Multiple projector planetarium drive system
US4639224A · kind A · utility
12Cited by
6References
13Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 26, 1985 |
| Grant date | Jan 27, 1987 |
| Priority date | — |
| Expiry date | Apr 26, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09B27/00
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A planetarium includes a fixed star field projector and a plurality of planet projectors spaced from the star field projector. A computerized control controls the rotation of the projectors, each of the planet projectors being controlled in its rotation about a pair of perpendicular axes alternatively in two modes, in the first mode the projected image traversing normal apparent orbital or other path in the star field and in the second mode the image traversing the shortest path from an initial point to a terminal point in the star field which points represent different times and/or points of observation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.