Patent ID: 8866955

Claim:
A focus detection apparatus, comprising: focus detection unit which detects a defocus amount of an image capturing lens by phase-difference detection method; drive control unit which controls drive of a focus lens of the image capturing lens; evaluation value obtaining unit which obtains a contrast evaluation value of a captured image; and control unit, wherein the control unit: moves the focus lens in one direction, using the drive control unit, determines whether or not the position of the focus lens has passed a peak position at which the contrast evaluation value is maximum, based on the contrast evaluation values obtained by the evaluation value obtaining unit for captured images captured at different positions of the focus lens, stops the movement of the focus lens and obtains the focus lens stopping position if it is determined that the position of the focus lens has passed the peak position, decides the peak position using the contrast evaluation value obtained by the evaluation value obtaining unit and the corresponding position of the focus lens, detects the defocus amount, using the focus detection unit, without moving the focus lens from the stopping position, and computes a correction value for the defocus amount detected by the focus detection unit, by subtracting a defocus amount corresponding to a difference between the decided peak position and the stopping position from the defocus amount detected by the focus detection unit.