Fish eye lens system
US4647161A · kind A · utility
203Cited by
1References
15Claims
0Family size
Inventor
Key dates
| Filing date | Jun 24, 1985 |
| Grant date | Mar 3, 1987 |
| Priority date | — |
| Expiry date | Jun 24, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B13/04
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A high performance medium speed fish eye lens system is provided, capable of compensating all aberrations except the distortion at an aperture ratio of at least 1:4.2. The lens system consists of a first lens group (G1) of negative refractive power including two negative lenses curved towards the object, a middle positive lens component (G2) curved towards the object, which lens component can be composed of a cemented doublet, and a last lens group (G3) of positive refractive power consisting of a cemented doublet or a cemented doublet and an additional positive single lens both curved towards the image.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.