OPTICAL SYSTEM CONTROL DEVICE AND METHOD, AND RECORDING MEDIUM

摘要

PROBLEM TO BE SOLVED: To quickly and highly accurately perform automatic focusing control in acquiring a still image. SOLUTION: An AF control part of a digital camera is provided with a histogram generation circuit 251 for generating histogram having the width of an edge in an AF area, a noise removing part 263 for removing a noise component from the histogram, a histogram evaluation part 264 for finding out an evaluation value indicating the degree of focusing from the histogram, and a contrast calculation circuit 252 for calculating the contrast of the AF area. The AF control part is provided also with a driving quantity determination part 265 for determining the driving quantity of a focus lens and a driving direction determination part 266 for determining the driving direction of the focus lens. The driving direction determination part 266 determines the driving direction of the focus lens by using the contrast and the driving quantity determination part 265 quickly and highly accurately sets the focus lens to a focusing position while changing the driving quantity by using the histogram evaluation value and the contrast. COPYRIGHT: (C)2004,JPO