Lens system
US7564634B2 · kind B2 · utility
12Cited by
4References
9Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Nov 28, 2007 |
| Grant date | Jul 21, 2009 |
| Priority date | — |
| Expiry date | Jan 18, 2028 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B13/22
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A lens system comprises a first lens negative in power, a second lens positive in power, a third lens negative in power, a fourth lens positive in power, a fifth lens negative in power, and a sixth lens positive in power. The lens system meets a criteria of TT/f≦1.68 and 0.3<f/f23<0.4, wherein TT denotes a distance between an object-side surface of the first lens and an image plane of the lens system; f23 denoting an effective focal length of a combination of the second lens and the third lens; f denoting an effective focal length of the entire lens system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.