Patent attributes
An object of this invention is to provide an autofocus method and apparatus capable of always performing proper focusing operation. To achieve this object, a control device drives a focus lens in accordance with the operation of an operation device, and stores the stop position of the focus lens. While the focus lens is driven within a predetermined range using the stop position as a reference, the control device stores an output from an extraction device in association with the position of the focus lens. The control device determines the focusing state of the focus lens from the output from the extraction device, and when determining from the determination result that the focus lens is incapable of focusing, drives the focus lens to the stop position.