An optical apparatus includes an optical system including first and second
movable lens units independently movable in an optical axis direction,
and a controller causing the first movable lens unit to wobble in the
optical axis direction based on contrast information. The optical system
satisfies |tk/L|<15, where tk represents a distance from an image
plane position to an exit pupil position when the exit pupil position is
closest to the image plane position, L represents an effective diagonal
length of an image at the image plane position. The controller causes the
second movable lens unit to wobble in the optical axis direction to
reduce variation of the position of the exit pupil in association with
the wobbling of the first movable lens unit. The apparatus is capable of
suppressing image twitching while obtaining a high focusing performance.