Camera apparatus and method for film double exposure prevention
US5321455A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 9, 1992 |
| Grant date | Jun 14, 1994 |
| Priority date | — |
| Expiry date | Dec 9, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B2217/263
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Camera apparatus operative with a film cartridge having a rotatable radial bar coded data disc thereon positioned at predetermined angular settings corresponding that indicate the condition of film in the cartridge, i.e. exposed, unexposed, partially exposed, etc.. The setting of the disc is determined during initial film spool rotation during the film loading process by counting with the optical sensor in the camera the number of bar code elements occurring between the initial set position of the disc and a reference position on the disc such as an edge of a quiet zone element normally included on the radial bar coded disc. The visual exposure indicator (VEI) positions on the cartridge are spaced about the perimeter of the cartridge such that there exist unambiguous element count ranges corresponding to each of the cartridge VEI positions. Element counting for this purpose can be performed in a cameras that operate to cause initial spool rotation during a film loading operation in either an unwind or rewind direction.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.