AUTOFOCUS APPARATUS AND METHOD

In automatically focusing on a subject in the field of view of a camera device, the camera device sets a focal length successively at one or more focal positions with an angle of the focus plane tilted so as not to be orthogonal to a normal optical path through the camera device. An image is taken at each of the focal positions. A comparison of data from each image is made so as to determine best focus. This comparison includes comparing data from at least two different locations along the tilted focus plane of at least one of the images.