Film scanner with compensation for film shrinkage
US4054912A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 9, 1976 |
| Grant date | Oct 18, 1977 |
| Priority date | — |
| Expiry date | Apr 9, 1996 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N3/38
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The invention is concerned with a means of compensating for film shrinkage in a continuous film motion telecine apparatus. A measure of the film shrinkage is obtained by deriving a signal representing the angular speed of a roller in non-slipping contact with the film, the film being driven at a constant frame rate by, for example, a smooth capstan servo-controlled to maintain the constant frame rate. The roller whose angular speed is measured may be the drive capstan itself or a separate roller. The signal so derived is dependent on the film shrinkage and thus is used to automatically control a registration adjusting means to compensate for such shrinkage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.