Zoom lens system
US5978149A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 7, 1997 |
| Grant date | Nov 2, 1999 |
| Priority date | — |
| Expiry date | Oct 7, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B15/142
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A zoom lens system includes two lens components, and zooming is performed by moving a first lens component. The zooming is performed along a zoom curve such that the first lens component is moved out so that in-focus condition is obtained at a subject distance predetermined with respect to each focal length. As the subject distance, an excess focal length or a subject distance where the far side of the depth of field is the maximum flash reachable distance or a subject distance where the near side of the depth of field is the shortest object distance or a subject distance where the object distance or the magnification is fixed is set according to the purpose.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.