Patent ID: 7505075

Claim:
A camera comprising: an image-capturing element that captures a subject image through a photographic lens; a first filter device that removes a frequency component equal to or lower than a first frequency from image-capturing signals obtained at pixels corresponding to a focus area of the image-capturing element; a second filter device that removes from the image-capturing signals a frequency component equal to or lower than a second frequency which is higher than the first frequency; a lens drive signal generation device that generates a lens drive signal used to move a focus lens; an evaluation value calculation device that calculates integrating values of first image-capturing signals from which the frequency component has been removed at the first filter device and integrating values of second image-capturing signals from which the frequency component has been removed at the second filter device, each in correspondence to a predefined position of the focus lens; a lens position calculation device that calculates a focus match lens position based upon one of a set of the integrating values of the first image-capturing signals and a set of the integrating values of the second image-capturing signals calculated by the evaluation value calculation device; and a determination device that makes a true/false decision with regard to a focus match position, calculated by the lens position calculation device, based upon a change manifested by the integrating values of the first image-capturing signals and a change manifested by the integrating values of the second image-capturing signals between predefined positions taken by the focus lens, wherein: the determination device determines that the focus match position, calculated by the lens position calculation device is a true focus match position when a ratio between; (a) the change manifested by the integrating values of the first image-capturing signals between a first lens position corresponding to a largest value among the integrating values of the first image-capturing signals and a second lens position next to the first lens position and (b) the change manifested by the integrating values of the second image-capturing signals between the first lens position and the second lens position is equal to or greater than a preset determination threshold value.