Optical apparatus for changing focus and focal length
US6011657A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 5, 1998 |
| Grant date | Jan 4, 2000 |
| Priority date | — |
| Expiry date | May 5, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B7/102
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Apparatus having an optical system including two lens groups movable along an optical axis includes a zooming motor and a linkage interconnecting zooming motor and the two lens groups such that axial displacement of one of said lens groups effects axial displacement of the other of said lens groups. The linkage is configured so as to have a zooming zone, wherein axial displacement of one lens group effects substantially faster axial displacement of the other of said lens groups, such that the focal length of the optical system may be changed, and a focusing zone, wherein axial displacement of the one lens group effects substantially slower axial displacement of the other of said lens groups. Accordingly, the optical system can be focused by the zooming motor without requiring a large amount of lens travel.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.