Wide angle photographic lens
US4311367A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 15, 1979 |
| Grant date | Jan 19, 1982 |
| Priority date | — |
| Expiry date | Nov 15, 1999 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B13/04
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A wide angle photographic lens comprises a divergent forward group and a convergent rearward group. The forward group has at least one negative meniscus lens component having its convex surface facing the object side. The rearward group has a diaphragm, at least one positive lens component disposed forwardly of the diaphragm, a biconcave negative lens component disposed rearwardly of the diaphragm, a positive meniscus lens component having its convex surface facing the image side, and a focusing lens member provided most adjacent to the image side. The focusing lens member has at least one lens movable in the direction of the optic axis. The focusing is effected by movement of the movable lens alone.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.