Focusing apparatus and focusing method
US7911527B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Aug 18, 2008 |
| Grant date | Mar 22, 2011 |
| Priority date | — |
| Expiry date | Sep 18, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N23/632
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A focusing apparatus according to an aspect of the present invention comprises: an image pickup device which obtains an image signal of a subject that is captured by an image capturing device, wherein the image capturing device incorporates a focus optical system therein; a search interval calculating device which acquires contrast characteristics that are obtained for a subject of a predetermined spatial frequency at a predetermined focal length and calculates a search interval in capturing of an image based on the contrast characteristics; a focus evaluation value acquiring device which moves a focus lens to a detecting point for each search interval in a predetermined searching range and acquires a focus evaluation value at each detecting point from the image signal; and a focus detecting device which detects a focus position by using the focus evaluation value at each detecting point that is acquired by the focus evaluation value acquiring device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.