Projection lens and method of using same
US5483382A · kind A · utility
3Cited by
4References
19Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Sep 17, 1993 |
| Grant date | Jan 9, 1996 |
| Priority date | — |
| Expiry date | Sep 17, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G2340/0485
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A new and improved projector lens arrangement which can automatically adjusted for focusing purposes in an easily and convenient manner according to a novel focusing method of the present invention. The projection lens arrangement generally includes three groups of optical elements aligned along a common optical axis with a variable vertex length and wide field coverage angle. One element group near the object is a doublet having a negative element with a concave surface and a positive element being bi-convex having one surface near the image complementarily shaped to the concave surface of the negative element.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.