Patent ID: 8120698

Claim:
A focus control apparatus for exercising focus control in an image pickup apparatus, the focus control apparatus comprising: a first contrast signal generator for extracting a first high frequency component depending upon a first cutoff frequency from a video signal and generating a first contrast signal of the video signal on the basis of the extracted first high frequency component; a second contrast signal generator for extracting a second high frequency component depending upon a second cutoff frequency which is higher than the first cutoff frequency from the video signal and generating a second contrast signal of the video signal on the basis of the extracted second high frequency component; and a controller for using a quotient obtained by dividing a value of the first contrast signal by a value of the second contrast signal as a parameter and exercising focus control on the basis of the parameter, wherein the first and second cutoff frequencies are set so as to cause a value of the parameter to assume a peak when a focus lens in the image pickup apparatus is located at positions of a predetermined distance behind an in-focus position and decrease when the focus lens is located behind the peak.