Automatic focus adjusting device with driving direction control
US6222588A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 4, 1997 |
| Grant date | Apr 24, 2001 |
| Priority date | — |
| Expiry date | Mar 4, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N23/673
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An automatic focusing device includes an extracting circuit which extracts a focus signal corresponding to a degree of focus from a picked-up image signal, a focusing lens and a direction deciding circuit which decides the direction of driving the focusing lens on the basis of the output of the extraction circuit when the state of focus deviates from an in-focus state. The extracting circuit is arranged to simultaneously extract a plurality of focus signals having different frequency components from each other. The direction deciding circuit is arranged to perform computing operations on the focus signals separately from each other with respect to the focusing lens driving direction and to decide the focusing lens driving direction when the results of the computing operations come to coincide with each other.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.