A focus detection method includes moving a focusing lens group from the
near extremity toward the far extremity in a search operation, and
stopping the focusing lens group upon first detecting an in-focus state
to determine an in-focus position of the focusing lens group when
detecting a focus state in each of a plurality of focus detection areas
while performing the search operation, and moving the focusing lens group
firstly to one of the near extremity and the far extremity which is
closer to a current position of the focusing lens group and subsequently
toward the other thereof, and stopping the focusing lens group upon first
detecting an in-focus state to determine an in-focus position of the
focusing lens group when detecting a focus state in the single focus
detection area while performing the search operation.