Camera of changeable focal length
US4990945A · kind A · utility
55Cited by
1References
13Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 10, 1989 |
| Grant date | Feb 5, 1991 |
| Priority date | — |
| Expiry date | Aug 10, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B7/10
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A camera has a lens system changeable as to focal length, which is driven by a driving device so as to change the focal length thereof. The driving mechanism includes a first shifting mechanism for shifting one lens of the lens system stepwise to predetermined positions in a direction parallel to the optical axis of the lens system and a second shifting mechanism for shifting another lens of the lens system stepwise with respect to the one lens in that same direction, thereby changing the focal length of the lens system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.