Camera having an automatic focus adjusting apparatus
US4972221A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 30, 1988 |
| Grant date | Nov 20, 1990 |
| Priority date | — |
| Expiry date | Dec 30, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B7/282
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A camera including an imaging optical system and a focus detecting circuit for repeatedly performing a focus detection operation and outputting a focus signal representing the focusing state of the optical system at the time of each focus detection operation. A calculation circuit predicts, on the basis of previous and latest focus signals, the focusing state of the optical system a predetermined period of time after the detection of the latest focus signal. The predetermined period of time includes a shutter release time-lag. A driving circuit drives the optical system by an amount corresponding to the focusing state calculated by the calculation circuit. A releasing circuit begins a film exposure in response to the operation of a shutter release member. A release timing control circuit controls the releasing circuit so that it does not operate until a point of time which is earlier, by an amount equal to the release time-lag, than the predicted time.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.