is extracted from a video signal by use of a filter so as to accumulate the extracted luminance signal component by an accumulator. A difference circuit computes a difference in the accumulated signal component between two adjacent horizontal scanning lines such that the maximum value of the difference is held by an accumulator unit for a vertical scanning period. The focus of the lens is controlled such that the accumulated value produced by the accumulator unit takes the maximum value. A high focusing accuracy is obtained not only for an image in which the luminance greatly varies in the horizontal direction of the image having a vertical stripe pattern but also for an image associated with a large change only in the vertical direction having an image of vertical stripes.