Projection lens system with variable air space
US4776682A · kind A · utility
4Cited by
4References
5Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Oct 15, 1986 |
| Grant date | Oct 11, 1988 |
| Priority date | — |
| Expiry date | Oct 15, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B13/16
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A projection lens system comprises a first group of lenses having at least one variable spacing for correcting aberration, and a second group of lenses having a variable spacing for focusing with the lens located closest to an image being fixed. It corrects variation of aberration and allows variable projection magnification.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.