Patent ID: 8405759

Claim:
An auto-focus device, comprising: an imaging section for receiving subject light flux made incident by a photographing lens on an image forming surface, and subjecting the subject image on the imaging surface to photoelectric conversion to output subject image data; a display section for carrying out a live view display operation using image data acquired by the imaging section; a first contrast AF section for obtaining contrast information of a subject image from the image data acquired by the imaging section, while driving the photographing lens by a first drive amount, reverse driving the photographing lens a second drive amount of half the first drive amount if a peak of the contrast information is passed, and guiding the photographing lens into a first predetermined in-focus permissible range, wherein the first contrast AF section reverse drives the photographing lens at the same speed as before the reverse drive; and a control section for, responsive to a commencement of the live view operation, performing control so that a focus adjustment operation is executed using the first contrast AF section.