Patent ID: 7209175
Filing Date: 2007-04-24
Classification: G03B,H04N

Abstract:
1. An autofocus apparatus for focusing an image of an object on a surface of an image pickup element for producing an electrical signal utilized as a picture signal, comprising: a photographing optical system including a focus adjusting lens movably provided; a first focusing estimating device to produce focusing information on the basis of a level of a predetermined frequency component included in the electrical signal of the image pickup element; a storage device to store into a memory a correction value when said first focus estimating portion creates the focusing information indicating that the image on the image pickup element is focused on the object; a second focusing estimating device including an imaging lens to image at least a part of light of the object image, split from said photographing optical system, an image re-forming system to re-form images of light beams having passed locations different on pupil position of the imaging lens, a light receiving device to receive the light beams of the images formed by the image re-forming system, a positional deviation detecting device to detect an imaging positional deviation on the light receiving device, and a correcting device to correct the imaging positional deviation detected by the positional deviation detecting device with the correction value stored in the memory, said second focusing estimating device generating second focusing information to focus the image of the object on said image pickup element with respect to the object; a selecting device to select one of said first focusing estimating device or said second focusing estimating device; and a moving device to move said focus adjusting lens on the basis of the focusing information generated by the selected focusing estimating device by said selecting device.