Two-group zoom lens
US4726666A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 4, 1985 |
| Grant date | Feb 23, 1988 |
| Priority date | — |
| Expiry date | Oct 4, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B15/1425
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A zoom lens is known which has a first lens group having a negative refracting power and a second lens group having a positive refracting power arranged from an object side, a spacing between both the lens groups being varied to thereby vary magnification (variable power). In order to make such zoom lens compact, the refracting power of the negative lens group is intensified and the negative refracting power is arranged in a portion at the rear of the positive lens group. The portion in the positive lens group is composed of a set of positive and negative lenses, and at least one surface of the lenses is made to be an aspherical surface to correct aberrations.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.