Optical projection system equipped with a plate positioner
US4239381A · kind A · utility
5Cited by
6References
5Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 19, 1979 |
| Grant date | Dec 16, 1980 |
| Priority date | — |
| Expiry date | Jun 19, 1999 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70716
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
In order to position a sensitized plate in the image plane of a projection lens, the optical projection system is provided with a set of extensible jacks placed in a circle around the lens, the desired image plane being defined by the ends of the jacks when they are in the outwardly displaced position. The plate can then be placed against the ends of the jacks by means of a spherical-bearing unit which is locked in position, whereupon the jacks are caused to withdraw and the plate can be displaced in the image plane while remaining at the focusing distance. The invention is well suited to the construction of photorepeaters.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.