Optical instrument with an anti-backlash focusing mechanism
US5818648A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 24, 1997 |
| Grant date | Oct 6, 1998 |
| Priority date | — |
| Expiry date | Mar 24, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B23/2407
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
There is disclosed an anti-backlash focusing mechanism (10) for an optical instrument in which clearances between the focus control member (22) and the focusing lens cell (16) are eliminated. The mechanism (10) comprises a focusing lens means (16a) mounted in a first cylindrical member (16) which is slidable in a bore (12) in a housing (11). A focus control member (22) is rotatably mounted on the housing (11) and coupled to the first cylindrical member (16) such that rotation of the focus control member (22) causes axial movement of the first cylindrical member (16). A second cylindrical member (17) is provided adjacent the first, the second cylindrical member (17) also being coupled to the focus control member (22) for axial movement upon rotation of the latter. Biasing means (25,26) is provided to urge the first and second cylindrical members (16,17) together to eliminate clearances between them and the focus control member (22) and between the first and second cylindrical member (16,17) and the housing (11) and to prevent relative axial movement between the focus control member and the housing (11).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.