Automatic focusing apparatus
US8000591B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Apr 28, 2010 |
| Grant date | Aug 16, 2011 |
| Priority date | — |
| Expiry date | Apr 28, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N23/672
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An automatic focusing apparatus includes: a focus detector photoelectrically converting at least a part of a photographing beam; a defocus computer calculating a defocus amount based on an output of the focus detector; a driver driving a focus lens based on the defocus amount; and a unit setting a maximum time period for charge accumulation in the focus detector. If the accumulated charge in the focus detector reaches a threshold within the period, when the accumulated charge in the focus detector reaches the threshold, the defocus computer calculates a defocus amount using an output of the focus detector and outputs the defocus amount to the driver. If the accumulated charge in the focus detector does not reach the threshold within the period, when the period lapses, the defocus computer calculates a defocus amount using an output of the focus detector and outputs the defocus amount to the driver.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.