Focusing method, suitable for an image capturing apparatus using in an environment of low brightness and image capturing apparatus using the same

摘要

A focusing method, suitable for an image capturing apparatus using in an environment of low brightness, is provided herein. The focusing method includes that an image sensing unit in the image capturing apparatus is wholly or partially divided into a plurality of regions, and digital image data sensed by the image sensing unit is divided into a plurality of sets corresponding to the regions of the image sensing unit. The regional image data corresponding to each of the regions are summed up during the focusing step, so as to obtain a sum of data for each region. Each sum of data is used to calculate a corresponding contrast value, and the contrast value is used to perform calculations for the focusing step, so as to obtain a focus.