Differential viewfinder masks
US5689743A · kind A · utility
4Cited by
17References
6Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 6, 1996 |
| Grant date | Nov 18, 1997 |
| Priority date | — |
| Expiry date | Jun 6, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B13/12
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A camera comprising a viewfinder for defining a field of view provided with a given aspect ratio, and a pair of front and rear masks insertable in the field of view to position respective larger and smaller openings of the front and rear masks in the field of view to change the aspect ratio of the field of view, is characterized in that a differential gear mechanism connects the front and rear masks for moving the front mask a greater extent than the rear mask is moved, to position the larger and smaller openings in the field of view.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.