Patent ID: 8279324

Claim:
A focus control apparatus comprising: a detection unit configured to detect an object image to be focused from a sensed image; a setting unit configured to set an AF evaluation value detection area in the sensed image; and a focus detection unit configured to acquire an AF evaluation value for adjusting a focus state of a photographing optical system based on a signal output from the AF evaluation value detection area, wherein the setting unit sets a first AF evaluation value detection area tracking the object image detected by the detection unit and a second AF evaluation value detection area not tracking the object image detected by the detection unit, and wherein the second AF evaluation value detection area overlaps with the first AF evaluation value detection area, and the focus detection unit carries out computation using signal outputs in the first AF evaluation value detection area and the second AF evaluation value detection area to acquire the AF evaluation value for adjusting the focus state of the photographing optical system; and wherein, in a case in which a first state in which no object image to be focused is detected by the detection unit changes to a second state in which an object image to be focused is detected by the detection unit, the setting unit enlarges the size of the second AF evaluation value detection area to contain the first AF evaluation value detection area if the size of the second AF evaluation value detection area in the first state is small to contain the detected object image.