| 摘要 |
PURPOSE:To make immune to effect caused by the scratch or the dust of a film and to obtain a focusing position in a short action time by dividing a line sensor into plural areas and determining the focusing position in virtue of previously determined selection characteristic based on the condition of variance of the lens position where a contrast signal becomes the largest in each section. CONSTITUTION:All of the line sensor 34 is divided into plural areas to obtain contrast every area. A CPU 46 respectively obtains lens positions x1-x3 where the contrast signals CS1-CS3 are the largest every section stored in a RAM. The variance of the focusing positions x1-x3 obtained thus for the respective sections I-III is obtained and the condition of the variance whether or not it is in the depth of the focus of the lens 20 detected by a sensor 48 is examined. The focusing position (x) is determined according to each condition. The probability of focusing on the scratch and the dust can be made small and the time necessary for determining the focusing position can be shortened. |
