Automatic focus control device
US4816856A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 30, 1987 |
| Grant date | Mar 28, 1989 |
| Priority date | — |
| Expiry date | Mar 30, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B7/34
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
In an automatic focus control device of a camera there are provided defocus amount calculation means for calculating a defocus amount for a predetermined focus plane of a photographic lens in the camera on the basis of the electric signal generated by a light receiving means, comparing means for comparing the obtained value on the basis of the calculated defocus amount with a reference value, control means controlling driving speed of the photographic lens by the lens driving means in response to the comparison result of a comparing means, photographic condition setting means for setting the photographic condition and reference value setting means for setting said reference value in response to the set photographic condition.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.