Apparatus for automatically focusing a camera lens
US5249058A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 12, 1993 |
| Grant date | Sep 28, 1993 |
| Priority date | — |
| Expiry date | Jan 12, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N23/673
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The present invention relates to an automatic focusing camera in which an automatic focusing operation is performed by detecting a high frequency component of a video signal obtained from an image sensor device at every predetermined period, and has a theme that the automatic focusing operation can be performed within an extremely short time. To this end, by a search means, a focus lens is moved from a first position to a second position with relatively coarse steps to obtain a focus evaluating value for each step. In a first method, after the focus lens is moved to the vicinity of a lens position corresponding to a maximum focus evaluating value obtained by the search means, the focus lens is moved with small incremental steps to find a true maximum focus evaluating value. In a second method, a true maximum focus evaluating value is found from interpolated focus evaluating values obtained by interpolation of focus evaluating values exist in the vicinity of the maximum focus evaluating value obtained by the search means and adjacent to each other.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.