Slide projector having two image-projection systems which operate with a single slide tray
US4466716A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 24, 1981 |
| Grant date | Aug 21, 1984 |
| Priority date | — |
| Expiry date | Jul 24, 2001 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B23/18
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The slide projector includes side-by-side image-projection systems and a circular slide tray, with slides passing in operation directly between the slide tray and either of two slide gates, the slide gates moving between a first position in which slides are acquired and released, and a second position in which slides are projected onto a screen. A slide lifter, a slide tray lock, slide clamps on each slide gate, and the slide gates are operated in a particular sequence relative to the movement of the slide tray to insure proper handling of the slides in the projector. The slide tray fits on a central hub which in turn is independently driven. Sensors are provided to continuously detect the position of the lifter, the slide gates, and the slide tray. A front end assembly which incorporates lenses which move laterally and vertically, with the longitudinal axes of the lenses remaining parallel at all times, provides precise image alignment, including image overlap and separation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.