Autofocus system, an imaging apparatus equipped with the automatic focusing device and a portable electronic apparatus including the image pickup apparatus

摘要

PROBLEM TO BE SOLVED: To provide an automatic focusing device, an imaging device and a portable electronic apparatus capable of increasing the speed of automatic focusing processing.SOLUTION: The automatic focusing device, the imaging device and the portable electronic apparatus according to the invention comprise: a lens movable in a area corresponding to a focus area C; an image pickup element that receives light; an actuator that moves the lens; drive means that drives the actuator; and control means that controls the drive means to move the lens, obtains imaging data, calculates a target position to which the lens is finally positioned based on the imaging data and controls the drive means to position the lens to the target position. The control means is configured to obtain the imaging data in a field set while the lens is moved in a certain direction in an area corresponding to the focus area C.