Focus detection apparatus capable of detecting an in-focus position in a wide field of view by utilizing an image contrast technique

摘要

A focus detection apparatus selects one of a plurality of distance measurement areas in a photographing area, and obtains an in-focus point on the basis of contrast data of an object in the selected distance measurement area, thereby driving a photographing lens. When the selected distance measurement area is set by an area setting unit, an MTF characteristic value corresponding to the selected distance measurement area stored in a ROM is read out. An MPU obtains a contrast peak value of a first detection frequency component, and detects a position of a first peak value. The MPU predicts an existing area of a contrast peak value of a second detection frequency component higher than the first detection frequency component on the basis of the detected first peak value position and the MTF characteristic value read out from the ROM. The MPU obtains the contrast peak value of the second detection frequency component in accordance with the predicted existing area of the peak value to detect a second peak value. The MPU drives the photographing lens in accordance with the positions of the first and second peak values.