Mirror system for a single lens reflex camera
US4786928A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 4, 1987 |
| Grant date | Nov 22, 1988 |
| Priority date | — |
| Expiry date | Dec 4, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B19/12
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
In a single lens reflex camera, a mirror can be positioned at an angle between the rear of the taking lens and the film to reflect the light rays that come through the lens, on to a focusing screen of the viewfinder, and it can be positioned out of the way to expose the film. The mirror is supported to swing forward toward the rear of the lens and downward to at least partially below the film, simultaneously, from its light-reflecting position to a non-reflecting inverted position substantially facing the bottom of the camera. This advantageously permits the back focus of the lens required to clear the mirror for movement from its light-reflecting position to out of the way to expose the film, to be reduced.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.