Camera viewfinding system
US4047222A · kind A · utility
8Cited by
1References
12Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jan 13, 1976 |
| Grant date | Sep 6, 1977 |
| Priority date | — |
| Expiry date | Jan 13, 1996 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B19/12
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A viewfinder system for a through-the-lens viewing camera which includes a focusing screen, a field lens, a prism, and an eyepiece is disclosed where the field lens is positionable in accordance with the position of the exit pupil of the objective lens and the eyepiece is positioned in accordance with the position of the field lens. Negative optical power is introduced between the field lens and the prism, and the prism design substantially reduces the size of the prism without sacrificing viewfinder brightness.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.