Flash photography changeover device
US4929977A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 10, 1989 |
| Grant date | May 29, 1990 |
| Priority date | — |
| Expiry date | Jul 10, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B7/08
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
In a camera having a lens shutter and a focal-plane shutter accomplishing the operations of programed exposure and aperture control, a flash photography changeover device includes a first changeover circuit for setting a lens shutter mode for operating the lens shutter as a programed shutter or a focal-plane shutter mode for controlling the shutter speed by the focal-plane shutter and the aperture by the lens shutter; a first driving device for controlling the programed exposure value and/or the aperture value of the lens shutter; a second driving device for controlling the shutter speed of the focal-plane shutter; a sequence control circuit for controlling the operating timings of the two driving devices; a setting circuit for selecting and setting automatic exposures with a natural light and a flash light; and a coercive changeover circuit for setting the lens shutter mode irrespective of the setting of the first changeover circuit when the setting circuit is set to the automatic exposure with the flash light. The setting circuit and the coercive changeover circuit may be replaced by a determining circuit for detecting and determining a limit shutter speed at which the focal-plan…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.