Zoom lens
US5815320A · kind A · utility
36Cited by
3References
35Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Feb 12, 1997 |
| Grant date | Sep 29, 1998 |
| Priority date | — |
| Expiry date | Feb 12, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B15/173
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A zoom lens is disclosed comprising, from front to rear, a first lens unit having a positive refractive power, a second lens unit having a positive or negative refractive power, a third lens unit having a positive refractive power, and a fourth lens unit having a negative refractive power, wherein rules of design are set forth in order to minimize the bulk and size of the lens system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.