Method of and apparatus for determining the orientation of film
US5248887A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 1, 1992 |
| Grant date | Sep 28, 1993 |
| Priority date | — |
| Expiry date | May 1, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03D15/00
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A length of exposed film has a timing track which extends along one of the longitudinal margins thereof. The timing track includes a begin segment having a first width, an end segment having a different second width and a grating between the segments. The grating consists of alternating light and dark segments having a uniform width different from the widths of the begin and end segments. The two longitudinal margins of the film are scanned by respective sensors as the film advances towards a film processing apparatus. Whenever a segment passes by a sensor, the width of the segment and its position in the timing track are recorded. Since the widths of the begin and end segments differ from the width of the grating segments, the position of the begin or end segment relative to the grating can be established. This information, combined with a knowledge of which sensor detected the timing track, makes it possible to determine the orientation of the film.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.