Fixed focal length optical lens system
US8363338B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Oct 28, 2010 |
| Grant date | Jan 29, 2013 |
| Priority date | — |
| Expiry date | Mar 24, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B13/18
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A fixed focal length optical lens system includes a lens group and a diaphragm. The diaphragm is located in front of the lens group. The lens group includes three lenses, respectively the first, the second and the third lens, which are sequentially arranged as a “negative-positive-positive” separated focal power system. The first lens is a plano-concave negative lens, the second lens is a positive meniscus lens, and the third lens is a double convex positive lens. All of the curved surfaces of the second lens are bent in the direction towards the diaphragm, wherein, the focal length of the entire optical system is f, the focal lengths of the first, the second and the third lens are respectively f1, f2, and f3, and which satisfies the following requirement: −0.6<f1/f<−0.4; 1.0<f2/f<1.2; 0.6<f3/f<0.8.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.