Film and photographic apparatus
US4223990A · kind A · utility
7Cited by
3References
7Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Mar 14, 1979 |
| Grant date | Sep 23, 1980 |
| Priority date | — |
| Expiry date | Mar 14, 1999 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B2217/261
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A film magazine contains a roll of film having an image portion and a leader. The filmstrip is perforated at predetermined intervals with larger perforations in the image portion than in the leader. A camera mechanism is disclosed which uses the perforations to advance the filmstrip, detects the size of the perforations, and meters only when a large, image portion perforation is advanced to a predetermined position in the camera.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.