Handheld viewer for transparency film
US4491434A · kind A · utility
14Cited by
11References
3Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 24, 1983 |
| Grant date | Jan 1, 1985 |
| Priority date | — |
| Expiry date | Oct 24, 2003 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B27/024
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A compact, handheld viewer adapted for use with photographic transparencies which are located within a film cassette in roll form, in a strip containing a plurality of individual scenes, or individually mounted transparencies. The viewer includes a manually operable drive system for selectively driving either a film take-up reel, for withdrawing film from a film cassette and advancing it through a projection station, or a film spool for rewinding the film into the film cassette.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.