Automatic focusing apparatus and focus adjusting method in automatic focusing apparatus

摘要

PURPOSE:To shorten the time required for focus adjustment. CONSTITUTION:The automatic focusing device is equipped with an image pickup means 11 which picks up an image of an object set on a support body through an optical system, a driving means 12 which moves one of the support body and optical system, a setting means 13 which optionally sets a focus position retrieval range for fine focus adjustment and a minimum focus adjustment unit, a rough focus adjusting means 14 which extracts only the part of the video signal from the image pickup means 11 corresponding to a movement pitch for rough focus adjustment set by the setting means 13 and detects the focusing position of the subject within the focusing position retrieval range for rough focus adjustment to operate the driving means 12, and a fine focus adjusting means 15 which extracts only the part of the video signal from the image pickup means 11 corresponding to the movement pitch for fine focus adjustment set by the setting means 13 after the rough focus adjustment and detects the focusing position of the subject within the focusing position retrieval range for fine focus adjustment to operate the driving means 12.