Patent ID: 7546030

Claim:
An autofocus device comprising: a lens-driving unit that drives a lens; a focal-point-position-detecting unit that detects a position of a focal point of the lens; a distance-measuring sensor that measures a distance to a subject; and a control unit that performs a focusing operation to control the lens-driving unit to drive the lens, thereby meeting the position of the focal point of the lens detected by the focal-point-position-detecting unit to an in-focus position thereof, wherein the control unit sets a driving direction of the lens and a driving speed of the lens based on (a) the position of the focal point of the lens detected by the focal-point-position-detecting unit and (b) a distance measurement result measured by the distance-measuring sensor and starts the focusing operation, wherein the control unit sets the driving direction of the lens and the driving speed of the lens to a direction of in-focus region based on the measured distance result and a first driving speed, respectively, when the position of the focal point detected by the focal-point-position-detecting unit stays away from the in-focus region based on the measured distance result with the position of the focal point staying further away from a first determined distance, and thereafter starts the focusing operation.