Zoom lens and display apparatus having the same
US6285509A · kind A · utility
26Cited by
51References
47Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Sep 28, 1999 |
| Grant date | Sep 4, 2001 |
| Priority date | — |
| Expiry date | Sep 28, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B15/145527
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A zoom lens for projecting an original image onto a screen in an enlarged scale includes, in order from the screen side, a first lens unit of negative refractive power, a second lens unit of positive refractive power, a third lens unit of negative refractive power, a fourth lens unit of positive refractive power and a fifth lens unit of positive refractive power, wherein, during zooming from a wide-angle end to a telephoto end, the second lens unit and the fourth lens unit move toward the screen side.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.