Control for optical system having multiple focal lengths
US5349476A · kind A · utility
4Cited by
10References
10Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 1, 1993 |
| Grant date | Sep 20, 1994 |
| Priority date | — |
| Expiry date | Mar 1, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B7/10
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An optical system including first and second lens groups disposed for relative movement along an optical axis and coupled together by a cam and follower mechanism for controlling such relative movement to change the focal length of the optical system. The system is characterized by a mechanism for offsetting relative movement between the lens groups along the optical axis caused by lateral movement of the lens groups essentially normal to the axis, thereby to maintain the focal length constant in the presence of the lateral movement.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.