Photographing apparatus with automatic focus

Abstract

A photographing apparatus is provided that comprises a photographing lens capable of moving a focal plane of a subject image, a CCD for receiving the subject image and outputting a signal into which the subject image is photo-electrically transferred, as image output, a motor section for driving the photographing lens, and a CPU for controlling an operation of the motor section. This CPU divides a range for enabling driving of the photographing lensinto a minimum number of or more sections which are capable of being interpolated, drives the photographing lens to each divided section in sequence, figures out a focus signal based on a photographing signal obtained from the photographing device at the each driving position, and performs interpolation processing of an evaluation value obtained from the focus signal. Further, by the interpolation processing, the CPU derives a focus position of the photographing lens which position causes the focal plane to coincide with the photographing plane. In addition, the CPU drivingly controls the motor section to drive the photographing lens to the derived focus position. The photographing apparatus with this configuration ensures interpolation accuracy, thus offering an excellent balance of focus-position accuracy in an entire driving range of the photographing lens and time needed for obtaining the focus position.