Film sag detecting device for sound cinecamera
US4326781A · kind A · utility
0Cited by
3References
2Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Mar 23, 1978 |
| Grant date | Apr 27, 1982 |
| Priority date | — |
| Expiry date | Mar 23, 1998 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B31/02
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
This film sag detecting device for a sound cinecamera is provided with an opto-electronic coupler located along a film path which is formed between a means for intermittent feeding of a film for exposure and a means for continuous feeding of the same for recording sounds thereon. The opto-electronic coupler comprises a light emitting element and a light receiving element and it is placed to allow the film to interrupt a light path which bridges the two light elements exclusively when the film excessively sags, so as to detect any excessive sag of the film.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.